Federal Renister / Vol. 50, 216 1 Wednesday, November 1685 1 Proposed Rules 48938 No. -13, ENVIRONMENTAL PROTECTION DARI: Written comments should be FOR FURTMKl IWtORYAfIW COWIACT: AOEt!CY submltled by March 13.19tX. A publlc Joseph A. Cotruvo. Ph.D., Director, hearing will be held in Washington, D.C. Criteria and Standards Division. Office 40 CFR Parl 141 on January 28 and 29.1968, beginning at of Drinking Water (WH-5501. 9:OO 6m in Conference 1, adjacent IOW-FRL-2058-71 Room Envlronmentel Protection Agency. 401 M to the Washington Information Center, Street. SW., Washington. DC 2~80. Natlonrl Pdmsry Drlnklng Watw EPA, 401 M Street SW.. Washington, telephone (202) 382-7575. DC. Regulatlona; Synthetic.Orgrnlc Table of Contmt~ Chemlcalr, lnorganlc Chemlcrla and Aomesses: Send written comments to 1. Statutory ilequirements Mlcroorganluna Comment Clerk, Criteria and Standards 11. Regulatory Framework Division. Office of Drinking Water 111. Regulatory BackRround AQIMCV: Environmental Protection (WH-SSO), Environmental Protection Agency [ EPA). A. Interim Regulntlons Agency, 401 M Street SW.. Wnshington. B. Natlonnl Academy of Sclences (NAS) ACTIOW: Proposed rulemaking. C. Revised -- -...... ------____- DC 20480. A copy of the comments and Issues BeinR Addrersed In Regulations SlIYYAllV: Thlr proposed rule under the supporting documents will be available for review uuring normal buslnees hours 0. Summnry of Commentr Snfc Ihiriking Water Act (42 U.S.C. W IV. Regulatory Alternatlves ot srq. 1 would entatdish Recommended at the EPA. Room 2904 [rear). 401 M Street SW., Wtrshington. DC 20400. It Is V. Fnctors in the Development of RMCI, Mtiximiim Contaminant l~vels(RMC1.s) A. Selection of Contaminmts for for synthetic orgtinic chemicals (SOCs). requested that anyone planning to attend the public hearing (especially Rcgulfllion inorxtinic chemicals [IOCs) and B. Sources of Occurrence end lluman micrnl)ioIoRical parameters in drinking those who plan to make statements) Exposure Date water. I'roporcd RMC1.s (goals) for register in advance by calling or writing C. Evaluation of llealth Effects and substuncer considered to be probable Ms.Arnetta Davis at 202/382-7575. EPA. Delermindlion of RMCL. humrln t:arcinogenr are set at the zero WlC550.401 M Street SW.. Washington. 1, Non-carcinogens-AhDls level rind RMCLs for substances not DC 20480. Persons planning to make 2. Calculatlon of the RMCla treated (in probable human carcinogens statements at the hearing are 3. Short-term Assessmenls Are set hased upon chronic toxicity or encouraged to submit written copies of 4. Carcinogens sther data. SOCn. lOCs and their remarks at the time of the heoring. 5. Evidence of Carcinogenicity VI. Microbiological RMCL microorganisme that are not included in Supporting documents cited in Section XI will be available for inspection at the A. Interim Regulations and Recent this propond may be considered for Outbreaks of Waterborne Disease subsequent rulemaking under the Safe Drinking Water Supply Branches in ' 8. Told Coliform Bacteria DrinkinR Water Act. EPA's Regional Offices. c. Turbidity RMC1.s are nun-anforceohle henhh 1. JFK Federal Bldg.. Boston. MA 02203. 0. Giardia goals which are to be set at leveln which Phone: (817)Zs-8~18. Jerome Healy E. Pathogenic Viruses would rcsult in no known or anticipated 11.28 Federal Plaza. Room 824. New F. LeRionellne advcrat! health effects with an adcquate York. NY 10278. Phone: (212) 284-1800. C. tieterotrophic Bacteria margin of safety. Thin propogal is the Walter Andrews II. Treatment Technique Reguiremenls 1. Mandatory Filtration and Disinfection initial nttige in rulemaking for the 111. 8th 6 Walnut Sts.. Philadelphia. PA entahlishmenl of primary drinking water of Surface Water for Microo-anisms 1WoB. Phone: (215)597-9673. Bernie 2. Mandatory Disinfection of Ground reguliltions for Ihe SOCs. lOCs qad Sarnowski microbials. Following this proposal. Water IV. 345 Courtland Street. Atlanta. GA VII. lnorpnic RMCLs Maximum Contaminant l~vels(MCLs) 30385. Phone: (404)W1-3781, Robert A. Availability 01 Analytical Methods orid monitoring/reportinR requirements Jourdan 8. Proposed RMCLs will be proposed when the RMCh are V. 230 Dearborn Chicago. IL 80804. 1. Arsenic promdga led. MCLs are cnfurceoble S. SI.. Phone: (312) 888-8176, Joseph 2. Asbestos stonclmls and are to be set as close to tlarrison 3. Barium the RMCla as is feasible and are based 4. Cadmium Elm SI.. Dallas, TX upon treatment technologies and cost. VI. lUn 75270. 5. Chromium Puhlic comments are solicited on each Phone: (214) 787-2820. lames Graham 0. Copper of thc proposed RMCLa as well as on V11.726 Minnesota Ave.. Kansas City, 7. Lead the mgu!ntory approach being KS BB101. Phone: (913) 23&2815, 8. Mercury considered. Specific scientific and Gerald P. Foree 9. Nitrate and Nitrite technical reviews and comments are VIII. 1880 Lincoln SI.. Denver. CO 80295. 10. Selenium Phone: (303)293-2815. Marc .4lston C. lOCs for Which RMCLs are not requentccl on the support docutnents on Ropored analyticiil methods and health effects. IX. 215 Fremont SI.. Sen Francisco. CA Phone: Leslie 1. Aluminum The notice and supporting 94105, (415)974-8078, 2. Cyanide documentation also contains Ragle 3. Molybdenum calculritions and information regarding X. 1200 Sixth Ave.. Seattle. WA 98101. 4. Nickel risks from contaminants that EPA is Phone: (206)442-1225. jerry Opetz. 5. Silver proponing not to reRulate. EPA has Copies of draft health criteria, 8. Sulfate published nonregulatory Drinking Water occurrence, analytlcal methods and 7. Sodium Health Advisories on these health advisory documents wlll be 8. Antimony. Berylilum. Thallium and contaminante. .?ublic comment is also audilable for a fee from the National Vanadium requested scientific basis for 9. Zlnc on the Technical Information Service (NTIS). V111. Synthetic Omanic Chemicals: RMCb those ctilculations and whether EPA U.S. Department of Commerce, 5285. A. Availability of Analytical Methods should develop Primary Drinking Water Port Royal Road, Springfield, Virginia 8. Ropored RMCLs Regulations. or kleallh Advisories. or 22181. The toll free number Is eoO/336- 1. Acrylamide lake no action. 4700. local: 703/487-4850. 2. Aiachior Federal Register 1 Vol. 50. No. 219 / Wcdrcsdoy. November 13, 1985 / Proposed Rule8 - _. . - b 1. Al~licHrhAldiciirli ri4fnxltlc nntl Ixvel nnd which miiy have iiny tidvwsr: I\lllicniti wlfone c!ffecl upon the hi:;illh of pi:rwnn." 4. Cnrliofurcin 141 2(11)(1)I 5. Chlortliine U). MC1.s [ire the ~~iifori:i!ulhstiiiitloiil~ 6. I)iliromor.hloriiprcpiine 1. Slalulnry Requirements MCXn must tic! atif ;is closi: lo RM(;I.s ;iq 7. ti.. rn-l)ii:hlarot)enzene is fi!asi\h. Frvtsililr! mt:;rns "with Ihv iiw 8. cis. nntl tr~nr-1.2-l)ichloro1!thyl~nen The Siife Drinking WirIer Act (42 9. 1 .2.f)ichlnrriprop;inc of the hest ti:chnciliigy, trc:atrnc:nt U.S.C.3Wf. c/ .qt?q.) ("SDWA" or "lhe in. 2.4-0 Icchnicliies nnd other rniwnq. whic:h ttiv I Act") requires the KPA lo enlrililinh 11. Epichlorohytlrin A'dministrrilor finrls iiw xc:ner;illv p r imti ry drinking wii ler reguI n 1 ions 12. Ethyllienxenc riv~ilaIiIe(taking i;oRts inlo which: (1) Apply lo public writer 13. Ethylene dihromitlc con~idnriilitin)."Si*f:lion 141 Z[t)]!'l J. nyalemrc: (2) Apecify contamirianla which 14. I leplachlor Hntl I leplnchlor epoxide Even though R>Jf;l.siirv prcirniilq;itc~il. in judgmcnl of Adminintrator. 15. I.indiine the the no system in forced lo rc:tliic;c: in. Methoxychlor mciy have any edverne effect on the cimtaminanta lo this level or to tiikt! 17. Mnnoc:hloroticnxcnc henllh of pereone: and (3) npccify fiir otber action rc:g;irding cnnt;irniniints. 10. I'rilychlorina tctl Iiiphcnyla cnch conteminanl either [a) maximum 19. I'cntrichlaroph~:noI RMC1.n only nervi! ;is gii;iI.q for Iht! conlflminsnt.levels (MC1.n) or (b) Agency in the coiirse of sc!tting MCI.s 20. Styrene lreatment tcchniquce. See Section 21. Tiiliicne iind iirc thcrdorc inititil steps in the 42 3OOf. 22. 'l'cixnphenc 1401(1). U.S.C A trealment MCL rulemaking !hiit will follow. In lachnique rLquirc!rn$.it would be eel only 21. 2.4.s.~ nome cnses. the hKXs will Iw ui:t vwy if "it ia not economiccilly or 24. Xylenc CIOBClo the R,MCl.e: in other c;in!!n, C. RMC1.r Not l'rcipiineil technologically fcesible" lo aacerlnin nnelytical methodn. control proct:sai!J or 1. Alrrizinc the Icvel of ii conteminenl in drinking coel considpralions may dictale an 2. 2.1.7.R~l'clr~chlor1i1~i~,rnto-p-dioxin writer. sfC;ld lhnl is not RB clnsc. Public water 3. Endrin The SDWA includes provisione for syelems muel comply with the MCI.: 4. IIc~xrichlorolic!nscni! interim and reviaed regulatione. See non-compliance with an RMCI. ciinrilit 5. Simhzinc: ncction 1412,42 U.S.C. 3009-? Inle:im R. Other SOCn Ihc beaie of fln enforcemant ;ic.lion entabli8;led be IX. Impiicl of this Rt!giil;tliiin regulations were to be within dnyn of enactment (;Ithe under section 1414 of the Safc Drinking X. l~iililic1)ockc.t Waler Acl. XI. Rcqiieri Iiir l'~ilil,ii; Commitnl SDWA. Revined regulntions are lo he developed in IHOsteps: the Agency is lo Urt 01 Flpmand Tables .-.. . .. eslablish recomiriended ma-ximum II. Regulatory Framework Figiire 1-N;itiiiniil l'rimiiry IIrinkinR Weter contnminant levels (RMC1.n) rind thsn Issuing Revised I'rim;iiy Ilrinking ReRiiliitionn Rt!giihliiry lDriii:i!iliirc eslii Id inh mri xi mum con1ti miniin t Icvdn Wiiter Rtrgiilritionb is Ihc: ~i:i:~nOstr*~i in Tnlilc I-Rccrimmcnrltrtl Acliona on ANPRM (MCl.8) HS close lo the RMC1.s iis the evolution of tlii: primiiry drinking (:on ti1minrin tr fmnihle. MC1.s ;ire to ICproposetl ;it the wiitcr rcgiihtinns m;tnrl;iti:tl Iiy 1tw Tiilile 2-(hiili:lini!n nii tho IJw of lime of proniulgatinn the RMC1.s. Ilnccrtiiinty Fiictiirn of SfJWA. Tiilh .7--'rlirc!~!.(:litcgclr~Appri)iii:h for RMC'i,.q art?iton-enforceohle hrolth In the firsl stcp. thr: Niilioniil Intiirirn Setling RMC1.s piuIs. RMC1.s iire lo lie selkl H Icvd Primary Drinking W;itcr Ht!Riil;itions which. in the ~dmininlrfifor'ajiidgrnr:nl. T~lile4-l'rcliminiirv Cliiaqifiwitiiin of SOCa were promulgntr!tl on Decernh 24. 1!IiS. iind into 'Three Ciitcg~iryApproiich "no known or a n Iici p;it ed rid vi:rw: IOCn with an effeclive date of lune 24. 197;. Tiitilc 41\~tiia~ific:;itinn01 SOCs iinil I0C:s effects the henlth of pc.mons occur on Amendments werc: isawd in 197fb. 1Wt Iiiiactl iipon I'roponed EPA (;uitlclint!r iind which allows an iidi!(jii;iIt: miirgin of and 1980. See 40 C;PH Part 141. Titlile .S-R.MCI. Opliona fnr Ctitegfiry I1 nafety" Section 1412(11)(1)(n).Thc Maximum contarniniint levc:ls (\l(:l,sl conliiminants I louse Report on thc 1974 legislitlion Tiilile fbl)Topiineil RMC1.s for iind monitoring ;inti rr!porliny providen congmssiriniil guidence on Microorg;iniama rcquiremrmla wim: set fnr nurni:rou.s developing RMC1.s: Tali1e 7-In himRcRu Iti Iions: micrntiiologic:iil. incirg;tnic. orgiinic. ;inti Micriiorgiinirmn . . . the rc:commcntli!tl miiximiim Ii!vi!l miiqt rildicinucl idc con Iii rn inil n I J ( 40 CF'R I';i r I Tiit;lc &l~ropotecl RMCla fnr IOCr Iir! atrt lo prwcnt the iici:iirrirni;c (if nriy 141. Subpiirt 'f~ililc%-Short.tcrm An*cnsmentn for IOCr knciwn or cinticipritr!ti ritlwersr! cffitct. It milat n). for Which RMC1.n iire Priipi)retl inr:tiiili! tin ritleqiti~temiirgin of wf1:ty. iin1ma Section 1412(c)rif the SDWA ilircc.ti:tl Tnlile I&Short-trwn Annc!asrnc!ntn and Ihcre in no srifi! threahold for Icnntiiminiint. EPA to arrange! for thr! S;itinn;il Provirinnnl AADh lor IO(;n for Which In aiich H CHIC. the recommcndcd miiximiim Aciidrmy of S(:ir!nc:r!s (NAS) or ;in RMCla are not Proposed contaminant level shoiilil 1)e ail1 irt zcrii It.vel. t!cjiiiv;ilent organization to cont1iic:t ii Tiitile 11-Annlyticnl Mcthocla for IOCs 9.3-1185, 10. 1974. ~I~rlyto iisst!ss Ihe ht!;ilth t!fff!(;t!i of Tiilile .12--Froposi!cl RMC1.a tinil Ahl)la fcir tlouse Report No. July contnminiints in drinking water iinil lo s0Cn I'ropomad for Regiilalinn HI,20. In ndtlilion. B list of contiiminants providt! propos~lnfor RMC1.s. THtilc 1.3-Riak EstimHlea lor SOCr for Which is lo lie included in the reguliitions for hlii wcrt! Aviiilnhle "nny conlaminnnt the level of which An the .st?conr/st~p.sr!clion Ti~lile14-Shct-terrn Anstrrrmentr and ccinnot be iiccurirtely enough meiisurcd 141~(li~(l)(il)provided that EPA must I'rovirionril AADls for SOCn for Which in drinking water 10 csliiblish H propriw: nnd promiilgitte N;ilion;rl RMCl,s we not Froprisrtl Rccommcnded Mri ximum Cont ii m iniin t Rsviscd Prirniiry thinking Wiiter

I

F4701 rev. 6-14-85 48938 Federal Register / Vol. 50, 219 / Wedneeday, Novembor 13, 1985 / Propoeed Rulee - No. Regulatlons (NPDWR) that would community ayeteme eewe a transient Include RMCLo, MCLo and monitoring population fa8 oppoeed to residential). and reporting requlrements for those Only thoee MCLe In the Interim contaminante that may have any Regulatlons thought to have potentially arlverae effect on human health. acute health concerne were applied to Dcvelopment of the NPDWR will be the non-community eyeleme; theae accomplinhed in four phaees: Included total coliforme, turbidity and Phane I Volatile Synthetic Organic nitrate. Chemicnln. RMCLe were not eatabliehed in the Phaee IJ Synthetic Organic Interim Regulatione becauee the SDWA Chemicals, Inorganic Chemicals and only specifies that RMCLs are to be set Microblologlcal Contamlnante. in eetabliahing the Revieed Regulations. PhaaeIIA Fluoride. The MCLo in the Interim Regulations Phase 111 Radlonuclldee. were to: Phaee IV Dlainfectant By-Ptoducte I-- lRCL ?ROm¶AL Including Trihalomethanee. 1I "protect health to the extent feasible. usinn This notice la Phaas Il-propoeal of technology, treatment techniques. and other RMC1.n for certain inorganic. organic meann which the Administrator determines are generally available (taking costn into Rnrl t~iologlcalcontamlnanls. Becaune of connidsration) on the drte of enactment id the great number of posnible 8UbRhnCe8 this title..' Section 1412(a)(~) to be considered. additlonal drinking water contaminante from theee three Thia mandate for Interim MCLs in groups will be coneidered In later similar to the MCLB in the Revieed iterntione of NPDWR. Regulatione; however. the Revised In general. the procedure for all four Regulations are different in two phancq wlll be slmilar as Is shown In fundamental respecta. First. in the Figore 1. Generally. It requires Revieed Regulations. a goal (Le.. the approximately one year for each major RMCI.) is eatabliehed and then the MCI. regulatory action (e.e., RMCL to is net a8 close to the goal tc~:3 feanihle. proporal). The statue of each Phase is RMCLe are to be eatabiiahad for a provided below: comprehensive number of contaminants. Phasel: This proposal dealn with the RMC1.s. Second. in netting MCLB. feasible in ANPRM. March 4.1982 47 FR 8350 defined in the SUWA a8 using the /JftSl Public kleetlng. April 28.1882 Ill. Regulatory Background femphaeis added) technology. treatment Four Public Workshops, June-August The discuseion in thie section techniques. and other means which the 1982 provldes a brief overview of: (1) The Administrator findn are generally RMCI. Proposal. lune 12,1984 49 FR hterim Regdotione hnd the available (taking coets into 243.30 implementation experiences. (2) the coneideretion). Final HMCI. rule/MCL Propoeal. National Academy of Sciencen (NAS) B. Notional Acorhmy nf Sciences (.VAS) Cchcduled for October 1985 role in development of the Revined Re~uh~tione.(3) area9 that will be 1)ha.w 11: Under the SDWA. NAS in charged addreseed in the Revined Regiila tinne. with aeseeaing the following: Micro! iological Workshop. December 4, and (4) Summary of comments on the Phane 11 ANPRM for theee Summarylevaluation of relevant 19R1 publications and etudies. ANPRM. October 5.1m 48 FR 45502 contaminante. Methodo~ogien/aaeumptioneused in Four 1)idAic Workshops. September- A. Jiilmim Regulations eatimating levels at which adverse I)iw.ml)er 1983 An required by the SDWA. EPA acted effect8 occur. Pul)lic. MeetinR. Dccember 13. 1983 quickly followinq he panea~eof the Methodo~ogien/aes~~mDtionsfor Finel HMCI. nlle/MCL Proposal, SDWA in publishing Interim Primary estimating margin of safety for drinking Sc.hc*cluled for October 1988. Drinking Water RcRulations. Regulations water regulationn. Phase HA: were established initially for ten Develop propoealn for RMCLe. Inorganic chemicals. eix pesticide8 and . Noticc. December 1.1981 48 FR 58345 List of contaminante the level of two microbiological Indicator which cannot he determined in drinking ANPRM. October 5. 1983 48 FR 45.W2 contaminants. Amendments were later water that poee a health risk. added on radionuclides. RMCI. I'ropoaal. May 14. 1985 50 FR Research priorities. u)l fi4 trihalomethanes and corronion/sodium monitoring. The regulatione eel MCIa. While the NAS did not provide Final RMCI./MCI. Proposal. Scheduled propoeals of RMCLo. the NAS has for November. l9A5 monitoring and reporting requirements. Analytical method8 were specified a8 provided guidance on the above items Phase 111: well a8 public notification requirements and on the toxicological effects of Radionuclide8 Workshop. Mey 1983 (SO FR 59588, Radionuclides. 44 FJ7 numeroue drinking water conturninants. The five volumee of Drinking Water and ANPHM. October 5.1983 4fl FR 45502 68841,45 FR 57332). Theee regulations apply to some Health include the following: RMCL Proposal. Scheduled for 8O.OOO community water systems and Volume I(Is~) December, 1985 18o.OOO non-community water eyetems. Phase IV, ANPRM Scheduled for The dletlnctlon between community and Safety and risk assessment 1R88 non-comrnunlty systems is that non- procedures. S-074999 00~R(02Mt2-NOV-BJ-IJ:I4:22) F4701 rev. 614-85 Federal ReWer 1 Vol. 50, No. 219 / Wednesday, November 13, 1985 / Proposed Rules 48939 - Toxicity of organic. inorganic, comments received on the ANPRhl are Strength of Evidence of Potential microbial and radionuclide discussed in this section, Part D. Health Effects contamirQants. This proposal addresses only the Because of the added costs of Volume II (1080) selection of conlamioants for possible regulation and the proposed RMCLa for treatment. many systems remain out of Disinfection of drinking water. these substances. Public comments and compliance with several MCLs; some Chemistry of disinfection in workshop results addressing MCLB and systems remain unconvinced that the drinking water. monitoring and reporting requirements net benefits of contaminant reduction is Granular activated carbon. will be addressed in the MCL proposal worth the COBIS. This issue often rdalwi to the availability and strength of Volume 111 (1980) which will be published with the promulgated RMCLB. However, to evidence of data on potential health Epidemiolo studies. provide some perspective on approaches effects. Problems o Prisk estimation. being considered for the regula'i, ona. a Comprehensive assessments have Toxicity of selected contaminants. brief overvicw of problems that will be been conducted of the available Nutritional aspects of drinking considered in the development of the information on potential health effects water contaminants. RMCLs. MCLB. and monitoring and of every contaminant in this proposal. Volume IV (lSa2) reporting requirements is provided State-of-the-art scientific methods have below. been utilized in determining the Dis!ribution system potential health potentinl health effects. All of the problems. Implementation of the Interim Regulations has shown the following accumulated/analyzed data are Toxicity of inorganic and organic summarized and presented for public chemicals. maior areas of concern: Compliance by Small Systems comment in the Health Effects Criteria Volume V (1883) For the moat part, compliance Documents referenced in Section X of Toxicity of selected contaminants. problems with the MCLB and monitoring this notice. Epidemiology of arsenic and and reporting requirements have Monitoring Inflexibility asbestos. generally been associated with small RCCZILIBCthe NAS did not provide systems. Resources are often limited in The 1ntef;m Regulations require proposed RMCLs. the Agency h~s small systems and when a drinking monitoring to as9898 compliance with devehped the proposed RMCLs in this water p;.oblsm iR present. the small the MCLs at set frequencies for certain notice based upon its own cvaluations sytteins gcn*:rill!y are least able to cope contaminants: for example. monitoring which included the NAS reports along with it. for inwganic compounds must be with other pertinent data. Variances may bc: grwtcd when a conducted at least once per year or once system. "because o! r~aractcri9tir.sof per three years for supplies using C. Issues Being Addmssed in Revised the raw water sources which are Jurface or ground water sources. Regulations reasonably available to the systerns. respectively. While monitoriq once a As directed by the SDWA. the cannot meet the requirements . . . year or every three years does not seem. Revised Regulations will address a wide despite application of the heat to be overly demanding. this can be variety of problems in drinking water technology. treatment techniques, or costly for small systems. and upon those quolity in public water systems across other means. which the Administrator States that conduct monitoring for the United States. Much experience has finds are generally available (taking certain of the systems [e.g.. small been gained from the implementation of costa into consideration)." (Section systems) within their boundaries. States the Interim Regulations and a 141S[a)(l)(Al).Variances do not have a have reported that certain of these comprehensive review and revision of fixed date in the law for the system to inorganic compounds have not been the provisions of the Interim Regulations come into compliance but the system detected at significant levels in the is being undertaken during development must be put on a compliance schedule drinking water in many systems and the of the Revised Regulations. In addition, requiring compliance as expeditiously as probability of future contamination is new problems in drinking water quality practicable. very slight. Monitoring has shown that have bren discovered that will be The approach to variances in the little change in concentrations occurs addressed in the Revised Regulations. Revised Regulations would be similar to over time for certain contaminsnts. Under the requirements and dennitions that promulgated for the trihalomethane primarily inorganic- in ground water. irl of the SDWA. the basic questions being regulations (48 FR 8408. Feb. 28.19R3). addition. some contaminants such its thft considered in the efforts include: The best generally available technology six pesticides in the Interim Regiil;itions For which contaminunts should (GAT) under section 1415 would be have been found only rarely since regulations be set? defined for each regulated contaminant. compliance monitoring requirr!mr:nts What levels for the RMCLs and taking Cost into consideration and went into effect. MCLs would be appropriate? possibly categorizing by Bystem To provide for more efficient use of What monitoring and reporting characteristics such as size or water State and local resources. flcxibility in requirements would be appropriate? source. States would evaluate each crtse monitoring requirements will \le H The Advance Notice of Proposed on a site-specific basis to determine if general principle in development Of thr! Rulemaking (ANPRM). issued October 5. the identified GAT was appropriate and Revised Regulations. In addition. to 1884 (48 FR 45502). provided the public effective for that system. In addition to assure detection and control of with an opportunity to review the issues central treatment alterna tives. intermittent contaminants or those thnt and comment to the Agency early in the decentralized options euch as use of are not distrihuted homogenously. more development stages. The ANPRM was bottled water and point-of-use treatment specific monitoring requirements will tJI! followed by four public technical devices are being considered as control designed. States also will be provided workshops and a public meeting during measuree to reduce contamination until authoriiy to determine specific which the regulatory and scientific the system can reach compliance with monitoring frequencies for systems issues were discussed. The public the NPDWR through other means. beyond the federal minima. A three-

SO74999 0039(02)(lZ-NOV-RJ- I S:t4:24) F4701 rev. 6-14-05 46940 Federal Register / Vol. 50, No. 219 I Wednesday, November 13. 1985 1 Propoeed Rules

tiered approach is heing considered for e.g.. corrosion by-products or portions of wi!l be re-evaluated along with a determining whether and in what a system using o specific well, well field. number of other inorganics that have manner to regulate specific or surface water source. If results are been detected in drinking water. Some contaminants. Contaminants would be averaged, the overall system may be of these include arsenic. barium. nitrate. divided into three categories: technically in compliance and thus no ritrite. copper, sulfate. asbesto9. and Tier /-Those which occur with action (including no public notification] sodium. sufficient frequency and which are of would be required. However, those The microbiological quality of sufficient concern to warrant national consumers in the particular probleni drinking water continues to be a regulation (MCIa) and co;lsislent portion of the distribution system are principal concern in development and monitoring and reporting. exposed continually to levels above the eventual implementation of the Revised Ticr I/-Those which are of Sufficient MCb. Similarly, corrosion by-products Regulations. Despite compliance with concern to warrant national regulation (e.g., lead) are dependent upon the the Interim Regulations by most water (MCI.R)hut which occur at limited or corrosive characteristics of the drinking systems. waterborne outbreaks of prcdictnI)le frequency. justifying flexible water and the distribution syslem disease are reported with increasing nationnl minimum monitoring materials; monitoring may not detect frequency. Much of this may be requiremcnta. any violations of MCLe if not sampled at attributable to better reporting Ticr Ill-Those which would not the proper locations. Sampling wrirrnnt development of a regulation procedures. Major causes of outbreaks but techniquqs also can impact on the level are deficiencies in (or lack of) treatment for which ron-regulatory health of contamination detected. as well as distribution system problems. Ruidance could be provided to States or These are areas of significant concern The specific etiology of the outbreaks is water syslemo. end the Revised Regulations will for the most part unknown: Giardia Additional dcbsriplions of the determine the most effective means of has been identified a primary cateRories can be iwnd in the ANPRM fambia as calculating compliance. Monitoring agent in many recent outbreaks in all (Ocl. 5. 1983, 49 45502). requirements will be redesigned to parts of the country. Viruses a!so have Public Nolice assess more effectively the occurrence been implicated in a large number of of corrosion by-products and human outbreaks. Controls on coliforms and The SDWA is very specific in the area exposure in various parts of distribution of public notice (Section 1414). and turbidity alone, although highly systems. effective. are not always sufficient to public notification requirements in the Other areas of concern that will be Interim Regulations are relatively asbure the biological safety of drinking eddressr in the Revised Regulations water. inflexihle. The specific media are stated include: in the law and regulations: however Numerous synthetic organic D.Public Comments these do not appear always to be the chemicals (SOCs] which have been most effective means of notice. The The ANPRM (October 5,1983.48 FR found at increasing frequencies in 45W2) solicited comments on the SDWA currently is under review for drinking water across the country. possible amendment in the area of technical and regulatory iesues that are Essentially. two separate groups of being examined concerning the public notification to allow some SOCs are being detected. flexibility. development of National Revised -Pesticides. Difierent pesticides have Primary Drinking Water Regulations for Non-Community Water Systems been detected in drinking water in organic, inorganic, and microbial Non-community water systems various parts of the country. The contaminants in drinking water. See (NCWS) serve transient populations as extent of the problem is highly Appendix A for a summary of the public opposed to residential. Only three MCLe dependent upon the pesticide comments received. application mode and hydrogeological in the Interim Regulations apply to IV. Regulatory Alternativea NCWS and these protect against acute factors. Pesticide contamination of health effects. Concerns have been surface waters appears to be closely Either of two philosophies could be raised about reported human exposure related to such factors as rates and followed in determining which to contaminants in certain types of times of application and rainfall and substances are appropriate for NCWS, such as schools or factories run-off. Thus. monitoring results can regulstions under the SDWA. The which cor sistently serve the same be misleading if sampling is not done broader view would establish RMCLs consumers. In addition, monitr-ing at appropriate times and places. and MCLe for as many substances as frequencies were similar for all sizes of -Organic Chemicals (industrial uses). possible that may be of henlth concern NCWS regardless of :he number of Concern 1s focused primarily upon in drinking water. RMCLa and MCLe consumers served per day. contaminetion of ground waters from would be set for substances on the basis The Revired Regulations will address improper disposal of hazardous of (1) sufficient health effects these two situations by considering wastes; numerous SOCs have been information and (21 the occurrence in redefinition of NCWS and possible detected in ground water as well as in drinking water or the potential for more application of other MCb with potential surface waters although introduction widespread occurrence in drinking chronic health concerns. In addition. of controls to induatrial and municipal water. monitoring requirements will be effluents apparently has improved A more limited view would be to evaluated according to the size of the surface water quality in recent years. entablish RMCLe crnd MCLe only for NCWS and other relevant factors. Inorganic chemicals have been those aubstances which actually occur found to be problems primarily in irr public drinking water supplies at or Monitoring and Determining ground waters and are usually a result near levels that could result in sufficient Compliance to Accurately Detect of natural contamination by geological public health risk of national scope from Contaminants formations. In addition. contamination drinking water. The limited view would In certain systems, problems with for hazardous waste site run-off and not examine the potentla1 for exceeding MCLe are experienced leachates remains a concern. All widespread occurrence in drinking continually by n portlon of the system: lnogenlcs In the Interim Regulations water and thus would not incorporate

w4999 00(0(02)(l2-NOV-IS-IS:l4:26) F4701 rev. 614-85 Federal Register 1 Vol. 50, No. 219 1 Wednesday, November 13, 1985 / Proposed RuleP 48941 -- - -- an approach for long term anticipatory reqursted to provide advice on the every chemical tha I may appear in protection of water supplies; it would general philosophical app-oach to drinking water and that theoretically essentially wait for widespread determining which contaminants should may adversely affect health in some contamination to occur before be selected for regulation: the Council remote Circumstances. What is needed regu1ato.y action would be taken. rcommended the following: is some priority of contaminallts for Tne strength of the broad view is that The Council recommendn that regulation adversely affect health in it would provide a single, txtenslve contaminants be considered for regulation on some remote circumstances. What is listing of concentration limits that had the basis of sufficient health effects needed is some priority of contaminants been thoroughly and publicly reviewed infornatim and the occurrtnce of for regulation so that a reasonable and that would help to define "potable" contrtminants in drinking water and the number of contaminants of sufficimt drinking water regardless of source. The potential for more widmpreud occurrence in concern can be addressed in rcqulations drinking water. presence of such a listing may assist that will advapce the g03lS of the response to many situations involving The minority felt that contaminants should be considered for reRulation on the hssi9 of SDWA and r;ovide definitive quidanrx contamination from many infrec,dently sufficient health effects ipformation and the to address pctential human health detected substances. Since decisions to potential for Occurrence in drinking water. It effects el exposure to hazardous act or not to act must bo made for every wan contended that tI:e airr. cf the Safe maknals in drinking "ater. To contamination incident. this anticipatory Drinkin8 Water Act is to prevent the accomplish this. EPA could adopt and comistent approach might be the occurrence of contaminants in drinking water criteria from which to select most coat/effective. avoiding cam-by- and waiting to remlate until the contaminant conteminants for possible rqulatim case decislons on the safety of the has been detected is not an approach considered to be protective of public health. under the SDWA. The most relevant drinking water. One additional criteria for selection of contaminants consideration is the intensity of public The approach followed in this are: [I)The.analytical iibili*;. t(~deti8r.t il interest and awareness that some proposal in the broad view that would contaminant in drinking hater. (2)the chemical might be in drinking water, the Bel RMCLa and MCls for conIamir,ants potential health risk. and 13) thc public wants to know if the drinking of health concern that have been occurrelice or potential for occurrence in water is safe: a federal standard detected in drinking water or have the drinking water. provides guidance on this question. potential for more widespread /L set of selection criteria have bee:, Another situation where regulation occurrence. Public comments are developed which essentially expand the may be appropriate under the broad requested on the appropriateness of this three primary iactors listed above. Use view is for a chemical that has only apprc ach. of a specific formula to app!y selectinn been detected [in surveys condilcied to V. Factors in the Development of criteria is not believed to be appropriate date) at levels below those associated because the many variables with potuntial health risks. The MCL RMCLs of The SDWA authorizes EPA !o associated with contaminants in would provide guidance that no action drinking water: however. a decision- was necessary for these systems with establish RMCLe for "eP,ch contaniinant less than that level; without regulations. which. in [the Administrator's] judgment making "logic train" has been developed these types of situations have met . . . may have any adverse effect on the which incorporates thc selection criteria widely varying responses by Stales and health of persons". Section 1412(b)[l)(B). and provides a framework from which public water systems. Regulations can A primary drinking water regulation is to make appropriate determinations. provide a basis for rational and uniform to be established for each contaminant Civeii the variability associated with responses to incidents of contamination. for \. hich an RMCL is established. exposure and human health aspects of The second, more limited approach to Section 1412(b](2).hesented below are drinking water contarninants and the standard setting has the strength of discussions of (1) the factors used to directives of the SDWA. the decision allowing EPA to concentrate its select contaminants for regulation and criteria must remain flexible such that a resmmes on those substances ~t~~~..~(2) the methodology and basis for case-by-case decision can be made for pose the greatest public health risks determiring what levels are appropriate each contaminant. However. the from drinking water, reflecting both for the RMCLs. decision criteria do set forth an extent of contamination and the size of operative framework. For each populations at risk. Thus. the formel P. Selection of Contaminants for contaminant. the essential factors in the regulatory process would be reserved Regulotion analysis are as follows: for the most significant current This section provides a discussion of Is an analytical method available to problems. States or other entities would the factors used to selpct the specific detect the contaminant in drhking be forced to address contaminants of contaminants for which RMCLs are water? If EPA cannot ascertain whether more limited scope. This approach proposed at this time. SOCs. lOCs and the contaminant can be found in would likely lead to a multiplicity of microbials that were not included in this drinkitig water. a regulation may nat bc State regulations and the need for a proposal will be reconsidered in later appropriate. large number of non-regulatory EPA iterations of the Revised Rcguations as Are there sufficient health effects Drinking Water health advisories to fill additional data become abailable. The data upon which to make a judgment on the gap. Health advisories can be reader also is refe;red to the RMCL an RMCL nr health advisory? prepared more quickly by EPA because proposal for VOCs (49 FR 24330) for Are theta potential adverse health they are limited only to considerations additional discussion on which factors effects from exposure to the of toxicology (they do not consider are considered in selecting contaminmt via ingestion? technology feasibility and costs) and contaminants for regulation. Does the contaminant occur in they would not require rulemaking. On Other than the above directive of the drinking water? the othrr hand. health advisories have SDWA. little additional guidance was -Has the contaminant been detectetl in been adopted by some States as de facto provided upon which to determine how significant frequencies and in a standards. to select contaminants for regulation widespread manner? The National Drinking Water under the SDWA. Obviously. it is -4f data are limited on the frequency Advisory Council [NDWAC) waa impossible to consider for regulation and nature of contaminaticn. is there

S-074999 m4 t(O2M12-NOV-85-I5:t4:2~) F47m rev. 8-14-85 I

46942 Federal Register / Vol. 50, No. 219 / Wednesday, November 13, 1985 / Proposed Rules -- ~a significant potential of drinking health effects also considers the methods used have been developed only i w u t er con t a m i n ii t I on? International Agency for Research on recently and quality assurance programs Ewh of these csseiitial factors is Cancer (IARC)criteria and thP EPA only recently have been a priority discussed brlow. proposed guidelines for carcinogen risk concern. Thus. existing data from past Arro/j.tico/ Met?rhotls.Annlytictrl trasessnient. 1:i the absence of potential surveys may be questioned. In general. nwthods must be avnilable such that the carcinogenic risks. most estimated If a positive result is reported at a t priwnce of the chemicals in water cnn allowable exposure levels will be certain conceptration, it can be assumed lii! vcilitily determined and quantifiild considerably higher than usually found that the contaminant was in the sample within HCCCPIH~IC limits. If the. level of a in drinking water. but the level could be questioned. contiiminant cannoi be accurately Occurrence in Drinking Water. However, it cannot be said with rnough meosured to 9-1 Hn RMCI, the Consideration of occurrence data confidence that if a sample was c:ontnminnnl in lo be listed. SDWA encompasses the frequency of negative. the contaminant was not there. section 1412(h](l)(B).This factor is also occurrence. the level of occurrence and Of course. detection limits are also a iin impcrtanl piirt in determining the extent of the population exposed. An significant limitation. whether the suhnlnnce ctrn be regulated examination of the available data with The extent and quality of the 1i.e.. whcthcr the contominant can be regard to how well it represents national available data varies for each of the found in drinking wuter) and whether an occurrence Is carried out. along with an contaminants under consideration. MCL oi JJ treatment technique regulation evaluation of the quality of the data. Thus. EPA ususally must base its should lie promulgated. I'he SDWA EPA has conducted a number nf decision on appropriate regulatory staten that MCIs ure approprinte if "it is national sampling surveys to assess action (or no action) for certain economicaliy and tcchnologicelly occurrence of certain contaminants In contaminante on an imperfect data set. feasible to ascertain the level of such drinking water across the country. In In evaluating occurrence data. the co.nterninant in water in public water addition. a number of States have most significant alrpectn are frequency nyrtems." SDWA section 1401. If not. a conducted surveys of public water of occurrence and the widespread (or treatment technique is to be specined. systems for certain contaminants, These limited) characteristics of the A number of factors nre taken into surveys constitute the beat sources of r~ntamination.Because of the consideration in evaluating if analytical available data oii occurrence of limitations In the survey data (noted methods are available. including such coiltaminants in drinking wzte:. previously). levels of contaninat ion that

factors as: However, limitations of this information have been detected are not belie\ 1.i to Method validity (reliability). for certain contaminants are notable: be necessarily representative of the Snmpling techniques and Extent of sampling and sampling quality of drinking water in all supplies prepi rntion including volune of ample, sites as being representative of national across the country. Many of the preacrviition. and time of Iransporl. occurrence. contaminants In drinking water are Luborntory experience/availability/ -EPA surveys conducted to date all man-made synthetic chemicals whose capahilitics. have been limited to some extent by presence in drinking water indicates I'rccivion and accuriicy. resource constraints. The surveys that a pollution incident has occurred. Detection limits. have not been statisticslly The levels detected to dale may or may Costs of analysis. comprehensive such that complete not be representative and levela may The reliability of analytical methods knowledge on the extent of potential change due to pollution incidents. Levels used for compliance monitoring is contamination is known. for natural contaminants in ground criticnl for detcrmininp.the MCL.The -States are more limited in extent of water are generally more representative iiccuracy (lack of hias) and precision sampling. While a few States have and would not be expected to change. (good reproducibility) of the analytical conducted comprehensive surveys for Thus. because of the imperfect methocis is evnlualed in order to certain contaminants, most States knowledge on the levels of deterniinc whnt are reasonable levels of have not. Reliability of these contamination, frequency of occurrence performance by aIialytical laboratories analytical data is usually unknown. is a more important factor than levels of at levels connidered for the MCla. This --Surveys usually are conducted one occurrence in decisionmaking regarding cveluation is ciirried out in order to sample at one time which may not for which contaminant standards should ensure that masonable performance assess reliably the variations in be set. Therefore, data are evaulated for expectations for those laboratories surface water quality or variations in frequency of occurrence, population which will be performing the actual ground water quality due to pumping exposed and the widespread (or limited) annlysin is considered. instead of an patterns. nature of contamination problems. A analysis based upon a single. best -Also. surveys of ground water judgment is made for each contemincnt lnboralory situntion which is not systems are seldom of every well in a based in part upon these factors. representative of real world situations. system and some samples are taken in The ideal data base would provide an Itealth L'lftxts. Consideration of the the distribution systems rather than at estimate of the number of public water potential health effects of a chmical the well head. systems with contamination problems encompapses the (1) suitability of the surveys analyzed for a limited and population exposure and the nvailahlc data for assessing the toxicity number of contam!nanta. For both EPA widespread or limited nature of of the chemical and 12) the possibility of and State surveys. a targeted list of contamination problems across the human health concern from exposure in contaminants is the basis for analysis. country. Where comprehensive data drinking water. The human health Many contaminants thus have not been such as these do exlst (and human concerns relate lo acute and chronic looked for. exposure to the contaminant may pose toxicities. carinogenic effects including Reliability of resultant data (quallty an adverse effect on the health of effects in animals or humans. and other assurance. limlts of detection). ersona). this is the primary decision toxicological concernn such as whether Analysis of SOCs and pesticides !actor in determining if a regulation or not a contaminant 1s a mutagen or requires sophisticated techniques using should be set for a certain contaminant. teratollen. Assessment of these potential hlRhly eensltlvr! instruments. The This decielon factor le a judgment that

I F4701 rev. 6-14-85 ! I Fedoral Regiater / Vol. 50, No. 219 / Wednesday, November 13. 1985 / Propoaed Rule8 46943 - .___ -- - -_ 1' the contaminant occurs In drinking characteristics of the use of a Synrhetic Oeonir: Chc.nricciIs,~I'c.stir/tl#-s water with sufficient frequency to contaminant and the locations of that include in Reviaid Rcguletions: warrant national regulations. No use that would contribute to potential guidance on what constitutee a Widespread contamination problems in Acrylemide sufficient frequency for regulatory drinking water. Alachlor action was provided in the SDWA. but (7) Production Rates. An assessment Aldicarb frequencies of leas than one percent of of the amount of contamhant being Carbofuran systems (i.e., lees than 500 systems) produced annually to assess if the Chlordnne could certainly be sufficient. Thua, potential exists for significant cis-l .Z-Dichloroelhvli!rrc. regulations may be appropriate even contaimnu lion. Dibromochloropropiinii where the frequency of occurrence was While the above factors are listed in ort ho-Dichlorcil)enzenr! very low if the contamination problem priority order. the last four factors 1.Z-Dichloropropani! was found in different parts of the generally are examined collectively to 2.4-D country or In various regions of the assees the overall potential for drinking Epichlorohydrin country. water contamination. Ethylbenzene Potential for Contamination of From the list of InL.ganic. synthetic Ethylene dibromidc Drinking Water. For contaminants that organic chemicala/peeticides and Heptachlor have been detected in drinking water microbiological contaminants in the t teptachlor epoxide but for which data are limited, an October 5, 1987, ANPRM. contuminrinte Lindrine analysis of the potential for Widespread have been selected for Inclue!on in the Methoxychlor drinking water contamination le Revised Regulations. Available data on Monochlorobenzena conducted. Factors considered in this each of the chemicals on analytical Polychlorinated 1)iphcryls anaryala in order of importance are the methods, health effects. occurrence and Pentachlorophenol following: potential occurrence were evaluated Styrene (1) Occurrcnce in Drinking Woter using the selection criteria and Toluene Ofher Than Community Water Supplies. framework outlined above. Table 1 Toxa ph ene Certain contaminante have been summarizes the recommended trans-1.Z-Dichloroe t hylenc detected in private welle but not In regulatory or non-regulatory action for 2,4.5-TP public water systems. usually because each contaminant in the ANPRM.- Xylenes , . ., .. . . . of limited sampling program. For the . most part. this factor deals with Table 1.-ANPRM IOCs/SOCs/ Develop t iealth Ad rpisories: pesticides which have been detected Pesticides Recommended Actions Atrazine during certain studies of pesticide usage meta-Dischlorobenzene and drining water contamination. Inotgonic Chemicals Dioxin (2.3.7.8-TCDL)) (2)Direct or Indirect Additives. Include in Revised Regulations: Endrin Numerous conlaminante are in drinking Arsenic 1 lexachlorobenzcne water as a result of direct addition as a Asbestos Not included in Rcrviaed Regulations water treatment chemical or Indirectly Barium nor is EPA developing tlealth through such actions a5 leaching from Cadmium Advisories at the present time. EPA will pipc coatings or corrosive actions on Chromium evaluate later. piping materiels. Pesticides registered Copper Adipa tes for use in or around drinking water fall Lead Dalapon into this category. Mercury (3) Ambient Surface Water or Ground Dibromomethme Nitrate Dinoseb Water. Contaminants detected in 1 Nitrite Diquat surfacg waters or in ground waters I Selenium Endotball through various water quality surveys or I In sampling around hazardous waste Develop tlealth Advisories: Glyphosate sites have the potential for Molybdenum Hexachlorocyclopentadicne I Polyaromatic hydrocar1)ons contaminating drinkin water. Nickel I (4) Present in Lipuijor Solid Waste. Cyanide Phthalates Contaminants known to be in Industrial Sodium Picloram i Simazine i or municipal wastewater effluents or in Sulfate i waste ponds or known to be in solid Silver 1.1.2-TrichloroethHne waste being dieposed in landfills have Not included in Revised Vydate 1 the potential to migrate to drinking Regulations, nor is.EPA developing Microbial Contaminants 1 water intakes. Health Advisories at the present time. d (5)Mobile to Surfoce Water {run-off) EPA will evaluate later. Include in Revised Regulations: or Ground Water (leaching). The Aluminum ToIHIcoliforms phyaical/chemical characterletice of Antimony Turbidity contaminante are examined to Giordio determine their potential for movement Beryllium Viruses Thallium to a drinking water supply. This is Deidop tiealth Advisory. essentially an analyeie of the fate and Vanadium I transport of contaminants looking Does not currently appear to be a Legionello lj toward the potential for contamination need for an RMCL or Health Advieory. Monitoring for tteterotrophic Plate of drinking water sourcee. Will examine In future If data warrant Count will be Included within (6) Widespread Dispersive Use reconsideration, compliance monitoring requirements for Patterns. "hie evaluation neseeses the Zinc total coliforms. I 5-074999 0043(02Wt2-NOV-8S-I5:14:32) F4701 rev. 8-14-85 - 46944 Foderel Regleter / Vol. 50, No. 219 / Wednesday, November 13, 1985 / Proposed Rules

B. Soutre.c of Occurrencr and tiurnan have been conducted by ODW since C. Evaluation of thdth Effects and EX~ISII~VUoto 1975. These include: Determination of RMCLs National Orpnics Reconnaibsance UHh m the occurrexe of synthetic For those contuminants that "mtly orgunic chemicals in uir. food and Survey (NORS). have any adverse effect on the health of drinking wuter have been assembled Nationul Organics Monitoring persons" (for which analytical methods Survey (NOMS). from numerous published reports and are available). RMCLe are to be 9el at tl supplemented by federal research National Screening Programs for level which: studies und rcaults from federal and Organics in Drinking Water (NSP). Community Water Supply Survey no known or anticipated adverre effocls on nliiti reRulatory activity. The resulting (CWSS). the health of pereon8 occur and which allowr RummHries provide a view of potential of Rural Water Survey (RWS). nn adequate margin safely. Section tiurnan exposure indicating the relative 14wbl( ~Il~llBl. exposure of each source of intake. These Ground Water Supply Survey (GWSS). Summarized below are the approaches data are then factored into the to NORs was conducted in 1975 to I used determine the RMCh for non- determinstion of the RMCL tls the determine the level of six SOCs in 80 carcinogens and carcinogens. Additional RMCL munl consider intake from all discussion is provided in the Phase I sourcw not just from drinking water. cities acrow the country. These water supplies served 38 milliontndividuale. (Volatile Organic Chemicals) RMCL Food diita, when available, come largely proposal (%e 48 24330). from compliance studies conducted by NOMS. conducted in 1978-1977. extended EPA's knowledge on thc 1. Non-Carclnogena-AADIs the U.S. Food and Drug Administration. occurrence of volatile organic The markct baRGet studies and compounds In drinking water. One For toxic agents not considered to coinplirince program reports provide hundred and thirteen cities using surface have carcinogenic potential. "no effect" duta on residue levels of selected water were included in this study. levels for chronic/lifetime periods of chemicals in grain and vegetable crops, NSP. Conducted between June 1977 exposure including a margin of safety fish tissue. food animal tissue, spices and March 1981. provided a broadened are referred to commonly as ADIS or and other products. FDA total dietary examination of SOCs in drinking water. Acceptable Daily Intakes. These AD18 studies for adults. infants and toddlers The cornpounds sampled included 23 are considered to be exposure levels were used when available. The majority hydrocarbons. 8 aromatics. 22 etttimated to be without significant risk of these data were developed during the pesticides. phenols and acids. One to humans when received daily over a 1970's. Data developed by USDA on hundred end sixty-six water supplies. lifetime. residue levels in meats were used to mos;ly using surface water, located in 33 The intent of a toxicological analysis supplement existing knowledge os were States participated in the study. is to identify the highest no-observed- duta from specific studies covering Two different CWSS aludies have odveree-effect-level (NOAEL) baaed limited areas of the United States. been conducted. The le69 CWSS upon assessment of available human or Data on the level of pesticides in air provided !nformation on the level of animal data (usually from animal were developed by the EPA Office of inorganics in drinking water. Over 950 experiments). To determine the AD1 for Pesticide Programs and predeceneor cities throughout the United States regulatory purposes, the NOAEL is organizations. Air sampien were participated in the study. A second divided by (an) appropriate cdlccted in 1970-72 PIsites in 18 U.S. CWSS was conducted in 1978 providing "uncertainty" or "safety" factor(a). This cities and examined for pesticide information on both inorganic and process accommodates for the content. Data on the level of non- volatile organic contaminants. extrapolation of animal data to the pesticide organics iv anibient air were The RWS was conducted in 1978 to human. for the existence of weak or extracted from a rcport for the EPA exominc the quality of rural water insufficient data and for individual Office of Air and Radiation (Brodzinsky, supplies. The level of both inorganic end differences in human sensitivity to toxic R. and Singh. H.B. 1882. Volatile Orgapic volattle organic contaminants was agents. among other factore. Chemicals in the Atmosphere: An determined for over 800 samples. ADIS traditionally are reported in mg/ Asncaement of Avrtilable Data. Prepared The GWSS. focusing on ground water kg/day but for RMCL purposes. the "no by SRI International. Menlo Park, supplies was conducted in 1980-1881. effect" level needs to be measurable in California. Office of Research and lhie study provided information on the terms of drinking water quality, Le.. mg/ Development. U.S. EPA Research occurrence of 34 SOCe in nearly 1.000 liter. An adjustment of the AD1 to mg/ Triangle Park. North Caro!ina. Contruct water supplies. liter is accomplished by factoring in an No. 68-02-3452). Gate from individual In addilion. the National Inorganice assumed weight of the consumer and the studies were slimmarized to provide and Radionuclides survey is currently asnumed amount of drinking water insight to ambient air levels in urban underway and it is anticipated that data consumed per day. The "no effect level" and rurul locations. Data on the level of from this survey will he available for in mg/l has been termed the Adjueted inorganic chemicals in air were evaluation before promulgation of the AD1 (AADI). AADl's are calculated by: extracted from computerized RMCLe proposed herein. Determining the highest No- information developed by the EPA Dats on the occurrence of pesticides Obeerved-Adverse Effect Level Environmental bfonitoring and Support in drinking water comes from numerous (NOAEL). or the hwcnl-Observed- La bora lories. special studies conducted by the EPA Adverse Effect Level (LOAEL) in mg/kg Drinking water data come lrlrgely Office of Pesticides, U.S. Geological body weight/day: from either (1) National Interim Primary Survey and selected state agencies. Dividing by an appropriate safety or Drinking Water Reguhtions (NIPDWR) Published information on the occurrence uncertainty foctor (U.P.): compliance monitoring data, accessed of pesticides Is integrated into these Multiplying by the assumed weight through the Federal Reporting Data rummaries. Other sources of information of an adult (70 kg): and System (FRDS). or (2) special studies include various State surveys and Dividlng by the assumed amount of conducted by EPA's Ofnce of Drinking results of monitoring around hazardous water consumed by an adult per day (z Water (ODW). Six nrrtional surveys waste sites by the Superfund program. Iltere/day).

F4701 rev. 6-14-85 Federal Regisler / Vol. 50. No. 219 / WednPoday, November 13, 1985 / Proposed Rules - -- --.-- --_. -. 4e845 The formula for this culculation is as follows: some fluidclines outline!! ahovc for thi! NAS were applic:d. with the iidditioii of the applicution of an uncerteinty fii(:tlil of between 1 rind in whon rin AI11 Wits estimutcd from ri l,OtlEl. (if ir NOAEI. wiis unavailfible) in ordor to iidiusl thi! LOAEI. into thc riingc: of ii NOAH.. The guiddine : outlined Iiy the NAS (1977)and further modifit!il Iiy the I

F4701 rev. 8-14-85 46946 Federal Register / Vol. 50, No. 219 1 Wednesday, November 13, 1985 1 Proposed Rules

The application of the traditional human studies, were examined for each specified short-time period [usually one- uncertainty factor results in a chemical and a summary of the data la day, ten-days and longer-term [several concentretion of the chemid being less presented in the background Health months to several years)]. If data are thon that considered necessary for good Effects Criteria Documents. The available for all expoeure durations. all health. An intermediate uncertainty absorption rate assumed in the AADl three numbers are derived. For certain foctor was applied which did not result calculations was determined using a chemicals. there are inadequate data to in the allowoble exposure level being best estimate based upon the available derive a specific exposure level. For the below the nutritionally essential level. data. chemicals where there are inadequate The AADl was based upon a study 2. Calculation of the RMCLs data to derive a ten-day number, a ten- in which the inorgonlc chemical was day number is derived by dividing the Riven via food rather than drinking To determine the RMCL, the one-day number by 10. However, if this water. contribution from other sources of number is inconsistent with other levels Dulu suggest that certain chemicals exposure, including air and food should determined by using data of higher InResled via food may be absorbed less be taken into account. When sufficient quality, the divided number is not used. efficiently than via water. Thus, an data are available on the relative If there are inadequate data to derive a intermediate uncertainty factor was contribution of other sources, the RMCL longer-term number, a divided number ir Applied to account for the potential of is determined as follows: not used, and B longer-term number is higher ebsorption via drinking water. RMCL- (AADI)-(contribution from not derived. The longer-term number The endpoints used to derive the food)-(contribution from air). Thls must lederived from a subchronic study AADl are much more sensitive than the calculation assures that the total rather than an acute study; only acute troditional endpoints used in AADl exponure from drinking water, food and and short-term studies are used to caicula lions. air does not exceed the ADI. calculate the one-day and ten-day An intermediate uncertainty factor However comprehensive data are numbers. usually not available on exposures from wan applied which. according to The toxicological assessment methods scientific judgment. would provide an air and food. In these cases the RMCL is determined as follows: RMCL= (AADI) used to develop the assessments are the adequate margin of safety for the same as outlined for the RMCLe, Le., the particular chemical. (Percentage Drinking Water Contribution). identification of a NOAEL based upon TABLE2.-GUIOELINES ON THE USE OF The percentage drinking water human or animal data and dividing the UNCERTAINTY FACTORS contribution often used-in this proposal NOAEL by an appropriate uncertainly is a 20 percent contribution for organic factor(8). For RMCLe, a 70 kg adult chcmicals. For inorganic chemicals, the consuming 2 litera of water per day is actual contribution from other sources used in the calculations to adjust the AD1 for drinking water purposes. For 10 ...... Uncerlaq lyIa d IO wed r)(h VOW was often available and this data was SrPa)men(.l rewn1 on .P(.OPute 6. factored in the RMCL The NIPDWR these short-term assessments, the 70 kg rataol ewen hunum. adult consuming 2 liters of water per loo...... UnCaainIy IMU of loo wed rhsn used 20 percent as the-drinking water hvnan dab ue mt nailebb uld ex. exposure factor for pebticides. This day and the IUkg child consuming 1 liter bapolating from rahd resun. of long. of water per day are both used to ISm BMh an*rVI#. exposure factor is judgmental and is l.m...... uncsrtan* IyIU d 1.m uwd *.(m adjusted when mitigeting information calculate the numbers in terms of the human dab we nm NWL& and ax. exists. A wide range of environmental protected population. Both the adult and Irspc:attng ha rludm h anrruh ol the child are used in order to provide has man ~~FQNMJ. exposure distributions occurs across 1-10 ...... AdLMIOnaI l#wmmlyIyIU bshen 1 urban and rural populations and flexibility for those officials applying the and IO rhen urn0 I LOAEL lmterd number to use the value that is felt to d a NOAEL. differences exlst due to age and Intmnedmle ochr uncmmnty fmo, med. occupation. Use of a 20 percent best fit the needs of the specific --lV --lV lo rcrenm* ludommc *h.n b!lhd. situation. Both values are calculated to fbClU. contribution is considered to be I reasonably conservative and protective. present a broader perspecllve than The World Health Organization (WHO), would be available with one number. An intermediate uncertainty factor in "Guidelines for Drinklng Water The assessments are developed as was applied. since the traditional lo-fold Quality" (1984). assigned as little as 1 guidance values for short-term exposure uncertainly factor is applied in order to percent of the AD1 to drinking water situations, such as qpills or accidents, account for sensitive subpopulations where the chemical was known to and usually are issued separately by within the human population. bioaccumulate to a high degree, while EPA cs Health Advisories. They are not Another issue is the rate of absorption greater proportions were assigned assessments which are used to develop of chemicals through the gastrointestinal where the chemical bioaccumulated to a RMCLs or MCLe. The purpose of tract. Numerous factors affect the lesser degree. In "Drinking Water and providing the aasessments in this absorption of a chemical, including the Health" (1977), the National Academy of proposal is to elicit comment on these animal used, the presence of other Sciences provided projections of 1 scientific assessments which will be chemicals and bacteria, whether the percent and 20 percent as illustrations of then converted Into formal Health chemical was administered via food or drinking water cnntributions. Advisories. The following le a list of water and the previous dietary intake. Health Advisories which are available However, the absorption rates of 3. Short-term Assessments from the National Technical Information chemicals from the gastrointestinal tract In addition to the RMCLs, short-term Service at the address listed at the generally have been shown to be risk assessments (health advisories) beginning of the proposal. comparable in laboratory animals and have been developed for inorganic and humans. organic contamlnants for non- Health Advisories The absorption rate assumed for each carcinogenic endpoints of toxicity. Acrylamlde chemical in the proposal has been These evaluations are considered to be Alachlor determined on a case-by-case basis. The exposure levels which would not resul! Aldlcarb available data, Including animal and in adverse health effects over a roughly Amenlc

S-074999 OM6(02~12-NOV-85-15:14:38) F47M rev. 614-85 Federnl Register / Vol. 50, No. 219 / Wednesday, November 13, 1985 / Proposed Rules 46947 - Barium An issue that is considered in evaluate or reevaluate the chemicds Benzene assessing carcinogenicity is inhalation Cadmium carcinogenic risk to humane. An overall Carbofuren VI. ingeetion data. For all chemicals. the evaluation of carcinogenicity for Carbon tetrachloride total data basc ie examined. considering humane \tan mRdc on \he bneis of the Chlordane data on both ingeetion and inhaltition cowbined evidence from humans rind Chlorobenzene (Monochlorobentene) exposure. If (he data show the chemical experimental systems. The degrees of Chromium lo be carcinogenic through ingestion evidence for zarcinogmicity were Cyanide exposure. then the chemical will bs char~cteriredan follows: 2.4-D considered a poler.lial crrcinoger. and 1. P.. -easment of evidence for DBCP evaluated baaed upor the carsintipoicity from studies in humiins: Dichlorobenzenes 1o.m.p) carcinogenicity data. ($1) Ebfiicient evldunce. which 12-Dlchloroethane A second nituation coisints of inrl1r:atro that there is R causal 1,l-Dichloroethylene inetancee where the chemical hae been cis-1.2-Dlchloroethylene relationship bc:!wePn the ageni rind trans-1.2-Dlchloroethylene shown to be carcinogenic by inhalation human cemer. Dlchloromethane exposure but not by ingeetion exposure (b) Limited evidsnce. which indicates Dkhloropropane [e.d., negative data exiete on expoeure that a cuussl interp.-elation is cr9dil)le. p-Dioxane by the ingeetion route and there is an but that alternative iaxplenntion nuch 11s EDD (Ethylene Dlbromlde) adequate baais to loxicologicrllly chance, bias or confounding, could not Endrin dlstinguleh between the routes of be adequritely excluded. Epichlorohydrin exposure). In these instances the (c! Inailequate evidence which Ethylbenzene chemical will not be considered a Ethylene ~lycol indicateti that one of three conditionn potential carcinogen via drinking water prevailetl: (I) there were few pertinent Hepfachlor/Heptachlor epoxide and the RMCL will be based upon non- Hexachlorobenzene data (2) the available studis, while n-Hexane carcinogenic effectn. A third cnse ehowing evidence of assodetion. did not Lead consieta of chemicale which have been exclude chance, bins or confounding (3) Legionella demonstrated to have carcinogenic studies were available which did not Lindeno effects via inha!ation expoeure and the show evidence of Carcinogenicity. Mercury data are either not available or 2. Aeseesment of evidence for Methoxychlor equivocal via ingeetion exyo!iure. In carcinogenicity from studien in Methyl ethyl ketone these eltuations. the RMCL will be experimental animals: . . Nickel determined on a case-by-case basis by Nitre te/Nitrite (a) Sufficient evidcnce, which examining the applicability of the indicates that there is an increased Oxemyl inhalation data to drinking water incidence of malignant tumors (1) in Polychlorinated biphenyls exposure. Pentachlorophenol multiple epeciea or straine or (2) in Styrene 5. Evidence of Carcinogenicity multiple experiments (preferably with TCDD (Dioxin) Several groupe of ecientists have different routes of administration or Tetrachloroethylene using different dose levels or (3) to an Toluene attempted lo claasict chemicals on the Toxaphene basis of available e\ idence for urusual degree with regard to incidence, 2.4.5-TP carcinogenicity. The *e include the IARC. Bite or type of tumor, or age at onset. 1.1.1-Trichloroethane the NAS Safe Drinkin8 Water (b) 1,imited evidence, which means Trichloroethylene Committee and EPA via its recr-ttly that the date suggest a carciirogenic Vinyl chloride proposed riek assesement guidelines for effect but are limited because (I) the Xylenes carcinogenlclty (4Q FR 462941. etudies involve e single species. strein 4. Carcinogens The IARC is reeponsible for a program or experiment or (2) the experiments are on the Evaluation of Cercinogenic Riel= rost~ctedby inadequRte dosage levele. Evaluations of the toxicology of of Chemicals to Humane, which involves inadequate duration ol exposure to the substancea which may poesess the preparation and publication of agent. inedequate period of follow-up, carcinogenic potential ie a two-phaec monographs providing e qualitative poor survival, too few animals. or process. In the firnt phase, the aesessment of the Carcinogenic potential inadequate reporting or (3) the toxicological data base for non- of Individual chemical8 and complex . neoplacme produced often occur carcinogenic endpoints of toxicity waw mixtures. The assessmente are made by spontaneously and. in the past. hHve evaluated in the same manner as independent, Internationel working been difficult to claesify an malignant by describpd above for "non-carcinogene" groupe of experts in cancer research. histological criteria alone (e.g., lung end and AADIe are determined. In the The program hae existed eince 1R71 and liver tumore in mice). second phose, assessment made of the has evaluated over 585 chemicals to (c) Inadequate evidence, which evidence of the carcinogenic potential date. lndlcates that because of major (e.&, long-term bioaseeys in roderite and Criteria used hrevaluating qualitative or quantitative limitations. human epidemiology) a8 welt an carzinogen!c risk to humane were first the studies cannot be interpreted as Information which provldee indirect eetabliehed in 1971 and were used by showing either the presence or absence evidence (e.g., mutagenicity and othe: the L4RC for the preparation of the first of a carcinogenic effect; or thilt within ehort-term test ree\ille). The objectives 16 volume8 of the monographs. These the limits of the teets used. tlic chemical of thle assessment are (1) to determine criteria coneieted of the terme "sufficient is not carcinogenic. the level or strength of evidence that the evidence" and limited evidence" of Id) No date. which Indicatca that data eubatmce ie an animal or human carcinogenlcity, referring to the amount were not avallable lo tho Working carcinogen, and (2) to provide an upper of evldence available and not to the Crcriip. bound estimate of the poseible risks of potenc of the carcinogenic effoct. The ccllegorler sufficlent evldence a'nd human exposure to the substances In The rater monograph8 and IARC Ilni. id evldence refer only to the strenRth of drlnking water. Supplement 4, wed revised criteria to the experimental evidnnce that thcse

