CPY Document

IA M)(XRAHS ON TH EVATION OF TH CACINIC RISK OF CHCA 'I MA:

Sorn Cabartes, Thiocarbates and Carbazides

Volur 12

This publication represents the views of an IA Working Group on the Evaluation of the Carcinogenc Risk of Chemcals to .M which net in Lyon, 9- 15 June 1976 lAC WORKING GROU ON TH EVATION OF TH CAINOENIC RISK OF CHCA TO MA: SC CATE, THICCTES AN CAIDES

Lyon, 9-15 June 1976

Mernbers1

Dr R.R. Bates, Associate Corssioner for Science, US Foo and Drug Adnistration, 200 C Street SW, Washington IX 20204, USA (Chairman)

Professor E. Boyland, TUC Institute of Occupational Health, London School of Hygiene and Tropical l1icine, Keppel Street, London ~LIE 7ll, UK

Dr G.J. van Esch, Head, Laratory for Toxicolog, Rijks Instituut voor de Volksgezondheid, Antonie van Leuwenhoelaan 9, Bilthoven, The Netherlands ( Vice-Chairman)

Dr D.E. Hathway, Senior Research Scientist, Cetral ToxicolCX.l Laratory, Imial Chercal Industries Lirted, Alderley Park, Cheshire SKIO 4TJ, OK Dr W. Li j insky, Frederick Cacer Research Centre, PO Box B, F'rederick, Maland 21701, USA Professor U. !-hr, Director, Abteilung ftr Exrimtelle Pathologie, Medizinische Hochschule Hanover, Kal Wiechert Allee 9, 3 Haover 61, FRG Dr S. D. Muhy, Assoiate Professor of Toxicolog, School of Pulic Heal th, Depart of Physiolog, Haard University, 665 Huntington Avenue, Boston, Massachusetts 02115, USA Dr V. B. Okulov, N. Petrov Research Insti tute of Oncolog, 68 Leningradskaya Street, Pesochny-2, Leningrad 188646, USSR Dr C. Ral, Stockholm Universitet, Wallenbrglalratoriet, Lilla Frescati, S- 104 05 Stockholm 50, Swden Dr B. Teichr, Akadere der Wissenschaften der DDR, Zentralinstitut ftr Krebsforschung, Lindenbrger Weg 80, 1115 Ber lin- Buch , GOR

Dr B. Terracini, Istituto di Anatorna e Istologia Patologica dell 'Università di Torino, Via Santena 7, 10126 Tuin, Italy

1 Unable to attend: Professor F. H. Sobels, Departmt of Radiation Genetics and Chercal Mutagenesis, State University of Leiden, Wassenaarseweg 72, Leiden 2405, Th Netherlands

3 Invited Guests

Dr B. Hildebrand, Toxicolog Depat, BASF Aktiengesellschaft, Bruckstrasse 60, D-6700 Ludwigshafen, FRG Dr O.H. Johnson, Senior Industrial Ecnorst, Chcal-Environmtal Prograr, Chercal Industries Center, Staford Research Institute, Menlo Park, ealifornia 94025, USA (Rapporteur sections 2.1 and 2.2) Dr V. von Schuller-Gtzburg, Mager, Chemcal Inforntion Servces - Euope, Stanford Research Institute, Pelikanstrasse 37, 8001 zürich, Swtzerland Mrs M.-T. van der Venne, Conrssion of the Euopean Ccmities, Health and Safety Directorate, Building Jean !-nnet A2jl15, Avenue Alcide-de-Gasperi, Kirchbrg, Luxemurg, Great Duchy of Luxemurg Representative fror the National Cacer Insti tute

Dr J .A. Cooper, Deputy Associate Director, Cacinogenesis Prograr, Division of Cancer Cause and Treatrt, National Cacer Institute, Bethesda, Maryland 20014, USA Secretariat Dr C. Agthe, Unit of Chercal Cacinogenesis (Secretary) Dr H. Bartsch, Unit of Checal Cacinogenesis (Rapporteur section 3.2) Dr L. Griciute, Chief, Unit of Environmntal Cacinogens Dr R. Montesano, Unit of Checal Cacinogenesis (Rapporteur section 3.1) Mrs C. Partensky, Unit of Chercal Carcinogenesis (Technical editor) Mrs 1. Peterschmtt, Unit of Checal Carcinogenesis, 'VJHO, Geeva (Bib i iogl'aph1:c yies earcher) Dr V. Ponomarkov, Unit of Chemcal Carcinogenesis Dr R. Saracci, Unit of Epiderolog and Biostatistics (Rapporteur section 3.3) Dr L. Torntis, Chief, Unit of Chercal Cacinogenesis (Head of the Programe) Dr G. Vettorazzi, Foo Additives Unit, WHO, Geeva Mr E.A. Walker, Unit of Environmtal Cacinogens (Rapporteur sections 1 and 2. 3) Mrs E. Ward, Montignac, France (Editor) Mr J .D. Wilbur, Unit of Chercal Carcinogenesis (Co-secretary)

4 Note ta the reader

Ever effort is made ta present the rrnogaphs as accuately as possible without unduly delaying their publication. Neverteless, rnstaes have ocurred and are still likel y to occu. ln the interest of all users of the se rrnogaphs, readers are reqested ta coicate any errors observed to the Unit of Chcal Cacinogenesis of the International Agency for Reseach on Cacer, Lyon, France, in order tht these ca be included in corrigenda which will appear in subseqent volurs.

Since the rrnogaphs are not intended ta be a review of the literature and contain only data considered relevant by the Working Group, it is not possible for the reader to deterrne whether a certain study was considered or not. However, research v.rkers who are aware of imrtant published data that may chage the evaluation are reqested to mae ther available to the abve-rnntioned address, in order tht they ca be considered for a possible re-evaluation by a future Working Group.

5 cxNl

BACKGROU AN PUE OF TH IA PRC ON TH EVATION OF TH CAIN:ENC RISK OF CHCA 'I MA ...... 9

SCOPE OF TH MONOHS 9

MEISM FOR PROOUCING TH MONCRAHS 10

GE PRIIPLES FOR TH EVATION 11

EXIA'IRY NOIS ON TH M)HS 14

GE RE ON CATES, THIcxTES AN CAIDES 23 TH M)HS Cabal 37 Chloroprophar 55 Diallate ...... 69 Dimthy lcabay 1 chloride 77 Disulf iram ...... 85 Dulcin ...... 97 Ethy 1 selenac ...... 107 Etyl tellurac ...... 115 Ferbam ...... 121 Ledate ...... 131 .Meb ...... 137 Methyl carbate ...... 151 Methyl selenac ...... 161 !-nuron ...... 167 Phenicabazide 177 Potassium bis (2-hydroxyethyl) dithocarbate ...... 183 Propha ...... 189 n- Propy 1 carba te ...... 201 Secarbazide (hydrochloride) ...... oo...... 209 Soum diethyldithocbate ...oo.....oo.oo...... oo... . 217 Thirar ...... 225 Zectran ...... "...... 237

7 Zineb ...... 245 ziram ...... 259 SUPPLEAR CORRGENA 'I VOLUMS 1-11 ...... 271 CUTIV INEX 'I MONcxHS ...... 273

8 BACKGROU AND PUSE OF TH IA PRCRA-l ON TH EVALATION OF TH CAINCIC RISK OF CHCA 'I MA

The International Agency for Research on Cacer (lAC) initiated in 1971 a program to evaluate the carcinogenic risk of chercals to ma. This program was supported by a Resolution of the Governing Council at i ts Ninth Session concerning the role of IA in providing goverrnt authorities with exrt, independent scientific opinion on environrtal carcinogenesis.

ln view of the ÌIrtce of the project and in order to expdite production of ITnogaphs, the National Cancer Insti tute of the United States has provided IAC with additional funds for this purse.

The objective of th program is to elalrate and publish in the forr of Ilnographs critical reviews of cacinogenicity and related data in the light of the present state of knowledge, with the final am of evaluating the data in terr of possible hum risk, and at the saine tir to indicate where additional research efforts are needed.

SCOPE OF TH M)NOGRAHS

The TInographs sunize the evidence for the carcinogenicity of indi vidual chercals and other relevant inforrtion on the basis of data coriled, reviewd and evaluated by a Working Group of experts. i' recom- rnndations are given concerning preventive neasures or legislation, since these rntters depend on risk-benefit evaluations, which seer best made by individual governnts and/or interntional agencies such as v\1O and IID.

Since 1971, when the program was started, eleven volums have been published1-11. As new data on chercals for which rrnographs have already ben prepared and new principles for evaluation becoin available, re- evaluations will be made at future meetings, and revised monographs will be published as necessary.

The ITnogaphs are distributed to international and governrntal agencies, are available to industries and scientists dealing with these chercals an are offeredto any interested reader through their world-wide

9 distribution as ~VH publications. They also fonn the basis of advice fror IA on carcinogenesis fror these subtances.

MEHAISM FOR PRODUCING TH M)N(HS

As a first step, a list of chemcals for possible consideration by the Working Group is estalished. IAC then collects pertinent references regarding physico-chercal characteristics, production and use*, occurrence

and analysis and biological data** on the se cornunds. The material is surized by an exprt consultant or an IA staff lTr, who prepares the first draft, which in sorn cases is sent to another exprt for corrts. The drafts are circulated to all lTrs of the ~'brking Group abut one IInth before the ireting. Duing the neeting, further additions to and

de let ions from the data are agreed upon, and a final version of comrts and evaluation on each comund is adopted.

Priority for the prepaation of IInographs Priori ty is gi ven rninl y to chercals belonging to paticular chemcal groups and for which there is at least sorn suggestion of carcinoenici ty from observations in animIs and/or ma and evidence of human expsure. However, the inclusion of a particular compound in a volume does not necessarily mean that it is considered to be carcinogenic. Equally~ the

fact that a substance has not yet been considered does not imply that it is ~i thout carcinogenic hazard.

Data on which the evaluation is based

With regard to the biological data, only published articles and papers already accepted for publication are reviewed. The IInographs are not intended ta be a full review of the literature, and they contain only data considered relevant by the Working Group. Research v.rkers who are awae

*Data provided by Chercal Informtion Services, Stanford Research Insti tute, Melo Park, Califon1Ìa, USA

**In th collection of original data referene was made to tl1e series of publications 'Surey of Caunds which have been Tes.ted for Cacinogenic , 12-1 7. Act ivi ty 10 of imrtant data (published or accepted for publica-tion) that may influence the evaluation are invited to rne them available to the Unit. of Chercal Carcinogenesis of the International Agency for Research on Cancer, Lyon, France.

The Working Group

The tasks of the Working Group are five-fold: (1) to ascertain that all data have been collected; (2) to select the data relevant for the evaluation; (3) to deterne whether the data, as sumized, will enable the reader ta follCM the reasoning of the corrttee; (4) to judge the significace of results of exrimntal and epiderological studies; and (5) ta mae an evaluation.

The rrs of the Working Group who participated in th consideration of paticular substaces are listed at the beinning of each publication. The rnrs sere in their individual capacities as scientists and not as representatives of their governnts or of any organization with which they are affiliated.

GENRA PRINCIPLES FOR TH EVATION

These general principles for evaluation of carcinogenicity were elalrated by previous Working Groups and also applied to the substances covered in this volur. Terrnolog The ter 'chemcal carcinogenesis' in i ts widel y accepted sense is used to indicate the induction or enhancert of neoplasia by chercals. It is recogized that, in the strict etylogical sense, this Jcenn ITans the induction of cancer; however, comrn usage has led to i ts emloyit ta dente the induction of various types of neoplasr. The terrCl tururigen , oncogen' and ' blastaren' have all been used syonyrusl y wi tl1 cacinogen al though occasionall y 'tUIurigen' has been used speificall y ta denote the induction of benign tUlurS.

11 Response to carcinogens ln general, no distinction is made betwen the induction of tururs and the enhancernt of turur incidence, although it is noted that there may be fundarntal differences in mechanisr that will eventually be elucidated. The respnseof e:x-priintal anirls to a carcinogen rny take several forr: a significant increase in the incidence of one or rrre of the sar typs of neoplasr as found in control anÍIna.ls; the occurrence of typs of neoplasr not observed in control animls; and/or a decreased latent period for the production of neoplasr as corrred with that in contrl anls. Pui ty of the camunds tested

ln any evaluation of biological data with respect to a possible carcinogenic risk, particular attention mut be pad to the puri ty of the chercals tested and to their stabili ty under conditions of storage or admnistration. Informtion on purity and stability is given, when available, in the ITnographs.

Qualitative aspects

ln may instances, bath benign and rnlignant tururs are induced by chercal carcinogens. There are so far f6i recrded instaces in which onl y benign tururs are induced by chercals that have been studied extensively. Their occurence in exprirtal system has been taken to indicate the possibility of an increased risk of malignt tururs also. ln exprimtal cacinogenesis, the typ of cancer seen may be the sar as that recorded in hum studies, e. 9 ., bladder cancer in ma, monkeys, dogs and hamters after admistration of 2-naphthy lamne. ln other instances, however, a chercal may induce other typs of neoplasr at different sites in various species, e. 9 ., benzidine induces hepatic carcinoma in rats but bladder cacinor in ma. Quanti tati ve aspects

Dose-response studies are imrtant in ti1e evaluation of hur and anl carcinogenesis: th confidence with which a carcinogenic effect can be estalished is strengtened by ti1e observation of an increasing

12 incidence of neoplasm with increasing e:xsure. ln addition, such studies forr the only basis on which a miiml effective dose can be established, alla.ing sorn comison wi th data for hum e:xsure.

Corisons of comp:mnds with regard ta poteri can only be made when the substances have ben tested sirl taeousl y .

Animl data in relation to the evaluation of risk to man

At the present tim no attert can be made to interpret the animl data directly in terr of hur risk, since no objective criteria are available to do so. The cri tical assessmnts of the validi ty of the animl

data given in the se rrnogaphs are intended to assist national and/or international authorities in maing decisions concerning preventive rrasures or legislation. ln this connection attention is drawn to WHO recomrdations in relation to food additives1 8, drgs19 and occupational carcinogens2o. Evidence of human carcinogenici ty

Evaluation of the carcinogenic risk to ma of susicted environmental agents rests on purel y observational studies. Such studies must cover a sufficient variation in levels of hum expsure to allow a rraningful relationship between cacer incidence and exposure to a gi ven chercal to be estalished. Difficulties arise in isolating the effects of individual agents, hcwever, since peple are usually e:xsed to multiple carcinogens.

Th initial suggestion of a relationship between an agent and disease often corrs from case reports of patients with sirlar e:xsures. Varia- tions an tim trends in regional or national cancer incidences, or their correlation with regional or national 'e:xsure' levels, may al50 provide valuale insights. Such observations by therel ves, however, cannot in rrst circurtaces be regarded as conclusive evidence of carcinogenicity. The rrost satisfactory epiderological rnthod is to compe the cancer risk (adjusted for age, sex and other confounding variables) alIDng groups or cohorts, or arng indi viduals expsed to various levels of the agent in question, and arng control groups not 50 e:xsed. Ideally, this is accom- plished directl y, by following such groups forwd in tim (prospecti vel y) ta deterrine tim relationships, dose-response relationships and other aspects of cancer induction. Lage cohorts and long observation periods

13 are reqired to provide sufficient cases for a statistically valid compison. An al ternati ve to prospective investigation is to assemle cohorts from past records and to evalua-te their subseqent 1IDrbidity or rrrtality by nean of iædical histories and death certificates. Such occupational carcinogens as nickel, ß-nahthy1amæ, asbestos an benzidiæ have ben confir by this method.

Another rnthod is ta coe the past expsures of a defined group of cacer cases with those of control sarles from the hospital or general population. Ths does not provide an absolute rnasure of carcinogenic risk but ca indicate the relative risks associated with different levels of expsure.

Indirect rn (e. g ., interviews or tissue residues) of measuring exsures which rry have conrnenced rny years before can consti tute a rrjor source of error. Nevertheless, such 'case-control' studies can often isolate one factor from several suspected agents and can thus indicate which substance should be follcwed up by cohort studies.

EXLA'IRY OOS ON TH M)NCHS

ln sections l, 2 and 3 of each rrnogaph, except for rnnor rerarks, the data are recorded as gi ven by the author, whereas the corrrrnents by the Working Group are given in section 4, headed 'Corrts on Data Rej:rted and Evaluation' . Chercal and Physical Data (section 1) Th Chercal Abstracts Reistry Serial Nmnr and the la-test Chercal Abstracts Nam are recorded in this section, tagether wi tll other synonyr an trade nas. Chercal and physical propeties include, in particular, data that rnght be relevant to carcinogenicity (for exanple, lipid solubility) and those that concern identification. Data for which no reference is given are usually taken from stadad reference boks such as the Merck Tndex21 or the Handbook of Chemistry and Physics22. All cheroical data in this section refer to the pure substace, unless otherwise s~cif ied. 14 Production, Use, Occurence and Analysis (section 2) The purse of ths section is to indicate the ext81t of possible hum expsure. With regard to data on production, use and occurrence, IAC has exÜlalrated with th Stanford Research Institute, USA, with the support of the National Cacer Institute of the USA. Since cancer iS a delayed toxic effect, past use and production data are also provided.

The United States, Europe and Japa are reasonably representative industrialized areas of the v.rld, and if data on production or use are available from these countries they are reported. It should not, hc:ever, be inferred that these nations are the sole or even the major sources of any ini vidual chercal. Pruction data are obtained frcm toth governtal and trade publications in the thee geoaphic areas. Informtion on use and occuence is obtaied by a comprehensive review of published data, corrleinted by direct contact wi th rnufacturers of the chercal in questions. ln an effort to provide estirtes of production in sone Euopean countries, the Staford Research Insti tute ln Zurich sent questionnaires to certain Euopean companies thought ta produce carbamtes, thiocarbates and carbazides. The replies have be included in the indi vidual rrnographs.