S-074900 OW7(02XtZ-NOV-8S-t3:t4:40) F4701 rev. 614-85 46948 Federal Regieter 1 Vol. 50, No. 219 1 Wedneeday, November 13, 1885 / Proposed Rdee chcmlcels arc carclnagcnlc and not to the In eome cases. the Working Group potency of the specific carrinogen. such extent of thelr carclnogenlc ectlvlty nor lo the considered that the known chemlcal a risk could be vanishingly emdl at very mcchenlsrn Involved. properties of a compound and the low doses. The House Report which 3. Assesament of data from short-term results from short term testa allowed its accompanied the Safe Drinking Water teats: tranefer from Group 3 to 28 or from Act of 1974, suggested that RMCLa for (H) Sufficient evidence, when there Group 2B to 2A. non-threshold toxicants (i.e., were at least three positive results in at Gmup 3-The chemical, group of carcinogens) should be zcra. leent two of three test nystems chemicals. induetriel process or RMCLS could be set at the anolytical maosuring DNA damage. mutagenicity occupational exposure cannot be deteclion Ilmit. Since RMCLs at zero or chromosomal effects. When two of claseified as to its carcinogencity to theo:etlcally are i~nattuinable.baaine the positive results were for the same humane. the levels upon defined state-of-the-art genetic effects, they had to be derived The EPA has proposed guidelines for analytical detection limits would from systems of different biological carcinogen risk assessment (49 FR provide measurable goah for complcxi ty. 462V41 which contaln a classification carcinogens in drtnklng water. The (b) Limited evidence. when there were systom lor chemicals usivg the degree of analytical detection hitIs. for all at lcast two positive reaulte, either for evidence of carcinogenicity. The practical purpuses. the functional different endpoints or In systems categorization scheme pliices chemicals equlvalent of zero and thus would representing two levels of biological into five groups: present the same philosophy as a zero complexity. Croup A: Human carcinogen (sufficient RMCL (c) Inadequate evidence, when there evidence from epidemiological RMCLs could be eel based upon a were generally negatlve or only one studies) calculated negligible contribution to positive ter ! result. Up to two positive Croup B: Probable humaii carcinogen lifetime risk using mathematical models test results were considered inadequate Group B1: At least limited ev.dence of which would estimate the number of if they were accompanied by two or carcinogenicit to humane excess cancer cases occurring in a more negative test results. Group B2: Usualry a combination of population as the result of a chemical of The IARC then placed the chemicals sufficient evidenct. in animals and epecl1,ed concentration being present in in one of three groups to reflect inadequate data in humane the drinking water. EPA would eelect m carcinogenic ri8k to humane. These Croup C: Poseible human carcinogen excess cancer risk level low enough to groups are quite broad and are not (limited evidence of carcinogenicily be considered a "virtually safe" level. defined by strict rules concerning the in aninlala in the absence of human Such a level is not really very different assesement of evidence from the criteria data) from zero and could be argued to fit the outlined above. The IARC placed the Group D: Not classified (inadequate requirement that the RMCL be set at the chemicals in the categories based on animal evidence of carcinogenicity) no-effect level with an adequate margin evalutltion of the criteria along with Croup E: No evidence of carcinogenicity of safety. eclentific judgment on other properties for humans (no evidence of EPA has evaluated these three of the compound which would affect Its carcinogenicity in at leost two approaches and baeed upon our potential carcinogenic risk to humane. adequate animal tests in different analysis and the public comments These groups ure defined as follows: species or in boh epidemiological received on the Phase I proposal, a Group f-The chemical, group of and animal etudies) three-category approach based upon chemicals. industrial process or The NAS (Drinking Water and strength of evidence of carcinogenicity occupational exposure is carcinogenic to Health. 1977. Vol. I) classified chemicale will Lr: used to set the RMCL. This humane. This category was uned only in fwrcategoric: based upon the approach is summarized in Table 3. when there was sufficient evidence from strength of the experimental evidence. Category I includes those chemicals cpidemiolo~icalstudies to support a These categories are: human which have sufficient human or animill causal association between the carcinogens. suepected human evidence of carcinogenicity to warrant exposure and cancer. carcinogens, animal carcinogens and their regulation as probable human Group 2-The chemicol, group of suspected animal carclnogens. carclnogenr. Thr RMCb for Category I chemicols. lnduatrial procees or In the Phalre I RMCL proposal, EPA chemicals will be proposed at zero, occupntional exposure is probably conddered three main options for Cotegory I1 includes those substances carcinogenic lo humans. 'hie category retting RMCLs for carcinogens. These for which some limited inconclusive includes exposures for which, at one options were: (1) Set the RMCLs at zero, evidence of carcinogenlcity exists from extreme. the evidence for human (2)sot the RMCLs at the analytical animal data. These will not be regulated carcinogenicity is almost "sufficient" ae detection limit, and (3) set the RMCb at as human carcinogens. However, well AS exposures for whlch, at the other a non-zero level based upon a RMCLS will reflsct the fact that some extreme. It is inadequate. To reflect thls claculated negligible contribution to possible evidence of carcinogenicity in range, the category was divided into lifetime risk. In addition. EPA requested animals exists. Thus. they will be hiRher (Croup A) and lower (Group 8) comment on the strength of evidence of treated more conservatively than degrees of evidence. Usually. cntegory carcinogenicily and how thls could be Category 111 substances. Cntegory 111 2A WAS reserved for exposures for factored Intq the RMCL determinations. Includes substances with Inadequate or which there was at least limited RMCLs could be proposed at zero, no evidence of carcinogenlcity. RMCLs evidence for carcinogenlclty to humans. based upon the inability of scientists to will be calculated based upon AADls. The data from studies in experimental demonetrate experimentally a threshold anlmals played an Important role in of effects for "carcinogens". Thls leads Table 3 assigning studiee to category 2. and to the assumption that since no Three-htegoy Approach for Setting RMCh particularly those in Group 8. thus, the threshold dose can be demonstrated for Category I-Strong evldance of combination of suifficient evidence In carcinogens, any exposure theoretlcally csrclnogenlclty. animals and Inadequate data In humans would represent some finite level of risk EPA Group A or Group B usually resulted in a clesslficatlon of ZB, lor cerclnogans. Dopendlna upon the IARC Croup 1,Uor ?B

F47m rev. 0-14-65 Federal Register / Vol. 50, No. 219 1 Wedneeday, November 13, 1985 I Propoaed Rule8 48940 - Category ii-Eyulvocal evidence of wdghl of evidence approach in the Pentachlorophenol, cis-l,2- crrclnogenlclty. proposed EPA carcinogen risk dichloroethylene, truns-1.2- EPA Croup C lhRCCroup3 assessment guidelines takes into dlchloroethylene, o-dichlorohmzene. m- Category Ill-inadequate or no evldcnce of account the total evidence regardless of dichlorobenzene. 2.4-D. 2.4,5-TP. cnrclnogenlclty In anlmsis. exposuro route (includes inhalation and ethylbenzene. methoxychlor. toluene. EPA Group t! or E ingestion exposure). By this approach, xylene. atrazine. and simuzine hHve lARCCroup3 asbestos, arsenic and chromium are in been cluasified in EPA's proposed Group The method for determining the Croup A (sufficient evidence in 0 inadequate unlmril evidence of RMCLa for Category I1 chemicals is humans), nickel and cadmium are in carcinogenicity. more complex than for the other Croup 81 (limited evidence in humans), Endrin and cerhofurlln hnve besn categories. To be placed in Category 11. lead Is in Croup 82 (clrfflclent evidence classified in EPA's proposed Group k chemicals are not considered to be in animals), and barium, nitrate/nitrite. no evidence of curcinogmicity for probable carcinogens via hgcetion sodium, cyanide. copper. mercury. humens. selenium. silver. molybdenum. and although some data is available that Table 4 presente a cluesilication of IIW causes concern. these substances su;fales are in Group D (inadequate Thus, evidence). SOCs and inorqanicn into the three should be treated more conservatively The carcinogenicity data for the category opproach for eetling RMC1.s. than Category 111 "non-carcinogens," yet inorganic chemicals indicate that the As noted in the table. there ere six leas conservatively then Category I carcinogenic potential from ingestion chemicals which are cieanified in chemicals. Two options are available for should be distinguished from that by Category Ii (limited evidence of setting the RMCLa for Category I1 other routes. Areenic, In humuns. has caicinogeniclty): styrene, 1.2- chemicals: the first option involves sufficient evidence for carcinogenicity dichioropropane, monochlorobcnzene. basing the RMCL upon the AADI which by inhalation and by the oral route. lindane. asbestos and arsenic. Tubic 4h le based upon non-carcinogenic however other factors such as the presents the rationale for the placemml endpoints of toxicity using an polcntial that it is an essentiul element of each chcmical in its rcepactive uncertainty factor according to the were also considered in developing the category. Table 5 preeents the RMCI. adequacy of the data and loxicological proposed RMCL. Although lead le options for the Category II principles. To account for the possible technically listed in Group 82. the test contaminants. See Section VI11 for a evidence of carcinogenicity, an dosages that induced cancer in animals further discussion of the RMCLa for the additionul filctor would be applied (e.g., were beyond the lethal dose in huniane individual chemicals. Comment is AADI divided by a factor of 10 or some and thus the RMCL for lead will be requested on the three-cutegory other value). A value of 10 is commonly bilsed upon other sensitive endpoints. approach for settin8 RMCLs and on the applied for the contaminants proposed Asbestos is a proven carcinogen by proposcd ciussifica tione of chemicals in for rcRululion todny. Tradltionally, for inhalation, but the evidencp with orrii each cntegory. every additional factor contributlng to exposure is limited even after extensive uncertainly, a factor of 10 hen been studies have heen performed. The TABLE PRELIMINARY CLASSIFICATION OF included. Equivocal evidence of evidence for the carcinogenicity of SOcS AN0 lNOROANlCS INTO THREE CAIE- carcinogenicity is such an additional chromium, cadmium, and nickel is WRV APPROACH uncertainty factor. However, a factor inadequate by the oral route but other than 10 will be applied if the p'm sufficient by the inhalation route. Chemc.1 properties of the chemical dictate an I ' , :I ' 111 ' In this proposal. the RMCLa for those ---...... -...... alternate factor. The second option chemicals in Croup D are set based involves basing the RMCLs upon B DBCP a upon chronic toxicity data (Rc~ulatory ChOlWl a lifetime risk calculation in the range of Croup Ill). In addition, the RMCLs for fmnkuotwnn a. to 1O"using a conservative chromium. cadmium, arsenic and lead MOauMg- a Alunku 9 X method. This risk range is commonly are also being set based upon chronic 10.~ a considered to be protective and in the toxicity data. for the reasons outlined AcWmd. .. .a future, if additional data led to above. The RMCL for asbertos is set Em .. .. a reconelderation of a chemical's OIWM.' . . a based upon an excess risk level H.oumra*...... !I I carcinogenicity. the RMCL would still be (Regulatory Category 11) due to the weak PCB...... 'a ' set at a H.otschbr.oondi ... jK level that would represent an oral carclnogeniclty dab. An RMCL is Llldm...... I extremely low nominal risk. EPA will not proposed for nickel due to problems shr- a use both approaches to set the RMCLs with the limited toxicolopical data bese. I.?.l+*bopW8M /. ,a umomrpobrvm , . ... :a for Category I1 chemicals. The nrst which is now being expanded by new p-UhbW#Vd ... I option. basing the RMCL upon the studies. A*rb ...... ' .; L AADI, will be used if sufficient valid cm.t.?.oslb~, . . I SOCs *um.I,Z.~~ a chronic toxicity data are available. If o.achla&alrmm . I' I. a sufficient data are not available, the DBCP. dioxin, epichlorohydrin, mOc- . 4 : I 2.40 ... I a RMCL will be based upon a rlsk hexachlorobenzene, alaphlor, €em ...... a calculation. toxaphene. acrylamide.,EDB. chlordane. Emrcbrurr...... j . ,I MmS.*cho, ...... The following is 8 summary of the heptachlor, heptachlor dpoxide and n ...... ; . I .. I PCBs have been cl~ssifiedin EPA's ld- classification of the SOCs and lOCs 2.4.5.1P...... I...,. a based upon the classific~ti~nsystem propospd Croup B2: sufficien! evidence Xh...... i .....1 I Ab'u~m. , . ., , . , . . , 'I outlined in EPAs proposed guidelines of carcino eniclty in animals...... I . ,I.' Id for carcinogen risk assessment. 12-Dichf oropropane. styrene. Mohrm- ...... 1 ... I.. . a monochlorobenzene, and lindane have *I-mP==hooc-rrd, 1 nb.*a ' "' ' I IOCs been classifled in EPA's proposed Croup 1 The classincation of the inoganic C limited evidence of carclnogeniclty in I chemicals for carclnogenlclly by the animals. 1-

F47M rev. 6-14-85 48050 Federal Register / Vol. SO, No. 219 / Wednesday. November 13, 1985 / Proposed Rules -

TABLE 4A.-cUSSlFICATlON OF SOcS AND IOCS BASED ON PROPOSED EPA GUIDELINES ...... -...... -- ...... rhm2.i TEPA~~-_-- Bow __- - .... A. SOCI ..., ...... -...... , ...... M)CP ...... E2 ...... cUanog.n* n rotslniu Cra*mn ol luwtwch n rots md mcd 04 bom mw,pnmm n Mwl UIIS 2.3.7.8.TCW ...... BZ ...... Crcmgmc n fohlrmU n kr,.~od. 1- .(e 1-10 mdrsr n hyrvrn Ew..MrxOham ...... RZ ...... Cr- n rata. c.nCrr n l0rwt-h ([email protected]&cut- qat- Ltw. wrd nos.( hrbrutn Wubtmn) uu\.qn No hnrr 1: 1: E2 , Mc~nchluctanzem ...... I_.Crc- n fa~slhmtuslmcrLNC coma No humen vndavr AtlCMg ...... : i 82 ...... c.,onog.nc ratrim. mw lo.agMna...... BZ ...... Do Ac*lrm& .. 1 82 ...... Cuupg.nc n hm .ploar. a1 mdbple ulw Em .. 1 BZ...... c~cn0g.n~ n ia~sirm~ by 0.v.o.. h~atlon n mc. Chludnne ...... ,,iBZ , ,...... Cvcnopacnbomwxwofmu L"hepo10C.hllut~ nmxw 82 ...... Urcmogmc n mCr Llvu h.p.tocelMr cy- Hcg(~Mg€ponds , . 82...... , . Cucnogenc n mu and fala. H.gl(o@Mu c~cmnU PCR ...... E2 ...... t.rCm KO's cu- n mu ud fats tual) Ro&ma twwp and mahgnmt nC0I.m Lm~iorn ...... C...... Mrgrul lumsd hk.r d born u..) n mu. Cwuropmc metotdm I2 rkhloropopone . C ...... Lmed snd.no d af~flrIn m E- n fall oouvocal (bud on NTP boll f.DOrcl SWm. .. C ., ., .. , ...... Cucwmpnlc n 1.1s Ah.QIrltwoncWu .d.mnus and wclnQrU~n born w#w ol 1.1s (uot) Ccarrra. (hw MwMS Ce nol cm*M. Momhluctanzna .. C...... Increawd ocwfonce a! neoplntn no&h d hkr n h@ dow mob fats 18~..don NTP bafl f.Pal1 Puolu.hbfophenol .... D ...... Neg.tlva n swlm n rits and mcd. m~.bru no( really .dd.wbn lo, No hunm md.ncr cn and lram-t.z&h(oc. 0 ...... NdIWl~ Wthvbnn 0-hhluobanfa...... , .... D ...... Negnli rMah born rala and mice NTP (dafl fopon) 0.v.p. sluda Some UMn bhod bo uud Ync. hgh dow w hM ben bdorr MTD. m.hhlorobmzsna...... 0 ...... ,...... Ilot ieated. 2.4.0 ...... D...... Inodsqunt. rwrul drtr lo Cl.S* fU cy- 2.4.5.TP. .... , ..... D...... Do Ethlcba?em ...... 0...... Nd Issled Mcthor).tw ...... 0...... InOdeqMte aninul svidence IKooc~1ew)lS Toluone ...... 0 ...... Wlhmh om CllT bioosuy (mholatm)up Io XI0 m MTD wn no( feochsd MegUnm n ma0b.l bony XTierm ...... , , ...... 0...... ImUnicia( Mumoton lo blamna rrhsma u no( qlem nrsn is WCmoQonlC Alfazm ...... 0...... Inadequate drln lo claaMy Sannre...... D ...... Do. Endrin...... E ...... Nsgalive rew)la in s-. kslwhg NCI. 1078. Waul. Carboluan ...... E ...... Nsgali h 2 lpecar and nogatwe m shi.lam leais AWarb ...... E ...... Megalwe rerJIs m wmal a- irsb&g me NCI bionuy ...... I ...... E. loca ...... Asbator ...... A ...... By cnhrlatmn. cacnogenc n humom and annnols By whm ol ntamedate (iIO pm length1 range chwofde nkn(a.kmed Hdme h ~~lS~bargnPorvp #I Mb rata, HWrWQI. N0d.W apdaolo9cl-l UO-10 lo Mclud. Ih. Chanc.l a cucmoganc vh ngertii Af.ofi~...... A...... Qwcinogem in humem by Walmand ngertmn. Ho*aa.hs cbwncal hnp0tenh.l oswcMI nuhsm vahm chann...... A (besed on brla Cuc*logaic in huMm by *rhbun nnd roods by nbabochaol mldlotmn Mowwa. iw.mo n "0" methe10 a mdaquole andsncs IU a'.) lo conch& (h.1 me ctbmcal a ~chcgmcvi. ngsrtDn . cadmn...... El...... Lmited evidsoce n humern expored lo ce6mm hmer. unccw In 1a11 emud lo mdmun cNad. ouowl. mpctmn nle (vngn n 01unok i pen cdmhm una Horsva. rwalmg n "D" mco ma0 m wudqmto eadera lo conclude Rut (he cham& a cycnooa wu I Vh0n. Nshd ...... 1 Bt (baled Q) Lmcted sndence in tumam by n(ylal~n.Wnuent sndara in -b hhakhon md nphon Homa.rmtq W "D' .nC. me rrrbsulfde and *ub.gurte sndara IO cmMe mol Hm chemul a a ur- yu ngarm urbonyll Leed ...... 82...... sUnuen( svidence in armrh. Kdmy hmas br ual rdon rats wo*ara. mUmaem bur lo r+ole n humon Uavgen vu -ha, Barn ...... D ...... InsdeOuta Ma lo clascdy. NmttelNltn(s ...... I0 ...... Do sodnrn...... 0 Do clam...... , .,ID ... ::::::. :... .::; .. Do axlPm ...... ID ...... Do. sdwlnml ...... jD ...... Do *m...... D ...... Do. MotWenwn. ..., jD ...... Do. Sul!alm...... , ....i D...... Do Macwy ...... D ...... Do ~-- .._1.-

TABLE5.-RMCL WTIONS FOR CATEGORY 11 TABLE5.--RMCL OPTIONS FmCATEOORV I1 CONTAM1NANTS~fltiflUed ~TAMINANTS-Conliflued

F4701 rev. 6-14-85 Federal Reglsler / Vol. 50, No. 219 / Wednesday. November 13, 1985 / Proposed Rules 46951 - - - VI. Mlcroblological RMCLs Varlrinces could be issued for systems necessarily the actual numtierl of that can demonstrate that the raw water disease outbreuks and cams hiis The Interim I'rimary Drinking Water quality is such that installation of these Increased. Rcgulations. along with the predecessor technologies would not be needed to U.S. Public llealth Service standards, protect public health or that alternulive TABLE7. -1NTE AIM REGULATIONS: have led to widrly improved drinking tcchnologies are at least cqually MICROORGANISMS water quality over the last several __ ~ _-__. ._ . . effective. Summaries of the outbreaks of Pnrlnnlel ' MCL decades. Compliance with the diseasc. availability of analytical + -_... -. . regulations for total coliform and methods. und human health concerns turbidity is being nchieved by most arc provided below. public water syrtems. No longer do widespread epidemics of typhoid fever TABLEe.-PROPOSED RMCL8 FOR and other waterborne disemes occur in MICROBIOLO&%LPARAMETERS the US.population. Yet. waterborne -___-.--_ disease outbreaks are at significnnt Pm.mta ' levclr and the trend in the reported ~ -__--.- -+ ""e number of outbreaks is increasing. TOW thwsma ...... zwo Recognition of watert)orne illness is .. .. 0 I N1U 8 difficult nnd studies indicritc that a Gurd.I-? ""...... ; Zm> relatively small percentage of ricturil Vlvm' .. , .. : zao cases in being reported. Some of the outbreaks are cnused by fecal agcnts such as Salmonclla and Shixnlla whose presence should be indicntcd by uccompanying coliforms bacteria. total A. Interim Rcgulationa urd Recent Many outbreaks are caused by agents Oufbrcoka WaferhorncDi.qcosc such as Giardia nnd viruses for which of total coliform bacteria are inadcqunte as The Interim Regulations rely on the an indicator. Thus. cven though total measurement of total coliforms and coliform nnd turbidity regulations are turbidity as indicators of water being met by most systems and the treatment efficiency, deteriorfition of From 1971-1980,.W percent of the microbiologicnl safety of drinking wntcr water quality in the distribution system. outbreuks reported were in non- hns improved greatly over the years. and fecal pollution. Applicable to both community wutw systems. 39 percent in significant problems continue to nxist community and non-community community systems. and 11 percent in and additional regulatory controls ~ystcms.specific MCLs of the Interim private systems. Although most of thc appear necessary. Regulations lire shown in Tnble 7. outbreaks were from nun-community Because total coliforms and turbidity Monitoring requirements for coliforms systems, about 75 percent of the illness are satisfactory indicators for a number depend upon the size of system. and occurred from outbrenks in community of organisms which have adverse health range from 500 samples per month for systems. Between 1971-1980. the major effects(pathogens). RMC1.s will be systems serving more than 4.7 million causes of outbreaks in community water proposed for both. In addition. RMC1.s persons to one sample per month (or per systems were treatment deficiencies will also be proposed for Giardia and 3 months in some cases] for systems (49%) and contamination in the viruses l)ec~usethey have adverse serving 25 to IO00 persons. Turbidity distribution system (32%).Almost all health effects and their presence is not monitoring in required daily for systems outbreaks (83%)and illnesses (80%)in identified by conventional inJicators using surface water supplies. non-community systems wcrc a result of (c.R.. total coliforms). The proposed From 1971-1983, there were 427 using ground water without treatment or RMCLs appear in Table 8. As discussed reported outbreaks of wnterborne using ground water with inadequate later, an RMCL Is not being proposed at disease in the United States. involving treatment. primarily interrupted and this time for heterotrophic bacteria 1i.e.. over 108.oOO individuals. Forty inadequate disinfectiorl. standnrd or hetreotrophic plate count outbreaks and 21.000 cases occurred in Most known agents of wuterborne (tIPC)) because thcre are not yet 1983 alone. Many outbreaks. perhaps the disease cause acute gnstrointestinal sufficient drita to c,)rrelate toxicity with great majority. are not reported to the disorders. especially diarrhea and HPC and because they are likely to be Centers fcr Disease Control (CDC), cramps. During the period 1971-1983. the controlled through the mechanismr for which keeps records on the incidence of most commonly identified prithogen wns controlling total coliforms and turbidity. reportable diseases. This is because the protozoan Giardia lamhlia. During In addition. an RMCL ie not being only a few types of waterborne diseases these years. there were 77 reported proposed for legionellae because the are required to be reported and also outbreaks of waterborne giardiasis role of public water supplies in the because disease outbreaks age often not involving nearly 23.000 cases. A number etiology of the disease has not been recognized in a community or. if of bacteria also have recently been determined. and because control of recognized. are not traced to the implicated in waterborne discrisc. Thesc legionellae is more effective at locations drinking water source. In Colorado. an include Salmonella species. Shigella of susceptlble populations. EPA-funded effort to improve the species. Campylobacter icjuni, Ycrsiniu In addition. EPA is considering outbreak reporting system indicated that enterocolitica. and enteropathogenic E. proposing a treatment technique only about one-quarter of the actual coli. Viral agents implicated in recent regulation which would require: I11 outbreaks were being recognized and waterbnrne illnesses include Norwalk Sirface water systems to practice. reported. As recognilion ofwaterbome and Norwalk-like agents. rotaviruses. filtration and disinfection and (2) ground illness has im roved, the trend In the and the hepatitis A agent. In about half water systems to use disinfection. reported nurn!er (although not the waterborne outbreeke the causative

S-071999 (105 t(O3 M I2-NOV - 85 - I 5:2O:J4) F4701 rev. 6-14-85 46952 Federal Register / Vol. 50, No. 219 / Wednesday, November 13, 1985 / Proposed Rules

agent has not been found. There le Association with fecal contamination, I Presence-Absence concept as the basis growing suepicion that many of these (2) die-off times in water, and (3) of the total coliform MCL. may be due to viruses. Unfortunately, resistance to disinfection or other the unavailability of suitable analytical treatment. Although the total coliform C. Turbidity techniques have impaired efforts to Indicator le an inexact tool, fecal resolve this issue. Turbidity in water is a non-specific pathogens in ambient water are usually measure of suspended material in D. Toto1 Coliform Boclerio accompan:ed by substantially higher drinking water and is meosured by levels of total coliforms. Since higher determining the degree of light Total coliform bacteria have been levels of pathogens should roughly used for decades tis the primary scattering catxed by particulates in a translate !o greater risk of disease, menaurement of the microbiolugical sample. 'I'llrbidity has been used for coliform densities indirectly scrve as a decades as an indicator of drinking quality of drinking water. Total coliform measure of the risk of waterborne bttcteria nre a measure of the efficiency water qlrality indicating the presence of of water treatment. diacloae disease. Treatment which provides such particulates as clay, silt, finely deterloretion in the distribution system coliform-free water as measured by the divided organic and inorganic matter. and signal the possible presence of fecal standard tects shruld reduce pathogens and microorganisms. Analytical con tom inti t ion. Ana I yt ica I me t hodology to minimal levels, even though large methodology for iurbidity monitoring is for total coliform monitoring has existed volume risk-free water is probably available. Currently, the only EPA- for decades. Current EPA drinking water una t taintl ble. approved tcchnique is the rqulntionn specify the use of nither the Despite these and other limitations. Nephelometric Method. This is also multiple-tube fermentation technique or total coliforms are still the single most recognized as an acceptable technique the membrane filter technique. Both useful indicator of drinking water by Standord Methods for the enjoy widespread acceptance and arc quality. Because total coliforms most Exomination of Woter ond Wastewater. directly measure pathogens which recognized as suitable methods by Turbidity is an imprecise measure Stondord Method8 /or the Exominotion widely occur in drinking wster, EPA la proposing an RMCL for total coliforms. because particulate characteristics vary of Wolcr ond Wastcwoter. EPA is elso from system to system and seanonally considering additional analytical [Toassure a safe drinking water supply, control of total coliforms should be used within the same system, and some methods, nuch as Clark's Presence- particulate types are more significant Absence lest (see Standard Methods. in combination with other microbiological parameters and than others for human health. The more 6th ed.) which detectb coliforms but Importent particulates appear to be does not quantify them. protective measures, e.g., turbidity, filtration and disinfection.) The larger than 0.03 pm in diameter and are Coliforms are usually present in usually organic materiels. Turbidity is of fecally-polluted water and are often discontinuance of total coliforms as an indicator of treatment efficiency would concern in drinking water becaune of the aaeocinted with dieeane outbreaks. following characteristics: Although coliforms are not usually eubetantially undermine the ability to pathogenic themselves, their presence in predict the potential presence of Turbidity can reduce the efficiency drinking water indicates the likely pathogens, even if turbidity monitoring of disinfection. presence of pathogens (e.g., Solmonello le retained. Turbidity removals, for -Certain particles protect adsorbed and Shigello). However, use of total example, cannot measure disinfection pathogenic organisms against coliforms has a number of drewbacks effectiveness. disinfection. In geireral. inorganic including the following: The object of an RMCL for total particles such as clays and water Given their ubiquitous nature, coliforms is to recommend that as a goal flocculating agents appear to have coliforms are often found in the absence the consumer will not be exposed to a little, if any. protective effect. In of fecal contamination. eufficient dose of a pathogen to result in contrast, organic particulate matter, There are reports of pathogen disease. Since the relationship between whether cell debris, sewage solids. or occurrence and disease outbreaks where coliform and pathogen levels is highly living or dead organisms such as coliforms were not detected. variable, the prdposed RMCL for total nematodes or crustaceans, can Coliforms are inadequate for Coliforms should be zero. i.e., no provide marked protection to predicting the presence of pathogens/ detectable coliforms/100 ml as microorganisms associated with them. toxins not associated with fecal measured by the Most Probable Number -A significant disinfectant demand can contamination such as atypical (MPN), Membrane Filter (MF), and other mycobacteria, Legionello. and algal chemically interfere with disinfection EPA approved analytical methods in during treatment or maintenance of a toxins. order to assure maximum protection They also may not adequately disinfectant residual in the within the limits of the measurement distribution system. predict the presence of enteric viruses, technique. This RMCL includes an Giordio and some other organisma, adequate margin of safety. While the The turbidity can be caused by because they are less resistant to RMCL is being proposed at zero, the particles that are toxic themselves or treatment (e+. disinfection) than these concept of "presence-absence" is being that adsorb toxic inorganic or organic organisms. considered as the basts for the substances from the water. The qualitative use of total coliforms enforceable MCLs. This would involve Higher turbidity levels can also can be scientifically justified. but there measurement of total coliforms to Interfere with total coliform analyses by la an absence of scientific data in the determine only if coliforms were present the membrane filtration procedure. literature supporting a particular value or absent without quantification. For Turbidity is a measure of the for coliform density. below which the example, MCL regulations could specify efficiency of drinking water coagulation water can be considered safe. Pathogens that 85 percent of samples examined and filtration processes. Removal of and outbreaks have been associated over a given time period have no turbidity usually provides concommitant with coliform densities ranging from coliforms present. Public comment is removal of microbial pathogens, zero to very high levels. This is nut requebted on setting an RMCL of zero especially those which aggregate on surprising: pathogens vary In thelr: (1) for total collfonns end on the use of the partlculetes, as well as partlculate

-4999 ~52(0~~12-NOV-ES-IJ:~16) Federal Register / Vol. 50, No. 219 / Wednesday, November 13, 1985 / Proposed Rules 48953 - - matter which in either toxic itself or record where r,utbreake were be overloaded and improperly operated. adeorbe toxic contaminants. accompanied by eudden risen of In all four situations. the systems were "hue, turbidity represente many turbidity in filtered coliform-free water. in compliance with total coliform and concerne in drinking water quality but In addition, turbidity in monitored at turbidity MCLe. distinct relationehipa between levels of leaet daily and resulte are available in a The populatione most HI risk are those turbidity and the safety of the drinking much ehorter time than for coliforme. coneuming ;dace walere which are water are not quantifiable. tlowever, as Other organizations eupport turbidity either untreated or only chlorinated. a etandard eanitation principle, the controle including the American Water Giardia are effectively controlled bv lower the turbidity of treated water. the Works Aesociation (AWWA] and the filtration (including coagulation) and less likely the water will contain World Health Organization (WHO). dieinfection. Dieinfection alone is not contaminants deleterious to human The AWWA policy is a8 follows. normally eufficient. It in estimated that health. For this reason and because Today's consumer expects a sparkling. over 85 million people are served hy turbidity in commcn in drinking water clear water. The goal of lens than 0.1 unit of surface water eyetems that either eources, EPA ia proposing an RMCL for turbidity insures satisfaction in thin respect. provide only disinfection or no turbidity. There is evidence that freedom from disease treatment at all. As organisms in ansocioted with freedom from with the total coliform RMCL the turbidity. and that complete freedom from Cyst recovery and analysis object of the turbidity RMCL in to tante and odor requires no lens than such procedures have been publiehed in the provide maximum aeeurance that the clarity. improved technology in the modern literature, but they are coneidered coneumer will not be expoeed to a treatment processes make this a complctely insensitive. tedious and expensive. The eufficient pathogen done to renult in practical goal. most commonly used method for dieeaee (including a margin of eafety). The WHO guidelinen for turbidity recover1 and detection of Giardia from On thin basin. the propoeed health goal state that "turbidity muet always be water wan developed by EPA. This for turbidity in 0.1 N1 J. This in primarily iow. preferrably below 1 NTU and involves filtering large volumea (up to baaed upon the premise that the lower alwaye less than 5 NTU." 2.000 lilere) of water through an Orlon the turbidity levele, the leee the Public commente are requeeted on fiber filter. separating the cysts, from the probability that aggregated netting an RMCL for turbidity in drinking fiber, and examining the cyst microorganisms are entering finished water. Specifically: concentrate microscopically. This drinking water. Significantly, there le a level of 0.1 NTU appropriate for procedure appears in Standard Methods appears lo be eome correlation between the RMCL? If not, what other level and for fheExominafion of Water and turbidity removal and Giardia removal upon what baeie? ._. - Wastewater (1Sth.ed.). as a tentative- . . efficienciee in filtered water. Setting the method. Beyond the difficulties in RMCL at 0.1 NTU represents the loweet D. Giardia recovery and detection. it is not yet level for which eufficient data ale The protozoan Giardia lamblia causes possible to distinguish beiween viable available land is essentially the more waterborne dieeaee outbreaks in and non-viable cyste. Thin method is analytical level of detection). Lower the United Statee than any other single therefore not coneidered available for turbidity can be measured, but only identified etiologic agent. Symptoms of the monitoring of waterborne Giardia. through careful meanurements under giardiaeis Include diarrhea. fatigue. Promising reeearch is being conducted controlled conditions. An RMCL for ahdominal cramps, and possibly other on Giardia recovery and analysis turbidity of zero would not be gantrointestinal symptoms. and theee techniques. appropriate eince even distilled water may pernist for several days to several The proposed RMCL is based upon L* hen turbidity of aboulO.05 NTU. In months. For these reaeons. EPA is human study. In this investigation. male addition. additional benefits of proposing an RMCL for Giardia. volunteers were fed human-source achieving very low turbidiliee include Between 1971-1983. there were 77 Giardia cysts contained in gelatin the following: repcrted outbreaks of waterborne capsules. Those receiving one cyst were Several studies have demonelrated giardiaeie with nearly 23.ooO canes. The not infected. while infections did occur very subelantiel removal of Giardia trend in outbreaks has been on the in the group receiving ten cysts. A major cyste by coagulation and rapid granular increaee. probably due to greater deficiency of this study is that cyst media filtration. However, thin would recognition and reporting of giardiasis viability was not established: thus it is not suggest that a drinking water with a outbreaks in recent years. Waterborne possible that a sizable fraction of the low turbidity level would de facto be giardiaeie repreeented 15.7 percent of ingested cysts were non viable. In eafe from Giardia. Giardia can be the total reported cases of giardiasis in addition. only two individuals were present in low turbidity unfiltered 1980 and 2.4 percent in 1981. These tested at the ten cyst level (both. walere. percentagee. however. may substantially however. were infected]. Recent Removal of turbidity particles for under-repreeent the actual ei!uation. unpublished data with mice support the cyet removal will aleo eubetantii~liy eince the route of transmieeion for many low infective dove for Ciordiu. In four reduce levels of other pathogenic canes ia unknown and may in fact be experiments. the averaRe dose at whic;h organieme and toxic particulate matter. waterborne. In Penneylvania recently. 50 percent of the animals were infected euch as bacteria. pathogenic viruses and there were four separate out breaks of (I&) were 1.4. 2.6. 3.8 and 17.6 cysts. protozoan cyete. waterborne giardiasis. with about 700 Since some of these cysts miiy have The total coliform group. while the casee. Over 350.000 individuale were been non-viable. the ID,,, dose may eingle beet indicator of water quality, in being nerved by public water systems actually be lower than the rc!sults inadequate by iteelf to meaeure drinking under boil water orders (Le.. water indicate. water quality. The meaeurement of provided by a public water system in not On the basis of these studies and turbidity complemente coliform eafe to drink unleee boiled first). In three inclusion of a safety factor. the R,MCI. is monitoring since particlee may interfere outbreake. the systems provided only proposed at zero viable cysts. Because with coliform analyeia md particlee may chlorination. In the remaining outbreak. of the insensitivity of the currently chelate toxic materiale wen in the coagulation, filtration and dielnfection available analytical procedures. the absence of coliforme, There are cases on were uaed, but the system appeared to potential for intermittent contamination

I: F47M rev. 614-85 - 46954 Federal Register / Vol. 50. No. 219 / Wednesday, November 13, 1985 / Proposed Rules and thus difficulty in monitoring, and undoubtedly contributes to this under- monitoring. a treatment technique lack of technologically and reporling. requirement is being considered for economically feasible methods. The most important of the waterborne proposal in the next rulemaking. Thie treatment requirements are being pathogenic viruses are the Norwalk and could include codgulation. filtration and considered /insteed of setting an MCL). Norwalk-like agents, rotavirus, and the disinfection for water systems using However, the inability to measure these hepatitis A agent. Except for the latter. surface water and disinfectlon for contaminants alone doelc not prevent their predominant health effect is acute systems using ground water. establishment of an RMCL In this case gastroenteritis. Hepatitis A agent results Alternali.rely. an easily measurable it is reasonably clear that any Giordio in hepatitis. All have been implicated in surrogate for waterborne viral lamblio cyst can have an adverse health recent waterborne disease outbreaks. pathogens could be selezted as the effect. Therefore EPA is setting an While serological techniques are proper regulatory approach: however. RMCL of zero. Treatment techniques available for identifying these agents the only techniques currently under could include filtration and disinfection [e+. radioimuno-assay, immune study are classical enteroviruses and for all water systems using surface electron microscopy. and others). there coliphage and these are not considered water. Ground water le not nearly as are no satisfactory culture procedures sufficient to provide protection against vulnerable to cyst penetration since the currently available. Promising research the myriad of pathogens potentially aquifer and the overlying soil usually on culturing rotaviruses and hepatitis A present in various drinking waters. A serve as an effective barrier. Thus. agent Is presently being conducted. variance could be coneidered in those filtration of ground water will not be The classical enteroviruses circumstances where a system is able to proposed. Variances under section 1415 (poliovirus. echovirus. and demonstrate to the satisfaction of the may be considered in those COXSriCkieVirus) are common in ambient State, by an on-site sanitary survey and circumstances where the system is able water and are occasionally found in other means to be specified. that to demonstrate to thd State by a drinking water, but they have not been treatment would not be needed to sanitary survey or other means to be implicated in recent outbreaks. protect public health because of the specified. that the treatment is not Nevertheless. their health effects may be quality of the raw water supply. The needed to protect the h?alth of persons severe (e+, meningitis. paralysis. treatment technique requirements, if because of the quality of the raw water. myocarditis, diarrhea). any. will be proposed when the MCL for The treatment technique requirements Unlike many of the other agents, other contaminants are proposed. will be proposed when the MCL for recovery and analysis procedures for Criteria to be used by public water other contaminants are proposed. these enteroviruses do exist. some of systems and States in determining if a Criteria for determining if a variance which are described in Sfondord variance would be appropriate will be would be appropriate will be included in Mefhodsfor the Exominofionof Woler included in the proposal. the proposal. ond Wosfewafer(15th ed]. Viral assay, Public comments are requested on this Public comments are requested on this however, is beyond the capability of approach of setting an RMCL of zero for approach of setting an RMCL of zero for most watp' microbiology laboratories viruses and setting treatment Giardia and treatment requirements to and must be done by a trained virologist requirements for control of viruses in control Giordio in drinking water. working in specifically equipped viral drinking water. Comments are also Specific comments are also requested on laboratory facilities. requeeted on the following: the following: The minimum infective dose for some Are analytical methods available Are analytical methods available strains of waterborne vimses is very (i.e., is it economically and 1i.e.. is it economically and low. There is evidence that in some technologically feasible] to ascertain the rechnol~gicallyfeasible) to ascertain the instances, as little as one tissue culture :eve1 of pathogenic viruses in drinking level of Giardio in drinking water? infective dose is able to infect a person. water? What sFecific criteria should be Data from a recent study where healthy What specific criteria should be included in the regulations that would human volunteers were infected by specified in the regulations that would allow States to evaluate if a variance Echovirus 12 suggest that 1 percent of a allow States to provide variances to should be issued to a particular system? population could be infected by 17 certain systems? E. Pathogenic Viruses plague-forming units of this virus. Are satisfactory methods available Because of this. the goal should be to for recovery and nnalysis of classical Between 1976-1882. there were 18 have no viruses in potable water. This is enteroviruses or coliphage and are they reported waterborne disease outbreaks supported by the WHO. Thus, the representative surrogates for pathogenic in the U.S. caused by viruses, with over proposed Rh4CL goal for human viruses? If so, should an RMCL end MCL 5.700 cases. These values are probably pathogenic viruses in drinking water is or a treatment technique be established far too low to represent the actual zero. This RMCL goal would include the for classical enteroviruses or coliphage? number of outbreaks because there is enteroviruses In addition to any others evidence that most of the waterborne for which analytical methods are not yet E Legianel/oe disease outbreaks of unknown origin are available. Because EPA concludes that Legionellae are bacteria that have caused by viruses. Viruses are a class of one virus may have adverse effects. it is been identified as the cause of infectious agents which are extremely able tu propose an RMCL despite the legionellosis. It has been estimated that small [smaller thdn bacteria) and fact that the measurement is difficult. 50.~100.ooOcases of this disease reproduce only within cells of a suitable Because routine, validated procedures occur annually within the United States. living host such as humans. They for detection of the most important and are caused primarily by 1 of the 2B contain genetic material siirrounded by waterborne viruses (hepatitis A agent. currently recognized species of the a protein coat. Pathogenic viruses. by mtaviruses. and Norwalk and Norwalk- genus Legionella. The number of cases delinition, are those that adversely like agents) are not yet technically attributable to drinking water is affect health. The lack of adequate tools feasible, and because of tho potential for unknown. Most people who have for the recovery and analysis of most Intermittent contamination which developed Legionnaires Disease, the pathogenlc waterborne viruses presents difRcultles In effective pneumonia form of legionellosis. were

SO74900 O(H4(03)(12-NOV-85- IS:B.SO) F4701 rev. 6-14-85 Federal Register / Vol. 50, 219 / Wednesday. November 13. 1985 / Proposed Rule- 48955 No. - patients that were immunosuppressed. identified for the organisms in this must be taken to prevent scalding. or were individuals who appeared to be genus. There is great variation in especially in health care situations. more susceptible because of an virulence, and the mere presence of Legionellae may be controlled by underlying illness. heavy smoking, large populations of legionellae in tl-e ultraviolet radiation. Data on ozone alcoholism. or were over 50 years old. In drinking water does not necessarily treatment are incomplete at this time. contrast. while some apparently healthy represent a health threat. For all these In addition to disinfection and heat. individuals have developed reasons. setting national drinking water oth?r procedures may be effective in Legionnaries Disease, outhreaks regulations for legionellae appears to be controlling legioneilae. Hot water tanks involving healthy people have been inappropriate at this time. and an RMCL should be designed to give uniform limited mostly to the milder non- is not.bei1.g proposed. temperatures thrmighout. Dead-end pneumonia form of the disease called EPA has prepared guidance for ' piping should be eliuinated. tlot or cold Pontiac Fever. hospitals and other high risk locales: water tanks used intermittently should Legionellae are abundant in ambient this guidance is summarized below and be disconnected from the system. water. and may survive water treatment, is available from EPA at the address drained. flushed. and disinfected before especially since they are relatively cited at the beginning of this notice. In being reconnected. llot water tanks resistant to chlorine. Even conventional order to reduce legionellae levels in should be drained regularly or at least treatment (i.e.. filtration and drinking water. storage reservoirs be bled to remove accumulated sludge disinfection) probably cannot prevent should be managed to minimize the that may serve as a substrate for growth the passage of a small number of addition of organic matter and growth of of iegioneliae and other micro- legionellae into the distribution system. algae and protoza. Moreover. newly organisms. Taps and showers in unused They may also be introduced into repaired or constructed components of arpas of hea!ih care facilities shculd at drinking water via brokm or corroded the water distribution system must be least be flushed before patients are piping, repair of existing mains, thoroughly flushed and disinfected exposed to then. Finally. faucet sieves installation of new mains, back before being put into operation. Ever: and aerators. and rbbber washers and siphonage. and cross connections. When after fluship2 2nd disinfection. one gaskets in the plumbing system shouid the legionellae enter hot water tanks, cannst assume legionellae have been be used with caution. especially in they can settle to the botom and, under contro!led since design factors in the institutions housing compromised certain circumstances. will proliferate. If distributio,i system may impede the individuals and where hot water is they proliferate, plumbing fixtures such cfficiency of these measures. maintained at temperatures lower tha:i as aerators. water fitings, and showerheads may be seeded, resulting In order to control legionellae growth iu,'F. in colonization and growth at these in hot water plumbing, several Public commen!s are requested on sites. They are often found in the hot approdche? may be considered. Most of whether it is appropriate to propose an water plumbing of hospitals. hotels, and the published data have examined the R!KL and primar) drinking water other buildings, especially in hot water effectiveness of chlorine and/or heat. rr:quiations for legionellae or whether tanks and showerheads where the hot The rnaintrnance of free chloi :ne has t'ie appropriate ai tion is to provide water temperature does not exceed been found effective for controlling guidance. legionallae. Shock chlorination is also 120.F. In many hospitals. the hot water 1;. Heterotrophic Eacteria temperature is maintained at this effective. but unlzss free chlcrine is temperature and below to prevent maintained within a system. the Heterotrophic bacteria are those patient scalding and to reduce energy organism may reappear. Control can which use organic nutrients for growth. costs. probably be achieved if free chlorine l'his group includes virtually all of the There is good epidemiologic evidence levels in the hot water are maintained bacterial pathogens as well as many from several hospitals that Legionnaires above 2 mg/l, but at these levels other innocuous bacteria. The Disease is transmitted by aerosols of corrosior! of pipes may occur. Successful population dengity of these bacteria in potable water from showerheads eradicaiion has been repwted with 3 water is often meastirod by the Standard containing legionellae. Other sources mg/l chlorine in the hot water mystem Plate Count (SPC) procedure. as implicated in disease transmission are for 10 days. followed by a 1.5 mg/l described in Standard Xfethods for the aerosols from cooling towers a:id maintenance level. With this treatment. Examination of LVater and Wustewater. whirlpools. Inhalation of aerosolized only a slight increase in corrosivity was The 16th edi:ion of :his book changes potable water is probably the primary found. Undoubtedly. the level of the SPC designation to tleterotrophic rout6 of infection, although ingestion ISa chlorine found effective will depend, in Plate Comt (HK). possibility. part. on the design criteria of the Primary reagons for considering a Analytical tools exist for recovery and plumbing system. A pertinent facet in, regulaticn for heterotrophic bacteria enumeration of these organisme from controlling le@onellae is the difficulty of include the following:. plumbing systems. However. these are maintaining a rhlorine residual in hot Many heterotrophs in water are not yet very efficient for selectively water. This problem can be minimized opportunistic pathogens in one recovering and enumerating legionellae by using either a closed recirculating study). There is some evidence that from drinking water. system or a continuous-flow numerous hospital-acquired infections Because of the ubiquity of legionellae proportional chlorinator on the hot have been caused by waterborne in ambient water. their proliferation water system. opportunistic pathogens. Thus. a hiRher primarily at warmer temperatures. their Heat shock (le0 'F for 1 hour) may bacterial density. as measured by the relative resistance to chlorination and eradicate legionellae in hot water tanks HPC procedure. may reflect a higher ability to colonize in plumbing systems. nnd is a temporary measure which must level of pathogens in the water which control is probably more appropriatc at be carried out routinely to be effective. are able to cause disease in the locations where susceptible populations Maintenance of hot water at 130 'F or compromised population. reside, rather than at the waterworks. higher apparently controls the oganism. High HPC decsities. or sudden More significant, however. is the fact while lower temperatures may not. If inc-.ases of Hpc density. may indicate that virulence factors have not yet been legionellae are controlled by heat. cam water quality deterioration. Thus. this

F47m rev. 8-14-85 46956 Federal Register / Vol. SO, No. 218 / Wednesday, November 13, 1985 / Proposed Rules group or organisms can be used to Should an RMCL and MCL be set watere substantially reduces the provide warning of a filter bed for HPC? Upon what basis and what potential for waterborne disease breakthrough. monitor the effectiveness level? outbreaks. As previously discussed, of disinfection throughout the Should HPC be included in the recent studies suggest that actual distribution system provide a method for monitoring requirements for total disease outbreaks may be much higher monitoring the condltlon of point-of-use coliforms such that HPC could not than reported. water filters and provide other exceed a certain density in order to Rapid granular filtration. in use since monitoring data. In some of these areas, have valid total coliform results? What the 18ms, can remove between 80-88.8 HPC monitoring can be more level would be appropriate? percent of the bacteria and protozoan informative than total coliform H. Treatment Technique Requimments cysts and 80-89 percent of the viruses monitoring. For example, in research from source water. Slow sand filtration, studies of point-of-use filters, coliforms Discussed below are possible in continual use from the early 18th are rrirely found in the effluents. The treatment regulations that EPA is century, can remove M.Bpercent of growth or potential growth of consldering for the next rulemiking. The the bacteria, and viruses and 90-99 opportunistic pathogene or even primary regulations are not being proposed at percen! of protozoan cyete. A third type pathogens could be better signalled by the present time and are preeonted for of filter, diatomaceous earth (diatomite), higher HPC densities in the effluent. the purpose of public comment. used since World War 11, can remove Thus, HPC monitoring can be a useful 1. Mandarory Fillration and Disinfection 90-98 percent of the bacteria, 95 percent nupplement to coliform monitoring. of Surface Water for Microorganirm of the viruses, and W percent of the The NAS stated that HPC is a EPA is considering a regulation cysts. Percentage removals for filtration valuable procedure for assessing the without pretreatment (Le., coagulation. bacterial quality of water. and that a requiring the filtration and disinfection of all surface watere before distribution flocculation, and settling) are extremely density lees than 500/ml is attainRble by variable, ranging from 0-90 percent for water systems [Drinking Water and to consumere. This regulation would provide protection against a myriad of bacterio and cysts and 0-50 percent for Heollh. 1977. Vol. lj. viruses. Higher HPC densities may interfere diseme-producing microorganisms with total coliform analysis. Several which can frequently be found in Beeldee provldlng a barrier to published articles have indicated tha! emblent water used as drinking water organisms, especially for Giardia. non-coliform bacterial densities greater supplies. As discussed previously, a viruses. and other pathogene relatively resistant to disinfecticn, filtration than 500 colonies/rnl can suppress search in finished drinking water for coliform growth with both the each of these primary and opportunistic reduces the level of particulr'e matter membrane filter and multiple tube pathogens would not be technologically that may protect microorganisms from fermentation procedures. There is also or economically feasible. The disinfectants, reduces the level of toxic strong evidewe that drinking water concentration of pathogene In water particulate matter. and reduces short- samples containing high non-coliform would usually be sufficiently small so as term fluctuations in water quality. bacterial densities resulting from to requirc large-volume samples. Many Formation of trihalomethanee and other regrowth during sample transit may are so fastidious that only highly by-products of disinfection are also reduce the chancea of detecting total specialized laboratory techniques can reduced by filtration which reduces the coliforms. be used lo recover and detect thew. if quantity 3f precureors that can react Although there is some evidence that they can be detected at all. This is true with the disinfectant. high heterotrophic bacterial densities of the hepatitis A agent, rotnvlrus, Filtration and disinfection reduce are of concern, the Agency believes that Norwalk and Nom alk-like agents. and contamination continuously and deal it would be premature to propose an Giardia. Unfortunate:y, total coliform with the possible events of periodic RMCL given the lack of conclusive data bacteria are inadequate as an indicator contamination. Without treatment. regarding the link between opportunistic for the presence of these organisms. monitoring for contamination is pathogens in drinking water and Thus, EPA may propose a treatment necessarily intermittent and the nosocomial (hospital-acqllired) requirement In the next rulemaking. microbiological quality of the drinking infections. 1n.lead of proposing an Of the approximately 14,000 water is not known for more than a day RMCL MCI and monitoring/reporting community water systems in the US. or more and sometimes much longer. requirements, the P-gency is conaidering which use surface water, about 78 This is especially true of small systems !ncorporating a level of HPC control into percent practice full conventional where total coliform monitoring is quite the told coliform monitoring treatment and about w percent employ limited. In 1982, about 24 percent of the requirements since high densities of at least disinfection. Between 1mand public water systems violated coliform HPC interfere with coliform analysis. 1980, there were 18 reported waterborne monitoring requirements at least The monitoring requirements for total disease outbreaks with over 11,000 intermittently and 14 percent violated coliforms could specify that a certain cases in localities served by surface turbidity monitoling requirements. percentage rc the samples collected for watere receiving chlorination only. This Furthermore, as noted previously. total coliform analyses would also he representad 35 percent of the total coliform monitoring is not a adequate Analyzed for HPC: if HKwere greater number of outbreaks and 44 percent of indicator of all possible pathogens. than some level (e+. 500 colunies/ml). the cases associated with surface wnter Any filtration and disinfection of the total coliform analyses would not be supplies, everl though disinfectad-on:y surface supplies would not neceesari!y valid. This would provide a measure of surface water systems represent less require all systems ro adapt these quality assurance not previously than 17 percent of the total number of treatment methods. The SDWA (section required in tha Interim Regulationa. surface walw systems. Durlng that same 1415) allows systems to receive a Monitoring for HPC would also indicate period, 6 disease outbreaks (11% of the variance from the requirements if treatment effectiveness and possible total) and over 200 cases were certain conditions are met. All systems deterioration of water quality. associated with untreated surfsce water would be required to install filtration Public comments are requested on the supplies. These data strongly suggest and disinfection unless the system following: that filtration and disinfectlor! of surface demonrtrates to the satisfaction of the

F4701 rev. 6-14-85 Federal Register / Vol, 60, No. 210 / Wednesday. November 13. 1985 / Proposed Rules 48857

State that the treatment technique is not reducing microblal and particulate Public comment is requested on the necessary to protect the health of contamination of the underlying wale!. f ol I o w i ng: persons because of the quality of the The number of reported disease Should a treatment technique raw water source of the system. Criteria outbreaks and cases associated wlth requirement be established such that would be provided in the regulation untreated ground water supplies are systems using ground water would be which the system must meet in order to subatantiolly greater than those for required to provide disinfection? Upon receive a variance. treated ground water supplies. what bnsia? The practice of filtering surface water According to published date. What specific disinfection is supported by a number of communities served by unhealed technology should be Included in the professionai groups such as the AWWA: ground water have had 3.7 times as regulation? "The American Water Works many cases of illnesses. Between 1971- Association (AWWA) strongly supports 1982, untreated well water was Should these treatment the practices of filtration of surface astrociated with 110 disease outbreaks requirements apply to non-community water used as sources of public water and over 8500 cases of illnessea. If drinking water systems? supply, disinfection of public water untreated spring water is added to this What criteria should be Specified supplies, including the maii.lenance of total. the values are 126 outbreaks and for the issuance of variances? residual disinfection in the distribution over 9800 cases. In 1982. untreated VII. Inorganic RMCLs system,...... (AWWA, 1983. AWWA ground water WQOresponsible for 28 Officers and Committee Directory, percent of all reported waterborne The Interim Regulations contein MCLs Policy Statements and Official disease outbreaks and 10 percent of all for the following ten inorganic Documents. p. 74). In addition, a waterborne illnesses. The etiological chemicals: workshop convened by the EPA's Office agents implicated in these outbreaks CmUmnurt I MCL. mpl1 of Drinking Water, in conjunction with were the hepatitis A agent, Yersiniu. .I---. the American Society for Microbiology, end Giordio; in 5 orrtbreaks the agent ', ArwnK ...... ! 005 to advide EPA on a variety of drinking was not identified. Barn...... I 1 water issues, strongly recommended the Adequate disinfection reduces ...... ' 0010 filtration of surface waters (Assessment contamination continuously and deals ...... of Microbiology and Turbidity with periodic contamination. Similar to Standards for Drinking Water, Dec. 2-4, surface waters. monitoring for 1981, July 1983, EPA 670-W3-O01 J. contamination 1s necessarily Public comment is reqliested on the intermittent, especially for small following: systems. Moreover, in 1082, about 24 Should a treatment technique percent of the utilities violated coliform requirement be established such that monitoring requirements at least Monitoring and reporting system using surface waters would be intermittently and 14 percent violated requiremcnte were also included in the required to use filtration and turbidity monitoring requirements. Interim Regulations for sodium and disinfection? Upon what basis? A variety of disinfectants are corrosion. What specific filtration and available. Cunently. the best are The ANPRM (48 FR 45502) listed 23 disinfection technologies should be chlorine (as hypochlorous acid), ozone. included in the definition of a lOCs under consideration for Primary and chlorine dioxide. All three have Drinklng Water Regulations. RMCLs are "filtration" and "disinfection"? For excellent biocidal activities against proposed for 11 iOCs (one of which wee example. direct filtration? slow sand bacteria and viruses. For inactivation of filtration? not listed in the ANPRM-nitrite). one protozoan cysts, ozone is excellent. IOC (fluoride) will be included in a Should these treatment chlorine has only moderate biocidal requirements apply to non-community separate proposal. and 6 lOCs (cyanide. activity, and no published data are yet molybdenum, nickel, silver. sodium. and drinking water systems? available for chlorine dioxide. Chlorine What criteria should be specified and chlorine dioxide residuals can eulfate) have been determined that would provide guidance in the persist in the distribution system. ozone inappropriate for regulation based upon issuance of variances? residuuls cannot. Besides these three limited health effects data and/or disinfectants. others are being used or occurrence in drinking water. Five lOCs 2. Mandatory Disinfection of Ground (antimony, beryllium. thallium. Water have been suggested for use. These include chloramines, iodine, bromine, vanadium and aluminum) will be EPA may also propose, in the nexl and ultraviolet light. A treatment addressed at a later date and one IOC rulemaking, a treatment regulation regulation will recommend the types of (zinc) has been determined requiring the disinfection of all ground disinfectants appropriate for use, the inappropriate for regulation based upon waters before distribution to the range of acceptable disinfectant EPA and the National Academy of consumer. Many of the same concentrations, minimum contact times. Sciences (1977 and 1980) reviews. microorganisms that occur in surface and possibly the minimum and For the 11 inorganic chemicals for waters are also found in ground waters. maximum residual concentrelions in the which RMCLs are proposed. the Because a search for each pathogen is distributlon system. Variances would be Administrator has determined that not technically or economically feasible, considered in those cicumstances where human exposure to these lOCs in and because the presence of some are a system is able to demonstrate to the drinking water may have an adverse not adequately signalled by the eatisfaction of the State that the source effect upon the health of persons. presence of coliforms, a treatment water is of sufficiently good quality IO Table A presents the proposed RMCLs technique regulation may be proposed. obviate the need for disinfection. Like for the 11 10Cs. Table 9 summarize,a the Filtration of ground water nuppliee, the surface water regulation, criteria to short-term assessmeets for those while encouraged, may not be proposed assist in making variance chemicals for which RMCLe are as a requirement because the soil acts determinetions would bs provided if a proposed and Table 10 summarizes the as a natural filter, thereby usually regulation Is proposed. short-term aseessments and provisional

SO74999 OO57(03)( I?-NOV-85-1 S:20:56) F4701 rev. 6-14-65 AADls for those chemicals for which interprelatlons of data and varying trained personnel to conduct the RMCb are not roposed. aseumptlons. In some caoes, new data analyses. Specific analytical methods Presented in tks section are (I) a may have become avsilable resulting in for each contaminant will be proposed discussion of analytical methods the derivation of an AADl which differs as part of the MCL proposal along with available for measurement of lOCe and from the earlier calculated values. This specific criteria for the determination of (2: separate discussions for each IOC on section closes with a description of the acceptable performance for those (a) the occurrence In drinking water and toxicological basis for the proposed laboratories conducting compliance the relative contributions from drinking RMCL This include8 calculations of analyses. water. air and food, ilnd (b) the potential Adjusted Acceptable Daily Intakes health effects of exposure. In this notice, (AADl'e) for threshold toxicants and, in EPA is presenting a summary UI those addltion, a risk assessment for anolyticel methods that appear to be substances that are being proposed for available. In the MCL proposal, EPA iegulation as potential human wil: propose methods that have been carcinogens. Issues are identified for Annv ...... 0.10 0050' determined to be economically and which ublic comments are requested -(- ...... 71rmLgn(brrl technologically feasible. on eacR of the IOCe. The information and lono mum) w* In the discussion of health effects, @.nun...... 10 15 presented here is summarized from the c.dmm ...... 0 018 OW5 information on 1-day exposure, 10-day supporting documents on analytical cham...... 0 17 0 12 exposure and chronic toxlcity effects is methods. occurrence, and health effects coppr,...... 13 138 included. In addition. a summary of Laao...... oozo referenced in Section X. Mawy ...... 0005 Ow1 health-related guidelines prepared by ma...... 100 100' other groups and organizations is A. Availability of Analytical Methods mate...... 10 10' presented for each IOC. Levels that have Analytical methods are available for s*M\...... o im 0 015 been calculated by the WHO,the NAS the determination of all the lOCe for and EPA'e Office of Water Regulations which RMCLa are propoeed in this and Standards (Water Quality Criteria) notice with the exception of asbestos. have been included. In several Preliminary assessments have been instances, these values differ from the conducted of existing methodologies to proposed AADIe. This is due to several determine their suitability in terms of diffcrent factors. including the use of performance, coal. complexity, and other different uncertainty factors, different factore such as the availability of

TABLEB.-~ORT-TEAM ASSESSMENTS FOR 1x9FOR WHEH RMCLS ARE ALSO PROPOSED

loar OWO LQpl(."n' coc. ---__.I___. 1.D.v (mol0 !?-/r)- Qwd AM marl AM am Awl

&lor& ...... 005 005 0.05 005 005 005 ...... NA NA NA NA NA MA ...... NA NA NA NA NA MA ...... 0043 0 150 0.m 0029 NA MA ...... NA NA 1.4 5.0 0.24 OM ...... 1...... 1.3 1.3 NA NA NA NA Lead ...... NA NA NA NA NA NA Msmr)...... NA NA NA NA NA NOaIe ...... NA ' 10 111 HA NA Me...... "...... NA *l 11 NA MA ...... "...... NA 0.041 0.144 NA NA

NA-Nol -.law. Adsqp10 domoom drU m W myIw. AMvmt daiva! (a Vu nnl bnga brmon 0) .r~ounb onrb..d lo ba pokck. h hrw cnn 'The bngsr4n nn&R no( dkcuDsd h UN h&i&d Fc) Mtce vbap buc b* ntrau* (or b* m drcurwd h b* Adrlo* dauma 'hnd on a 4 kg Mmd. Fa raDN* ma b* MdIh Mnmq k cllb.1.lta?nes.

......

N*-NO( A*.Y.W. AdOWota domrparu d.u m no( m.kutanl brk.d (a b* m logr &nhlk mnaUwed lob. h -. 'FI Ngh fhh hdn*nhon .odun res- dah.€PAM mho pmpm reon6uy nadrQ band c9a,wnh(* ~Nfy. 'Favoluuon d me d.n( aa a nnwwa rbpop~.aon. 'gaud on wta and oda. :ed.u00n ol port p.cpnraa, hUNamania,.)rtm.*hkumrarldbrrEaddrt. far rcQdrlnrrdrd. RanavlAmrnM.onhmrnnWI*.hnmdk-

Table 11 provides a listing of several Two method validation studlee have coupled plasma (ICP)atomic emission analyticel methodologies Tor the lOCs been conducted for the furnace atomic spectmmetry techniques. Analytes end estimated detection limits. absorption (AA) and the inductively include all the metals listed In Table 11

s-074999 00J8(03XtZ-NOV-8S-IS:20:S8) F47M rev. 614-85 Federal Register / Vol. 50. No. 219 / Wednesday, November 13, 1985 / Proposed Rules 46859 analyzable by these techniques. Other Environmental Monitoring and Support asbestos. These data will be the basis performance related data are being Laboratory in Cincinnati. Ohio [EMSG for the analytical methods and gathered from ongoing performance CIN) for all lOCs included in this RMCL performance criteria which will be evuluatlon studies conducted by EPA's proposal, with the exception of proposed when the MCLs are proposed.

TABLE1 ~.-ANALYIICAL MEWOOSFOR IE'S

Alrmnum M Flwr* ...... 2021 3OJCaD j 0 857-79 DOTE ...... 2022 '3: 1 3M I ...... 450 Zoo7 kunc: AA. cnan ...... ~...... 20' 2001 JOJE 1 0 2972-78 B M Fvmm ...... 10 2002 3M ICP ...... : AmbntmTMwn*wnE*cbonUYmropl I B.nrm: ...... M F- ...... ICP ...... c.bnm: M FW...... 2131 /30JAaB. , 0 3557-78 A of B M f- ...... 2132 1 30*. . ICP ...... Zoo7 ...... oram IO! M Flm...... ! 0 1887-77 D M Fm...... 1 ICP ...... I ...... I coop: M Flm...... I 200 I 2201 I JOJAof e...... D 1(uM-'7 D. E M fvna...... 101 ZZoZ(3M ...... ICP ...... 80i Zoo7 ...... orrrd.: ,. bMmmom cocamanc ...... i ...... : ...... Aulmupd E*cbodr ...... ' '.'. 5001 ..... '412E...... ! Lrd. 'I I I MF ...... I 1000 ZJ~~!JOJAOTB o 3559-78 A OT o MF ...... I 10 ne2 304 ,I ICP...... 50' Zoo71

Manual cord Vqor lr(maw ...... -knanrtad cord Vqor 1- ...... ~ ...... M Flurr...... -M F- ...... ICP ...... 1, Mkha MFlm...... I MFunc...... 1 ICP ...... Wat.: 1 Cocomrmcafubu ...... 10001 J521: I soalmmw. c.dmm R.bccm ...... 100 35JJ 4tOC I D 3W7-?9 B wOny1.d wurr R.Mm ...... "' " ' I 100 ' JSJ 1 1 I AUt0nmt.d caamall R.bcmn ...... JU2 410 F Heme. SPCbOphO(OmbC ...... I zi: JYI 1419 ...... 2o I 110 i 103 E...... i 20 i 270.2 ...... 10, Zoo7(.1304 ...... I ...... I too . 270 1 1 JOJ A ...... ! o ~(16-82A a a ...... 021 272213M ...... ICP ...... 7501 Zoo71...... emao: ...... l.OOOO\ 37541428C 1 mtseza ...... 3.0000 I J752 I...... :'::.:.::: ...... :::: .... :.:.'/, ...... 20; 27J.t ...... 02, 2732 ...... 10 0 1...... 325 8 ...... 0 142644 A.

B. Proposed RMCLs by-product of the smelting of copper, generally ground waters tend to contain lead, and zinc ores. Areas with elevated higher arsenic levels than surface 1. Arsenic levels of arsenic in geologic materials waters. Arsenic in water can result from Arsenic occurs naturally and is are found throughout the United States. both natural processes and industrial commonly found as arsenic sulphide or mostly concentrated in the eastern activities, including smelting operations, as an impurity in various minerals and States. Some coals, particularly from use of arsenical pesticides. and as arsenate or arsenite. In particular, eastem States, have a high arsenic industrial waste disposal. arsenic is found in oms of copper, lead, content. Analytical Methods. Analytical zlnc, iron, managaneee, uranlum, and Arsenic has been found In both methods avallable for analyzing gold. Most of the anenic produced is a ground water and surface waters; elemental arsenic in drinking water

S-074999 005~03~12-NOV-85-15:ZI001) F4701 rev. 6-14-85 48980 Fderal Redater / Vol. 60, No. 219 / Wednesday, November 13, 1985 / Proposed Rules include the atomic absorption, gaseous The NAS (Drinking Waferand inadequate for evaluation. Arsenic has hydride, furnace atomic absorption and Health, 1883. Vol. V) reevaluted the been classified in EPAs Croup A. inductively coupled plasma atomic toxicity of arsenlc and stated that, according to EDA's Proposed Guidelines emission spectrometry techniques. Research should also be designed to for Carcinogen Risk Assessment, based Human Exponure. Arsenic enters the evaluate the posslbie essentiality of arsenlc upon evidence of human carcinogenicity atmosphere as a result of the smelting of for humans-a requlrement that has been through inhalation and ingestion non-ferrous ores, mostly copper; glass demonstrated in four mammallan species. In exposure. production plants, coal burning the absence of new data, the conciuslon EPAs Office of Research and facilities, and arsenical compound reached in the third volume of Drinking Development commissioned a report production plants may elso emlt arsenic Water and Health remains valid, 1.e. 'If 0.05 (Andelmen, et al. 1883. Feasibility Study to the air. Data collected by EPA and mg/kg of dietary [totall arsenic is also a nutritionally deslrable level for people, then to Resolve Questions of the Relationship others show the level of arsenic in air of Arsenic in Drinking Water to Skin ranges from O.OOOS1.5 ug/ma; the the adequate human diet should provide a dally Intake of approximately 25 to 60 ug. The Cancer. Submitted to Office of Research median value is typically less than 0.01 current American diet does not meet thls and Development, US. EPA] to examine ug/m? Respiratory intake of arsenic on presumed requlremenl' (National Research the available epldemidogic studies a daily basis is approximately 0.12 ug of Council, le80).The unresolved status of thin which looked at the relationship which 0.03 ug would be absorbed, Issue is further reason for malntainlng the between arsenic exposure aid skin assuming 30 percent absorption and current MCL for anenlc. cancer in the United States. The based on a 1881 national average air In addition, the NAS Safe Drinking conclusion of the report SVIIB that the value of 0.008 ug/ma of air and a daily studies performed to date lacked ventilation rate of m? Water Committee stated that "it is 20 therefore the opinion of this committee sufficient power to definitively Arsenic. primarily In an organic form determine if arsenic causes akin cancer. is a normal constituent of food. that 0.05'mg/l provides a sufficient Seafoods tend to have particularly high margin of safety. . . ." Based on the However, the report stated that the arsenic levels. Meat, fish, poultry, grain, specific recommendations of the NAS, precursore of skin cancer (increases in and cereals also contain arsenic. The EPA proposes that all Health Advisories skin pigmentation and callous for arsenic be 0.05 mg/l. formation) were not seen in these FDA estimated in its 1978 market basket stuc lee and these precursor effects survey that adults consume 61.5 ug/day A provlslonal AADI was calculated of arsenic in the diet. based upon an animal study (Heywood, would normally be seen in cases of Sixty-three community water supplies R. and R.J. Sortwell, 1979. Arsenic arsenic-induced skin cancer. in the United States have been reported Intoxication In the Rhesus Monkey. Based upon the spocific lo exceed 50 ug/l of arsenic. Limited Toxicol. Lett. 3:137-144) In which recommendations of the NAS. EPA data from two federal surveys indicate adolescent and infant Rhesus monkeys proposes that the RMCL for arwnic that water supplies using ground water were exposed to arsenic for one year. A remain at the current MCL of (r.t~% mg/l. had arsenic present above the detection NOAEL of 3.74 mg/kg/day arsenate (2.8 This level is below the concentration at limit more frequently and at higher mg As/kg/day) was selected, with an which toxicity is demonstrated und is in concentrations than supplies using uncertainty factor of 1OOO and the range which may bt- esse:tid for surface water. Of 330 ground water consumption of 2 liters of water per day humans (Drinking Watcr and tl~!aIfh. supplies sampled in tile two surveys, 55 factored in. A provisional AADl of 0.10 1983. Vol. VI. (16.7%) had levels above 5 ugll; of the mg/l was determined from this study. EPA cmeidered using 0.10 mil/l as the 115 surface water supplies, only 2 (1.7%) Arsenic has been shown to be proposed RMCL baaed upon the had levels above 5 ug/l. mutagenic in several test systems and to provisional AADI. It was determ'necl Health Effects. Arsenic compounds induce chromosomal aberrations in in that the RMCL should not be based have been shown to produce acute and vivo and in vitm systems. upon this data. because an insufficient chronic toxic effects which include Carcinogenicity studies with laboretory number of animals (4 per dose gmup) systemic irreversible damage. The animals have reported conflicting were studied. trivalent (+3) compounds are the most results. Several studies have reported an Zero or some other value for the toxic and tend to accumulate in the increased incidence of bronchlogenic RMCL based upon the carcinogenic body. Chronic animal studies have carcinomas in rats exposed to an potential for arsenic was also shown body weight changee. decreased arsenic-containing pesticide through considered. However, studies of blood hemoglobin. hepatic damage and intratracheal exposure. In humans, drinking water related arsenic ex:x;.eure kidney damage. tumors of the skin, lungs, genital organs have not detected increased risks via There is evidence that arsenic is an and visual organs have been associated drinking water in the USA. Because essential element in certain animal with nrsenic exposure. evidence suggests that arsenic may be species and potentially in humans. The LARC evaluated arsenic and an essential element, eettlng the RMCL Arsenic at low concentrations injthe diet stated that there is evidence that at zero would not take Into account the enhances some parameters of growth arsenite and arsenate cross the placenta possible beneficial effects from arsenic and development in animals and it has In mammals and that sodium arsenate exposure. been suggested that arsenic may be an and arsenite have embryolethal effects The WHO guideline for arsenic is essential element for humans (NAS, and teratogenic potential in several 0.050 mg/l which is the same level that 1980. Drinking Water and Health, Vol. mammalian species. The IARC EPA is proposing for the RMCL This 111). classifled amenic compounds in Croup value was based upon human data EPAs Risk Assessment Forum is 1; inadequate evidence for which suggests that a concentration of currently evaluating the nutritional carcinogenicity In animals and sufficient 50 pg/I of arsenic per liter is not requirements for arsenic. A evidence that inorganic arsenic associated with any adverse health comprehensive literature search compounds are skin and lung effects. In addition, the WHO stated examining the available data on the carcinogens In humans. They also stated that at an arsenic concentration of 50 possible essentiality of arsenic is being that the data suggesting an increased p,g/l, the contribution made by water to carried out. risk for cancer at other sites are the daily intake will normally be about

€74701 wv. 6-14-85 Federal Redeter / Vol. 50, No. 219 / Wedneeday, November 13, 1985 / Proposed Rules 48961 one-half to two-thirds and for very low Analytical Methods. The analytical outdoor exposure. The daily exposure dletory intakes of arsenlc, the determlnatlon of asbestos in drinking through Inhalation of ambient air would proportlon provided by water may be water presents a unlque problem. be approximately 3000 fibers/dny at a somewha' :righer. The WHO concluded Asbeelos is a generic designation for a ventilation rate ol 20 ma lor the adult that arsenic in drinking water will group of minertlls of various male. normally be the main source of compositlons. Therefore. the accurate No information wan available from Inorganic arsenic. determination of aebestos requires the the FDA on the occurrence of asbestos EPA's CAG hae calculated excess Identification, characterization and in food. Some wines have been shown to cancer riek values for arseriic (U.S.EPA. measurement by counting the number of contain as much as 84 million fibers of 1980. Ambient Water Quality Criteria particles possessing the required fibrous asbestos per liter (MFL). for Arsenic. EPA 440/~2).CAC ehape, crystalline structure and Levels of asbeetoe fibers in drinking calculated that concentratlone of 22 ng/ elemental compoeition. The beet existing water have been summarized by EPA I, 2.2 ng/l, and 0.22 ng/l would result in technique for this purpose conelste of (1960) for 408 cities in 47 States. Puerto an incremen:el Increase of cancer risk separation of fibers and quantitation by Rico. and the District of Columbia. The over the lifetime 01 10-5 IO-'and lo-? tronsmlssion electron microscopy and distribution of reported asbestos reepectively. Theee valuee were identification by X-ray diffraction. The concentrations is presented lielow: calculated baeed upon a study of accuracy of this method is highly increased incidence of skin cancer in eensitive to the quality of the water -1 amrmconuntrabcn. IO' 8 Numtm Psrcnnb humans in Taiwan (Tseng, et el. sample and to the presence of I*/ I 1 OICIlLS I lese. f -!?L Prevalence of Skin Cancer In an interfering subetances. A major c-- 8.lad.uc(mmr ...... I 1t1I 19 Endemic Area of Chronic Arsenicism in drawback is the Initial capital outlay ol ...... $~,OOO tl ..I 210 ' 5'1 Taiwan. Jour. Natl. Caner Inet. 4~453). approxlmateiy for equipment. I IO 10 ...... 33 I 0 EPA is proposing to regulate orsenlc the analytical cost of approximately >IO ...... j 40i 10 because of the potentlal adverse health per sample and requirements for effecte and its wldespread occurrence. epecialized facllitles and personnel. In 1981. EPA summarized the results Based upon the NAS recommendations. Thue, monlloring le not considered to be of a nationwide sampling lor asbestos in an RMCL of 0.050 mg/l le proposed. technologically and economically drinking water from 100 systems. Comments are requested on all of the feasible for all types and lengths of Samples were taken from a issues outlined below, and comments asbestos fibere for compliance purposes repreeentative point in the distribution are epecifically requested on the In public water systems. Three different approachee have been syetem of each utility. Levels above appropriate level for the RMCL detection of 0.08 MFL were found in Questions for Comment: inveetigated to develop a eimpler. Caster and cheaper measurement method for twelve of the 100 eysleme. Levels ranged 1. How should the proposed from 0.385 to 1.071 MFL. Theee data and nutritional essentiality of arsenic be asbestos. These approaches depend upon light scattering properties of other data from various State studies consldered in determining the RMCL? particulates (turbidimetric and magnetic iridicate thet asbeetoe occurs in various 2. le 0.050 mg/l an appropriate level alignment-light scattering methods), or drinking water supplies acrose the for the RMCL, or should the provisional surface propertiee of chrysotile asbestos country as a result of asbestos in the AADl(0.10 mg/l) or another value be which le selectively extracted into iso- raw water supply or a8 a reeuit of used? octane in the presence of a surfactant corroeion of aebestos-cement pipe in the 3. Should areenlc's carcinogenic (two phase liquid eeparation method). distribution system. potential alone be ueed in setting the The most promising method is the one Human exposure to asbestos in RMCL? based on mapnetic alignment-light drinking water occurs primarily via 2. Asbestos ingestion but exposure via inhalation scatterine.Optica microscopy may be used to can occur as a reeult of the use of Asbestos is a commercial term screen water sample8 to measure fibers humidifiers and possibly ehowers. applied to a group of highly fibroue. above a certain length. Fibers with a However, data are limited on these hydrated silicate minerale. These minimum length of 5 micrometere and sources of exposure. minerale separate into long, thin, strong about 0.5 micrometere in width can be Health Effects. A wide range of fibers that are heat resietant and measured ueing this method, with the effects have been observed following chemically inert. and which possess analytical costs estimated at $SO-$IOO exposure vie inhalation to asbestos sufficient flexibility to be woven. per sample and an initial outlay of particles. This Is in contraet to exposure Aebestos minerale belong to the approximately $1,sOO for an optical via ingeetion where the only effects' serpentine or amphibole groups. The microecope. This technique reported in animals at very high levels amphiboles are further divided into the characterizes fiber shapes only and does were changes in the mucoeal lining cells' orthorphobic crystal system and the not discrlminale between asbestos and of the ileum and changes in the colon, monoclinic crystal system. Of the non-asbestos types. However, the rectum and small intestine. commercially mined and processed technique could be useful for screening Inhalation studiee have shown that asbestos minerals. chryeotile (serpentine to determine which samples should be various forms of aebestos have group) accounts for 95 percent of analyzed more intensively using produced lung tumors and mesothelioma production. transmission electron microscopy or for in laboratory animals. The majority of There are literally thoueands of surveillance after the nben in a water asbestos ingestion studies have failed to recorded uses of asbestos minerals in supply had been characterized by x-ray produce carcinogenic effects in animais. the US. 'fie major uses, however, are in dlffraclion or transmission electron The National Toxicology Program (NTP) production of cement producte, floor microscopy. Investigated the carclnogenic potential tiles, paper producte. paint. and Human Exposuw. The NAS (1984) of the ingeetion of amosite and tremolite caulking: in traneportation-related have reported an air concentration of asbestos In rats. No toxicity or increase applications: and in the production of esbestos of 0.oOW tq/cm' as typical to In neoplasia was observed in tremolite- textlles and plastics. an urban dweller. combining indoor and exposed rats, while signincant increases 46882 Federal Register / Vol. 50, No. 219 / Wednesday, November 13, 1985 / Proposed Rules

In C-cell carcinomas of the thyroid and resolved at this time. The Chronic wlth the ingestion of asbestos In rnonocytlc leukemia in male rats were Hazard Advlsory Panel on Asbestos drinking water. The CAG IU.8. EPA. ubserved in the amosito-exposed group. (US. CPSC Draft Report, 1983) has 1981). Ambient Water Quality Crllerla The NTP concluded that: (1) The stated the following: "Lung cancer and for Asbestos. EPA 440/S-60-022)and the biological significance of the C-cell mesothelioma constitute the majority of NAS (Drinking Water and Health, 1883. cnrclnoma In relatlon to amoslte asbestos produced cancers. The Vol. V) consldered much the same data exposure is dlscounled because of a aasociatlon of these mallgnancies wlth of occupationally exposed workers with lack of significance when C-cell asbestos exposure is firmly established. GI tract cancers. but use a sllghtly adenomas and carclnomes were Some other forms of cancer, partlcularly different method of calculating the comblned and the positive effect was digestive tract, oral pharyngeal, excess cancer risk values. The estimated not observed in the amosite plus laryngeal, and kldney have, In some levels which would result in Increased preweaning Ravage group, and (2) the large studies, been found to be lifetlrnu cancer risks of io-? IO-? and biological slgniflcance of an increased Increased; there are dlsagreemonts 10"calculated by CAG (1980) are Incidence of mononuclear cell leukemia among Panel members as to the stiungth 300,000 fibers/l. 30,000 fiber& and is questlonoble because of a lack of of the evidence associating this group of 3,000 flbersll, respectively. stntistical significance in the amosite cancers with asbestos exposure." A Corresponding numbers for males Rroup whon evaluated using life table report prepared for the Health and calculated by the NAS 11983) are 11O.ooO annlysls. Safe1 Commission of the United fibers/i, 11,ooO fibers/l and 1,100 Recently. NTP has reported the results Klng dom examinod the available fibers/l. The more restrlctive levels on the ~OXICOIOR~and carcinogenesis of evldence on the health effects of inhaled celculated by the NAS compared to chrysollle aebeetos in FW/N rats (NTP. asbestos and concluded, "In particular, CAG are prlmarily due lo the 1984. Toxicology and Carcinogeneale there are no grounde for believing that application of two different Studies of Chrysotile Aebeetos In FW/ gastrointeetinal cancers In general are assumptions: N Rats. Draft Report). In thin report, the peculiarly likely to be caused by (1) The NAS assumed that 30 percent NTP hae concluded that "there was asbeetoe exlJsure. The Increase in of the inhaled fibers were eubsequently some evidence of carcinogenicity" in relative riek for gastrointestinal eitee Is swallowed, where the CAG assumed male rate only that were exposed to one slmilar to that for other sites; and thelr that 100 percent would eventually be percent Intermediate range (IR) selection for special attention appears to cleared and Ingested. r'rrysotile asbestos In the diet for the have been dlctated largely by the (2) The NAS assumed a conversion lifetlme of the animals. This prelimlnary findings in one study and the fact that factor of W for optlcal microscopy to conclueion was based on the following they are common, so that a given tranemiesion electron microscopy, obeervations: (1) A significant Increase observed relatlve riek may be where the CAG assumed a factor of 200. in benign eplthellal neoplasms statietically significant for theee sites The avallable information on the risk (adeiiomatous polyps) in the large but not for others." of developing gastrointestinal tract intestine of IR chrysotile asbestos male The IARC hae claesified asbestos In cancer assocleted wlth the Ingestion of rats (9/250; 3.6%) when compared with Group 1; sufficient evidence for asbestos from drinking water Is limited. the incidence of eplthellal neoplasms carcinogenlcity In animals md humans. Risk projections based upon ingestion (benign and mallgnant combined) of the This cltieslfication is based upon studiee would appear to be more large Intestine In thz pooled male inhalation data. Asbestos has been appropriate than Inhalation for control groups of all the NTP oral clanelfled In EPA's Group A, according exposures vla drinking water. CAG asbestos lifetime studies (3/524; 0.6%). to EPA's Proposed Guidelineu for (1984) has derived an eetimate of the (2) the incidence of similar lesions In the Carclnogen Assessment, based upon risk for aebestos by InJestlon based emall lntestlne or glandular stomach of evidence of carcinogenicity in humans upon 8 draft NTP (1984, draft report) flvo additional IR chrysotile male rats, through Inhalation exposure. ingestion study of chrysotile short range and (3) the rare occurrence of epithelial Several epldemiologlcal studlea have (98% 1Oum; with -14%> 100um) fibers for male rats and 011,777 for female) is associations between asbeetos fibem in in animals. The results of this study standard. drinking water and gastrointeetinal showed no evidence of carcinogenlcity There have been a number of cancer. Marsh (Environ. Health Persp. for the short-range fibers in either male epidcmiologicel atudies which showed 1983.53:4@-56) revlewed and evaluated or female rets and no evidence of gastrointeetinal cancer to be aeeociated thirteen epidemiological studies of carclnogenlcity for the intermediate with occupational exposure to asbestos. Ingested asbeetos in five areas of the range fibers in the female rats. However, The conelatency of an Increased cancer United States and Canada for the risk there was an Increase in benlgn polype riek at extrathoraclc sites and its aeeociated with ingestion of water of the large inteetine for the male rets magnitude, either In abeolute or relative containing asbestoe. He concluded that ingesting the Intermediate range fibers terms, in leee for cancer at other sites even though one or more studies found (>YO um) at 1 percent of the dlet. than for lung cancer. Neverthelean, assodation between asbestos In water Although not statietically eigniflcant many studies document significant supplies and cancer mortality (or compared with the concurrent controle, cancer risks at various gastrointestinal Incldence) due to neoplasms of various the incidence of these neoplasms was eites. Even though theee studlea organs. no individual study or hlghly aignlflcant when compared with document definlte evidence of aggre atlon of studles exists that would the incidence of eplthellal neoplaems aesociation of observed gaetrointestinal enlablah risk levels from Ingested (benign and malignant comblned) of the cancer risk and elevated lung cancer in asbestos. lege inleetine In the pooled control workers, the question of whether the EPA's CAG (1980) and the NAS (1983) groups of all the NTP oral asbestos observed increased risk of have extrapolated the results of cohort lifetime studles. If Indeed a cause/effect gaetrointestinal cancer is due to the studies of populatlons occupationally can be deduced from thls experiment. ingestion of inhaled aebeetos in the exposed vla Inhalation in order to CAG calculated, based upon the one-hit occupationally exposed workers is not eetimale the rotentlal risk aseociated model, that 7.1~10~.7.1xlO'and 7.1~10~ Federal Reglsler / Vol. M), No. 218 / Wednesday, November 13, 1885 / Proposed Rules 48989- fibersli, would result In a Ilfetlme the NTP rtudy was sufficlent to proposed based upon the wldespread excess cancer risk of io-? 10-'and lo-? conclude that carclno enlclty was occurrence of esbestos In public water respecllvely. These levels are calculated demonstrated under t I! e condltlons of supplies. data showing that asbestos is for the Intermediate range chrysotile the study. The SAB concluded that the carcinogenic In humans through fibers only. As such, the levels are much data were equlvocal and reaffirmed Inhalatlon exposure, end deta showlng more reslrictlve than they would have their 1684 concluslons as summarlmd that fiber lengths greeter than 10 pm been hod they Incorporated the study above. may be carclnogenlc through ingestion using the short range chrysotile fibers. EPA has considered two mein exposure. EPA will roconsidcr this The short range chrysotlle fiber study regulatory options for asbestos in opllon based upon any new data end showed no effects wlth W times the drlnklng water. The first option conslrls the public comments received. number of fibers as the lntennedlate of not proposing a primary regulatlon for Questions for Comment: ranRe study. If the short ranRe study had asbestos, due to the lnconcluslve nature 1. Are there sufficient dote upon been included with the data from the of the data. Anlmal sludles (except for which to regulate asbestos as a possible Intermediate range study had been the recently reported NTP study) have human carclnogcn by ingestion includad with the data from the not uhown a correlallon between oral (Category II)? intermediate range study. lo~elswould exposure to asbestos and carcinogenic 2. Is there a sufficient basis lo: EPA to have been 81 least10 tlmed higher (Le., effects and epldemlologlc studies regulate asbestos fibers exceedinR 10 lesr restrictlve). Conversely, If the examining asbestos in drlnklng water m In length besed upon tho recent NTP shortor fiber had been ellmlnated from have not shown a conslstent Eioassay in mule rots? the posltlve intermediate fiber study, relatic iship between asbestos and 3. Is the analytical method levels would have been lowor by a carclnogenic effects. Thtu, EPA could lechnoloRically adequh le to determine factor of about 2.5. conclude that sufficlent evidence in not the level of asbastor fibers >IO pm in While elgnincant efforts have been avallable to demonstrate that asbestos drlnklng water? expended to determlno the potentlal In drlnklng water Is associated wlth 4. The RMCL for nrbentos fibers is human health risks of exposure to organ-specific cancers and an RMCL exceedlnR 10 pm in length in proposed asbestos via drinkinR water, questlons not warranted. As a suboption, EPA based upon the 10-'rlsk level, us stlll rcmaln. Summarizing: could prepare a health advisory based calculated by CAG from enimal Asbestos has carclnogenlc effects upon the dnta from the NTP study but it ingestlon studies which considered the via inhalation exposure In humans. would be In the form of guldance rather assoclatlon between fiber length and Animal studies conslsllng of oral than enforceable standard. The second option conslsls of carclnogeniclty. The RMCL could elso exposure to osbestos were negative be based upon the risk levels derived by except in one experiment In the recently proposing an RMCL for asbestos fibers CAG from cohort sthidiesof populetions reported NTP study (draft report. 1984). exceeding 10 um In length. The basis for this optlon that asbestos hns been occupationdly exposed vie inhalation. Epldemiolo y studies examlnlng Is These risk levels derlved from asbestos In drintlng water have not shown to be a human carcinogen through inhalation exposure and data occupational exposure do not consider found consistent credible correlations fiber size in the anolyais. Which of these between carclnogenlc effects and exlsts which suggests that asbestos may be associated with an Increased risk of risk calculations are more appropriate a sbest os. as the btlals for the RMCL? Evldence exists which shows gastrointestinal cancer through Increased risk of gestrolntestinal cancer occupotionel exposure. The results of 3. Dorium from inhalation of asbestos flbers during the NTP study showed an association in male rats between ingestion of asbestos Barium is a netorally occurring metul occupstlonal exposure. However, found In many types of rock. questions have been raised as to flbers greater than 10 pm In length and gastrointestinal tumors that may be Llmestones, sandstones, and soils in the whether the gastrolntestlnal cancer was eastern United Stalea may contain 300- caused by swallowlng inhaled fibers or indlcatlve of carclnogenic effects. In additlon, evldence exlsts to support the 500 ppm barium. Certain Reologic due to other mechanlsrns. formations in Callfornla, Arkansas. EPAs Science Advlsory Board (SAB) assoclatlon between asbestos fiber length and carcinogenic effects: Missourl, and Illlnois are known to examined the questlon of the contain barium levels about 1,000times carcinogenlc potentlal of Ingested Inhalation exposure to medium and long ( >IOum) fibers have been shown to higher than those found in other portions asbestos In 1984 but without access to of the United States. Areas associated the latesl NTP report of benign result in mesotheliomas In rats while nonfibrous pertlculates have not been with deposits of coal, petroleum. natural adenomateous polyps in male rats. They gas. oil concluded: shown to cause tumors. Asbestos would shale, black shale, and peat may be consldered to have equivocal also contain hlgh levels of barium. Clven the posltlve slgnal seen In some evidence of carcinogenicity In drinking Prlnclpal areas where high levels of epldemlologlc studles. plus well-documented water (Reguhlory Category 11) and the barium have been found in drinking evldence for the assoclatlon between water include parts of Iowa, Illinois. asbestos fiber lnhaiatlon and lung cancer. It RMCL would be proposed at the IO-' Is hard for the Commlttee to feel comfortable risk levels (Le.. 7.1~10'fibers/liter). Kentucky. and Georgia. In dlsmlsslng the posslblllty of an Increased Comment would then be requested on The envlronmental release of barium risk of gastrolntestlnal cancer In humans whether there Is on avallable analytical Is also assoclated with oil and gas exposed to asbestos fibem from drlnklng method for asbestos. If so. an MCL for drilling muds, coal fired power plants. water. However, the Commlttee consensus Is long fibers would be proposed. If It le fillers for automotive paints and that current peer-revlewed evldence for determlned that an analytical method specialty compounds used in bricks. humans and anlmals does not support the was not avallable, a treatment tiles, and Jet fuels. view that asbestos Ingested in water causes regulation would be proposed. Analytical Method#. Analytical organ-speclnc cancers. EPA Is proposing an RMCL for methods available for analyzing barium The ShB reexamined the Issue in asbestos (Option #2) at the present In drlnklng water include the flame 1885, considering whether the increased tlme and le sollclling public comment on alomlc absorption, furnace atomlc lncldence of benlgn polyps reported In the arbestos Issue. An RMCL Is being absorptlon and lnductlvely coupled

SM4999 OO63(03)(l2-NOV-85-t 5:2t: IO) F4701 rev. 614-85 48964 Federal Raglster / Vol. 60, No. 219 / Wedneeday, November 13, 1985 / Proposed Rules plasma emission rpectrometry Columbia, MO,Unlrersity of Missouri reason and because of the widespread techniques. Press, pp. llb1841. Exposure lo 100 mg/l occurrence of barium In drinking water, Humon Ex 08um. Barlum la present in barium in drlnklng water for 1 lo le EPA Is proposing to continue to regulate ambient air Prom combustion of diesel months produced hypertenslnogenic and barium. Factoring in data on human fuel, aviation fuel. coal, as well as cardiotoxic effect8in rets. A provlslonal exposure (0.7 mg/day via the diet and 0 mlning reflnlng and manufacturin . Dnla AADI of 1.8 mg/l was calculated from a mg/day via air), the RMCL Is being collected by EPA show the mean feve1 of LOAEL of 100 mg/l barium (6.1 mg/kg/ proposed as 1.6 mg/l. This value is five- barium in air ranges from 0.00160.8~ day) with an uncertainty factor of 100. fold lower than the barium level (7.3 me/ pR/ml. Median and mean values for and assuming consumption of 2 liters of I) which Brenniman, el el. (1981)found individual sites have generally been water per day. An uncertainty factor of to roduce no effects on blood pressure shown to bo below 0.4 pg/ma, which 100 was a plied, Instead of the in R umans. It is also lower than the would result In an adult male having an traditiona PlooO-fold uncertalnty factor chronic SNARL of 4.7 mg/l derived by rpproximate respiratory intake of 0.03- used with a LOAEL, based upon the NAS (ieaz). Thus, this RCML of 1.6 mg/I 22 pg/day. The International minimized exposure of the rats to trace contains a several-fold safety factor and Commission on Radiological Protection molal8 (I.e., calclum) in the experiment. should be sufficiently protective against (ICRP) (18741 eslir..ates respiratory This lack of calclum could contribute to adverse effects. intake to be 0.08-28 pglday. the hypertenslnogenlc effects observed. Questions for Comment: Little data are available on the level Tho current MCL for barium, under of barium in the U.8. food rupply. It has 1. Is it appropriate to base the RMCL the National Interim Prima Drinkin on the hypertensinogenic and been reported that nuts contain high Water Regulations, is 1 mgr. This vafue cardiotoxic potential of barium in levels of barium, with loo0 ppm in was based upon the threshold limit animals? pecans and up to 10,oOO ppm in brazil 0.6 value (TLV) of mg/maair, assuming 2. Should the epldemlologlcal study by nuts. Studies on four individuair 78 that percent of the barium inhaled is (1901) be used for indicated the dietary intake of barium absorbed into the blood stream and that Brenniman, et el. ranged from 44&1800 pg/day. derivation of the RMCL without The 80 percent is absorbed via the additional safety factors? "average" value of 900 pg/day gastrointestinal tract. reportedly includes Intake from In 1982, the NAS (Drinking Water and 3. Should the chronic SNARL value for barium of 4.7 mg/l be used as the beverages. The ICRP reports an Health, 1982. Vol. IV) derived a revised "rverage" daily dietary intake of 760 chronic suggested no-adverse-reeponee RMCL? pglday for an adult male from food and level (SNARL) for barium of 4.7 mg/i. 4. Cadmium fluids. of which 80 pglday comes from This value was derived based upon the Cadmium is found in very low drinking water. Based on these data, the TLV of 0.6 mg/m* air and aeeuming a 20 diet contributes approximately e70 pg percent gastrointestinal abeorption rate concentrations (usually >1 ppm) in barium to the adult human Intake each for barium in the adult human. However, most rocks, as well ae In coal and day. animal studies indicate that young rats petroleum and often in combination Compliance monitoring indicates that absorb up to 86 percent of an with zinc. Geologic deposits of cadmium 43 community water supplies in the adminietered oral dose of barium can eerve as eources to ground water United States contain more than 1 mg/l compared to 7 percent absorption in and surface water, eepecially when in of barium (the current interim standard). adult rats. Thue, 4.7 mg/l does not contact with soft, acidic waters. Data on 132 ground water aystems appear to be applicable to the general Cadmium uses include electroplating. assembled between 1-1980 ahow that population which would include young nickel-cadmium batteries. paint and approximately 14 percent of thoee children who would also have an pigmente. and plastic etabilizere. It le syetems contained levels of barium enhanced uptake efficiency over adults. introduced into the environment from greater than 250 )r /1 and 1-2 percent An epidemiolo ical study of mining and smelting operations and were over loo0 p31: data from rurface communities in lainois demonstrated industrial operations, including water eystems indicated that 14-15 that male and female adults living in the electroplating, reprocessing cadmium percent of 28 systems contained levels high-baidum (7.3 mg/l drinking water) scrap and incineration of cadmium- of barium greater than 250 pq/l but no community for more than ten yearn did containing plastics. The remainlng levels above the 500 pg/l level were not manifest signiflcant dtfferences in cadmium emiseions are from fossil fuel found. mean systolic/diastolic blood pressures use, fertilizer application and sewage Health Effects. Acute exposure to (Brenniman, G.R., et el., 1981. High sludge disposal. Cadmium may enter barium in animals and humans resulte in Barlum Levels In Public Drinking Water drinking water as a result of corrosion of a variety of cardiac, gaetrointeetinal and ar,d its Association with Elevated Blood galvanized pipe. Landflll leachates are neuromuscular effects. Inadequate data Pressure. Arch. Environ. Health 3628- also an important source of cadmium in were available to calculate shortterm 32). However, several factom in thls the environment. aeeeesments for barlum. study have been questioned, such as Analytical Methods. Analytical The role of waterborne barium In the confounding varla bles, uncontrolled methods available for analyzing etiology of experimental and human parameters and data inconsistencies. cadmium in drinking .taler include the "eeeential" hypertension remains a The lARC have not evaluated barium flame atomic absorption, furnace atomic matter of controverey and conjecture. A for possible carcinogenic effects. Barium absorption and inductively coupled provisional AADI waa calculated based has been classlfied in EPA'8 Group D, plasma atomic emission spectometry upon an experimental study showing according to DA's Proposed Cuidellnes techniques. chronic exposure to barium resulting in for Carcinogen Risk Assessment, based Human Exposum. Cadmium is hypertension in rats (Perry, H.M., et el. upon inadequate data from animal Introduced into the atmosphere by both 1983. Cardiovascular Effects of Chronic studies. natural and anthropogenic means. Barium Ingestion. In: Hemphill, D.D., ed. Barlum exposure has been aesociated Higher levels are found In areas where F'roceedlngs of the 17th Annual with h ertension and cardlotoxlclty in non-ferrous metal mining, smelting and Conference on Trace Substances in animapand a provisional AADI of 1.8 refining occur. .41so, cadmium levels in Environmental Health, Vol17, mg/l has been detennlned. For thls air are hlgher in urban than in rural

SMIPPP wO3nIZ-NOV-85- t5:Zl:lZ) F47m rev. 8-14-85 - Federal Register / Vol. 60, No. 219 / Wednesday, November 13, 1985 / Proposed Rules 46965 areas. Clgarettes contain high levels of An animal study (Kotsonis and carcinogenicity in animals and cadmium, and thus tobarco smokers Klaasen, 1878. The Relationship of inadequate evidence lor activity in have an Increased respiratory intake of Metallothionein to then Toxicity of short-term tests. Tlie IARC clHssificetion cadmium. Dota collected by EPA show Cadmium after prolonged Oral is based on exposure to cedmlum via mean levels of cadmium in air to Administrelion lo Rats. Toxlcol. Appl. inhalation. However. no evidence hen typically range from 0.000so.01 &ma. Pharm. 48338-54) was used for the been found llnklng lngesticn of cadmium Using 0.M pg/m' as a typical. high value derivation of 10-day assessments for with carcinogenicity in anlmels or and 20 m'/day as the ventilation rate. children and adults. From a N0AP.L of humens. Cadmium has been clessiiicd in the respiratory intake for the adult male 0.08 mg/kg/day based on proteinuria EPA's Group B1, according to EPA'a would be up to 0.20 pg/day. followlng up to 24 weeks of cadium Proposed Culdellnes for Carclnogcn Cadmium is present in low levels in feeding in rats. with an uncertainty Risk Asaessment. bgsed upon evidence most foods. The FDA examined 481 factor of 1.ooO (an additional uncertainly of carcinogenicity in humans through samples of 12 raw agricultural factor of 10 was used due lo tho number inhalation exposure. Itowever. since commodities and found cadmium to be of animals (6 rats] per dose group], and cadmium has not been shown lo be present at or above trace (0.02 ppm) assuming consumption of 1 liter (10 kg/ carcinogenic through Ingention quantities in at least one sample of each child) or 2 liters (70 kgladult) of water exposure, the compound will be product. Soybeans, peanuts, beans, per day, 10-day assessments for a 10 kg/ regulated based upon chronic toxicity wheat, and lettuce were found to have a child and a 70 kg/adult of 8 pg/l and 28 data. high frequency of samples with elevatad pg/l, respeclivcly were calculated. The NAS (Drinking Walcr and levels (>0.15 ppm). Shellfish are noted Those values would be very Health. 1982. Vol. IV) estimcrted 8 for high cadmium levels, reportedly conservative because of the extended SNARL for cadmium of 0.005 mR/I biisrtl ranging from 0.7-7.8 ppm. The FDA has length of the lest (24 weeks). These upon the same study whlch wiis used to estimated that daily dietary cadmium values would be considered protertive calculate the 10-day anscnnmant velum intake for the adult male Is 27.2 p~ of the child and adult for a one-day (Kotsonis and Klaesscn. 1878. The (exchding beverages). Grains and exposure. Relationship of Metallothionein to the , cereals, potatoes, meat. fish and poultry A provisional AADl was calculated Toxicity of Cadmium rrfter Prolonged were identined as major food categories using renal dynfunction as an endpoint. Oral Administration to Rats. 'I'oxicol. contrlbullng to cadmium Intake. The critical [threshold) concentration of Appl. Pharmacol. 46:38-54). Complltrnce monitoring indicates that cadmium in the renal cortex associated The current MCL for cadmium, under there are currently 25 public water with renal dysfunction has been the National Interim Primary Drinking supplies with reported levels of calculated to range from 50 pg/g lo 300 Water Regulations. is 0.010 mg/l. This cadmium above 10 pgll. the current pg/& A value of 200 pg/g (Friberg. L., et level was based upon H cadmium level standard. Data on 707 ground water el. 1974. Cadmium in the Environment. of 200 ppm in the renal cortex supplies obtained in federal aurveys 2nd ed. Boca Raton, Florida: CRC Ress association with proteinuria. with 5 conducted between 1089-leBo show that Inc.; Kjellstrom, et el. 1864. Conceptual percent gastrointestinal absorption, about 27 percent have levels above 2 Problems in Establishing the Critical rapid excretion of 10 percent of the pg/l; then mean of the positives was Concentration of Cadmium in Human absorbed dose and 0.05 percent daily about 3 pg/L In the same federal survey, Kidney Cortex. Env. Res. 33:284-295) has excretion of the total body burden. It 18.7 percent of 117 surface water been selected as the basis of the NOAEL was estimated that it would take about supplies had levels above 2.0 pg/l: the in the calculation of the provisional SO(WOO pg/day to ca~eproteinuria and mean of the positives was 3.2 pg/l. None AADI. This value is probably the most with assumed diet of 75 pg/day, a were found to exceed 10 pg/l. widely accepted estimate of the critical drinking water level of 0.010 mg/l would Health Effects. Acute and chronic concentration for renal dysfunction. provide a four-fold safety factor. The exposure to cadmiurn in animals and Several models have been proposed to provisional AADl was also determined humans results in renal dysfunction, estimate the dally intake of cadmiurn based upon renal dysfunction as an hypertension. anemia and a!tered liver required to rcclch the critical endpoint, but newer data were used to microsomal activity. The kidney is concentration in the renal cortex. Using determine the critical concentration in considered to be the critical target organ a conservative model (Friberg. L., et el., the renal cortex and the daily intake of in humans chronically exposed to 1874) which assumes 4.5 percent cadmium required to reech this criticel cadmium by Ingestion, The early clinical absorption of the daily oral dose and concentration. signs of renal injury include proteinuria, 0.01 percent excretion of the total body The WHO Ruidelinc! for drinkin# glucosuria and aminoaciduria. burden per day, a daily intake Of 0.352 water Is 0.005 mg/l. This value warn A human study (Lauwerys, 1978. mg/day cadmium will be used as the derived based upon the provisional. Cadmium in Man. In: Webb. ed. The LOAEL for renal effects in humans. A tolerable weekly intake of 0.4-0.5 Chemistry, Biochemistry and Biology of provisional AADI of 0.018 mg/l ha8 been person. established in 1972 by the joint Cadmium. Elsevier/North Holland calculated using an uncertainty factor of FAO/WHO Expert Commitlee on Food Biomedical Press, pp. 43-53) was 10 and consumption of 2 litera of water Additlves. The WHO determined that II selected for the derivation of short-term per day. guideline value of 0.005 mg/l was assessments for children and adults. Cadmium and cadmium compounds suitable based upon the fact that at this From a NOAEL of 0.043 mg/kg/day have been shown to induce sarcomas at concentration about one-quarter of the based on the emetic effects following injection sites in animals when total cadmium absorbed might be acute exposure in adult humans, with an administered parenterally and cadmium derived from water. EPA's ambient uncertainty factor of 10. and assuming chloride given by aerosol for 18 months water quality criteria for human health consumption of 1 liter (10 kg child) or 2 can produce lung tumors in rats. The (U.S.EPA. 1W.Ambient Water Quality liters (70 kg adult) of water per day, 1- IARC have classified cadmium and Crtterle for Cadmium. EPA 440/540- day assessments for a 10 kg child and 70 certain cadmium compounds in GMU~ 025) is 0.010 mg/l considering ingestion kg adult of 43 pg/I and 160 pg/l were 28; limited evidence for carcinogenicity of water and contaminated aquatic detennlned, respectlvely. in humans, sufficient evidence for organisms. This value was based upon

F4701 rev. 614-85 40986 Federal Reglrter I Vol. 50, No. 218 1 Wednesday, November 13, 1885 1 Proposed Rules an analysis whlch concluded that water operetlons may result in releases of There are no suitable data available constitutes only a relatlvely minor chromium lo the atmosphere, for calculatlng one-day assessment portlon of the total cadmium intake and Analytical Methods. Analytical values for chromlum 111 or chromlum VI. thus the exlsting drlnklng water methods available for analyzing However, the ten-day assessment for rtandard of 0.010 mg/l was determined chromium In drinklng water Include the chromlum VI of 1.4 mg/l for the 10 kg to provldo ample protection for human flame atomic absorption, furnace atomic child and 6.0 for the 70 kg adult will be health. absorption and inductively coupled protective for one-day exposures. Because of cedmlum's potential plasma atomlc absorptlon emlsslon An anlmal study [Gross and Heller. adverse health effects and widespread spectrometry techniques. occurrence In raw waters, EPA Is 1648. Chromates in Anlmal Nutritlon. J. Humon Exp08ure. Data from EPA for Ind. Hyg. Toxicol. 28:52-68) was selected proposing to contlnue to regulate It In the years 1977 to 1981 show that the NPDWR. The NAS and the WHO to serve as the basis for calculatlons of amblent alr at most stations has mean the Chromium VI 10-day aesessment for have delermlned guldellnes Of 0.005 mg/ values below 0.3 pg/ma(24-hour I cadmium. A provleional AADl of 0.016 the 10 kg child and 70 kg adult. From a averages) and medlum values below 0.2 NOAEL of 14.4 mg/kg/day based on no- mg/l has been calculated. An RMCL of pg/ma. Twenty-four hour average 0.005 mg/l Is proposed based upon the effects In rats following a Wday concentrations In the U.S. for total exposure, with an uncertainty factor of NAS and WHO guidelines whlch would chromium generally range between 0.005 result In a theoretical aliocatlon to 100. and assuming consumptlon of 1 Mer and 0.157 pg/m? Maximum annual (10 kg child) or 2 liters (70 kg adult) of drinking wbter of tlpproximately 25 average amblent (total) chromlum levels porcenl of the ADI. water per day, ten-day assessments for within 20 kllometers of emlsslon sources the chlid and adult of 1.4 mg/l and 5.0 Quesllons for Comment: have been predicted to range from 0.01 1. it appropriate to use a value of mg/l were calculated. Is to 13.5 pg/m? u)o pg/R as the critical concentrallon of Suitable data were not avmilable for cadmlum In the human renal cortex? Nearly all foods contain some calculallng chromium 111 10-day chromlum. ranglng from lo 690 pg/kg. 2. Is the model used lo estimate the 20 assessments for the child and the adult. daily Intake of ctrdmlum required to The largest sources are meals, mollusks, crustaceans, vegetables and unrefined A provisional AADl for chromium reach the critical concentretlons in the (through the oral route of exposure) was renal cortex based upon reasonable sugar. Dletary intake In humans haa been estimated to range from 5 to 500 determined on the basis of the effects of assumptione? Cr VI and a eeparate AADl was not 3. In the drinking water criteria pg/day, with a typical value of approximately 100 pg/clay. determined for Cr 111 for the following document on cadmlum, an alternate reasons: etudy Is cited (Perry, et ai., 18nb, 1879) Compliance monitoring data indicate for the derivation of the RMCL that 17 ground water and one surface 1. Cr 111 and Cr VI are in dynamic Comments are requested on the use of water supply have provlded drinking equilibrium, the degree of oxidation In this study In the posrlble derlvatlon of water wlth levels greater than 50 pg/l. an aqueous medium dependlng on the RMCL Twelve of the ground water supplies are factors such as pH. dissolved oxygen, or 4. Is the use of 25 percent drinking small systems serving fewer than 500 presence of reducing agents. In ambient water contribution reasonable In people: only 3 serve more than 10,0oo water (as opposed to sediments) there is determining the RMCL? people and none serve more than 75,000 slow oxldation of Cr 111 to Cr VI. The people. However, the one surface water rate of this oxidation is accelerated by 5. Chromlum eupply serves more than 100.ooO people. the addition of an oxidizing agent Chromlum Is a naturally occurring In three national surveys conducted (MnOl). It has been shown that water metal that in drinklng water forms between 1Wand 1980, chromium was treatment Involving chlorination will compounds wlth valences of +3 and found to be present at levels above 5 effectively transform Cr 111 to Cr VI. The +6, with the trivalent state belng the pg/l In 77 of 795 ground water supplies normal presence of resldual oxldlzing more common. The average chromium sampled (9.m).The mean of the posltlve capaclty in treated water throughout the content of the earth's crust has been values was 16 pg/L wlth values ranging water distribution system will assure estimated to be 40 ppm. with a range of up to 48 pg/l. In surface water supplies, maintenance of dissolved chromium in 10-200 ppm for most geologic materials. chromium was found at levels above 6 the oxidlzed state; therefore, if Chromium levels of 1.000-12.800 ppm pg/l in 24 of 142 systems sampled chromium is present. drinklng water at heve been reported for certaln ultramific (16.9%). The mean of the positives was the point of consumption [Le., the tap) is rocka that are high In Iron and 10 pg/k none of the surface water likely to contain substantial amounts of msgneslum and low in sllica. The only supplies had values above i%pg/I. Cr VI. commercial chromium ore Is chromite, Health Effects.Chromium 111 (Cr Ill) 2. Cr VI is more toxic than Cr Ill. since which occurs In small deposits in and chromium VI (Cr VI) have greatly only the hexavalent species readlly Washington, Oregon. California, differing toxiclty characledstlcs. crosses cell membranes. The Montana, Wyomlng, Tex6a. Chromium 111 is a nutrltionally essential nonmulagenlcity of Cr 111, as contrasted Pennsylvanla. Maryland, North Jement; the NAS (Drinking Water and wlth the mutagenicity of Cr VI, can be Carolina, and Georgia. Heolth, 1980. Vol. Ill) have estimated an directly attributed to this fact, even Although chromium is not currently adequate and safe intake level for adults though Cr Ill reacts with DNA In the mined In the U.S., wastes from old of 0.05 to 0.20 mglday via the diet. cells. An AADl based on Cr VI, mining operatlons may enter surface Chromlum VI is much more toxic than therefore, will be conservative with and ground water through runoff and Cr Ill and has been shown to produce respect to any Cr Ill which might be leachhg. Chromats wastes from plating herand kidney damage, internal present in water. operationu may also be a qource of hemorrhage, and respiratory disorders. 3. Even though orally ingested Cr VI is vroter contamination. Fossil fuel Also, subchronlc and chronic exposure reduced in part lo Cr 111 during passage combustlon, waste inclneratlon, cement to Cr VI in the form of chromlo acld can through the rtomach, reduction is plant emissions, chrome platlng and cause dermstills and ulceration of the Incomplete, and there is greeter other metalluqkal and chwnlcal rkin. absorption and greater tissue sM4999 OObqOINI2-NOV-I5-~I5:22:56) F47M rev. 6-14-65 Federal Regislor 1 Vol. 60, No. 218 1 Wedneeday, November 13, lQ85 / Proposed Rules 46967 accumulation of chromium following effects in animals and humans by Copper is found in certain foods ingestion of Cr VI than Cr 111. Ingestion. EPA is proposing to continue including shellfish (especially oysters) A study in which rats were supplied regulation of this contaminant because and organ meats (lamb. beef. or swine drinking water containing up to 25 mR/I of the potential adverse health effects liver). Nuts. dried legumes, dried vine Cr VI for one year was used to calculate and its widespread occurrence. An and stone fruits and cocoa are a provisional AADI (MacKenzie, R.D., et RMCL of 0.12 mg/l is proposed for total particularly rich in copper. The copper chromium (Cr 111 and Cr in drtnking al. 1958. Chronlc toxicity studies. [I. VI) ' content of these items can range from IO Hexavalent and Trivalent Chromium water, based upon a provlsiorial AADI pg/g to as high as 400 pgIg. Dairy Administered in Drinking Water to Rats. of 0.17 mg/l with data on human products, white sugar. and honey rarely AMA Arch. Ind. Health 18:232-234). This exposure factored in (0.10 mg/day vi0 contain more than 0.5 pg copper/g. The rludy resulted in a NOAEL of 2.41 mg/ the diet and 0 mg/day via air). nonleafy vegetabler and most frcsh kglday. Using this NOAEL, an Question for Comment: fruits and refined cP-eals generally uncertainty factor of Mx) based upon an 1. Should the RMCL calculatrd for contain up to 2 pg/g. Cheese. milk, beef. animal study in which the rats were chromium be based on total chromium mutton. while and brown bread and exposed to Cr VI for only 40 percent of a (Cr I11 and Cr VI). or should separate many breakfast cereals (unless they are normal span, and consumption of 2 liters RMCLs for the two valence states be fortified) are relatively poor sources of of water per day, a provisional AADI of calculated? Are the available analytical copper, Le., they have less than 50 pg 0.17 mg/l was determined. methods sensitive enough to copper/100 kcol. The refining of cereals The IARC have classified chromium differentiate readily between the two for human consumption results in and certaln chromium compounds in valence states? eignifictlnt losees of copper, although Group 1 (chromium VI); sufficient 6. Copper this loss is not so severe as it is for iron. manganese and zinc. evidence for carcinogenicity in humans Copper Is ubiquitous in the earth's and animals. The IARC classification is A daily copper intake of 2 mg is cmst. occurring commonly as sulfides considered to be adequate for health based on inhaled chromium VI. and oxides and occaeionally as metallic Chromium has been classified in EPA's copper. Weathering and dissolution of and normal copper metrrbolism. The Group A. according lo EPA's Proposed these natural copper minerals results in normal daily adult intake of copper from Guidelines for Carcinogen Risk background levels of copper in natural food in the U.S. is reported to range from 2.0 to 4.0 Assessment, based upon positive surface waters at concentrations mg per day. The reported inhalation data for chromium VI in generally below 20 pg/l. The principal average intake of copper in young humans and animals. However, since sources in drinking water include children is 1.5 mg per day: the minimum chromium has not been shown to be corrosion of braes and copper pipe by dietary requirement is 0.10 pg/kg of carcinogenic through ingestion acldic waters. and other sources include body weight per day. exposure, the compound will be use of copper salts an aquatic algacides, Water can be 9 significant source of regulated based upon chronic toxicity industrial effluente, atmospheric fallout copper intake depending upon the data. and eewage treatment plant effluents. geographical location, the character of The current MCL for total chromium, The major industrial sources include the water [Le., hardness. pH. alkalinity), under the Plationel Interim Prtmary smelting and refinlng industriee, copper the temperature of the water and the Drinking Water Regulalione. la 0.05 wire mills, coal burning industries and presence of copper-containing pipes. > mg/l. This value was based upon an iron and steel producing industries. In 1987. the U.S. Department of analysis which concluded that 0.05 mg/l Copper may enter natural water either Interior published the results of a five- chromium incorporates a reasonable directly from these sources or by year etudy of 380 finished drinking factor of eafety to avoid any hazard to atmospheric fallout of air pollutanta water systems. Analysis of results human health. produced by these induatries. showed levels of copper to range from 1 The WHO guideline for drinking Anal tical Methods. Analytical to 1.080 pg/L with a mean of 43 pg/I. In water is 0.05 mg/l for chromium, as Cr methodYs available for analyzing copper 1970, the U.S. Department of Health. VI and also total chromium. This value in drinking water include the flame Education and Welfare reported the was based upon the 1870 European atomic absorption, furnace atomic average concentration of copper in standards for drinking water. EPA's absorption and inductively coupled drinking water supplies to be 134 pg/l. ambient water quallty criteria for human plasma atomic emission spectrometry with a maximum concentretion of 8.350 health (U.S. EPA. 1980. Amblent Water techniques. pg/l. Results of a survey of 83 water Quality Criteria for Chromium. EPA 440/ Human Exposure. The principal supplies bv EPA Region V showed 543-0351considering Ingestion of water source of elevated copper levels in air is copper to range from c 5.0 to 200 pg/l in and contaminated aquatic organiems for copper dust generated by copper- finished drinking water. Cr 111 and Cr VI are 170 mg/l and 0.050 processing operations. Coal-burning Hibher copper levels have been mg/L respectively. These values have power plants are another eource of observed in tiesue eanrplcs of residents been updated (February 1964.49 FR copper emissione and tobacco smoke is of cities with soft water. This might be 4551) and the propoeed revised values a possible source. due lo corrosion of copper pipes and are 58 and 0.050 mg/l for Cr 111 and Cr In 1968, a National Air Sampling fittings, thereby increasing the intake of VI, respectively. These values are baaed Network survey showed that the soluble copper. Another explanation upon dose dependent reductions in airborne copper concentrations were may lie in the abillty of calcium or organ weights of the liver and spleen for 0.01 and 0.267 pg/m' in rural and urban magnesium ions in hard water to chromium I11 and the obeervation that communities, rcspectlvely. Even near suppress the intestinal absorption of the standard appears. through past copper smelters, where high levels (I to coppcr. experience, tu be satiefactorily 2 pg/m') ere reached, the dose of metal Health Effects. Copper has toxic protective against chromium VI toxicity that would be acquired through effects at hlgh dose levels and is an in humans. inhalation of ambient air would essential element at lower levels. Toxic Chromium exposure at high levelo has comprise only about 1 percent of the effects resulting from acute exposure to been shown lo resull in chronic toxic total normal daily intake. copper in laboratory animals and

SM4999 a)67(O(~t2-NOV-85-tJ:22:SS) F47a rev. &14-85 - -46986 Federal Register / Vol. 60, No. 219 / Wednesday, November 13, 1985 / Proposed Rules humans include gastrointestinal recesslve lethal mutatlons in D. media, the atmosphere is the major disturbances. hemolytic anemia, rend melanogaster at high concentrations. initial recipient of lead emisslons. The damage, herdamage and glucose-li. Equivocal results have been obtained maln nource of lead in drtnklng water is phosphate dehydrogenase inh1bl:ion. from carcinogenicity studies. leaching from :ead piplng and services Limited data are available on the Administration of copper compounds to and lead solders. Airborne lead from chronic toxicity of copper. Efficient mice by subcutaneous injection has gasoline combustlon may be one of the homeostetlc mechanisms generally been reported 10 induce tumor major contrlbutors to total lead in protect mammals from the adverse formatlon. Orally administered copper drinking water. effects of dietary copper excess. In compounds were not found to Increase Analytical Methods. Analytical humans. individuals with Wllson's tumor incidence in several studies. The methods available for analyzing lead in disease are at additional risk from the IARC have not evaluated the drinking water include flame atomic loxlc effects of copper. Wilson's disease carcinogenic potential of copper. Copper absorption, furnace atomic absorption. le an inborn error of copper metabolism has been classified in EPAs Group D, inductively coupled plasma atomic in which copper accumulates In the according to WASProposed Guidelines emisslon spectrometry techniques, X-ray liver, brain and kldney, resulting in for Carcinogen Risk Assessment, based fluorescence, colorimetric analyses and hemolytic anemia, neurological upon inadequate data in humans and electrochemical techniques such as abnormalities and corned opacities. In animals. stripping voltometry. addllion. individuals with glucose6 WASambient water quality criteris Human Exposure. Human populations phosphate dehydrogenase (COPD) for copper (U.S. EPA. 1980. Ambient In the United States are exposed to lead deflclency are likely to be at Increased Water Quallty Criteria for Copper. EPA in air, food, water and dust. In rural risk to the toxic effects of copper. 440/6-80-036) is 1 mg/l, based upon areas, Americana not occupationally Copper is regarded as an essential taste and odor considerations. Copper le exposed lo lead are estimated to element in mammalian nutrition because included In the National Secondary consume W pg Pb/day. This level of it is requlred in many enzymatic Drinking Water Regulations (EPA, exposure is referred to as the baseline reactions. Copper deficiency can result National Secondary Drinking Water exposure for the American population in decreased iron absorption and iron Regulations, 1979) as a secondary because it is unavoidable except by deficiency, and may also lead to standard of 1.0 mg/l based upon taste drastic change In lifestyle or by reproductive abnormalities. The NAS and odor. The WHO has not proposed a regulation of lead in foods or ambient (Drinking Water and Health, 1980. Vol. guldellne for copper based upon health 111) has recommended an adequate and air. Forty-four percent of the baseline effects: however they have proposed a consumption of lead by children is safe intake level of mg/day per. 1 mg/l. 2-3 co guideline value of based upon estimated to result from consumption of One-day assessments of 1.3 mgjfor the ability of copper to stain laundry the adult and the child were detennlned 0.1 g of dust per day. Ninety percent of and plumbing fixtures at concentrations this dust lead is of atmospheric origin based upon a LOAEL of 5.3 mg/day above 1 mg/l. based upon human clinical case studies (US. EPA, 1984, Air Quality Criteria for Copper exposure at high levels may Lead. EPA (Chuttani, H.R.,et el. 1985. Acute resul t in gastrointestinal disturbances 6008-23-02BB). Copper Sulphate Poisoning. Am. J. Med. and other ncute toxic effects. For this Leaded gasoline combustion in 39:849) in which 5.3 mg was the lowest reason and because occurrence la vehicles accounts for about 90 percent oral dose at which gastro-intestinal widespread. EPA is proposing an RMCL of the total anthropogenic input of lead effects were seen. An uncertainly factor for copper. The RMCL will be based to the atmosphere. Atmospheric lead of two was applied for the following upon acute toxicity effects and a RMCL concentrations can renge from 0.000078 reasons: (1) The effect noted was local of 1.3 mg/l is proposed. Data on human pg/m* in rpmote areas to IO pg/ma near gastrointestinal irritation and was not exposure were not factored in the polnt rnurces: EPA data show the permanent, (2) 5.3 mg was the lowest provisional AADI because the average annual values in most areas to value determined in the literature based calculations were baaed upon acute be below 1.0 pg/m'. The EPA has upon a number of studies and thus is effects. estimated respiratory intake of lead to very conservetlve number, (3) copper Is Questions for Comment: be about 1 pg/day for the adult and 0.5 an essential element and the application 1. It there sufficient health effects pg/day for a 2 year old child (U.S. EPA, of a larger uncertainty factor would Information upon which to base an 1985, Occurrence of Lead in Drinking bring the level below that considered RMCL, or should a health advisory be Water. Food, Air; U.S. EPA. 1984 Air necessary for human nutrition and, (4) developed instead? Quality Criteria for Lead. EPA-BOO/& copper absorption is controlled by a 2. Is it appropriate to base the RMCL 83-028B). homeostatic mechanism and the for copper uoon acute, short-term The route by which adult8 and older compound does not tend to accumulate effects? children In the baseline population of in the body. Tenday values were not the U.S. receive the largest proportion of calculated due to inadequate data. 7. Lead lead intake is through foods. A provisional AADI was detennlned Lead (Pb] is a relatively rare metal in Atmospheric lead may be added !a rood for copper baaed upon the compound's the earth'e crust, ranklng 34th among the crops in the field or pasture, during the acute toxicity effects, since these are the elements In crustal abundance with transportation to the market, during effects of concern from exposure to average concentrations of 16 ppm in the processing, and durlng kitchen copper. The same LOAEL and contlnental United States. preparation. Metalllc lead, mainly from uncertainty factor used to derive the 1- About 65 percent of the lead produced solder, may be added during procee~ing day assessments were used to is used for the manufacture of storage and packaging. Other sources of lead, as determine a provisional AADI,resulting batteries: approximately 10 percent is yet undetermined, increase the lead in value of 1.3 mg/l. used for gasoline additives, the second content of food between the field and Copper compoundr have generally largest use. The remalnder Is used for dinner table. American children, adult provided negatlve results in microbial plgments, ammunition, solder, plumbing, females and adult males are estimated mutation assays. Copper sulfate was cable coverings, ceulklng and bearings, to consume 19,2S, and 38 pg Pb/day, observed to Increase the frequency of Atthou& lead can be released to all respectively, in milk and nonbeverage

I74701 rev. 6-14-85 - Federal Register 1 Vol. 50, No. 219 I Wednesday, November 13, 1985 1 Aopoeed Rules 46869 11------___.-- - foods, plus an additional 7.11. and 19 pg quantified (at lev& above 5 pg/l) in 9oA Inorganic Lead. 1. Biochemical and Pb/day, respectively. in water and other out of 1.200 (75.5%)of ground wnter Haematological Responses. Int Arch. beverabes. The added exposure from supplies sampled. The mean of the Occup. Environ. Health. 35:l-18). and living in an urban environment is about positive values was approximately 26 other signs of impaired heme synthesis 28 pg/day for adults, 91 pR/day for pg/I. with a range of 5-3~0pg/1. In evident el still lower PbB levels. All of children and 38.2 pg/dsy for the 8- surface water supplier. lead was these eff.?cts point toward a gcnmitizcd month old infant (U.S.EPA. 1985. observed at levels of about 5 pg/l In 205 impairment of normal physiological OccurrenceOf Lead in DrinkingWater. out of 273 (70.276) supplies na npled. The functioning across severa aifferent Food and Air: US. EPA. 1984. Air mean of the positive values was organ systems. which becomes et ident Quality Critetia for Lead). as adult PbB levels exceed 30-40 la/tli. Lead enters drinking water primarily approximately 24 &I, with a range of SI84 pg/L The above data include the Evldence for impairej heme synthesis as a result of corrosion of plumbing. effects in blood occur at even Iiiwer PId parficularly in areas having Rural Water Survey (RWS) for which the validity of the lead data have been levels in adults. plumbosolvent. Le.. soft. acidic New research findings demonstrating (pH<6.5) weters. Data from federal questioned. Excluding the RWS. the valuer "re: a rclationship bstween blood lead levels monitoring surveys show that lead was and increases in blood pressure haw -- -_ _--___ appeared in the published literature bvu , PW.n( oovhrr [Harlan. et el. Blood Lead and I. 5 r04 MerndDawwes RnrOI 1985. --___ ------. - Blood Pressure, JAMA.253:53&534: barnd na1u 70 3 0539/1rn) 13 "0" 5-182 "0" Pirkle. et al. 1985. The Relationship Svhr ** U 1 840(1W/119) 14 r0" 5-32 5 rgl1 Between Blood Lead I~velsand Blood ---- Pressure and its Cardiavascula, Risk Implications. Am. journ. Epid. 21:24& Compliance monitoring data for the Latent Plumbism. Am. ;. Clin. 258). A preliminary review of this work Interim Regulations indicate that 66 Pathology). Often associated with indicates a statistically significant public water supplies (59 ground water encephdopathic symptoms at such PbB correlation between blood lead levels and 7 surface water) were reported to levels are severe gastrointestinal and diastolic blood pressure in white exceed the current MCL of 50 pg/l. symptonis and objective signs of effects melee. ages 659,with no threshold Fourteen of the ground water supplies on several other organ systems. Predse apparent in the range of e30 pg/dl. and 3 of the surface water supplies had Ihreshold(s) for occurrence of overt Possible increases in risk of more severe levels above 150 &I. neurological and gastrointestinal signs medical events (etroke. heart attack. HeolfhEffecfs. The health effccts of and symptoms of lead exposure in cases death) associated with lead-induced lead in both humans and animals are of subencephalopathic lead intoxication increases in blood pressure are also generally measured by relating blood remain to be established. but such estimated in one of the recently lead (PbB) levels to adverse effects. effects have been observed in adult lead published analyses (Pirkle. et el. 1985. Numerous studies have been carried out workers at PbB levels as low as 4080 The Relationship Between Blood Lead in which PbB levels of people across the pg/dl. Other types of health effects Levels and Blood Pressure and its United States have been measured, and occur coincident with the above overt Cardiovascular Risk Implications. Am. these levels correlated with adverse neurological and gastrointeetinal lourn. Epid. 21:246-258). effects. This type of measurement has symptoms indicative of marked lead Children represent a sensitive not been done for most other chemicals, intoxication. These range from frmk subpopulation with regard to lead where the effects are described in ttrms peripheral neuropathies to chronic toxicity. As with adults. lead affects of concentration of intake of the nephropathy and anemia. many different organ system and chemical. For the purpose of aeriving an Toward the lowc: rangr of blood lead bicchemical/physiologicalprocess RMCL the PbB levels at which adverse levels associated with overt lead across a wide range of exposure levels. effects occur will be evaluated. and intoxication (Quantification of Effective blood levels for producing these levels will be related to lead levels Toxicological Effects of Lemd in Drinking encephalopathy or death in children are in drinking water. Water. U.S. EPA. 1984. Air Quality lower than for adults. starting at As discussed elsewhere in recent EPA Criteria for Lead). less severe but approximately 80-100 pg/dl. Permanent. assessments of the health effects of lead important signs of impairment in normal severe mental retardation and other (Quantification of Toxicologica~Effects physiological functioning in several marked neurological deficits are among of Lead for Drinking Water. U.S. EPA. organ systems are evident amonq lasting neurological Pequelae typically 1984. Air Guality Criteria for Lead]. the apparently asymptomatic lead-exposed seen in cases of nonfatal childhood lead most serious effects associated with adults. including: (1)Slowed nerve encephalopathy. Other overt markedly elevated blood lead levels are conduction velocities indicative of neurological signs and symptonts of severe neurotoxic effects that include peripheral nerve dysfunction (at PbB subencephalopathic lead intoxication irreversible brain damage. as indexed levels as low as M pg/dl) are evident in children at lower PbB by the occurrence of acute or chronic (Seppalainen. et el. 1975. Subclinical levels (e.8.. peripheral neuropa thiea encophalophatic symptoms: for most Neuropathy at "Safe" Levels of Lead detected in some children at levels as adults such damage typically does not Exposure. Arch. Environ. Health 3&1t10- low as 4(wo pg/dl). Chronic occur until PbB levels exceed 100-120 183): (2) altered testicular function (at nephropathy, indexed hy aminoaciduria. pg/dl (Kehoe, R.A. 1981a. The 40-50 pg/dl) (hncranjan. et el. 1975. is most evident at high exposure levels Metabolism of Lead in Man in Health Reproductive Ability of Workmen over 100 pg/dl. but may also exist at and Disease: the Normal Metabolism of Occupationally Exposed to Lead. Arch. lower PbB levels (e.8.. 7(wo pg/dl). In Lead (The Harben Lectures. 1980). 1.R. Environ. 14th. W.396-401:; and (3) addition, colic and other overt Inst. Pub!ic Health Hy8,24,129-143; reduced hemoglobin roduction (at gastrointestinal symptons clearly occur Smith. P.L.Rathmell. T.K.. Marcll. LE. approximately 50 pgrdl) (Zielhuis, R.L at similar or lower PbB levels in 1938. The Early Diagnosis of Acute and 1975. Dose-Response Relationsh 9s for children, at least down to 60 pg/dl. S-074999 0069(M~t2-NOV-BJ-I5:23~2) - 46970 Federal Reglsler / Vol. SO, 219 / Wednesday, November 1985 / Proposed Rules -- No. 13, Frank anemia is also evident by 70 p8/ evaluation. Prestcnrcd at: Second negatlvely correlated with circulating dl, representing an extreme Internallonel Conference on Prospective levels of the vitamin D hormone. 1,25- manifest atlon of reduced hemoglobln Lead Studies, Aprll. Clnclnnati, OH). dlhydroxyvitamln D, with no evident synthesis observed at PbD levels as low However. the reported threshold, down to 12 pg/dl of PbB as 40 pg/JI, along with other signs of eleclrophysiologlcal effects in thls case (Rosen, J.F. 1884. Metabolic and Cellular marked heme synthesis inhlbltion at were not found to be eigniflcantly Effects of ked: A Culde to Low Level thnt exposure level. All of these effects aesoclated with IQ decrements and in Lead Toxicity In Children. In: Mahaffey. are rencctlve of the widespread marked general, the medical elgnificance of K.R. ed. Dietary and Environmental impuct of lead on the normal many of the electrophysiological Exposure to Lead. In press; Mehaffey, et physiological functioning of many alterations induced by low-level lead el. 1982. Association Between Age. different organ systems; some are exposure remains to be elucidated. Blood Lead Concentration and serum cvldcnl in children at PbD levels as low However, the effects on auditory 1,25-DihydroxycholecalciferolLevels in a9 40 pg/dl. and all are widely accepted brainstern evoked potentials observed Children. Am. 1. Clin. Nutr. 35:1327). This an clearly adverse health effects. tlcross the range of PbB levels of e and effect of lead is of coneiderable hdditionnl studies demonstrate 59 pg/di may be an indication of subtle significance on two wunls: (1) Ailered evidence for further. important health neurologlcnl impairment (Otto, et ul,, levels of 1,25-(OH),-vitornln D not only effects occurring in non-overtly lead 1984). impact calcium homeostasis (affecting intoxicated children at sirclilar or lower Rceearch concerning lead-induced mineral metabolism, calcium as a blood lend levels than those lndlcated effects on heme synthesls also provides second messenger and calcium as a abovc. Among the most important and information of the importance in mediator of cyclic nucleotide controversial of these effects are evaluating what blood lead levele are metaboliem). but also likely Impact its neuropsychological and associated with significant health known role in immuno-regulation and electrophyaioloqical effecte evaluated as effects in children. Lead effects heme medlatlon of tumorigenesis: and (2) the hcing associated with low-level lead synthesis at several points in its effect of lead on 1,25-(OHh-vitaminD is exposures in non-overtly lead- metabollc pathway, with consequent a particularly robust one, with PbB intoxicated children. None of the impact on the normal functioning of levels of 30-50 pg/dl resulting In available studies on CNS effects, many body tissues. The activity of the decreases in the hormone that overlap indivicfuelly. can be said to provs enzyme ALA-S, catalyzing the rate- comparable degrees of decrease seen in conclueively the t significant cognitive limiting step of heme synthesis. does not severe kidney injury or certain genetic (IQ)or behavioral effects occur in - appear to be eignincentlyaffected until diseases (Roeen. J.F. 1983. The children nt PbB levels <30 pg/dl. PbB levels reach or exceed Metabolism of Ledd in holeted Bone Rather. t he collective neurobehavioral approximately 40 pg/dl. However, Cell Populations: Interactions Between ntudiee of CNS cognitivc [lQ) effects can inhibition of the enzyme ALA-U, which Lead and Calcium. Toxicol. Appl. probably now most reabonably he catalizes the conversion of ALA to Pharmacol. 71:lOl; Rosen, J.F. and R.W. interpreted as being indicative of likely porphobilinogen as a further step in the Chesney. 1983.Circulating Calcitrioi associations between neuropsychologic heme biosynthetic pathway, hoe been Concentrations in Health and Disease. J. deficits in young children and PbB levels observed in humane and other Pediatr. (SI. Louie) 103:l). raqging as low as 3S-50 pg/dl. and of mammallan species at PbB levels even Erythrocyte Py-5-N activity in children possibly some small risk at somewhat below 10-15 pg/dl. with no clear has also been demonstrated to be lower levels (15-30 pg/dl). threshold evident. Correlations between negatively impacted by lead at Also of considerable importance are erythrocyte and hepatic ALA-D activity exposures reeultlng in blood lead levels studiee which provide evidence of inhibition in lead workers at PbB levels markedly below 30 pg/dl (i.e., lo levels changee in EEC brain wave prtlterne and in the range of 12-58 pg/dl suggest that below 10 pg/dl with no evident CNS evoked potentisl responses in non- ALA-D activity in soft tissues (e+, threshold). Extensive reserve capacity overtly lead intoxicated children. brain. liver, kidney, etc.) may be exists for this blood enzyme, such that it Reeearch results demonstrate clear, inhiblted at similar PbB levels at which le not markedly depleted until PbB ntatintically significant associations erythrocyte ALA-D activity inhibition levels reach approximately 3040 pg/dl. between electrophysiological (SW occurs, resulting in accumulatlone of arguing for the Py-5-N effect In and of voltnge) change and PbD levels in the ALA in both blood and soft tissues. Itself as perhapb not belng particularly ranp.? of 30-55 pg/dl and analogous Lead alou affects heme synthesis adverse until such blood lead levels are aseoCotions at PbB levels below 30 pg/ beyond metabolic steps involving ALA, reached. However, the observation of dl (will*no evident threshold down to e leading to the eccumulatlon of porphyrin Py-5-N inhibition is more arguably pg/dl) (LNto, 1981. Effects of Age and in erythrocytes as the result of impaired indicative of wider-spread Impacts on Body Lce;l Burden on CNS Function In iron insertion into the porphyrin moiety pyrimidine metebollem in general !Le., Young Children. 1: Slow Cortical to form heme. The prophyrin acquires a in additional organs and tissues besides Potentials. Ele;tr--.encephawqr. Clin. zinc ion in lieu of the native iron, and blood), such that lead exposures lower Ncurophysiol. 52:220-238). In this ctlse, the resulting accumulation in blood of than 30 pg/dl reeultlng in measurable the presence of electrophysio!oglcal zinc protoporphyrin (ZPP) tightly bound Py-5-N inhibition in erythrocytes may be changes observed upon follov:-up of to erythrocytes for their entire life (120 of greater medical concern when viewed some of the same children two and five days) represents a commonly employed from this broader perspective. years latcr sugReats persistence of such Index of lead exposure for medical In additlon to the above health effects effecte even in the face of !ater declines screening purposes. The threshold for In adults and children, experimental in PbB levels and, therefore, possible elevation of erythrocyte protoporphyrin evidence exislto for carclnogenic actrdty long-term pcrsistence of the observed (EP) levels is well-established ae being (renal tumors) associated with oral electrophysiological CNS changes (Otto, 25-30 g/dl in adults and approximately Ingestion of high doses of lead in at least 1984. Five year follow-up study of 15 pgbl for young children. one mammalian species (Le., the rat) children with low to modorate lead Recently, It has also been and some cases of renal tumors in long absorption: electrophyeiologic demonstrated in children that lead is exposed human lead workera. The issue