Statennts concerning regulations in sone countries are rrtioned as exales only. They may not reflect the rrst recent situation, since such legislation is in a constant state of chage; nor should i-t be taken to lily tht other countries do not have simlar reglations. ln the case of drgs, rrtion of the therapeutic uses of SUd1 chercals does not necessarily represent presetly accepted therapeutic indications, nor does it lily judgemt as to their clinical efficacy. The purse of the section on anl ysis is to gi ve the reader an indication of nethods available in the literature. No attert is made to evaluate the nethods quoted.

15 Biological Data Relevant ta B1e Evaluation of Cacinogenic Risk ta M: (setion 3) The rrnogaphs are not intended ta consider all reported studies. Sorn studies were pursely orntted (a) because they ~re inadeqate, as judged from previously describd criteria23-26 (e.g., tao short a duration, tao few anirls, por surival or too sill a dose) ; (b) l:cause they only confinr findings which have already been fully describd; or (c) because they were judged irrelevant for the purse of the evaluation. Hc:ever, in certain cases, reference is made ta studies which did not rrt estalished criteria of adeqacy, paicularly when ths informtion was considered a useful supplemt to other reports or when it was the only data available. Their inclusion does not, hc:ever, imly acceptance of the adeqacy of their exprirental design. ln general, the data recorded in ths section are sumized as given by the author; however, certin shortcorgs of reporting or of exri- metal design that were comnted upn by the Working Group are gi ven in square brackets. Carcinogenici ty and related studies in anls: ~Ention is made of all routes of admnistration by which B1e cornund has been ade0ately tested and of all species in which relevant tests have ben carried out. ln IISt cass, animl strains are given; general characteristics of rruse strain have been reported in a recent review27. Qutitative data are given to indicate the order of magnitude of the effective doses. ln general, the doses are reportd as thy appe in the origiI1 J?per; sorntims conversions have been made for better comparison. Oter relevant biological data: Sar ID 's are given, and other 50 data on toxicity are included, when considered relevant. 'l netalic data included is restricted to studies showing Bie rntablic fate of the chercal in animls and ma, and conpisons of animl and hlI data are made when possible. Oter rntalic informtion (e.g., absorotion, storage and excretion) is given when B1e Working Group considered that it Vluld be useful for the reader to have a l:tter rnderstanding of B1e fate of the cornund in the l:y. When the cacinogenici ty of knCM rntali tes has

16 ben tested, this also is reported.

Mutagenicity data are also included¡ the reasons for including ther and the principles adopted by the Working Group for cl1eir selection are outlined below.

May, but not all, mutagens are carcinogens and ¿nee Vel'so: ¡ cl1e exact level of correlation is still under investigation. Neverteless, practical use rny be made of the available mutagenicity test procedures cl1at combine microbial, rnlian or ocl1er anl cell sys-terns as genetic targets wi th an in vi t-l'O orin vivo metallic activation system. The results of relatively rapid and inexsi ve mutagenici ty tests on non-hurnan organisrn lffY help to pre-scree chercals and rny also aid in clie selection of cl1e most relevant animl speies in which to carry out long-terrri carcinogenici-ty tests on these chercals. The role of genetic alterations in chercal cacinogenesis is not yet fully understoo, and cl1erefore consideration must te given to a variety of changes. Alcl10Ugh nuclear DNA has b2en defined as clie main cellular target for the induction of genetic changes, other relevant targets have ben recogized, e. g., mi tochondrial DNA, enzymes invol ved in DNA synthesis, repair and recombination, and the spindle apparatus. Tests to detect the genetic activity of chercals, including gene mutation, strctural and numrical chromsornl changes and nntotic reconinination, are available for non-hum moels ¡ but not all such tests ca b2 applied at present to hum cells. Ideally, an appropriate mutagenicity test system would include ti1e full netablic comptency of ti1e intact hum. Since the developmet or application of such a system appears ta b2 impossible, a bactery of test system is necessar in order to establish the mutagenic ¡:tential of chercals. There are may genetic indicators and netablic activation system available for detecting mutagenic activity¡ they all, hawever, have individual advantages and limtations. Since may chercals reqire metablism to ilì active forr, test system which do not tae this into account may fail to reveal cl1e full range of genetic damge. Furcl1enrre, since sone reacti ve netalli tes

17 with a lirted lifespa may fail to reach or to react with the genetic indicator, ei ther because they are further netalized to inactive compounds or because they react with other cellular constituents, mutagenicity tests in intact anls may gi ve false negati ve resul ts.

It is difficult in the present state of knowledge to select specific mutagenicity tests as being the most appropriate for the pre-screening of substaces for possible carcinogenic acti vi ty . However, greater reliance may be placed on data obtained from those test systems wÌ1ich (a) cerrt identification of the nature of induced genetic changes, and (b) deinstrate that the changes are transr tted ta subseqent generations. Mutagenici ty tests using organism tht are v.ii-w1derstoo genetically, e.g., E.schel'"Ji- chia cOl1:.. SalmoneUa typhimuriz-un.. SacchoJ'omuces and Jl'Osopt21:la, neet these reqiremnts.

Al though a correlation has often been observed between the abili ty of a chercal to cause chromsome breakge and its ability to induce gene mutation, data on chromosoml breakage alone do not provide adeqate evidence for mutagenci ty, and therefore less weight should be gi ven to pre-screening tht is based on the use of peripheral leucote cultures.

Because of the conilexty of factors that can contributeto reproductive failure, as well as the insensitivity of the rnthod, the dominant lethal test in the rnl does not provide reliable data on mutagenici ty . A large-scale systemtic screening of compunds to assess a correlation between mutagenici ty and carcinogenici ty has sa far been caried out onl y with the bacterial/rnlian liver rncrosone system. ìbtwithstanding the deinstration of the mutagenici ty of rny knOt cacinogens to Sa lmone L la typhimurium in the presence of li ver rncrosomal system, the possibili ty of false-negative and false-positive results must not be overlooked. False-negatives rnght arise as a conseqence of mutagen specificity or from failure to achieve optiml conditions for acti vationz:r ~'i ti'o . Alternative test system mut be used if there appear to be substantial reasons for suspecting that a chercal VJich is apparently non-mutagenic in a bacterial test system may neverteless be potentiall y carcinogenic. Conversel y, sem chercals found to be mutagenic in this test may not in fact have mutagenic activity in other system. 18 For more detailed informtion, see references 28-35.

Observations in ma: Case reports of cacer and epidemiological studies are surized in this section.

Corrts on Da ta Reported and Ev 1 ua tion (section 4)

This section gives the critical view of the ivorking Group on the data reported. It should be read in conjunction with the 'General RerlBrks on Cabates, Thiocarbani.tes and Carbazides', p. 23.

Animl data: The anirl speies metioned are those in which the carcinogenicity of the substances was clearly dernstrated, irrespective of the route of admnistration. The route of administration used in exoi- mental anirls that is sirlar to the fDssible hum ex¡sure (ingestion, inhalation and skin expsure) is given p:icular metion. ln nost cases, tumur sites are also indicated. Exrirents invol ving a fDssible action of the vehicle or a physical effect of the agent, such as in studies by suutaneous injection or bladder irlanation, are includedi however, the results of suc tests reqire careful consideration, paricularly if they are the only ones raising a suspicion of carcinogenicity. If the substance has produced tumurs after pre-natal exsure or in single-dose exrirts, ths also is indicated. This siIsection should be read in the light of comrts made in the section, 'Anirl Data in Relation to the Evluation of Risk to Ma' of this introduction.

Hum data: ln sorr cases, a brief statemt is made on possible hum expsure. The significance of epiderological studies and case reports is discussed, and the data are interpreted in terr of possible hum risk.

19 References

1. lAC (1972) IA Monogaphs on the Evluation of Carcinogenic Risk of Chercals ta Ma, l, Lyon

2. lAC (1973) IA Monographs on the Evluation of Carcinogenic Risk of Cheinicals ta l'1a, 2, Sone lnorganic and Organonetallic CoITunds, Lyon

3. lAC (1973) IA Monographs on the Evluation of Carcinogenic Risk of Chercals to l1a, l, Certain Polycyclic Aroliatic Eydrocarl:x:ms and Heterocclic Cornunds, Lyon

4. IA (1974) IA Monogaphs on the Evluation of Cacinogenic Bisk of Chercals ta Ma, l, Sa Arorrtic Amnes, Hydrazine and Related Substaces, N-Nitroso Counds and ~tiscellaneous Alkylating Agents, Lyon

5. lAC (1974) IA Monogaphs on the Evluation of Cacinogenic Risk of Chercals ta ~Bn, 5, Sor Organoclorine Pesticides, Lyon

6. lAC (1974) IA Monographs on the Evluation of Carcinogenic Risk of Chercals ta Ma, 6, Sex Honrnes, Lyon

7. lAC (1974) IA M:mogaphs on the Evluation of Carcinogenic Risk of Chercals to Ma, 7, Sa Anti-thyroid and Related Substaces, Ni trofurans and Industrial Checals, Lyon

8. IA (1975) IA ~bnogaphs on the Evaluation of Cacinogenic Risk of Chercals ta Ma, 8, Sa Aromatic Azo Coruncls, Lyon

9. lAC (1975) IA Monographs on the Evluation of Carcinogenic Risk of Chewicals to Ma, 9, Sor Aziridines, N-, 5- and O-~lustards and Selenium, Lyon

10. lAC (1976) IA Monographs on the Evluation of Cacinogenic Risk of Chercals to Hem, 10, Sa Naturally Occuring Substances, Lyon

11. IA (1976) lAC Monographs on the Evaluation of Cacinogenic Risk

of Chercals to Ma, 11, CadmÍlun, Nickel, Sa F.xides , Miscella.- neous Industrial Chrrals and Geeral Consiclerations on Volatile Anaesthetics, Lyon

12. Har~ll, J.L. (1951) Surey of Crnunds which have l€n Tested for Cacinogenic Acti vi ty, Washington rx, US r:-0verrnent Prin ting Office (Pulic Health Service Publication 1\0. 149)

13. Shubik, P. & ~ll, J.L. (1957) Surey of CCIunds which have been Tested for Carcinogenic Acti vi ty, í'ia.c;hington OC, us Governt Printing Office (Public Heal th Seice Pulication No. 149: Supplemnt 1) 20 14. Shubik, P. & Ha~ll, J.L. (1969) Surey of Ccrunds which have been Tested for Carcinogenic Acti vi ty, Washington OC, US Governt Printing Office (Public Health Serice Pulication No. 149: Suppleit 2)

15. Carcinogenesis Program National Cancer Institute (1971) Surey of Corri.mds which have been Tested for Carcinogenic Activi ty , Washington De, US Governnt Printing Office (Public Health Service Pulication No. 149: 1968-1969)

16. Carcinogenesis Prograr National Cancer Institute (1973) Surey of Coniunds which have been Tested for Carcinogenic Acti vi ty , Washington De, US Governnt Printing Office (Public Health Service Pulication No. 149: 1961-1967)

17. Carcinogenesis Prograr National Cacer Institute (1974) Surey of Corruns which have been Tested for Carcinogenic Acti vi ty , Washigton De, US Goverrt Printing Office (Public Health Service Pulication No. 149: 1970-1971)

18. WHO (1961) Fifth Report of the Joint FAO/WO Exprt Comttee on Foc Addi ti ves. Evaluation of carcinogenic hazard of fcx additives. Wld Hlth Org. techn. Rep. Ser., l'. 220, pp. 5, 18, 19

19. WHO (1969) Report of a WHO Scientific Group. Principles for the testing and evaluation of drgs for cacinogenici ty . wid Hl th Org. techn. Rep. Ser., No. 426, pp. 19, 21, 22

20. WHO (1964) Report of a WHO Exrt Cottee. Prevention of cancer. Wld Hlth Org. techn. Rep. Ser., No. 276, pp. 29, 30

21. Stecher, P .G., ed. (1968) The Merck Index, 8th ed., Raay, ID, Merck & Co. 22. Weast, R.C., ed. (1975) CRC Hadlk of Chers-tr and Physics, 56th ed., Cleveland, Ohio, Chemcal Ruber Co.

23. WHO (1958) Second Report of the Joint FAO/WO Exprt Canittpe on Foo Additives. Procedures for the testing of intentional foo addi ti ves to establish their safety for use. Wld Hl th Org. techn. Rep. Ser., No. 144

24. WHO (1961) Fifth Report of the Joint FAO/WO Exprt Cornttee on Foo Additives. Evaluation of cacinogenic hazard of foc additives. wid Hlth Org. techn. Rep. SeL, No. 220 25. WHO (1967) Scientific Group. Procedures for investigating intentional and unintentiona1 foo addi ti ves . Wld Hl th Org. techn. Rep. SeL, 1'. 348

26. Berenlum, L, ed. (1969) Cacinogenicity testing. UICC techn. Rep. Ser., 2

21 27. Cornttee on Stadadized Geetic Ncclature for Mice (1972) Standardized nomclature for inred strains of mice. Fifth listing. Cacer Res., 32, 1609-1646 28. Batsch, H. & Grover, P.L. (1976) Chercal carcinogenesis and ITn.lta- genesis. ln: Syingtn, T. & Carter, R.L., eds, Scientific Foundations of Oncolog, Vol. IX, Chcal Cacinogenesis, London, Heinem l1ical Boks Ltd, pp. 334-342

29. Hollander, A., ed. (1971) Checal Mutagens: Principles and JViethods for Their Detection, Vols 1-3, New York, Plemini Press 30. !-ntesano, R. & 'Imatis, L., ed (1974) Chcal Cacinogenesis Essays, Lyon, IA (IA Scientific Pulications No. 10)

31. Ral, C., ed. (1973) Evaluation of genetic risks of enviro:rtal chercals: report of a sysium held at Skokloster, Sweden, 1972. Ario Speial Report, No. 3

32. Stoltz, D.R., Poirier, L.A., Irving, C.C., Stich, H.F., Weisburger, J.H. & Grice, H.C. (1974) Evluation of short-ten tests for carcinogenicity. Toxico1. app1. Phaco1., 29, 157-180

33. WHO (1974) Report of WHO Scientific Group. Assessmt of the carcinogenicity and rntagenicity of chercals. Wld Hlth Org. techn. Rep. Ser., No. 546

34. !-ntesao, R., Batsch, H. & TOItiS, L., eds (1975) Screening Tests in Chemcal Cacinogenesis, Lyon, IA (!A Scientific Puli- cations No. 12)

35. Corrttee 17 (1975) Environrtal rnutagenic hazards. Science, 187, 503-514

22 GEN RE ON CATES, THICCTE AND CAIDES

ln ths volmn of rrnogaphs, a numr of cabate esters, dialkl- dithocarbates, ethylene bisdithocarbates and cabazides are considered, which are or have ben produced and for whch a cacinogenic effect or a suspicion of carcinogenicity has teen reported.

The Working Group was aware of unublished data concerning sor of these canunds. However, in view of the principle followed in these monographs not to use data which are unavailable to the reader, such infor- mation was not considered by the WJrking Group. Th rrrs exressed concern over the long delay which sotims occus in the publication of exprimntal data. For rny of the chemcals considered in ths volmn (probal y for rrre th in any other volmn of this series), the Working Group was unle to rne an evaluation of carcinogenicity: the data w=re either quantitatively or qualitatively indeqte. ln addition, there was a consistent lack of epiderological studies. ln this context, it should te ¡:inted out that the report which gave the resul ts of the long-terr testing of abut 130 environrntal checals (Innes et al., 1969), upn which rrst of the evaluations of carcinogenicity of the conpunds considered in this volmn were based, was published in 1969. It is widely accepted that exrimtal data on the carcinogenici ty of a checal ta which hur are exsed provide a goo indication of the necessity for epiderological studies¡ however, in spite of the fact tht there is hur exsure ta rrst of the chemcals for which evidence of carcinogenicity or a suspicion of cacinogencity wa provided by ths large study, discouragingly little epiderological v.rk has resul ted in the seven years which have follc:d.

ln so far as the exrimntal evidence is concered, there are tw main points which the Working Group v.uld like to point out: (1) the chemcals considered in the monogaphs are selected arng those for whch not onl y sor suspicion of carcinogenici ty exists but for whch, wi th a fev exceptions, there is evidence of their use and production and social i.rtce. Therefore, if the available data were insufficient for the Horking Grup ta rne an evaluation of a chercal considered in this series, further testing 23 of that chercal should be considered of high priority; (2) it is irative that carcinogenicity testing te carried out follcwing certain basic reqremts in order that the results ca be properly evaluated. The Agency is planing a discussion of protocols for testing wl-ich ca be agreed upon interntionally, but there are already several publications which give satisfactory infonrtion on the proper rung of cacinogenicity tests (Berenblum, 1969; Golbrg, 1974; NCI, 1975). The cornuns considered in this vol1. are used as insecticides, fungicides or herbicides, as accelerators in the vulcanization of ruber, as drgs or as chercal interrdiates in the maufacture of drgs, pesticides or resins. Sureys in the US, Euope and Japan have ShCM that a numr of the cornunds are produced in quanti ties of up ta several thousad kg per anum; production of sor of the cOIunds rny have been as high as 5 million kg in recent years, and for one (cabal) 24 million kg W2re produced in the us in 1971. Although their occurrence in the environnnt is thus to be exed, there is little data on thir persis"tence and breakdcw .

As rnntioned abve, a substantial proportion of the biological infor- mation related to carcinogenicity in exprimntal animls included in the present series of monogaphs deri ves from a large-scale study of abut 130 chercals. ln this study, each chercal was tested bath by long-terr feeding and by single subutaneous injection in tV\ hybrid strains of mice. A partial sum of the results was published in 1969 (Innes et al., 1969), an the details of each exprimt are available in a separate publication (NlIS, 1968). ln bath reports, results for each strain, sex and route of admnistration are gi ven as numrs of animls developing t1.urs and not as nums of tuiurs found at each si te; nor is the age at death of tUJur-bearing rnce gi ven. . Therefore, precise anal ytical nethods, such as the constrction of lifetirl1e tales, could not be used, and ~che statistical significance of the results has ben established using the X 2 rnthod, systemtically introducing Yates' continuity correction (even when the authors may have used a different procedure). Results obtained from anirls receiving the sam cornund by different rou~ces or belonging to

24 different strains were evaluated sepaately by the vbrking Group; however, in sorn cases, the statistical significance was estalished by cornining resul ts obta in the bK sexes of the sam strain recei ving the sam treatrnt.