F4701 rev. 8-14-85 Federal Register 1 Vol. 50, 219 / Wednesday, November 13, 1 Proposed Rules 40971 No. le85 - of lead carcinogenicity remains to be water standard of 0.050 mg/l may be which would correspond to a drinking resolved in light of the other more viewed as represenllng the upper limit water lead levo1 of 20 pg/L if drlnking extensive epidemiology studies which of acceptability. water were the sole source ol exposuie. did not detect increased tumor Incidence Short-term assessments have not been An uncertainty factor of five could be among lead-exposed human determined for lead because. other than assumed Instead of the tradilinnul factor populations. The (ARC have classified in cases of acute exposures to rather of 10 for human studies. since extremely lead in Croup 3: Inadequate evidence for high lead level*, it generally trike!, a subtle effects in a sensitive carcinogenlclty to humans, sufficient sustained exposure to leod for many subpopulation (infants and children) evidence of carclnogenic!ty to animals days to produce body lead levels were the endpoint8 upon which the levcl (for some salts]. Inadequate evidence for capable of inducing adverse effects. of concern was aelccted. A second acllvity in short-term tests. Lead has At blood lead levels below 30 pg/di. alternative consist.4 of applying an been classifled in EPA's Group B2. many of the different effects reported as uncertalnty factor of '10. resulting In u according to EPA's Proposed Guidelines being assoclated wlth lead exposure drinking water Iced level of 10 ~gil. for Carcinogen Risk Assessment based mlght be argued as separately not belng A second option consials of using 20 upon ovldence of kidney tumors in rats of clear medical sigiilflcance. although pg/dl as the level of concern. converting by the oral route. However, the dosages each are indlcatlve of interferenco by this blood lead level to drinklng wutw that induced the kidney tumors In rats lead with normal physiological letid as WHO done in the first option were very high [beyond the lethal dose processes. On the other hand, the [resuitlng In 125 pg/I). and upplying un in humans) and several extensive collective impact of all of the observed uncertalnty lactor. If nn uncertirinty epidemlohgy studies did not show an effects [representlng potentially factor of 10 was applied. thin would association between lead exposure and impdted functioning crnd depleted correspond to a drinking weter lcnd increased tumor incidences in restwe capacitles of many different level of 13 pg/l. A second ulternalive occupationally exposed workers. In tissues and organs) may. at some point consists of applyinR fin uncertainty view of the above Issues, the RMCL for distinctly below 30 pg/dl, be seen RB factor of 5, corresponding to ti drinking lead will not be set based upon representing an adverse pattern of water lead level of 25 pg/l. carcinogenic endpGi.-*s, instead other effects worthy of avoidance with some A third optlon would be lo set the sensitive endpoints will be the basis. added,margin of safely. The onset of RMCL el zero, since the health effecls The current MCL for lead, under the signs Sf delectable heme synthesis seen are often extremely subtle effects National Interim Primary Drinking impairment in many different organ that may not have a threshold. Water Regulations, is 0.05 mg/l. This systems. indications of increaslng Exposure to lead results in effects on level was based upon an estimation that degrees of pyrimidine metabolism the nervous system. hematopoietic this level in drinking water would interference, signs of dtered nervous system and other physiological contribute 25 to 33 percent of the lead system activity, and interference in processes. Due to these effects and the normally ingested for a child and 33 vltamin-D metabolism start appearing at significant occurrence potential in percent of that in food for an adult. PbB levels around 10-15 pg/dl. All of drinking water, EPA is proposing to The NAS (Drinking Water and these effects could be viewed as continue to regulate lead. EPA is Health, 1984 Vol. V] has stated that the becoming sufficiently adverse to proposing an RMCL of 0.020 pg/l based current drinking water standard of 0.050 warrant avoidance when the various upon the effects of lead in infants as A mg/l may not, in view of other sources effect!, come to represent marked sensitive subpopulation. Comments ure ofenvironmental exposure, provide a deviations from normal as PbB levels requested on all of the issues outlined sufficient margin of safety, particularly exceed 20-25 pg/dl. below and on the additional oplicns for fetuses and young growing children. .Qn additional concern is one recent proposed for setting the RMCL. The WHO guidellnea for drinking water report thet an increase of 6 p~/lin the Questlons for Comment: (1984) suggest that lead should not blood lead levels produced a 1. 1s it most approprietc to base the exceed 0.050 mg/l. This ievel was based concomitant increase in diastolic blood RMCL upon a single health efrect upon a provisional tolerable weekly pressure of approximnlely 2 mm Hg in endpoint. or a constellation of effects? intake of 3 mg of lead per person white males, ages 40-59. 2. What uncertainty fnclor should be established in 1972 by the joint FAO/ If one assumes that Infants consumlng Included In setting the RMCL for Iced? WHO Expert Committee on Food formula reconstituted from tap water are 3. To what extent should possible Additives. Assuming a drinking water the most sensitive subpopulation under carcinogenic effects of lead bc taken lead level of 0.050 mg/l, the 3 mg weekly consideration, and that a blood lead into account as a margin of safety intake would not be exceeded even with concentration of 15-20 pg/dl is the level consideratlon? a daily diet containing 0.3 mg cllead of concern. it is possible to calculate the 4. What is the most appropriate model and the WHO concluded that this lead level In drinking water at which to relate blood lead levcls with drinking allowed for some margin of safety. New this group would be at risk. If 15 pg/dl water levels? data indicate that adverse health effects were selected as the level of concern 5. Are women of child bearing age. thc from lead occur at lower blood lead and using a conversion factor of 6.25 lo developing fetus, the neonate or the onc levels than believed in 1872 when the convert from PbB to lead in drinking to three year old child the most sensitive . tolerable weekly Intake was water (Ryu, et el. Dietary Intake of Lead subpopulatlon(s)? established. and Blood Lead Concentration in Early e. Which of the options presented for EPA's ambient water quality criteria Infancy. Am. 1. Die. Child. 137:888891), developing an RMCL for lead is most (U.S. EPA, 1980. Ambient Water Quality the following cdculation can be made: appropriate plven currently eVllilHble Criteria for Lead. EPA 440/b-80967) for 16 pg/dl x 8,23 e3 94 pg/l, (aseumlng knowledge about Iced health effects tind human health, which considers ingestion consumpllon of 1 liter of water per day). exposures? of water and contaminated aquatic Several alternatives are available in 8. organisms, is 0.050 mg/l. ThIs value was terms of the upplication of an Mercury based upon an analysis which uncertainty factor. One dternative is to Mercury exists in two basic forms: the concluded that the present drinking assume an uncertainty factor of five, inorganic salt and organic mercury

F4701 rev. 8-14-85 46872 Federal Register / Vol. 60, No. 219 / Wednesday, November 13, 1985 I Proposed Rules

com ounds (methyl mercury). Mercu to hove levels above 2 pg/l. In surface The WHO guideline (1984) for leveP s in coal range from io.48,ooo pp'i: , water supplies. mercury was observed mercury in drinking water is 0.001 mg/l through generally it is in the range of at levels of 0.5 pg/l in IO out of 31 and applies to all chemical forms of 2owoO ppb, with soil concentrations aupplles sampled (32%), with 5 supplies mercury. This level was based upon the ranging from 30-300 ppb. Most of the (18%) at levels above 2 pg/l. It le not determination that 2 liters of water knowir areas wlth substanllally elevated clear why the federal surveys suggest a containing 0.01 mg/l mercury would mercury In geologic materials are found substanllally higher fre uency of normally contribute less than 10 percent In California, Nevada, Oregon and occurrence above 2 pg/l than is of the tolerable intake of mercury. EPAs Washington. indicated by the compliance monitoring ambient water quality criterion (U.S The malor use of mercury is in results. The major source of federal EPA. 1980. Ambient Water Quality electrical equipment (batteries, lamps, survey data was the Rural Water Crlterla for Mercury. EPA 440/6-soo58) switches, and rectifiers). It is also used Survey. for human health considering ingestion in the chlorelkall industry as a flowing Healfh Effects. Inorganic mercury is of water is O.oO0144 mg/l. Thie was cathode for electrolytic depositlon of poorly absorbed through the gastro- based upon the ingestion of water and salt brine into chlorine. sodium inleetinel tract, does not penetrate cell contaminated aquatlc organisms which hydroxide and hydrogen. membranes rapjdly and is less toxic contain methyl mercury. Mercury may also enter the than methyl mercury. The principal environment from mining, smelting, and target organ of inorganic mercury is the Exponuru to inorganlc mercury fossil fuel combustion. Natural kidney. Methyl mercury compounds compounds at high levels results in renal processes such as volcanic activity, exert their toxlcologlc effect on the effects. Because inorganic mercury is the geothermal octivity and volatilization central nervous system. Contamination form of mercury detected in drinking from mineral deposits result in mercury of fish and shellfish by methyl mercury water, has widespread occurrence and entering the atmosphere. compounds has resulted In Minamata may have adverse health effects, a Analytical Methods. Analytical Disease in Japan. characterized by revised regulation is proposed. An methods available for analyzing mental disturbances, ataxio, dlsturbence RMCL for inorganic mercury of 0.003 mercury in drinking water include the in s eech and hearing impairment. mg/l is proposed, based upon a manual cold vapor and automated cold Srl ort-term assessmen! values were provisional AADI of 0.0055 mg/l with vapor tezhniques. not calculated for mercury due to data on human exposure factored in Human Exposure. Mercury is lnsufnclent data. A provisional AADI (0.0043mglday via the diet and 0.001 introduced into the air from both natural was calculated for inorganlc mercury mglday via air). and anthropogenic sources. Ambient based upon a study (Dmet. et el. 1078. Question for Comment: levels of mercury range between 10-20 Immune Type Glomerulonephritis 1. Should a separate RMCL be ng/m? In areas near coal-fired power Induced by Mercuric Chloride in the proposed for organic mercury plants. levels be as hlgh as 1000 ng/m? Brown Norway Rat. Ann. Immunol. compounds? Usually high concentratlons of 10,OOO- 120C:777-792) in which rats were 15,O0O nglm' have been reported near exposed to Inorganic mercury salts for 8 9. Nitrate and Nitrite rice fields where mercury fungicides to 12 weeks through subcutaneous Nitrate is the more stable oxidized have been, used and in the vicinity of injection. The primary endpoints mercury mines. form of combined nitrogen in most evaluated were antibody formation and environmental media. nitrogenous The average daily absorption of proteinuria, with proteinuria seen at Most atmospheric mercury for an adult male materia1s In natural waters tend to be doses of 100 pg/kg and above, but not at converted to nitrate. and, therefore. all is estimated to be approximately 320 ng, M) pg/kg. In the 50 pg/kg exposure based upon an average atmospheric sources of combined nitrogen group, a total of 38 doses totalling 1800 (particularly organic nitrogen and conecntration of 20 ng/m? a ventilation pg/kg were Injected over the M-day rate of 20 ma and the assumption that 80 ammonia) should be coneidered as eriod. The NOAEL was determlned to potential nitrate sources. Nitrates occur percent of the inhaled rate is absorbed. e W pg/kg/day and a factor of 0.739 to Food is a primary source of exposure adjustE for the percentage by weight of naturally in mlneral deposits (generally to mercury. and the major dietary source mercury in mercuric chloride was sodium or potassium nltrate), in soils, appears to be the consumption of fish. included in the development of the seawater, freshwater systems, the The FDA estimated the dietary intake of provisional AADI. An uncertainty factor atmosphere and in biota. Lakes and mercury to be 4.3 pg/day for the adult of IO00 was applied because other static water bodies usually have male (excluding beverages), of whlch 3.8 proteinures. an adverse health effect, less than 1.0 pg/l of nltrate/nitrogen. pg comes from meat, fish, and poultry occurred at concentratlons of mercury (Generally, the occurrence of nitrate is categories. only twice the NOAEL. To compensate measured and reported in terms of its Almost all mercury detected to date in for the difference in abaorptlon between nitrogen content: 1.0 pg/l of nitratel drinklng wa: ,r is In the form of subcutaneous and oral exposure, an nitrogen is equivalent to 4.4 pg/l of inorganic mercury. Compliance absorption factor of 10 was used, nitrate.) Ground water levels of nitrate/ monitoring indicates that 12 ground resulting in a provisional AADI of 0.0055 nitrogen may range up to 20 pg/l or water and 11 surface water supplies mg/l. This value was based upon more, with higher levels have reported levels above 2 pg/L All of inorganlc mercury because almost all characteristically occurring in shallow the ground water supplies serve leas mercury in drinking water is thought to aquifers beneath areas of extensive than 5.O0O people whereas five of the be in the form of inorganic mercury. development. Major sources of nitrates surface water supplies serve more than The IARC have not evaluated the or nitrite in drinking water include 10,OoO people. carcinogenic potential of mercury. fertilizer, sewage and feedlots. There is only limited federal survey Mercury has been classified in EPAs Analytical Methods. Anal yt ice I data on mercury. Of 108ground water Group D, according lo EPA'a Proposed methods avallable for analyzlng nitrate supplies sampled between 1978 and Guidelines for Carclnogen Rlsk and nitrite in drinking water Include the 1980,32(30%) were found lo have levels Assessment+based upon Inadequate colorlme tric bruclne spectrometric above 0.5 pg/I, and 14 (13%) were found data in animals and humans. cadmium reduction, automated

S-074999 m72(M)(t2-NOV-85-I5:23~) F4701 rev. 8-14-85 Federal Register I Vol. 60, No. 219 I Wedneaday, November 13, 1985 / Proposed Rules 46973- hydrazine reduction and automated The effects of methemoglobinemia are Many studies have demonstrated thet cadmlum reduction techniques. rapidly reversible and there are, nitrate/nitrite adminietered with Human Exposure. A daily res iratory therefore, no accumulative effects. nitrosatable compounds are intake ranging from 26 to 70 pghay There are no suitable data for carcinogenic in anlmnls. However. the based upon reported urban and calculating one-day assessment values carcinogenic potentiel of nitraIu/nitrite nonurban levels of dtrogen oxldee has tor elther nitrate or nltrlte. However, the when administered in the absence of been determined. ten-day assesement values for both nitrosatable compounds has not been Food is generally recognized as the nitrate and nitrite will be protective for demonstrated. The IARC huve not m.i]or source of nitrate intake. The one-day exposures. classified nitrate/nitrite for potentiui estimated dietary intake is A study by Craun, et el. (lQ81)was carcinogenicity. Nilrele/nilrile have approximately 100 pg/day, wlth 85 to 80 selected as the basis for calculating ten- been clasaified in EI'A'a Group D, percent coming from vegetables and 9 day assessment values for nitrate in according lo EPA'e Proposed Guidciines percent from cured meats. Most adults. Craun, et el. (1981) observed that for Carclnogen Risk Aasessmcnt. biiscd vegetables contain nitrate, Beets, celery, nitrate levels up to 111 pg/l nitrote/ upon inadequate data in unimuls und lettuce, radishes, and spinach were nltrogen did not produce methemoglobin humans. reported to have levels ranging from 120 in one to eight year old children. The The current MCL for nitrute/nilrogen. to 835 ppm (dry weight). Much lower data of Craun, et el. (1981) are under the National Interim Primary levels (10-24 ppm) were reported for appropriate to use as the basis for a ten- Drinking Water Regulations, ie 10 mg/I. tomatoes, potatoes and peas. day adult assessment of 111 pg/l nitrate- This level was bwed upon human ciiw Compliance monltorlng Indicates that nitrogen because the child and the adult studies in which fatal poisonings in approximately 570 community public would be expected to have similar Infants have occurred following water supplies are providing water with responses to nitrate. An uncertainty ingestion of well waters containing nilrate/nilrogen levels above 10 pg/l(44 factor was not employed in the nitrate concentretione greater than 10 pg/l nitrate). mg/l nltratelnitrogen. Three national surveys conducted derlvatlon of the number since the most sensitive subpopulation, infants, are The WHO guidelines are 10 mg/l for between and 1980 indicated that 1~69 considered separately and would not nitrate/nitrogen and 1 mg/I for nitrite/ 835 out of 1,479 (56% ground water supplies had nitrate nitrogen levels need lo be protected under this number. nitrogen. The basis is that undesirable 1 The ten-day adult assessment for increases in methemoglobin levels in above 0.3 pg/l (nitrate levels of 1.32 pg/ The mean nitratelnitro en levels nitrlte can be calculated using the ten- blood occur at levels from 10 mg/l to 20 I). mg/l nitrate and the ingestion of nitrite above 0.3 pg/l was 1.8 pg$I. and values day nltrate dssessment and assuming a ranged up lo about 22 pg/l. There were 10 percent conversion of nitrate to leads to a more eapid onset of clinical 20 ground water supplies with levels nitrite. Thus, the len-day assessment for effects and thus the guideline value above 10 pg/l(l.4%). nllrlle in adults is 11 pg/I nitrite should be correspondingly lower (I mg/ In these same surveys, nitratel nitrogen. 1). nitrogen levels of 0.3 pg/l were found in As the provisional AADI for both Nitratelnitrite compounds have 175 out of 409 surface water supplies nitrate and nitrite is based upon short- demonstrated adverse toxic effects in sampled (42.8%), with a mean value of term exposure in the infant, it io infants. Due to potential toxicity and 1.6 pg/L The nitrale/nilrogen values in appropriate to use the provisional AADl wide spread occurrence in water. surface water raeged up to 21 pg/I. as a 10-day assessment for the Infant. revised drinking water regulations will There were 5 supplies (1.2%) with levels A provisional AADl was calculated be proposed. The RMCL will be based above 10 pgll. The presence of nitrite In for nitrate/nitrogen based upon the upon non-carcinogenic effects and drinking water at slgnlncant levels Is Infant (4 kg] as a hlgh risk RMCLs of 10 mg/l for nilrele/nilrogen unusual and would indicate probable subpopulation. The study used was an and 1 mg/l for nitrite/nitrogen are organic contaminelion (Le., sewage), epidemiologic study in which 300 cases proposed. Data on human exposure lack of disinfection (reducing of infant methemoglobinemia were were not factored in the RMCL because conditions] and probable bacterial surveyed (Walton, C. 1951. Survey of the provisionel AADl was based upon contemlnation. Literature Relating to Infant an epidemiologic study in which HealfhEffects. The lorlclty of nllrate Methemoglobinemia due to Nitrate exposure via the air and diet is already in humans is due to the body's reduction Contaminated Water. Am. 1. Pub. Health taken into account. of nitrate to nitrite. This reactlon takes 41:986-968). No cases were associated Questions for Comment: place in saliva of humans at all ages and with drinking water containing less than 1. Should the carcinogenic potcmtial of in the gastrointestinal tract of infants 10 pg/I of nitrate/nitrogen. Using IO mg/ nitrosatable compounds influence the during the first three months of life. The 1 as a NOAEL without the application of proposed RMCLs for nitratelnitrogen toxicity of nitrite is demonetrated by an uncertainty factor (large number of and nitrite/nitrogen? If so, how? vasodllatory/cardiovasculareffects at subjects exhibiting no signs of toxicity), 2. The Criteria Uocumenl on Nitrate/ hlgh dose levels and a provisional AADI of 10 mg/l was Nitrite outlines an alternate methemoglobinemia at lower dose determined for nitrate/nitrogen. This methodology for calculation of short- levels. Methemoglobinemia is an effect value would also be protective for the term asseesment values. Is this an in which hemoglobin is oxidized to infant for short-term exposures (1- and appropriate approach for calculation of methemoglobin. resulting in asphyxia. 10-days). For nilrite/nitrogen, the same these numbers? Infants up to 3 months of age are the study was used. with an uncertainty 3. What Uncertainty factors should bc! most susceptible subpopulation wlth factor of 10 applied to the NOAEL (IO applied in the calculation of the AADls regard to nitrate. This Is due to the fact mg/l), due to the demonstrated direct for nitrate and nitrite? that in the adult and child. about 10 toxicity of this chemical. resulting in a percent oi ingested nitrate is provisional AADl of 1 mg/l, This value 10. Selenium transformed to nitrite, while 100 percent would also be protective for the infant Selenium occurs in U.S. soils at of ingested nitrate can be transformed to for short-term exposures (1- and 10. concentrations ranging from 0.03 to 0.8 nitrite in the infant. days). ppni with very little difference between

F4701 rev. 8-14-85 46974 Federnl Register / Vol. 60, No. 219 / Wednesday, November 13, 1086 / Proposed Rules

the soils of eastern and western States. the 1078 CWSS, 12 out of 258 ground consumption of 2 liters 01 water per day. However. in the western States, the water supplies (4.7%) had levels above 6 A IO-day assesement for the child of 45 more alkaline soils tend to make pg/l and 2 (0.8%) had levels above IO pel1 was calculated based upon the selenium more wator aoluble and pgll. In the Rural Water Survey (RWS), same etudy, aeeuming consumption of 1 increased plant uptake and 30 out of 71 ground water supplies liter of water per day. accumulation occun. Sedimentary rocks (42.3%) had levels above 6 pg/1 and 8 A provisional AADl was calculated have higher concentrations of selenium out of 71 (11.3%) had levele above 10 pg/ based upon a human study (Yang, et el. than do igneous rocks. Of the 1. 1983. Endemic Selenium Intoxication of sedimentnry rocks, .shales fwquently The 1888 CWSS reported that Humane in China. Amer. jour. Clin. Nutr. contoin more selenium than limestones eelenium was found in all 108 aurfaco 37872461) which examined aelenium or Sandstones. water supplies eempled, at levels toxicity and dsficiency cffects in China. Most of the commercial eelenium rangin from 1.0 to 10 pg/l (mean value, The minimum daily selenium intake produced in the U.S. is recovered from 4.8 pgfl). In the 1078 CWSS, none of the level in an area of chronic selenoeie was copper ores. Only 258 metric tons were 64 supplies sampled were found to have reported to be 3.20 mg. A provlsional produced in 1081; an additional 338 measurable levele of selenium: the AADl of 0.108 mg/l was celculeted metric lone were imported. The reported minimum quantifiable levels rangod using 3.20 mg/day a8 a LOAEL, consumplion of selenium for 1981 wan from 2.5 lo 5 pg/l. In the RWS, 2 out of coneumption of two liters of water per for electronic and photocopy 21 eurface supplies had levels above 6 day and an uncertainty factor of 15. This applications, glass manufacture, Pe/l* uncertainty factor was applied to a pigments, chemicals, pharmaceutlcals, Ileahh Effecte. Selenium has toxic human study with a great deal of data. fungicides and as feed additives. effects at high doeo levels and le An uncertainty factor of 10 would Selenium releasee to the environment nutritionall:; eesential at low levels. troditionally be applied, however in this renull from coal (coal contains 1.6-3.3 Acute and chronic toxic effects have Instance an uncertainty factor of 15 was ppm) burning, non-ferrous mining and been observed in animala. In humans, applied due to data which euaests that emelting. and the remainder from little data exists on acute toxicity, while eelenium ingested in food may be selenium refining, glaae manufacture a recently completed study on endemic ehaorbed leea efficiently than selenium and fuel oil combustion (1070 estimate). selenium intoxication in humans In Ingested in water. This information Analytical Mefhods.Analytical Chinn (Yang, C.,et el. 1083. Endemic would support the use of an uncertainty methods available for analyzing Selenium Intoxication Humans In of factor greater than 10. selenium in drinking water include the China. Amer. jour. Clin. Nutr. 37:872- gaseoue hydride atomic absorption, Naturally occurring selenium 881) reported that chronic toxicity was compounds (selenate and aelenlte) have furnace atomic absorption and observed in individuals consuming a not been shown to be carcinogenic in inductively coupled plasma atomic dally average of 4.8 mg eelenium through emission spectrometry techni uee. animals. On the contrary, many studies the diet, with a minimum selenium have ehown theee selenium compounds Human Exposure. In genera,9 selenium intake of 3.2 mg. levels in the air in the U.S. appear to be In animals, selenium deficiency to result in the inhibition of tumors of below 5 ng/ms. One study showed that results in congenital white muscle various types, including tumors of the levels near a coal-fired power plant, a disease and other diseases. A level of skin. liver, memmary glands, colon and major source of selenium to air, were 0.1 mg Se/kg food has been considered lung. Selenium sulfide. a manufactured <3 ng/m*. Three reportd estimates of to be the general level of dietary product not normally found in water, daily rspiratory intake of eelenium are requirements in animals. Selenium is was found to be positive in the National 0.02.0.07 and < 1 pg. coneldared to be an eseential element Cancer lnetitute bioassay by gavage The selenium content of foods ranges for human nutrition, with an (NCI, 1080. Bioassay of Selenium Sulfide from undetected or trace levels (~0.001 approximate intake level of 100-200 pg/ (gavage) for Possible Carcinogenicity. ppm) lo dpproximately 1.0 ppm. Higher day adequate to prevent deficiency in a NCI Technical Support Series No. 164. levels (0.2-1.0 ppm) are reported for the 70 kg adult. The NAS (Drinking Wafer JUTP No. 80-17). The IARC has not meat, fiah, poultry, and grains and cereal and Health, 1980. Vol. 111) have claesified selenium for potential food claeses. A recent FDA market eetimated an adequate and safe intake carcinogenicity. Selenium has been basket survey ieported that dietary of selenium for adults of 0.05 to 0.20 me/ claesified in OPA's Croup D, according intake for the adult male wan 152 pg/ day with correspondingly lower intakes to EPA's Proposed Guidelines for day, of which 52 percent comce from for children and infants. Carcinogen Risk Aasesment, based upon grains and cereele, 38 percent from A 1-day assesement was not inadequate data in animals and humane. meat, fish and poultry and 10 percent calculated for eelenlum due to The current MCL for selenium. under from deiry products. Other studies have insufficient data. The values calculated the Natioiial Interim Primary Drinking reported selenium intake through the for the 10-day levels are considered Water Regulation, is 0.01 mg/l. This diet ranging from 80 to 150 pg/day protective for the I-day exposure period. level was based upon eigne of selenium (Drinking Waferand Health, 1080. Vol. A 10-day aseesement for the adult was toxicity at an intake of 0.7-7 mg/day 111: Welsh. et al. 1981. Selenium in Self- calculated based uFon a etudy and an assumed aelenium Intake of 200 Selected Diets of Maryland Residents. (Halvereon. et el. 1See. Toxicity of Pg/deY. Jour. Am. Dietlc Asen. 7B277-285). Selenium to Post-weanling Rats. The WHO guideline (1084) for Compliance monitoring indicate that Toxicol. Appl. Pharmacol. 9477484)in selenium is 0.01 mg/l. The WHO stated 150 ground water and 8 eurface water which rate were fed sodium eelenite for that current estimates of selenium intake supplies contain selenium levels above e weeka and levels of 4.8 mg/kg feed range between 130 and 200 pg/day and 10 rg/l. (0.41 mg/kg/day) produced no adverse the maximum daily selenium intake in the lW Community Water Supply effects as compared with controls. A 10. from drinklng water should not exceed Survey (CWSS), 854 out of e71 ground day ansessment for the adult of 144 pg/i 10 percent of the recommended water eupplies (07%) had selenium at was determined, using 0.41 mg/kg day maximum daily dietary intake of 200 $8. levels ranging from I to 85 p /I as the NOAEL an uncertainly factor of Assuming an intake of 2 liters of water (mean of the poeillves was 2.7 pgrl). In 100 baaed upon an anlrnal study and per day, the WHO determined a

-74999 0074(04)( 12-NOV-85-.15:23:t3) F4701 rev. 8-14-85 - Federal Reglster I Vol, 60, No. 218 I Wednesday, November 13, 1985 / Proposed Rules 48975 guideline value of 0.01 mg/l. EPA's and dietary supplements. In addtion, potential of aluminum or its salts to ambient water quality criteria (U.S. aluminum cookware, utensils and induce mutagenic or cercinogcnic effeclr EPA. 1980. Water Quality Criteria storage containers can be sources of the have yielded negative results. Document for Selenium. EPA 440/&80- metal in foods. Numerous studies are In the human, deposition of alumlniim 070) for human health is 0.010 mg/i in available on dietary intake of aluminum In the brain has been su~ualodus un agreement wlth the NIPDWR. Current reported levels ranglng from less than etiological factor in the neurologic data suggests that selenium is an 1.63 lo as much as 100 mg/day. The disorders. Alzheimer'e diseasc! rind essential nutrient and has anti- average adult intake from the diet, dialysis dementia in patients with carcinogenic effects in animals. These however, is calculated to be chronic renal failure. This hypothesis guidelines (WHU and ambient water approximately 20 mg aluminum per day. has not been confirmed end the question quality critrria) did not take the Aluminum commonly occurs in of the relationship between aluminum beneficial effects of selenium into finished drinking water eupplies, and certain neurologicsi disorders ie one account. especially surface waters treated with that is receiving a great dcul of uttontion Selenium rxposure high levels alum. Use of this compound can at by the medical reserirch community HI results in chronic adverse health effects. lncrcase (or decrease) the level of the preeent lime. In addition, thc Agency EPA is proposing lo continue reflulation aluminum in finiahcd waters. IS purRuinR lines of investigation in of se!enium because of its potential In a recent EPA study (1983) of the occurrence of aluminurn In drinking experimental studies which nhould shed adverse health effects and widespread light on the dose-response relationships occurrence. An RMCL of 0.045 mg/l is water, an analysis was conducted of in animals following exposure to proposed, based u on a provisional randomly selected community water systems. Levels of aluminum (mg/l) in aluminum salts in drinking wutcr. Since. AADl of 0.108 mgL, with data on at the present time, there rife no human exposure factored In (0.126 me/ finished drinking water determined for day via the diel). various types of water systems and adequate dose-response dolii ~vuil~blc Questions for Comment: sizes are shown below: from which to estimate an AADl for 1. Do58 the proposed RMCL for ionic aluminum in drinking water, EPA selenium reflect an adequate balance is proposing not to estublish an RMCI, betwean the toxicity and deficiency ond primary reaulation. Aluminum will Orarnd Wa1w-no coagulanl...... be reevaluated at a later dale. after the effects of the compound? Sucace Watw-no coegulsnl ...... 2. It is more appropriate to apply a Sucrce Walw-Alum coagulant ...... 0014-2 e70 I O.Il2 results of the animol studies become .... 0.015-0.081 . 0038 traditional uncertainty factor of 10 for available. selenium. resulting in an RMCL of 87 A guidance level of 0.05 mg/l is rs/l? Median aluminum levels (mg/l) by recommended for aluminum such that population category (both ground water treatment is fully effective in removing C. IOC's for Which RMCLs An? Not and surface water) were as follows: coagulated materials to avoid setting of Proposed particles in the distribution syetem. This 1. Aluminum value is not based upon health and has Aluminum is the th!rd most abundant been recommended by the American element in the earth's crust and occurs Waters Works Association as a goal for potable water. The Wf10 hiis moat commonly as aluminosilicates. 2510999 ...... <0014-0.O3l e0014 such as clay, kaolin, mica and feldspar 10.O00 lo 99.999 ...... <0014-0264 recommended a guideline value of 0.2 ion.000 IO 888.989 ...... 1 l.OOO.O00 ...... <0.0144.W2 mg/l baaed upon water discoloration. aluminum compounds and alloys 2. Cyanide. cyanides are organic or inorganic compounds that contain the include production of aircraft, utensils, A review of earlier surveys of finished and electrical conductors. The metal cyanide moiety, -CN. Organic drinking water supplies across the U.S. compounds having this functional group powder is used in explosives, pigments, IlB02, 1989, 1977) indicates mean levels are referred lo as nitriles. Cyanides are paints and coatings and putties. of a!uminum ranging from 0.073-0.104 Aluminum compounds (e.g., aluminum pg/I. Levels of the metal in individual formed readily in many industrial sulfate) are commonly used in drinking samples ran ed from 0.003-2.4 pg/l. processes and can be found in a variety water treatment for coagulation. Health Efbcts. In general, aluminum of effluents. Cyanide commonly occurs Analytical Methods. Analytical is considered to possess low acute in water as hydrocyanic acid (IICN). the methods available for andyzing toxicity for the normal individual cyanide ion (CN.'). simple cyanides. aluminum in drinking water include the following oral exposure. Oral Ldaos for metallocyanide complexes or as simple flame atomic absorption, furnace atomic aluminum chloride in several animal chain and complex ring organic absorption and inductively coupled species ranged from 380 lo 780 mg/kg. molecules. emission spectrometry techniques. Few data exist from animal studies Cyanide production in the U.S.in 1978 Human Exposure. Levels of elemental following eubchronic or long-term oral exceeded 700 million pounds. The major aluminum in the ambient air over the exposure. These suggest primarily that industrial users of cyanide in the U.S. continental U.S. have been reported to effects may be seen at relatively high are the producers of steel. plastics. range from 0.14-8.0 ug/m? Levels of doses on phosphorus balance;and that synthetic fibers and chemicals and the aluminum in metropolitan areas were an the adverse sequelae are. in fact, the electroplating and metallurgical order of magnitude greater than those in result of this change (e+, osteomalacia). industries. In addition to these rural areas. Background atmospheric No evidence of fetotoxicity or industries. cyanide wates are discharged concentrations have been measured teratogenicity has been observed in into the environment from the pyrolysis from 0.005-0.032 ug/m? animals following oral exposure. On the of a number of synthetic and natural Aluminum is naturally present In other hand. there is a report of materials and from chemical, biological, nearly all foods. Other significant decreased sperm count end motility in and clinical laboratories. Cyanide in sources of the metal In the dlet are rets exposed to 2.9 mg/kg by gavage for drinking water is oxidized by chlorine at baklng powder, food additivee, anlaclds, 8 months. Studies lo evaluate the basic pH to cyanate.

S-074999 0075(04W12-NOV-85-I5:23:l~) F4701 rev. 614-85 - 48978 Federal Regleter / Vol. 60, No. 219 / Wednesday, November 13, 1Q65 / Proposed Rulea

Anal fical Mefhods,Analytical dose males and females, respectively, account for the absorption differences metho dya available for analyzing cyanide and 7.6 and 10.8 mg/kg body weight between cyanide exposure via food and In drinking water include colorimetric cyanide for the high dose males and drinklng water? and automated electrode techniques females, respectively. At these dose 4. Should EPA set an RMCL for with dislillation. levels, no treatment-related toxic effects cyanide despite the fact that it has been Humon Exposure. No information is including histopathologic lesione were detected at levels far below the available on levels of cyonlde in the observed. A provisional AADl of 0.75 provisional AADI? ambient air. mg/l cyanide was calculated from the No data are avnilable on the NOAEL of 10.8 mg/kg cyanide with an 3. Molybdenum occurrence of cyanide in foods. Except uncertainly factor of MK) (an additional Molybdenum occurs naturally as for certain naturally occurring nitriles in uncertainty factor of 6 was included molybdenum sulfide and as molybdenite Innls. it is unlikely that cyanide would because cyanide was given in the diet salts. Uses include the manufacture of re found In foods of the US. rather than in drinking water) and speclal steel for tools, boiler plate, and Cyanidc is relatively uncomon in most assuming human consumption of 2 lilers propeller shafts, tungsten, x-ray tubes, U.S. water supplies. In 2,605 water of water per day. filaments and non-ferrous alloys. samples. the Community Water Supply Potassium cyanide wen negative for Molybdenum is also used as an additive Survey (CWSS) of 888 U.S. public water mutagenicity in Solmonello In lubrlcants. supply systems in 1970 revealed the typhirnurium and Bocillus subtilis. The Anolytical Methods. The analytical highest cyanide concentretion found IARC have not classified cyanide for methods available for analyzing won 8 pg/l and the average otential carcinogenic effecte. Cyanide molybdenum in drinking water are the concenlration wan 0.08 pg/l. tiowever, gee been claseified in EPA's Group D, flame atomic absorption, furnace atomic cyonlde has beon found in surfaco according to EPA's Proposed Cuidellnes absorption and inductively coupled waters end is present in waste waters. It for Carcinogen Risk Assessment, based plasma atomic emission spectrometry is soluble in water and used in large upon inadequate data in animals and techniques. quantities across the country. Although humane. Humon Exposum. Molybdenum is it is blologically and chemically The WHO guideline for drlnklng degradahle, it has appeared in some considered an essential trace element In woter is 0.1 mg/l. This value was baaed humane. The NAS has estimated the drinkin8 water systems. upon 4.7 mg cyanide/day which has Heolth Effects.Cyenidee are readily dietary intake of molybdenum to range been recorded to not be harmful to from 0.1 to 0.48 mglday. In a separate absorbed from the lungs, the gastro- 2 humane. Assuming consumption of study, an average daily intake of 0.18 intestinal tract and the skin by trnimals liters of water per day, the WHO and humans. The toxic effects of concluded that cyanide concentrations mglday was estimated based on an analysis of 300 samples of 40 different cyanide occur due to the combination of of 2.35 mg/l could be consumed in foods, collected from 5 supermarkets cyanide with cytochrome in the cell, water. Allowing for a safety factor, the with resulting hypoxia. Cyanide may be WHO considered a guldehe value of over a %year period. detoxified in the liver by rhodanese, an 0.1 mg/l lo be reasonable. EPA'e In an early study (1884) of finished enzyme in the liver which metabolizes ambient water quality criteria (U.S. water supplies of the 100 largest cities in cyanide to form a less toxic compound, EPA. 1980. Ambient Water Quality the United States, levele of molybdenum thiocyanate. The major route of cyanide Crtterta for Cyanide. EPA 440/6-60-037) were reported to range from not elimination from the body is via urinary for human health considerlng ingestion detected to 66 pg/l (median-1.4 pg/I). excretion of thiocyanate, of water and contaminated nquatic In a later 6-year study (1970) of 380 No suitable data wero identified for organisms is 0.2 mg/l. This value was finiehed waters, 29.9% had meaeurable the culculnlion of a one-day aesessment. updated (February 1984.48 FR 45511 and levels of molybdenum; concentrations Although there are date available to the proposed revised value is 3.77 mg/i ranged from 3 to 1,024 pg/l (mean=85.9 calculate the mday asseement value, it based u on the same study used to pg/l). Reeults of a recent and extensive is iecommended that the 1-day and 10- derive t1e provisional AADI. The etudy (1978) of tap waters of the U.S. day levels be set at the AADl of 0.75 difference in the two numbers is due to showed molybdenum in 30 percent of mg/I for the 70 kg adult consuming 2 the addition of an additional uncertainty the samples, with levele ranging from 1.1 lilers of water per day. Ueing the same factor of 6 in the derivation of the to 62.7 pg/l (mean~8.0&I). Accordlng data base, the I-day and 10-dey provisional AADI since cyanide was lo the NAS, molybdenum in drinking essesement volue for the 10 kg child given in the diet rather than drinking water, except from highly contaminated consuming 1 liter of water is calculated water. sources (@.e.,molybdenum mining IO bC 220 pg/l. Cyanida has rarely been detected in wastewater) is not llkely to constitute a A provisional AADl was calculated drinking water supplies, and when it has significant portion of the total human based upon a two-year study in which been detected it has been at levels so far daily intake 0: the element. rats were administered diets containing below the provisional AADl that an Health Effects. Molybdenum le 0,100 or 300 mg/kg hydrogen cyanide RMCL for cyanide would almost readily absorbed through the (Howard, J.W. and Hanzel, R.F. 1955. certainly be useless. Thus, EPA has gastroinleatinal tract, with the highest Chronic Toxicity for Rata of Food decided not to propose an RMCL for concentrations in the liver, kidneys elid Treated with HydroRen Cyanide. J. cyanlde at the present time. hone. There is no apparent Agric. Food Chem. 3:325:329). Average Questions for Comment: bioaccumulation of molybdenum in doseo due lo volatilization were 1. Are there sufficient health effects animal or human tlesues. A steady date calculeted to be 78 mg/kg/dlet hydrogen and exposure Information upon which to concentration is reached when Intake is cyanide (73 mg/kg/diet cyanide) for the base an RMCL? increeeed, and when the dose is low dose group and 187 mg/kg/diet 2. Is the assumption of 100 percent withdrawn, tissue concentrations return hydrogen cyanide (180 mg/kg/diet contribution from drinking water to normal levels. The principal route of cyanids) for the high dose group. The reaeonable? excretion is via the urine. estimated daily doses were 3.8 and 4.8 3. le it appropriate to apply an Acute toxic effects from exposure to rng/kg body weight cyanide for the low- additional uncertainly factor of 5 to molybdenum consists of damage to the

F4701 rev. 8-14-66 - Federal Register / Vol. 60, No. 219 / Wednesday, November 13, 1985 / Proposed Rules 46077

Ilver, kldneys and sometimes adrenal8 contains a lead chromate, sulfnte and nickel in drlnking water include the and spleen. Ruminants are more molybdenum compound. This compound flame atomic absorption, furnace atomic sensitive to molybdenum than are was shown to produce tumors by absorption and inductively coupled monogastric animals. Subchronic toxic subcutaneous injection: however since plasma emission spectromelry effects In animals consist of a decreased both lead and chromate aro present In lechnlques. Rrowth rate. male Infertility, weight loss the compound it Is possible that the fluman Exposure. Levels of nickd in and bone or Joint abnormalities In effect was due to these metals and not the amblent air of 237 urban and 47 forelegs. molybdenum. The IARC have not nonurban localities In the U.S.. for the Molybdenum is an essentlal element classlfied molybdenum for potential period 1970 to 1974. were dctcrmlned by at low doses and has toxlc effects at carcinogenicity. Molybdenum has been EPA. Arithmetic means for erich of these high dose levels. The NAS (Drinking classified in EPA’s Group D. according years renged from c.ooB to 0.016 pR/m3 Water and flcolth. 1980, Vol. 111) have lo EPA‘s Proposed Guidelines for for urban areas and 0.002 to 0.001 pg/ms estimated an adequate and safe inteke Carclnogen Rlsk Assessment based for nonurban ereas (delection limit. level of 0.15 to 0.50 mg/day for adirlIs upon inadequate data In animals nild 0.001 pg/m?, For any given year, the and children 11 years and older, humans. urban values were 3 to 4 times thrit of One-day assessments of 2.7 m /I The WHO has nnt recommended a the nonurban areas. [child) and 9.5 mg/l (adult) havefwan limll for molybdenum in drinking water. Reported dletary levels of nickel for calculated lor molybdenum based upon The NAS also has not recommended a U.S. consumers range from 165 to Roo a study (Fairhall, et el., 1945. The level of mol bdenum in drinking wetcr pg/day. Average values rungc from 400 Toxicity of Molybdenum. Pub. Hlth. other than t f: B safe inteke level for to 500 pglday. Nickel Is common in H Serv. Bull.) in which a slngle nutritional effects. According to the wldc varicty of foods. Food proccasing intraperitoneal dose of 20 mg NAS (1980), “Our understanding of methods, however, may udd additional molybdenum (e0mglkg ammonlum chronic molybdenum toxicity or levels through leaching from stainless molybdate) did not show any apparent deficiency is presently extremely steel processing equipment. effects. Other studies have shown that limited. This topic should be studied. A summary of levels of nickel in the LD for orally ingested ammonium Further studies should also be 380 molybdate is about three times higher U.S. drinking water supplies for the conducted to determine the interaction years 1902 lo 1967 was prepared the than for molybdenum trioxide and of molybdenum with other elementa and by calcium molybdate, the forms commonly U.S. Department of Interior, Levels of nutrients In humans.” nickel ranged from to 490 pg/L with a found In water. Thus, a NOAEL of 27 1 EPA has decided not to propose an mean of 34.2 pg/I. The frequency of mg/kg was used, calculated by dividing RMCL at this time for molybdenum the NOAEL for ammonium molybdate because of the Inadequate data on detection was 4.6 percent. (80mg/kg) by three to account for the toxicity of the compound. A provisional Levels of nickel have been reported for 969 public water supplies in 8 potential differential toxicity. An AADl of 0.10 mg/l was determined uncertelnty factor of 100 was applied based upon an epidemiological study in metropolitan areas for the years 1909 to based upon a NOAEL from an animal which only one dose was examined and 1970. The average value was 4.8 pg/I study. with an assumed water no effects were noted. Thls study did and the maximum was 75 pg/L consumption of 1 liter per day (child) not determine at what level effects may Health Effects. The absorption of and 2 liters per day (adult). have been seen. Animal studies dietary nickel from the gastrointestinal Sufficient data were not available examining chronic toxicity are not tract appears to be quite low with the from which to derlve I&day available and thus an AADl could not majority of nickel excreted in the feces. asaesamcnts. Ten-day numbers were be calcuhled based upon these effects. Laboratory studies have demonstrated calculated by dividing the I-day Acute animnl etudies are available but depressed body weight gem. alterations numbers by 10, resulting in values of acute studies are not an adequate basis in hematology parametcra, cytochrome 0.27 and 0.96 mg/l for children and for determining an AADI. oxidase activity and iron contents of adults, respectively. Question for Comment: organs following high dose oral A provisional AADI was calculated 1. Should a Health Advisory be exposure. for molybdenum based upon a human developed for molybdenum or is there Insufficient dRta ere available for the study (Chappell, W.R., et al., 1878. sufficient health effects Information derivation of 1-day assessments for Human Health Effects of Molybdenum upon which to base an RMCL? nickel. The avallable short-term (1-15 in Drinklng Water. Cincinnati, OH. US. days) toxicity studies of nickel using the EPA-A-78008) in whlch blood 4. Nickel oral route of exposure reported only molybdenum levels were within normal Elemental nickel Is not commonly acute cffects (LDw]. ranges and no adverse effects were found in nature as the pure metal, but The 10-day asseasmcnta for the 10 kg noted when drinking water levels were occurs as sulfides, arsenides, child and 70 kg adult were based on an 0.200 mg/l or lees. Using 0.200 mg/l as a antimonides, and oxldcs or silicates. animal study (Whagner. 1973. Effects of NOAEL, an uncertainly factor of 2 based The pure metal is very low in aolubllity. Dietary Nickel on Enzyme Activities and upon a human study with no adveree Nickel salts and many nickel Mineral Content in Rats. Toxicol. Appl. effects noted and consumptlon of 2 litere compounds, however, are soluble. In the Pharmacol. 25323-331). From NOAEL of water per day, a provisional AADl of aquatic environment, nickel is most of 10 mg Ni/kg/day based on effects on 0.10 mg/l was determined. Data on likely to occur as a divalent catlon and weight. hematologic paritmeters and human exposure were not factored In may often absorb to or complex with cytochrome oxidase activity in ruts the AADI because the calculatlona were minera: or organic compounds. following 0 week oral ingestion, with an based upon an epldemlological study In The maJor use of nickel la in the uncertainty factor of 100, assuming which exposure via other sources were manufacture of stalnless steel, nickel- consumption of 1 liler (10 kg child] or 2 necessarily taken into consideration. chrome resistance wire and in alloys for liters (70 kg adult) of water per dey. 10- The only molybdenum compound that electronic and space appllcations. day values [or a child and an adult of 1.0 has been shown to produce tumors in Analytical Methods. Ans I y I ical mg N1/1 and 3.5 rng NI/I. respectively, animals Is an lnorganlc plgment which method9 available for anaylzlng total were calculated.

s-014999 00?7(orxl2-u0v-85-1523: 19) F4701 rev. 8-14-85 46978 Federal Register / Vol. 60, No. 219 / Wednesday, November 13, 1885 / Proposed Mes

A provisional AADI was calculated carcinogenic in rats and mice. Data are and inductively coupled plasma atomic based upon a two-year feeding study in not available concerning the potential emission spectrometry techniques. which rats wore given various doses of carclnogenlc effects of ingested nickel ' Human Expolrum. There are little data nickel in their food [Ambrose, A.M., et compounds in humans. The IARC has on silver levels in air. Silver in ground el. 1978. Long Term Toxicological classified nickel in Group 2Asufficient level aerosols from various U.S. Assessment of Nickel in Rats and Dogs, evidence for carcinogenicily in animals locations was found to range from 0.W I. Food Sci. Technol. 13:181-187). Baaed and limited evidence for carcinogenicity to 4.3 ng/m? generally ranging around 1 on a number of paremeters (body in humans. This assessment was based ng/m? Assuming a ventilation rate of 20 weight. organ-to-body weight ratios, upon inhalation exposure. Nickel has m'/day for the adult male. reaplratory hematologic values, gross and histologic been classified in EPAs Group Bi, intake at levels of 1 ng/m* would be pathology), this study revealed a according lo EPA's Proposed Guidelines approximately 0.02 pg/day. NOAEL of 5 mg Ni/kg day. A for Carcinogen Risk Assessment, based The silver content of various foods disadvantage of this study is that nickel upon the subsulfide and carbonyl has been reported to range from

F4701 rev. 8-14-65 Federal Reglolor 1 Vol. No. 219 1 Wednesday. November 13, 1905 1 Propoaed Rules 48879 60, - 1935. Clinical Spectroscopy. Seventy The only adverse effect from exposure Annlylical Methods. Annlytical Cases of Cenerallted Argyrosis to silver is argyria, whlch does not methods available for analyzing bulfale Followins Organic and Colloidal Sllver impair the functioning of the body or in drinking water include the Medication. J. Am. Med. Assoc. other physiological problems. Thus, turbidimetric and autornntcd 104:1387-13w); Blumberg, H. and T.N, argyria is considered e cosmetic effect colorimetric techniques. Carey. 1934. Agytemla: Detection of and not an adverse health effect and an Itealth Effectr. The only ndvmc Unsuspected and Obscure Argyria by RMCL is not proposed. effects in animds and hum8nr notcd the Spectrographic Denionstration of Question for Comment: from exposure to high, levels of .qulfiite High Blood Silver. J. Am. Med. Assoc. 1. Is it appropriate to consider argyria are diarrhea nnd dchydriition. Solulile 103:1521-1524; and East, et el. 1980. to be a cosmetic effect or is there sulfate salts are nhqnrbd from the Sllver Retention, Total Body Silver and evidence that argyria is an adverse inlestlne and dislri',uted Ihrouhnout Ihe Tissue Silver Concentration in Argyria health effect? Should an RMCL be hody. with large doses hing Associated with Exposure to an Anti- proposed for silver? Should a secondiiry incompletely iilsorbed. renulling ifl smoking Retnedy Containing Silver regulation be proposed for silver? cathartic effects. Suhte in continuously Acetate. Clin. Exp. Dennatol. 5:305-311). excreted in the urine. Calculations were carrled out to e. Sulfate In humena. the concern in for trunnicnt determine the level of silver in drinking Sulfate (SO+-)is a divalent anion situiitions HR individuals will imornr! water, apportioned over a lifotime, found in almost all natural waters. It Hcclimated to high levcln of sulfrite in H which would not result in argyria. The also occurs freqiiently in rainfall. short period of time rind diiirrhcii iintl average AUI of the calculations from the particulerly from air masses of dehydration do not occur iiftcr the Lnitiul 3 studies was determined to be 182 pg/ metropolitan areas where sulfate is acclimation period. inftrntn Hppeiir to be day (average of 108 pglday and 188 pg/ released from combustion of fossil fuels. more sennitivc to sulfiite thiin adults. day). This was calculated by An important terrestrial source is with sever81 cnses of diarrhcn and standardizing the observed body weight evaporite sediment, from which gastroenteritin reported in infante to the 70 kg adult and multiplying this by magnesium, sodium and calcium sulfate consuming formula containing sulfete et the estimated total dose necessary to may be leached. Metallic sulfides such levels ranging from 630-1150 mg/l. cause argyria and apportioning this over as iron pyrites are found in both In areas of the country with high a lifetime (70years). An uncertainly sedimentary and igneous rocks. Sulfalos sulfate conce~itrationsin their drinking factor of two was used Instead of the are released through oxidation in the water supplies, no adverse health effects standard 10-fold uncertainty factor for weathering process. Household waste in older children and adults have been the following reasons: the I&fold Including detergents add sulfate to associeted with exposure to sulfate over uncertainty factor is applied to humans sewage. Industrial effluents from lifetime exposure. In addition. to account for possible sensitive tanneries. steel mills, sulfate-pulp milis, insufficient toxicological data are lndividuals in the general population. and textile plants are other significant avaiiabie to calculate an AADI based The ntudies used in the AD1 calculations sources to surface water. upon short-term effects in adults or involved sensitive individuals and thus Human Exposure. Data on levels of infants. Thus. a provisional AADI will en uncertainty factor less than 10 is sulfate in the ambient air are avaihble not be ca~culatedfor sulfate. Instead. a warranted. In addition, the AD1 from EPAs Office of Air Quality guidance level of 400 mg/l. to protect calculations are extremely conservative Planning and standard^. A summary of infants. way derived based upon cnse because the estimated dose which atmospheric concentrations (1975)for histories which suggest thnt parents caused argyria in 2 to 3 years is being selected locations in the U.S. is should not use water from wells with apportioned over a lifetime of 70 years. presented below. sulfate concentrations greater than 400 An uncertainty factor lese \hap 10 would to 500 mg/i for preparation of infant be sufficiently protective in this formula. instance. Consumption of 2 liters Concsntrrtm so, of ___.'ry!? _.__ In addition. 250 mg/l is presented as a water per day was factored in, resulting 1 yy 1 I Mmp(ar i M~II- guidance level based upon aesthetic in a provisional AADI of 0.090 mg/l. I IC mean, mum considerations. This value would serve There is no evidence that exposure to I to limit the intake and protect the high C.ldm~IOrkIand) ...... , .... silver results in mutagenic or Oh9(CTrmb) ...... risk population (infants). carcinogenic effects. The IARC have not The current EPA secondary drinking classified silver for potential water standerd for sulfate is 250 mg/i carcinogenicity. Silver has been baeed upon aesthetic effects. The WlfO classified in EPAe Group D, according Data were not available on the guidline for sulfate is 400 mg/I based to EPA's Proposed Guidelines for occurrence of sulfate in foods. upon taste considerationa. 'I'he U.S. Carcinogen Risk Aeeessment based The CWSS. conducted in 1970. Army has recommended limits for upon inadequate data in animals and examined 909 drlnklng water supplies in sulfate of 300 or 100 rng/l. based upon humans. the U.S. Levels of sulfate were reported personnel who consume up to 15 liters of The current MCL for silver, under the to range from c1 to 770 mg/l water per day (100 mg/l] end thosc who National Interim Prlmary Drirking (median=4.6 mg/l). Of the sampled consume up to 5 litern of water per day Water Regulations. le 0.05 mg/l. This water supplies. 3 percent had (300 mg/l) (Scofieid. R. and tlsieh. D. level WES based upon one gram of silver concentrations exceeding 250 mg/l. Criteria and Recommend,ations for resulting in argyria. EPA's ambient Analysis of the internlate carrier water Standards for Sulfate in Mililnry Field water qiiality crlte.-la for silver (U.S. supply systems (1975)involved Water Supplies. Univ. of Calif.). EPA. 1980. Water Guality Criteria for examination of e25 finished drinking An RMCL and primary drinking watvr Silver. EPA 44O/WW71)le 0.050 mg/l, water supplies. in 3.4 percent of the re ulations will not be developad for in ogreement with the NIPDWR. Tho samplod rystems, levels of sulfate suffalo 8s there are not sufficient dah irt WHO has not set a guideline for silver exceeded 250 mg/l. The maximum the prasent time on which to set a level' in drinking water. measured concentration was 978 mg/l. for health protection. tiowever,

s-074999 0079(Mn12-NOV-~5-t5:23:24) F4701 rev. 6-14-05 468co Federal Pe$ster / Vol. 50, No. 219 / Wednesday, November 13, 1985 / Proposed Rules exposure lo sulfate at high levels does Pressure Ind High Sodium Levels in the basis for AHAs recommended level of present a health concern for transient Public Drinking Water. 32:300-302; Ibid. sodium was a nutritionally adequate exposure situations and EPA will 1979. 34:187-203). These investigators diet requiring 500 mg sodium per dtly. Of reconsider an RMCL in the future based compared blood pressure distributions the 500 mg,440 mg would be naturally upon nc!w data and research results, as among tenth graders in two occurring in food. An additional 80 mg availabte. Massachusetts communities exposed to would be from non-nutritional intake Qiie-lion for Comment: low (8 mg/l) and high (107 mg/l) levels such as drugs, water. and incidential 1. It in appropriate to derive an of sodiitm in drinking water. Students intake sources. adviaary lor aultate based upon the high living in the hi&h-sodium community In 1878. the National Interim Primary rink popiiintiun or should an RMCL he exhibited higher blood pressures than deveiripcd? Drinking Water Regulations did not their counterparts in the low-sodium contain an VCL for sodium because the 7. Sotliiim community. In the Netherlands (Hofmcin, available data did not support any et el. 1980. lncreased Blood Pressure in particular level of sodium in drinking Sodium (ntomic number 11, atomic School Childrtn Related to High Sodium wcight Z2.W) is a light silvery-whlte water. Ir lieu of the absence of an MCL Levels in Drinking Water. j. Epidemiol. for sodium, EPA supported the AHA'S nlknli mctd thut composes 2.38 percent Comm. Hlth. 34:17+181). a study (hy weight) of the earth's crust. Sodium reported flndings which supported the recommended level of 20 mg sodlum/l in does not occur nn the free clement in hypotheaia that sodium intake drinking water. In 1980. EPA amended niiturc! :)ut in tho form of helldes. influences blood pressure. the Nationol Interim Primary Drinking nilicaten. und cnrbonetes. Sodium Is tho Various epidemiologic studies that Water Regulations. requiring communily principii1 cation in the hydrosphero. It is failed to confirm an association between water systems to monitor and report derived geulogically lrom the leachine of drinklng water sodium and blood sodium levels in finished drinklng water. Jurfnce rlnd underground deposits of pressure also have been reported EPA is not proposing en RMCL for rnltn (c.R.,nodium chloride) and from the (Pomrehn. et el. 1983. Community sodium due to insufficient data showing d, :ompodition of sodium aluminum Differences in Blood Pressure Levela an aepociation between sodium in silicates nnd hilar minerals. and Drinking Water Sodium. Am. 1. drinking waler and hypertension in the Anolyticol Methods. Annlytical Epidemiol. 118:60-71; Punsar, et al. 1975. general population and because of the methods for analyzing sodium in Coronary Heart Disease and Drinking normally minor con!ribution of drinking drinking wnler include the direct Water. 1. Chron. Die. 28259-287: water to the total dietbry intake of aspiretion atomic absorption, furnace Bierenbaum. et el. 1975. Possible Toxic sodium. EPA is suggesting a guidance atomic ubsorption and flame Water Factor in Coronary Heart level for sodium of 20 mg/l in drinking photometry. Disease. Lancet. 1:1008.1010; water for the high risk population as Iiutnon Exposure. While there is I lallenbeck, et el. 1981. High Sodium in recommended by the A: iA, since considernble information on the sodium Drinking Water and Total Sodium urinking water meeting this goal would content ol foods, few studies are Intake cn Blood Prensure. Am. J, not present a sodium-related hazaid to availabie of total daily sodium-ion Epidemiol. 114:817-826 Fausl, 1982. those segments of the population intake for heolty adults. Data that have Effects of Drinking Water and Total thought to be at high risk (e.g., been reported arc based on Sodium Intake on Blood Pressure. Am. J. individitala with genetic predisposition measurement of sodium excretion in Clin. Nutr. 35:1459-1487: Armstrong. et to hypertension. pregnant women. urine over 12 and 24 hour periods. al. 1982. Water Sodium and Blood hypertensive patients). EPA will Reported mean hour levels range Pressure in Rural School Children. Arch. reconsidered the development of an from 1,600 to 9.800 mg. A recent estimate Environ. Hlth. 37:235-245). Willett RMCL for sodium if additional &:a for infants is 89 to 92 mg/kg/day. assessed epidemiologic data relating to become available. A secondary The sodium ion is a major constituent the hypothesis that sodium in drinking standard based upon aesthetic effects of natural waters. Human activities also water causes a clinically significant will be prepared for sodium. contribute sodium to water supplies, elevation of blood pressura among Questions for Comment: primorily through the use of sodium school children in Massachusetts and chloride os a deicing agent. and the use concluded that the data should be 1. Are there sufficient data available of washing products. A survey of 2,100 interpreted with extreme caution (1981. to develop an RMCL instead of a health finished wnter supplies was conducted Drinking Water Sodium and Blood advisory for sodium in drinking water? from 1W3 to 1988 by the U.S. h!Ac Pressure: A Cautious View of the 2. Does the proposed health advisory Health Service. Levels of sodium ion 'Second Look'. Am. j. Pub. Hlth. 71:729- for sodium provide protection to high were found lo range from 0.4 to 1,800 732). Based on the available studies, it risk populationn? mg/I. Of the supplies hev!ng sodium ion appears that insufficient evidence is concentrations. 42 percent exceeded 20 8. Antimony, Berylliun,. Thallium md available to conclude whether or not Vanadium mg/l. Levels in 5 percent of the supplies sodium in drinking writer causes an were greater than 250 mg/l. In a later elevation of blood pressure in the Antimony, beryllium, thallium and study (1975) of interstate carrier water general population, vanadium were included in the list of supply nystems, sodium ion It has been estimated that food lOCs under consideration for Revised concentrations in 830 systems were accounts for approximately 90 percent Regulations in the ANPRM. Preliminary found to range from c1 to 402 mg/l. A of the daily intake of sodium whereas analysis indicated limited potential for total of 42 percent had levels exceeding drinking water contributes up to the drinking water exposure causing a 20 rng/I: 3 percent had levels greater remaining 10 percent. significant risk from these substances. than ZOO mg/I. In order to afford protection to a Data collection efforts on occurrence/ Iimlth Effects. The first epidemiologic segment of the U.S. population on a human exposure and potential health study of the relationship of sodium in sodium-restricted diet. in 1868. the effects have not yet been completed or, drinking water and blood pressure in the American Heart Association (AHA) these substances and these four lOCs United States was undertaken by recommended a level of 5 mg of sodiam will be considered in later Phases of the Cnlabrese and Tuthill(1977. Elevated per 8 ounces of water or 20 mg/l. The Revised Regulations.