There have ben relXrts that rny N-alklureas or N-alk-ylcarbaca.tes (an thocbates) react with nitrite under rnldly acidic conditions to forr N-nitroso compunds (Hirvish, 1975; Sen et al., 1974). Nitrite is fo:i by bacterial reduction of nitrate, which is acculated to signifi- catl y high concentrations in sor vegetales (e . g., spinach and bets) on stading in air, especially after cooking (Ashton, 1970; Phillips, 1968). The 6-10 ppr nitrite found in hum saliva result from reduction of nitrate by bacteria in the ITuth (Tanenbum et al., 1974). A major source of nitrite is cured rrts, in which concentrations of up to 100 ppm are corrn (Ashton, 1970). Table L lists severalalkylureas, alkylcarbates and thiocarbates that have ben shaw to react with nitrite in chercal syste. Th formtion of N-nitrosoirthylai-l1Ì.ne by the action of micro- organism in sewage and soil a:mtaining 0.1% thirar has ben reported to occu urer exrirtal conditions (Ayanab et al., 1973). N-Nitroso counds derived sirlarly frcm otlier cabarte pesticides could also occur in th environit.

It is not knCM to what extent the forrtion of N-nitroso derivatives by reaction of carbarte pesticides wi tll ni tri te, as sho. in chemcal system, could tae place in ma in vivo. ExtraDOlation of chercal findings ta the significace of such reactions in ma is complicated by several factors, including drastic differences in tl concentrations of the reactats, differences in pH and the possible presence of accelerators an inhi tors of the reaction. The N-nitrsoalkylames (N-nitrsoethyl- and N-nitrsodithylames) , fo:i fror dial 1 thiocarbate pesticides and ni tri te, are patent carcinogens and mutagen. The N-nitroso derivatives of several N-alkylcarbartes and N-alklureas have given ri se to rnlignant t11urs in exorirnntal ans at smll doses; the se include N-ni trosobenzthiazuron (Ungerer et aL., 1974) an N-nitrosocbal which induce tururs in raJcs (Eisenbrand et al., 1975, 1976; Lijinky & Taylor, 1976). N-Nitrosocbaryl has also

25 Table L

Reactions of alklureaq, alklcabates an thocarbates with nitrite

COIund N-Ni troso deri vati ve forrd

Benzthazuron N-N~trosobenzthiazuron (N- (2-benzothazolyl) -NI- (Eisenbrand et al., 19740; rnthy lurea) Ungerer et al., 1974) Cabal N-Nitrosocarbarl (Eisenbrai1d et al., 1974b; Elespur & Lijinsky, 1973) Disulf iram N-Ni trosodiethy lamne (Lijinsky et al., 1972)

Dulcin N-Ni trosodulcin (Miish, 1975) Fenuron N-Nitrosodimthy lamne (l, 1 -dirthy 1 - 3-pheny lurea) (Hirvish, 1975) Ferba N-Ni trosodimthy lamine (Sen et al., 1974) Propoxu N-Nitrosopropoxu (2-isopropoxyhenyl -N- (Eisenbrand et al., 1974b) rnthy lcarbate) Thirar N-Nitrosex:1imthylamne (Egert & Greir, 1976; Sen et al., 1974)

Ziram N-Ni trosodimthy lame (Eisenbrand et al., 1974a,b;

Sen et al., 1974)

26 induced malignant transformtion in Balb/3T3 rruse cells in culture (Quarles & Tent, 1975). May of the carunds considered in the present volur, e. g ., the N-ræthylcarbamtes, carbaland zectran, the N,N-diisopropylthiocarbarte, diallate, and the dithocbates, zineb and ziram, cause central nervous system malfunction under conditions of severe rxisoning (Best & :Murray, 1962; Hodge et al., 1956; Kornova & Zotkina, 1971; Pestova, 1966; Richardson & Batteese, 1973; Ryazanova et al., 1972). The N-methylcarbates, carbarl and zectran, have been ShCM to inibit acetylcholinesterase activity

(for references, see indi vidual rrnographs) . Hydrolytic fission is the principal prim rætalic paUiway for the simle ester carbates and dÜæthylcarbayl chloride (von Hey et al., 1974; Queen, 1967), and ths biotransformtion applies to a lesser extent to the arortic N-rnthylcabates, cabal and zectran, the N-phenylcarbamtes, chloropropham and prophar, and the N-phenyldialklurea, rrnuron. ln addition, while ring hydroxylation is a feature of the rætalisr of the arorntic N-rnthylcarbates and of the N-phenylcarbates, oxidative N-dealkylation takes place with the N-phenyldialklurea; but N-phenylcarbartes undergo oxidation of the isopropyl group (without dealkylation) (for references, see individual irnogaphs). Epxidation and subseqent ring fission by hydrolysis (Sullivan et aL., 1972) and by reaction with glutathione (Bend et aL., 1971) are imrtat biotransforntions of carbaryl. ln the N- dealklation pathway, carbal (Dorough & Casida, 1964; DJrough et aL., 1963; Leeling & Casida, 1966) and zectran (Oonnithan & Casida, 1966) afford reactive rnthylolardes, and cabal, like the simle ester carbamates, also undergoes N-hydroxylation (Loke, 1972).

Reductive fission of the disulphide bond of the tetraalkyltliiurar disulphides, disulfiram (Do et al., 1949) and thiram, occurs Úi vivo, and the resulting dialkyldithiocarbates have a netalic pathway in corrm::m with those belonging ta the sodium (Strönn, 1965), iron (ferbam) and zinc (zirar) salts (Hodgson et al., 1975), e.g., fission of dialkvlditliiocarbate into carbon disulphide and dialkylarne and N-glucuronidation of tlie dialkyl- dithocbate itself. The ethylene bisdithocarbartes, maeb and zineb, undergo other rntalic changes, including hydrol ytic reactions, rearrange- 27 irts, ring fission with extrion of carOOn disulDhide an ring closure (Seidler et al., 1970; Truaut et al., 1973).

The fact tht dithylcabayl chloride behaves as a direct-acting carcinogen (Van Duuren et al., 1972) is consistent with the production in vivo of the corresponding caroonium ion, which reacts with nucleophiles (Hall & Lueck, 1963). Ethylenethiourea, which produces thyroid carcinonas in rats and liver-cell tumurs in mice after its oral admnistration (IA, 1974), is forr fror ethylenebisdithocarbates, such as mneb and zineb, ooth by rntalic processes and by coking (Watts et aL., 1974). Carbal, sercarbazide hydrochloride and n-propyl cabaina.te, the ethylenebisdithiocabartes, rneb and zineb, the dialkyldithiocarbarte, ferba, and the tetraalkylthiuram disulphide, thiram, are teratogenic in exprÌIntal anirls (for references, see indi vidual rrnographs) .

Mutagenici ty data on the carbate cOimunds are lir ted and largel y restricted to bacteria and plant material. It is possible that in higher plants sorn chercals can undergo rntallic conversion into patent muta gens , as illustrated by the rntallism of atrazine (2-chloro-4-ethylarno-6- isopropy lare-s-triazine) in naize (P lewa & Getile, 1975, 1976). Further- irre, the irst pronounced genetic effect of soi of the cabates is inhibition of spindle-fibre formtion, and this ca rrst easily æ studied in plants. Mutagenicity data in mals or mn W2re available for seven of the cornunds considered. Several bisdithocarbates are goitrogenic in lalratory anircals, and there is sone suggestion that ths effect has occured in nen expsed to thirar. The relationship betwen goitrogenicity and carcinogenicity, and its practical conseqences, have been dealt with elsewhere (IAC, 1974; WHO, 1974) but have not ben fully elucidated.

From investigations in animls of the relationshiD between the st.ructure of the dithocarbates and the occurence of acetaldehyde in the bloo after ingestion of ethanol, it appears that irst of the alkyldithiocarbates (e.g., ferbam and zirar) and thiurar sulphides (e.g., disulfirarn and thirar) induce accuation of acetaldehyde. The ethylenebisdiiJ1iocarbamates (e.g., zineb and rneb) had no effect on the acetadeyde level in the blCX.

28 On the whole, dithiocarbartes with a free H-ator on the N-ator did not srow the dithocarbate-ethol reaction in an:is. There are indications that observations in studies of occupational health correspond with these results from animl studies (van Lüen, 1972).

Of the cornunds considered in this volur, disulfirar, dulcin, ethyl tellurac, ledate, rrnuron, sercarbazide hydrochloride and zectran are currently being tested for carcinogenicity in exprirtal anirls, and an epiderological surey is being carried out on dimthylcarbayl dlloride (IA Informtion Bulletin on tl1e Surey of Chercals Being Tested for Carcinogenicity, No. 6, 1976). Several other cabarte cornunds (listed belCM) inhibit turur grCM but are also carcinogenic in animls. Since there was no available evidence of past or current hlT exsure to these cornunds, rrnographs on them were not prepared: l, 1 -dipheny 1 - 2-propyny 1 - N-cyclohexy 1 carbate (Harris et al., 1969); 1,1-bis(4-fluorophenyl)-2-propynyl-N-cycloheptyl cabarte and l, l-bis (4-fluorophenyl) -2-propyyl-N-cyclootyl carbate (Haris et al., 1970); 1- (4-chlorophenyl) -1-phenyl-2-propynyl cabate (Harris et al., 1972); and 1,4-bis(4-fluorophenyl)-2-propynyl-N-cyclootyl carbate (weisburger et al., 1975). May other ureas and carbate corunds, used as agricul tural chemcals (Epstein & Legator, 1971; Kuh & Dorough, 1976) and/or drgs (Stecher, 1968), are produced cornrciall y, but no data on their carcinogenicity were available to the Working Group.

29 References

Ashton, M.R. (1970) The Occurence of Nitrates and Nitrites in Foos, Leatherhead, Surrey, The British Foo Iv'lufacturing Industries Research Association Ayan, A., Verstraete, W. & Alexader, ~1. (1973) Possible microbial contribution ta nitrosarne forrtion in sewage and soiL. J. nat. Cancer Inst., 50, 811-813

Bend, J.R., Holder, G.M., Protos, E. & Ryan, A.iT. (1971) Water-so1uble metalites of carbal (l-naphthyl-N-rnthylcarbarte) 5n lIDuse liver preparations and in the rat. Alitr. J. bioL. Sci., 24, 535-546

Berenblum, L, ed. (1969) Carcinogenicity testing. UICC techn. Rep. Ser., 2 Best, E.M., Jr & Muray, B.L. (1962) Observations on v.rkers exposed ta sevin insecticide: a prelirnar report. J. OCCUpa M2., !, 507-517

Dorn, G., Fredga, A. & Linderholm, H. (1949) A rrthod for quantitative deterration of tetraethylthiuram disulphide (Antabuse, Abtiml) and its reduced forr, diethyldithocarbarc acid, as found in excreta. Acta chem. scad., 3, 1441-1442

Dorough, H.W. & Casida, J.E. (1964) Nature of certain cabate rætalites of the insecticide sevin. J. agric. Fd Ch., 12, 294-304

Dorough, H.W., Leling, N.C. & Casida, J.E. (1963) Non-hydrlytic pathway in rntablism of N-rnethy lcarbate insecticides. Science, 140, 170-171

Egert, G. & Greir, H. (1976) Forrtion of diithylnitrosare from chlor- oxuon, cycluron, diifox and thiram in the presence of nitrite. Mutation Res., 38, 136-137

Eisenrand, G., Ungerer, O. & Preussm, R. (1974a) Rapid forrtion of carcinogenic N-nitrosares by interaction of nitrite with fungicides deri ved frorn dithiocarbac acid in vi tro under simulated gast.ric conditions and in vivo in the rat stomch. Fd Cosmet. ToxicoL., 12, 229-232

Eisenrand, G., Ungerer, O. & Preussm, R. (1974b) Forrtion of N-nitroso cOITunds from agricultural chercals and nitrite. ln: Boovski, P. & Walker, E. A., eds, N-Ni troso Corunds in the Envirorint, Lyon, IA (IA Scientific Pulications No. 9), pp. 71-74

Eisenbrand, G., Ungerer, O. & Preussm, R. (1975) The reaction of nitrite with pesticides. IL Formtion, che..cal properties and cacinogenic activity of the N-nitroso derivative of N-methyl-l-naphthyl cabamte (carbal). Fd Cosrnt. ToxicoL., 13, 365-367

30 Eisenbrand, G., Schr&lhl, D. & Preussr, R. (1976) Carcinogenicity in rats of high oral doses of N-nitrosocarbaryl, a nitrosated pesticide. Cacer Lett., l, 281-284

Elespur, R.K. & Lijinsky, W. (1973) The formtion of carcinogenic nitroso compuns f~om nitrite and sorn typs of agricultural chercals. Fd Cosret. Toxicol., 11, 807-817 Epstein, S.S. & Legator, M.S. (1971) The J'utagenicity of Pesticides - Concepts and Evaluation, Camridge, .Mass., HIT Press

Go1brg, L., ed. (1974) Cacinogenicity Testing of Chcals, Cleveland, Ohio, Chercal Rubber Co.

Hall, H.K.1 Jr & Lueck, C.H. (1963) The ionization rnchaisn for the hydrlysis of acyl chlorides. J. org. Chem., 28, 2818-2825

Harris, P.N., Gibson, W.R. & Dillard, R.D. (1969) PlurifXtent oncogenicity of 1,1-diphenyl-2-propynyl N-cyclohexylcarbate. 1. Pro. Am. Ass. Cancer Res., 10, 35

Harris, P.N., Gibson, W.R. & Dillard, R.D. (1970) The oncogenicity of two l, 1 -diar 1 - 2-propyny 1 N-cycloalky lcarbates . Cacer Res., 30, 2952-2954 Harris, P.N., Gibson, W.R. & Dillard, R.D. (1972) Oncogenicity of 1- (4- chlorophenyl) - 1 -phenyl -2-propynyl carbaite for rats. ToxicoL. appL. Pharcol., 21, 414-418 von Hey, W., Thiess, A.M. & Zeller, H. (1974) Zur Prage etwaiger (',esundheits- schädigugen bei der Herstellung und Verarbeitul1g von Dimthylcarbamn- säurechlorid. ZbL. Arbeitsr., 24, 71-77

Hodge, H.C., Maynard, E.A., Das, W.L., Coye, R.D., Jr & Steadm, L.T. (1956) Chonic oral toxicity of ferric djJlthyldit.hiocarbarnate (ferham) and zinc dimthy ldi thocarbate (zirar). J. Pha£Bcol. exp. Ther., 118, 174-181

Hodgson, J.R., Hoch, J.C., Castles, T.R., Helton, D.O. & Le, C.-C. (1975) Metalism and disposition of ferba in the rat. ToxicoL. appL. Pharcol., 33, 505-513

IA (1974) IA Monogaphs on the Evaluation of Cacinogenic Risk of Chercals to Ma, 7.-, So Anti-thyroid and Related Substances, Nitro- furans and Industrial Chercals, Lyon, pp. 23-26, 45-52

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrucelli, L., Fislibin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Falk, B.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chercals for tllrigenici ty in mice: a prelirnar note. J. nat. Cancer Inst., 42,1101-1114

31 Kornova, A.A. & ZOtkina, V.P. (1971) On the u.se of electromyogaphy and certain indices of acety lcholine netalisr in evaluating the heal th status of workers engaged in the prcruction of zirar. Gig. Tr. Prof. Zabl., 15, 17-20

Kuh, R.J. & Ibrough, H.vv. (1976) Carbate Insecticides: Cherstry, Biocherstr and Toxicolog, Cleveland, Oho, C'nernical Rubber Co.

Leeling, N.C. & Casida, J.E. (1966) Metalites of cabal (l-naphthyl- N-rnthylcabate) in nils and enzymatic system for their fonntion. J. agric. Fd Chem., 14, 281-290

Lijinsky, W. & Taylor, H.W. (1976) Carcinogenesis in Sprague-Dawley rats by N-nitroso-N-alklcarbate esters. Cacer Lett., l, 275-279 Lijinsky, W., Conrad, E. & Van de Boart, R. (1972) Cacinogenic nirrosarnes form by drg/nitrite interactions. Nature (Land.), 239, 165-167

Loke, R.K. (1972) Thn-layer chr0ftography of l-naphthyl-N-hydroxy-N- rnthyl carbate and its application in two in vitro studies involving carbal. J. agric. Fd Chem., 20, 1078-1080 van Loten, M.J. (1972) De Dithiocarbaat-Alcohol-Reactie bij de Rat, Terborg, The Netherlands, Bedrijf FA. Lars Mirvish, S.S. (1975) Formtion of N-nitroso cornunds: chemstr, kinetics and in vivo occurence. Toxicol. appl. Pharmcol., 31, 325- 351

NCI (National Cancer Institute) (1975) Guidelines for Cacinogen Bioassay in Small Roents, V'¡ashington DC, US Departrt of Health, Education and Welfare

NTIS (National Techncal Informtion Service) (1968) Evluation of Carcino- genic, Teratogenic and Mutagenic Activities of Selected Pe.sticiÔes and Industrial Chemicals, VoL. l, Cacinogenic Study, i"¡ashington IX, US Depatrnt of Conmrce CDnnth, E.S. & Casida, J .E. (1966) Ivi2tallites of rrthyl- and dirthyl- carbate insecticide chercals a.s fonr by rat li ver microsones. Bull. environr. Contar. Toxicol., l, 59-69 Pestava, A.G. (1966) Toxicityof diptal and avadex. Gig. ToksikoL. Pestits. Klin. Otvlenii, 4, 166-169 Phillips, W.E.J. (1968) Chges in the nitrate and nitrite contents of fresh and processed spinach during storage. J. agric. Fd Chein., 16, 88-91

Plewa, M.J. & Getile, J.M. (1975) A mize-microbe bioassay for the detection of proxima.l mutagenici ty of agricul tural chercals. .laize C::et. Coop. News1ett., 49, 40-43

32 Plewa, M.J. & Gentile, J.H. (1976) Hutagenicityof atrazine: a maize- microbe bioassay. Mutation Res., 38, 287-292 Quarles, J.M. & Tennt, R.vv. (1975) Effects of nitrosocarbaryl on BA/3T3 cells. Cancer Res., 35, 2637-2645

Queen, A. (1967) Kinetics of the hydrolysis of acyl chlorides in pure water. Caad. J. Chem., 45, 1619-1629

Richardson, E.M. & Batteese, R.I., Jr (1973) An incident of zectran poisoning. J. Maine me. Ass., 64, 158-159

Ryazanova, R.A., Druzhinina, V.A. & Nevstrueva, V.V. (1972) Exprjnental data for substatiating the maum perrssible concentration of zineb in the air of working prerses. Gig. i Sanit., 50, 42-45

Seidler, H., H.itig, M., Schnaak, W. & Engst, R. (1970) Untersuchungen ül~r den Metalisrus einiger Insektizide und Fungizic1e in der Ra.tte. II. Verteilung und Abbau von 1 4C-markiertem ~'Jaeb. Die Nahrug, 14, 363-373

Sen, N.P., Donaldson, B.A. & Chrbonneau, C. (1974) Formtion of nitroso- dimthylare fram the interaction of certain pesticides and nitrite. ln: Bogovski, P. & Walker, E.A., eds, N-Nitroso Cooounds in the Environrnt, Lyon, IA (IA Scientific PulicationS No. 9) / pp. 75-79

Stecher, P.G., ed. (1968) Th lv1erck Index, 8th ed., Raway, NJ, ~'1erck & Co.

Str&i, J.H. (1965) Metalism of disulfiram and diethyldithocarbate in rats with demnstration of an in vivo ethanol-induced iriibition of the glucuonic acid conjugation of the thiol. Biochem. Phanna.col., 14, 393-410 Sullivan, L.J., Eldridge, J.H., Knak, J.B. & Ta1lant, H-J. (1972) 5,6-Di- hydro-5,6-dihydroxycarbarl glucuonide as a significant ~tablite of carbal in the rat. J. agric. Fd Che., 20, 980-985 Tanenbum, S.R., Sinskey, A.J., Weisr, M. & Bishop, vJ. (1974) Nitrite in hum saliva. Its possible relationship ta nitrosarne formtion. J. nat. Cancer Inst., 53, 79-84

Truut, R., Fujita, M., Lich, N.P. & Chaigneau, M. (1973) Etude des trans- formtions métaliques du zjnèbe (éthylène bisdithiocarbamate de zinc) chez le rat. C.R. Acad. Sei. (Paris), 276, 229-233

Ungerer, O., Eisenbrand, G. & Preussm, R. (1974) Zur Reation von Nitrit mit Pestiziden. Bildung, chersche EigpJlschaften und cancerogene Wirkung der N-Nitrosoverbindung des Herbizids fi-f''lthyl-fi'- (2-benzothiazolyl)- Hastoff (Benzthazuron). Z. Krebsforsch., 81, 217-224

33 Van Duuren, B.L., Goldschmidt, B.M., Katz, C. & Seidmn, 1. (1972) Dinithyl- cabayl chloride, a rmltipotential carcinogen. J. nat. Cacer Inst., 48, 1539-1541

Watts, R.R., Storherr, R.W. & Onley, J.H. (1974) Effects of coking on ethylenebisdith.ocarbate degradation to ethylene thiourea. BulL. envirorn. Conta. Toxicol., 12, 224-226

Weisburger, E.K., Ulland, B.M., Schueler, R.L., Weisburger, J.H. & Harris, P.N. (1975) Cacinogenicity of thee dose levels of 1,4-bis (4-fluorophenyl)- 2-propynyl-N-cyclootyl cabate in male Sprague-Dawley and F344 rats. J. nat. Cancer Inst., 54, 975-979

WHO (1974) 1973 Evaluations of sor resticide residues in foo. v-vd Hlth Org. Pest. Res. Ser., No. 3, pp. 141-176

34 TH IDN(xRAHS CAR.YL

1. Chercal and Physical Data 1.1 Synonym and trade nas

Chem. Abstr. Reg. Serial No.: 63-25-2 Cher. Abstr. Nam: M2thylcarbate l-naphthalenol Methy lcabate 1 -naphthol; nethy lcabac acid, 1 -naphthy 1 ester; N-rnthy lcabac acid, 1 -naphthy 1 ester; N-rnthy 1 - 1 -naphthy 1 carbate; N-rnthyl -a-naphthylcarbate; N-rnthyl -a-naphthylurethan; 1 -naphthol N-rnthy lcabarte; 1 -naphthy 1 rrthy lcarbate; 1 -naphthy 1 N-rnthy 1 carbate; a-naphthy l-N-rnthy lcarbate

Arlam; Atoxa; Caprolin; Cabatox; Carbatox-60; Carbatox 75; Carplin; Cornund 7744; DenapJn; Dicarba; r:,anil; C:i' s; Hexvin ; Kabaspray; Karbatax; Kabosep; NAC; Panam; Ravyon; Septene; Seviil; Sevin; Tricaram; OC 7744; Union Cabide 7, 744

1. 2 Chercal formla and lTlecular weight

o Il CH3 O-C-N.. 00 'H C12Hii N)2 M'I. wt: 201.2 1.3 Chercal and physical properties of the substance

From Stecher (1968), llîless otherwise speified

(a) Description: Crystals

(b) Melting-point: l450C

(d) Volatility: Vapeur pressure is .c0.005 rr at 260C (Frear, 1963).

37 (e) Stability: Stale ta light and heat UP to 700C (Frear, 1963); hydrol ysed rapidl y by alkalis 1.4 Techncal products and iruri ties Cabal is available in the us and Japan as a technical grade product containing at least 99% of the cornund. A paially formlated, finely ground grade of 95% purity is available in the US for use in the maufacture of rrre dilute, solid formulations. Formulations of carbarl for various uses include v.ttale poers, dusts, granular products, suspesions, erulsifiable concentrate solutions and bai t formlations (von Ruer et al., 1974).

2. Production, Use, Occurence and Analysis

For imrtant background informtion on this section, see preamle, p. 15.

2.1 Production and use Carba 1 can be synthesized by reacting phosgene wi th 1 -naphthol , follOWed by reaction with rnthylarne (Larech, 1959). Bath this rrthcx and the reaction of l-naphthol with nethyl isocante can be used for its ccmrcial production (von Rurer et al., 1974); the latter is believed to be used curently in the US. Conncial production of carbaryl ln the us was first reported in 1960 (US Tariff Comnssion, 1961). ln 1972, US production was reported to be 24 million kg, of which 12.7 million kg ~re exrted (von Ruer et aL., 1974) .

It 1S estimted that abut 5-10 million kg cabal are produced in the Feder Repulic of Gei:y anualy. Teclcal grade carbal is mt prod-oed in Japa; anual imrts during the period 1970-74 averaged 1. 04 million kg, with a pe of 1.17 million kg in 1971. Atut 200 thousar kg cai:ryl, presum1y in fonnte fonn, were exrtd fro Japan in 1974 (Japanse Mistr of Agricuture an Forestr, 1975).

The major use for carbal 1S as a broad sptru inecJcicide, but it is also registered in the us as an acaricide and mlluscicide. It is used

38 for the control of insec-ts which attack fruits, vegetales, cotton, tobacco, corn, rice, sugar bets, animls and livestock, and ornarntal trees and shrs (US Environrtal Protection Agency, 1972). Abut 0.6 million kg are used anuall y in l tal Y . A.rdirY ta th US Ocationa Saety am Helth Adnistration health stads for air contanants, an enloyee' s exsure ta carbal should not exceed a tiIeighted average of 5 mg/m 3 in the workplace air during any eight-hour work shift (US Code of Federal Regations, 1975). ln the USSR, the maum allowable concentration in WJrking atnspheres is 1 rn/m3 (Winell, 1975).

Residue tolerances on raw agricul tural cormi ties have ben estalished in the US (US Code of Federal Reglations, 1974). Recommnded tolerances were also estalished at the Joint Meting of the FAO Working Party of Exrts on Pesticide Residues and by the WHO Exrt Cæi ttee on Pesticide Residues in Deerr 1973; at the sar tim these two groups established an acceptale daily intake of carbaryl for man of 0-0.01 mg/kg bw (v\l, 1974). 2. 2 Occurence Caba 1 is not know to occu as a na tural product. ln a continuig program invol ving the rrni toring of pesticide residues in fcx, the US Depatmt of Health, Education and Welfare found an increasing level of carbaryl in foo sarles collected at retail outlets during the period 1968-71. Betwen June 1970 and April 1971, carbal was found in leafy,legu and root vegetales, and in garden and tree fruts. Of 270 cOI1site foo sarles exned, cabal was found in 20; in 15 of these it was found only at trace levels (Manske & Corneliussen, 1974). 2 . 3 Anal ysis

The Association of Official Anlytical Chests (Horwitz, 1975) has issued stadad rnthods for carbal analysis, including a colorirtric ræthod in which para-nitrobnzenediazonium fluoborate is used as a colour reagent; the develope colour is read sptrophotonetrically. A rrification of ths rnthod has be describ (Kurtz & Studholm, 1974). McDe:itt (1973, 1975) reported rrifications to the extraction technique

39 of an earlier AOAC rnthod. A procedure involving extraction and hydrolysis followed by the addition of ortho-toluidine had a sensitivity of 0.1-1 Wg/ 20 mg sarle (Ragaswar & Majurer, 1974).

Colur chromtography has reen usd ta separate carbartes, such as carbal, which are then identified by thin- layer chrortography (Lichtenbrg, 1975) or by gas chromtography and electron-capture detection after derivatization (Sherr & Shafik, 1975). The sensitivity of the laJcJcer rrthod ailowed detection of 40-2000 ng.

Weyer (1974) developed a gas-liquid chromatogaphic rrthod for deterrning carbal directly in formlations. A high-pressure liquid chromatographic rnthod for deterrning carbarl at arient teratures had a reported sensitivity of greater th 7 ng (Colvin et al., 1974). By the use of direct gas chromtography coupled wi th an alkali flai detector, recoveries of 90-100% over a range of 4-2000 ng have been reported (Lorah & Hemhill, 1974).

Thin- layer chromtography has been used ta deterrne the carbary 1 content of biological sarles: after extraction and hydrolysis, the coloured cornunds from the resul ting l-naphtlìol were applied to thin- layer plates; as litt1e as 0.01 Wg carbaryl could be detected (Malinin, 1974) .

A water rrni toring system for cholinesterase inhibi tors, including, but not specific for, carbal, uses an electrochercal cell which rrasures changes in the activity of imbilized enzyms (Goson & Jacobs, 1972).

3. Biological Data Relevant to the Evaluation of Carcinogenic Risk ta Ma

3.1 Carcinogenici ty and related studies in animls

(a) Oral admnistration

Mouse: Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F nuce and 1 18 male and 18 femle (CS7BL/6xA) F mice received commrcial carbarl 1 (m.p. l4l-l420c) according to the follawing schedule: 4.64 mg!kg hv in gelatine at 7 days of age by stornch tub and the sam arunt (not adjusted

40 for increasing boy weight) daily up to 4 ~eks of age¡ subseqently, the mice were given 14 mg carbaryl per kg of diet. The dose was the maxi tolerated dose for infant a. young mice but not necessaril y sa for adul ts . The exprimt was terrated when the anÌIls were abut 78 v.s of age, at which tim 16, 18, 17 and 18 rrce in the four groups, respecti vel y, were still ali ve . Tuur incidences were conped wi th those ooserved aTng 79-90 necropsied mice of each sex and strain, which either had æen untreated or had received gelatine on1y: the incidences v.re not significantly greater (P~O. 05) for any turur typ in any sex-strain subroup or in the combined sexes of either strain (Il1neS et al., 1969¡ NTIS, 1968).

Rat: Of 60 random-bred rats given 30 rr/kg bN cornrcial carbaryl (97.7% pure) in water by stomach tub daily for up to 22 IInths, 12 surivors were exared: 3 had fibrosarcors, and 1 had an osteosarcom. One fibrosarcor occurred amng 46 untreated controls which suri ved 22 rrnths (Andrianova & Alekseev, 1970) (P.(O.Ol).

Groups of 20 male and 20 femle CF-N rats v.re fed diets containing o (control), 0.005 (2 mg/kg l:/day), 0.01 (4 rr!kg l:/day), 0.02 (8 rn/kg bw/day) or 0.04% (16 rn!kg l:/day) carbarl¡ surivors were killed after 732-736 days. The ITan ages at death for :tth sexes at the 0.04 and 0.02% levels were 656 and 630 days, and that for contro1s, 585 days. The incidence of tururs in carbal-treated rats was no different from that in controls¡ turur typs were not reported (Carnter et aL., 1961).

(b) Subcutaneous admnistration

Mouse: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F mice and 1 18 male and 18 femle (C57BL/6xA)F mice v.re given single s.c. injections 1 of 100 rr!kg bN camrcial carbal (m.p. l4l-l420C) in dithyl sulphoxide on the 28th day of life and were observed until they were alut 78 \Meks of age, a t which tim 15, 18, 18 and 17 rrce in the four groups, res¡:cti ve1 y, were still ali ve. Tuur incidences were coIlared wi th those in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls D1at were necropsied. Incidences were not significant1y increased (P~0.05) for any turur typ in any sex-strain subroup or in the combinecl sexes of ei ther strain (NTIS, 1968) (The Working Group noted that a negative result obtained

41 after a single s.c. injection may not be an adegate basis for discounting carcinogenici ty J . Groups of 30 3-rrnth old male A/Jax or C3H rnce \Mre given s .c. injections weekly over 5 rrnths of 10 rr/anirl carbal in 0.2 ml agar suspesion, the agar suspension alone or left untreated. The minibr of lung tururs seen at 8 rrnths of age was no greater in treated than in control rnce (Carnter et al., 1961).

Rat: Of 48 random-bred rats glven a s.c. imlant of 20 rr/kg conircial carbal (97.7% pure) in a 250 rr paaffin pellet, 10 surived 22 rnnths; 2 had subtaeous sarcoms at the site of irlantation. One filrosarca occurred arng 46 controls, which did not receive paaffin pellets and were still alive at 22 rnnth (Andrianva & Alekseev, 1970) (p:?0.05J. (c) Intraperitoneal admistration

!-use: Of 16 7-9-vek old male A/He mice given 12 Lp. injections of carbaryl (purity not given) in tricaprylin over 4 weeks (total dose, 6 rr/ animl), 6 out of 15 mice still alive 20 \Meks after the end of the treatrnt and then killed develope lung tururs. Of tricaprylin-injected controls, 7/28 animls developed a total of 8 lung tuiurs; 2/31 untreated controls ha 1 lung turur each (Shiin et al., 1969) (P:?0.05J.

3.2 oter relevant biological data

(a) Exrimental system

The oral ID for carbal ln rmce ls 438 rr/kg l: (Rybakova, 1966). 50 Oral ID 's in rats, femle rats and rabbits are 510, 610 and 710 rr/kg b,, 50 respeti vel y (Carpnter et al., 1961).

No toxic effects \Mre seen in rats adrnistered up to 200 rr carbal per kg of diet for 2 years. With higher dietary levels (1500 and 2250 rn/kg of diet), diffuse, cloudy swlling of the kidney tubules was seen after 96 days (Carpter et al., 1961).

Neurotoxicological effects of cabal (200 rr/kg of diet/day for 50 days) have been shaw in Wista rats (i) to affect lean1Ìng (after 25 days) and performce (after 15 days), (ii) to affect electroecephalographic patterns under resting and light-stirUiated conditions, and (iii) to inhilit

42 acetylcholinesterase activity in the eroces and in various pas of the brain. Mild but perment and increasing functional deviations of the central nervous system were found (Dési et al., 1974). Maked functional and strctural changes of the pituita gland with iminrnt of thyroid and gonadal function have been found in rats adristered 7, 14 or 70 mg carbaljkg bw/day for up ta 12 rrnths (Shtenrg & Ryakova, 1968).

Of an oral dose of (1-naphthyi-i-14C)-N-methylcarbate give to rats, 53% an 82% were absorbed after 20 mi and 1 hour, respetively (Caspe et aL., 1973). Carbal is absorbed very rapidly from the lung, 2.5 tis faster than from the small intestine (Hwag & Schaner, 1974). The distribution of carba l, 1 4 C- lablled at various r:si tions, was investigated by Knaak et al. (1965) in rats an gune-pigs an by Krishna & Casida (1966) in rats. The relatively lon:er retention of l4C after oral admistration of (N-nethyi-14C)-cabaryl may indicate rnthylcarbaylation of proteins in vivo after cabal hydrolysis (Strother ,1972) ; 25% of the carbate ester was hydrolysed (Kuh & Dorough, 1976), and the l-naphthl produced was rapidly excreted. Excretions of carba 1 after enteral and parenteral admnistrations were sirlar . Carbal (1) (Schem 1) was netalized by rat liver microsors ta l-naphthyl-N-hydroxythylcarbate (2), 4-hydroxy-l-naphthyl-N-methylcarbate (3), 5-hydroxy-l-naphthyl-N-methylcarbate (4) and 5,6-diliydroxy- 5,6-dihydro-l-naphthyl-N-methylcarbate (5) (Dorough & Casida, 1964; Dorough et al., 1963; Hassan et al., 1966; Kuh & Dorough, 1976). Hum and rat liver honenates produced eql arunts (3.4%) of the 4- and 5-hydroxy derivatives (3) and (4) when incute with cabaryl, although much of the parent canund (72 and 58%, respectively) was recvered unchanged; rrre l-naphthyl-N-hydroxythylcarbate was forr by rat liver (4%) th by hur liver (~l%) (Matsumura & Ward, 1966; Strother, 1970, 1972). Hydrlytic products included 1 -naphthol (6) (Dorough & Caida, 1964).