F4701 rev. 8-14-85 -_ Federal Reglster I Vol. 50, No. 219 1 Wodneeday, November 13, 1985 I Proposed Rules 46981 8. Zinc avallable. (2) exposure to any of these are proposed are summnrized in Tuble Zinc was also included in the list of SOCe "moy have any adverse effect 15. lOCs under consideration for Revised upon the health of persons" and. (3) they Regulatiane in the ANPRM. The Agency occur or are likely to occur in drinking A. Avoilobility of Analytical Methods has not identified any adverse heoith water. EPA approved analytical mcthods HI(: effects that are caused by zinc. The NAS Below ere: (I)A summary of the aveilable for most of the SOCe being Safe Drinking Water Committee aveilability of analytical methods, and considered in this RMCL proposui. (Drinking Water and Health, 1977. Vol. (2) summaries per SOC of analytical These methods may involve gus I) concluded that, "zinc is en essential methods, occurrencelexposure and chromatography (GC). gas nutrient for humans. There le evidence toxicoiogy. chromalogrophy/mosr spectrometry of borderline deficiencies of the clement (CG/MS). and arid high prcavure liquid in children in the United States as well In the MCL proposal, EPA will chromatography (tipLC). as in other parts of the world . . . .The propose the analytical methods thet Purge and trap methods arc Hvnilrilh possibility of detrimental health effccta have been determined to be for those SOCe that arc voitiliie. 'I'htrnv arising from zinc consumed in food and economically and technologically compounds which are methylene drinking water le extremely remote." feasible. In the toxicology discussion for chloride extractable mHy be iInHiyzl!tl Thus. EPA has concluded thet each SOC, the acute and chronic toxic by 800 series mcthods (Le.. EPA rncthtrris potentid adverse health effects will not effects of exposure along with any for anoiysis of priority pollutants). 01iwi ariso from zinc in diinkinp water and carcinogenicity data are aummtrrized. compounds may be eniilyzed by newr this compound is not being considered When dote ere available, adiusted methods developed recently but not >1!1 for regulation at the present time. acceptable daily intakes (AADls) based approved by the Agency. VIII. Synlhetlc Organic Chemicals: on non-carcinogenic effccts are Since a number of the 800 ecrir:s RMCL's determined for long term exposure to the methods have been recently applied to SOCs. In eddition, short-term cxpoRure drinking water snrnplee in addition lo The ANPRM (48 FR 45sO2) listed e waste effluent samples. multi-lirlmra tory total of 43 synthetic organic chemicels is also considered and short-term assessments are determined for I-day method validation data are iivaililble lor (SOCa) that were being considered for many of the compounds in this proposiil. inclusion in the NPDWR. Inclusion of and 10-day exposures. These aaseesments are provided for both SOCs Multi-laboratory date from performencc! specific SOCs on the list was based evaluation studies are also iivailrihle for upon thc occurrence or potential for which RMCLs are proposed and for those SOCs for which regulations do not some compounds, using reagent water. occurrence of the SOC in drinking water For the newer methods, only single and the potential health effects of appear lo be appropriate. A summary of heolth-related guidelines prepared by laboratory. single operator performance exposure to that SOC. Inclusion in the data are available. list did not necessarily mean thet other groups and organizations is reguhtions would be developed for the provided for each SOC. Values that SOC but that those were the SOCs have been calculated by the World TABLE12.-PROWSEO RMCL'S AND AADI'S currently heing considered; other SOCs Health Organizetion (WHO), the FOR SX'S PROPOSED FOR RECUUTION not listed could also be considered and Nationnl Acedemy of Sciencies (NASI. included in the NPDWR. Selection of EPA'a Office of Water Regulations and 0,". SOCs for the NPDWR le based upon an Standards (OM'RS. Water Quality analysis of occurrence and potential Criteria) and EPA's Office of Pesticide occurrence, the significance of potentiel Programs (OPP) have been included. In human exposure, essocioted health several instances, these values differ effects of exposure and other pertinent from the proposed AADls. This is due to factors. several factors, including the use of EPA is today proposing to regulate 26 different uncertainty factors, and of the 43 SOCe in the ANPRM: five of reinterpretation of data and varying the SOCs were detennincd to be asmnptione. In addition, new date may inappropriete for regulation due to such have become available over the years factors os lack of potential occurrence in which has resulted in the derivation of drinking water. lack of actual an AADl which differs from olaer occurrence data, or insufficfent health calculated values. Taste and odor effects data. Short- and longer-term threshold values also have beeii tnxicology assessments have been included for certain cont minents. developed for those five SOCs for which regulations ere not appropriate: these A summary of the RMCLs and AADIs assessments may be converted to formal is presented in Table 12. Risk estimates Health Advisories. In addition, 12 SOCs have been projected using calculation of the 43 SOCr will be reconsidered in models for SOCs for which data are later phases of the Revised Regulation available and are summarized in Table develnpment as additional data become 12. Short-term assessments and available (see Table 1). provisional AADls for SOCs for which RMCLe are proposed for 28 SOCs for RMCLe are not proposed are which the Administrator has determined summarized in Table 14 and bhort-term that: (I) Analytical methods are aasessmenta for SOCs for whish RMCLs

S-074999 OOR I(OS)( 12-NOV-RS- I S:2J: IO) F4701 rev. 6-14-85 46982 Federal Register / Vol. 50, No. 219 / Wedneedey, November 13, 1985 / kopoeed Rule8

TABLE 13.- RISK ESTIMATESFOR SOC'S FOR WHICH DATAWERE A,VAILAELE alternate procedure is required to develop a nuiteble analytical method for the determination of acrylamlda in EPA CI.ruhcr#n drinking water. Additional research is required on the development of multi- contaminant monitoring methods for the AQllrm6 ...... 8' SOCs. including the une of capillary CC Ahh8a ...... 8' and capillary GC/MS techniques. olrodu*...... 8' DBCP ...... 8' ...... C TABLE 16.-ANALWlCAL METHOOSFOR ...... 8' ...... 0 11 8' 1 UsmDd' ...... 8' - ...... 00104 8' 000065 8' Asrl(.m6 ...... I No 0lnnOuez.d €PA m*hod...... 0 02 054 8' AlvNor ...... socnn( e.trubon OC. 1lnd.m...... 0 om 0 555 C Alb.m ...... HLPC; 531 MWobmmw...... NA 2 35 C AW uno...... socnn( .NMon GC:610 PC8r ...... o wro 0 16 8' .. soc~ncemm mc. w2...... NA C .. sobmt nb- GC. we 0 03 8' Socrmc er~Y(mOtlMS 625 CaIcJllodpI EPA'r oI(*r 04 P.raa6. Roqura. Oecp ...... bo. 6 Trg OC. 502.1. 'TnlUslO . '! 4.01 Trap GCIMS. 524. Nofa -NA ,No( -. 01. rd trrcrr1.2.bctUor. 4.0.h Trrp GC;502 1. -. -. TAELE 14.- SHORT-TERMASSESSMENTS AN0 PROVISIONAL MDl'S FOR SOC'S FOR WHICH traml,Z.acHaoechlla*.....Pw~ h Trg GC: 524 ~.acMaoDenzam...... Pug. h lrg GC: (io31 RMCLs ARE NOT PROPOSEO 4.p h Trap GCIMS. 524 rn-~ ...... bga 6 Trap OC, 5031. 4.0.h Trap GCIMS. 524. soc td.l'!!% ..,. bo. L lrg oc: 502 1. child MJI 0 4.01 h Trg Gc. 01. Rrpe 6 Trap GcIMS. 624 ...... NA NA NA NA 10 75 1 4.0.h Trap GCIMS. 524 31.2 n.8 31.2 NA ...... ! Darlmbon GC 615. .._.1 Pwge 6 Trap Gc: 502.). a 3.5 '1 '3.5 '35 i Endn...... o or 0.005 0 02 0.0016 Enm...... w emKbQI Gc:808. wen...... 0.05 0.17 0.05 0.11 0 029 ! ken Ilvc9on Gc Puge h Trw Gc. 02. sotven( WybQI Gc. 806 socrem WMon GCIUS. 625 MUMa ...... -1 mmGC, n12. No(..-NA. No( N- wne...... socnn( amaclm oc;a08 M- M- ...... socrenl e.trulmn GC;808 TABLE15.-DRAFT SHORT-TERM AS~ESSMENTSFOR WsFOR WHICH RMCU ARE PROPOSE0 M~oben?am...... 14.0. 6 Trw OC; 5031 Pug0 h Trap Gc:MS. 524. ParM1oropllsno( ...... sahnl emm Gc. 604 rgl0 -- 1- SoCranc GGMS. A6n u*ld PCBr' PC8.1242...... i !~WWWII ~NY(IO(IGC: 6~3 s;mslae ...... GC;e18 5.25 03 10 002 ow 1 bgeh Trap GC: 503.1. 52 5 15 52 5 NA NA T0)usne ...... I Puge h Trw GC:02. .0.042 0012 0 042 OP12 0042 Tcmaphene~...... 1 em~onGC: o.oin NA NA 005 oin 2.4.5-TP ...... IIbnvimahOn GC: 615. NA 0003 0 22 NA NA 2.3.r.c~c~o...... sccrem sltrroan ccius. 14 10 35 10 35 0.7 0 05 0 17 NA NA Xviaun: para-. mar.. NA 008 0 31 NA NA ulb. NA NA NA 60 31 2 3.15 03 11 NA NA NA Om 0 027 NA NA NA 0 lb 05 0022 007e 72 21 12 NA NA NA 0 01 0 035 NA NA NA NA NA NA NA NA 12 43 OW3 012 22 4 20 ro NA NA Mgnochknobenrene ._ ...... NA NA in 63 8 305 NA NA NA NA NA PmluMorophencl...... 1 0 3.5 03 11 NA NA B. Proposed RMCb Swam ...... zr 94.5 20 ro 20 70 To*ene ...... in 63 6 21 NA NA 1. Acrylamide 2.4.STP ...... NA NA 02 0 75 NA NA Tor.ghene ...... 0.5 1.75 ow 028 NA NA Acrylamide (propenamide. CAS *7% WaM. 1.2.achla ...... 2.7 8.5 10 35 10 35 xlcens ...... 12 42 NA NA 7n 27 3 OBI) is used primarily as a starting material for the manufacture of water tao*nml$nor soluble polymers employed to enhance oil and water recovery from welle. as flocculants in potable and weete water treatment. food processing. in paper Table 18 lists the analytical methode literature ueing bromination of the making, dye application, adhesives. soil presently available for the SOCe. There double bond followed by gas conditioners and permanent press ie no standardized EPA method for chromatography analynie ueing an fabrics. Acrylamide is extremely soluble acrylamlde. The analyals of ecrylamlde electror! capture detectoi Further in water (2.15 x 10rmg/ll and is soluble has been rcported in Be puhliehed research on this approach or an in alcohol, ether and acetone.

S-074999 OO82(05k 12-NOV-85- IS:25:12) F4701 rev. 6-14-65 Federe1 Rdster I Vol. 50, No, 219 / Wednesday, November 13. 1985 / Proposed Rules 46W

_A Analytical Methoda. No EPA Acrylamide. Toxicol. Appl. Pharmacol. without microsomal activetion) or in the approved analytical method is presently 6&86-ioi).While measuring the rate of hepatocyte culture DNA repair assav available for acrylamide. although a retrograde axonal tramport of iodinated (Bull, et el. 1984. Carcinogenic Effects of research method is now available. nerve growth factor in rats treated with Acrylamide in Sencar and A/J mice. Human Exposure. Acrylamide single intraperitoneal doses. the authors Cancer Res. 44:107-111: Miller, et ai. monomer is a common contaminant of showed that significant inhibition of 1984. Lack of Cenotoxicity of polyacrylamide used in food production transport ensued at or above doses of 25 Acrylamide IJsing the Ilepatocyte and as a coagulant aid in the water mg/kg, while no significant changes Primary Culture (tIPC)/DNA Repair treatment process. Polyacrylamide may were seen at or below 15 mg/kg. The 1- Test. Abstract No. 138. Presented at the be contaminated with up to 0.05 percent day assessments were derived by 1984 meeting of the Society of acrylamide monomer, which upon applying an uncertainty factor of 100 to Toxicology, Atlant;i. GA. The leaching, could yield a 0.5 pg/day intake the NOAEL of 15 mg/kg. yielding a Toxicologist 4(1):35). Chromosome by humans from drinking water alone. value for the 10 kg child of 1.5 ng/I aberrations were noted in the Technical grades of polyacrylamide, which assumes consumption of 1 liter of spermatogonia of mice exposed to 75 having higher levels of acrylamide water per day and a value for the 70 kg mg/kg/day in the diet for 2-3 weeks. but monomer, are used in drilling new adult of 5.25 mg/l which assumes bone marrow cells were not affected potable water wells. These acrylamide consumption of 2 liters of water per day. (Shireishi. Y. 1978. Chromosome residues may remain in the surrounding The I(rday assessments were derived Aberrations Induced by Monomeric soils. Technical grades of from a NOAEL identified in a drinking Acrylamide in Bone Marrow and Germ polyacrylamide are used in mine water study (Gortinski. et el. 1979. Cells of Mice. Mut. Res. 52313424). management and reclamation and have Re~ult~of Polatability (12-day) and Both the marrow cells and been reported to have contaminated Tolerance (21-day)Studies on spermatogonia showed a striking local water supplies with acrylamide Acrylamide Monomer Administered in decrease in mitotic index following a moncnier. No monitoring data are the Drinking Water of Rats. Dow single intraperitoneal dose of 50 to 150 available to describe the frequency or Chemical Company. Unpublished mg/kg. level of human exposure via food, air or report). The monomer was administered Only one published study (Bull, et el. drinking water. While monitoring for in drinking water at levels of 0.1.3. 10 1984. Carcinogenic Effect of Acrylamide acrylamide has been limited, the or 30 mg/kR bw/day for 21 consecutive in Sencar and Strain A/J .Mi.-.. Cancer potential for occurrence in drinking days. Based. upon-hictological Research. 44:107-111)'is'a~ailablewhich water exists because of its use e8 an examination of peripheral nerves ~t addresses the carcinogenic effects of additive in drinking water treatment both the light and electron microscopic acrylamide. This study showed that processes. levels. it was determined that effects acrylamide acted as a tumor initiator in Health Effects. The principal toxic occurred at the two higher doses. while the skin of the female Sencar mouse effect from exposure to acrylamide no significant changes were apparent at when administered orally. topically or (monomer) over any duration of time the two lower doses. A NOAEL of 3 mg/ by intraperitoneal injection. Acrylamide and by any route in animals is kg/day thus was identified. The 10-tiay also increased the yield of lung peripheral neuropathy. Subchronic values were derived by applying an adenomas in strain A/j mice when given studies have demonstrated a variety of uncertainty faclor of 100 to the NOAEL orally. In addition. preliminary data effects. including atrophy of skeletal yielding a level of 0.3 mg/l for the 10 kg from another study show that muscles in the hind quarters. testicular child which assumed consumption of 1 acrylamide causes a significant increase atrophy and weakness in the limbs. liter of water per day and a level of 1.05 in trimor incidences at several sites in Long-term exposure to acrylamide also mg/l for the io kg adult which asstimes both male and female rets exposed to has been shown to result in neurotoxic consumptic-n of 2 liters of water per day. acrylamide in their drinking water. A effects and weakness in the hind 'fie study scleclcd for the derivalion quantitative risk assessment has not quarters. Case reports suggest that of a provisional AADI was a subchronic been performed on acrylamide, pending similar effects occur in the human study in wbich rats were administered submission of the data to the Agency for following cxposure via the dermal, oral daily doses of 0. 0.05.0.2. 1:s or 20 mg/ review. Acrylamide has been classified or inhalation routes. Recent evidence kg in their drinking water (Burch. et al. in EPA's Group 82. according to EPA's shows that acrylamide in carcinogenic 1980. 1. Environ. Path Tox. 4:157-182). Proposed Guidelines for Carcinogen in mice and rats when administered by The parameters measured were gross Risk Asscssment based upon the one of several routes: oral, topical or neuropathy as observed by !he limb positive results in studies in mice and intraperitoneal. splaying method. ultras:mctural rats. No adequate dose-response data examination of peripheral motor nerves. The data strongly suggest that representing the oral route of exposure hematology. clinical chemisIry and body acrylamide monomer ir carcinogenic in are available from which to develop and organ weights. On the basis of the animal species. Because of these short-' !nassessments. However. in the most sensitive measure of toxicity. Ihe potential adverse health effects and the light of substantial chemical disposition unltrastructural examination, it was fact that acrylamide is likely to be evidence showing that acrylamide is concluded that 0.2 mR/kR WAS the occurring in water supplies. due to its absorbed rapidly end completely by N0AT.L Using this NOAEL an use as an additive in the drinking wdtcr virtually any route of exposure. it is uncertainty fac:or of 100 based upon an treatment process. EPA is proposing to considcred acceptable to use data animal study with the NOAEL regulate this contorninant. The RMCL generated Iollowing exposure via these identified. an uncertainty factor of 10 to will be hosed upon carcinogenic effrcts other routes. The 1-day assessments convert from subchronic to chronic and an RStCI. of zero is proposed. were derived from a NOAEL of 15 mg/ exposure and consumption of 2 liters of 2. Alachlor kg identified in an animal study (Miller. wakr per day. R provisional AADl 111 et el. 1983. Altered Retrograde Axonal 0.007 mg/I was determined. Alachlor 112-chloro-2'ti' diethyl-n- Transporl of Nerve Growth Factor After Acrylamide did not elicit mutagenic fmcthoxymrth~I] iiwt;iniliile);CAS = Single and Repeated Doaes of activity in the Amps test [both with arid tSS724304l is ii hrrtikidt- ::sed primarily

F4701 rev. 614-AS 48984 Federal Register / Vol. 50, No. 219 / Wednesday, November 13, 1985 1 Proposed Rules on corn and soybeaim Alechlor is (rat LDw=0.93 glkg), dermal (rebbit at 150 mglkglday when aluchlor was rliRhtly soluble in water and can enter LDs0=13.3 g/kg), or inhalation (rabblt administered to rats on dny e through 15 water systems by runoff from L60>5.1 ml/l) routes of exposure of gestation. Using the NOAEL of 150 agricultural fields into surface water or (Monsanto, 1978a. Acute Oral Rat, mg/kg/day. a 10 day health advisory for by lenching downward through sol1 to Acute Dermal Rabbit. Unpublished a 10 kg child is 15 mg/l and for a 70 kg ground welcr. study received 1978 CDL241273; adult is 52.5 mg/l. Analytit:ol hlethods. Anulytlcal Monsanto. 1981~.Acute Inhalation I.Dw Alachlor feeding studies have methods uvailable for analyzing Rat. Unpublished study received 1881; demonstrated oncogenic elfects wh!ch nlnchlor in drinking water Include the CDL248053). Although alachlor Is a skin include lung tumors in mlcc. and nolvcnt extreclion-RHs chromatography sensitizer and causes ocular lesions stomach, thyroid, and naml turbinate Icchniqiie. upon chronic exposure, the technical tumor8 in rats. Two chronic fecding ffiimorr Exposum. Alachlor la product hne only slight skin and eye ntudies were conducted in the Long rcRistered prlmnrily for use on beans, irritatlon potential after an acute Evans straln of rat with alechlor. In the rnrn, cotlon, pennuts. pens, sorghum, exposure (Monsanto. 1978b. Primary Eye first study, the technical material was Hoybcnnn. sunflowers und woody and Primary Dermal Irritation Rabbit. slabllized with epichlorohbdrln during orniimcntuls. Tolerances for alachlor Unpublished study received 1978 the first year of the study (Daly. 1981b. have bccn established for eggs. milk, CDL241273; Monsanto. 1984a. Dermal An Eighteen-Month Chronic Feeding Hnd the ht, meat and meut bpproducts Sensitization Guinea PiR. Unpublished Study of Alachlor In Mice. Unpublished of cutfle,gotile, hogs, horses. poultry and study received 1984: CDL:25277?’. study received 1981, CDLO7IBB-A, nhccp. A two year rat feeding study in the 070169) and fed to 50 animals/sex nt . Estimntcn of dletsry exposure to Long-Evan8 strain of rat showed alochlor have been calculated based dose levels of 14,42. and 128 mg/kg/ alachlor to be toxic at all doses tested; day. During the second year of thin upon the cbtimated level of each food 14.0. 42.0 and 126.0 mg/kg/day item for which a tolerance has been set study, alachlor stabilized with (Monsanto. 1982. Environmental Fate of epoxidized soybean oil wan the test in the lypical diet. These calculationn Microencapsulated Alachlor: Vol. I and suggest a total dietary exposure of material throughout the study. 11. Unpublished study received 1982. Dose-related responses were 4 x 10- mg/kg/day. CDL070841). The principal toxic effects There arc no data to indicate the observed for tumors of the nasal of concern were hcptatotoxicity trnd an turbinate of both sexes for the mid and presence or absence of alachlor in ocular lesion. referred to as the uveal ambient air at production and use sites, degeneration syndrome (UDS). UDS is high doses. Also, increases were or in urban air. characterized in its mildest form by free observed in the incidence of malignant Five regional studies conducted in the floating irideal and chorodial pigment in stomach tumors (described by the midwestern United Stoles provide the ocular chamber and pigment authors 88 neoplasms pluripotent in evidence of the occurrence of alachlor in deposition on the cornea and lens. In its ability to form a mixed surface end ground water. During the most severe form, the syndrome is carcinomasarcoma-type tumor) in the spring and slimmer of 1981, one study characterized by bilateral degeneration high dose of both sexes (p <0.001). In showed alachlor to be present in 80 of the iris and diminution of the size of addition, thyroid follicular tumors percent of the samples (293) taken from the ocular globe with secondary total (adenomas plus carcinomas) appeared 12 different streams. The maximum cataract formation. to increase in both sexes at the high- concentration observed was 104 pg/l. A follow-up two-year feeding study in dosage level with the increase being During 1982-1884, alachlor WES aloo the aame straln of rat was conducted at significant (p

S-074999 ~8~05)cI2-NOV-~5-I5:25:17) Federal Reglster / Vol. 60, No. 219 / Wedneaday, November 13, 1885 I Proposed Rule8 40885 - --- - for the remeinder of the two yeer period. Human Exposure. The dele obteined Given he nature of the primary This study indicetes thet the tumor on levels of aldicerb in food in the U.S. toxicity of aldicerb and its metiiboiitea response observed in the earlier study were insufficient for use in estimating (rapidly-reversible cholinesliwm cannot be explained by the presence of lypicel dietery inteke of aldicerb. ifihibition), the same NOhEi. can he epichlorohydrin in the test materiel and However, e worst-ceae eslimete of used as the basis for the tirrivution of sumeels that partial lifetime exposure dietery intake frxn food resldws on elloweble levels over virtuiiliy uny (epptoximately one-fourth of the raw egricultural commodities could duration of exposure. This NOAEL Iifcspan of the enimals) resulted in e opproach 108 pg/dey for a 70 kg adult (0.125 mg/kg/day) wag idontificd in ii similer tumor incidence 8s e lifetime (1.5 pg/kg/dey). study in which rats were iidniiniatcreti exposure. Residues ere approved for specific doses of aldicerh sulfoxide 111 IIWCIR of O. The IARC have classified elachlor in crops. In e 1982 study of citrus fruit, no 0.125, 0.25, 0.5 or 1.(1 nig/kg I)w or Croup 3 inedequate evidence for detecteble eldicarb residues were found aldicarb sulfone at levels of 0. 0.2.0.6. carcinogenicity in humam and in sny semples of orengcs. One 1.8,5.4 or 18.2 mg/kg bw in the diet for inadequate evidence for carcinogenicity grapefruit sample contained 50 pg/kg periods of 3 or 8 months (C.S. Weil and in animals. This classification wes eldicarb. Aldicarb residues, renging C.P. Carpmler. 1988i1.b.l'emik carried out before the reaults of the from a trece to 470 pg/kg, were sulfoxide. Temik sulfonc. Rcsults of elechlor feeding studies were aveileble. identified in 78 percent of samples of Feeding in the Diet of Rrita for Six Alechlor has been clessified in EPA's potatoes analyzed in 1979. Ninety-four Months end DORRfor Three Months. Group BZ, eccording to EPA's Proposed percent of somples enelyzed in 1980 Mellon Institute Report 31-141 und 31- Guidelines for Risk Assessment, based contained Jetecteble resldues renging 142. EPA Pesticide I'ctition No. gk'O7g8). upon positive results in feeding studies from 50-520 pg/kg. The results of the study dcmonstrtited u In mlco end rets. No deta were sveileble on levels of subslantir I reduction of cholinesterase EPA's Office of Pesticide Programs eldicarb in ambient sir. activity et the three highest dosage has derived esthetes of risk of daily Aldicerb hes been detected in piound levels of both compounds when exposure to elachlor in drinking weter water used as drinking weter. Of the measured immediately after cessation of based upon the incidence of tumors of feeding. A NOAEL of 0.125 mg/kg bw the nesal epithelium, stomach end 8404 semples collected from wells on Long Islend, New York, es of 1981,29 * we8 determined for the more toxic thyroid from en ingestion study In rets. sulfoxide. The estimeted lifetime cancer risk retea percent conteined total aldicarb are shown in Table 13. residues greeter then the detectioa limit From the NOAEL of 0.125 mg/kg/dey. The nveileble deta indicbte that of 1 pg/l. Weh~neer a farm in northern e provisiond AADl of 0.042 mg/l for the elechlor has cer:inogenic effects in California showed eldicarb residues of 70 kg sdult cen be derived by applying enimels. Alechlor has been detected in up to 24 pg/l. Three out of nine wel!cr an uncertainty fector of 100, iippropriate public weter systems and is highly sampled in southern New Jersey for me with a NOAEL derived from mobile in the environment. Thus. EPA is conteined aldicarb concentrations of 3, enimal date. and assuming consumption proposing to regulete this contaminant 4, end 50 pg/k a weter sample collected of 2 liters of water per day. The end an RMCL will be based upon near citrus groves in Floride was provisional AADl (0.042 mg/l) is also carcinogenicity; en RMCL of zero is reported to contain 3.5 pg/I eldicerb. appropriate for use es I-day and 10-day proposed. Data on water samples from walls in assessments for the 70 kg adult. The 1- Wisconsin, Floride, Maine, Virginia end day and 10-dey assessment for the child 3. Aldicarb, Aldicerb Sulfoxide end North Ceroline indicated that mmples (assuming a 10 kg chiid consuming 1 liter Aldicarb Sulfone from approximately 4 percent of the of weter per day) is 0.012 mg/l based Aldicarb (2-methyl-2- wells studied had aldicarb upon the seme study. (me thylthio)propenel-o-((methylamino) concentrations in excess of IO pg/l. Conclusive evidence on the cerbony1)oxime; CAS #115€%-3] also Aldicerb residues elso heve been found mutagenicity of aldicarb is not currently known 8s Temik, is e registered in ground water in New Jersey, Rhode evsilable, elthough the few studies done pesticide used to control insects, mitea Island (recent USCS study), Missouri to date do not suggest mutagenic end nemetodes. Aldicarb's high aqueous and Messechusetts. Aldicarb also has potentiel. Aldicarb has not been shown solubility is one reason thet water been detected in surfece weters. to be carcinogenic in animals. The serves as e pethwey for its movement in HeolfhEffects. Animal studies heve National Cancer Institute (NCI) the environment. Aldicerb is not tightly demonstrated thet eldicerb, 8s well as conducted e bioassay in which rats end bound to either orgenic meteriel or its sulfoxide end sulfone metebolites, mice were fed 2 or 8 ppm eldicarb in the cleys. Although the vepor pressure of ere absorbed readily by mammelian end diet for 103 weeks (0.1 or 0.3 mg/kg. bw. aldicerb is low, eldicerb may enter sir non-memmelien species. The parent respectively) (NCI. 1979. Bioessay of directly during end following compound end its sulfoxide metabolites Aldicarb for Possible Carcinogenicity. epplicetion, spillage, or diaposel. EPA ere potent cholinesterase inhibitors: the NCI-CGTR-13h USHEW PI 1s. estimeted thet 3.5 million pounds of sulfone is substentially less so at Netionel Institutes of Health). The aldicerb were used in 1979. Commercial equivelent doses. Laboretory studies conclusions of this study were that no agriculturel epplicetions account for w) have found thet aldicerb is excreted tumors could be attributed solely to percent of the estimeted ennuel rapidly from the body, primerily via the trldicerb administretion. Two Z-year domestic usege. Aldicerb also is used on urine. feeding studies ir? rats also reported that ornementals (commercial field grown The principel toxic effect of eldicerb eldicerb did not produce e statistically end nursery plentings, greenhouse end its sulfoxide end sti!fol;c significant increese in tumors vihen crops, end potted plants). metabolites is cholinesterase inhibition compared to controls (C.S. Weil and C.P. Analytical Mefhods.Analyticel 8s measured in plesma, eq Lhrocytc end Cerpenter. 1965. Two-year Feeding methods aveileble for enslyzing brein. This inhibition hes been Study of Compound 21149 in the Diet of aldicerb end its degradetion products in demonstrated to be transient in neture, Rets. Unpublished report; C.S. Weil, drinklng weler Include the high pressure when not fetel, due to the spontaneous 1972. Aldicerb (A), Aldicerb Sulfoxide liquid chromatography technique. recovery of the inhibited enzyme. (AsO), Aldicerb Sulfone (AsO,) and a

S-074999 OOSS(OS)( I2-NOV-8J-IJ:2S:19) F4701 rev. 8-19-85 46986 Fe\braI Reglater / Vol. SO, No. 218 I Wednesday, November 13, 1085 / Proposed Rules

1:l Mlxture of AS0:ASO.. Two year 1. Is it approprlete lo propose an relallvely rapid and the compound(s) Fecdlng In the Diet of Rats. Unpublished RMCL for aldlcarb residues to be would not be expected to accumulate report). Aldlcarb has been claeslfled In protective of the 70 kg adult, rather than slgnificently In memmalian tissues EPA's Croup E. accordlng to EPA's tho 10 kg child? The most sensitive end- following repeated exposures. Proposed Culdelinea for Carcinogen point of toxlclty (chollnesterase The principal adverse hcallh effect Risk Aeseanment, bnscd upon negotlve inhlbitlon) Is an acute, rapldly-reverslble occurring following exposure to rcsulte In ncveral anlmal studlee. phenomenon which is the basis for the carbofuran le the rapid inhibillon of The Food and ARrlcuitural derivation of allowable exposure levels cholinesterase aclivlty. The effect has Orgiinlzutlon/Worid I tealth over all durations of exposure. been demonetrated to be transient in OrRaniralion has proposed ADIS for 2. In the allocation of an RMCL for nature. when not fatal, due to the altllcarb rcsldues of 04.001 mg/kg/day aldlcarb residues, It was assumed that spontaneous recovery of the inhibited in 13°F~ end (M.005 mg/ku/day In 1982. drlnklng water could contrlbute 20 enzyme at sltes in the central and Tlie NAS (1977: 1963) proposed an AD1 percent of an Indlvldual's daily exposure peripheral nervoue systems. Other acute of 0.001 mg/kg/day based Labon two- to these realduea. le thla appropriate, in effects on the immune system and blood ycnr fecding studies In rats and dogs Ilght of the potential for elgniflcant parametere have been reported. These. nnd n nuRRcsled-no-adverse-reeponee- exposure via non-water sources for the too, appear to be reverslble once level (SNARL) 017 pg/l using tho same 70 kg adult. but more llmlted potential exposure Is terminated. In addltion. at etudles with en uncertainly factor of for the 10 kg child? doees above those nt which inhlbltlon of 1OOO. The SNARL le protective for a 70 4. Carbofuran cholinesterase is noted. aspennla and kg adult for whom drlnklng walcr testicular degeneration In dogs and contrlbules 20 percent of the daily Carbofuran (2,3-dihydro-2,2-dlmethyl- some minimal decreases in rat pup cxposurc to aldicarb residues. EPA's 7-benzofuranol-methylcarbamale; CAS survlval also have been observed. Ofnce of Pestlclde Programs has * 1563-6&2) le an insectlcide and catabllshed an AD1 of 0.003 mg/kg/day nematocide. EPA eatimated that about A study by FMC Corporation (1977. (46 FR 57047) based upon the same 11 million pounds were used In the U.S. lnduetrlal Hygiene Studies. final report. study used to dcrive the provisional during 1080. Elghty-four percent of the MRI Project No. 423CLB. EPA Acceselon AADI. carbofuran le used on corn. Technical No. 241303) was selected as the basis for Ordinarily, an RMCL Is proposed for carbofuran has an aqueous solubility of the calculation of 1-day assessments for the parent compound. In this case, 700 mg/l and is mobile in water. the 10 kg child and the 70 kg adult. Adult however. the RMCL is proposed for total Analytical Methods. Ana I y Iical male human volunteers were aldicarb residues (the parent compound methods available for analyzing administered a single oral dose of as well as the sulfoxide and eulfone carbofuran in drinking water include the carbofuran shortly after eating degradation products). The reason for solvent extraction-gas chromatography/ breakfast. Of the three doses employed this le that the residues of aldicarb mass spectrometry and the solvent (0.05,O.lOor 0.25 mg/kg bw), only the found most often In water eamplee are extraction-htgh pressure liquid lowest dose was without effect, as Ihe sulfoxide and sulfone, with chromatography techniques. identined by a lack of a statistically and relatively little of the parent compound H 'man Exposun?. Data obtained on biologically siqnificant depression of red being present. In addition. the analytical levels of carbofuran in foods were blood cell cholinesterase activity levels. methodology most commonly used to insufficient for use in estimating typical To the NOAEL of 0.05 mg/kg, an determine aldicarb residueti in water dietary intake levels. However, uncertainty factor of 10 was applied, samples includes oxidation of the carbofuran residues are permitted on consistent with accommodation for residues to the sulfone, followed by several crops. Peanuts from Arkansas intraspecies variability. This resulted in identification/quantification of the have been reported to contain up to 25 a I-day assessment for the 10 kg child of residues as sulfone. Toxicologically, the pg/kg carbofuran. If till crops contained 0.05 mg/l and for the 70 kg adult, 0.18 RMCL Is based upon data from studies the maximum reslduee permitted, the mgll. No adequate dose-response data on the sulfoxide. This is because the dally intake for atlulta would be exist from which the l&day assessment sulfoxide is slightly more potent that the approximately.530 p /day. could be derived. Since, however, the parent compound and slgnificently more No data were avaifahle on levels of end-point of toxicity that le of concern in potent than the sulfone as rin inhibltor of carbofuran In ambient air. this case is a rapidly-reversible, cholinesterase, the end-point of toxicity Carbofuran has been found in ground transient effect, the 1-day assessments Considered to be the moet sensitive water sampleo from New York and for the 10 kg child and the 70 kg adult measure of an effect. Wisconsin at levels of 1-50 pg/l. it also also can serve as the 10-day aaseeement EPA is proposing to regulate this has been detected in ground water in for each individual. contaminant based on its toxicology, three other States. The one-year dietary study in beagle occurrence in water and potentiel HealfhEffects. Like other members of dogs was selected to serve as the basis occurrence in drinking water supplies. the class of carbamate pesticides, for the derivation of the AADI (FMC The RMCL for aldicarb residues is carbofuran is a potent Inhibitor of Corporation, Agricultural Chemical based upon the effcct of cholinesterase cholinesterase. It le expected to be Croup. 1983.One-yea: Chroiiic Oral inhibition. The proposed RMCL of 0.009 absorbed readily and rapidly by all Study in Beagle Dogs wlth Carbofuran. mg/l i8 considered protective of the 70 likely routes of human exposure: oral, Study No. FMC A81-805/Toxigenlcs kg adult for whom there is assumed a 20 dermal and inhalation. Carbofuran's 410715. EPA Accession No. 2507.K~ percent contribution to exposure from oxidative metabolites, 3- 250744). Groups of animals were drinking water. This RMCL is also hydroxycarbofuran and 3- administered daily doses of 0,10,20 or considered to be protective of the 10 kg ketocarbofuran, also presses significant 500 ppm carbofuran in the feed. These child over duratlons of exposure of lees- cholinesterase Inhibitory propertlee. On dletay levels carresponded to than-lifetime and for whom drinking the other hand, the hydrolytic approximate daily doses of 0, 0.25,O.S or water conetitutee a greater contribution metabolites, 3-keto-7-phenol and 7- 12.5 mg/kg bw/day. From the results of to total exposure. hydroxycarbofuran phenol do not. thle study, it was determined that the Queetlons for Comment: Excretlon of carbofuran metabolites Is mlddle dose (0.50 mg/kg/dey) was the

F4701 rev. 0-14-85 Foderal Register I Vol. 50, No. 219 I Wednesday, November 13, 1985 I Proposed Rules 48987 .- . - NOAEL, based upon the absence of a well as possible reproductive and tot^ of five States. One state found that biologlcally slgnificent depression of Immune effects. An RMCL of 0.038 mg/l 42 percent of the systems aii~lyzed(87 cholinesterase activity or reproductive is boned upon the AAUl of 0.18 mg/l and ground systems) were positive. In the effect in the males. Applylng an an assumed drinklng water contribution 1975 Region V Survey. on(! srimple uncertain1 factor of 100 lo the NOAEL of 20 percent. contained gamma-chlordrine ut u level of of 0.50 rngrkglday and assuming 5. Chlordane 0.004 pg/l (detection limit not reported). consumpllon of 2 liters of water pey day, Contamination of public wHter ap. AD1 of 0.005 mg/kg/day and an Chlordane (1,2,4,5,8.7.8,8-octachloro- systems has been reported in several AADl of 0.18 mgil was calculated for 2.3,3a,4.7,7a-hexehydro-4,7methano-l~l- cases which occurred from bock the 70 kg adult. This AADl is supported indene: CAS st 57-74-9) le a broad syphonege from tank filling operations further by evidence from the &year rat spectrum lnsectlcide. Technical during pesticide apdicutiona. chlordane is a mixture of stereo-isomers feeding study (FMC Corporation, Chlordane has been identified tit thi,l:c! Agricultural Chemical Croup. 1980. Two- and other chlorinated analogs, \ncluding hazardous waste sites dosiRniited in year Dietary and Carcinogenicity Study heptachlor. The water solubillty of complaints rind consent dcc:rc!er. under in Rats. Carbofuran Technlcal Report chlordane is 150-220 g/l at 22 'C. the Comprehensive Emergency No. Act. 130.51. EPA Asaession No. Chlordane is relative6 non-volatile with Response Compensation rind Lirilility 244491). In this study, groups of rats a vapor pressure of 1~10-~mm Hg at 25 Act of 1980 (CERCLA) and the Nationti1 'C. were fed 0, 10,20 or 100 mg carbofuranl Contingency Plan (40 CFR Prirt 300). 'I'he kg dlet for 2 years. A NOAEL Of 1 mg/ Chlordane le currently the most concentration of chlordane ranged from kglday (the middle treatment dose) was extensively used Insecticide for unknown amounls migrating in water. subterranean termite control in the identified, to which an uncertainty 782-2300 mg/I in sediments. 11) 101 mg/I factor of 200 was applied to protect Unlled States. Prior to the 1977 cencellatlon of registrations for in noil. aqainst cholinesterase depression and Health Effects. The principul non- systemic effects. Again assuming agricultural and home garden use. chlordane was used for the control of carcinogenic effects of chlordiine from consumption of2 liters of water per day, both acute and chronic exposure include and AADl of mg/l was calculated soil Insects and ants. 0.18 Analytical Methods. Analytical neurotoxicity, induction of hepatic for the 70 kg adult. Both of these studies microsomal enzyme activity rind liver' which were used to determine the methods available for analyzing chlordane in drinking water include the effects. provisional AADls are long-term studies Sufficient dose response data were (1-year and 2-years) with many dose solvent extraction chromatogrsphy and solvent extraction-gas chromatography/ not availob!e to derive 1-day levels. These ntudies are more assessments. However, it should be appropriate for determining a lifetime mass spectrometry techniques. Human Exposure. In the FDA FY 77 noted that the ten-day assessment number then the human data (used to would also be protective for the one-day determine the short-term assessment) compliance program report on pesticides and metals, chlordane was detected in exposure. Ten-day assessments were which consisted of one dose applied in a based upon a study in which rats were single exposure. 2.8 percent of foods sampled. Chlordane occurred in 1.8 percent of raw given by gastric intubation doses of 0. The mutagenic potential of carbofuran agricultural product samples, 9.3 percent 8.25, 12.5. 25.0. 50.0,100.0 or 200 mg/kg has been tested in a number of short- of fish snd marine animal samples. 0.2 chlordane for 15 days (Ambrose. et el. term assays. The majority of the results percent of processed food samples, 1.4 1953. Toxicological and Pharmacological presented no evidence of mutagenicity. percent of processed animal feed Studies on Chlordane. Arch. Ind. t-lyg. Two studies yielded equivocal results. samples, and 2.5 percent of egg and egg Occup. Med. 7:197). The minimal The carcinogenic potential of carbofuran product samples. In the FDA FY 79 total histopathological changes such as was evaluated in lifetime dietary studies dietary study for adults, no chlordane presence of abnormal intrtlc;.topiasmic In the rat and the mouse (FMC was detected in any of the samples. bodies of various diameters were Corporation, Agricultural Chemical The USDA reported chlordane evident at a dose level of R.25 mg/kg. Group. 1980. Two-year Dietary Toxicity residues in violation of maximurn Using 8.25 mg/kg as the LOAEL, an and Carcinogenicity Study in Rats. allowable levels (300 ug/kg on raw uncertainty factor of 100 based upon an Carbofuran Technical RepIrt No. ACT agricultural commodities) in 0.1 percent animal study and consumption of 1 liter 130.51. EPA Accession No. 244491: Ibid. of fat samples of various animal species (child) or 2 liters of water (adult) per 1980. Two-year Dietary Toxicity and Intended for humaq consumption during day, 10-day assessments of 0.083 mg/l Cercinogenlcity Study In Mice. the ears 1982-1983. for a 10 kg child and 0.22 mg/l for a 70 Carbofuran Technical Report No. ACT Cglordane has been detected in kg adult were calculated. 150.52. EPA Accession No. 244489). In ambient air at levels as high as 204 ng/ An AADl for chlordane was derived neither study were there statistically m? In the Surburban Air Sampling based upon a two-year feeding study in increased lumor incidences attributable Program in 1975,15 samples were dogs where 0.075 mg/kg/day (3 mg/kg in to exposure to the compound. collected at three suburban locations. diet) was identified as the NOAEL Carbofuran has been classified In EPA's Nine samples were positive for (Veltorazzi, 1975. Toxicological Croup E, according to EPAs Proposed chlordane with a maximum value of 59 Decisions and Recommendations Guidelines for Risk Assessment, based ng/m? Resulting from the Safety Assessment of upon the negative results in studies in Chlordane has occasionally been Pesticide Residues in Food. Crt. Rev. rats and mice. reported in wells near areas treated for Toxicol. 4:125). Using 0.075 mg/kg/day EPA is proposing to regulate termlte control. In addition, chlordane as the NOAEL, an uncertainty factor of carbofuran because of Its potential was detected at low levels in the New 100 based upon an animal study and adverse effects on health and potential Orleans Water Supply Study conducted consumption of 2 liters of water per day, for occurrence in drinking water. by EPA. Five wells in New jersey an AADI of 0.03 mg/l was calculated. Exposure to carbofuran at sufficient contained chlordane above 0.01 &I Chlordane was shown to be levels results in a rapidly-reversible (range 0.01-0.02 pg/l). Chlordane has mutegenic in studies with transformed inhibltion of cholinesterase acllvlty, as been detected In drinklng water in a human cells in culture. A National

S-074999 0087(OSX12-NOV-8S-I S:2S:24) .- .- F4701 rev. 8-14-85 46988 Federal Register / Vol. M), No. 218 / Wednesday, November 13, 1885 / Propoeed Rules I Cancer Institute study (NCI. 1977a. Analytical Methods. Analytlcal Antifertility effects In men have been Blonnaay of Chlordane for Possibla methods avallable for analyzlnll DBCP associated with exposure to DBCP. CarclnoRenlcity. NCI Carcinogenesis. in drinking water include the purge and One-day assessments were calculated Tech. Rep. Ser. No. 9) examined the Irap-gas chromatography and the purge based on a study in rates (Kluwe, W.M. cnrcinogcnlc effects of chlordane. Male and trap-chromatography/mass 1985. Initial and Residual Toxicity and female mice were fed diets spectrometry techniques. following Acute Expoeure of Developing contalning analytlcal-grade chlordane Human Exposure. DBCP residues Male Rata lo DlbromochlorobroDane. for 80 weeks, with the results showlng a have been detected In U.S foods. In Toxicoi. Appl. Paramocol. 7e':54&l highly signincant dose-dependent 1978, the FDA detected reeldues In where single day, subcutaneous doses of incidence of hepatocellular cacinoma in carrots grown in soil fumigated wlth DBCP induced renal lesions in &day-old both male and female mice. Hepatic DBCP. Levels ranged from 20-1,500 pg/ rats. Using a 20 mg/kg/day LOAEL, an nodules and liver hyperplasia were also kg. Residues were detected in broccoli, uncertainty factor of 1o00, and produced In rats. A study examinlng the cabbage, cauliflower and cucumbers in consumption of 1 llter (child) or 2 llters reproductive effects of chlordane the range of 10-1,120 !cg/kg. (adult) of water per da ,l-day concluded that chlordane in the diet (16 Additionally, reeldues were detected in assessments of 0.2 mg) for a 10 kg child mg/kg) of male and female rats from eanut kernels in the range of 10-40 pg/ and 0.7 mg/l for a 70 kg adult were weanlng appears lo interfere with Lo calculated. fertility and survlval of the lltters The FDA compliance program report Ten-day assessments were calculated (Ambrose, et al. 1953a. Toxicological for FY 78 reported realdues of DBCP in based on a NOAEL of 0.5 mg/kg/day for ond Phermacologlcal Studiea on samples of domestic and Imported fish. increased kidney welghls in a W-dey Chlordane. Arch. Ind. Hyg. Occup. Med, Seven (0.6%) out of 1,516 fish samples feeding study wlth DBCP In rats 7:197). Tho IARC classified chlordane in contained DBCP in excess of the (Torkelson, T.R. et el. 1961. Toxicologic Croup 3: Inadequate evidence for detection limit. Iwestigations of 1,2-dibromo-3- carcinogenicity In humans, limited DBCP has been detected In ambient chloropropane. Toxlcol. Appl. evidcnce for carcinogenirity in animals air. One composite study of volatile Phermacol. 3:545). Using an uncertainty organic chemicals in the atmosphere and inadequate evidence for activity in factor of 100 and consumption of 1 liter short-term tests. Chlordane has been from locations nationwide showed the (child) or 2 litera (adult) of water per classified In EPA's Group 82, accordlng pressure of DBCP in ambient alr day. 10-day armessments of 0.05 mg/l for to EPAs Proposed Guidelines for eamples In one location. A mean a 10 kg child and 0.175 mg/l for a 70 kg Carcinogen Risk Assessment, based concentration of 6.4 ng/mJ in seven air samples was calculated for DBCP adult were calculated. upon studies showing positive results in A provisional AADl was not mice and female rats. (median, 1.8 ng/ms). determined for DBCP due to insufficient EPA's CAG and the NAS have Several regional studies have data. The taste and odor threshold for calculated risk estimates (see Table 13) documented the presence of DBCP in based upon the NCI study. ground water. Positive samples have DBCP in water has been reported to be The WHO recommended guideline been detected in Hawaii, California, 0.01 mg/l in the Iiterahne. value (1984) is 3 pg/l for chlordane. This Arizona. South Carolina and Maryland, The NAS (Drinking Water and was based upon an acceptable daily with concentrations typically ranging Health, 1977 and 1981. Vole. I and IV) intake of 0.001 mglkglday, with the from 0.02-20 pgll. One of these States did not calculate a Suggested-No- assumption that not more than one found 62 out of 82 samples to be Adverse-Response-Level (SNARL) for percent of the AD1 would be derived positive, in ground water. DBCP is DBCP. They felt that it would be from drinking water. reported to be mobile in runoff and premature to calculate a SNARL for A detection and odor threshold value through soils. pure DBCP since the contaminants in of 0.005 mg/l has been reported In the DBCP has been identified at one technical DBCP could be responsible for literature for chlordane. hazardous waste site designated in toxicological effects in animals and The available data indicate that complaints and consent decrees under humans. chlordane has carinogenic effects in the Comprehensive Emergency DBCP has been shown to result in animals. For thls reason and because of Response Compensation and Liability reverse mutations in Salmonella the occurrence of this contaminant In a Act of 1980 (CERCLA) and the Natlonal typhimuriurn, recesslve lethal mutatione number of drinking water supplies, EPA Contingency Plen (40 CFR Part 300). The in D~vsophilamelanogaster, dominant is proposing a primary regulation for concentration of DBCP ranged from 0.08 lethal mutations in rats and chlordane. The RMCL will be based mg/l in drinking water, 95 mg/l in chromosomal damage in rats and upon carcinogenic effects and an RMCL ground water, to 2800 mg/l In soil. DBCP cultured Chinese hamster cells. of zero is proposed. was also detected in ground water at a DBCP has been studied for hazardous waste site in Colorado and a carcinogenicity in mice and rats by oral 6. Dibromochloropropane slte In Callfornia. and inhalation exposure and in mice by Dibromochloropropane (1.2-dibromo- Health Effects.DBCP is absorbed by dermal application. A National Cancer 3-chloropropane (DBCP): CAS #Wb-lz-S) the gastrointestinal tract, the lunge and Institute bioassay (NCI, 1977. Biosssay is a soil fumigant used for nematode the skin and is widely distributed of Dibromochloropropane for Possible control on cropn. DBCP is moderatel throughout the body. Effects of acute, carcinogenicity. NTlS PB279472) soluble in water (approximately 1 gr I). oral exposure to DBCP in rats include reported highly significant dose-related Recent information suggests that DBCP impaired renal function, hepatocelluar incidences in rats of equamous-cell

may readily leach Into aquifers used for necrosis, loss of spermatogenic elements carcimoma of the forestomach of males , drinking water. in the testes and testicular and and females end mammary Uti1 1977, DBCP waB used In epidldymal atrophy. Simllar effects have adenocarcinoma in females receivln commercial agricultural applications. It been observed for subchronic oral gavage doses of 10.7 and 20.7 mg/kg$ was also used for non-crop appllcatlons, exposure, whih chronlc exposure In day. Significantly increased Incidences including commercial turf. Presently all anlmals has resulted in high Incidences ,f squarnous-cell carcinoma of the uses have been cancelled. of toxlc tubular nephropathy. forestomach of male and female mice

S-074999 ~88(05XI2-NOV-8~-lS:25:26) r4701 rev. 8-14-85 Federal Register / Vol. 50, No. 218 / Wednesduy, November 13, 1985 / Proposed Rulee 46989 t were found at doses of 78.8 to 158.4 rngl water, EPA Is proposing to regulete approxlmate 0.0.0.030,0.56 end le pg/ kdday. DBCP. The RMCL will be bused upon ma, respectively. The estimrited A chronlc dletary carclnogenlclty carcinogenic effects end an RMCL of reeplratory intakes for the edult mule study [tlazelton Laboratories America, zero le proposed. and formule-fed infant can vHry Inc. 1977. One Hundred Four-Week Question for Comment: between 0-5.3 and 0-3.7 pglkuldiiy, Dietary Study In Rate; 1.2-dibromo-3- 1. la there adequate evldence reepectivel y. chloropropane (DBCP). Final report. lndlcoting that the contaminants in Using data for eurfricc wiitiv rind Unpublished report submitted to Dow DBCP account for the toxiclty of the ground water suppllcs. it is c:stimuted Chemical Co., Midland, MI. Oct. 29, compound? that 99.3 percent of the populiition 1977) reported that male and female 7.0-, m.Dlchlorobenzene served by public drinking witlcr nyntims rate, at a dose of 2.0 mg/kg/day, as are receiving wiitdr with no o- estimated in U.S. EPA. 1979,44 FR 85136, 0- and m-Dlchlorobcnzene [CAS fn dichlorobenzene or levda lcnn thHn 0.5 exhlblted elgnificantiy increased 95-50-1,541-73-1) are solvents with IOW pg/l and that 0.7 percent may i)e lncldencee of carcinoma of the renal vapor pressures. o-Dichlorobenzene le exposed to lcvels of o-dichiorobenzenr! tubules. hepatocellular carclnomae and used primerlly in the production of in drinking water at or UIJOW 0.5 pg/I. organic chemicals, including pesticldes equomoue-cell carclnoma of the The vast mejorlty of CUBBB of drinking stomach. DBCP has been shown to and dyes. It also has dlrect solvent and woter contemlnation in in nurfHce wiiti:r result in increased Incidences of nasal peetlcidal uses. supplies. rn-Dichlorot)cnmnc wits not cavlty tumors in mice through inhalatlon Releases of o-dichlorobenzene to air detected in the Ground Wuler Supply were estimated to be between 118 and exposure, Survey. o-Dichlorolicnzcne hus been The IARC have classified DBCP In 208 kkg in 1983. Industrial losses of m- detected in westcwatere rind hnziirdoua dlchlorobenzene were reported to be Group 28; inadequate evldence for wastes, le mobile In runofl rind eoiln rind carcinogenlcity in humane and eufficlent 0.1856.808 kkglyear In 1983. Isomers of large amounts are produced Hnd used evidence for carcinogenicity In animals. dichlorobenzene appeor to vaporize DBCP has been claaslfied In EPA'n ropldly from surface waters. despite across the country. EfJecta. The principul loxic Group 82, accordlng to EPA'a Proposed their low vapor pressures, and are Itcolrh Cuidellnes for Carclnogenlc Risk expected to degrade slowly In the effectn of o-dichlorobenzene in hunirina Assessment, because there are results in envlronment. and other animals from acute end studies In anlmals (rats and mice). Analytical Methods. Analytical longer-term exposures include central Based upon the tumor incidence for methods ava!lable for analyzing o- and nervous system depression. blood liver. kidney and stomach in rata from m-dichlorobenzene In drinking water dyscraeias, lung, kidney wid liver the chronlc dietary carcinogenicity include the purge and trap-gas damage. Similar data are not available study discussed above, CAC has chromatography and the purge end trup- for m-dichlorobenzene. However. based estimated the possible carcinogenic risk gas chromatography/rnase spectrometry upon the results of a few studies in of lifetime exposure to DBCP for a techniques. short-term assay systems. the meta- person consuming 2 liters of water per Human Exposure. Data on isomer appeers to be similar in toxicity doy. This risk estimate is shown in dichlorobenzene in the US. food supply to the ortho-isomer (apparently. not Table 13. are limited. Ortho- and m- showing greater toxicity). Therefore. the The Shell Oil Company (Health dichlorobenzene have been reported in short-term assessments developed for o- Effects Evaluation and Risk Assessment fish from the Great Lakes (0.3-3.0 pg/ dichlorobenzene also will bc used for m- of DBCP submitted to Criteria and kg). In one study reported in 19Bo,42 dichlorobenzene. Standards Division, Office of Drinking namples of milk from nursing mothers in No aatisfectory does-response data Water. EPA, Dec. 1983) has derived risk New jermy, Pennsylvania, Louisiana exist from which to derive e 1-day estimates based on the tumor incidence and West Virginia were found to assessments for either o- nr m- for liver, kidney and stomach in rate contain a mean level of 9 pg/ml of dlchiorobenzene. It is recommended from the same study. Using the dichlorobenzene Isomers. All samples that, for this duration of exposure. the geometric mean of five models (problt, were positive for dichlorobenzene with 10-day level be applied. logit, Weibull. gamma multi-hit and a maximum level of 88 pg/ml. The The 10-day assessments were derived multi-stage) and three dose scaling highest levels reported in the study were from results of mouse and rrit factors (mg/kg, ppm, and mg/m"j for found In samples from New Jersey and subchronic gavage studies (Dettelle- each data set. the Shell Oil Company Louisiana. Columbus. 1978~.Subchronic Toxicity: calculated rleke from lifetime exposure Data indicetin8 the level of o- and m- Ortho-dichlorobenzene. &GFl mice. to DBCP in drtnking water. These risk dichlorobenzene in ambient air are Unpublished report: Battelle-Columbus, eetlmatee are as follows: available from studies conducted in 1978i. Subchronic toxicity: Ortho- 4.8 x IO-#from lifetime exposure to many States. From the medlan values of dichlorobenzene. Fischer 344 rets. DBCP based on male rat data. these data, it is esiimated that rural/ Unpublished report). Treated mice and 2.2 x 10-"from lifetime exposure remote, urban/suburban and source rate received single doses of 0. 30.80. to DCBP based on female rat data. dominated dichlorobenzene in ambient 125.250 or 500 mg/kg/day in oil. five 3.7 x lo-' from one-seventh lifetime air approximate 0.0, 8.e and 350 ng/m? days/week, for 90 days. A NOAEL of exposure to 100 ppb DBCP based on respectively. The estimated respiratory 125 mg/kg/day was Identified for the male rat data, intake for the adult male is ex ected to mouse as well as the rat. Using this 1.5 x IO-' from two-seventh vary between zero and 8.2 pgfkglday. NOAEL applying an uncertainty rector lifetime exposure to 100 ppb DBCP Respiratory intake for formula-fed of 100 baoed upon an animal study in based on male rat data. infante could vary between 0 and 4.3 whlch a no-effect level was Identified. e The availabre data indicate that DBCP PB/kg/daY* factor of H to account for conversion has non-carcinogenic and carcinogenic Median values of data also indlcatre from a 5 day/week dosing regimen to a 7 effects in animals. Based on potential that rural/remote, urbanleuburban, day/week and assuming consumption of adverse health effects and occurrence source dominated and maximum levels 1 Iller of water per day, a 10-dey and potenlial occurrence In drlnklng of rn-dichlorobenzene ic smblent air assessment for the 10 kg child of 8.9 mg/

Sa14999 0089(05KIZ-NOV-85-IS:25:28) 48990 Federal Register / Vol, 60, No. 218 / Wedneeday, November 13, 1985 / Propoeed Rulee

I was dorlved. A 10-day aasessmenl of and lndustrlal Experlence. AMA Arch. chlorlde, Is a solvent consisting of a 31.2 mg/l for the 70 kg adult, who Is Ind. tilth. 17(1):180-187). The WHO mixture of cls- and trans-isomers. Their annumed to drlnk 2 liters of water per proposed drinklng water guideline for proportion varies depending on day, rilso was derived. the ortho- Isomer is 0.3 pg/L based upon production conditions. The cis- and The data base selected for derivation organoleptic consideratlone. The NAS trans-Isomers have vapor pressures of of the provisional AADl for 0- Safe Drinking Water Committee 180 and 285 mm Hg at 20'C respectively, dichlorobenzene was the subchronic recommended a tentative chronic and water. nolubilitlea of 3.5 and 6.3 g/l, giivnge studies in rats ond mice SNARL of 0.3 mg/l for the orthoisomer, respectively. 12-Dlchloroethylene is described tlbovc for the deriviation of iislng the lowest dose (e0mg/kg) In the used as a low-temperature extraction the Io-day assessments. Using the carclnogenicily bloaesay (NTP, 1982. See solvent for organic materlale, and as a NOAEL of 125 mg/kg/day, an above) and asaumlng that a 70 kg adult chemical intermedlate in the syntheele uncertainly factor of 1000 based upon an consumes 2 llters of water per day, an of other compounds. The principal animal study of less lhirn llfetime uncertalnty factor of IO00 and a factor of source of these dlchloroethylenes in exposure, a factor of H to account for 5/7, with 20 percent contribution of drinking water appears to be from In conversion from a5duylweek dosing exposure from water (Drinking Water situ transformations from other regimen to 7 dny/weck and consumption and Health, 1983. Vol. 111). chlorinated hydrocarbons. of2 litera of water per day, a provisional The ambient water quality criterla for Analytical Methods. Analytlcal AADl of 3.12 mg/l was determined. o-dlchlorobenzene was based upon an methods avallable for analyzing cie- and The dichlorobenzenas poasese older study with a lower NOAEL the! trans-l,2-dlchlorocthylenein drlnklng mutagenic activlly in certain lest was used to develop the provislona' water Include the purge and trap-gas systems. Neither were posltive in the AADI, whlle the WHO guideline +:d not chromatography and the purge and trap- Amce/Salmonella or E. coli WP2 conslder health effects In the de!~vatlon gas chromatography/mase spectrometry mulogenlclty assay systems. However, of the number. The NAS SNAdL was techniques. m-dichlorobenzene, both with and based upon a chronic study whlch only without metnbolic actlvatlon, Increased Human Exposure. No data are examined one purameter, whlle the avallable on levels of 1,~- mltotic recomblnatlon in S. cerovisiae. subchronic study upon which the The orthoisomer was shown to produce dichloroethylene in Ihe U.S. food supply. provisional AADl was based examined Llttle data are available on the level abnormtll mitotic dlvision In the unlon, many parameters. Allium cepo. Both o- and m- of trans-1.2-dichloroethyleneIn air. The odor thresholds for the Limited sampling at one site resulted in dichlorobenzene were shown to interact dichlorobenzenes In water range from with and damage bacterial DNA in the the detection of levels around 4 pg/m'. 0.01 to 0.03 mg/l. Amblenl alr monitoring for the cis- E. coli W3110 polA'/p3478 pol A- Exposure to ortho-dichlorobenzene at isomer is available from 10 States. differential toxicity assay system. high dose levels results In a variety of o-Dichlorohenzene has been tested by toxic effects, Including central nervous domlnated, and maxlmum levels of cle- govnge for carcinogenic potential In rats system depression. kldney and liver 1,2-dlchloroethylene In ambient air and mlce in the NTP Bioasaay program damage. Becaune there le also sufficient approximale 0.0, 0.27,l.Z and 27 pg/m? (NTP, 1982. Draft Technical Report nn occurrence potentiel In drlnklng water, a reepectlvely. Using these data, the Carcinogenesis Bioassay of 1,2- Revised Regulation will be proposed estimated respiratory intake for the dichlorobenzene (CAS # g!i-!i0-1) In and the RMCL wlll be besed upon non- adult male wlll vary between zero In F3441N rats and B,CsFI Mice (Gavage carclnogenlc effects. An RMCL of 0.62 rural areas to 8.9 pg/kg/day following Study). Draft report). A draft report of mg/l is proposed for ortho- exposure at maxlmum levels. the results suggests that o- dichlorobenzene based upon a Resplratory intake for formula-fed dichlorobenzene was not carclnogenlc provisional AADl of 3.12 mg/l and Infante would vary between zero and 8.2 under the test conditions. Thle le a aseumlng 20 percent contribution to total pglkglday. preliminary assessment and no final exposure vla drlnking water. An RMCL Using comblned data for surface determination has been made on the is not being proposed for meta- water and ground water supplies, up to carcinogenlclty of o-dichlorobenzene. o- dichlorobenzene due to the lack of long- 2.2 percent of the U.S. populatlon le Dichlorobenzene has been classified In term compound-epeclfic toxlclty data. estlmated to be recelving water EPA'e Croup D, according to EPA's The only data available on the simllarlty contalnlng ~0.5pg/l of 12- Proposed Guidelines for Carcinogen of toxiclty between ortho- and meta- dlchloroethylene, and 0.2 percent of the Risk Assessment, baaed upon the dichlorobenzene conslsts of data from populatlon could be receiving drlnklng preliminary results of NTP bioassay. short-term systems. Thle data was not water with 1,2-dlchlorethylene levels The IARC classified o-dichlorobenzene consldered to be sufficient to propose an greater than 20 pg/L In Group 3: Inadequate evldence of RMCL for the meta- Isomer based upon Health Effects.The principal toxlc carcinogenicity In humane, inadequate the toxicity of orthodichlorobenzene. In effects of cls- and !rsns-l,Z- evidence for carcinogenicity in animals addltlon, the potential for contamination dlchloroethylene following acute and inadequate evidcnce of activity In of drinking water supplies by meta- exposure are upon the liver and kldney. short-term tests. m-Dichlorobenzene has dichlorobenzene appears to be remote In addition, these compounds possese n:~tbeen tested for carcinogenicity and and lower than the potenllal for eithel general anesthetic and narcotic thus hqs also been clasnified In EPAa the ortho- or the para-Isomer. properties at exposure levels above Croup D. Queetlon for Comment: those at which her and kldney effects EPA'e ambient water quality criterion 1. Would an approDrlate approach be are seen. No data are available (US. E?A. 1980. Ambient Water Quallty to develop an RMCL for m- following longer-term exposures. Criteria for Dichlorobenzene. 440/5-8- dichlorobenzene based upon the toxicity One-day asseeements for cie-1.2- 039) for o-dichlorobenzene le 2.8 m /I, data on o-dlchlorobenzenet dlchloroethylene were derived from an based uporr the NOAEL of 18.8 mgfkg animal study (Jenkins,L.J., Jr., M.J. Identified In the 1958 Hollingeworth, et 8. cis- and trans-1,2-Dlchloroethylenee Trabelus and S.D. Murphy, 1972. al., study (Toxlcity of o- 1,P-Dlzhloroethylene (CAS #e 168-68- Biochemlcel Effects of 1.1. dichlorobenzene: Studlee on Anlmals 2, wCr5O-u: also known as acetylene Dlchloroe thylene. Toxicol. Appl.

S-074999 0090(05)(12-NOV-85-15:25:30) F4701 rev. 6-14-85 - Federal Regleter I Vol. 50, No. 210 I Wednesday, November 13, 1985 I Propoeed Rules 48891 -- Pharmacal. 23:501-510]. In this study, the No setisfactory dose-response date be mutugenic in the hoet-mediated taesiiy authors identified what is interpreted to are available from which to derive IO- using Solmonello tenter atrriinn in mice bo a LOAEL. In measuring lovels of day assessments for trans-l,t- (Cerna. M.and tl. Kyanovti. 11)77. three liver enzymes and two plasma dichloroethylene. Thus, it has been Mutagenic Activity of Chlorocthylnnc8 enzymes, all indicatore of liver function, determined that, in the absence of Analyzed by Screening Syntcm I'cels. the investigators showed that a eingle compound-specific data, the data for 1,1- Mut. hes. 48214 Abet.). Thf! nlime 400 mg/kg oral dose to the rat produced dichloroothylene used above for the authors observed that the ciw isomer a significant change only in liver calculation of the 10-dny nesessments ale0 produced chromosomal ali(!rrirtioiiR elkaline phosphatase, while the levels of for the cis-isomer ore uppropriate for the in mouse bone mtirrow ct!lis follriwing the other four enzyme8 were not trans-Isomer, as well. Therafore, tho 10- intrnperitoncel injections. Affected significantly. The 1-day day aaeessment for the 10 kg child No long-term stu lies htive lwcn assessment for thP 10 kg child Of 4.0 m / would be 1 mg/l, and, for the 70 kg carried out on the ctircinollcnic potcntiitl I is derived from the LOAEL of 400 mg$ adult, 3.5 mg/l. of cis- and trnns-1.2-dichioroc~thylenc kg, using an uncertainty factor of 1000 An AADI for the 1,Z-isomers of and thus both isomere hHvi! been since a NOAEL wee not determined and dichloroethylene could not be developed claaaified in Ei'A's Croup U. iiccortling an asaumed consumption of one liter of from compound-specific data slnce these to EPA's Proponed Cuidclincn for water per day. A compereble I-dey levo1 data do not exist ut this time. Two CarcinGgenic Risk ARet!ntImc!nt. for the 70 kg adult would bo 14 mg/l, options aro evailoble. The first is lo Exposure to CIS- and trtinn.l.2- assuming the ingestion of 2 liters of propose no AADI at all. The second it^ to dichloroethylenc el hlgh doat! Icvcln wnter per dny. apply an AADl developed from data on results in liver and kidney offcctn. Sinw No satisfactory dose-response data 1,l-dichloroethylene.The aveiltible there is widcnprend occurri!ni;c of Ihi!n(! ere available from which to derive 10- Information from shorter term cxponures conlaminante, EPA proposes lo ri!Muliitt! day assessments for cis-1,Z- lo all three of theso compounds suggests thcm. The proposed RMCI, (if 0.07 mR/I dichloroethylene. Evaluelion of the that the non-cercinogenlc toxicity is bawd upon an AADl of 0.:15mR/I for available toxicological data on cis-1,2- induced by the 1.2-isomers is llkely to be both cie- end truns-1.2-dichloroeth~lcni~ of 1,1- dirtti 1.2- dichloroethylcne and 1,l- no more severe thon thd effects dcrived from on dichloroethylene. Since the endpoints of dichloroelhylene assuming 20 percent of dichloroethylene euggesls that a ten-day non-carcinogenic toxicity to all three the exposure is via drinking water. assessment can be derived from data in dichloroelhylenee are essentially Question for Comment: the @day drinking water study in rats identlcal, applyiiig the AADl developL with 1,l-dichloroethylene (Rampy, et el., 4 1. In the ebsence of cornpound- for 1,l-dichlorocthplcne to the 1,2- specific data. is it reesonelilr! to develop 1977). A NOAEL of 1.70 ppm (10 mg/kg/ ieomers may even result in en added an AAUl for cia- and trans-1.2- bw) wes identifieu in 'his study. margin of safely. Applylng an uncertal.ity factor of 100 dichloroethylene from toxicity data on The study selected for the derivetion l,l-dichloroethylenc? and assuming consumplion of 1 liter of of the AADl was a two-year chronic water per day, the ten-day aanessment loxicily/oncogenicily study in which 9.1.2-Dichloropropane for the 10 kg child would be 1 mg/l. A male and female rats were given 12-Dichloroyropune (propylene comparable ten-day level for the 70 kg concentrations of 0,50,100 or mg/l 1. dichloride; CAS 078-87-5) is a solvent 3.5 mg/l, 200 adult would be assuming the I-dichloroethylene in their drinking and a pesticide. United States ingestion of 2 litere of water per day. water (Quest, et el., 1883. A Chronic production of 12-dichloropropane was One-day assessments for trans-l,2- Toxicity and Oncogenicity Study in Rata approximetely 77 millior, pounds in 1980. dichloroethylene were derived from an and Subchronic Toxlcity Study in Dogs Primtlry uses of 1,2-dichloropropane animal study (Freundl, K.J., G.B.Liebalt on Ingeeleu Vinylidene Chloride. Fund include: eoil fumigation for nematodes end R. Liberwirth. 1977. Toxicology Appl. Toxicol. 3:55-82). In the highest and other insects; sclvent for metal Studies 011 trans-1.2-Dichloroethylene. dose group. significant microscopic degreasing. fats. oile. waxes. gums, and TOXICOI.10131-138). This etudy changes were noted in the livers of resins; intermediate for identified a NOAEL of 200 ppm lnhalud anlmals of both sexes. Minimel perchloroethylene and cerbon by mature female rats over a single 8- hepatocellular swelling and fatty tetrachloride; lead scavenger for anti- hour exposure period. This exposure changes ware detected in female rats at knock fluids; and in dry clctaning fluids. resulted in slight liver effects in one of all doee levels. An AADl of 0.35 mg/l Analytical Methods. Analyticel eix animals, as observed histologically. was determined using a LO.IEL of 100 methods available for analyzing 12- No changes were observed in eeveral mg/I (or 10 mglkg), and uncerteinty Dichloropropane in drinking water serum biochemical parameters. A total fector of lo00 based upon an animal include the purge and trap-Rue absorbed dose of 27.2 mg/kg was study with the NOAEL not identified. chromatography and the purge and trtip- estimated by converting ppm into mg/rna and consumption of 2 litem of water per gas chromatography/mass spectromet;y [200x3.87) and muitiplying by 8 hours' day. techniques. exposure. assuming that 30 percent of Both cia- and trane-I, 2- Human Exposure. No dfltii were the exposure dose was absorbed, then dichloroethylene were non-mutagenic available on the levels of 12- dividing by 70 kg. The 1-day aesessment when assayed with E. coli Kl2 at eimilar dichloropropane in ambient Air or in 'for the 10 kg child of 2,7 mg/l wae concentretlone uee for 1.1- food. derived by applying an uncertainty dichloroethylene at which the latter wtrs 1.2-Dichloropropene was found in o of factor of 100 to the total absorbed doee found to be mutegenic (Griem, et al. 488 randomly sampled drinkink watrr [in mg/kg) and assuming consumption of 1975. Mutagenicity In Vitro and systeme in the GWSS. The menn level 1 liter of water per day. A I-day Potential Carcinogenicity of Chlorinated found was 3.7 ug/l. In non-rendomly assessment of 9.45 mg/l for the 70 kg Ethylerred as a Function of Metabolic selected samples, 1,2-dichloropropanc adult would be dedved in the same Oxirane Formation, Biochem. was observed in 7 out of 479 syetems manner, but, assuming a consumplion of Pharmacol. 24:2013-2017). Cis-,but not with a mean concentration of ~ug/l. 2 liters of water per day, Irane-i,2-dlchloroethylenewee found to High concentrations have been reported

F4701 rev. 8-14-85 46882 Federal Register 1 Vol. 60, No. 210 / Wednesday, November 13, 168S / Proposed Rules in cnnes of contaminated round water. metabolic activation. In a cancer risk level as calculated by EPAe 1,2-Dichloropropanewas f ound in 60 out carcinogenesis bioassay of 1,2- CAG. of 410 drinking water wells in several dichloro ropane conducted by the Questions for Comment: counties throughout Califomla between Nationa PToxicology Program (NTP 1. Are there data available on the 1979 and 1983.1,2-Dlchloropropanehas Draft Report, 1982), rats were toxicology of 12-dichloropropane which also been detected in wells in New administered 1,2-dichloropropaneIn may be used for the derivatloil of a York. corn oil by gavage. In their draft report. provisional AADl? 1-2-Dichloropropanehas been the NTP reported significant increases In 2. Should 12-dichloropropane be identined at one haznrdous waste site in non-neoplastic liver lesions (foci of clear classified in EPA's Croup C? What complaints Hnd conacnt decrees under cell change, centrilobular necrosis) and should be the basis for the RMCL for the Comprehcnslve Emergency mammary gland adenocarcinomas in this compound? Reeponse Compensation nnd Liability female rats, but treatment related non- Act of 1R80 (CERCLA) and the National neoplastic or neoplastic effects were not 10.2,4-D Contingency Plun (40 CFR Part 300). The observed in male rats. 2,4-D (2,4-Dichlorophenoxyaceticacid; concentrnlion of 1,2-dichloropropane In a NTP mice study (NTP Draft CAS #94-75-7; current MCL is 0.1 mg/l) rengcd from 74 ug/l in soil lo 1800 ug/l Report, 1082), non-neoplastic liver is a systemic herbicide used to control in runoff. lesions were observed in male mice broadleaf weeds. 2,4-D is sold as a ileolfhEffcct8. The principal target only, but hepatocellular adenomas were variety of salts, esters and other orxan for 1,2-dichloropropane toxicity increased In both male and female mice. derivatives which are very soluble in Hppenrn to bc the liver. Centrilobular Under the conditions of these studies, water. 2,4-D and its derivetives undergo nccrosia, liver congestion and he atlc 1,2-dichloropropane was considered to both chemical and biological fntty chrlnges huve been reporte B in be carcinogenic for male and female degradation when released to the animuls. Effects on the kidneys and mice and the effects of 1.2- environment. Soil residues break down lungs have nlso been reported in animal dichloropropane in rats were considered in approximately six weeks and studiee. There are insufficient equivocal. It should be noted that these repeated application usually does not toxicologlcel data available in the reeulls are reported in the draft NTP lead to accumulation. Phenoxy scientific literature to calculnte a 1-day report and the study is currently being herbicides undergo photolysis and assessment for 1,2-dlchloropropane.The audited. The final results may change 10-day aesessment la recommended to bacterial degradation. when the audit is completed and 80 of be applied to a 1-day exposure. Nearly percent the domestically reported by the NTP. available 2,443 is used on agricultural Ekshtat, et el. (1975. Study of the EPA's CAG have derived eslimalea of Cumuletive Properties of Substances at crop sites. The remainder ir used on risk of daily exposure to 1,2- range and pasture land, industrial and Different Levels of Acllvlty. Uch.Zap,- dichloropropane bmed upon the NTP Monk. Nauchno-Issled. Inst. Gig. 22:46- mice study. As previously noted, these commercial sites, lawns and turf, forests 48.) reported the results of orally results are reported in the draft NTP and in water. 2,4-D is currently administered 1.2-dichloropropane at report and the final results may change. registered for aquatic weed control in dose levels of 8.8,44 or 220 mg/kg for 20 ponds, lakes, reservoirs. marshes, The CAG riak estimates are summarized bayous, dralnage ditches, canals, rivers days. The investigators observed In Table 13. disturbances in the animals' protein The EPA (1880) concluded that data and streams. formation, hepatic enzyme levels and regarding the toxicity of 1,~- Analytical Methods. Analytical lipid metabolism. The NAS (1979) in a dichloropropane were insufficient for methods available for analyzing 2,4-D in request from the Office of Drinking the derivation of an ambient water drinking water include the Water provided a 7-day Suggested-No- quality criterion for the protection of derivetization gas chromatography Adverse-Response-Level (SNARL) for human health. technique. 1.2-dichloropropane based on the 1,t-Dichloropropane has been Human Exposure. In the 1970-73 FDA Ekshlat, et al. (1975) study in rats, A classified in EPA's Croup C, according total dietary studies for adults, four LOAEL of 8.8 mg/kg/day was used to to EPA's Proposed Guidelines for samples of leafy vegetables contained derive a 7-day level for a 70 kg adult Carcinogen Risk Assessment, based residues of 2,4-D in the range of 10-130 consuming 2 liters water/day. The NAS upon one positive study (NTP Draft ug/kg, and one potato compoffite sample SNARL can be used as an inlertm ten- Report, 1982) in mlce. Thus, 1,2- was found lo contain 14 ug/kg. In the day assessment as well. The 10-day dichloropropane has been placed in 1975-78 total dietury studies for infants level is derived using 8.8 mg/kg/day as Regulatory Category I1 and the RMCL and toddlers, one poaltive sugar and the LOAEL divided by an uncertainty will be set at a non-zero level based adjunct sample (25 ug/kg) was identified factor of IO00 (because data are limited upon the risk level. The reason for in the toddler food analysis. No residues and Incomplete). For a 70 kg adult using a riak level la because the chronic were found in the infant food analyeis. consuming 2 liters of water per day. the toxicity data are extremely limited and FDA's compliance reporte showed that 9 10-day number is 0.3 mg/l. For a 10 kg an AADl has not been established for out of 11 food samples were positive for child consuming 1 liter of water per day, 1,Z-dichloropropane. The lo-*!eve1 was 2.4-D in FY 78,s out of 39 saniples were the 10-day number is 0.08 mg/l. used because of the quality of the positive in FY 80. and 1 out of IO There are Insufficient data available bioassay data which have not been samples was positive in FY 82. to calculate a provisional AADl for 12- validated. 2.4-D has been reported in ambient air dichloropropane. Exposure to 1.2-dlchloropropane has samples from cities in New York and Mutagenicity studies have shown that been shown to result in adverse health Utah at levels as high as 4 ug/ma. Thirty at high concentrations 1,2- effects. For this reason and because percent of the ambient ash air samples dichloropropane induces base-pair there la sufficient occurrcnce in dricking taken in western Canada in 1878 were subs titu I i on s in Salmonella lyphimurim water, a regulation will be proposed. 1,2- found to contain 2,4-D levels above 0.1 and induces sister chromatid exchanges Dlchloropropane le classlfled as a ug/m? or chromosome aberrations in Chinese possible carclnogen and an RMCL of e 2,4-D has been detected in drinking hamster ovary cells, with or without SO pg/l is proposed, based upon the water in four States. In the NORS,one

S-074999 0092(0JW 12-NOV-BJ-I5:2J:34)

F4701 rev. , 8-14-85 Federal Regleter / Vol. 50, No, 219 / Wedneeday, November 13, 1885 / Propoecd Rulee 48993 la4e surface water system was found to were determ ned for the child and the can be applied lo derive ii PfoViHiiinal contain detectable levels of Z4-D (0.04 adult, respertive!y. AADl of 0.35 mR/I. UR/I.In the NSP, once surface water An animr.1 dudy (Rowe. V.K. and T.A. 2.4-D may have mutagenic Hclivily in system contained Z4-D (1.1 ug/l). None Hymas, 1Nd. Summary of Toxicological certain systems; however. the Ri!iiaral of the surface water sy~temssampled Informat'o.1 on 2.4-D and 2.4,5-TP lack of poeitive genotoxic effects in vivo uring the RWS contained 2.4-D in excess Herbicides and on Evaluating the for mamma;ian assays may indiciite that of the minimum quantification limit of Hazards to Llvestock Associated with sufficient levels of 2.4-D are not iililc to 0.01 ug/l. National compliance reports Their Use. Am. J. Vet. Res. 15:622428) reach the target tissues. No informiition for surface water systems sampled for wae used to develop 15 day is available on mammalian multqcnicity 2.4-D were below the MCL asseaamente. In this study, investigators testing conducted with catern of 2,4-D: Concentrations of approximately 0.025 administered 0,100, 300 or loo0 ppm 2,4- these forme could lheoreticaiiy nhiiw ug/l2,4-D have been occasionally D in the diet to group of five young higher levels of penutration iiitii IJirgi!t detected in public water supplies by female rats for 114 days. If it is assumed cells. State agenciee. 2.4-D was detected in that young rate consume 10 percent of Available data from Iiiboriitory 2.4% of surface wntcr monitoring their body weight in food per day, the animals have not provided H 8uffii:icnt stations in the USGS/EPA Pesticide corresponding daily doaen would be 0, demonatrution of carcinogenicity of 2.4- Monitoring Network. 10,30 and 100 mg/kg/day. No effects D. although increaeed tumor production 2,4-D has been detected in many (same parameters as in the 4 week la suggested. This questionn crinnol bi! surface and ground waters. The gavage study) were found at 10 or 30 adequately resolved until more compound hns been detected in waete mglkglday, but 100 mg.kg/day produced compelling evidence is iivuiiiil)ii! from waters and hazardous wastes. is mobile "excessive mortality" with depressed well deaigned bioasanys. 2.4-1) h.,iq . t ii!r!n and widely ueed on many crops. growth rate, slightly increased liver classified in EPA'a Group D. iiccording There are insufficient data available weightn and slight cloudy swelling of the to EPA's Proposed Guidclincs far to make reliable estimates of total liver. Using a NOAEL of 30 mg/kg/day. Carcinogen Risk Asseasmenl. bilsi!d human intake of 2,4-D from drinking an uncertainty factor of loo0 based upon upon inadequute dutn from iiriimni water. food, and air. Assuming that an animal study and consumption of 1 sludiea. drinking water concentrationn vary from liter (child) and 2 liters (adult) of water EPA's MCL for 2.4-D in drinkiiiR 0-10 ug/l, and assuming that air levels per day, 10-day assessments of 0.30 mg/l water, under the National Intorim range from 0.0014.05 ug/m? the and 1.1 mg/l were determined for the Primary Drinking Wuter Reguliilions. is estimated total intake from these two child and adult. respectively. 0.1 rng/l. This standard is bused upon a sources could range from 0.00033-0.45 The NAS (??inking Wafer and NOAEL of 8 mg/kg/day, an uncertainly u /kg/&sy for the adult male and from Ilealfh,1977. Vol. I) has calculated an factor of 500 and the ussumplion that 20 ObO2~/54uglkglday for the formula AD1 for 2,4-D based upon a 2-year percent of the total intake is vin drinking fed infant. feeding study (Hanmon, et el. 1977. water. New studiee have deter.niried a Health Effecle. Short-term exporsure Toxicology and Applied Pharmacology NOAEL at 1 mg/kg/day. lo 2.4-D at high dosee by the oral route 2022-128) in doge in which 12.5 mg/kg/ Exposure to 2,443 at high dosa levels or injuction by various routes resuli in day wae selected as the NOAEL. Using results in kidney damage and skeletal progressive symploms so muscular this NOAEL, an uncertainly factor of muscle changes. It has also Iicen incoordination, hindquarter pardyeis, loo0 baaed upon an animal study and detected in drinking water. Therefore, etuycrr, coma and death In anlmals. aasumption of an average daily intake of an RMCL will be proposed based upon One-day asaeesments, were derived 2 liters of water per day, an AD1 of an AADl of 0.35 mg/l for non- from an animal study (Hill. E.V. and H. 0.0125 mg/kg/day wae calculated. carcinogenic effects. ussumin8 20 Carllale, 1947. Toxiclty of 2,4-D for lnconsietenciea and inadequacies in percent cf tot111exposure is via drinking Experimental Animale. J. Ind Hyg. the 2,4-D toxicity data base have been water. An RMCL of 0.07 mg/l is Toxicol. 2(1:85-95). In this experiment, recognized by both EPA and its proposed. groupe of six guinea pige that were Scientific Advisory Panel. For example, 11. Eplchlorohydrin administered 10 doeee of 50 or 100 me/ the inconeistencies consist of varying day 2.4-D sodium eolt by gavage for 12 effects men at different dose levele in Epichlorohydrin (I-chloro.2.3- days did not develop characteristic different studies. In order to reeolve the epoxypropane; CAS d 106-8!l-8) is ii evidence of inioxication (Le).. muscular inconeistencies and inadequaciea. the halogenated alkyl epoxide. It is solut)le signe) or mortaiity. If it is assumed that Agency ha8 taken action under FIFRA in water (6.6 x 10' mgll) and orRanic the guinea pigs weighed 0.3 kg (the 3(c)(2)(B)to require 2,4-D regletrants lo solvents. A large fraction of the reported approximate weight in the update and complete the 2,4-D toxicity epichlorohydrin supply is uscd to make single dose studies), the NOAEL of 50 data base. Some of the required studiee glycerin. Other applications include: use mg/day correeponds to a daily dose of have been completed and some are as a major raw materia.1 for epoxy nnd 188.9 mglkglday: the equivalent dose of ongoing. A8 a result of the Paiiel's phenoxy resine and flocculunls 2,r .D acid le 126.3 mglkglday. Although recommendations. and the 3(c)(2)(B) (snmetimee used in the production of eymptome w eigne of intoxication were notice, a Wdey range-finding study was potable water and foods). solvent for not specifically aseociated with this performed as a preliminary to a &year resins, gums, celluloae esters and elhers. expoeure. these criteria of toxicity are feeding study. The range-finding study Iiaints. varnishee. nail enamels and still too inseneitive to luetify uning 126.3 (Document Acceseion No. 251473) lacquere (sometimes used to coril mg/kg/day as an animal NOAEL. Using identified a NOAEL of 1 mg/kg body interior8 of water tanka and pipca): 126.3 mglday as a LOAEL, an weight with the liver and kidney as cement for celluloid; curing for uncertainty factor of loo0 based upon an target organs. Preliminary data from the propylene-based rubbers; and use as a animal study with a LOAEL and chronic study eupporl the 1 mg/kg high wet-strength resin for the paper consumplion of 1 liter (child) end 2 liters NOAEL. Assuming that a1 the end of the industry. (adult) of water per da &year experiments there is no change in Analytical Mefhods. Ana I y Ii CH I aseessmente of 1.1 mgl;.sl;lddsl85 mg/l the NOAEL. an uncertainty factor of ?00 methods available for analyzing

5074999 ~~~)(OS)(I~-NOV-~~-IS:~S:~U) F4701 rev. 6-14-85 46904 Federal Reglsler I Vol. SO, No. 218 1 Wednebday, November 13, 1985 I Proposed Rules

epichlorohydrin in drinking water The NAS (Drinking Water and forestomach in a study In which rats Include the dlrect Injectlon gas Health, 1980. Vol. 111) has cited a were given drlnking water containing 0, chromatography technique. threshold for odor perceptlon of 375,750. or 1500 mg/l eplchlorohydrin hman Exposure. No amblenl epichlorohydrin of 0.6 to 1.0 mg/l and a for 81 weeks [Kawabala. A.. 1981. monitoring data are avallable on human threshold for irritant action of 0.1 mR/I. Studies on the Carcinogenic Activity of intake of epichlorohydrin from ambient A human study (Fomin. 1966. Blological Eplchlorohydrin by Oral Add*'stratlon air, food or drinking water supplies. Effects of Eplchlorohydrln and Its in Male Wistar Rats. J. Amer. ked. I lowever. cplchlorohydrin emissions Hygienic Signlficance as an Aasoc. 32270-280). The CAC rlsk and public exposuro levels were Atmospherlc Pollutant Gig. Hyg. Senlt. estlmate is shown in Table 13. estimated by EPA's Office of Air Quality 31957-383) reported an odor threshold The CAG has also calculated risk PlanninR and Standerds. based upon of 0.3 mg/ma for the most sensltive estimates (95 percent confidence limits) pliinte that manufacture or use sub ects and a subthreshold level of 0.2 from lifetime exposure to IO pg/1 cplchiorohydrin in the production of mg Im? epichlorohydrin using several different Rlycerln. epoxy and polyamide resins, A provlsional AADl was calcula led models. These estimates are as follows: elastomers and surfactants. A human for epichlorohydrin based upon an cxponure model WRB employed, based inhalation study in which male rats upon e 50 km radius oround each were exposed lo 100 ppm cpichlorohydrin facili ty, whlch epichlorohydrin 8 hourelday for 30 days estimated then approximately 60 and 10 or 30 ppm e ichlorohydrin e persons are exposed to a concentration hours/day. 5 daysrweek for the Ilfetlme of 8 pR/mJor greater. approximately of the rats and inflammation changes In 10 poll 28810 1 34110 C 1 0 1,OO persons are exposed to a the respiratory tract and kldney lesions I i concentration of 1 pR/ma or greater and were observod [Laskln. S.,A.R. epproxlmiiloly 70,000 personn aro Sellaklrmar, M.,Kuschnar, N. Nelson, S. The avallable data indicato that expoaed to a concentration of 0.1 ug/ma LuMendola, G.M. Rusch. et al., 1980. epichlorohydrin has carclnogenlc effects or greater. Inhalation Carclnogenlcity of In anlmals. For thls reason and because Epichlorohydrln is a contaminant of Epichlorohydrin in Noninbred Sprague- it is likely to be occurring in Jrinklng polymers used in the clarification and Dawley rats. j. Natl. Cancer Inst. 85:751- water due to its use in coatings for storage of potable water and in food 757). Using 2.18 mg/kg/day, as derived drinking water pipes, regulation is processing. It has been detected in from the 10 ppm exposure level, as the proposed. The RMCL will be based upon waste and is considered mobile In LOAEL. an uncertainty factor of IO00 carcinogenic effects and an RMCL of water. and consumption of 2 liters of water per zero le proposed. Heolth Effects.Epichlorohydrin Is day, a provlsslonal AADl of 0.078 mg/l 12. Ethylbenzene rapidly absorbed following oral, dermal was calculated. or inhalation exposures. The NAS (Drinking Water and Ethylbenzene [CAS 1L 10041-4) is a Epichlorohydrin accumulates In the Health, 1980. Vol. Ill) calculated 1-day flammable liquid. soli:ble in water (152 kidneys, liver. pancreas. spleen and and 7-day SNARLS for epichlorohydrin mg/l) and in alcohol, benzene. ether. adrenal8 and is excreted vla the urine but did not calculate an AD1 or cancer acetone and other organic solvents. In and respiratory tract. rlsk numbers. 1982, the U.S. production totaled Following acute exposure lo Epichlorohydrin has been found to be 8,858,241,000 pounds. The primary use of epichlorohydrin. toxic effects in the mutagenic in a number of prokaryotic ethylbenzene is in the production of central nervous nystem. lungs. liver and systems and eukaryotic cell cultures. styrene. kidneys have been observed. At the site Negative results were reported for the Analytical Mefhod. Ana I y t i :a I of application epichlorohydrin is a mouse dominant lethal assay and method available for iinalyzing strong Irritant. The major target organs micronuclcus assay. ethylbenzene In drinking water include for toxicity following chronic exposure Epichlorohydrin has been found to be the purge and trapgas chromtltography to rplchlorohydrln are the nasal carclnogenlc followlng oral and technique. turbinates. IunRa, kidneys, male inhalation exposures. Oral exposuie Human Exposure. No data are reproductive organs and the central produced a dose-dependent increase in available on the levels of ethylbenzene nervous system. forestomach tumors characterized as in foods. A short-term assessment for a 10-day squamous and basal cell hyperplasia, Limited data are available on the exposure was calculated based on a squamoun cell papillomas or squamous levels of ethylbenzene in ambient air. study in rets [Van Esch, C.J.1981. cell carc!nomas Inhalation exposure Ethylbenzene levels in ambient air have Ryksinstitute Voor De Volksgezondheld produced squamous cell carclnomas in been reported between 2 pg/rnCS pg/ma Billhoven Rapport. 827805 005) where the nasal cevlties. The IARC have in various areas. antifertility effects were observed in classified epichlorohydrin in Croup 28: Ethylbenzene has been observed in 3 males given oral doses of Inadequate evidence for carcinogenicity out of 466 randomly selected drinking epichlorohydrin for 10 days before in humans, sufficient evidence for water ground water systems. The mean mHting and through parturition of an FM carcinogenicity in animals and sufficient was 0.87 pg/l. Ethylbenzene also was generation. Using a NOAEL of 2 mg/kg, evldence for activity in short-term tests. detected In 3 out of 479 ground water an uncertainty factor of 100, and Eplchlorohydrin has been classified in systems selected non-randomly (0.8%). consumption of 1 Iller (chlld) or 2 liters EPA's Croup 82. according lo EPA's All three positives were from systems (adults) of water per day, a 10-day Proposed Culdellnes !or Carcinogen serving less than 10,090 people. The assessment of 0.14 mg/l for a 10 kg child Risk Assessment, based upon posillve mean was 0.78 pg/l. and 1-day and 10-day assessments of 0.5 results in several sites In rats. Ethylbenzene has been Identified at mgll for a 70 kg adult was calculated. EPA's CAC has derived estimates of one hazardous waste site designated in This assessment Is also consldered risk from daily exposure to complalnts and consent decrees under protectlve for a 1-day exposure for the eplchlorohydrln In drlnklng water based the Comprehensive Emergency chlld and adult. upon the Incidence of tumors of the Response Compensellon and Liability

F4701 rev. 8-14-85 Federal Register / Vol. 60, 210 / Wednesday, November 13, 1885 I Proposed Rules 40995 No. - Act of 1W (CRRCLA) Fnd the Notional pattern, consumption of 2 liters of weter to beehives and storage vaults ond fur Contingency Plan (40 CFR Port 300). The per day factored in, resultin in a termite control. concentrotion of ethylbenzene ranged provisional AADI of 3.4 mgj. Analytical hfefhods.,\ntllytical from 23 m3/' in drinking water to 13 mg/ Ethylbenzene does not appear to be a methods availuble for analyzing EDB in ! in an cquifer. mutagen. bascd upon testing in a liniitcd drinking water include the purge end tlealth Effects. Ethylbenzene is number of assags with Salmonella trapgas chromatogriiphy technique. absorbed readily from the fyphimurium strains. The Humuir Exposure. Ethylene dibromide gas~rointestionalrracts. luiigs and akin carcinogenicity of ethylbenzene has not has been detected in up tom percent of and can be expected to accumulnte in been tested adsquately. A long-term raw grtrin end 8 percent of grain adipose tissue. Urinary excretion of carcinogenicity bioassay has been products at levcls its high as 540 ppb. metabo!ites of ethylbenzene is the initiated by the National Cancer EDB residues also IHV~been detcctcd predominant route of elimination. Institute, but dato are not yrl aveiliible. on up to 5 percent of thu citrus products Ethylbenzene is not severely toxic Ethylbenzene has been classiticd in entering the US. food supply. after acute exposure. Tho major effects EPA's Group D. according to EPA's Ethyicnc dilJromidc hris Iwcn reported following acuto and chronic oxpoRuro Pro2osttd Guidelines for Crrclnogen in ambient uir ussociotcd wit6 the usc of inclvdo livor and kidncy puthologies and hisk Aanesnment, based upon leoded gasoline. The followlng median nervous system disorders. inaiequatc cvidcnce in animals. concentretione wcrc estimritc!d for ICVCIR No adequate dose-response dutn exist ambient H titer quality criterion of EDB in ambient air: riirtil/remotc via the oral route of exposure froan EPA's (U.S. EPA. 1QDo. Ambi-nt Watcr Quality oms. 0.0 ng/m? urban/suburbon areus. which to derivo I-day assessments. Criteria for Ethylbenzene. 440/5-8&048) 20nglm? and source dominated urcuR. Therefore, tho derivation of the 1-day for ethylbcnzene of 1.4 mg/l, bascd upon ng/m3. Concentratiocs of EDB in levels was bascd upon a 100 ppm (435 1.500 thc and an uncertainty factor of typical urban areas ranged from Wt)o mR/m') NOAEL identified in humans TL\' 1OOO. The provisionel AADl was based ng/m3. The highest value dctccted was following R singlo 6-hour inhal-tion exposure (Bardode] and Bardodejova, upon actuul toxicological data with an 240.000 ng/m? identified NOAEL. in contrast to the 1970. Biotransformation of EDB has been found in drinking water Ethylbenzene, Styrene and Alpha- ambient water quality criterion which and ground water in Huweii. Colifornia. Methyl Styrene In Mol. Amer. Ind, Hyg. was based on the TLV which is not South Carolina. WashinRton. Assoc. ].31[2):2OS209). A total mcessarily hcdon a NOAEL or Conneclicut, Massochusetts. Georgia absorbed dose cf 20.7 mg/kg was toxicology data. and Florida. Two smell community determined, assuming a human The taste and odor thresholds for water supplies in one State contained respiratory inhalation volume of 20 m3/ ethylbenzene in water are 0.1 and 0.2 0.1 and 2.0 pg/l of EDR. Four out of 100 day and an absorption efficiency of 50 mg/l. respectively (Fezzalari, 1678. Odor wells sumpled in another State percent for a 70 kg adult. From this total and Taste Threshold Data, DS.48A. contained EDB at levels ranging from obsorbed dose, a 1-day ossessnient of American Society for Testing and 0.024.10 pg/l. In addition. levels of EDB 20.7 mg/l wits derived for the 10 kg Matcrials. Philadelphia, PA. p. 71). ranging from 0.02-580 pg/l were child, assuming consumption of 1 liter of Ethylbenzene exposure at high dose detected in 25 samples of water water per day. A I-doy assessment of levels results in liver and kidney effects ccilected from wells in a third State. 72.5 mg/l for the 70 kg adult was and the contominant has becn detected Health Effects. EDB hue a high degree derived, assuming consumption of 2 in drinking woter. Thus, regulation is of acute toxicity when administered to liters of water per doy, applying an proposed and an RMCL of 0.68 mg/l is aniinals orally, dermally or by uncertainty factor of 10, appropriate for proposed based upon a provisional inhalation. The target orRans affected use with adequate human dele. AADl of 3.4 mg/l for non-carcinogenic include the lung. liver. spleen. kidney as Because of the lack of appropriate effects assLming 20 percent of the well as the central nervous system. exposure duration data, the 10-day exposure is via drinking water. Repeated exposure to EDE ills0 may affect the liver, stomach und adrenal assessments ore derived from the &day 13. Ethylene Dibromide levels simply by dividing the 1-day cortex along with significtlnt numbers by 10 to give estimated 10 Ethylene dibromide (1,2- reproductive sptem toxicity. The testis values. The resulting 10-day assessment dibromoethane, EDB: CAS sC106-93-4) ISparticularly sensitive to iitrophy arid for the 10 kg child is 2.07 mg/l and for is a pesticide. Most uses of EDB were antispermtitogenic effects. the 70 kg adult, 7.25 mg/l. canceled in 1984. Citrus quarantine and No appropriate dose-re8ponse data A provisional AADl was determined several very minor uses remain are available on non-carcinogenic based upon a laboratory study in which registered. EDB is water soluble (4.500 effects following exposure to ethylene rats were treated orally at four dose mgll) and highly volatile. Recent data dibromide from which a I-day levels, 5 days/weeks for 6 months suggest that EDB has a half-life of assesament or an AADl could be (Wolf, et el. 1958. Toxicological Studies approximately eight years at 20 'C under derived. However, there are data from of Certain Alkylated Benzenes and neutral conditions. More than 90 percent which a 10-day assessment can be Benzene. Arch. Ind. Health. 14:387-398). of the annual total production of EDB is derived. A LOAEL of 7.6 mg/kg/day No observable effects were reported in used as an additive in leaded gasolice. was identified from a study by Eljack the groups exposed at 13.8 and 130 mg/ In addition, EDB has been used as a soil and Hrudka (1979) in which rams kvvare kg/day, while histopa!hological changes fumigant for soybeans, cotton, peanuts. given EDB subcutaneously for 12 were evident in groups treated at 408 pineapples and many othcr fruit and consecutivo days. Applying H scries of and 880 mg/kg/day. A NOAEL of 138 vegetable crops. EDB had been used in uncertainty factors which total loOD0 to mglkglday was identified, with an poebharvest Fumigation of stored grain accommodate for intra- and inter- uncertainty factor of IO00 based upon an and spot fumigotion of grain milling species extrapolation (100).convcrsion animal study of significantly less tnan machinery. Other uses have included of a LOAHL to a NOAEL (ln)end the lifetime duration and a factor of 5/7 to the fumigation of field logs and the potential that the human is closer in convert from a 5 day/week dosing quarantine fumigation of citrus and sensitivity lo the bull than the ram (io). regimen to a 7 daylweek exposure other fruits and vegetables. application and nnsuming that the 10 kR child drinks

Sa74999 009#05XIZ-NOV-8S- t5:25:4t) F4701 rev. 8-14-85 46990 Federal Register / Vol. 50, No. 219 / Wednesday, November 13, 1985 I Proposed Rules - 1 liter of water per day, a Io-day assume consumplion of 2 liters of water samples, 50 percent of the meat. fish and assessment of 0.008 mg/l is derived. The er day by a 80 kg adult. over a 70 year poultry samples. 5 percent of the oils equivalent Io-day aesesament for a 70 kg Pifetime and are derived from the qestric and fats samples. 5 percent of the root adult woiild be 0.027 mg/I. tumor responne in mele rats in the vegetable samples. and 5 pwccnt of the Since there are no duration-specific National Cancer hitilute gavage study. oils and fats semplrs. 'The range of data aveilablc from which to derive a 1- Subsequently, CAG (1984) modified positive values for heptachlor epoxide day assessment. it is recommended that these eetlmates to determine risks posed was 0.2-2 pg/kR. In the infant study. the 10-day assessment be used for 1-day in drinking water to a 70 kg adult. heptachlor epoxide was detected in 50 as well. consuming 2 liters of water per day from percent of the whole milk semples. 50 EDB has been shown to be mutagenic age one to age 78. percent of the other dairy and in vitm in bacteria and eukaryotic cells. The NAS (1980) and CAC (1984) rink substitutes samples. and 70 percent of Limited evidence suggests that EDB may estimates are shown in Table 13. the meat. fish. and poultry samples. 'The causc clastogenic effects such as sister The available data indicate that ED6 range of positive values was 0.2-1 pR/kR chromatid exchanges. chromosomal has carcinogenic effects in animals. It for heptachlor epoxide. In the toddler aberrations and polyploidy. has also been found in drinking water studies for fiscal year 1879. heptachlor EDB has been demonstrated to be a md therefore it will be regulated. The epoxide was detected in 50 percent of potent carcinogen in rats and mice RMCL will be based upon ice the whole milk samples, w percent of exposed via gavage and inhalation. The carcinogenicity and tin RMCL uf zero is the other dairy and substitutes samples. IARC have classified EDB in Group 28: proposed. 70 percent of the meet. fish. and poultry inadequate evidence for carcinogenicily 14. Heptachlor and I leptachlor Epoxide samples. and 10 percent of the oils and in humans. suftlcient evidence for fats samples. The range of positive carcinogenicily in animals and sufficient Heptachlor (1,4.5,8.7.8.8'-heptachioro- values of heptachlor epoxide in this evidence for activity in short-tcrm tests. hanoindene; 3a.4,7,7a-tetrahydro-4.7-met study was 0.2-20 pg/kg. The U.S. EDB has been claesified in EPA's Croup CAS S70-444 expoxide CAS WOZe Department of Agriculture reports that B2. according to EPA's Proposed 57-3) is an insecticide. Technid grride 4.7 percent cf fat tissue samples from Guidelines for CarcinogLn Risk heptachlor la a waxy subst: ice which various animals intended for human Assessment, based upon positive results contains chlordane and has a water consumplion werP found to contain solubility of 0.058 mg/l et 25 'C. in studies in rats and mice. heptachlor in the range of 100-5.000 )IS/ Administration of EDB to rats and Heptachlor rapidly oxidizes to the kg. although the majority of positive mice by gavage for 4961 weeks epoxide 1.4,5.e.7.8.8'-heplachloro-~,~- produced significantly increased epoxy-3a.7.7a-tetra hydro-4.7- value3 were in the range of 10-100 pg/ incidences of equamoue cell carcinomas methanoindene, which is more stable kg. of the forestomach. hemangiosarcomas and more presistent. Moet registrations Milk supplies have on occaeion been of the circulatory system, hepntocellular of heptachlor were suspended in 1978. found to contain heptachlor epoxide carcinomas and liver neoplastic Prior to 1974. heptachlor was widely above FDA's action !$vel. Samples of noduiee. [NCI. 1978. Bioassay of 1.2- used for control of termites. ants. soil human milk collected in the mid-1970s Dibromoethane for Possible insects in agriculture and various insects were found to contain heptachlor Carcinogenicity. NCI Carcino. Tech. and on gardens. lawns. turf. and epoxide. In 1980-1982, the Oahu milk Rep. Ser. Co. PB 2888-428). Chronic ornameiilals. Heptachlor was used supply was extensively conlaminated by inhalation exposures produced extensively lor the protection of corn heptachlor epoxide. The levels exceeded significantly increased incidences of crops in Ohio. Iowa. Missouri. Illinois 1 ppm in the milk fat and typically nasal cavity tumors in rats of both and Indiana. exceeded the action level. sexes. alveolnr/bronchiolar carcinomas In 1974. EPA issued a Notice of Intent In a 1970-72 EPA study of levels of or adenomas in mice and nasal cavity to cancel all registered uses of heptachlor in the ambient air of le U.S. lumors in female mice. (NTP. 1982. heptachlor except for subsurfece control cities. the maximum level measured was Carcinogenesis Bioassay of 1,2- of termites end dipping of roots and tops 27.9 ng/m? The mean va!ue for all Dibromoelhane in F344 Rats and Ib6Fl of non-food plants. In 1978. EPA iesued a posltive samples was 1.0 ng/ms. Mice (Inhalation Study) NTP-80-28). final order cancelling all registrations of Heptachlor was detected in 42 percent Significantly increased incidences of heptachlor subject to the 1974 Notice of of the 2,470 samples collected during the circulatory system hcmangiasarcomas, Intent to Cancel. Currently, heptachlor is monitoring period. pituitary adenomas. tunica vaginalis registered only for subsurface control of The results of the Suburban Air niesothcliomas and subcutaneous subterranean tennitee and dipping of Moniloring Program conducted from fibrosarcomas also were found in thc roots and lopn of non-food plants. April to lune 1975. showed that all five study. Analytical Methods. Analytical samples collected from a city in Florida Tne NAS (Drinking Woler and methods available for analyzing were found to contain heptachlor with a i/ecolfh,1980. Vol. 111) calculated excess heptachlor in drinking water include the mean concentration of 2.1 ng/m'and a cancer risk estima 2s for EDB. This solvent extraction-gas chromatography maximum value of 3.8 ng/m? All five estimate was based upon the results of a and solvent extraction-gas samplee collected from h city in report (@Ison,el al. 1973. Induction of chromatographylmass spectrometry Mississippi were found to con:ain Stomach Cancer in Rata and Mice by techniques. residues of heptachlor. The sample Halogcnated Aliphatic Fumigants. 1. Human Exposure. In FDA's mean was reported as 10.9 ng/m? with a Natl. Cancer Inst. 51:1993-1995) which compliance program report for fiscal maximum reported value of 22.1 ng/m'. deswibes the results of the bioaesay year 1977 on pesticides and metals. The maximum level of heptachlor conducted by NCI. EPA's CAG (1983) heptachlor epoxide was detected in 4.7 detected in analysis of weekly air also has estimated lifetime cancer risks percent of the samples tested. In the eamples in the Miseiesippi Delta during for EDB in ground water. These risks FDA fiscal year 1979 total dietary study 1972-73 was reported as 0.8 ng/km? were calculated from a model that is for adults. heptachlor epoxide, the ifeptachlor has been reported in eseentially the one-hit model with mecabolite of heptachlor, was detected drinking water. Three wells in one State "Weibull ' timing. These estimated rlsks In 85 percent of the dairy products were found to conteln heptachlorr the

F4701 rev. 614-85 ranRe of positive values was O.OI-I.O (1.5 ppm) wuidentified tin ri Iowt!st mi,e in thi! S..iioniti (;i:nf.tsr Institute PR/I.A rural water supply study effect level causing incr-Jscd Iivc:, Liniissiiy. ’I+,! SiIS IDr//tA,:t,g ll’iI/cr ‘~’II. conducted in another State showed that weights of nnitiials. Using 0.075 rn;;/hs/ It4:uirh. IS:. Vol. I)hits illSlJ e!s\bm;t~*:tl 62.5 percent of the samples taken :n one day ns the LOAEL. iin uncertr;niy liat:tl)* ciinccr risks. Thi! (AL iind SAC, till-time county and 45.5 percent the samples of IO00 based upon ;in nnimat study ii:iti risk i,.etim;itrs iirv shown ill ‘I ii1111+]:I. taken in atiother county hud consumption of 2 litrrs of watw pcr c!iiy. l‘hr IAKC hil\.P clcissifiwJ I\i~ptii(;hlo~ill concentrations of heptachlor above 0.01 n provlslonlil AAIII of n.(X125 mg/I WHS Croup :I: inadi!qiIiitc cviclriiw of PdI. calculn tcd. l:ilrc:inOgc~lc:it\ iri tiurnails ;ind Itmiti-;I Two out of 22 tap water samples For heptachlor epo :idc. H provisionirl cviclcnw ti! c:;ircinogcnicit\ ‘11 ,II’ ::iiBls. collected in another Stnte reportedly ANI1 was derived Iiased upon n two. I leptachior h,ls Il+!en diiss~I~,~,iin El’:\’s were found to contain heptachlor at ycar oral study in dogs (Unpublishrd. Grorig R2. accord ny 111 Elb,\’c l’r~>pos~~il levels between O.OOM.~!~ pg/l. IRDC. 1971. Two-yecir study Orel Study hid-lines for Ciircinogiin Hish Heptachlor has been identified at two in Beagle Dogs) where 0.325 mg/kg!d,!. AsSessT(!nt. t)iisco upln luisitit t. ~I:SII~I~ hnrnrdous waste sites designated in (1 ppm) was identified as the NOhEI.. in stuuii*s in micv. complninls Rnd consent decrws under Using 0.025 mR/kg/cliry as the NO:\El.. EPA’~C,‘ <; hiis iilso dt:i I\-t!d IIsk the Comprehensive Emergency an unccrtn,inty fiictor of for nn es!.ntates from d:iily CX~(J!.~IICti) Response Cornpetvation cind Linbility at-imal study of less then lifetime hcptachlor c\poxitl(: in drinkinR wutcr Act of 1980 (CERCU, and the National duratii-I und Lunsumptton of 2 littrrs of hirsed iir~onil hdlng stutly in f(!niiilf! Contingency Plnn (40CFR Part 300).The water I er day. a provisioniil AhDl of rats !iVithcrup. et al. 1~18.Xie concentration of heptachlor rnnged from 3.001 mg/l w,lr( calculuteti. Phy~iolii~icalEl’fects 01 thIntroduction undetermined in miRretinR Rround I leptachlor has bccn ttntid for of I lc-pt,ic;h:or Epo\iclc in l‘iiryiiig 1.vt cila wrlter, 3tl p~/lin soil to 4000 p~/lIn mutripenlcity in II number of systems. of Conc:entriit.on into the lhtof sediments. LFK NeRelive results hate heen obtainvti in Hats. Unpublished report citibd in ffea’thEffects. Heptachlor epoxide is the bacterial nss~yin fruit flies, for Epstein. 1976. Sci. Total Erit iron. G:lO3). the major metabolite of heptachlor iind unscheduled DNA synthesis in rats. The CAC; risk estimates are shown in is distributed to tissues of animals. with mouse and hamster primary hepatoc:yte Talilc I:]. The IARC hiive not cliissificd the highest levels detected in adipose cultures and fur the dominiint lcthirl hcptiichlor epoxidc for carcinogenicity. tissue. Symptoms of acute heptachlor nssay in mice. Positive results were I icptiichlot csposide hiis iilso IIWZ intoxicelion include central nervous r,ported for unscheduled synthsis l)Nt\ clitssified in EI’A’s Croiil~132. based system disturbances such as tremule. in transformed humiln lihrotiIiistQwith convulsions, paralysis and hypothermia. upan posititr results in sthvliesin micr <.-Q nctivation and in the dcminant end rats. Lower doses result in microsomal lethal dssny in rats (Cerey. et al. IGJ. The LVtlO recommendsl an All1 enzyme inrluction. hyperplasia hepatic Effects of I leptachlor on Dominant vein thrombosis and cirrhosis in mice. hthdity and Done-htiirrow in Rats. value of 0.5 pg/kg ~JWf1.r hvptac:hlor or hop I ii ch Ior e pox ide. 1‘h is Ten-day assessments for heptachlor Mutat. Res. 21:20). recommendetion WHS f!stiihliShed by the were derived based upon rl feeding Heptachlor hris henstudied for study (Enan. et al. 1982. Effects of Some carcirogenicity in mice and rats. In one joint FAO/iVI.IO Expcrl Comniittt!e on Chlorinated Hydrocarbon Insecticides study. statistically significant increu--d Food i\dditives. A guideline value in on Liver Function in White Rats. Meded. incidences of hepatic carcinoma were driphtng water (1981) olO.1 pg/l was Fac. Landbouwwet. Rijksuniv. Gent. determined in a study of heptachlor also rrcommendpd by the WHO.based 4711):447) in rats for 14 days where a epoxide at 0. 0.5. 2.5. 5.0. 7.5 and 10.0 upon this level as one perccnt of the level of 1.0 mg/kg/duy (10 ppm) resulted mg/kg diet in rats fnr 108 weeks ADl. A detection and odor threshold in definitive adverse effecte (Le.. [Withemp. et HI.1959. The Physioli)gical value of 0.02 mg/l has been reported in evidence of liver damage arid altered Effects of the Introduction of tieptnc:hlor the literature lor heptachlor. liver function). Uelng 1.0 mg/kg/day as Epoxide in VH~YIFR1,evels of The available data indiciite that the NOAEL an uncertainly factor of Concentration into the Diet of CFN Rets. heptachlor and heptachlor epoxide have loo0 based upon an animal study and Unpublished report cited in Epstein. carcinogenic effects in animals. Since consumplion of 1 liter (child) or 2 litera ‘976. Sci. Total Environ. 6103). in a heptachlor epoxide is coilsidered to be il of water (adult) per day. IO-day National Cancer Institute bioassiiy (NCI. major metabolite of heptachlor and asseeements of 0.01 mg/l for a 10 kg 1977. Bioassay of lleptachlor for because they have been detected in child and 0.035 mg/l for a 70 kg adult Poe: !ble Carcinogenicity. NCI drinking water. tlxy are proposed for were calculated. Carcinogenesis Tech. Rep. Ser. No. 9). regulation. An RMCL of zero is proposd There arc insufficient toxicological male mice received dietary for both heptachlor end heptiichlor data available to derive a 1-day concentrations of 0. 6.1 and 13.8 mg expoxide. assessment fnr heptachlor: however it heptaclilor/kg diet and female mice Question for Comment: ehould be noted that the 10-day numbers received diets containing 0. 9.0 and 16.7 1. Shoiild ,. single RhlCL or two would also be protective for the I-day mg/kg diet. The incidence of indivitlual RMCLs be proposed for exposure period. Insufficient data are hepatocelluler carcinomas was hcptnchlor and its melribolite heptiichlur availoble to derive I-day or Io-day statietically significttnt in the males. woxide‘t numbers for heptachlor epoxide. while a highly significant dose-related 15. Lindane A provisional AADI for heptachlor trend was also observed between high- was derived boeed upon a feeding study and low-dose females. Heptachlor was Lindane (gamma is isomer of (Witherup. et el. 1955. The Physiological not carcinogenic in male and female rats 1,2.3,4,~,6-hexachlorocyclohexane;CAS Effects of the Introduction of Heptachlor similarly treated with concentrations of sr 58-89-9; current MCL is 4 pg/l) is an into the Diet of Experimental Animals in 25.7 to 77.9 mg/kg diet. insecticide registered for commercial Varying Levels of Concentration. EPA’s CAG has derived esthetes of and home use. Lindane is the acfive unpublished repnrt cited in Epstein, risk of daily exposure to heptachlor in ingredient in several prescritled 1976. Scl. Total Envlron. 8:103) in rates drinking water based upon the incidence shampoos used for the elimination uf for 110 weeks where F.075 mg/kg/day of hepatocelbldr carcinomas in male head lice, Similar preparations are

F4701 rev. 6-14-85 46B98 Federal Register I Vol. 50, No. 218 / Wednesday, November 13, 1985 1 Proposed Rules

avoilable for the elimination of fleas end of lindane, with a mean !we1 of 0.1 ne/ adult are recommended for use for 1-day lice on pets and farm animals. ms and a maximum level of 1.6 ng/mJ. assessments. Ihdune is slightly solubln In water Low levels of lindane have A provisional AADI was calculaled (7.8mg/I at 25' C). Despite a low vapor occeslonally been found In drinking for lindane based upon a feeding study prcssure, lindane will volatilize to the water. It has been found in drinking (Research Consulting Co. Ltd., 1983. OPP atmosphere from soil or water. It is water in at least four States. In the Support Document) in which male and persistent In soils [half-life greater than National Organics Reconnaissance female rata were fed pure lindane In the 100 days), though it does undergo rapid Survey (NORS), two out of eiRht surface diet at levels of 0,0.2,0.8.4.20and 100 biotransformatlon under anaerobic water systems contained llndane (0.01 ppm for 84 consecutlve days. Liver conditions. pg/l end trace). hypertrophy, kidney tubular Analytical Methods. Anayltical National compliance data show that degeneration, interstitial nephritis and methods available for analyzing lindane no surface or ground public water basophilic tubules and other effects in drinklng water include the solvent eystems In the U.S. were reported lo be were seen at the 20 and 100 ppm levels. extraction gas chromatography In violation of the MCL for lindane. Effects were rare and very mild at the 4 technique. In the Rural Water Survey (RWS) 1 ppm level. Using 0.8 mg/kg/day (4 ppm) Mmon Exposum. In 1977, the FDA out of 71 ground water systems as the NOAEL, an uncertainty factor of rcpotted findlng lindane residues in 2.1 exceeded the minimum quantification lo00 baaed upon an animal study of percent of the food samples tested. In limit (0.002pg/l) for lindane. In the short duration and consumption of 2 the 1979 toto1 diet study, FDA reported NORS, water samples from the two liters of water per day, a providonal lindone in 12.7 percent of adult food ground water systems sampled AADI of 0.01 mg/l was calculated. contained lindane, but the levels were snmplea with concentrations ranging Lindane has been tested for from trace to 8.0 pg/kg in bugar, meat, below the minimum quantifiable concentretion. carcinogenicity in laboratory animals. fish, poultry, grains, cereal, vegetables Thorpe and Walker (1973,Food and and garden fruit. In the same year, Local conditions can lead to drinking 2 water contamination. A rural water Cosmel. Toxicol. 11:433442)reported a percent of the infant food samples and eignlflcant increase in liver tumors in 14.7 perceii: c!! !cSG!er food samples c up ply study in one State reported that 58.3 percent of samples contained levels the treated mice relative to the controls were positive for lindsne. with (96% in treated males and 85% in treated concentrations ranging +om 0.2 to 2 pg/ of lindane greater than the detection limit of 0.01 pg/l. females, compared to 24% and 2376, kg and from 0.2 to 5 pg.kp, respectively. respectively, in the controls). In Tolerances for residues of lindane Lindane has been ldentinkd at five hazardous waste sites designated in addition, there was evidence of tumor established by the EPA's Office of metastases to the lungs in both sexes. In Pesticide hograms in or on raw complaints and consent decrees under (OPP) the Comprehensive Emergency 1977, the NCI (Technical Rep. Ser. No. agricultural commodities are given Response Compensation and Liability 14) published the results of a lifetime below: bioassay of lindane in mice. The Seven parts per million in or on the Act of 1980 (CERCLA) and the National Contingency Plan (40 CF'R Part 300). incidence of hepatocellular carcinomas fat of meat from catllc. goats, horses, Health Effects.Ai rte exposure of In low dose (60 ppm) males was and sheep. animals to lindane results in significant when compared to pooled Four parts per million In or on the neurological end behavioral effects. controls, but not in the high dose (160 fat of meat from hogs, Subchronic and chronic studies have ppm) males. The evidence indicates that Three parts per million in or on shown a variety of effects, including lindane is carcinogenic to mice when cucumbers. lettuce, melons, mushrooms, liver hypertrophy, kidney tubular administered orally, producing liver pumpkins. squash and tomatoes. degeneration and Interstitial nephritis. tumors. The IARC have classified One part per million in or on apples, The liver and the kidney appear to be lindane in Group 3; inadequate evidence apricots, asparagus, avocados. broccoli, the primary target organs for lindane for carcinogenicity in humans, limited brussel sprouts. cabbage, cauliflower, toxlcily. evidence for carcinogenicity in animals celery, chcrries. collards, eggplants, Insufficient data are available to and inadequate evidence for activity in grapes. guavas, kale, kohlrabi. mangos, derive a one-day assessment for short-term tests. EPA's Office of mustard greens, nectarines, okra, onions lindane. A 10-day assessment was Pesticide Programs has stated, "Using (dry bulb only), peaches. pears. pepper, based upon a study (Muller. et al. 1881. the new Proposed Guidelines for pineapples. plums (fresh prunes), Electroneurophyslological Studies on Carcinogen Risk Assessment (cited , quinces, spinach. strawberries rnd Neurotoxic Effects of above), the CAG has classified lindane Swiss chard. Hexachlorocyclohexane isomers and as 'B2-C' (Le., in between the lower half A U.001 part per million (negligible gamma-pentachlorocyclohexane. Bull. of the '8' category of 'probable' and the residue) in or on pecans. Environ. Contam. Toxlcol. 22704-708) In 'C' category of 'possible' carcinogen The USDA notes that 0.1 percent of which decreased motor conduction classifications) based upon evidence swine samples vioiated allowable velocity was detected In the tail nerve of that lindane gives rise to malignant liver lindane concentralions in a 1980-1983 rats fed lindane for 30 days at 25.8 mg/ tumors in two strains of mice, plus monitoring study. No lindane residues in kg. Ten-day values of 1.2 mg/l for a 10 supportive evidence of pre-cancerous excess of the to!erance were found in kg child and 4.3 mg/l for a 70 kg adult liver lesions in shorter term studies." other meat products examined. were calculated from a NOAEL of a 12.3 This weight of evidence classification In a 1970-1972 EPA study of 18 US. mg/kg, with an uncertainty factor of 100 also included consideration that, on the cities, lindane was detected in 88 based upon an animal study and one hand, at least one study was percent of the ambient air samples. The consumption of 1 Iller (child) or 2 liters positive in both sexes and a lindane positive mean value was 0.9 ng/mJ and (adult) of water per day. metabolite has been shown to be the maximum value reported was 11.7 In the absence of an appropriate oncogenic, while, on the other hand, and ng/mJ. In a 19w) EPA study monitoring toxicological data base for a one-day leanlng the classification toward class IO locations in the U.S., 0.8 percent of assessrn?nl, the ten-day values of 1.2 "C", lindane has not been shown to be the atlmples contained delectnble levels mg/i to: the child and 4.3 mg/l for the mutagenic afler extensive testing and

SO74999 OOVA(06)(lZ-NOV,-85- t5:27:24) F4701 rev. 8-14-85 - Federal Regleter / Vol. SO, No. 219 / Wedneeday, November 13, 1985 / Proposed Rules 48999 none of the oncogenicity studies showed been set baaed upon 1) the AADI methoxychlor In drlnklng water include a dose-response. Therefore, the weight approach using an additional the solvent extrectlon-gas of evidence appears to be closer to a uncertain\,. factor less than 10 due to the chromatography technique. Category C carcinogen than to Category nature of the data, 2) the risk calculation Human Exposure. In the FUA FY 79 82 carcinogen. approach risk), or 3) the rlsk tottll dietary studies for adults, Based upon the carcinogenic effects calculation approach (lO-arisk). methoxychlor was detected in 1 out ol observed In the liver of mice fed lindane An RMCL and primary regulation will 10 dairy products sampled at G pg/kg. and using one of several models bn proposed for lindane because of the Methoxychlor was also detected in 1 nut available, the NAS (Drinkin, Wafer and potential adverse effects and occurrence of 10 whole milk smples at a level of 2 Health, 1977. Vol. I) estimated the in drinking water. Llndane has been pg/kg in the dietary study for infants. possible carcinogenic risk of lifetime classified as a possible carcinogen and Residues of methox) chlor ranging from exposure to lindane for a person tho proposed RMCL of 0.0002 mg/l for 2-8 pg/kg were reported in n whole milk consuming two litera of wiiter per day. lindane le based on a provisional AADI sampie, a sample of the dairy and other EPAs CAC has also derived estimates of 0.01 mg/l for non-carcinogenic effects substitutes, and In a frult iind fruit juicc of poaslble rlsk of daily exposure to and an additional factor of 10, assuming sample from toddler studies. lindane in drinking water. CAC also 20 percent contribution from drinking Compllance reports for FY 78 reveal that based the risk estimate on the her water. methoxychlor was detected in I percent carcinogenicity observed In mice. The Questione for Comment: of domestic food samples teeted. In NAS and CAC risk eatilr.3tes are shown 1. 1s it appropriate to propose an addltlon, methoxychlor levde in in Tab!e 13. AADl for lindane based on a shorter vlolation of the USDA maximum The WHO proposed an AD1 of 0.01 than lifetime feeding study in animals allowable level weft dntectod In 0.2 mg/kg bw and a g!~idelinevalue in (Research Consulting Co. Ltd. 1983)? percent of samples of call lissues for drinking water of 3 pg/L The AD1 was 2. In the background document on 1982-1883. established Ly the Joint FAOlWHG lindane, alternate studies (Fitzhugh, e'. The tolerance levels set by EPA'a Expert Committee on Food Additives al. 1950. The Chronic Toxicities of Office of Pesticide hograms for residues and the guideline In drinking water was Technlcal Benzene Hexachloride and its of methoxychlor in or on raw set at a level of one percent of the ADI. Alpha, Beta and Gamma Isomers. 1. agricultural commodities are given EPAs MCL for lindane in drinking Pharmacol. Expo. Ther. 100:59, and below: water, under the National Interim Rlvett, et el. 1978. Effects of Feeding One hundred parts per mlllion In Prlmary Drinking Water Regulations, is Lindane to Dogs for Periods of up to or 0.004 mg/l. Thls standard is based upon Two Years. Toxicology. 9:273) are cited on alfalfa, clover, cowpeas. grass for a NOAEL of 15 ppm (0.3 mg/kg), with an in the conslderation of an AADI. forage, peanuts and soybeans. uncertainty factor of 500 dnd the Comments are requested on their Fourteen parts pe million in or on assumption that 20 percent of the total appropriateness In the derivation of an various fruits and vegetables. Intake is via drinking water. New data AADI. Seven parts per million in or on indicate that !indene is carcinogenic in 3. Is it more appropriate to classify sweet potatoes and yams from the mouse and this data was not taken lindane In EPA's Croup 82 or Group C? preharvest and postharvest application. Into accc'ilit in the establishment of the On what basis? Three parts per million in or on the interim MCL. 4. If lindane is classified in EPA's fat of meat from cattle. goats, hogs. The available data do not permit Croup C, should the RMCL be based horses or sheep. definitive decisions on the oncogenic upon the AADI approach or the risk Two parts per million in or on the potential of lindane in the rat. The calculation approach? If the AADI following grains from storage-bin Office of Pesticide Programs is requiring approach is used, should an extra treatment: barley, corn, oats, rice, rye. thpt a rat oncognicity bioassay be uncertainty fdctor of 10 be applied or sorghum grain and wheat. performed (OPP, Sept. 30,1085). Until some lesser value? If the risk approach A 1.25 ppm In milk fat reflecting definitlve decislon on the oncogenic is used should be RMCL be based upon negligible residues in milk. potential of lindane is established, the lo-*or 10-arisk level? One part per million in or on lindane will be classifed in EPA's Croup potatoes. C for the reasons outlined by the Office le. Methoxychlor One part per million inor oil of Pesticide Programs, above. Lindane Methoxychlor [(2,2-bis (p- horseradish. has been placed in Regulatory Category methoxyphenyl) l,l,l-trichloroethane; No data are avail~ableon !evels of I1 end the RMCL has been set based CAS # 72-433; current MCL is 100 pg/ methoxychlor in ambient air. upon the provisional AADI of 0.01 mg/l 11, a chemical closely related to DDT, Methoxychlor has not beer1 detected with an additional factor of 10, with 20 has bean used as an insecticide for during national drinking water percent drinking water contribution approximately 40 years. Technical monitoring surveys. Combliance factored in. The proposed RMCL is methoxychlor is a mixture containing 88 monitoring has not reported based upon a feeding study (Research percent of the p,p'-isomer. In 1877, methoxychlor in excess of the MCL. Consulting., Ltd. 1983. OPP Support domestic consumption of methoxychlor However, methoxychlor has beeic Document) in rats. Using 0.3 mg/kg/day was IUmillion pounds. Methoxychlor detected in drinking water in high use (4 ppm) as the NOAEL, an uncertainty has been widely used for home and areas. One state Ltiidy on the effects of factor of loo0 baaed upon an animal garden applications, as well as on forest runoff on the quality nf water study of short duration and consumption domestic animals, tree, and in waters. supply systems observed an ambient of 2 liters of water per day, a provisional The p,p'-isomer is soluble in water to concentration of methoxychlor of 50 pg/ AADI of 0.01 mg/l was calculated. An 0.28 mg/l at 25'C. The half life for 1. In one county, 48 percent of the additional factor of 10 was applied methoxychlor In water is Patimated !o samples of rural water supplies because an order of magnltude be 48 days and thus il la not considered contained detectable levels of uncertainty factor was determined to be to be persiatent. methoxychlor (mean of 0.033 &I): in sufficiently protective for thls chemical. Analyficol Methods. Analytlcal another, 64 percent of the samples we:e Alternatively, the RMCL could have methods available for analyzing positive (mean of 0.023 pg/l).

S-074999 0099(06)(11-NOV-85- 15:27:26) F4701 rev. 8-14-85 - 47000 Federal Register / Vol. 60, No. 219 / Wednesday, November 13, 1986 / Proposed Hules

HeolfhEffecfs. Methoxychlor exhibits under the conditione of the experiments. Methoxychlor has been shown to a widn range of toxicity when A National Cancer Institute bioassay exhibit chronic toxic affe.:ts at high doee administered at high dose levels to (NCI. 1978. Biassay of Methoxychlor for levels and has been deter:,, in drinking animals. Central nervoua sygtem effects Possible Carcinogenicity. NCI-CGTR- water. The Rh4CL will be bab 4 upon were observed in dogs, chrorlic nephritis 35) reported inconclusive resulte. Male non-carcinogenic effects; eeeiii. Ing 20 and cystic tubular nephropathy in swine and female rats were expoeed to percent contribution from drinkiqg and rets, fatty changes in the livers of technical grade methoxychlor in the diet water and based upon an AADll4 1.7 swine and marked testicular atrophy in for 78 weeke. It was concluded by the mg/l; and RMCL of 0.34 mg/l is rats and swine. Hiatopethologic changes investigators that methoxychlor was not proposed. in the kidneye. liver or reproductive carcinogenic under the conditions of the organs were not observed at dietary reported assay. Re-examination of the 17, Monochlorobenzene levcla below 1000 mg/kg. data by an independent pathologlet Monochlorobenzeno (chlorobenzene One-day assesements for indicated that methoxychlor was CAS M0840-7) is a solvent with a methoxychlor were based upon a study carcinogenic in the etudies: however, vapor pressure of 12.4 mm Hg at 25 'C. It Investigating the effects of methoxychlor recent reviews by EPA's CAG in 1984 of is nearly insoluble in water. In 1981. following a single oral dose of 840 me/ the NCI bioassay program 129,500 kkg of monochlorohenzene were kg in ra:a (Morgan and Hickenbottom, recommended that the resulte be produced in the U.S. 1979. Relative Senellivitiee of Various considered neither positive or negatlve, Monochlorobenzene is ured as a solvent Diochemical, Toxicological and but inconclusive. Methoxychlor has in cold cleaning operations and Patholqgical Techniques in been classified in EPA's Group D, peeticide manufacturing. These usee Demonstrating Sublethal Leeions in the according to EPAe Proposed Guidelines accounted for half of its production IF Rat Following Oral AdiliiiMralion of for Carcinogen Risk Aseessment, baaed 1978. Releaees of monochlorobenzene to Low Levels of Methoxychloi. Toxicol. upon Inconclusive results in animal air from production and uee processes in Appl. Pharmacol. 45237). The effects tests. 1978 where eetimated to be 79,500 kkg. observed were decreAsed lactate and Negative results were obtained from a Data are not available on releases to glycogen phosphorylase and increased number of mutagenicity studies in land and water. Quanlitiea of glucoee-tbphoephatase. Ueing 840 mg/ bacteria and yeast, from assays of rnonschiorobenzene entering eurfaco kg/day a8 the LOAEL an uncertainty methoxychlor induced DNA ds:,lags in waters we expected to volatilize to factor of loo0 based upon an animal DNA repair-deficient strailla, from ambient air. Little informationis study and consumption of 1 liter (child) recessive lethal asnayn in Omsophila available on the fate of or 2 liters of water (adult) per day, 1-day melanogaster and in assays of monochlorobenzcne in the atnosphere. assessments of 6.4 mg/l for a 10 kg child unscheduled DNA eyntliubb In Analytical Methods. Analytical and 22.4 mg/l for a 70 kg adult wen3 mcthods available for analyzing calculeted. mammalian cell cultures. EPA's MCL for methoxr :Mor in monochlorobenrene in drinking water Ten-day assessment for muthoxychlor include the purge and trap-gas were based upon a atudy (Stein, 1808. drinking weter, under the National Comparative Methoxychlor Toxicity in Interim Primary Drinking Water chromatography and the purge and trap- Doge, Swine, Rata, Monkeys and Man. Regulations. ie 0.1 mgll. This level was gae chromatography/mase spectrometry Ind. Med. Surg. 37540) in which baaed upon human studies which techniques. volunteers were given methoxychlor st identifiod a NOAEL of 2 mg/kg/day, Human Exposure. Insufficient data levels of 0.5.1.0 or 2.0 mg/kg/day. No with an uncertainty factor of 100 due to are available on levels of effects were reported for routine ehort-term human data (2 months) and monochlorobenzene in foods to biochemical and hietological 20 pircent contribution from drinking determine a daily dietary intake. examination of the organs. Ueing 2.0 water. The NAS (Drinking Water and Ambient air monitoring data are mg/kg/day as a NOAEL, an uncertainly Health. 1977. Vol. I) has calculated an available from over 800 site locations in factor of 10 and consumption of 1 liter AD1 for methoxychlor of 0.1 mglkglday 16 States. From median values of these (child) or 2 litere of water (sdult) per baaed on a &year etudy (fiodge. et el.. data, the estimated rural/remote. urban/ day, 13-day asseeements of 2.0 mg/l for 1952. Chronic Oral Toxicity Tests of suburban and sourze dominated levels a 10 kg child and 7.0 mg/l for a 70 kg Methoxychlor in Rats and Dogs. J. of monochlorobenzene in ambient air adult were calculated. Pharmacol. Exp. Ther. 104:80) in rets, approximate 0.0,1500 and 140 ng/m? An AADl was calculated for using a NOAEL of 10 mg/kg/day and an respectively. Therefore, respiratory methoxych!or baaed upon a feedin uncertainty factor of 100. The AADl is intake for the adult male is expected to study in rats where male and femaf e baaed upon a lower identified NOAEL in vary from 0 to 32 pg/kg/day. rate (FDA (unpublished], 1951; Lehman. a newer study compared with the NAS' Respiratory intake for formula-fed l€R35), fed diets containing 10,25.100, ADI. infants could vary between 0 and 22 pg/ 500 or 2ooo mg/kg/diet methoxychlor for The WHO has eetablished an AD1 for kg/day. 2 years. Growth retardation occurred at humans of 0 to 0.1 mg methoxyc'rlor/kg Drinking water monitoring data the highest dosage level in males, and at bw (Joint Meeting of the FA0 Working indicated that 99.9 percent of the public dosage levele of 200 mg/kg/diet and Party of Experts on Pesticide Reeidues drinking water systems contain either above for females. Using 5 mglkglday and the WHO Expert Committee on no monochlorobenzene or levels less (100 mg/kg/diet) as the NOAEL. an Pesticide Residues, 1975). The basis of than 0.5 pg/k 0.1 percent are estimated uncertainty factor of 100 based upon an the AD1 was not identified. The WHO to have levels of monochlorobenzene in animal study and consumption of 2 litera has also recommended a guideline value drinking water ranging from 0.5 to 5 pg/ of water per day, an AADl of 1.7 mg/l (1984) of 30 pg/l for methoxychlor based I. All exposure to monochlorobenzene in was calculated. upon drinking water as one percent of drinking water at levels above 0.5 pg/l The evidence from atudiee with the ADI. is projected to come from ground water experimental animals and in vitro A detection odor threshold value of sources. Monochlorobenzene has bcen assaye indicate8 that methoxychlor is 4.7 mg/l in water for methoxhchlor is detected in drinking water in three not a carcinogen, mulagen or teratogen reported in the Ilterature. States.