Epxidation is imlicit fram the identification of comunds (3), (4) and (5) (Bend et aL., 1971). AIng the netalites found in the urine of

te treated rats wee the rnrcapturic acids S- (4-hydroxy-l-naphthyl) cys ine (7) and S- (5-hydroxy-l-naphthyl)cysteine (9) (Bed et aL., 1971) and the 43 .i

SCHE i ~NCH 20H 00. 00 o o CI Il ~~~~~CH'Il (l

SCH2-CHC02H SCH2-CHC02H cg;~~ NH21 l NHCOCH31 NHCOCH31 1 NH2 ~OrO ~ o 0l SCHi-CHC02HQ) SCH2-CHC02H ~ OCNCHIl 3 IlOCNCH 3 _ ~CH'IL _ ~CH' Il 1- 1 1 10 '-o 10 + 9CNCH,Il L IlOCNCH, +Il OC~CH, CI '\'"oloJ J/ 0cQH ~~ ~ HO OH C! (j CD glucuonide of (5) (Sullivan et aL., 1972). Another netallite, l-naphthyl- N-hydroxy-N-rnthylcarbate (11), has been identified in rat-liver preparations incubted with carbal (Loke, 1972). Carund (5) has been identified as a rnta1ite in bovine milk (Baon et al., 1969), and (1), (2), (3) and (6) have ben foun in srller quantities (Cam et al., 1963; Dorough, 1967; Whitehurst et al., 1963).

Cress & Strother (1974) have shov that carbarl induces microsoiml hepatic rned-function oxidase in mice.

Ingestion of carbarl by beagle dogs thoughout gestation caused teratogenic effects at all but the lowest dose level (3.125 rn!kg l:/day). Emryopathes in 21 out of a total of 181 pups \\re characterized by abcrnal -thoracic fissures wi th vaing degrees of brachygnathia, ecaudate pups, failure of skeletal formtion and superfluous phalanges (Srnlley et al., 1968). Carbal was teratogenic in gunea-pigs when admistered during organogenesis at 300 rn!kg tw/day, but not in haters (at 250 rn!kg tw) or in rabbits (at 200 rr!kg tw) (Robens, 1969). No effects on reproduction occurred in rats gi ven 200 rr!kg tw dail y in the diet, but reduced fertility was seen in those given 100 rn!kg tw daily intragastrically (Weil et al., 1972).

The reaction of carbar 1 wi th ni trous acid 1eads to forntion of N-ni tro- socarbal (Elespur & Lijinsky, 1973). Ths proceeds 1ess readily at lower concentrations (Eisenbrand et aL., 1975), but formtion of N-nitrosocrbaryl in the stomach could be expcted. N-Nitrosobarl, withut rntalxÜic activation, is a potent bacterial mutagen (Elespur et aL., 1974; Lijinsky & Elespur, 1976) and is mutagenic in yeast (Siebrt & Eisenbrand, 1974). It is carcinogenic in rats after its oral admistration (Eisenbrand et al., 1976; Lijinsky & Taylor, 1976) and after single subutaeous injections (Eisenbrand et aL., 1975). N-Nitrosocrbal interacts with hum DNA in vitro, proucing alkali-sensitive bonds (Regan et al., 1976). These authors also found that, in contrast to its N-nitroso derivative, (rntl1yi-14Cl-carbaryl did not bind to the DNA of hur skin cells from norml subjects or from those with xeroderm pigmntosum.

45 Carbal inhibits spindle fibre forntion in plants (Arr, 1965; Amr & Farah, 1968; Wuu & Grant, 1966). Inhibition of mitosis and spindle fibre formtion has also been reported in cultured hum emryonic fibroblasts after treatmt with 20-80 ~g/rn of a technical product containing 84% carbarl

(Vasilos et al., 1972).

No reverse mutations were observed in a spot test on Escherichia coli (Ashw-SmH:h et aL., 1972), and no mitotic gene conversion was seen ln Saccharomyces cerevisiae (Siebrt & Eisenbrand, 1974); rntablic activation system were not used in these tests. ln the presence of an Aroclor- induced, rat-liver micros0fl prepaation carbal was not mutagenic to TAlOO, TA98, TAl535 or TAl537 strains of Salmonella typhimurium (McCa et al., 1975). Cabarl (85% purity) caused an increased numr of recessive lethals ln Drosophila melanogaster (Brzeskij & Vaskov, 1971). No increase of domiant lethals in mice was recorded after five oral treatrnts with 50 or 1000 ir!kg (Epstein et al., 1972). ln a dcrant lethal test in nile rats fed up to 200 ir!kg cabal per day in the diet or up to 100 m:!kg pe day by oral intubation until 224 days of age, no increase in dominant lethality could be estalished (Weil et al., 1973) (Th data is difficult to evaluate since results are given as the percentage of pregnan.t ferles with one or more foetal deaths, and th actual freqenc-y of live or dead foetuses is not givenJ.

(b) Ma

Workers engaged ln the production, collection and bagging of carbaryl were exsed by inalation to O. 23- 31 ir dust/m 3 ; they excreted up to 80 ir l-naphthol/day but shcwed only slight depression of bloo acetylcholinesterase activity (Best & Muray, 1962).

A large proportion of carba 1 applied to the forear of hil volunteers was absorbed, and 74% of the dose was excreted in the urine (Feldm & Maibach, 1974).

The urinar rntalites in hurs who ingested carbaryl included the glucuonides of (3) (Scher 1) and (6) (Knak et al., 1968). The rntablic activity of hum organ cultures in vitro was ln the order liver?lungs?

46 kidneys;.placenta;.vaginal rncosa;.uteru and uterine leioI1orn (Chin et al., 1974). Hum liver microsornl prepaations gave the 4- and 5-hydroxy derivatives (3) and (4) when incubted with carbaryl, although 72% of the paent cornund was recovered unchanged (Strother, 1972). Hum volunteers who ingested 0.12 mg/kg l: carbaryl/day for 6 weeks showed a decrease in the ratio of amo acid:creatiniri nitien in the urine (wills et al., 1968). 3. 3 Case reports and epiderological studies

No data were available ta the Working Group.

4. Connnts on Data Reported and Evaluation 4. 1 Animl data

ln one study in rats with relatively low surival rates, carbaryl produced sarcos following i-ts oral but not after its subtaneous admnistration. ln one study in mice by oral admnistration, no carcinogenic effect was observed. The available data not not allow an evaluation of the carcinogenici ty of carba 1 to be made. Carba 1 can react wi th ni tri te under mildl y acid candi tions , sirulating those in the hur stornch, to give rise to N-nitrosocarbaryl, which has been shaw to be carcinogenic in rats (see also 'General Remrks on Cabartes, Thiocarbartes and Carbazides' , pp. 25-27). 4.2 Hur data

No case reports or epiderological studies ~re available ta the Working Group.

47 5. References

Arr, S.M. (1965) Cytological effects of pesticides. 1. Mitotic effects of N-methyl-l-naphthyl carbate 'Sevin'. Cyologia, 30, 175-181

Arr, S.M. & Farah, O.R. (1968) Cyological effects of pesticides. III. Meiotic effects of N-rnthyl-l-naphthyl carbate 'Sevin'. Cylogia, 33, 337-344

Andrianova, M.M. & Alekseev, LV. (1970) On the carcinogenic properties of the pesticides sevine, maeb, cirar and cineb. Vop. Pitan.i 29, 71-74

Ashwoc-Smith, M.J., Trevino, J. & Ring, R. (1972) Mutagenicity of dich- lorvos. Nature (Lond.), 240, 418-420

Baron, R.L., Sphon, J.A., Chen, J.T., Lustig, E., Doherty, J.D., Hasen, E.A. & Kolbye, S.M. (1969) Confirmtory isolation and identification of a metalite of carbarl in urine and milk. J. agric. Fd Chem., 17, 883-887

Bend, J.R., Holder, G.M., Protos, E. & Ryan, A..T. (1971) Water-soluble metali tes of carbary 1 (1 -naphthy 1 N-rnthy lcarbamate) in TIuse- li ver preparations and in the rat. Austr. J. biol. Sci., 24, 535-546 Best, E.M., Jr & Muray, B.L. (1962) Obserations on v.rkers exsed ta sevin insecticide: a prelirnar report. J. occup. M.., !, 507-517

Brzeskij, V. V. & Vaskov, V. 1. (1971) Mutationsuntersuchungen und Fertili- tätsberechnung bei Drosophila melanogaster unter Carbarylwirkung. Angew. Parasitol., 13, 23-28

Cam, H.B., Buttrar, J.R., Hays, K.L. & Arur, B.W. (1963) Sevin residues in milk from dairy CCMS follCMing dennl applications. J. econ. Entorrl., 56, 402-404

Carpenter, C.P., Weil, C.S., Palm, P.E., Wocside, M.W., Nair, J.H., III & Smyth, H.F., Jr (1961) Malian toxicity of l-naphtl1yl-N-rnthylcarbate (sevin insecticide). J. agric. Fd Ch., 9, 30-39

Casper, H.H., Pekas, J.C. & Dinusson, h'.E. (1973) C..stric absorption of a pesticide (l-naphthyl N-rnthylcarbamte) in the fasted rat. Pest. Biochem. Physiol., l, 391-396

Chin, B.H., Eldridge, LT.M. & Sullivan, L.J. (1974) Metablism of c;:rbaryl by selected hUIn tissues using an organ-rnintenil1ce techni(JUe. Clin. Toxicol., 7, 37-56

Colvin, B.M., Engdahl, B.S. & Hans, A.R. (1974) Determina tion of carbaryl in pesticide fonnulations and fertilizers by high-pressure liqud chromatography. J. Ass. off. analyt. Chem., 57, 648-652

48 Cress, C.R. & Strotl1er, A. (1974) Effects on drug netalisr of carbarl and 1 -naphthol in the muse. Life Sci., 14, 861-872

Dési, 1., Gönczi, L., Simn, G., Farkas, 1. & Kneffel, Z. (1974) Neurotoxi- cological studies of two carbate pesticides in subacute animl expri- rnnts. ToxicoL. appL. PhacoL., 27, 465-476

Dorough, H.W. (1967) Carbarl-C14 netallism in a lactating CC. J. agric. Fd Cher., 15, 261-266

Dorough, H.W. & Casida, J .E. (1964) Nature of certain carbamte rntabolites of the insecticide sevin. J. agric. Fd Chem., 12, 294-304

Dorough, H.W., Ieeling, N.C. & Casida, J.E. (1963) Non-hydrolytic paUiway in rntalisr of N-rnthylcarbate insecticides. Science, 140, 170-171

Eisenbrand, G., Ungerer, O. & Preussm, R. (1975) The reaction of nitrite with pesticides. IL Formtion, chercal properties and carcinogenic activity of the N-nitroso derivative of N-rnthyl-l-naphtliyl carbate (carbaryl). Fd Cosret. Toxicol., 13, 365-367 Eisenbrand, G., Schrl, D. & Preussm, R. (1976) Carcinogenicity in rats of high oral doses of N-nitrosocarbaryl, a nitrosated pesticide. Cancer Lett., l, 281-284

Elespuru, R.K. & Lijinsky, W. (1973) The formtion of carcinogenic nitroso cornunds fror ni tri te and sorn tys of agricul tural chercals. Fd Cosrt. Toxicol., 11, 807-817

Elespur, R.K., Lijinsky, W. & Setlow, J.K. (1974) Nitrosocarbarl as a patent mutagen of environrntal significance. Nature (Lond.), 247, 386-387

Epstein, S.S., Arold, E., Andrea, J., Bass, W. & Bishop, Y. (1972) Detec- tion of chercal mutagens by the domiant lethal assay in tl1e muse. ToxicoL. appL. PharrcoL., 23, 288-325

Feldr, R.J. & Maibach, H.I. (1974) Percutaneous peetration of sarr pesticides and herbicides in ma. Toxicol. appl. Pharcol., 28, 126- 132

Frear, D.E.H., ed. (1963) Pesticide Index, State College, Pensylvania, College Science Publishers, p. 47 Goson, L.H. & Jacobs, W.B. (1972) Rapid Detection System for Organo- phosphates and Carbarte Insecticides in Water, EPA-R2-72-0l0, Washington DC, us Envirorrntal Protection Agency

Hassan, A., Zayed, S.M.A.D. & Alel-Hard, F.M. (1966) Metablism of carbate drugs. 1. Metal-ulism of l-naphthyl-N-rnthyl carbate (sevin) in the rat. Biocher. Pharcol., 15, 2045-2055

49 Horwitz, W., ed. (1975) Official Methods of Anlysis, 12th ed., Washington DC, Association of Official Analytical Chersts, pp. 537-539

Hwang, S.W. & Schaner, L.S. (1974) Absorption of carbary 1 from the lung and srll intestine of the rat. Environr. Res., 7, 206-211

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrucelli, L., Fishbin, L., Hat, E.R., Pallotta, A.J., Bates, R.R., Falk, B.L., Gart, J.iJ., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemicals for turrigenici ty in mice: a prelirnar note. J. nat. Cancer Inst., 42, 1101-1114

Japanese Ministry of Agriculture and Forestry (1975) Noyaku Yoran (A.gri- cultural Chemicals Anual), 1975, Division of Plant Disease Prevention, Tokyo, Takeo Endo, pp. 85, 93, 224, 225

Knaak, J.B., Tallant, M.J., Batley, W.J. & Sullivan, L.J. (1965) The rntalisr of carbary 1 in the rat, gunea pig and ma. J. agric. Fd Chem., 13, 537-543

Knaak, J.B., Tallant, M.J., Kozbelt, S.J. & Sullivan, L.J. (1968) The rntalisr of carbal in ma, rrnkey, pig and sheep. J. agric. Fd Chem., 16, 465-470

Krishna, J.G. & Casida, J.E. (1966) Fate in rats of the radiocarbon from ten variously lablled rnthyl- and dithy 1 -cabama__te- 1 1+ C insecticide chemcals and their hydrol ysis products. J. agric. Fd Chem., 14, 98- 105

Kuh, R.J. & Dorough H.W. (1976) Carbate Insecticides: Cherstr, Bio- cherstry and Toxicolog, Cleveland, Ohio, Chemical Ruber Co., p. 109 Kurtz, D.A. & Studholi, C¿. (1974) Recovery of trichlorfon (Dylox (8) and carbarl (Sevin Q3) in songbirds following spraying of forest for gysy rrth. BulL. environr. Contar. ToxicoL., 11, 78-84 Larech, J .A. (1959) a-Naphthol bicyclic arl esters of N-substituted carbac acids, US Patent 2, 903, 478, Septerr 8, to Union Carbide

Lichtenbrg, J.J. (1975) Methods for the deterrnation of spcific organic pollutats in water and waste water. Inst. Electrical Electronics Engineers Trans. Nuclear Sci., NS-22, 874-891

Lijinsky, W. & Elespur, R.K. (1976) Mutagenicity and carcinogenicity of N-nitroso derivatives of carbate insecticides. ln: Rosenfeld, C. & Davis, W., eds, Enviromæntal Pollution and Carcinogenic Hisks, Lyon, IA (IA Scientific Pulications No. 13) (in press)

Lijinky, w. & Taylor, H.W. (1976) Carcinogenesis in Sprague-Daley rats by N-nitrosoN-alkylcabate esters. Cacer Lett., l, 275-279

50 Loke, R.K. (1972) Thin-layer chromtography of l-naphthyl N--hyòroxy-N- rnthylcabate and its application in two in vitro studies involving carbal. J. agric. Fd Chem., 20, 1078-1080

Lorah, E.J. & Hemhill, D.D. (1974) Direct chromtography of sor N-rnThyl- carbate pesticides. J. Ass. off. analyt. Ch., 57, 570-575 Malinin, O.A. (1974) Determation of sevin in biological specimns. Veterinariya (Moscow), ~, 104-105

Maske, D.D. & Corneliussen, P.E. (1974) Pesticide residues in total diet samles. VII. Pest. !-nit. J., §., 110-114 Matsura, F. & Ward, C. T. (1966) Deradation of insecticides by the hur and the rat liver. Arch. environr. Hlth, 13, 257-261

M.an, J., Choi, E., Yarsaki, E. & AIs, B.N. (1975) Detection of carcinogens as rntagens in the Sa lmone L lalmicrosorn test: assay of 300 chercals. Proc. nat. Acad. Sci. (Wash.), 72, 5135-5139

McDenrtt, W.H. (1973) Infrared anlysis of cabal insecticide: rrification of the extraction procedure to accorrate liquid suspension formulations. J. Ass. off. analyt. Chem., 56, 576-578 McDenrtt, W.H. (1975) Carbaryl insecticide: extraction froID dust and pcder forrations. J. Ass. off. analyt. Ch., 58,28-32

NTIS (National Technical Informtion Service) (1968) Evaluation of Carcino- genic, Teratogenic and Mutagenic Activities of Selected Pesticides and Industrial Chercals, Vol. l, Carcinogenic Study, Washington IX, US Depart of Corrce Ragaswam, J.R. & Majumer, S.K. (1974) Colorimtric rrtl10d for estimtion of carba 1 and i ts residues on grains. J. Ass. off. arlyt. Chan., 57, 592-594 Regan, J.D., Setlow, R.B., Francis, A.A. & Lijinsky, W. (1976) Nitroso- carbal: its effect on hur DNA. Mutation Res., 38, 293-302

Robens, J.F. (1969) Teratologic studies of cabaryl, diazinon, norea, disulfiram an thiram in srll la.ratory animIs. 'Ixicol. appl. Pharcol., 15, 152- 163 von Riner, R., Lawless, E.W. & Meiners, A.F. (1974) Production, Distribution, Use, and Environrntal Iract Potential of Selected Pesticides, Washington De, US Environrntal Protection Agency, pp. 133-136

Rybaova, M.N. (1966) On the toxic effect of sevine on anirls. Gig. i Sanit., 31, 42-47

Shern, J. & Shafik, T .M. (1975) A rnlticlass, mutiresidue analytical rnthod for deterrning pesticide residues in air. Arch. environr. Contam. Toxicol., 3, 55-71 51 Shimin, M.B., Wieder, R., McDonough, M., Fishbin, L. & S~rn, D. (1969) Lung tumr response in strain A rnce as a quantitative bioassay of carcinogenic acti vi ty of sorn cabartes and aziridines. Cancer Res., 29, 2184-2190

Shtenbrg, A.I. & Rybakova, M.N. (1968) Effect of carbarl on the neuro- endocrine system of rats. Fd Cosrnt. ToxicoL., 6, 461-467

Siebrt, D. & Eisenbrand, G. (1974) Induction of ITi totic gene conversion in SacchapOrTjj,:eD cerevc:,c;.,'ae by 0-ni trosated pesticides. Mutation Res., 22, 121-126

Srlley, H.E., Curtis, J.M. & Earl, F.L. (1968) Teratogenic action of carbal in beagle dogs. Toxicol. appl. Pharmcol., 13,392-403

Stecher, P .G., ed. (1968) The Merck Index, 8th ed., Rahway, NJ, Merck & Co., p. 104

Strother, A. (1970) Comprative metablism of selected H-metBylcarbartes by hum and rat liver fractions. Biochem. Pharmcol., 19, 2525-2529

Strother, A. (1972) Tn 7yUrO rntallism of methylcarbate insecticides by hum and rat liver fraction. ToxicoL. appL. PharmcoL., 21, 112- 129 Sullivan, L.J., Eldridge, J.M., Knaak, J.B. & Tallant, M.J. (1972) 5,6- Dihydro-5,6-dihydroxycarbaryl glucuronide as a significant rntablite of carbal in the rat. J. agric. Fd Cher., 20, 980-985

US Code of Federal Regulations (1974) Protection of Envirorint, Title 40, pat. 180.169, Washington De, US Goventmnt Printing Office, p. 262

US Code of Federal Regulations (1975) Air Contarnants, Title 29, part. 1910.1000, Washington De, US Goverrint Printing Office, pp. 59-60 us Environmntal Protection Agency (1972) EPA Compdium of Registered Pesticides, Vol. III, Insecticides, Acaricides, VDlluscicides and Antifouling COIlunds, Washington IX, US Governnt Printing Office, p. III-C-7

US Tariff Commssion (1961) S~1thetic Organic Chercals, US Production and Sales, 1960, TC Pulication 34, Washington De, US Governnt Printing Office, p. 161

Vasilos, A.F., Drtrienko, V.D. & Shroit, I.G. (1972) Colchicine- like action of sevine on hum emryonic fibroblasts in vi tro . Byll. eksp. biol. Med.,-- 73, 91 -93 Weil, C.S., Wooside, M.D., Carpnter, c.P. & Smjth, H.F., Jr (1972) Current status of tests of carbaryl for reproductive and teratogenic effect. Toxicol. appl. Pharcol., 21, 390-404

52 Weil, C.S., Wooside, M.D., Bernard, J.B., Condra, N.L, King, ,T.M. & Carpnter, C.P. (1973) Comparative effect of carbarl on rat reproduction and guinea pig teratolog when fed either in the diet or by stomach intubtion. ToxicoL. appL. PharcoL., 26, 621-638

Weyer, L.G. (1974) Gas-liquid chromatographic ræthcx for the analysis of carbar 1 insecticide formulations. J. Ass. of f. anal yt . Chem., 57, 778-780

Whitehurst, W. E., Bishop, E. T., Critchfield, F. E., Gyisco, G.G., Huddleston, E.W., Arnold, H. & Lisk, D.J. (1963) The rætablism of sevin in dairy cows. J. agric. Fd Cher., 11, 167-169

WHO (1974) 1973 Evaluations of sorn pesticide residues in foo. Wld Hlth Org. Pest. Res. Ser., No. 3, pp. 141-176

Wills, J.H., Jamson, E. & Coulstan, F. (1968) Effects of oral doses of carbal on ma. Clin. Toxicol., l, 265-271 Winell, M.A. (1975) An international comparison of hygienic standards for chercals in the work environmnt. Amio, 4, 34-36

Wuu, K.D. & Grant, W.F. (1966) Morphological and somatic chromosornl abrrations induced by pesticides in barley (Hmy:eul'ì I)UlraN!). Canad. J. Genet. Cytol., ~, 481-501

53 CHROPROPHA

1. Chercal and Physical Data

1.1 Synonyr and trade nars

Chem. Abstr. Reg. SeriaI No.: 101-21-3 Cher. Abstr. Nar: (3-Chloropheny 1) carbac acid, 1 -rrthy lethy 1 ester

Chlor-IPC; meta-chlorocarbanilic acid, isopropyl ester; chloro-ICP; chloro IPC; (3-chloropheny 1) carbac acid, isopropy 1 ester; N- (3- chloropheny 1) carbac acid, isopropy 1 ester; N- 3-chloropheny liso- propylcarbamte; CICP; CI-IPC; CIPC; isopropyl 3-chlorocarbanlate; isopropyl meta-chlorocarbalate; isopropyl 3-chlorophenylcarbate; isopropyl N-3-chlorophenyl carbate; O-isopropyl N- (3-chlorophenyl)- carbate

Chlor IFC; Chlor-IFK; Chlorpropham; Elbanil; Fuloe; Liro CIPC; Metoxon; Nexoval; Prevenol; Prevenol 56; Preventol; Preventol 56; Sprout Nip; Spud-Nie; Taterp ; Triherbicide CIPC; Triherbide- CIPC; y 3 1. 2 Chercal formla and rrlecular ~ight o CH3 IL 1 ~HN-C-O-C-H bH3 lQCI C10H12C1ID2 !-l. wt: 213. 7 1. 3 Chercal an physical properties of the substace

From Stecher (1968), unless otherwise spified

(a) Description: Solid

(b) Boiling-point: l490C at 2 TI; 2470 C (decosi tion) at 760 TI (Gad & Fergn, 1964) 0 (c) Mel ting-point: 40.7-4l.1C

55 20 (d) Refractive index: i- = 1. 5395 (super-cooled) (Gard & Ferguon, 1964)

(e) Solubilìty: Slightly soluble in water (Gard & Ferguson, 1964); soluble in rrst oils and organic sol vents

(f) Volatility: Vapour pressure is 10-5-10-6 nm at 250C (exrapolated) (Gard & Ferguson, 1964).

1.4 Technica1 products and imurities

The corrrciai proouct is a liquid (Stecher, 1968). Chloropropham is available in the US as an emulsifiable concentrate containing abut 40% of the pure chercal and as granular fonnlations on an attapulgite clay base containing 10 or 20% by weight of the chemcal (Wee Science Soiety of Arrica, 1974). ln Japan, chloroprophar is available as an emsifiable concentrate containing 45.8% chloroprophar and as a ~ttale r:der containing 7.8% of the chercal (Japaese Ministry of Agriculture and Forestr, 1975).

2. Proouction, Use, Occurence and Analysis

For imrtant background informtion on ths section, see preamle, p. 15. 2 . 1 Proouction and use

Chloroprophar ca te prepared ei ther by the reaction of 3-chloropheny 1 isocyanate wi th isopropy 1 a1cohol or by the reaction of 3-chloroailine with isopropyl ch10roformte (Weed Science Soiety of Amrica, 1974).

It has been proouced comrcially in the US since 1951 (US Tariff Commssion, 1952), but only one us coany mw does so. 'Tie aiunt produced is estimted to have reached abut 300 thousand kg ln 1964 and to have decreased to a leve1 of approximtely 225 thousand kg in 1971.

There are reported to te bM prooucers of chloroprophar in the UK and one in The Nether1ands (Berg, 1975). Anual prcxuction of chloroprophar in Euope is estimted to te less than 1 million kg.

56 It has been produced in Japan since 1962 by one compy, which produced 62 thousand kg in 1974. Imrts in that year were 73 thousand kg (Japaese Ministr of Agriculture and Forestr, 1975).

The onl y known use of chloroprophar is as a highl y selective pre- eirgence and early post-errgence herbicide. It is registered for use in the US on abut 20 crops, including forage, vegetale, fruit and field crops. Residue tolerances in the us have been established in the range of 0.1-0.3 rn!kg for all crops except forage, for which tolerances are from 20-50 rn!kg (US Environrntal Protection Agency, 1974). The quantity of chloropropham used on US agricultural crops in 1971 is estimted to have ben approxitely 200 thousan kg. Ony 9 thousand kg, applied to 5 thousand acres of cropland, were used in the state of California in 1974 (Californa Depatmnt of Foo & Agriculture, 1975).

ln Japan, the following crops are treated wi th this chercal for weed

control (listed in order of quantities of chloropropham used): vege tab les (espeially onions and potatoes), wheat, frut, flCMers and vegetales, turf, miscellaneous herbs and strawbrries (J apanese Miistry of Agri- cul ture and Forestry, 1975). 2 . 2 Occurrence

Chloroprophar does not occu as a natural product. Residual anunts rny occur on or in treated crops after harvsting.

2. 3 Anal ysis

There are several reviews which include nethods of analysis for chloroprophar (Fishbin, 1975; Fishbin & Zielinski, 1967; Gad & Ferguon, 1964; Sherm, 1973; Zweig & Sherr, 1972).

Gas chromatogaphy wi th electron capture detection of the brominated aniline, produced by a one-step hydrolysis and brornation, was used to deterrne chloroprophar extracted from frut and vegetables. The rnthod is sensitive to abut 0.02 rr!kg (Gutenr & Lisk, 1964). Gas chromatography with electrolytic conductivity detection of chloroprophar after alkylation has ben used to deterre chloroprophar extracted fror crops at a lir t of detection of abut O. 005 rr!kg (Laence & Laver, 1975). A ræthod for

57 systemtic identification and deterrnation of a numr of pesticides, including chloroprophar, using a corrination of colur, thin-layer and gas chromatography, has been describd; 200 ng of chloropropham could readily be detected (Suzuki et al., 1974). Bath thn-layer chromatography and high- spe liqud chrOItography have been used to sepaate and detect fluorescent derivatives of the amne produced by alkaline hydrolysis of a numr of carbate and urea herbicides. The thn- layer chromatographic irthod was applicable to the qutitative il1alysis of residues in selected crops at a detection lirt of 0.05 mg/kg (Lawrence & Laver, 1974); 1-10 ng could be detected by high-speed liquid chromatography (Frei & Lawrence, 1973).

A colorimtric rnthod which neasures the 3-chloroailine forrd on alkaline hydrolysis of chloropropham has been used to deterrne residues ln alfalfa. The rnthod includes a clean-up technique which elirates inter- fering plant materials and has a lirt of detection of 0.02 mg/kg (Ercegovich & Witkonton, 1972). Basically the sa colorimtric teclmique, with a different clean-up procedure, has been adapted to an automated system for the analysis of vegetables (Friestad, 1974) and soils (Burge & Gross, 1972), and has a detection lirt of alut 0.01 mg/kg.

3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma 3.1 Carcinogenicity and related studies in anls

(a) Oral admistration

!-use: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F nuce and 1 18 male and 18 femle (C57BL/6xA)F mice received corcial chloro- 1 prophar (98.5% pure) according ta the follcwing schedule: 464 rrg/kg .b in gelatine at 7 days of age by stomach tub and the sar arunt (not adjusted for increasing boy weight) dail y up to 4 'Meks of age; subseqent 1 y, the mice were gi ven 1112 mg chloroprophar per kg of diet. 'le dose was the maum tolerated dose for infant and young rnce but not necessarily so for adults. The exprimnt was terrnated when the anirls were alut 78 wees of age, at which tim 14, 18, 15 and 16 mice in the four groups, respecti vel y, were still alive. Tuur incidences v.re corned with those observed arng

58 79-90 necropsied mice of each sex and strain, which ei thr had been untreated or had recei ved gelatine onl y: the incidences were not significantl y greater (P).0.05) for any tUIur typ in any sex-strain subroup or in the corrined sexes of either strain (Innes et al., 1969; NTIS, 1968).

A group of 25 male and 25 ferle 7-wee old Swss rnce was given 1000 mg chloropropham (rn.p. 40-4loC; containing 30-40 rrg-lkg chloroaniline) per kg of diet for up to 116 weeks, when the suivors ~re killed. Th average lifespa were 78 wes in treated rrles and 84 wes in treated ferles, corned with 75 wees in 25 male and 25 ferle controls fed the stadard diet; 36/47 treated mice had tuiurs, corned with 33/49 controls. Lung adenoms were observed in 15/47 treated mice, coared with 10/49 in controls (van Esch & Kroes, 1972).

Rat: ln a 2-year study, 4 groups of 25 male and 25 ferle young albino rats were given 0, 200, 2000 or 20,000 rn chloropropham (purity not spcified) per kg of diet; of the anils alive at 91 ~eks, 4/9 ferle and 2/11 rrle controls had tuiurs in various organ, as did 2/10 and 1/11 ani.ls in the group given 200 mg per kg of diet, 3/16 and 2/5 in the group given 2000 mg pe kg of diet and 1/10 and 3/5 in the group given 20,000 rn per kg of diet (Lason et al., 1960).

Hater: A group of 23 male and 26 ferle haters was given 2000 mg chloropropham (rn.p. 40-4loC; containing 30-40 rn!kg chloroaniline) per kg of diet for 33 ITnths; a control group of 22 males and 27 femles received the basal diet. After 2 years, 1 treated femle, 1 control femle, 13 treated males and 14 control males ~re alive. Bile-duct hyprplasia in the liver was observed in 19 treated ani.ls and in 28 controls. Six tururs in different organ were seen in treated ani.ls and 8 in controls (van Esch & Kroes, 1972).

(b) Subtaeous adistration

!-use: A group of 25 male and 25 ferle 7-~ek old Swss rrce was given 9 s.c. injections of 1000 mg!kg bw chloroprophar (rn.p. 40-4loC; containing 30-40 mg!kg chloroailine) in 0.025 ml ræthylpyrrolidone at irregar intervals over 17 rrnths. A control group of 25 mice was injected with rnthylpyrolidone alone. Th average lifespans were 78 wæs in treated

59 males and 77 weeks in treated fenles, corred with 70 and 77 W2ek in controls; 20/45 treated mice develope tUIurS (9 having lung adenom), coned with 21/49 controls (13 having lung adenorn) (va Esch & Kroes, 1972) .

Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F rnce and 18 rrle and 18 ferle (C57BL/6xA)F mice W2re given single s.c.1 injections of 1 1000 rr!kg l: comærcial chloropropham (98.5% pure) in dithyl sulphoxide on the 28th day of life and were observed until they wee alut 78 W2ekS of age, a t whch tim 18, 18, 17 and 17 mice in the four groups, respeti vel y, were still ali ve . Tuur incidences were corned wi th those in groups of 141, 154, 161 and 157 untreated or vehcle-injected controls tht were necropsied. Incidences were not signficantly increased (P::O.05) for any tumur typ in any sex-strain suroup or in the coined sexes of ei ther strain (NTIS, 1968) (The Workig Group rited that a negative result obtained with a single s.c. injection may not be an adeqte basis for discounting carcinogenici ty ) . (c) Other exprimtal system ln a tv-stage skin carcinogenesis exrimt, groups of 15 nale and 15 ferle Swiss mice received chloroprophar (rn.p. 40-4loC; containing 30-40 mg!kg chloroaline) either as a single dose of 15 rr in 1% tragacanth by storrch tub or the sai dose W2ekl y for 10 W2eks or in the diet at a concentration of 1000 rr!kg of diet for 6 rrnth. Prortion was induce by painting the skin with a 5% solution of croton oil in olive oil twice weel y for 6 ITnths, stating ei ther 3 days after the first admistration of chloropropha by starrch tub or on the sa day on v.ich the diet containig chloroprophar was given. Six rrnths after the sta of the exprimt the nurrs of mice wi th skin papillomas were: 1/22 in controls only painted with croton oil; 6/24 in rnce given chloropropham by stomch tub once and croton oil; 2/26 in mice given chloropropham 10 tims and croton oil; and 7/28 in mice fed chloropropham in the diet for 6 nonths and given croton oil. 'lur-bearing animls were observed for a further 10 ITnth. A total of 40 papilloms appeared during the tw periods (6 ITnths of treatmnt + 10 rrnths of observation); 7 of these W2re still present 6 rnnths after the end of treatmnt. Tv papillorrs in the sa

60 rruse had progessed to carcinors by th end of the exrirnt. Only 1 turur appeared in untreated controls. ln the sa exrimt, 2 groups of 15 male and 15 ferle Swiss rnce were gi ven 15 m: chloropropha in tragacath by storch tub either once or 10 tis over a period of 10 v;s. A thrd group was fed 1000 m: chloropropham per kg of diet for 6 nonths. All rnce were killed 6 m:mth after the begining of the treatrt. NJ skin tururs appeared, and the incidence of lung adenorrs was not increase (van Esch et al., 1958).

ln a further exprimt, a group of 50 ferle and 50 male Swss mice received 10 weekly admnistrations of 15 m: chloropropham in tragacanth by stomach tub follOWd by twce v;ekly skin applications of croton oil for 26 weeks. There were no differences betwen treated and control anims with regard to the numr of papillor-bearing anls, the total numr of papillors or the proportion of regressing papillonis (va Esch et al., 1965, reported in van Esch & Kroes, 1972). 3. 2 Oter relevant biological data

(a) Exrimental system

The acute oral ID of chloroprophar was 10. 39 g/kg lM in albino rats 50 fed diets containing 26% protein (as casein) and 1. 20 g/kg l: in those fed diets containing no protein (Boyd & Carsky, 1969).