F4701 rev. 6-14-65 - Federal Register / Vol. 60, No. 219 / Wednesday, November 13, 1885 / Proposed Rule8 47001

Monochlorobenzene has been hepatic necrosis, nephrosie and chronic toxicity data hecouse the identified at five hazardous waste sites lymphoid necrosis. A NOAEL of 125 m8/ bloassy data (NTP study) are designated in complaints and consent kg/day was identified from this study. preliminary and an lnadcquate basis for decrees under the Comprehensive Using this NOAEL, an uncertainty factor extrapolation. An additions1 fsclor of 10 Emergency Response Compensation and of 100 based upon an anlmal study with was applied because an order of Liability Act of 1980 (CERCLA) and the the NOAEL identifled, and uncertainty magnitude uncertainty factor was Nalional Contingency Plan (40 CFR Part factor of 10 to conver! from subchronic determined to be sufficiently protective 300). The concentration of to chronic exposure and consumption of for this chemical. monochlorobenzene was not given for 2 liters of water er day, a provisional An RMCL and primary regulation will four sites: however, ground water AADl of 3.0 mg/ P was determined. be proposed for monochiorobcnzcne migration was mentioned as a problem Using the same NOAEL of 125 mg/kg/ because of the potcntisl adverse effects a1 two sites, one of which had a day and an uncertainly factor of 100 and occurrence in drinking water. concentration in ground water of 100 based upon an animal study identify a Monochlorobenzene has been classified mg/l. NOAEL and adjusting for ex usure, a an a possible carcinogen and the Health Effects. Acute, high dose 10-day assessmenf of 30 mglfor a 70 kg proposed RMCL of 0.08 mgll for effects of monochlorobenzene include adult and 9 mg/l for a 10 k child can be monochlorobenzene is based on a sedation, anesthesie and death due to derived. These levels are af so protective provisionel AADl of 3.0 mg/l for non- respiratory failure. Chronic exposure to for %day exposures in the adult and carcinogenic effects and an additionul these compounds ma result in blood child, factor of 10, assumintq 20 percent dyscrasias and lung, river and kidney Monochlorobenzene has been shown contribution from drinking wutcr. damege. The prlncipal target organ9 of to cause mutagenic effects In hlgher Questions for Comment: monochlorobenzene are the cenlral plants and certain microorganisms. 1. Should monochlorobenzene btr nervous system, liver and kidney. Monochlorobenzene was tested for its classified In Group No adequate dose-respones data are carcinogenic polentiel in rata and mice EPA's C? available from which to derive a 1-day 2. What should be the busis for tho In the NTP bloassey progrom (NTP, RMCL for this compound? assessment for either the 10 kg child or 1983. Draft NTP Technical Report of the the 70 kg adult. It is recommended that, Carcinogenicity Bioassay of 3. The 10-day assessments, based for this duration of exposure. the 10-day Chlorobenzene (CAS #108-80-7) in upon a study done in rabbits, are lower assessment be applied. F3441N Rats and BsCaFl Mice). The than the Longer-term assessments or the The 10-day assessment was derived results of the study showed that AADl which were derived from studies from inhalation data in the teratology monochlorobenzene-adrnlnistration performed with rats and mice. It is study in rats and rabbits (Hayes, et el,, increased the occurrence of neoplastic apparent that these species exhibit 1882. Monochlorobenzene inhalation nodules of the liver in the high dose (120 differing sensitivities to the chemical. teratology study in rats and rabbits. mglkg) male rats. Carcinogenic effects That the rabbit were used for the 10-day Unpublished report. Toxicology were not observed in female rats or assessment is in keeping with the Research Laboratory. Dow Chemical mice of either sex. On the basis of these philosophy of using information from the Company. 115 pp.). Animals were preliminary data, the NAS (Drinking most sensitive species tesled. However, exposed trt 0.75,210 or 590 ppm, 6 hr/ Water and Health, 1983. Vol. V] derived data on the rabbit were not available for day on days 6-15 (rat) or days 6-18 an eatimate of risk of daily exposure to longer durations of exposure. 1s it (rabbit) or pregnancy. No toxicity, fetal monochlorobenzcne in drinking water. appropriate to use the rabbit data for the or maternal, was observed in the rats at This risk estimate is shown in Table 13. 10-day assessment or should data from any dose. In the rabbit dams, increased EPAs ambient water quality criteria the comparablb study in the rat have relative and absolute liver weights were (U.S. EPA. 1980. Ambient Water Quality been used? Should the Longer-term observed at the two higher doses. Using Criteria for Chlorinated Benzenes &lo/& assessment and/or the AADl be the NOAEL of 75 ppm (18 mglkglday). a 60428) for monochlorobenzene are 488 modified to accommodate for the lack of 10-day assessment for the 10 kg child of pg/I based upon toxicity data and 20 data in the more sensitive species and, 1.8 mg/l was derived. A comparable g/l based upon organoleptic data. The thus, perhaps, an inadequate margin of assessment lor the 70 kg adult would be kvel based upon toxicity data (488 pg/l) safety when attempting to identify a 6.3 mg/l. was calculated based upon a NOAEL level of exposure .:or the human that The study selected for the derivatlon from animals of 14.4 mglkglday and an would be protective? of the provisional AADI was a uncertainty factor of 1ooO. The 18. Polychlorinated Biphenyls subchronic study in which rats and mice provisional AADI was based upon were administered monochlorobenzene newer data than as used to derive the Polychlorinated biphenyls (PCBs) are five times weekly by gavage in corn oil water quality criteria level. the WHO a class of colorless and stable at doses of 0,80,125,250,500 or 750 mg/ drinking water quality quideline for chemicals. They contain a biphenyl kg [Baltelle-Columbus, 1878~. monochlorobenzene (1984) is 0.3 pgll, nucleus with twa or more substituent Chlorobenzene. Subchronic Toxicity based upon o anoleptic considerations. chlorine atoms. Technical PCBs are Study Be6Fc Mice. Unpublished report; Monochloro enzene has been mixed isomers from 10 classes of Battelle-Columbus, 1978d. classified in EPA'sT Group C, according chlorobiphenyls containing 209 possible , Chlorobenzene. Subchronic Toxicity to EPA's Proposed Guidelines for Isomers. In general, PCBs are insoluble Study-Flscher 344 Rats, Unpublished Carcinogen Risk Assessment, based In water and are soluble in many report). This study showed significantly upon the preliminary data from the NTP common organic solvents. increased liver/body weight ratios in study. Monochlorobenzene has been Prior to 1971, mixtures containing up mice of both sexes at 500 and 750 mg/kg, placed in Regulatory Category I1 and the to 88 percent chlorine were used in a and a slight increase in males at 125 mg/ RMCL has been eel based u on the number of applitxtions, including kg. Both mole and female rats showed provisional AADI of 3.0 mgb with an plasticizers, heat transfer fluids. an increase in Iiver/body weight ratios additional factor of 10, with 20 percent . hydraulic fluids, compressor lubricants, at 250 and WO mg/kg. Mice and rats at drinking water contribution factored in. wax extenders, waterproofing aids (in the three highest doses all exhibited The RMCL Is proposed based upon surface coatings), printing inks,

Sa4999 OlOl(M)(l2-NOV-8S-15:27:30) F4701 rev. 6-14-85 47002 Federal Reglster / Vol. 60, No. 218 / Wedneeday, November 13, 1985 / Proposed Rule8 carbonless copy paper, as well as in the presence of a microsomal Pentachlorophenol is also used in ingredients in lacquers, paints, activation system. The results showed 4- termite prevention on farms. The only varnishes and special adhesives. In chlorobiphenyl to be significantly , currently registered agricultural uses are 1974, PCBs were a major component of mutagenic in this aaeay. A National seed treatment or seed crop uses. capacitore and of transformers and Cancer Institute study (NCI, 1978. NCI Pentachlorophenol is slightly soluble in millions of pounds were manufactured. Carcinogeneels Technical Report Series water (18 mg/l at 25 'C). After 1978, the manufacture of PCBs was No. 36) examined the effects of PCBs Pentachlorophenol has been used In discontinued in the US. ingested through the diet for 2 years. wood products that come in contact Analytical Methods The results showed a high incidence of with drinking water. hepatocellular proliferative lesions as In July 1984, the Agency issues a Analytical methods availoble for well as adenofibrosis; however, the notice of intent to cancel registratlone analyzing PCBa in drinking water incidence of hepatocellular adenomas for pesticides containin include the solvent extraction gas and carcinomas was not found to be pentachlorophenol andyor its salts chromatography technlque. eignificant. In another study unless labeling was amended. EPA Humon Ex osum. The FDA estimated (Klmbrough, et el, 1975. journal NCI. restricted wood -reservetive use to the total add intake of PCBs to be 0.93 551453), feeding of PCBs at a certlfied applicators; added protective pg/day. The major sources are dairy concentration of 100 mg/kg for 21 measures to reduce exposure; prohibited products (0.37 p /day); meat, ?ah, and months resulted in neoplaetlc nodules application in homes and to most wood poultry (0.62 pgfday); and fats and oils and hepatocellular carcinomas. The intended for indoor use or In contact (0.03 pglday). Trends in daily intake for IARC classified PCBs In Croup 2B; with food, feed, or water; prohibited use the years 1977,1978, and 1979 are 0.018, inadequate evidence for carcinogenlclty of pentachlorophenol treated logs for 0.027 and 0.014 pg/kg body weight, in hwnans, sufficient evidence for construction of log homes; and required respectively. carcinogedcity in animals and a limit on the hexadioxin contaminant. No information was available on inadequate evidence for activity in human intake of from ambient air. This Agency action has been challenged PCBs short-term tests. PCBs have been and administrative proceedings are National data on the level of PCBs in classified in EPAs Group B2, according drinking water comes from the National underway. EPA has also issued a data to EPA's Proposed Guidelines for call-in for non-chronic data such as Organics Monitoring Survey (NOMS] Carcinogen Risk Assesment, based upon conducted in 1978-77. PCBs were found mutagenicity, metabolism and air the positive results in studies in mice monitoring studies. In late 1984, the in e percent of finished ground water and'rats. supplies at levels of 0.1 pg/l. were Agency alee initiated actions to cancel PCBs WASCAG and the NAS have derived virtually all registratlone of detected in approximately 2 percent of estimates of risk of daily exposure to finiohed surface water systems; pentachlorophenol for non-wood PCBe based upon .I long-term study preservative uses. quantified levels were lese then or equal (Kimbrough, et al. 1975 Journal NCI. to 1.4 pg/l. In a report published in 1978, Analytical Methods. Analytical 551453), in which rats were fed PCBs methods available for analyzing one State indicated that PCBa were (Arochlor 1.W) at a dose of 100 mglkg observed in 32 out of le3 grounE water pentachlorophenol In drinking water body welght. The CAG and NAS risk include the eolvent extraction-gas supplies sampled; concentrations as estimatee are shown in Table 13. high as 1.27 pg/1 were detected. The available data suggests that PCBe chromatography technique. PCBs have been identified at ten (Arochlor 1260) have carcinogenic Human Exposure. Although not hazardous waste sites designated in effects in animals. For this reason and detected in adult dlet studiee, complaints and consent decrees under because of the occurrence and potential pentachlorophenol was detected in 10 the Comprehensive Emergency occurrence of PCBs in drinking water, percent of oils and fat samples in the Response Compensation and Liability an RMCL and a primary regulation will FDA infant dlet study in 1979 at a Act of lee0 (CERCLA) and the National be proposed. An RMCL of zero is concentration of 18 pg/kg. Additional Contingency Plan (40 CFR Part 300). The proposed for PCBs as a class of data were obtained on the estimated concentration of PCBs ranged from no compounds, based upon the total intake of pentachlorophenol for level given for three sites; 4-20 pg/l in carcinogenic effects noted for Arochlor adults in 1974-1979 and for infants In runoff. 11.7-200 pg/l in sedlments, 127- 1280. 1976-1979. The average total intakes for 444,OOO pg/l in soil, zoOpg/I in creek Questions for Comment: adults, infante and toddlere over the water, 7-175 pg/l in leachate, 80-215 1. Is there adequate evidence to base years studied were 0.010,0.005 and 0.009 pounds in an underground oil-water the RMCL for all PCBs upon pglkglday, respectively. The FDA layer, to 28 g/l in ond effluent. carclnogenlc effecta? toddler diet study of 376 detected Heolth Ejects. SRort and longer term 2. PCBs include several chlorinated pentachlorophenol in 10 percent of the exposure to PCBs in animals 11. a variety biphenyls and unknown contaminants. oil8 and fate samples at a concentration of physiological and morphological Variabillty in the health effects of Of 24 P8;b a:terations to the liver including liver eeveral PCB iaomere have also been Pentacliloroph.,,iol ha8 been detected enhrgement, fatty infiltration, reported. I8 eettlng regulations for PCBs in rive- Rnd streams (0.0146 pg/l) and centrilobular necrosis and effecte on as a class of compounds appropriate? limited data show it may occur in liver prophyrin metabolism. The major What alternative trpproach would be drinking water from surface supplies. biochemical effects of PCBs are the better? Pentachlorophenol was detected in the inductive effect on hepatic mixed- NSP in two surface water systems (1.3 function oxidase enzymes and 19. Pentechlorophonol and 12 @). None of the 12 ground modification of prophyrin metabolism. Pentachlorophenol (FCE or pents) has water systeme examined for Short-term assessments or a provlsional been used as a herbicide, defollant, pentachlorophenol in the NSP contained AADI have not been determined for insecticide, fungicide and wood levels in excess of the quantification PCBS. preservative. Eighty percent of the limit of 1.0 pg/L PCBs have been studied for mutagenic pentachlorophenol produced is ueed In Pentachlorophenol hae been identifled effects using Sulmonellu fyphimurimum, the treatment of wood. at one hazardous waste site designated

S-074999 0102(06~12-NOV-85-IS:27:32) F4701 rev. 814-85 Federal Regieter / Vol. 219 / Wednesday, November 13, / Proposed Rules 47003 60, No. it485 - In complaints and consent decrees fed dases of 0,1,3,10 or 30 mg in humans, inadequate evidence for under the Comprehensive Emergency commercial pentachlorophenol/kg bw/ carclnogeniclty in animals and Response Compensation and Liabllity day (Schwetz, B.A., J.P. Quast, P.A. inadequate evidence for activity In Act of 1980 (CERCLA) and the National Keeler, LG Humiston and R.J. Kociba, short-term teats. Pentachlorophenol has Contingency Plan (40 CFR Part 300). The 1978. Results of 2-Year Toxicity and been classified in EPA's Group D. concentration of pentach!orophenol was Reproduction Studles on according to EPAs Proposed Guidelines not given. Pentachlorophenol in Rats. In: K.R. Reo, for Carclnogen Rlsk Assessment, based Health Eflacts. Pentachlorophenol is ed. Pentachlorophenol: Chemistry, upon inadequate data in animal studies. rapidly absorbed following oral Pharmacology and Environmental The EPA ambient water quality exposure, with the major sites of tissue Toxicology. Plenum Press. N.Y. pp. 301- criterion for Pentctchlorophenol (US. deposition heing the livers, kidneys, 309). At the highest dose level, increased EPA. 1980. Ambirnl Water Quality brdln, spleen and fat. It is rapidly serum glutamic pyruvic transaminase Crlteria for pentachlorophenol. EPA excreted following a single dose, while activity and pigmentation of tho liver 440/5-eo-oe5) is either 1.01 mg/i bdsed during chronic exposure the biological and kidney were observed in both males on toxicity data or 0.03 mg/l based on half-life appears to be approximately u) and females. At a dose of 10 mg/kg bw/ the organoleptic properties ol ,\aye. The major route of excretion is via day, pigmentation of the liver and pentachlorophenol. The 1.01 mg/l value the urine. kidney was observed in the females, but is based on the same study used for the The malor targets of not in the males. An AADI of 1.1 mg/l AADI calculation and also considers pentachlorophenol toxicity are the her, was calculated from a NOAEL of 3 mg/ bloconcentration by fish. In an EPA kidneys and central nervous system. kglday, with an uncertainty factor of Position Document 4 on Wood Pentachlorophenol produces 100 baaed upon an animal study and Preservative Pesticldes, the Agency pigmentation, increases liver weight and conaumptlon of 2 liters of water per day. regulatory posltion to restrict ueage of induces hepatic enzymes in the liver. Commerclal grades of pentachlorophenol considered. with The malor renal effects have been pentachlorophenol used in toxicity respect to health risk, teratogenicity and reported to be increased kidney weight studies with animals commonly contain fetotoxicity of pentachlorophenol and and pigmentation, while effects on the the following nonphenolic contaminants: oncogenicity of its hexachiorodibenzo-p- central nervous system include capillary hexachloro-p-dioxin, heptachloro-p- dioxin (HxCDD) and hexachlorobenzene congestion and chromatolysis of the dioxin, octachloro-p-dioxin, contaminants. nerve cells. Pentachlorophenol is hexachlorodibenzofuran, Odor thresholds of 857 pg/l at 30 'C fetotoxic and has adverse effects on heptachlorodibenzofuran, and reproduct Ion. and 1600 pg/l at 20-22 'C and a taste octachlorodibenzofuran. These threshold of 30 pg/l have been reported One-day assessment were calculated contaminants affect the toxicity of the baaed on a study in rats (Nishimura, et in the literature for pentachlorophenol. pentachlorophenol being studied and The WHO guideline for el. 1982. Effects of Pentachlorophenol on would result in toxic effects being noted pentachlorophenol (1984) is 10 pg/L This the Levels of Hepatic Glycogen. Sangyo which could not be attributed to Isaku. 24(4):398399) where a single oral pentachlorophenol. 2,3,7,& value is based upon an AD1 of 3 pg/kg body weight with 10 percent of the AD1 dose of pentachlorophenol was shown Tetrachlorodibenzo-p-dioxinwas not to increase liver wei hts. Using a detected In commercial attributable to drinking water. The AD1 NOAEL of 10 mglkgfday. an uncertainty pentachlorophenol used in the toxicity was based upon an uncertainty factor of factor of 100 and consumption of 1 liter tests described above. io00 applied to unspecified animal date. (child) or 2 litere (adult) of water per The NAS (Drinking Water and Although commercial day, a 1-day assessments of 1.0 mg/l for Health, 1077. Vol. I) has calculated an pentachlorophenol contains residues of a 10 kg child and 3.5 mg/l for a 70 kg AD1 of 0.021 mg/l based on a mday hexa- and octachlorodioxin, the RMCL adult were calculated. feeding study in rats (Johfison, R.L.. P.1. is based upon the parent Ten-day assessments were calculated Gehring, R.J. Kociba and B.A. Schwetz, pentachlorophenol. This is because data bared on a NOAEL of 3 mg/kg/day for 1073. Chlorinated Dibenzodioxins and indicates that the mobility of the dioxin liver pathology in rate in a -day Pentachlorophenol, Environ. Health contaminants is often less than the feeding study with pentachlorophenol Persper. Exp. Issue No. 5, Sept. 1973, pp. mobility of the parent compound and (Johnson, et el. 1973. Chlorinated 171-175). This value was determlned thus the parent compound would be the Dibenzodioxins and Pentachlorophenol. before the results of the 24-month rate chemical of concern in drinking water. Environ. Health Perspec. Exp. 6:171-175) study which is more appropriate for an The potential exposure to the dibxin and for reproductive effects in a one- AADI calculation, due to the length of contaminant will be dealt with eneration reproduction study in rats the study. separately (see section on 2.3,7- 'Ied pentachlorophenol in the dlet Pentachlorophenol has not been tetrachlorodibenzo-p-dioxin). (Schwetz, et el. 1978. Results of 2-year shown to be mutagenic in Salmonella Exposure to pentachlorophenol at Toxicity and Reproduction Studies on typhimurium. Escherichia coli or sufficient levels results in effects on the Pentachlorophenol in Rats. In: T.R Reo, Sermtia mamescens. Two oral liver and kidney. Since ed. Pentachlorophenol: Chemistry, carcinogenicity studies have been pentachlorophenol has been detected in Pharmacology and Environmental camed out on penthchlorophenol. There drinking water and Is likely to be . Toxicology, Plenum Press, NY pp. 301- were no significant differences In tumor occurring in drinking water, an RMCL 309). Using an uncertainty factor of 100 response between treated and control and primary regulation will be proposed. and consumption of 1 liter (child) or 2 animals in either of these studies. The An RMCL of 0.2 mg/l is proposed based litere (adult) of water per day, 10-day National Toxicology Program is upon an AADI of 1 mg/l and an assessments of 0.3 mg/l for a 10 kg child currently testing pentachlorophenol for assumed drinking water contribution of and 1.1 mg/l for a 70 adult were carcinogenic activity. No data from 20 percent. calculated. these studies are currently avallclble. Questions for Comment: An AADl was calculated for The IARC has classified 1. Are eddltional data available on pentachlorophenol based upon a 24 pentachlorophenol in Group 3; exposure through food, air and other month feeding study in which rats were inadequate evidence for carcinogenicity sources for pentachlorophenol?

F4701 rev. 6-14-85 47004 Federal Register / Vol. M), No. 218 / Wednesday, November 13, 1085 / Proposed Rules

2. Is there adequate toxicolo ical alterations in hepatic nnzyme activity Toxicological Studies of Certain evidence that the presence of Belected and blochemlcal changes in the brain. Alkylated Benzenet and Benzene. Arch. non-phenolic contaminants in One-day assessments are based upon Ind. Health. 14387-3t;ql. Ueing a NOAEL commercial pentachlorophcnol would a study (Srivastava, et al. 1882. Hepatlc of 0.133 mg/kg/day, with an uncsrtainty affect the AADI? Effects of Orally Adminietered styrene factor of 1OOO and the assuniption that 20. Styrene in Rats. 1. Appl. Toxicol. 2(4)219-2221 in 20 percent of total intake is via drinking whlch the NOAEL for increased water, a value of 0.8 mg/l was Styrene (vinyl benzene or ethenyl eenait'vity of dopamine receptom in the determincd. benzene: CAS # 1oo-S2-5) is slightly brain wan determined to be 270 mg/kg/ Styrene has been tested for soluble in water (0.32 mg/l) and soluble day. An uncortalnty factor of 100 was carcinogenicity in several animal in many organic solvents. In 1982, the applied and the consumptlon of drinking studies. In one study [Ponomarkov. V.F. total U.S. production of styrene equaled water was based upon 2 litere/day for and Tomatis, L, 1980. Effects of Long 5,042,037 pounds. Styrene le used the adult and 1 Iiterlday for the 10 kg Term Oral Adminietration of Styrene lo exteneively for the manufacture of child. The one-day number is 84.5 ma/! Mice and Rats. Scanrl. J. Work Environ. plastics, Including polystyrene, rubber for the adult and 27 mg/l for the 10 kg Health. 4 (Suppl. 2)127-135). an modifled impact polystyrene, child. increased Incidence of lung tumors was acrylonitrile-butadiene-styrene (ABS), Ten-day assesements are based upon found in one strain of mlce, but thin dose and styrene-acrylonitrlle copolymer minor hepatotoxicity in rats (Agrawal, resulted in exceesive early mortality. (SAN). It is also us;d :n the manufacture et el. 1982. Effects of Styrene on Elevated tumor incidancas were not of synthetic rubber, resina, and Dopamine Receptors. Bull. Envlron. observed in another lrtrain of mice nr ineulatora. Some resins manufactured Contam. Toxicol. 29(4):400403). A rats. In the National Cancer Institute from styrene are used in the treatment NOAEL of 200 mg/kg day was bioaseay of styrene, a statistically of potable water. determlned, with an uncertainty factor significant increase in alveolar/ Anal tical Method. Analytical of 100 and consumptl,rr of 1 liter (child) bronchiolar adenomas and carcinomas methody s available for analyzing styrene or 2 illere (adult) of water per day, Ten- was seen in male and femaie rats at a in drinking water include the purge and day numbers of 70 mg/l for the adult trap-gee chromatography technique. dose of 300 mg/kg/day (NTP,NCI No. and 20 mg/l for the 10 kg child were 1885,1879). In en inhalation study Human Exposure. No information is determined. available on the occurrence of styrene in (Jersey, G.M., et el. 1878. Two year A provisional AADI was calculated Chronic Inhalation Toxicity and food. Low level contamination of some from u etudy where beagle dogs were foods la expected became polymers and Carcinogenicity Study on Monomeric given styrene in a peanut oil suepenaion Styrene in Rats. Dow Chemical Study renins of styrene used in packaging by gavage 7 days/wk for 580 days commonly contain a detectable level of for MCA. Dec. 6,1978), the incidence of (Quest, JJ.,R.P. Kalnins, KJ. Olson, et leukemia/lymphoearcomas was slightly the monomer. el., 1978. Results of a toxicity ntudy in Data on exposure lo styrene through dogs and teratogeiilcity studlee in elevated in female rats. The IARC has inhalation of ambient air are limited. rabbits and rate administered claesified styrene In Group 3: Styrene has been detected in ambient inadequate evidence for carcinogenlcity monomeric styrene. Tox. Appl. Pharm. in humans, limited evidence for air in source dominated areas at 45:293-294). Dose level8 were 200,400 or approximately 2.3 pg/m? This level carcinogenicity in animals and sufficient 800 mg/kg bw/day. The controls evidence for activity in short-term teats. could lead to a reepiratory intake for received peanut oil only. At the two adults of approximately 52 pglday. higher dose levels, minimal Styrene hae been cltlssified in EPA's Nearly lo00 drinking water eamples histopathogolic effects were noted in the Group C, according to EPA'e Proposed from ground water and 100 surface liver (increaeed iron deposits within the Guidelinee for Carcinogen Riek water supplles have been tested in reticuloendothelial cells) as well as Aseessment based upon several posltive national monitoring surveys to hematologic effects that included animal studies which are limited due to determine the presence or absence of increaeed Helm bodies in erythrocytes poor survival of the animals. Styrene styrene. Styrene was not detected in any and a decreased packed cell volume. At hae been placed in Regulatory Category of these samples. the lowest done level (200 mg/kg/day), I1 and the RMCL is proposed baeed upon Styrene has been identified at one these effects were not noted. Using uw) the provisional AADI of 7.0 mg/l with an hazardous waste site denignated in mg/kg/day as a NOAEL in both speciee additional factor of 10, with 20 percent complaints and consent decrees under and an uncertainty factor of loo0 bwed drlnking water contribution factored in. the Comprehensive Emergency on an animal etudy of less than lifetime The RMCL Is baeed upon chronic Response Compensation and Llability exposure and consumption of 2 litem of toxicity data because die bioassay data Act of 1980 (CERCLA) and the National water per day, a provisional AADI of 7 are very limited and inadequate for Contingency Plan (Sr C,FR Part 300). The mg/l was determined. extrapoletlon purposes. An additional concentration of styrene wan pot hen. Styrene has not been ehown to be factor of 10 was consewatively applied HeolfhEffects. Styrene le read& mutagenic In Salmonella typhimurium in based upon the equivocal evidence of absorbed from the gastrointestinal tract the absence of metabolic activation, carcinogenicity. and distributed throughout the body, while positive results have been The odor threshold for styrene is accumulating in adipose tiseue. Styrene obtalned in yeast, fruit flies and cultured between 10 and 60 ppm while the taeto is metabolized to styrene oxide, a highly mammalian cells with metabolic threshold le between 0,005 and 0.773 reactive intermediiie. The acute toxicity actlvation. Styrene produced positive W/l. of styrene is relatively Inw, with reaults in cultured mammalian cells, Exposure to styrene at high done reduced weigh1 gain, increased kidney ieolated human lymphocyte8 and when level8 results in adverse health effects in and llver weights and lung congestion tepted in vivo in rate and mice. animals. Because styrene is likely to be exhibited following non-lethal The NAS (Drinking Water and occurring in drinking water, €PA will I exposures. Repeated inhalation Heolth, 1977. Vol. 1) has calculated an propose an RMCL and primary exposures at very high dose levels in AD1 of 0.133 mg/kg/day baeed upon a regulation. An RMCL Of 0.14 rq/l is animale have been rvporled to reeult In study In rats (Wolf, MA., et el, 1856. proposed, based upon an AADI of 7 mg/

sM4999 OIW(M~12-NOV-BJ-IJ:27:36) FA701 rev. 8-14-35 Federal Reglnler / Vol. SO, No. 219 / Wednesday, November 13, 1985 / Proposed Rules 47006 - 1 with an additional factor of 10 and 20 based upon a 100 ppm (377 mg/m? Toluene has not been shown to be percent drinking water contribution. NOAEL identified in humans following mutagenic in the Ames Salmonella Question for Comment: single inhalatlon exposures of up to 8 fyphiniurium assay, with or without rut 1. Should styrene be classified in hours (von Oettlngen, et el. 1842a. The her Se homogenate, an#Jhes been EPA'r Group C? What should be the Toxicity and Potential Dangers of shown to be ineffective in IncreasinR the basis for the Kh4CL for this compound? Toluene, wlth Speclal Reference to its reversion of an E. coli strain lo 21. Toluene Maximal Permissible Concentration. tryptophan-independence. U.S. Public Health Servlce Pub. Hllh. Limlted dab are evalitlble on the Toluene (methyl benzene: CAS #IO& Bull. No. 270.50 pp: von Oettlngen, et el. carcinogonic effects of tolupne. Only one 88-3)is an aromatic solvent. It is slightly 1842b. The Toxicity and Potential long-term bloausHy of toluene hus been soluble in water (53dmg/l) and IS Dangers of Toluene-Preliminary report. conducted: this study (C.1.i.T.. 1880. soluble in alcohol, benzene, ether, 1.A.M.A. 116679684; Carpenter, et el. Unpublished) concluded thHt toluene is acetone, and other organic solvents. 1844. Studies on the inhalation of 13 not carcinogenic following Inhalation in Much of the toluene produced is blended Butadiene: with a Comparison of its directly into aviation gaeollne. Toluene rats. The Natlond Toxicology ProHram Narcotic Effect with Benzol, Toluol and Is conducting 2-year carcinogenicity also is used as a starting material in the Styrene, with a Note on the Elimination bioassays on toluene in whlch the production of benzene and other of Styrene by the Human. 1. Ind. Hyg. compound is being adminlslercd by chemlcals, and is used as a solvent for Toxlcol. 2889-78; Ogata, et el. 1970. paints, coatings, gums, oils, and realns. inholotion and gavage to rats end mice. Analytical Method. Analytical Urinary Excretion of Hlppuric Acid and Toluene has been classiflsd In EPA's methods available for analyzing toluene m- or p-Methylhippuric acid in the Urlne Group D, according to EPA's Proposed of Persons Exposed to Vapors of Guidellnes for Carclnoaen Risk in drlnkin water include the purge and Toluene and or p-Xylono as a Test of trap-gas ca romalogrnphy technique. m- Assesem~nl,based upon neg:itlvn Humar, Exposure. No information wan Exposure. Brit. J. Inti. Med. 27(1): 43-40:. reRulls in an ii,halation study end available on the intake of toluene from A total absorbed dose of 18 mg/kg was inadequate data through ingestion food. determined, assuming a hunian exposure. Data compiled for EPA's Office of Air respiratory inhalation volume of 20 ins/ EPA's amblent water quality criterion Quality Planning and Standards Indicate day and an absorption efficiency of !io (US. BPA. 1800. Aniblcnt Water Quality that the mean ambient air levels of percent for a 70 kg adult. From this total Crlteria for Toluene. 440/5-wM75) for toluene are 0.3 pg/msfor rural/remote absorbed dose, a 1-day number of 18 toluene is 14.3 mg/l baaed upon a 6 areas, 2.8 g/m' for urban/suburban mg/l was derived for the 10 kg chlld, month oral study In rats [Wolf, et el. areas, ant 23 pg/ms for source assuming consuaptlon of 1 llter of water 1956. Toxlcologlcal studies of Cerlaln dominated areas. Using the value of 3.8 per day. A 1-day number of 63 mg/l was Alkylated Benzenes and Benzenc. Arch. pg/m*, the mean respiretory Intake of derived for the 70 kg adult, assuming Ind. Health. 14387). The study used to toluene for adults is calculated to be 83 consumption of 2 liters of wale: per day, derive the AADI is a liretime study and Pg/daY* applying an uncertainty factor of 10, was thus determined to bo more In the CWSS, toluene wad measured appropriate for use wlth adequate appropriate for the derivation of the in two ground water systems, at human data. AADI than the &month study descrihed concentratlone of 0.505 and 0.58 pg/L Because of the lack of appropribte above. Three surface water supplies had exposure duration data, the 10-day The odor tlireshold for !oluene in measurable concentrations of toluene- assessments were derived from the 1- drinking water is 1 mg/l. 0.52,0.72 and 1.62 pg/L Toluene was day assessments by dividing each 1-day Exposure to toluene at high dose detected in six randomly selected number by 3 to give estimated 10-day levels results in central nervous system systems tested during the GWSS. Levels values. The use of a %fold uncertainty depression and other systemic effects; it ranged from 0.5-2.8 pg/l. factor, rather than the more usual 10- has occurred in many drinking water In the NSP, approximately 20 percent fold factor, is substantluted by the supplies. Thus, a primary regulation will of the surface water supplies sampled nature of the kinetic and toxic properties bc proposed. The RMCL is proposed at contained detectable levels of toluene in of the compound, Le., rapid uptake and 2.0 mg/l based upon an AAIH of 10.1 finished water. Measured excretion and little blo-accumulation mg/l for non-carcinogenic efft?cta concentratlone ranged from 0.1 to 1.4 potential. The resulting 1Gday number assuming 20 percent contribution from pg/l, with a meen of 0.295 pg/L A level for the 10 kg child is e mg/l and for the drinking water. of 0.1 pg/I was measured in the one 70 kg adult, 21 mg/l. ground water system in which toluene An AADI has been determined for 22. Toxaphene was detected. toluene based upon a laboratory study Toxaphene (a mixture of Clo State agencies have also detected in which rate were exposed to toluene chlorinated camphenes with an toluene in drinking water. Levels as high via inhalation at 0,113,337 or 1130 mg/ approximate overall empirical formula as 2,500 g/1 have been reported. mafor 6 hours/day, 5 dayelweek for up of CIOHIOCL:current MCL is 5 pg/l) is a Healt/Effecls. Acute exposure to high to 2 years (C.I.LT., 1980 iinpublished. A persistent, broad spectrum insecticide. levels of toluene in animals results in Twenty-four Month lnlvdatlon This product was used extensively on central nervous system depression and TOX~CO~OR~Study In Flsher-344 Rats food and fiber crops for rnony yenrs, blir effects on the lungs, liver and kidney. Exposed to Atmospherlc Toluene). No current registered I~WSarc limitad. Toxic effects followlng chronic exposure dose-related adverse effectn were The solubility of toxaphene In water are simllar to those seen following acute identified from this study and a NOAEL is approximately 0.4 rng/l. The EPA exposure, predominantly on the kidiieys of 1130 mg/ms was identlfled. Using this Toxaphene Work Group reported that NOAEL, an uncartainty factor of 100 toxaphene le highly persistent and based upon an animal study and accumulates in the environment. aasumlng M) percent piilmonary . Anal tical Methods. Analytical exist from which to derive 1-day abrorptlon, an AADI of 10.1 mg/l wan metho& available for analyzing aaseasrnenls, Thus, thelr dedvatlon waa delermined, toxaphene in drlnkinq water include the

s-074999 OlOS(M)( 12-NOV-85- IS:27:3B) F4701 rev, 8-14-86 - El'

47008 Fadecal Regleter / Vol. 60, No. 218 / Wednesday, November 13, 1885 / Proposed Rulee - solvent exlraclicn-gas chromatography Occasional convulsions were also noted of contaminated water and aquatic technique. at this level. Using the LOML of 4 mg/ organisms is su ested as concentration Human hkpa~um.In FDA's kglday, the ten-day health advisory is levels of 7.1 ngfffl0.71ng/l and 0.071 ng/l comp1ianh.e program report for FY 77 on 0.08 mg/l for a 10 kg chlld and 0.28 mg/l equlvalent lo calculated excess cancer pnstkides and metals, toxaphene was for a 70 kg adult, using an uncertainty risks of 10'9 lo-? and lo-? respectively. dc!ected in 3.3 percent of samples factor or 500 end u)oo,respectively. Toxaphene has been reported to have tested. In the FY 79 total dietary study, The NAS (Drinkin Water and an organoleptic threshold of 0.14 mg/l the FDA detected toxaphene levels Health, 1977. Vol. I) I! as calculated an and the WHO has not determined a ranging from 10 to 68 pg/kg in 10 percent AD1 of 0.00123 mg/kg/day for guideline for toxaphene In drinking of the garden fruits included in the toxaphene. This was based upon a 2- water. dietary study for adults. Toxaphene was year rat study in which 1.26 mg/kp/day The available data indicates that detected In 30 percent of the oils and fat was selected as the NOAEL and an toxaphene Is a potent carcinogen in samples for infants: concentrations uncertainty factor of 1ooO. animals. For thls reason and because ranged from 40 to 173 pg/kg. Residues of Toxnphene has been showa to be there Is some occurrcnce in drinking toxaphene ranging from 30 to 77 p /kg mutagenmic in the Salmonella water, an RMCL and a primary drinking were also ieported in 10 percent o! the minrosomal reverse mutation aasay, water regulation will be proposed. The vegetable samples and 80 percent of the with mutagenicity decreased by the RMCL will be based upon carcinogenic olln and fat samples for toddlers. addtion of active function oxidases. The effects and an RMCL of zero Is Recent USDA activity (1882-83) failed National Cancer Institute carded out a proposed. lo detect toxaphene residues in animal study (NCI. 1979. 8iOS68ay of mea! roducts. Toxaphene for Possible Carcinogenlclty; 23.2,4,6-TP Am%lent air studies conducted NCI Carinogenesis Technical Report 2,4,b-TP ~2-(2,4,6,-Trichlorophenoxy) between 197Cb1978 reported maximum Series No. 37, DHEW Publlcation No. propionic acid or silvex; CAS #93-72-1; toxaphene levels as high as 8.7 pg/m? (NIHl7W2) on the carcinogenicity of current MCL Is 10 g/l] is a herbicide However, because of substantially toxaphene in which male and female that ha6 been userrfor weed and brush reduced used rates since these studies, mice and rats were fed various doses of control on rangeland and rights of way. actual levels at this time are probably toxaphene added to the diet as an pastures, commercial or ornamental turf, considerably lower. acetone solutlon, 2 percent corn oil. It home weed control and weed control in Toxaphene has been detected in was concluded that under the conditions strearne and rivers and in drinking water and along canals and other waterways. of the bioassay, toxaphene was 2,4,6,-TPis soluble in water (140 mg/l in !wo States and in twenty-seven carcinogenic in male and female mice, systems tested by EPA. None of the at 26 'C). The environmental persistence causing increeed Incidences of of 2,4,5-TP Is expected to be relatively surface or ground water systems hepatocellular carcinomas in a dose Rnalyzed during the RWS contained short. Phenoxy acid herbicides undeQo related manner. The results also photolysis and bacterial degradation. detectable levels of toxaphene. suaeated that toxaphene was Compliance data from the National carcinogenic for the thyroid of male and In 1979, EPA issued an emergency Interim Primary Drinking Water female rats. In a separate study, with suepension order covering the use of Regulation did not report toxaphene in male and female mice (NCI, 1979. 2,4,&TP for weed and brush control in excess of the MCL. DiXW 7Q-832), increased incidencee of forests, rights of way, pastures, HealfhEffects,. Acute exposure to hepatocelluar carcinoma in male mice Irrlgatlon canals, and other waterways, toxaphene resuts In a variety of central were observed after 18 months of turfs and homes. "be suspension was nervous system effects, iircludinll toxaphene ingestion in the diet. The never lifted, and all registrations for salivation, hyper excltablity, behavioral IARC has classified toxaphene in Group herbicides contalning 2,4,5-TP are now changes and convulsions. The kidney, 2; inadequate evldence for canceled. While there is still limited use liver and testes are also affected by carcinogencity in humans and adequate of existing stocks of certain 2,4,5-TP acute exposure to toxasphene. The evidence for carcinogenicity in animals. products (non-suspended uses only], the critical target organ in chrcnic 01 Toxaphene has been classified in EPAs existing stocks period has expired for subchronic exposure la the liver. One- Group 82, according to EPAs Proposed most products. day assessments were calculated based Guidelines for Carcinogen Risk Analytical Methods. Analytical upon kidney and liver pathology as the Assessment, based upon the positive methods available for analyzing 2,4,5-TP critical endpoints. Using a LOAEL of 4 results in studies in rets and mice. in drinklng water include the mg/kg/day, an uncertainty factor of 100 EPA's CAC have derived estimates of derlvatization-gas chromatography and consumption of one liter (child) or risk of daily exposure to toxaphene in technique. two liters (adult) of water per day, 1-day drinking water based upon the incidence Human Exposure. No comprehensive numbers of 0.5 mg/l for !he child and of hepatocellular carcinoma from an data are available on the levels of 2,4,5- 1.75 mg/i for the adult were calculated Ingestion study in mice. Table 13 TP in the U.S. food supply. Data on [Lackey, R.W.1849. Observations on the summarizes the CAG risk estimate. levels of 2,4,5-TP on apples in 1975 Acute and Chronic Toxicity of EPA's MCL for toxaphene in drlnklng indicate the presence of residues in Toxaphene in the Dog, J. Industrial water, under the National Interim unwashed fruit of 97 pg/kg Ini!ially, Hygiene Toxicology. 31:117-128). Primary Drinking Water Regulations, is decreasing to 36 pg/kg after 4 months of Ten-day numbers were baaed on the 0.005 mg/l. This standard is based on storage. significant results of the Lackey (1848) the reported organoleptic effects of No data are available on levels of study. Minimal kidney and liver toxaphene at concentrations greater 2,4,5-TP In air. pathology were reported in do s than 5 pg/l (Sigworth, E.A. 1885. 2,4,5-TP has been found in dri,iking exposed to toxaphene at 4 mgfkg bw/ Indentifintlon and Removal of wnter in three States. Of eight surface day for up to 44 days. These effects Herbicides and Pesticides. J.Am.Water systems sampled in the NORS, one large were not observed at higher doses in Works Aaeoc. 67:1016). system was found to contain 0.02 pg/l other species. It is uncertain if these EPA's ambient water quality criteria 2,4,5-TP. In the NSP, 2,4,6-TP wa1 not effects occur within 10 days of exposure. for human health, considering lngestlon detected in any of the 105 surface water

S-074999 01~06'~12-NOV-8~-I~:27:41) F4701 rev. 8-14-85 Federal Reglsler / Vol. SO,-- No. 218 / Wedneeday, November 13, 1886 / Ropoeed Eulee 47007 systems semplod. None of the 21 surface (adult) of water per da , iO-day numbers mg/l) with 20 percent drinking water water systems sampled during tho RWS of 0.2 mg/l and 0.7 msjwere contrlbutlon. contained 2,4,5-TP in excess of the delermlned for the child and adult, minlnium quantification limit of 0.1 pg/L respectively. 24. Xylene Concentrations of 2,4,5-TP ranging The NAS (Drinkin Water and For the purposes of thio proposal. from 0.03 to 0.08 g/l were found in a Health, 1977. Vol. I) fI as calculeted an xylene is cons!dered to b3 the mixture USGS survey of thsl. .d drinking water AD1 for 2,4,5-TP based upon a Iwn-year (CAS # 1330-20-7) of three isomers collected from 15 suCqce water systems feeding study (Mullison, 1988. South (ortho-, CAS * 8-74: mete-. CAS * in Florida. Weed Conf. Proc. 19th Annual Meeting. 108-38.3: and para-, CAS * 2108-42-3). National compliance reports show Jacksonville, Floride, paflee 420-435) in Xylene isomerti arc slightly sduble 111 that one medium-sized surface system dogs In which 0.75 mg/kg/day was water and are soluble in alcohol. ether vlolated the MCL for 2,4,5-TP. selected as the NOAEL. Using this and man: lther organic liquids. Finished drinking water samples frm NOAEL and an uncertalntj lac!or of Xylene le used in aviation and 3 out of 127 water supplies sampled 111 1O00, the NAS calculated an AD1 of automobile gasoline, protective coatings. Florida contained 2,4,5-TP in the range 0.0076 mg/kg/day. in the synthesis of many organic of 0.04 lo 0.08 pg/L A USGS survey of The AADI will be determlned based chemicaln, pharmaceuticals and ground water supplies in Florida also upon the same study ueed by the NAS to *Atamins, and as solvents for many detected 2,4,6-TP at levels ranging from calculate the AD1 (Mullison, 1eeS. South preparations, including pesticides. 0*04pg/Ito 0.30 pg/L Week Conf. hoc. 19th Annual Meeting, Analytical Methods. Anulylical 2,4,5-TP has been found in hazardous jacksonville, Florida, pp. 420-4353. Using methods availeblo for analyzing xylene waste and in waste water. The 0.75 mg/kg/day as the NOAEL, an in drinking water include the purge and compound Is mobile and is widely used. uncertainty factor of 100 and trap-gas chromatography technique. HealfhEffecf8.2,4,5-TP is 2 consumption of llters of water per day, Human EX~OBU~B.No !nformtlticcl WHS contaminated to varvlng extents with an AADI of 0.28 mg/l has been available on the human intakc of xylene 2,3,7,&TCDD, a highly toxic dnt~j~mined. from food. The median level of o-xylene polychlorinated dibenzo-p-dioxin, A mutagenicity assay (Anderson, et In smblent air reportedly ranges from 0.4 Substantial differences in the toxlclty oi el., 1872.1. Agrlc. Food Chem. 20(3):849) pg/ma in rural and tcmote areas to 3 pg/ 2,4,6-TP have been reported, probably on 2,4,5-TP found that the compound did main source dominated areas. Median based upon the degree of contamination not cause point mutationa in histidine- of the compound. levels of m-and p-xylene (combined) requiring mutants of Salmonella range from 0.4 pg/m' to 73 pg/mJ in Single, oral exposure lo 2,4.5-TP at fyphimurium.Limited data are available high doses causes a variety of source dominated areas. Based on these on the potential carcinogenicity of 2,4,5- data. estlma!ed maximum daily intake physl )logical and biochemlcal effects TP. In one study (Innes, 1089, J. Natl. including depression, posterior quarter for adults in rural and source domineled Cancer Inst. 42:1101), chronic oral areas, respectively, would approach 8 muscle weakness, Irritation of the exposure to 2,4,5-TP did not slgnificanlly stomach and minor liver and kidney pg/day and 1.7 pg/day for all isomers Increase the lncldence of tumors at my (combined). damage in mammals. Subchronic site in mice exposed for 80-81 weeks, exposure to 2,4,5-TP in animals has while another study (Gehring and ilesto, The results of the CWSS indicated prcduced histopathologic changes in the 1978. Ecol. Bull. Stockholm. 27:122) also that approxlmately 3 percent of the liver and kidney, while chronic studies showed no increase in tumor incidence ground water systems contained have noted adverse effecta such as mild in rets or dogs exposed to 2,4,5-TP for 2 detectable levels of xylene while the degeneration and necrosis of years. However, these studies did not CWSS indicated that xylene was in 6 hepatocytes accompanied by !:levation employ the recent NCI bioassay percent of the surface water supplies. of SCOT and SGPT. procedure recommending the use of the The maximum detected level of The available data are inadequate to maximum tolerated dose and half of the contamination reported in federal and eetlmate a 1-day assessment for 2,4,5- maximum tolerated dose and thus it is state surveys was 750 pg/l in ground TP. Two unpublished studies by Dow difficult to reach a conclusion on the water and 5.2 pg/l in surface water Chemical (1982,1883) that described the carcinogenicily of the compound. 2.4,5- supplies. toxicity of 2,4,5-TP to rata and dogs were TP has been classifled in EPAs Group Health Effecfs.The prlncipal toxic examined. No effects were reported in D, according to EPAs Proposed effects of xylene are central nrrvous dogs administered 2 mg/kg/day 2,4,5-TP Guidelines for Carcinogen Riel< system disturbenccs, such as changes in In the diet for 89 days. Only one dose Assessment, based upon Inadequate numerative ability reaction time, short- level was employed in this study, and data from animal studies. term memory and the available description of this EPAs MCL for 2.4,5-TP in drinking electroencephalographic patterns. unpublished work provided no details water, under !he National Interim Xylene also affects the liver at very high on the extensiveness of pathologic Primary Drinking Water Reguletlons, Is concentrations. A 1-day number was extiinhation. In a com anion study, rata 0.01 mgll. This standard is based upon a calculated for xylene bpsed upon an administered 5 mg/hgfday of the sodium NOAEL of 0.9 mg/kg/day, with an inhalation study In human volunteers salt of PGBE ester of 2,4,5-TP for 90 days uncertalnty factor of 50 and the (Camberale, et al. 1978. Exposure to had an hcreaae in relative weight of the assumption that 20 percent of the total Xylcne and Ethylbenzene. 111. Effects on liver and kidney with "histopathologic intake 1s vla driiiking water. Central Nervous Functions. Scan. j. changes" in both. Exposure to 2,4,5,-TP at high dose Work Environ. Health. 4:2W). In this Of these two studies, the study In the levels results in a variety of chronic study. o NOAEL was determined at an do that identified a NOAEL of 2 mg/ adverse health effects. Because this inhalation concentration of 1300 mg/ma kgfday was used to calculate a 10-day contaminant also has been detected in as for approxima:dv one hour. Using assessment. Using the NOAEL of 2 mg/ several drinking water systems, an 1300 mg/ms the NOAbL fGr a I-day kglday, an uncertain1 factor of 100 RMCL and a primary regulation will be exposure, an uncertainty tLctor of 10 based upon an animar study and proposed. An RMCL of 0.052 mg/l le and consumption of 1 liter (child) or 2 consumption of 1 liter (child) of 2 liters proposed based upon the AADl(O.2C litera of water (adult) per day, I-day

S-074999 OlO7(06~t2-NOV-85- t5:27:43) F4701 rev. 6-14-85 47fW Federal Reglster / Vol. 60, No. 210 / Wedneaday, November 13, 1986 / Propoaed Rules numbem of 12 mg/l for a IO kg child and mg/l assumlng 20 percent drinking water Health Effects.lnsufficien t 42 mg/l for a 70 kg adult were conltibutlon. toxicological data are available on the calculated. C. RMCLS Not Proposed short-term effects of atrazine to Insufficient Ingestion toxicologlcal calculate 1-day or mday assessments. data are available to calculate 10.day 1. Atrazine Atrazine appears to have low chronic numbers. Howevor, 10-day numbers Atrazine I&chloro-N-ethyl-N'-(i- toxldty in animals. In a 2-year chronic were calculated baaed upon a study feeding study at 100 mg/l In the diet of (Carpenter, et al. 1975. Petroleum methylethyl)-1,3,btrlazine-2,4-diamine: CAS ft 1912-24-0) le e herbicide and a rets, no gross or microscopic signs of Hydrocarbon Toxicity Studles. V. toxicity were qbserved. The NAS Animal and Human Response to Vapors plant-growth regulator. It is slightly soluble in water under normal (Drinking Wuter and Health. 1977. Vol. of Mixed Xylenes. Toxlcol. Appl. I) calculated an AADI tor alrazlne based PhRrmacol. 33:ti43) In rats exposed by conditions (33 mg/l at 27 'C). Its vapor pressure le low (1.4xlO-'mm Hg at 30 upon iin 80 week study (Innes, J.R.M., et inhelatlon to mixed xylene at 2ooo mg/ el. 1969. Bioabeay of Pesticides and m3for 8 hours/day (5 days/week) for up 'C). Domeslic tis- of atrazine is estlmated to range between 100 and MI0 Industrlal Chemicals for Tumorlgenicity to 13 weeks. No significant effects on in Mlce. A prellmlnary note. J.Net. blood chumistry or tissue histology were rnilllon pounds annually. About 88 percent of the domestically supplied Cancer Inst. 42: 1101-1114) in mice In reported as a result of the xylene which a dose of 21.5 mg/kg/day was exposure. Using 200 mg/m' as a NOAEL, atrazine is used on corn and soybeans. Analytical Methods. Analytical shown to result in an incidence of an uncertainty fdctor of 100. and hepatomas of 4.24 percent In controls 1 2 methods available for analyzing consumplion of liter (child) or liters and 6.8 percent In atrazine treated IadLlt) of water per day, mday numbers atrazine in drinking water include the animals. An AD1 of 0.~215mg/kg/da of 7.8 mg/l for a 10 kg child end 27 mg/l solvent extraction-gas chromatography was determined based upon 21.6 mgrkg/ for a 70 kg adult were calculated. lechnlque. A provlalonal AADl for xylene day as a LOAEL and an uncertainty Is Human Exposum Very little data are factor of 1,oo0 based on animal study. based on an inhalabon study (Jenklns, ~t available on atrazine levels In food. The Baaed upon the NAS ADI. a providondl el. 1970. Long-term Inhalation Studies on 1971 and 1972 National Soils Monitoring AADl of 0.75 mg/l was calculated, Benzene Toluene, o-Xylene and Cumene Program reported that 1 percent of grain on Experimental Anlmals. Toxlcol. Appl. assuming consumption of 2 litem of and vegetable samples from areas water per day. Pharmecol. 1&815) In rato, gulnea pigs, where atrazine Is used contained monkeys and dogs. In this study, Atrazlne has not been shown to be atrazine in excess of the minimum mutagenic in standard essays with animals we1 e exposed at a dose level of detection level of 10 pg/kg. Atrazine 377 mg/m'continuously for 80 dayn. No residues are permitted on certain crops. microorganisms and ctudiee on the etatietically slgnlficant effects were If all foodc contalned atrazine residues carclnogenicity of the compound have observed wlth respect to body weight, up to the tolerance level, an adult might shown inconclusive results. The LARC hematology and histopathological have a daily atrazine residue intake of has not evaluated the carcinogenicity of examlnation of treated animals. Using up to 77 pg/day. atrazlne. Atrazine has been classified in EPA's Group D, according to EPA's 337 mg/m'as thc NOAEL an No information is avallable on the uncertainty factor of loo0 based upon an Roposed Guidelines for Carcinogen level of atrame in ambient ah. Risk Assessment, based upon animal etudy with few animals per dosc One large surface water supply level, and consumption of 2 liters of Inadequate evidence from animals system sampled In the NORs contained studies. water per day, a provisional AADI of 2.2 0.1 pg/l atrazlne In ita finished drinking mg/l was calculated. Only the Inner study is available on The estimated concentration for water. During the NSP, 28 percent of the the health effects of atrazine and this surface water systems contalned study is Inadequate to serve as the basis detectio.1 by taste and odor in surface atrazine in excess of the quantlficailon water le 0.3 to 1.0 mg/l (Middlcton, et el. for the RMCL Other studies submitted llmit of 0.1 pgll. The range of posltlve 1950. . Am. Water Works Assoc. W.21). to EPA's Office of Pesticides Programs Litt1 e dota are avallrble on the values was 0.1-2.9 &I. have been seriously questioned because carclnoganiclty of rcylene. One stud)* Atrazlne was detected In six samples of unsclentific laboratory techniques. examined the dermal effects of xylene from drinking water supplies drawn Due to the peuclty of the toxicological and concluded that xylene was not a from Northwestern Ohio rivers. Atrazine data, an RMCL and primary regulation skln tumorigen. A long-tem levels ranged from 0.087-15.9 pg/I; the are not being proposed for atrazine. carcinogenicity bioassay la presently average reported value was 6.76 &I. Atrazine will be reexarnlned for being conducted by the National Atrazlne concentratlons were regulation when the toxicology data TOXICOIO~~Progranr. Mice and rets have detected during a study comparing the base is expanded. been treated, hit data from this study effectiveness of various types of water are not yet available. Xylene has been treatment for the removal of herbicides. 2.2,3,7,&Tetrachlorodi benzo-p-dioxin classified in EPA's Group D, accordlng Average concentratlone of atrazine for 2,3,7,S'ietrachlorodibenzo-p-Dioxin to EPAs Proposed Guidelines for the three supplies were 0.90,2.1 and 3.31 (2,3,7,&TCiJD: CAS d# 82Wl0-2) is not Carcinogen Rlsk Assessment, based pg/L respectively. Peak concentrations manufactured purposefully; It IRformed upon inadequate data from animal were 1.22.5.2 and 7.84 pg/l, respectively. an a contaminant or impurity during studies. Atrazi1.3 was found in a major water chen;ical production or chemical Exposure to xylene at hlgh dose levels ~u~plyon the Misslasippi River at 4.7- pyrolysis. 2,4,S-TrichlorophenoI (2,4,5- hRs been shown lo result in chronlc 1.1 pg/L TCP), a chemical formed from 1,2,4,5- toxic effects. For this reason and Two ground warn systems analyzed tetrechlorobenzene, is contaminated because there has been significant in the NORS contelned traces of wlth 2.3,7.BTCDD. 2.4,5-TCP is, in turn, occurrence of this contaminant in water, atrazine. Ground water supplies in three wed in the production of several an RVCL end a prlmary regulation will mldwestern States tested positive for herbidices, including 2,4,5- be proposed. An RMCL of 0.44 mg/l le atrazine, wlth concentratlone typically trichloropbenoxyacetic acld (2,4,5-T) proposed, based upon an AADl of 2.2 In the rang: of 0.8 pg/L estere, and Silvex. Therefore, 2,3,7,8

Sa4999 OIO8(~~12-NOV-8S-tJ:27:4~) F4701 rev. 61485 - Federal Regieter / Vol. 60, No. 210 / Wednesday, November 1085 / Proposed Rules 13, -- TCDD may be a contaminant of these the extent of dioxin (prlmorily 2,3,7.& Schantz, et el. (Schanlz, S.L..D.A. I herbicides. Additionally, TCDD may be TCDD) contamination throughout the Barsotti and J.R. Allen, 1H7R. formed as an impurity during the wintry. The stralegy provides a Toxicologicel Effects Produced in Non- pyrolysis of chlorinated phenols, systematic framework under which the human Prlmates Chronically Exposed lo chlorinated benzenes, and Agency will (1) study the nature of Flfty Parts per Trillion 2.3.i.H- polychlorinated diphenyl ethers. dioxin contamination throughout the Tetrachlorodibenzo-p-dioxin(TCDD). Anal tical Methods. Analytical U.S. and the r!sks to people and the Toxicol. Appl. Pharmecoi. 4B:A180). method s available for analyzing 2,3,7,& environment, (2) clean-up dioxin- represents a LOAEL for etiverse TCDD in drinking water include the contamlnatcd sites that threaten publlc reproductivs effects. A LOAEL of 0.001 solvent exraction-gas chromatography health, (3) find ways to prevent future ug/kg was selected. with en unccrtointy mass spectrometry technique. contamination, and (4) find ways to factor of 1.o00 bas :d upon an animal Human Exposure. In theory, 2,3,7,8- destroy or dispose of existing dioxins. study and consumption of 2 liters of TCDD could occur In food ao a rosult of Heolth Effects. 2,3,7,&TCDD Is water per day, resulting In tin AADl of contamination of plant crops by readily absorbed by mammala following 3.5 x 10-'mg/l. herblcldes such as Silvex or 2,4,5-T, either oral or dermal exposure and is The NAS (Drinking Wolrrr and coiisumpllon by livestock of 2,3,7,6- rapldly dlstrlbuted to tissues with a high Health, 1877. Voi. I) calculoted tin AD1 TCDD-contaminated forage or lipid content, The llver represento a of 0.0001 ug/kg day boned on il 13 week concentration of residue8 through the major site of acciimulation in many oral treatment study in rdls (Kocil- , R.J., food chain. However, data on actual speclee. Metabolism of 2,3,7,&TCDD P.A. Keeler, C.N. PHrk, and P.]. CehrinR. occitrrence in food are rare. TCDD has occurs slowly, with the polar 1978.2,3,7.8-Tetrachlorodit~enzo-p- been reported at levels of 4-70 ppt in the metabolites excreted in the urine. dioxin (TCDD): Results of H 13-week fat of cattle that had grazed on land Charecterlstic non-carcinogenic Study in Rats. Toxlcol. Appl. PherrnHcol. treated with 2,4,5-T. 2,3,7,&TCDD has effects resulting from exposure to 35553-574) using a NOAEL of 0.01 ugl also been detected In several specles of 2,3,7,&TCDD include thymlc atrophy kg/day. an uncertainty factor of 100 and commercial and non-commercial fish in and weight loss. In certain speciee, liver consumption of 2 liters of water per day. severel rivers and lakes in the United damage is a mejor pathological effect. States. Levels of TCDD reported in fish One-day assessments were calculated Mutagenicity tests have shown and shellfish range from 1-700 ppt. The based on a study in rats (Turner, J.N. conflicting results with inconchsive evidence as to the mutagenicity of estimated maximum daily intake of and D.N. Collins. 1983. Liver Morphology 2,3,7,&TCDD for individuals who in Guinea Pigs Administered either 2,3,7,8-TCDD. Animol studies have regularly consume contaminated fish Pyrolysis Products of a Polychlorinated demonstratad the compound to be a from the Great Lakes region might range Biphenyl Traneformer Fluid or 2,3,7.8- potent animal carcinogen. Oral from 0.38-8.4 ng/day, telrachloro-dibenzo-p-dioxins.Toxicol. administration of 2,3,7,8-TCDD. either in Data on ambient air levels of 2,3,7,a Appl. Pharmacol. 07:417429) where a the diet or by gavage, results in the TCDD are limited. TCDD has been single'day oral dose of 2,3,7,&TCDD productim of hepatocellular carcinomas found in ambient air under special induced liver changes in femele guinea In female rats and both sexes of mice. in conditlons. Air levels, ranging from 0.08 pigs. Using a LOAEL of 0.1 pg/kg, an the National Toxicology Program ng/m* to 0.07 ng/m5, have been reported uncertainly factor of Lo00 and bioassay (NTP. 1980. Bioassay of 2.3.7.8- following agricultural application of consumption of liter (child) or 2 litera Tetrachlorodibenzo-p-dioxinfor Silvex. In addition, 2,3,7.&TCDD was (adult) of water er day, 1-day numbers Possible Carcinogenicity [Gavage detected at an average level of 1,100 ppt of 1.0 x lo-' pgl for a 10 kg child and Study). Carcinogenesis Testing Program. in air at a disposal site near 3.5 X lO-'pg/l for a 70 kg adult were NCI, NIH, Bethesda. MD and NTP. Jacksonville, Arkansas. Atmospheric calculated. Research Triangle Park, NC. Pub. No. emissions from munlclpal incineroton, Ten-day assessments were calculated 82-1705), rats and mice were dosed and from certain flres have been by dividing the one-day assessments by twice weekly by gavage with 2,3,7.8- reported; however, data on ground level ten. Consequently, 10-day numbers of TCDD in a corn oil-acetone solution. In concentrations of 2,3,7,&TCDD were not 1.0 x lo-' g/l for a 10 kg child and 3.5 male rats, a dose-dependent increase in available. X lo-' pg/;lfor a 70 kg adult were the incidence of follicular-ce:l adenomas Dioxin has not been detected In calculated. or carcinomas of the thyroid was drinking water, as the physical/ A provlslonal AADI has been observed. In female rats. obserwd chemical charecteristics of the calculP.;ed that Is consistent with that increases in the incidence of compound suggest that it is relatively developed by the Agency as indicated subcutaneous tissue fibrosarcomas, Immobile and thus would not be by the EPA, Ambient Water Quality adrenal cortical adenomas and expected to be found in drinking water. Cr'.leria for 2,3.7,&Tetrachlorodibenzo-p- hepatocellular carciiiomas were Data are not available showing dloxin (1' 3. EPA, 1884. Ambient Water observed only in the high dose group. occurrence in surface or round waters. Quality Criteria for 2,3,7,& Other studies have reported squamous Dioxin has been identified at more Tetrachlorodiobenzo-p-dloxin.EPA 440/ cell carcinomas in both sexes of rats than 32 hazardous waste sites tis(Mo7) where It concluded that the and folliculwceil adenomas of the designated in complaints and consent 0.001 ug/kg dose in a three-generation thyroid in both male and female mice. . decrees under the Comprehensive reproduction etudy in rats by Murray, et A number of reports and Emergency Response Compensation and al. (Murray, F.J., F.A. Smith, K.B. epidemiological studies have attempted Liability Act of 1980 (CERCLA) and the Nitsckle, C.G. Huniston, R.J. Kociba, a.id to relate 2,3,?,8-TCDD exposure to National ContIngency Plan (40 CFR Part B.A. Schwetz. 1979. Three-generation human health effects. 2.3.73-TCDD has 300). The concentration of dioxin rn the Reproduction Study of Rats Given been implicated as the caustive agent soil at one site was reported at 0.5 mg/ 7,3,7,8Terachloro-p-dioxin(TCDD) in for chloracne. hyperpigmentation, kg and at levels of 20 mg/l In nor.. the diet. Toxicol. Appl. Pharmacol. altered liver function and porphyria aqueous phase liquids in the dnmp. M):24-261), in conjunction with culanea tarda In humans. In additlon, In Ds. zmber 1983, EPA announcod a :sproductlve effects noted at 0,0015 ua/ queetions have been raised regarding 8 Natlof!d! Dioxin Strategy to determlne kg In a Ilmited study with monkeys by possible relationship between 2,3.7,8-

S-074999 0 t09\06~IZ-NOV-85- ~2~47) F4701 rev. Br14-85 - 47010 Federal Register / Vol. W, No. 218 / Wedneeday. November 13, 1985 / Proposed Rulee