After oral or i. p. admistration of (1 4C-isopropy 1) and (1 4C-ring- lablled) chloroprophar to rats, the 4-day urinar excretions were 50 and 85 % of the dose, respecti vel y, for the tv si tes of lablling; in the case of the isopropyl-lablled coIlund, an additional 17-20% of the dose was excreted as co via the lungs (Bobik et aL., 1972). There was no 2 signficat difference in the rate or route of excretion aing rats receiving oral doses ranging fror 4-200 m:/kg l:; the radioactivity was distributed throughout the boy, wi th highest concentrations in the kidneys (Fang et al., 1974). Hydrolysis of the carbate linage occurred in neomycin-treate rats, and in vitro investigations suggested that the li ver is the si te of hydrol ysis; 40 % of an i. v. dose of chloropropha was excreted in the 6-hour bile (Bobik et al., 1972). Wln pregnant rats were given l4C-chloropropham, the radioactivity was readily tranferred

61 to the foetuses, and i ts level did not decline ln foetal tissues as rapidl y as it did in the maternal organs. The pups of lactating rats tht ~re gi ven lablled chloropropham also contained radioactivity (Fang et al., 1974) .

ln rats, the IIst imrtt irtalic transforntion of chloropropham (1) (Scher 1) is hydroxylation in the para-position and conjugation of the resulting 4-hydroxychloropropha (2) with sulphate. Hydroxylation of the isopropy 1 residue accounts for alut one-third of the irtallism of this herbicide. Approxitel y four tis rrre IInohydroxy cornunds, (3) and (6), than dilydroxy counds (8) ~re detected. Ccund (6) undergoes further oxidation to yield the corresponding l-carboxyethyl derivative (7).

Hydrolytic fission of chloropropham yields meta-chloroanline, carbon dioxide and isopropanol, which is further oxidized ta acetone and carlxm dioxide. Hydroxylation of the librated meta-chloroaline also taes place, to give N-acetyl-4-arno-2-chlorophenol (4) plus N-acetyl-2-aro- 4-chlorophenol (5) (Aleksandrova & Klisenko, 1971a,b; Böhm & Gruaw, 1969; Fang et al., 1974; Gruow et al., 1970; Kosyan, 1972).

Chloropropham inbi ts spindle fibre fo:rtion and induces chrc:aæ abrrations in plants (Nasta & Günther, 1973a; Stroev, 1970) and chlorophyll mutations in baley (Nasta & Günther, 1973b). Petite mutations were induce in Saccharomyces cerevisiae (Schubrt, 1969); but no reverse mutations were detected in Bacillus subtilis (De Giovani-Donnelly et aL., 1968) or in Salmonella typhimurium (Anersen et al., 1972). Metalic activation system were not used in the tests in yeasts and bacteria. (b) Ma

No data were available to the Working Group. 3. 3 Case reports and epiderological studies

No data were available to the Working Group.

62 .. 9 .. e Ui: - gi: - i: o N i)9 i: e ~-\~ i: .. U Ui: i:-4, - i: ..ON U ._~ (,UNi: i: e _'r 0 ~-\o~ 1 1 t~t _ 1 1

i f i~~ i-§ ~-\ 0 5 § UNo U_ 8 t /~ "~ f / ~n~ U-~Ni: i: (§_ i le ~~ l~ ~

,.i: J¿ 1 Ui:Ô _U ~-\ El .. !

63 4. Comænts on Data Reported and Evaluation 4. 1 Animl data

Chloroprophar prcruced no cacinogenic effects when adrnistered orally to mice, rats and haters or subutaeously to rnce. Doses used in the studies in mice and hi16ters did not necessaril y correspond to the maimum tolerated doses.

ln one exprimt wi th oral admistration in rr~ce, chloroprophar acted as an ini tiator of skin cacinogenesis. Ths was not confinr in a subseqent exrimt. 4. 2 Hum data

No case reports or epiderological studies were available to the WJrking Group.

64 5. References

Aleksandrova, L.G. & Klisenko, M.A. (197la) Metalisr of N-phenylcarbac acid derivatives in wablooed anls. Gig. i Sanit., 36, 108-109

Alekandrova, L.G. & Klisenko, M.A. (197lb) Identification of netalic products of sar derivatives of N-phenylcarbac acid in warblooed animls. ln: Tan, O. M., ed., Proceeings of the 2nd l'ül -Union Conference on the Studies on Residues of Pesticides and Prevention of their Pollution on Hi. and Anl Foo and the Environnt, Tallin, 1970, Tallin, Research Institute Epidemological and Microbiological Hygiene, pp. 127-130 Andersen, K.J., Leighty, E.G. & Takahshi, M.T. (1972) Evluation of herbicides for possible mutagenic properties. J. agric. Fd Chem., 20, 649-656

Berg, G.L., ed. (1975) Far Chercals Handbk 1975, Willoughby, Ohio, Meister

Bobik, A., Holder, G.M. & Ryan, A.J. (1972) Excretory and netalic studies of isoprapyl N- (3-chlorophenyl)carbate in the rat. Fd Cosmt. ToxicoL., 10, 163-170 .Bhm, C. & Gruow, W. (1969) u'r den Stoffwchsel von Cabat-Herbiciden in der Ratte. 1. Stoffwchsel des m-coranlin aIs Betadteil von Chlorpropham un Baba. Fd Cosmt. ToxicoL., 7, 125-133

Boyd, E.M. & Carsky, E. (1969) Th acute oral toxicity of the herbicide chlorprophar in alino rats. Arch. environm. Hlth, 19, 621-627

Burge, W.D. & Gross, L.E. (1972) Determnation of IPC, CIPC and propanil,

and sor rntalites of the se herbicides in soil incubtion studies. Soil Sci., 114, 440-443 Californa Departnt of Foo and Agriculture (1975) Pesticide Use Reprt: 1974, Sacramto, p. 32

De Giovani-Donnelly, R., Kolbye, S.M. & Greeves, P.D. (1968) The effects of IPC, CIPC, sevin and zectran on Baci L lus subti lis. Exrientia, 24, 80-81

Ercegovich, C.D. & Witkonton, S. (1972) An imroved rrthod for the analysis of residues of isoprapyl N- (3-chlorophenyl)cabate (chorpropham) in alfalfa. J. agric. Fd Chem., 20, 344-347 van Esch, G.J. & Kroes, R. (1972) Long-terr toxicity studies of chlorpropha and propham in mice and haters. Fd Cosmt. Toxicol., 10, 373-381

65 van Esch, G.J., van Genderen, H. & Vin, H.H. (1958) Th production of skin tunurs in mice by oral treatmt with urethane, isopropyl-N-phenylcarbate or isopropyl-N-chlorophenylcabate in oornination with skin355- painting wi th croton 362 oil and 'Ien 60.- Bri t. J. Cacer, 12, Fang, S.C., Fallin, E., Montganer, M.L. & Free, V.H. (1974) Metalic 4 studies of 1 C-labeled propha and chlorpropha in th femle rat. Pest. Biochem. Physiol., !, 1-11

Fishbin, L. (1975) Chomatogaphy of Environmtal Hazards, VoL. 3, Pesticides, Amterda, Elsevier, pp. 624-626, 688-689 Fishbin, L. & Zielinski, W.L., Jr (1967) Chrorrtography of cabates. Chomat. Rev., ~, 37-101

Frei, R. W. & Lawrence, J.F. (1973) Fluorigenic lablling ln high-speed liquid chrcmtoraphy. J. Chcmt., 83, 321 - 330

Friestad, H.O. (1974) Rapid screeing rrthod, including automated colori- rntr, for lav residue levels of linuron and/or chlorpropha in vegetables. J. Ass. off. analyt. Chem., 57, 221-225

Gad, L.N. & Ferguon, C.E., Jr (1964) CIP. ln: ZW2ig, G., ed., Anal ytical Methods for Pesticides, Plant Gro Relators and Food Addi ti ves, VoL. 4, Herbicides, NEW York, Academc Press, pp. 49-65

Gruow, W., Böhm, c. & Budczies, B. (1970) llr den Stoffwchsel von Carbamt-Herbiciden in der Ratte. II. Stoffwechsel von Chor- propha und Baba. Fd Cosmt. Toxicol., 8, 277-288 Gutenm, W.H. & Lisk, D.J. (1964) Electron affinity residue deterrnation of CIPC, mnuron, diuron, and linuron by direct hydrolysis and bromina- tion. J. agric. Fd Chem., 12, 46-48

Innes, J. R. M., Ulland, B. M., Valerio, M. G., Petrucelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Fal, H.L., Gar, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for tunrigenici ty in mice: a prelirar note. J. nat. Cancer Inst., 42, 1101 - 1114

Japaese Ministr of Agriculture and Forestry (1975) Noyaku Yoran (Agri- cultural Chemcals Anual), 1975, Division of Plant Disease Prevention, Tokyo, Takeo Endo, pp. 38, 88, 95, 313

Kosyan, S.A. (1972) Metablites of sarr phenylcabartes in anirls. In: Prodings of the Confereæe on Toxicology an Hygieæ of Mineral Oil Distillation Procts, Yarslavl, 1971, VoL. 2, Yarslavl Medcal Intitute, pp. 110-115

66 Lason, P.S., Crawford, E.M., Blackll Smth, R., Jr, Henigar, G.R., Haag, H.B. & Finegan, J .K. (1960) Chonic toxicologic studies on isopropyl N- (3-chlorophenyl) cabate (CIPC). Toxicol. appl. Phacol., 2, 659-673 Lawrence, J. F. & Laver, G. W. (1974) An ysis of cabate and urea herbicides in foos, using fluorogenic labling. J. Ass. off. anal yt. Cher., 57, 1022-1025

Lawrence, J.F. & Laver, G.W. (1975) Anlysis of sorr carbate and urea herbicides in foos by gas-liqud chrOItogaphy after alklation. J. agric. Fd Cher., 23, 1106-1109

Nasta, A. & Gtither, E. (1973a) MitoseanOIlien bei AUium cepa und Hordeum vulgare nach Einwirkung eines Cabatherbizids. BioL. Zbl., 92, 27-36

Nasta, A. & Gfther, E. (1973b) Häufigkeit von chlorophylldefekte Pflanzen nach Beandlung mit einer Cabatherbizid und dat korinierten Huta- genen bei Hordeum vulaare.~ Biol. Zbl.,- 92, 173-178 NTIS (National Techical Informtion Serice) (1968) Evluation of Cacino- genic, Teratogenic and Mutagenic Activities of Selected Pesticides and Industrial Chemcals, Vol. l, Carcinogenic Study, Washington IX, US Departmnt of Comrce

Schubrt, A. (1969) Untersuchungen ßbr die Induktion abngsdefekter Hefemtaten durch chersche Pflanzenschutzr ttel . II. Z. a1lg. Miobiol., 9, 483-485

Sherr, J. (1973) Chomatographic analysis of pesticide residues. CR Crit. Rev. analyt. Cher., l, 299-354 Stecher, P .G., ed. (1968) The Merck Index, 8th ed., Raway, ID, ~lfck & Co., p. 261

Still, G.G. & Masager, E.R. (1973) ~~talisr of isopropy 1- 3-chloroc- banlate by cucumr plants. J. agric. Fd Ch., 21, 787-791 Stroev, V.S. (1970) The cyogenetic activity of the herbicides atrazine, chloro-IPC and paaqut. Geetika,~, 31-37

Suzuki, K., Nagayoshi, H. & Kahiwa, T. (1974) Th systertic sepaation and identification of pesticides in the second and thrd division. Agric. Biol. Cher., 38, 1433-1442 US Envirorintal Protection Agency (1974) EPA Cæidium of Reistered Pesticides, Washington OC, US C.,vernnt Printing Office, po. 1-1 -6. 1- 1- 1-6 . 5 US Tariff Commssion (1952) Sythetic Organic Chcals, US Prouction and Sales, 1951, Second Series, Report No. 175, Washington OC, US Govenit Printing Office, p. 135

67 vJee Science Society of AIrica (1974) Herbicide Hadbk, 3rd ed., Charaign, Illinois, pp. 101-106

Zweig, G. & Sherm, J. (1972) CIPC. ln: Zweig, G., ed., Anlytical Methods for Pesticides and--t Grow Reators, Vol. 6, Gas Chorntogaphic Anl ysis, New York, Academc Press, pp. 612-615

68 DIATE

1. Checal and Physical Data 1.1 Synonyr and trade nas

Chem. Abstr. Reg. Serial No.: 2303-16-4

Chem. Abstr. Nar: Bis (l-ræthylethyl) carbathioic acid, S- (2,3- dichloro- 2-propeny 1) ester DATe; 2,3-DC; dichloroallyl diisopropylthocarbate; S- (2, 3- dichloroall y 1) diisopropy 1 thiocbate; 2, 3-dichloroall y 1 N ~ N- diisopropyltholcabate; S- (2, 3-dichloroallyl) -N~ N-diisopropyl- thiolcarbate; S- (2, 3-dichloroallyl)diisopropyltholcarbate; 2, 3-dichloro- 2-propene- 1 -thol, diisopropy lcarbate; diisopropy 1 - thocbac acid, S- (2, 3-dichloroallyl) ester

Avadex; CP 15336 1. 2 Chercal formla and irlecular v.ight

H,C_C/"CI 0 ¡CH) CI,C_C/"CI 0 ¡CHiJ / - " Il 1 / - " Il 1 Ci CHz-S-C- N TH H CHz-S-C-N ~H

CHi CH3 2 2 trans isc:r cis isorrr

C10H17CllDS MoL. wt: 270.2 1.3 Chemcal and physical properties of the substace From Stecher (1968) or Wee Science Soiety of Amrica (1974), unless otherwise specified (a) Description: Brow liqud

(b) Boiling-point: l500C at 9 nm

69 25 (d) Desity: d15.6 1.188

(e) Solubility: Slightly soluble in water (40 :m/1) at roo terature; soluble in acetone, bezene, chlorofonn, ether and heptae

(f) Volatility: Vapour pressure is 1.5 x 10-4 mn at 250C. Evaporation rate is 10.63 x 10-9 rrl/an2. hr at 200C (Guekel et al., 1973).

1. 4 Technical products and iruri ties

Diallate is available in the us as an emlsifiable concentrate containg 45% of the active ingredient and as a granular formation contanig 10% of the chemcal (Weed Science Soiety of Arrica, 1974). Cornrcial fonnulations of diallate contain roughly eqal aiunts of the cis and trans isornrs (Rums, 1975).

2. Production, Use, Ocurrence and Analysis

For imfXxtat background informtion on ths section, see preale, p. 15. 2. 1 Production and use Diallate can be prepared by reacting diisopropylare with carbonyl sulphide and dichloropropee (Stecher, 1968).

It has be produced carrcially in the us since 1961 (US Tariff Corrssion, 1962). The one compy which prcxuces it has recently anounced considerable exsion of i ts capaci ty : a new rnufacturing un t is being installed in the US, and an exsting plant in Belgiur is to be enlarged (Anon., 1975). Anual production of diallate in Euope is estimted to be in the range of 1 ta 5 million kg.

The only know use for diallate is in the selective a:mtrol of wild oats and other weeds in sugar bets, flax, baley, corn, forage legs, lentils, pes, potatoes, soyab, root crops, oil crops, fru t trees and orntals (Wèed Science Soiety of Arrica, 1974). Diallate is registered in the US for pre-planting or pre-emgence incorpration in soil for 11 agricultural crops, largely forage or field crops. Less than 100 thousand kg

70 were used on all agricutural crops in the US in 1971. A residue tolerance of 0.05 IT/kg has æen established in the US for these crops (US Environmtal Protection Agency, 1972). Th residue tolerance in Euope is of the order of O. 1 IT/kg. 2. 2 Occurence

Diallate is not knON to occur as a natural prcxuct. It has an average half- life of abut 30 days in sail when applied at recorded rates (1.5- 3.5 pounds/acre) (Wee Science Society of Arrica, 1974). Residual arunts may occur on or in treated crops after haresting.

2.3 Analysis

A th- layer chrortogaphy ræthcx for systemtic separation and detection of sixt y-one pesticides, including diallate, has ben describ; the lirt of detection for diallate was 0.5 l1g or 2.0 l1g, depeding on the system emloyed (Ebing, 1972). Prepaative gas-liquid chomatogaphy was used in one study to sepaate the cis and trans isornrs of diallate for identification by techniques such as nuclear rngnetic resonance and infra-red spetrortr (Rurs, 1975).

3. Biological Data Relevant ta the Evluation of Carcinogenic Risk to Ma

3.1 Carcinogenicity and related studies in animls

(a) Oral admnistration

!-use: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F rnce and 1 18 male and 18 fanle (C57BL/6xA) F mice received corcial diallate 1 (b.p. l45-l500c at 9 rr) according ta the fOllCMing schedule: 215 IT/kg l: in gelatine at 7 days of age by storch tub and the sa arunt (not adjusted for increasing l: weight) daily up ta 4 v.eks of age; subseqently, the mice were given 560 mg diallate per kg of diet. The dose was the rniri. tolerated dose for infant and young rnce but not necessarily so for adults. The exprimt was terrated when the anim:Üs were alut 78 weeks of age, at which tir 15, 16, 16 and 14 mice in th four groups, respectively, were still ali ve. 'lur incidences were cornred wi th those observed arng

71 79-90 necropsied mice of each sex and strain, which either had been untreated or had received gelatine only. The incidence of hepatomas in necropsied mle (C57BL/6xC3H/Anf)F mice was 13/16, comped with 8/79 in controls; that in necropsied male1 (C57BL/6xA)F rnce was 10/18, CDared with 5/90 1 in controls (P':O.OOl). The incidences of hepatomas anng ferles were 3/16 in the first strain, comped with 0/87 in controls, and 1/15 in the second, comped with 1/82 in controls (P?O. 05). ln addition, 4/16 (C57BL/6xC3H/Anf)F male rnce died with lung adenomas, compared with 5/79 1 controls (P?0.05) (Innes et al., 1969; NTIS, 1968). Rat: Results of a 2-year feeing study with diallate ln Chles River CD rats were reported briefly (Ulland et al., 1973) (Th inadeqate reporting does not alla, an evaluation of this exrirt).