TCDD exposure and cancer. The those used for the risk assessment for in drinking water include the solvent available studies do not establish a 2.3,7,&TCDD previously described. The extraction-gas chromatography definite relationship between 2,3,7,& FDA has issued a Health Advisory technique. TCDD and the development of tumore In (FDA. 1983. Statement by S.A. Miller, Human Exposure. In CIIA's humans, although an association has Director. Bureau of Foods, FDA, before compliance program report for FY 77 on been suggasted with soft-tissue the Subcommittee on Natural Resources, pesticides and metals. endrin was sarcomas. lymphomas, and stomach Agriculture Research and Environment, detected in 2.1 percent of the samples cancer. The IARC have classified 2,3,7,& US. House of Representatives, June 30) tested. In the FDA FY 79 total dietary TCDD in Croup 28; inadequate evidence in which fish containing >50 ppt 2,3,7,& study for adults and infants. no endrin for carcinoge;licity in humans, sufficient TCDD should not be consumed and fish was detected in any of the foods evidence ior carcinogenicity in animals containing c25 ppl2,3,7,&'i'CDD do not sampled. One residue was detected in and inedequate evidence for activity In pose a serious health concern. A an oils and fats sample at a level of 1 short-term tests. 2,3,7,8-TCDD has been tolerance of 0.05 ppm for pg/l for the toddler diet. According to clossifiad in EPA's Croup 82, according hexachlorophene methylenebis (23,s the USDA, i:i 1982-1983,0.3 percent of to EPA's Proposed Culdellnes for trichlorophenol) in or on feedstock the fat tissue from various animal Carcinogens Risk Assessment, based cottonseed has been set with the species Mended for human upon positive results in studies in rats condition that the technical grade consumplion contained endrin levels and mice. material contain no more than 0.1 ppm, ranging from 0.014.10 pg/kg. EPA'a CAC has derived estimates of 2,3,7,&TCDD (40CFR 160.302). Tnlerances for residues of endrin as risk from exposure lo 2,3,7.&TCDD In 2,3,7,&TCDD has not been detected in set by EPA's Office of Pesticide drinking water based upon a drinking water supplies. The compound Programs, in or beets, broccoli, brussels carcinogenicity study consisting of le not mobilo in runoff or soils and has sprouts, cebbage, cauliflower, lifetime feeding of 2,3,7,&TCDD In not been found in ground water or cottonseed, cucumbers. eggplant, female rats [Koclbe, R.J., D.C. Keyes, J.E. surface water that Is a potential source pepper, potatoes, squash and tomatoes Berger. et el. 1977. Results of a Two-year of drlnklne water. Due to the limited are 10 ppm. Chronic Toxicity and Oncogenicity occurrence and potential for occurrence Ambient air studies between 1970- Study of 2,3.7,&Tetrachlorodlbenzo-p- In drinking water, an RMCL and primary 1975 reported endrin levels as high as dioxin in Rats. Toxicol. Appl. regulation is not being proposed for 38.3 ng/m'. Pharmacol. 48:279-303). A 9.1 of 2,3,7,&TCDD. Endrin is rarely detected in drinking 1.58x10*(mg/kg/day)-' was calculated Question for Comment: water. The compound has been detected by the multi-stage model for this risk 1. Are there any data to suggest that in three aurface water supplied drinking assessment. This is the geometric mean 2,3.7,&TCDD is known or likely to be water systems in one State. None of the of 2q.1 calculations baped on the review found in drinking water supplies? surface or ground water systems of tissue slides by two independent Endrin analyzed during the NSP or the pathologists and corrected for early 3. RWS Endrin (1,2,3,4,10.10-hexachlorod,7- contained detectable levels of endrin. mortality. The OHEA risk estimate is National compliance reports with the shown in Table 13. epoxy-1,4.4a, 5,8.?,8.8a-octa-hydro-i.4- CAG (U.S.EPA. Health Assessment endo,endo-5.8-dimethanoaphthalene; NIPDWR show that no system sampled Document for Pol) chlorinated Dibenzo- CAS # 72-204; current MCL is 0.2 pg/l) reported endrin in excess of the MCL of 0.2 rng/l. p-dioxin, May 1984. EPA-600/8-84- is a commercially used insecticide and 014A) has also derived risk estimates for rodenticide. The solubility of endrin in Health Effects. At high dose levels, 2,3,7,&TCDD based on the same study water is 0.25 mg/l. Endrin is persistent endrin has been shown to accumulate in using other modela. The comparison for and is concentrated through the aquatic liver, brain, kidneys, and fat. while at a risk estimate from exposure to a food chains. lower dose levels endrin is quickly 2,3,7,&TCDD level of loeLuglkglday Is Endrin was only widely used in the metabolized and eliminated from the given below: US. The EPA issued a notice of body. The major toxicant in mammals Is rebuttable presumption against considered to be the metabolite 12- wP-yJ=a=amOI~~~ registration and continued registrvtion ketoendrin. (RPAR) of endrin-containing products in One-day assessment were calculated 1978. It included three risk for endrin based upon a study in squirrel presumptions-risk of significant monkeys (Revzin, 1988. Effects of population reductions of non-target Chronic Endrin Administration on Brain organisms, acute toxicity to wildlife, and Electrical Activity in the Squirrel teratogenicity. After review, the Agency Monkey. Fed. Roc. 27:897) where 0.2 'Bomm0d.h Id.nbulrnuna. determined that the offsetting economic, mg/kg endrin was administered daily 'Used umn PiMOclb. 6- OI p.Iwogy. cvmel.6 IQ for 7 days and alterations in the -My. social or environmental benefits were EEG %red upql Sorn MOW#d or-. cvmelrd )a not great enough, and endrin was were recorded. No effects were noted at .ucr -lr*. cancelled for a number of uaes and this dose for shorter term exposure. The EPA water quality criterion for registration for new uses of endrin were Using 0.2 mg/kg/day as the NOAEL for 2,3,7,&TCDD for carcinogenic endpoints denied. Endrin is presently registered 1-day exposure, an uncertainty factor of (U.S. EPA. 1984. Ambient Quality only for the control of cutworms, 100 and consumption of 1 liter (child) or Criteria for 2,3,7,&Tetrachlorodlbenzo-p- grasshoppers and moles: however, the 2 litera of water (adult) of water per day, dioxin. EPA 440/&8rM07) Is 1.3 x10-6 sole Endrin manufacturer has ceased 1-day numbers of 0.02 mg/l for a IO kg g/l based on an estimated human production for use in the US. child and 0.07 mg/l for a 70 kg adult hetime cancer risk of 1x 10-6 and Environmental concentrations of endrin were calculated. assuming daily consumption of 2 litem appear to be decreesing due to these use Ten-day assessment were calculated of water and 8.6 8 of fish and shellfish, restrictlono, based upon a study (Nelson, et ai. 1866. The study and etatistical model used for Anal thlMethods. Analytlcal Serum Alkuline Phoaphaluse Levels, this risk aeeedsment were the same as metho(Y s available for analyzlng endrin Weight Changep, and Mortality Rates of

S-074999 01 10(06~12-NOV-8S-IS:27:49) F4701 rev. 614-85 Federal Register / Voi. SO, No. 219 / Wednesday, November 13,1985 / Proposed Rules 47011 - _-----..__-

Rats Fed Endrin. J, Agric. Food 8 Cheni, EPAs ambient water criterion for Humon Exposure. Hexachlorobenzene 4:efM)in rats exposed for 1 or 2 weeks to endrin (U.S. EPA. 1980. Ambient Weter has been a contaminant of concern 5 ppm (0.05 mg/kg/day] endrin in the Quality Criteria for Endrin. EPA/440/5- because of its occurrence in human diet. The body weight of tho exposed 80-047) for humon health is 0.001 mR/I. tissue and the milk from nursing animals was decreased relative tt This was based upon the same study mothers. The compound hils hen fnund controls. Using 0.05 mg/kg/day as a which wus used to dericr: the In adiposo tlssue end milk of cattlr! NOAEL an uncerlolnty factor of 100. provisional AADl ana a value of 0.001 raised in the vicinity of industrialized and consumption of 1 liter (child) or 2 mg/l was recommended because it was regions in Louisiana. and in adipose liters of water per day (odult). 10-day the maximum allowable concentration tissue of sheep in western Texas ond numhers of 0.00~mg/l for a 10 kg child proposed by the Public Health Service California. ttexachiorobenzen~has HISO and 0.018 mg/l for a 70 kg adult were for drinking water. The WHO (1973) been found in fish and birds. calculetad. established as a guideline a maximum Iiexochlorobenzene hiis been found in A provisional AADl for endrin was intake of 2 pg/kg/day, or 138.2 pglday, ambient air around production sand derived based upon a feeding study for a 89.1 kg person. The WHO has not waste disposal sites. (Treon. et al. 1955. Toxicity of Endrin for established a drinking water guideline Limited information is available on Laboratory Anirnols. 1. Agric. Food & for endrin. levels of hexachlorol)enze.ie in finished Chem. 3:842) in which dogs were The MCL, under the National Interim drinking wntcr supplies. exposed for 18.7 months to 1,3. or 4 ppm Primary Drinking Water Regulations, is t tnxach\orolenzc!ne wIis dc\octed in a endrin in the diet. Dased on measured 0.002 mg/l. The provisional AADl is Rcglonril survey in two finished wtlter food intoke, the daily dose varled Iron. slightly higher than the interim MCL due supplies ut levels of 4 and 6 ng/I. In the 0.045 to 0.12 mg/kg bw for the 1 ppm to the fact that the ptovisional AADl le NSP, the compound WBS not detected. group. 0.12 to 0.25 mg/kg bw for the 3 calculated based on the measured food Health Erfecr. tlexochlorobenzcnc is ppm group and 0.15 to 0.21 mglkg bw for intake of a dog, while the MCL was readily absorbed and distributed to the 4 ppm group. Increases in heart and calculated based upon the assumed food tissues that have high lipid content. The kidney weights were noted at 3 and 4 consumption of a dog, both based upon adipose tissue uccumuletes the greutcst pprn but not at 1 ppm. Using 0.WS mg/kg the same study (Treon, et el. 1955. concentro tions 01 hexachlorobenzcne. bw (1 ppm) as the NOAEL. an Toxicity of Endrin for Laboratory although bone morrow and skin also uncertainty factor of loclo based upon an Animals. J, Agric. Food & Chem. 3:842). accumulate the compound. animal study with few animals per dose Endrin is rarely detected in drinking Hexachlorobenzene is metabolized level, and consumption of 2 liters of water and has been cancelled for new slowly into other chlorinated benzenes, water per day, a provisional AADl nf uses. The compound is not considered to chlorinated phenols and other minor 0.002 mg/l was calculated. be very mobile and thus EPA is not metabolities. The excretion of Endrin was not shown to be proposing an RMCL for endrin. hexachlorobenzene is characterized by mutagenic in microbial systems with or Question for Comment: an initial rapid phase followed by il very without microsomal activation. The 1. Is there sufficient occurrence and slow phase. potential carcinogenic effects of endrin potential for occurrence in drinking Chronic toxicity studies in animals were evaluated in several animal water to propose an RMCL foe endrin? have shown a significant increase in studies. The results were negative in liver and kidney weights in 4. Hexachlorobenzene four studies, including the National hexachlorobenzene-trealed ariimals. ns Cancer bioassay (NCI. 1979. Bioassay of Hexachlorobenzene (CAS t 118-74-1) well as hepatic and renal lesions. Endrin for Possible Carcinogenesis. has a vapor pressure of 1.09 x mm Increased prophyrin levels in the liver Tech. Rep. Ser. 12. NCR-CGTR-12). Hg (20 'C). It has a vqlow aqueous and the urine have been reported in The only study (Deichmann. et al. 1970. solubility (e ug/l at 25 'C). several species. Tumorigenicity of Aldrin. Dieldrin and Hexachlorobenzene is no longer Porphyria cutanea tarda (PC?') has Endrin in the Plbino Rat. Ind. Med. produced in the United Stales. However, been associated with exposure of 39:426) reporting positive results was a approximately 2 to 5 metric tons of humans to hexachlorobenzene. An rat study in which endrin was hexachlorobenzene are generated epidemic of hexachlorobenzene-induced administered at concentrations of 0,O.l. annually as a waste byproduct of PCT occurred in Turkey, from expobure 5,2O or 25 ppm. The total number of chlorinated solvent and pesticide during 1955 to 1959 to contaminated malignant tumors was increased in all production. The primary use of seed wheat used for food. It has been exposed groups. No more than 2 tumors/ hexachlorobenzene in 1972 was as a estimated that 0.05 to 0.2 g of group, however, were reported for one fungicide. The majority of these hexachlorobenzene was consumed per site. Moreover, no dose response was formulations are no longer produced. day. PCT is a disease of disturbed apparent with the greatest riwnber of Other industrial uses have included dye porphyrin metabolism manifested by tumors occurring in the 0.1 pyn group. manufacturing, an intermediate in cutaneous lesions and The NAS (Drinking Water and Health, organic synthesis, porosity controller in hyperpigmentation. Follow-up studies 1977. Vol. 1) have stated that there are the manufacture of electrodes, a wood conducted 20 to 25 years die- tha onset insufficient data to permit a statistical preservative and an additive in of 4orphyria showed lhot II few patients extrapolation of cancer risk for endrin pyrotechnic compositions for the stili had active porphyria. whereas and that endrin Is a suspect animal military. Since hexachlorobenzene is no greater Illan 50 percent exhibited carcinogen. The IARC have not longer produced in the United States, hyperpigmentation. scarring and other addressed the carcinogenicity of endrin. commercial uses of hexachlorobenzene signs of hexachlorobenzene toxicity. Endrin has been classified in EPAs have virtually ceased. Hexachlorobenzene residues were tils0 Croup E. according to EPAs Proposed Analytical Methods. Analytical found in the blood. fat or breast miih of Guidelines for Carcinc,en Risk methods available for analyzing some patients. Assessment, based upon the negative hexachlorobenzene in drinking water One-day and 10-day essessments results from four studies including the Include the solvent extraction-gas were calculated based on a study NCI bioassay. chromatography technlque. (Kuiper-Goodmen. et el. 1977. Subacute 47W2 Foderal Register / Vol. 60, No. 210 / Wednesday, November 13, 1985 / Proposed Rules

Toxicity of t lexachlorobenzene in the hexachlorobenzene/kg body weight/ No data were found on the levels of Rat. Toxicol. Appl. Pharmacol. 4r):524. day, theee estimates are as follows: simazine in air. M9) where porphyrin. liver lesions and Simazine has been reported in other toxic effecrs were found in rats fed drinking water from surface supplies. In hexachlombenzene for 15 wceks and the NSP, conducted from lune 1877- held to 48 weeks. Uning a NOAEL of 0.6 March 1081,12 perctrit of finished mg/kg, an uncertainty factor of 100 and Mb4U-W ...... 2.7~lO-*(m) (2.2 x Wyb) drinking water samples collected from consumption of 1 liter (child) or 2 liters ROM ...... 3.8x 10'. surface water systems contained fadult) of water per day, 1-day and 10- (1.3x 10-1') w*bd ...... lPXlO', simazine; levels ranged from 0.14.4 pg/ day assessments of 0.050 mg/l for a IO (2.6X lo-') I. kg child and 0.175 mg/I for a 70 kg adult OMhn ...... 2.7~10-8 (22X 10-.) Levels of simazine ranging from 0.026- werc calculated. Wrcr w. lush ...... wunc@ag8...... 1.7~10-1 0.883 pg/i were detected in five drinking An AADl was calculated for (1.4x 10') water samplcs collected from a surface RQbn ...... 8.2xlW' hexachlorobenzene based upon a 130 (4.1 X lo-') water supply in one State during peak week feeding study in rats (Arnold, et al. wI&ll ...... 1.0x10-, periods of pesticide usage and maximum 1083. Long-term Toxicology of (1.3 x 10'1) onehn ...... 1.7~10-a pesticide export. Hexachlorobenzene in the Rat. In (1.4x lo-') Simazine concentrations reported for preparation). A NOAEL of 1.6 ppm drinking water samples collected from (0.084 mg/kg/day) was selectod based three treatment plants in another State upon livcr and kidney lesions and in 1983 ranged from 0.077-0.30 pg/l; increased mortality at higher doses. An The WHO guideline for peak concentrations ranged from 0.13- uncertainty factor of 100 was applied hexachlorobenzene (1984) le 0.01 pg/l 0.63 pg/l for the three reports. and consumption of 2 liters of water per based upon a risk of one additional case Simazine has also been found in day, reeultind in an AADl of 0.029 mg/l. of cancer per 100,ooO population, ground water. One of the 12 yound Hoxachlorobenzene has not been assuming a daily consumption of 2 litere water systems sampled In 'iie NSP of drinking water. shown to be mutagenic in the contained 1 pg/l. Six out df 188 wells in Solmonella histidine reversion assay, Hexachlorobenzene has rarely been California were found to be but wa8 reported mutagenic in a yeast S. detected in drinking water and the contaminntad at levels between 0.5-3.5 compound is not considered to mobile. cerevisioe assay. Hexachlorobenzene PS/I. has been shown to be carcinogenic in For these rea.sone, EPA is not proposing Health Effects. There is a lack of data animal studies, showing an increased a primary rqulation for the compound. on the health effects of simazine in incidence of malignant tumors of the Question im Comment: aiiimals and humans. In one study (U.S. liver in hamsters and rats, as well as 1. 1s there sufficient occurrence and EPA, 1978. Draft Report, lnitial Scientific inducing hepatomas in mice, rats and potential for occurrence in drinking and Microeconomic Review, Simazine. hamsters. water to propose an RMCL for Office of Pesticide Programs, EPA The IARC has classified hexachlorobenzene? Contract No. 8801-1904), simazine fed hexachlorobenzene in Croup 2B 5. Simazine to rats for 2 yeam at 1.0,10 and 100 mg/l inadequate evidence for carciriogenldty did not produce any difference between in humans and Rufficient evidence for Simazine [&chloro-N,N-diethyl-i,3,5- treated and control animals in gross carcinogenicity in animals. triazlne-2,4-diemine; CAS # 122-34-9) is appearance or behavior. Hexachlorobanzene has been classified a herbicide applied to field crops and on The NAS (Drinking Woter and in EPAe Croup B2, according to EPAs non-agricultural sites. Irrigation or Health, 1977. Vol. 1) calculated an AD1 Proposed Cuidelines for Carcinogen rainfall moves the chemical into the root for simazine based upon an 80 week Risk Assessment, based upon positive zone of weeds where it is actk. It may study (EPA, No. 0841-1804) in mice in results in studies in rats, mice and also be used BB an algacide ur to control which a dose of 215 mg/kg/day was hamsters. submerged weeds. Because simazine shown to result in an incidence of The NAS [Drinking Water and has a low vapor pressure, there is little hepatomas of 4.2 percent in controls and Health. 1983. Vol. V) calculated upper 95 tendency for simazine to enter air 6.8 percent in simazine treated animals. percent limits of cuncer risk based on directly during and following An AD1 of 0.215 mg/kg/day was carcinogenicity data in a study with application. spillage or dlsposd. In the determined based upon 215 mg/kg/day male and female mice. In the external U.S., approximately 81 percent of as a LOAEL and an uncertainty factor of review draft of the EPA Health simazine is applied in commercial 1,OOO based upon an animal study. Assessment Document for Chlorinated agricultural operations; 39 percent ie Simazine was negative in Benzenes (April 1984, EPA-€m/&84- applied to non-agricultural siten (aquatic mutagenicity studies with four strains of 015A), the CAC has calculated risk applications included). Salmonella typhimurium and the results estimates based on hepatocellular Analytical Method. Analytical of carcinogenicity studies on the carcinomas in a lifetime dietary feeding methods Available for analyzicg compound have been Inconclusive. The study with female rats using them 95 simazine in drinking water include the IARC has not evaluated the perccnt upper limit of tix multi-stage solvent extraction-gas chromatography carcinogenicity of simazine. Simazine model. The study used by CAG is more technique. has beon classified in EPAs Group D, recent and the CAG number gives a Humon Exposure. There are few data according to EPA's Proposed guidelines more conservative risk estimate. The on the levels of simazine In the U.S. food for Carcinogen Risk Aeneasment, based NAS and CAG risk estimates are shown supply. Six domestic food samples were 'ipon inadequate dsia from admsl in Table 13. analyzed for simazine in the FDA FY 77 studies. Point estimates 05 percent upper Ilmlt pesticides and metale program. None of Due to inadequate toxicolo~ydata, an entimates based on several models were these samples contained simazlne levels RhiCL and primary regulallon will not also calculated by the CAC, Using a In excesi of Qe quantltatlon llmite be proposed for simazine. The study lifetime exposure to 0.0 mg (between 10 and 100 pg/kg). used by the NAS to calculate an AD1

S-074999 01 tZ(~IZ-NOV-8~-t?:I4:1I) F4701 rev. 614-85 Federal Register 1 Vol. 60, No. 219 I Wednesday, November 13, 1985 I Proposed Rules 47013 has since been found to be invalid and X. Puhllc Docket EPA. Offlce of Drinking Water. Criteria and no new data are aveilsble to determine Standards Divlsion, Draft Occurrence/ en AADI. All ~upportlngmaterials pertinent to Exposure of Synthetic Orgiinlc Chemicals the development of this proposal are (Includlng peatlcldes) in Drinking Water. 6. Other SOCs Included in ihe Public Docket located at September 1984. Adlpates, dalapon, dibromomethane, EPA headquarters, Washington, DC. The Summaries of the analytical methor!s, dinoseb, dlquat, endothall, glyphosate, Public Docket is available to the public occurrence In drinking water and health hexachlorocyclopentadiene,PAHs, and the public should contact the effects in a single document have been phthalates, picloram, 1,1,2- Dlrnklng Water Regulations Docket prepared lo: each microbial trichloroethane and vydate were Manager for access. It would have been contaminant for which RMCLs are included in the list of SOCs under desirable to publish in this notice the list proposed. A typical reference listing consideration for Revised Regulations in of supporting materials, but ths Public would be as follows: the ANPRM. Data collection efforts on Docket is voluminus and a llstlng of the EPA. Offlce of Drlnklng Water. Crllerla and occurrence/human exposure and documents in this notice would be much Standard. r)ivision, "Anrilytical potential health effects have not yet too long. However, references on Methods. Occurrence. and Health Effects been completed on these substances and occurrence of chemicals In drinking of Total Coliforms In Drinking Water. these SOCs will be considered in later water, anelytlcal methods and health September 1884. phases of the Revieed Regulations. effects criteria document are cited Other pertinent references available IX. Impact of This Regulation below as these documents provide in the public docket include the summaries of dtlta used In determining following: The proposal of an RMCL is different the proposed RMCLs. Other materials in than proposal of an MCL in that an "Standard Methods for the Examinatlon of the Public Docket include such Water and Wastewater," 15th Edlllon. RMCL is, by law, to be based only on documents as the following: health and safety considerations, while American Public Health Assoclalion. Public comments on the ANPRM. Amer'cnn Water Works Assoclnllon. en MCL is to take costs into Water Pollution Control Federallon. 1975. Transcript of the December 13,1983, consideration. Therefore, this RMCL Annual Book of ASTM Standards. Part 31 proposal notlLe does not include an Public Meeting. Water, Amerlcan Soclety for Testlng and analysis of the economic Impacts of Reporl and background materials Materiale. 1916 Race Street. Philadelphia, vsrious possible RMCLs. However, the for the four public workshops, Fall 1983. Pennsylvania 19103. probable impacts of the various MCL Transcripts and minutes of NDWAC Bellar. T.A.. Lkhtenberg. 1.1. "The Determination of Halogenated Chemical alternatives will be analyzed and hleetings. reported at the time an MCL is Indicators of Industrial Contaminallon in Summaries of meetings, telephone Water by the Purge and Trap Method: proposed. calls from outside EPA. Method 502.2," U.S. EPA, EMSL *800/4- The report will include an analysis of Letters to/from public. 81459. the impacts of the various alternatives Bellar. T.A.. Llchtenberg, 1.1. "The Analysis of on the water supply industry vis-a-vis Technical Reports. Aromatic Chemicals in Water by the capital costs of technology, operating Other supporting materials. Purge and Trap Method Method 503.1." and maintenance costs and the For each inorganic and organic US. EPA. EMSL CPA eoO/441-457. feasibility of financing new treatments. chemical for which RMCLe are EPA. EMSL. "Methods for Chemical Analyeis Additionally impacts on the consumer proposed, a health effects criteria of Water and Wastes" (EPA soO/4-78- 020. March 1979). Available f.mm ORD and the nation as a whole will be document has been prepered md is Publications. CERI, EPA, Cincinnati, analyzed. available to ihe public. For example, a Ohlo 45288. Under the Regulatory Flexibility Act, 5 typical reference listing would be as National Academy of Sclences. "Drinklng U.S.C. 801 et seq., I certify that this follaws: Water and Health. Volume I(1977). I1 action will not have a significant impact (l980), 111 (l981),IV (1981). V (1983). EPA, Office of Drinking Water, Criteila and IARC. 1979. IARC Monographs on the on a substantial number of small Standards Division, Draft Health Effects entities. This proposed action will have evaluation of the carcinogenic risk of Criteria Document for Lead, September chemicale to humans: somt halogenated no economic impact because these are 1W. non-enforceable health goal& hydrocarbons. Vol. 20: 14-15. IARC. Approaches to Claeeifying Chemical Under Executive Order 12291, EPA Similarly, documents summarizing the occurrence of inorganic and organic Carcinogens According to Mechanism of must judge whether a regulation is Action, Technical Report No. 83/001. "major" and therefore subject to the chemicals in drinking water have been April 1983. requirements of a Regulatory Impact prepared for each chemical for which NCI. "Policy of Risk Assessment of the Analysis. This proposed action does not RMCLa are proposed. Individual Health Effects of Hazardous Exposures constitute a "major" regulatory action documents have been prepared for to Populations," Subcommittee on because it will not have a major inorganic chemicals whepas one Environmental Carcinogens. National financial or adverse impact on the document including all organic Cancer Advisory Board. 1983. Assessment of Microbiology and Turbidity community and it is a non-enforceable chemicals has been prepared. A typical Standards for Drinking Wiiter action. This regulation was submitted to reference listing for the inorganics (Workshop Proceedings).EPA. ODW. the Office of Managemeni and Budget occurrence document would be as 1983. for review as required by Executive follows: Evaluation of the Microbiology StRnderds for Order 12291. Drlnking Water. NTIS, Acceseion No. EPA, Ofnce of Drinking Water, Criteria and PD There are no paperwork burdens Standards Division, Draft Occumnce/ 297119. associated with this regu!atlan, and 49 Federal Register, 48294 (November 23. Exposure of Lead in Drinking Water, 1984). Proposed Culdellnes for there are no information collection Beptember 1984. WAS rcquirements subject to the provisions of Carcinogen Rlak Assessment. the Paperwork Reduction Act (144 The SOC occurrence document is The above health effects criteria 1J.s.C. 3601 el 889.). referenced as follows: documents and summary documents for

Sa74999 01 t3(07)(12-NOV-85-tl: t4:15) F4701 rev. 6-14-85 47014 Federal Regieter / Vol. 50, No. 219 1 Wednesday, November 13, 1985 / Proposed Rules iI tho microbials are available for viewing acceptable? Where data are not would be estimated to be without at EPA headquarters or in any of the ten available, is providing for an appreciable risk. EPA regional offices as listed in the assumed contribution of 20 percent Comment is requested on the use of beginning of the notice. Copies of these from drinking water appropriate? the terma "Drinking Water Equlvalent documents can be obtained for a fee at -Should RMCh for probable human Level" nr "Drinking Water ADI" to NTIS, US. Department of Commerce, carcinogens be set at zero? If replace AADI. 5285 Port Royal Road, Springfield, RMCLn are set at zero, what How should exposure to multiple Virginia 22161. The toll free telephone guidance, if any, should be provided contaminants in drinking wrlter be number is local 703/487- 800/338-4700: on the actually attainable target addressed to in the Revised 4050. levels in drinking water? Regulations? Because of concerns of XI. Request for Public Comment -For compounds with equivocal synergistic effects should a RMCL and evidence of carcinogenicity, should MCL be set for total SOCs or total IOCs? EPA requests public analysis, the RMCLs be set based upon Are the levels proposed for RMCLs comments and information on all AADIs, cancer risk levels or some for microbial contaminants appropriate? ospccta of this proposal. The questions other method? for which comment is being speclfically 1s the approach being proposd for solicited are listed below. Comment will The term "Acceptable Daily Intake" Giurdio and viruses which woil!d set be of greot assistance to EPA in or "ADI" has been criticized as RMCL and .MCLs, and monitoring but formulating a protective and practical connotating an "acceptable" level of also require a treatment technlqud approach to rcducing human exposure to exposure to which any level greater than regulation of filtration and disinfection conteminants in drinking water. the AD1 is "unacceptable". This is for surface waters and disinfection for Is the regdatory approach In this contrary to the views of most sclentiats ground waters appropriate? The public proposal appropriate under the SDWA, who generally interpret the AD1 as a water system would have a choice of Le.. set regulations for contaminante (1) "ballpark figure" which represents a meeting the MCLs vs. the treatment ! that pose a health risk to coiisumers in level of exposure which le not likely to technique requirement. What criteria drinking water, and (2) that have the result in adverse effects in humans. It is would be appropriate upon which to potential for occurring in drinking water viewed as a soft estimate in that base a variance from the treatment (e.g., pesticides registered for use in or exposures somewhat higher than the technique requirements for surface near drinking water supplies) or that aro AD1 are generally not expected to result water systems? for ground water known to occur on a regional or national in adverse effects; only if the AD1 is systems? basis but not necessarily at (a) high significantly exceeded would one expect such negative consequences. Should certain types of non- frequencies or (b) high levels. community systems, such as schools and This approach would result in a In order to help prevent misinterpretation, the term "ADI" could factories, be required to meet the MCLe comprehensive list of regulated that apply to community water systems? contaminants which would provide a be replaced with the term "reference standard by which to assess drinking dose". This term waa derived based Are the cited analytical methods I water when contamination is found. upon the process of generating the AD1 cited avcilable (i.e.. economically and Inherent in this approach is full public in which the NOAEL based upon animal technologically feasible) to ascertain the participation in the standard setting data is divided by an uncertainty factor level of those contaminants for which process. The alternate regulatory to generate a human dose. This derived RMCLs are proposed? approach which would set regulations human dose then serves as a point of A public hearing will be held at EPA for contaminants that pose a health risk reference, a benchmark against which in Washingtor., DC, on January 28 and in drinking water but only for those other human doses are compared. 29,1988, in Conference Room 1, adjacent f contaminants dctectcd et reletively high Comment is requested on the use of to the Washington Information Center frequencies at levels near the level of the term "Reference Dose" to replace for the interested public to comment and health concern. Health Advisories ADI. provide information and data on these would be providod as needed for those The term "Adjusted Acceptable proposed regulations. contaminants for which regulations EPA recognizes that many significant were not developed. Daily Intake" or "AADI" has been used to represent a total allowable exposure scientific and regulatory questions of the Do the proposed RMCLS represent as measured in mg/l drinking water, but Issue of the control of contaminants in a level such that "no known or drinking water. The Agency has anticipated adverse effect would result is derived directly from the AD1 which is measured in mg/kg body weight/day. attempted in this proposal to portray with an adequate margin of safety"? This modification of units of current scientific uncertainties in a -1s the three-category approach for measurement for a concept that is measured and objective manner. In this setting RMCb an acceptable traditionally expressed in mg/kg/day way, any data gaps or errom in logic method for factoring strength of has led to some confuslon and criticism, which may exist can be identified and evidence in the Rh4CL particulary from the toxicological corrected. Careful review of and determinations? community. It has been proposed that a thoughtful comment on the information -Are the classifications of the more appropriate tern be created, such chemicals scientifically acceptable? In this propose! and reference materials as "Drinking Water Equivalent Level la encouraged. -For non-carcinogens, is the approach (DWEL) or "Drinking Water ADI" and actual studies used for (DWADI). These terms would allow a Lists of Subjects in 40 CFR 141 computing the AADls scientifically shift to a medium-specific unit (mg/l I Chemicals, Intergovernmental acceptable? Are the safety factors drinking water) a?d define a relatives, Radiation protection, used In the AD1 calculcation for concentration in drinking water which, each contaminant sclentlflcelly Reporting end record keeping during the entire lifetlme of the human, requlremente, Water upp ply,

S-074999 01 I~O7~12-NOV-8~-l7:14:1(1) F4701 rev, &14-85 f c" Federal Register / Vol. SO, No. 210 1 Wedneeday, November 13, 1985 1 Propoeed Rulea 47015

Dated: October 10, ~8~s. roposal (Le., primarily occurrence, independent scientific peer review and bs Thomar, ealth effects, and analytical methods) for the SDWA to be amended to Administmtor. receivedR on the ANPRM for revised formalize the health advisory process. Appendlx A4ummary of Publlc drinking water regulations. Comments (2) For which contaminants should Comments Pertinent to the Proposed on such items as monitoring and GAT regulations be sei? Into which category Recommended Meximum Conlambant are pertinent to MCLs and will be should the contaminants be included: Levels (RMCLS) for Organic, Inorganic summarized In the MCL proposal. Tier I, Tier I1 or Tier 111 as described? and Mlcmblal Contaminants In DrlnkIng (1) Is the tbree-tiered approach What levels for the RMCLs would be Water appropriate? What criteria should be appropria le? used to determine which contaminants The majority of written comments The following is a summary and should be In each category? received addressed which contaminante dlscussion of the principal public Thlrty-four comments addressed this should regulations be set, sprcifically comments to EPA's proposed rule for the issue. The majority of commentere MCLs. The comments received did not establishment of RMCLe for oganlc, favored the three-tiered approach distinguish between RMCLs and MCLs, Inorganic, and microbial contaminants because this le a sound regulatory however, it is appropriate to discuss lor In drinking water. EPA specifically approach which offers Stales monitoring which contaminants should regulstions solicited comments on the followlng flexibility and permits States to optimize be set for oven though tho comments issues In its October 6,1983, Advance available resources. Most of these portain to MCLs, not RMCLe. Notice of Proposed Rulemaking commentere agreed with the criteria for Concemlng occurrence date, five (ANPRM): each category, as stated in the ANPRM. commenters felt EPA should broaden its 1. Is the three-tiered approach A few commenters su gested some data base. A single, large scale survey to appropriate? What criteria should be recommendations to If is approach. as determine the occurrence of the various used to detennlne which contaminants outllned in the ANPRM, which included: constituents was suggested. Occurrence should be In each category? retain the distinction between studies should be broadened to include 2. For which contaminants should community and non-community water stelistically valid, geographically regulations be set? Into which category supplies; randomized sample of every system should the contaminants be included: additional categories should be size, including ground and surface water Category I, Category 11, of Category 111 added in the future, if necessary; sources. It was also propolled that EPA as described? What levels for the Category I should read, "have an adopt a chemical data reporting system RMCLB would be appropriate? adverse effect," not ".my have an 3. Should a treatment technique adverse effect"; for all substances identified under other requirement of disinfection be set for all monitoring frequency for Category PEA programs. EPA should then provide ground wa!.r systems? Should a 11 chemicals should be established by this information to the primacy agencies. treatmmt tectnique requirement of the State using guidelines set by EPA Sixteen comments addressed the tier filtration be set for surface water monitoring should be based on in which the contaminunts should be systems? geographical areas within a State, type included: Tler I, Tier I1 or Tier 111. The 4. Is using the AD1 an appropriate and source of supply, historical data, major!ty of commenters felt that the method for establishing RMCLe €or non- and system size; and turbidity and total coliform standards carcinogens? a national monitoring program should be in Tier I to protect against 5. What safety factors should be used should be cerried out before waterborne disease. The inorganic in conjunction with chronic toxicity data categorizing thc chemicals. chemicals currently regulated by EPA in setting RMCLs for non-carcinodens? A few commenters did not favor the were placed predominantly in Tier 11 to 0. What approach shovld be used to three-tiered approach. One commenter allow for monitoring flexibility. but a set RMCLo for carcinogeni? felt "the concept is needlessly few commenters recommended deleting 7. Is waiving certain MCLJ when complicated and may result tn a lengthy, a tew of the MCLs and developing susceptible populatione are nc! affected unreasonable, and superfluous debate health advisorielc instead (Tier 111). The an ap ropriate approach? over which category a chemical should several contaminants listed in the 0. Stould separate or dlf'erent MCLs be in." They suggested only two ANPRM that were already Included in be considered for certain son:aminants categories-MCL or no MCL Their the secondary drinking water for non-community water eystems? reasoning was that primacy agencies regulations were all placed in Tier 111 9. Are analytical methods available could adjust monitoring requirements, along with several other inorganic for contaminnnts under consideration? Furthermore, they recommended EPA chemicals. A few commentere felt that EPA received 133 wri!len commcnts put a time limit on the applicability of the synthetic organic chemicals should during the w)+ day public comment health advisories so they will either be either be in Tier I1 or Ill, depending on period and three statements were updated, establish a MCL if necessary occurrence and adverse health effects presented at the public meeting held in or wlthdrew the health advisory and information. The distribution of Washington, D.C.. on December 13,1983. provide reasons for doing so. Some of chemicals for Tier I, 11 and 111 was as The statements preiented at the public the other commenters who did not favor follows: meeting have been incorporated with this approach were also concerned the written comments submitted. These about the health advisory program but 135 comments included 02 industries for different reasons. They felt that the and industry associations, 33 water health advisories were being misused by utilities, 11 state governments and state other EPA program offices and they go organizations, 0 public interest groups, 4 beyond the statutory authority of the private citizens and 11 from other Safe Drinking Water Act (SDWA), groups including some federal which does not provide for a program of government agencies. quasi-regulatory guidance to state and. The following discuselon summarizes local officiale, Their recornmendations comments pertinent to the RMCL were for health advisories to receive

W74999 0115(07XI2-NOV-85-17:14:21~ F47M rev. 614-85 47016 Federal Register / Vol, 60, No, 218 / Wednesday, Novembor 13, 1986 / Proposed Rules

nu ere eigniflcantly dlfferent for adults or commenter stated that "chlormation will CMur I II 111 children". They also questioned uslng oxldize Cr(II1) to Cr(V1) since it is the - the new-born rat as a model for thermodynamically favored speciee ...... children. Furthermore, they felt that the under oxidative conditions in solution". possible role of barium and A few commenters feit there should cardlovascular disease may not be be no change to the present MCL for supported since they are based on chromium since Cr(Il1) oxidize# to ...... Intravenous studies. Cr(V1) and no easy procedure exlsls lo ...... Six commenters felt that the standard analyze the two species separately. should remain the samo, whereas, two commentera felt the standard should be Two commenters felt that the ...... deleted. No reasons were stated for chromium standard should be deleted either position. altcgclher. No reasons were stated...... Cadmlum Lead ...... Twelve commentere addreneed the Twenty-one comments addressed the 1 present cadmlum MCL of 0.010 mg/l. present MCL for lead of 0.05 mg/I. The 'I1 al 111. The majority of commenters felt the majority of commentere felt the present In order to prasent a summary of the MCL ohould remaln the same. One MCL should remaln the same since thin commentn which addressed which commenter mentioned leaching of level protects the health of chlldren and contemlnants should regulations be set, cadmium due to corrosion of galvanized adults. They felt the MCL should not be the discussion will be summarized per pipe as the mode of exposure In drinking lownred because the belief that even chemlcal. water. Two estimates of the relative very low levels of lead in the blood have source contrlbutlon of cadmium from adverse effects on children is erroneous. Inoganic~ drinking water were 10 percent and 6.1 Most of these commentere agree with Arsenic percent. One commenter felt the MCL EPA'n statement In the ANPRM that, should be ralsed but did not specify a "while lead in drinking water may be Eleven commentere eddressed the level. the result of contamintition of the water present arsenic MCL of 0.05 mg/l. The Chromium source, it most frequently reeults from majority of commenters felt the corrosion in the distribution system". standsrd should romain the same Twenty-two comments addressed the They favored reducing lead levels by because it appears that both valences present MCL for total chromium of 0.05 implementing corrosion control are toxlc and there is no available mg/l. Some commentere submitted programs such as special monltoting anslytical method to dlfierentiate. detailed scientific information on activlties where corrosion in copper, Howevcr, three commentere fclt that chromium which has been considered due to differing toxicities, seperate galvanized and lead plping is suspected by EPA. The majority of commentere felt of being a problem. Furthermore, they MCLs for trivalent and pentavalent the MCI, should be changed either by arsenic should be established, If an suggested that regulatlons for corrosion establishing a separate MCL for control should be determined by the acceptable means of analysis is trivalent (Cr 111) and hexavalent availoble to differentiate the two chromium (Cr VI] or establishing an primary agency based on local compounds. MCL for only hexavalent chromium. conditions. A study In Carroll County, Two commentere felt the MCL should Their reasoning was that the two Maryland, found the current MCL was be deleted and EPA should prepare a valence states can be distinguished exceeded 24 percent of the time. Health Advisory. Their reasoning is that analytically and an MCL for Cr(VI] is Most of the plumbing In this study studies have been done in their cities warranted based on Its toxicity while was copper with lead soldered joints. because they have levels of areenlc In Cr(II1) is noq-toxlc and considered an One commenter noted that cigarettes their drinking water above the MCL The essential nutrient. This positioli follows ar.d alcohol consumption were results of these studies have shown no NAS' recommendation In Drinkins Important sources of lead expoeure: e ill-effects from ingesting these arsenic Water nnd Health, Vol. IV. Two percent due to cigarettes, 8 percent due levels over many years. commenters suggeeted screenlng !or to alcohol, 6 percent due to drinking total chromium and when this exceeds water, and 77 percent due to other Barium the numerical standard, analyzlnl( for Influences. Twenty-five commentere addressed hexavalent chromlum to determine A number of commentera felt the lead the present barium MCL of 1.0 mgll. One whether the water meets the standard. standard should he lowered since "lead commenter submitted detailed scientific These commentere further stated that is bioaccumulative and the health information on barium, which has been total chromium In drinking water is no: effects of lead, particularly on the considered by EPA. The majority of of significant concern. Reasons for this central nervous system Is irreversible". commentere felt the barium MCL should opinion included: (1) Chromium is Most of these commentere agreed with be raieed to 4.7 mg/l, which is the level . extremely insoluble and immobile in the NAS' recommendrition that the MCL the Naiional Academy of Sciences natural environment, (2) it le rarely should be lowered to 0.025 mg/l. One recommended in Drinking Waferand found at concentrations above 0.05 nq/l, comme7ter felt the RMCL should be Health, Vol. 4. These commentere (3) only the trlvalent form occurs in zero because lead le non-essential end supported thls position because an natural waters slnce the hexavalent any amount is undesirable and probably absorption factor of u)percent was form is quick1 reduced, and (4) traces harmful and the MCL should be 0.002 used, even though conservatlq:e, rather of Cr(V1) wourd be quickly converted to mg/l. Another commenter suggested the than w) percent which was ueed for the Cr(lI1) due to the acidic nature of the RMCL should be 0.01 mg/l in order to present MCL These commentere felt stomach. Most of these commentern felt protect the young and developing that, "there le no evidence in humans that Cr(II1) does not oxldize to Cr(V1) nervous systems of infants and young that gaslrointestlnal absorption rates during chlorinatlon. However, one children.

S-074999 01 16(07)(I2-NOV-I5- 17: 1425) I F4701 WV. 6-14-85 Federal Redder / Vol. 60, 218 / Wednesday, November 13, 1085 / Proposed Rules 47017 No. --- Conversely, one commenter felt the Silver treatment of drinking water". Theso MCL should be raised. No reasons were commenters stressed that aluminum stated. Eighteen comments addressed the silver MCL of 0.05 mg/l. Some salts used in water treatment are the Mercury commentere submitted detailed most common source of this metal in drinking water. Eleven comments addressed the scientific Information on silver, which present MCL for mercury of 0.002 mg/l. has been considered by EPA. The Conversely. a few commenters felt The majority of commentere felt the maJority of commenters felt the MCL that an MCL was jiistified based on the standard should remain the same and should be deleted because of minimal adverse health effects. One commenter reco.nmended analytical methods be occurrence and because of the lack of suggested adopting the WI 10 guideline developed to differenti~tebetween adverse health effects. A few of 0.2 mg/l. commentere stated that silver does not organic and inorganic mercury. Antimony Conversely, two commentere felt the occur at elevated levels In drinking standard should be deleted. No reasons water as a result of photographic Fourteen comments addressed the were given. discharges. Furthermore. "silver is possibility of establlshing an MCL for rapidly and almost completely antimony. All of the commentere felt Nitrate incorporated Into sludge during that an MCL was not warranted based Fifteen comments addreesed the secondary wastewater treatment". Some on luck of occurrence and adverse present nltrate-nitrogen MCL of 10 mg/l. of these commentere feel that argyria is health effects. A fcw commentere not an adverse health effect but a The majority of commenters felt the rocommended developing B health MCL should romain the same since it is cosmetic effect. Onc commenter cited advisory for antimony (Tier 111). a reasonable standard especially the MCL reasoning as, "the need to set a concerning the flexibility afforded for standard for silver arises from its Asbestos non-community systems. A few othor intentional addition to rater as a commentere felt that the same provision disinfectant. The chief effect of silver in Twelve commentere addreseed the which applies to non-community water the body is cosmetic". They supported possibility of establlshlng an MCL for systems should also apply to community NAS' recommendation in Drinking asbestos. All of the comnienters felt that water systems since "water related Water and Health, Vol. 1 to delete the an MCL is not justified. One commenter cases of methemoglobinemia that have MCL due to limited occurrence. Some observed that all but a mall percentage been reported, have seldom if ever commentere suggested preparing a of U.S. drinking water contains asbestos involved community public water health advisory for silver. concentrations below on million fibers systems". Two commenters questioned Five commenters felt there should bo per liter. This exposure is due to natural the nitrate standard because there is no change to the silver MCL They felt it erosion. This coinmenter stated that little information available to support should be in Tier I1 allowing the States exposure to asbestos in food and air is either retaining or revislng the present flexibility in monitoring due to eilver's eAtimated to be 1,W to 1O.OOo times that MCL They recommended that, "primacy infrequent occurrence. due to drinking water. Thz above commentere felt tha! there is no agencies have more flexibility in Aluminum resolving problems where infants are evidence available to demonstrate a likely to consume the water". Another Twenty-two commenters addressed health risk from ingested asbestos. One commenter stated that nitrate the pnsslbility of establishing a MCL for commenter stated that "if there is a contamination can be minimized by aluminum. Three commmters submitted causal relationship between asbegtoti in modifying the well construction, as detailed scientific information on drirking water and cancer, it is stated in the ANPRM. This information aluminum, which has been considered extremely weak". Two commentere should be disseminated to the consumer. by EPA. The majority of commenters felt stated, "if additional research One commenter believed that the aluminum does not warrant an MCL demonstrates an adverse health effect MCL should be raised to 20 mg/l because drinking water is not a from Ingested Rsbestos, control can be because nitrate is expensive and significant source of aluminum exposure provided by requiring properly designed difficult to remove. They recommended and there are no clearly demonstrated and operated filtration planls for surface using premixed formula or bottled water adverse health effects for the general population. of these commenters water supplies and distribution of non- end issuing advisories to local Most corrosive water". A number of these physicians, health departments and felt aluminum should be in Tier I11 so as to protect the sensitive subpopulation of commenters felt asbestos should be in hospitals, in order to protect childron Tier 111. and pregnant women. dialysis patients. However. one commenter stated, "normal dietary Beryllium Selenium sources of aluminum are an unlikely Eighteen comments addreseed the source of concern relative lo the Six commenters addressed the present MCL for selenium of 0.01 mg/l. dementia cited in the ANPRM". Another possibility of establishing an MCL for The majority of commentere felt either conmenter suggested reporting beryllium and they all agreed that an the MCL should be raised or deleted. requirements similar to sodium, on an MCL is not warranted. One corn nenter Their reasoning was that selenium has annual basis to local health officials to stated that there is no evidence that anticarcinogenic potential and ths afford protection to dlalysis patients. ingested beryllium poses a human scientific basis for the present MCL Two commenters felt that regulations cancer risk nor any other adverse health appears at best questionable. Also, there under the SDWA are not an appropriate effects. Furthermore, beryllium is is no economical way for small systems vehicle to deal with senile dementia and present in natural surface waters at ' to remove selenlum at present MCL dlalysis encephalopthy. A number ot concentrations generally leus than 1.0 levels. Conversely, a number of commenters raised the point thal. "any pg/l with average concentrations of commentere felt the MCL should remain limitations placed on alumlnum in . generally less than 0.2 pg/L Beryllium is the same and placed in Tier 11 to allow drlnking water should recognlze the relatively lnaoluble and le rapidly for rnonitorlw flexlblllty. Importance of the use of alum In the absorbed by clays.

S-074999 0 I I7(07K 12-NOV- 85- 17: 14:2L) F4701 rev. 6-14-65 47018 Federal Register / Vol. 60, No, 219 / Wedneday, November 13, 1985 / Proposed Rules

. Copper that EPA do research on the role of Synthetic Organic Chemicals (SOCs) Fifteen comments addressed the chloride and hypertension. Some Twenty-two comments addressed the possibility of establishing an MCL for treatmentr add sodium to drinking issue as to whether or not to establlsh copper. The majority of commenten felt water, such as soda ash addition and RMCh for synthetic o~ganicchemicals. an MCL is not warranted and copper ion exchange softening. The majority of comments dealt should remain as a secondary Sulfater generally with synthetic nrganic regulation. A few of these commsntem chemicals. not specific chemicals. Most recommended copper be placed in Tier Pourtuen comments addrosaed the of the commenters felt that regulations 111. Conversely, one commenter felt an possibility of establlshlng an MCL for should be set for SOCs and put In Tier I1 MCL should be established because sulfates. Presently, there is a secondary so primacy agencim would have there is evldence of adverse health maximum contaminant level of 250 mg/l, monitoring flexibility to account for effects from exposure to elevated levels All of the commentera recommended wide varialiona of occurrencn. Other in a public water supply system in their that an MCL was not warranted and commenters recommended developing State. should remain as a secondary regulation health advisories (Tier Ill) until Cyanide since the sole attributable adverse sufficient occurrence and health effccts health effect is BU s laxative. Two data are availabls. One commenter Elght comments addressed the noted that the only pesticides likely to possibllity of eslablishlng an MCL for commenters noted that elevated levels of sulfate are not uncommon. Levels as intrude into ground wnter are highly cyanide in a eneral fashlon. All of the polar, weter-soluble, soil-incorporated commcnlem felt that a MCL was not high as 2,000 to 3,000 mg/l have been required but recommended a health reported. However, one commentsr compounds such as aldicarb, and advisory be set (Tier 111). stated that "EPA's 1976 Interstate Water conditions can be evolved to limlt thelr Carrier Analysis found thnt even the leaching. A fcw commentera suggested Molybdenum highest concentretion of sulfate detected that a random, nationwide survey Thirteen comments addressed the was below the level at wliich adverse nhould be conducted cnd funded by EPA posalbility of establlshing an MCL for health effects occur; 88 percent less to determine the frequency of molybdenum. All of the commentere felt than, 250 mg/l". This commenter occurrence and concentration levels to an MCL was not justified due to lack oi supported NAS' contention that there see whether a contarninant is placed in adverse health effects. One commenter Tier 11 or 111. Another commenter noted are no observable adverse health effxis that, "the availability of health stated that a failure in the ANPRM was et 500 mg/l. the omission of discussing the question advisories, in the absence of a drinking of molybdenum deficiency perticulorly Thallium water standard help present a more accurate picture of the health issues to as it relates to cancer. This commenter Five comments addressed the explained the limitation of NAS' the public, however, in many cases, the possibility of establiehlng an MCL for absence of a drinking water staiidard adequate and safe intakes, that I! is a thallium in a general fashion. All of the range, not a specific limit. A few of the may actually result in the installation of above commenten recommended commenters felt that an MCL was not treatment facillties for levels of molybdenum for Tier 111. warranted: no reaso-is vwe elated. contamination which actually do not Vanadium exceed the Health Advisory level. Were Nickel formal MCLn established, it is unlikely Thirteen comments addressed the Twelve comments addressed the that removal would occur unless the possibility of establishing an MCL for possibility of establinhiilg an MCL for MCL were exceeded". In regard to the nickel. All of the commentare stated that vanadium. They all felt that an MCL six pestlcldes currently regulated by an MCL is not warranted since there are was not justified and that n hedth EPA, one commenter stated that, "there no adverse health effects and nickel in advisory should be developcd (Tier Ill). are virtu.illy no cases of non- drinking water contrlbutca a very small One commenter stated that vanadium is compliance". portion of the daily Intake. One "poorly absorbed when ingestzd and PAHs commenter stoted that it is seldom there IR a lack of e4dence of any observed In fresh water. chronic oral toxicity", Two commentere spPcifically addressed PAHs.One commenter stated Sodium Zinc that "the control of PAHs could best be Eighteen comments addressed the Seventeen comments addressed the implemented by limiting or possibility of establishing an MCL for possibllity of establishing an MCL for discontinuing the use of coal-tar sodium. Presently, there are monitoring products in water distribution and and reporting requirements for sodium zinc. Presently, there is a secondary storage systems. The other commenter to protect the sennitive subpopulation on maximum contaminant level of 6 rng/l. recommended PAHs for either Tier I1 or sodium restricted diets. All of the All of the commenters felt an MCL for Ill due to their widespread use in the commenten etated that an MCL is not zinc was not warranted. Most of the water supply industry and their high required by recommended developing a above commentere suggeeted developin8 toxicity. health advisory [Pier 111). These a health advisory (Tier Ill) and/or commenters stated that food is the maintaining the secondary drinking Acrylamlde major source of sodium, not drinking water regulation. One conmenter stated Two commenter:. felt it was water. One commenter noted that that there le no evidence of chronic zinc inappropriate to establish an MCL for drinking water sodlurn levels seldom toxlcity and acute symptoms do not ecrylamide, One of the two commentem exceed 200 mg/l. Another cummenter apparently occur in water at levels less want the phrase in the ANPRM of "total recommended that po'nt-of-use than 40 mg/l. Another commentar noted acrylamide" to be replaced with treatment devices are the most practical, :hat "at levels well below toxicity, it "acrylamide monomer". They offective and economtcsl means for would cause taste problems making the recommended that EPA delay removlng sodium. They also euggested water unflt to drink". estahllshlng an Rh4CL for acrylamide

-74999 01 I8(07)(12-NOV-85-17: 1432) F4701 rev. 6-14-85 Federal Regirter / Vol. 50, No, 219 / Wednesday, November 13, WRS / Proposed Rules 47019 I until they complete an oncogenicity/ Board, "no adverse health effects are Turbidity chronic toxicity study. Another likely in humans at current exposures". Twenty-two comments addressed the commenter stated that "residual Micm bioln turbidity MCL 01 1 turbidity unit [TU) acrylarnide is regulated by FDA and If (up to 5 TU). All of the commenlers this standard does not protect public Total Coliforms supported inclubion of turbidity in the health, then the FDA standard should be The MCL for total coliforms of 500 CFU/ml hean considered by EPA. there is not enough data to support this should cause the water to be non- Phthalate Estan test for ita une either in conjunctlon potable and require treatmcnt, with, or as a substitute for existing In one public water system a good Two commentere did not support an procedures. correlation exists iietween SPC and MCL for phthalate estere because of Another argument for simplifyinp the chlorine residuale. In areas with low to limited occurrence and Insufficient prescnt coliforms MCL came from cmall non-ex!o!ent chlorine residuals. high toxicit, to warrant regulation. Also, water supply systems who said thu SPCs are seen although no coliforms are phthalates are bio-degradable in water. "monthly averages ara not only present. The reverse is true in areas Alachlor complicated but meaningless fc i small with sufficient residual-no coliforms systems. The significance 8,; the exact and low SPC, and One commenter did not favor number of bacteria is :lot understood'. Interference of total coliform establishing an MCL for alachor because Most of the commnten felt that a analysis. occurrence in drinking water Is low. "check" sample is imperative when a positive coliform iiample occurs. A Giardia Xylenes number of these r.ommentere Eighteen comments addressed the One commenter did not support an recommended th it "check" sample possibility of establishing an MCL for MCL for xylene. No reasons wmgiven. results should be included in calculating Ciwdio. The majority of commenters did ni! favor establishing an MCL Toluene compliance, unlike the current practice. In addition, E few commentere because the analytical methodology is Two commentere felt that an MCL su ested measuring only for fecal not economically or techically feasible. wae not warranted for toluene becawe coP iforms, not total coliforms since It In addition, a few of these commenters according to WASHealth Assessment would better reflect the conditions of the felt Cicrrdio does not constitute a Document and the Science Advisory water system. significant threat to the general

Sa74999 01 19(07XI 2-NOV-US- 17: 1433) F4701 rev. 61445 47020 Federal Register / Vol. 50, No, 210 / Wednesday, November 13, 1085 / Proposed Rulerl population. One of the above considerably resistant to chlorination requirements where monitoring commenters stated, "efforts should be and an MCL would ust impose heavy techniques are not practical or made to develop improved testing costs with essential Iy no benefits. One availab!e, ouch as Cmdja, which can be procedures for C;udiu; if so, then an State noted that they have had several removed by filtration followed by MCL for Giurdiu should be established". Legionella outbreaks which have beeq disinfection". This commenter also Some of the commentem who did not due to an appurtenance in internal supported mandatory dieinfection lor all favor a drinking water standard for plumblng; therefore, control should be public water systems, as a Tier I Giardia mentioned that filtration directed to appurtenances rather than standard to afford protection against (1) followed by dlsinfuction la effectlva through drinking water standards. unexpected changes In raw water against Giardia Howeverl they opposed (3) Should a treatment techniclie quallly, (2) introduction of mandatory filtration ds the only requirement of disinfection be set IC- all contamination in the distribution alter:iative to pratect against Ciudia. ground water systems? system, and (3) viruses and Legionella but recommended source control (e.gs1 Twenty-two comments addressed the which can pass filtration. beaver removal). One commenter possibility of establishin a treatment The minority opinion who did not further stated that "filler treatment is technique requirement of disinfection for favor mandatory filtration for all surface neither the chuapert nor the most all ground water systems. The majority water sytems felt this was a State effective means of control of Giudiu of commentera opposed mundatory discretion issue and recommended that cysts in drinking water supplies for a disinfection of ground water systems. it was more approprie!a to establish and required tmatment method for They &It that mandatory disinfection is enforce proper MCLs to insure the Giardiasls control". a State discretion issue. Furthermore, microbiological quality of drinklng Conversely, two commenters felt trn these commenters recommend physical water and then vary monitoring in MCL should be established even though protection of the source, periodic accordance with the type of source and Giurdiu is difticult to enumerate but sanitary surveys and good well isolation treatment provided. Furthermore, most rather oasy on a preaence/absence and construction. Most of the above of these commentere were against basis. One commenter stated that, "26% commcnters urged EPA to focus its mandatory filtration as the only of the cases of waterborne dlssase efforts on bacterial standards and not alternative to protect against Giudiu. reported between 19814 were due to on treatment techniques. One They recommended source control and Giurdio". Another commenter felt that commenter felt that properly sited and periodic sanitary surveys. One Giurdiu should be monitored on a constructed ground water systems commenter also recommended monthly basis for all untreated or which are regularly monitored for "disinfection of surface water supplies disinfected only water nupplles. collforms will not pose a significant and an aggressive monitoring program in Furthermore. "when an analytical added health risk. One State who the watershed and distribution system," method is available, then an MCL of 0 strongly opposed mandatory which is consistent with the cysts should be established for finishod disinfection stated that, "it is politically Microbiology Workshop conclusion, "all water regardless of treatment". difficult to accomplish the installation of surface water sources should be The issue of mandatory filtration will chlorinatbn equipment on all ground pretreated by such processes as be further discussed later in this section. water supplies with even further coagulation, sedimentation and filtration Viruses difficulties anticipated in continuing the treutment once started'. or their equivalent prior to disinfection, Nineteen comments addreseed the Conversely, some commentern unless it can be shown on the basis of a possibility of establishing an MCL for favcred mandatory disinfection for all sanitary survey that such treatment is viruses. All of the commentem did not ground water systems. Hor,ever, a few not necessary". Another commenter favor an MCL for virusee because of these commenters fe:t that States elated that "the establishment of analytical methods are not available should be allowed the flexibllity to treatment standards other than which are timely and cost-effective. waive for systems based on periodic disinfection is not justified when there They felt more research was needed In sanitary surveys and good well are means available to determine water this area. hoper disinfection should be construction. quality". emphasized but these commentere did Should a treatment technique (4) Is using the AD1 an appropriate not recommend mandatory disinfection. requirement of filtration be set for method for estbblishing RMCL for non- carcinogens? Legionella surface water systems? Nineteen comments addressed the Five comments addressed this issue of Eighteen comments addressed the possibility of establishint( a treatment the AD1 approach for non-carcinogens. possibility of establishing an MCL for technique requirement of filtration for All of the commentera felt that the AD1 Lcgionellu. Every commenter felt that an surface water systems. The majority of approach was quite valuable and MCL was not warranted since the commentere favored mandatory appropriate. Two commentem relationship beween Legionellu and filtration for surface water syetems to empi:asized that the contribution of public water systems has not been insure the microbiological quality of the drinkit:g water to the total exposure established, One commenter noted that, drinking water. One commenter felt , should be considered. "an MCL for Legionellu is not wamant?d filtration should be a Tier 11 standard, (6) What safety factore should be used because it is a problem that originates with the provision that variances would in conjunction wlth chronic toxicity data with a user's substandard operation of a be allowed if suitable monitoringarid in setting RMCb for non-carcinogens? hot water system". Another commenter watershed characteristics could Four commenters addressed the issue further stated that, the best defense is demonstrate no health risk. A few of of safety factore for non-carcinogens. education of homeownem and building these commentern mentioned that The commentem recommendatIons were supcrvisors". In addition, another mandatory filtration seems prudent varied. Two commentere suggested that commenter felt that an MCL was not particularly in light of the growing EPA use a range of factors so that the warranted because the primary route of concern over infectious agents, such as exact magnitude of uncertainty depends infection is via the respiratory system, Ciardiu. One commenter further stated on consideration such as the species and not enteric. Lsgionella is that "the SDWA provides for treatment teated, and the quality and quantity of

-74999 01 20(07)(12-NOV-8J- I71438) F4701 rev. 6-14-85 Federal Register I Vol. M), No. 219 I Wednuedey, November 13, 1985 / Proposed Rules L;\ 47021

the tiA data. Another commenter stated be considered "sufficlent" evidence of InorZpanic Chemicals that 'II. aafety factor of 100 should be carclnogenicity before they can be used to account for diffeting sensltlvlties considered for use in human cancer risk. Asbestos within the heterogeneous population They suggested uslng IARC's One commenter noted that the only (c :.' voung VI. old): variability in body classification scheme which states that available analytical method for asbestos weillhte and the amount of water "llmlted~evldence In anlmals la In water, transmlsaion electron Ingested dally; and uncertanties in "inadequate" to evaluate the microscopy, is very expensive ($300- ekirepolatlon". Anotlrcr commenter felt, carcinogenicity in humans. $800 per sample). This method is neither "NAS" safety factors are appropriate (7) la walving certain MCLe when precise nor accurate enough to use for only when epldemlolglcal date are susceptible populations are not affected enforcement purposes. lacking. If historical data are available an appropriate approach? to allow a lower aafety factor (e.g,, NQ) Five comments addressed the issue Chromium or wher P a benefit can be prescribed whether to waiver certain MCLs when One commenter noted that there are (e.g., Iluorido) then a lower safety factor susceptible populallons are not affected. two methods lo separate dissolved Cr should be applied". The commentere were split on thls lssuc, (111) from Cr [IV).The first was (e) Whet approach should be used to three felt this was an appropriate developed by Martin and Riley at U.S. set RMCb for carcino ens? approach, partlculerly concerning EPA, Environmental Monitoring and Eight commenlers a t! dressed how nitrate. Support Laboratory (EMSL). The RMCLe should be set for carcinogens. Two commenters did not favor this colorimetric method (Sfandord Mefhods, Four commenters felt that settinR 16th ed. W12.8) is also valuable for RMCLe et zero for iron-threshold approach. One commenter stated that. carcinogens was appropriate, however "waivers batted on population would be dietinguishing the hexavalent form. They RMCLe must be clearly defined as a very subjective and lead to the setting of also mentioned that Krull, Panaro arid health goal. A common sentiment among undersirable precedents. Gathering the Cersmar (j.Chrum. Science. In press. some of these commanters was tl.at zero data to make determinations for a 1983) have developed a method for provides little foundatlon for the 'suscrptible poptilation' would be too speciation of Cr (VI)and Cr (Ill) in estaLlishment of MCLe. Furlhermore, timely and costly and populations are water using HPLC-nirect Coupled these commenters felt that RMCLs serve tco mobile. Furthermore, failing to Plasma Emission Spectroscopy. no purpose and are impractical because account for synergistic effects from Another commenter recommended they are confusing to the public and the other exposures would make any waiver that the Atomic Absorption method be press, if not the regulated community. meaningless in terms of protecting uoed to screen for total chromium, but Deeplte the shortcomings of RMCLs, a public health". that Cr (VI]should be the basis for the few commentem made (8)Should separate or different MCLs MCL recommendations on how to improve be consldered for certain contaminants Pesticides the understanding of KMCLe. One for non-community water systems? commenler recommended that EPA, Two commenters addressed this issue. One commenter noted the analytical States and the American Water Works One commenter favored tho existing method for glypnosate in water requires Associstion develop educational procedures for non-community water a high degree of technical skill and is material to explain the differences systems to comply with the MCLs for very expensive. Cc its are about W per between RMCLe and MCLe. Another coliforms, turbidity and nitrakes. The sample. National cdst for each public commenter suggested that RMCLR and other commenter recommended water system to monitor two times per MCLa should be proposed and "changing the definitions for community year would approach $100 million. promul ated simultansoualy. and non-community to more properly Another commenter noted that while Anot\er s*iggestionas to how RMCb reflect the difference between transient electron capture cletection has excellent should be set for carcinogens was and non-transient populations because characteristics for insecticides and expressed by one commenter to, the current approach of resident vs. non- herbicides regulated by the SDWA. it "evaluate each compound and based on resident does not properly protect the has generally ?oor detection ability for strength of the scientific data and health of persons using dr!nking water the currently used phosphorous and comparative carcinogenicity of each from syrctems such as schools and nitrogen containing pesticides. Specific compound, establish an RMCL at a level factories which are non-communlty detectors are required such as, determined to have a mininal or systems that may have excessive thermionic detectlon to detect even ).' 41 lnslgnlficant health risk. These rlak concentrations of other contaminants, levels of atrazine, simazine and tabutos. levels should be consistent with pest such as lead. Community systems determinations of "acceptable" risks to should apply to non-transient PART 1¶l--IAMENDEDI society, possibly 10-8". populations such as schoc!s, day-care For the reasons set out in the Two commenters were opposed to facilities, and factories not just preamble, it is proposed that the using risk models because there are residential. Non-community systems following be added to proposed Subpart such a variety of models which argue nhould apply to true transient F. Pcrt 141, Subchapter D, Chapter I of against the selection of only one for risk populations such as hotels, Tltle 40. Code ofFedem/ RegUhth18as .assessments. One commenter auggestcd campgrounds, gas stations, restaurants, proposed on May 14.1985 (50 FR 20175). EPA should consider a comblnatlon of etc". 1. The authority section of Part 141 mathematical models and the safety (9) Which analytical method6 are continues to road as follows: factor approach. Another comyenter most reliable? said, "due to the inadequacies In today's Only a few comments were received Authority: 42 U.S.C. 3-1.3Mg-3, scicnce, EPA should stale that they are whlch addressed the availability of jool4, and 300)-8. unable to determine safe levels for analytlcal methods for contaminants 2. It is proposed that Subpart F, 40 carcinogens". under consideration. The following 9 141,M) is amended by adding (a) (e] One commenter recommended that CFR discussion will be eutnmarlzed per through (16) and (b) table entries (4) anlmal bloeeeay reeults would have to chemlcal. through (18) to read as follows:

S-074999 012 t(O7X 12-NOV-8J- 17: 14:42) F4701 rev. 0-14-85 47022 Federal Regleter / Vol. 60, No. 219 / Wednesday, November l;r, 1985 / Ropoeed Rule6 ‘I #141.60 R.comnrmd.dmuhnum conbmlnrnt hvalr lor mk M R?y mtrvnlnmta (a). (1 1) undw ...... 0.0002 (8)o*m*m (low)...... 0.11 . (12) ...... 0.34 ...... 1.3 *bb.b (13) ...... OS4 ...... (14)...... - 0.22 (6) Acrylamide, I181 Sbww ...... 0.14 (7) Alachlor. (18) loclcw ...... 2.0 (11) Nlanr (a# N) (8) ...... 0.052 ...... 0.045 Chlordane, 0.44 - (e) DBCP, I MHUon Abrr pr Ma. (10) EDB, (11) Epichlorohydrin, 3. It le propoeed that propoeed 4. It le proposed to add a new 0 141.52 (12) Heptachlor, Subpart F, 0 141.51 be amended by to 40 CFR Part 141 to read as followe: (13) Heptachlor ep-ixlde, addlng (b) table entries (2) through (12) to 0 141.62 Rocommmded mnxlmum (14) PCBe, read as followe: contrmlnrnt kvolr for mlctobirl (15) Toxaphene. 0 141.61. Rocommnded mrxlmum conUI mI IU n1.. (b] . contrmlnrnt Iovolr for lnorgrnlc (a)Recommended maximum conUImlnrntr contaminant levele are zero for the (a) (Renewed] followlng inlcroorganlems: total (b) collforme, Ciurdio, and viruses. (b) Recommended maxlmum . . ~~~~ ~ (4) ~ldurb..Idurbw(mdbrmd.Idcrb*c cartumrnl RMCL h contaminant levels for the following fon...... ~ ...... ” ...... ” ...... 0.008 mgll microorganisme parametere are a6 (5) cultmml ...... ”...... ” ...... ””...... 0.036 (81 2.4-0...... 0.07 indicated Turbidity 0.1 Nephalometrlc (ne- ...... 0.62 (2)- ...... 0.05 Turbidity Unlt. (8)eh-lA’-hCh-...... 0.V (3) hbO#ta (mdtun m6 lono Ma’s) ...... ‘7.1 [FR 85-28417 Filed 11-12-85; 845 am) (8)b-1.2-DlcMomel hybr*...... 0.07 (41~u*m...... 1.5 Doc. (10) E- ...... ”...... 0.80 (5) cdmlun...... 0 005 mum cpe am-so-u

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S-074999 012z(07)( I2-NOV-BSI7: 144s) F4701 rev. 8-14-85