(b) Subcutaeous admistration

Mouse: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F rnce and 1 18 male and 18 femle (C57BL/6xA)F rnce were given single s.c. injections 1 of 1000 rn/kg bw comærcial diallate (b.p. l46-l500C at 9 nm) in corn oil on the 28th day of life and were observed until they were alut 78 weeks of age, at which tire 17, 18, 18 and 15 rnce in the four groups, respecti vel y, were still ali ve. Tuur incidences were cc:ed wi th those in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. Systemc reticulumcell sarcomas develope in 4/18 necropsied ma1e (C57BL/6xC3H/Anf)F mice, corned with 8/141 control males of that 1 strain (P.:0.05). Such tururs were not observed in treated males of the second strain (NTIS, 1968).

3.2 other relevant biological data

(a) Exrimtal system

Oral LD values for diallate ln rats range froID 393-1000 rn/kg bw; 50 the derml LD in rabbits is 2000-2500 rn/kg bw (Ben-Dyke et al., 1970). 50 ln mice, rats and cats, injection of diallate caused central nervous system excitation, which progressed within a few minutes to depression and clonic- tonic convulsions (Pestova, 1966).

72 Repeated application of diallate to the eyes and skin of guea-pigs and rabbits caused local irritation, which was followed by loss of weight, neutrophile leucocosis, eosinopenia and eryopeia; oral and subtaeous admnistration produced sirlar effects (Doloshitsky, 1969; Gzhegotsky & Doloshitsky, 1971).

Tests for reverse mutations in Salmone lla typhimurium strains were negative for base substitution and fram-shift mutations (And.ersen et al., 1972) ; rntablic activation system were not used in these tests.

(b) M3

No data were available to the Working Group. 3 . 3 Case reports and epidemological studies

No data were available to the Working Group.

4. Corrents on Data Reported and Evaluation 1 4 . 1 Animl data

Diallate is carcinogenic in rrce after its oral admistration: it produced an increased incidence of liver-cell tumurs in males of tw strains and a slight increase in the nurr of liver-cell tumurs in femles of one strain. A single subutaeous injection in rnce produce a slight increase in the incidence of systerc reticul~cell sarcomas in males of one strain. 4.2 Hum data

No case reports or epidemological studies were available to the Working Group.

1 See also the section, 'Animl data in relation to the evaluation of risk to ma' in the introduction ta this volur, p. 13.

73 5. References

Andersen, K.J., Leighty, E.G. & Takahashi, M. T. (1972) Evluation of herbicides for possible mutagenic properties. J. agric. Fd Cher., 20, 649-656 Anon. (1975) It s news to IT. Fertilizer Solutions, Janua-Februar, p. 107

Ben-Dyke, R., Sanderson, D.M. & Noes, D.N. (1970) Acute toxicity data for pesticides. Wld Rev. Pest. Contr., 9, 119-127

Doloshitsky, S.L. (1969) Hygienic standardization of herbicide avadex containing chlorine in water. Gig. i Sanit., 34, 21-28

Ebing, W. (1972) Routinerthode zur dtischichtchromtographischen ldeti- fizierug der Pestizidrckstfue aus der Klassen der Triazine, Carbate, Harnstoffe und Uracile. J. O1ort., 65, 533-545

Güeckel, W., Synatschke, G. & Rittig, R. (1973) A rrthod for deterrning the volatili ty of active ingredients used in plant protection. Pest. Sci., i, 137-147

Gzhegotsky, M.1. & Doloshitsky, S.L. (1971) Skin resorption effect of herbicides. Vrach. Delo, 11, 133-134

Innes, J.R.M., Ullan, B.M., Valerio, M.G., Petrucelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and indus trial chemcals for turrigenici ty in mice: a prelirnar note. J. nat. Cancer Inst., 42, 1101-1114

NTIS (National Techncal Informtion Seice) (1968) Evluation of Cacino- genic, Teratogenic and Mutagenic Acti vi ties of Selected Pesticides and Industrial Chemcals, Vol. l, Carcinogenic Study, Washington IX, US Deparnt of Coirce

Pestova, A.G. (1966) Toxicity of diptal and avadex. Gig. ToksikoL. Pest. Klin. Oltravleny, 4, 166-169

Ris, F .H.A. (1975) Separation and strctural assigrt of the cis and trans isaærs of S- (2, 3-dichloroallyl) diisopropylthiocarbate (diallate). Weed Sci., 23, 7-10

Stecher, P.G., ed. (1968) The Merck Index, 8th ed., Raway, ID, ~rck & Co., p. 337

Ulland, B., Weisburger, E.K. & Weisburger, J.H. (1973) Chronic toxicity and carcinogenici ty of industrial chemcals and pesticides. Toxicol. appl. Pharcol., 25, 446

74 US Envirortal Protection Agency (1972) EPA ~dium of Reistered Pesticides, Washigt De, US Governt Printing Office, pp. I-D-18.l - I-D-18.2 US Tariff Ccmssion (1962) Synthetic Organic Chemcals, us Proouction and Sales, 1961, TC Pulication 72, washington De, US Govenut Printing Office, p. 167

Wee Science Society of Arrica (1974) Herbicide Handb, 3rd ed., Chargn, Illinois, p. 136

75 DIMYL CHRIE

1. Chemcal and Physical Data

1.1 Synonyr and trade nclS

Chem. Abstr. Reg. Serial No.: 79-44-7

Chem. Abstr. Ncl: Dimthy lcarbac chloride

(Dimthy larno) carbony 1 chloride; dimthy lcarbac acid chloride; dimthy lcabamdoy 1 chloride; dimthy 1 cabay 1 chloride; N -' N- dimthy lcarbarY 1 chloride; direthy lcarba 1 chloridA; N -' N-dimthy 1- carba 1 chloride

1.2 Chercal formla and molecular weight CH3~ " 0 /' N-C-CI CH3

C3H6C1ID 1'101. wt: 107.6 1. 3 Chemcal and physical properties of the substance

(a) Description: Liqud

(b) Boiling-point: 47-490C at 12 mm (Hasserodt, 1968); 640C at 20 mm (Birkofer & Krebs, 1968)

(c) Melting-point: -330C (von Hey et al., 1974) 20 (d) Desity: d4 1.1678 (Prager & Jacobson, 1922) 20 (e) Refractive index: ~ 1. 4529 (Hasserodt, 1968) (f) Stability: Rapidly hydrolyses in water ta dithylarne, carbon dioxide and hydrogen chloride; its half-life at OOC is alut 6 minutes (Van Duuren et al., 1972) 1. 4 Technical products and imuri ties

No data were available to the Working Group.

77 2. Production, Use, Occuence and Anal ysis For imrtant background inforntion on this section, see preaile, p. 15. 2 . 1 Production and use

Michler & Escherich (1879) first reported preparation of dimthylcarbayl chloride by the reaction of dithylarne with phosgene, and this process is believed to be used curentl y for i ts comærcial production. Dimthylcabaryl chloride was produced in the us between 1958 (US Tariff Commssion, 1959) and 1971 (US Tariff Commssion, 1973). Although there were five US maufacturers producing this chemcal in the pat, there is now only one, who maes less than 450 kg per year.

The maufacture of dimthy lcarbay 1 chloride was be in the Federal Republic of Germy in 1961, and approxitely 120 thousand kg are produced each year (von Hey et aL., 1974). It is also maufactured and used in the UK (Anon., 1975a).

The onl y known use of dimthy lcarbay 1 chloride is as a chemcal interiate in the production of drgs and pesticides. Dimthylcarbaryl chloride-derived paasympathomitic (cholinergic) agents being used for treatmnt of rnasthenia gravis in the US are: pyridostigrne brornde (rcstinon brorde; 3-hydroxy- i -methylpyridinium brorde dimthylcarbarte) ; neostigrne bromide (3-dimthylcarbaxyhenyl trimthylanm:mium bromide) ; and neostigre rcthylsulphate (3-dithylcarbaxyhenyl trimthylarrm::miur rnthyl sulphate). The dimthylcarbayl chloride-derived pesticides approved by the US Environrntal Protection Agency for use in the us are: the herbicide, tandex (meta- (3, 3-dimthylureido)phenyl-tert-butylcarbate) (Johnson, 1972); the insecticide, dimtilan (2-dimthy lcarbay 1 - 3-rnthy l-5-pyrazol y 1 dimthylcarbate) (US Environrntal Protection Agency, 1972); and the aphicide, pirimr (pirircarb; 5, 6-dimthyl -2-dimthylarno-4-pyrirdinyl dimthyl carbamte) (Aron., 1975b). Several dimthylcarbayl chloride-derived pesticides are not approved by the US Eniro:nntal Protetion Age:r for use in the us but are believed

78 to be used elsewhere; these are: isolan (1-isopropyl-3-irthyl-5-pyrazolyl dimthylcarbate); pyrolan (l-phenyl -3-rnthyl -5-pyrazolyldimthylcarbate) ; and dimta (5,5-dimthyldihydroresorcinol dithylcarbate) .

2 . 2 Occurrence Dimthylcarbayl chloride is not know to occur as a natural product. ln one rnufacturing plant in the Federal Republic of Gey, the production of dimthylcabayl chloride is carried out in a closed system; during evacuation and cleaing, \orkers wear respirators and gloves. Concentrations of up ta 1.5 ppn (7 mg/m 3) have ben rei;rtd in the air (von Hey et aL., 1974). It is possible that levels of exsure rnght be cons iderab 1 y higher in facili ties in which the chemcal is used for further synthesis. ln any such situation where closed system are not used a potential exsure ff::iy exist for bath \orkers and the coi ty . 2. 3 Anal ysis

ln one rnthod dirthylcarbayl chloride was reacted with 4- (para- nitrobenzyl)pyridine in a triethylarne-rnthylethyl ketone solvent for 8 hours at 500C. The resulting product was analysed spectrophotoirtrically (Agree & Meeker, 1966). A rrre sensitive rrthod to detect levels as low as 17 ppb in the air, using acetone as the sol vent, has been reported (Rusch et al., 1976).

Gas chromatogaphy has been used to rrasure atispheric levels in working environrnts. Levels as 1O\ as O. 06 ppm (O. 3 m;:/m 3) were reported, but no indication was given as to the lowr lirt of sensitivity of the irthod (von Hey et aL., 1974).

3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma

3.1 Carcinogenicity and related studies in animls

(a) Skin application

Mouse: Of 50 femle ICR/Ha Swiss mice given 2 mg dithylcarbamyl chloride (b.p. 840C at 50 mn) in 0.1 ml acetone on the interscapular region thice weekly during 492 days, 40 develope skin papillomas (persisting at

79 least 30 days); of these, 30 progessed to skin cacinomas. The rran surival tir was 386 days, comred with 543 days in 50 controls receiving acetone onl y. No tururs at other si tes are ræntioned in ths paper (Van Duuren et aL., 1974); ho,ever, in a prelirnar report of the sar study, 2/26 treated and 0/9 control animls dying before 385 days had papillar tururs of the lungs (Van Duuren et al., 1972).

Of 30 femle ICR/Ha Swiss rnce given a single application of 2 mg dirthylcarbayl chloride in 0.1 ml acetone followed 2 weeks later by 3 applications per week of 2. 5 lig phorbol rnristy 1 acetate (PMl) in 0.1 ml acetone for the duration of the exrirt (rrre than 385 days), 6 developed skin papillors, the first appearing 79 days after the start of PM treatrnt. Papillors occured in 3/30 controls recei ving I= only, the first tUIur appearing at 224 days, and in 0/30 rnce given a single application of dirthylcarbayl chloride (Van Duuen et aL., 1974).

(b) Subutaneous admistration

Mouse: Of 50 femle ICR/Ha Swiss rnce given vvekly s.e. injections of 5 mg dimthylcarbaiyl chloride (b.p. 840C at 50 rr) in 0.05 ml tricaprylin for 26 weeks, 36 developed local sacorns, and 3 had local squaius-cell carcinorns. The rndian surival tir was 280 days, corred with 493 days in controls recei ving sol vent alone. Of 50 controls, 1 developed a sarcoma (P~O. 01), and none had carcinomas. No tUIurS at other sites are rrntioned in this report, even though anirls vvre autopsied cornletely except for the cranial region (Van Duuren et al., 1974); hov.ver, in a prelirnar report of the sar study, of 47/50 treated and 4/30 control anirls dying before 385 days, 4 of the treated group and 0 of the control group had papillary tururs of the lungs (Van Duuren et aZ., 1972). (c) Intraperitoneal admistration

Mouse: Of 30 femle ICR/Ha Swss rnce given weekly i.p. injections of 1 mg dimthylcarbayl chloride in 0.05 ml tricaprylin for up to 450 days (end of the exprimnt), 14 develope papillary tururs of the lungs, cornared with 10/30 mice given tricaprylin alone and with 29/100 untreated rnce. Eight trea ted mice and 1 control gi ven the sol vent alone developed local sarcorns, and 1 treated rruse develope a sqaius-cell carcinoma of the skin (Van Duuren et al., 1974).

80 3.2 Other relevant biological data

(a) Exrimntal system

ln mice, the i.p. LD is approxitely 350 m::/kg bw¡ in rats, the 50 oral LD for dLnethylcarbayl chloride in oil is approxLnately 1170 mg/kg 50 bw (von Hey et al., 1974).

Rats to1erated an 8-minute exsure to an atmsphere saturated at 200C with dimthy1carbamyl chloride and surived 14 days post-expsure¡ but when anirls were expsed for 1 or 2 hours, 5/6 or 6/6 died, respectively. Dimthylcarbayl chloride dages rncous iæranes of the nase, throat and 1ungs and causes difficulty in breathing, sometirs only after several days. Skin application of undiluted dimthylcarbayl chloride to rats and rabbits produced skin irritation, with subseqent degeneration of the epiderrs and outer dennl strctures; skin--sensitization tests in gunea-pigs were negative. Conjunctivitis and keratitis occued in irritation tests in rabbit's eyes (von Hey et al., 1974). Dimthylcarbayl chloride behaves as a direct-acting acylating carcinogen, which is consistent with the production in vivo of the corresponding carbonium ion (Van Duuren et al., 1972). Dimthy1carbamy1 chloride (5.3 ng) induced reverse mutations in 8almoneUa typhimuriur!1 strains TA1535 and Th100¡ no metablic activation was reqired (McCan et al., 1975). (b) Ma

One case of eye irritation and one of liver disturbaces have been observed in workers expsed to dimthylcarbayl chloride (von Hey et al., 1974) . 3. 3 Case reports and epidemological studies

No cancer death (out of a total of 6 deaths) or X-ray indications of lung cancer were reported in an investigation of 39 dithylcarbayl chloride production workers (3 of whom VIre ferles), 26 processing vvrkers and 42 ex-workers, aged 17-65 and exsed for periods ranging froID 6 months to 12 years (von Hey et al., 1974).

81 4. Comæts on Data Reported and Evaluation 1 4. 1 Animl data Dimthylcarbayl chloride is cacinogenic in rrce by skin application or by subutaeous or intraperi toneal inj ection: i t produced local tUIurs by each of the three routes of admnistration. 4 . 2 Hur data The available epiderological study 1S inadeqate to assess the carcinogenici ty of this cOl1und in nan.

lSee also the section, 'Animl data in relation to the evaluation of risk to rr' in the introduction ta ths volur, p. 13.

82 5. References

Agree, A.M. & Meker, R.L. (1966) Quatitative deterrnation of micro and sem-micro concentrations of acylating agents by 4- (p-nitrobenzyl) pyridine reagent. Talanta, 13, 1151-1160

Anon. (197 Sa) ln brief. Checal Age, Janua 24, p. 19

Anon. (1975b) 1975 Pesticide roundup. Far Chemcals, 138, 50 Birkofer, L. & Krebs, K. (1968) N, N-Disubstituierte Cabayl - und Thiocbay lchloride tfr Sil y 1 -Deri vate. Tetrahedon Lett., 7, 885-888 Hasserodt, U. (1968) Die Reaktion von Schwefeldichlorid, Dischwefeldichlorid und Sulfurlchlorid mit (Thio)Arden zu (Tho)Carbamdsãurechloriden und Senfölen. Chem. Ber., 101, 113-120 von Hey, W., Thiess, A.M. & Zeller, H. (1974) Zur Frage etwaiger Gesund- hei tsschãdigugen bei der Herstellung und Verarbei tung von Dirthy 1 - carbansãurechlorid. ZbL. Arbeitsr., 24, 71-77

Johnson, O. (1972) Pesticides 1972. II. Chemcal Week, July 26 McC, J., Spingarn, N.E., Kobori, J. & AIs, B.N. (1975) Detection of carcinogens as mutagens: bacterial tester strains wi th R factor plasrds. Proc. nat. Acad. Sci. (Wash.), 72, 979-983

Michler, W. & Escherich, C. (1879) Concernng rnltiple-substituted ureas. Cher. Ber., 12, 1162-1164

Prager, B. & Jacobson, P., eds (1922) Beilsteins Handbuch der organschen Cheme, 4th ed., VoL. 4, Syst. l'. 335, Berlin, Sprin:er-Verlag, p. 73 Ruch, G.M., La Mendola, S.L., Katz, G.V. & Laskin, S. (1976) Determnation of low levels of dimthylcarbayl chloride in air. Analyt. Chem. (in press) us Environrntal Protection Agency (1972) EPA Compndium of Registered Pesticides, VoL. III, Insecticides, Acaricides, tblluscicides, and Antifouling Compunds, Washington IX, US Governnt Printing Office, p. III -H-5

US Tariff Corrssion (1959) S~thetic Organic Chercals, us Production and Sales, 1958, Report No. ¿ , Second Series, Washingn IX, US Goverrnt Printing Office, p. 145

US Tariff Conrssion (1973) Synthetic Organc Chemcals, US Production and Sales, 1971, TC Pulication 614, Washington IX, US Governt Printing Office, p. 218

83 Van Duuren, B.L., Goldscldt, B.M., Katz, C. & Seidm, 1. (1972) Dirthy1cabe1 ch10ride, a multipotential carcinogen. J. nat. Cacer Inst., 48, 1539-1541 Van Duuren, B.L., Go1dschdt, B.M., Katz, C., Seidm, 1. & Paul, J .S. (1974) Cacinogenic activity of alk1ating agents. J. nat. Cacer Inst., 53, 695-700

84 DI SU lRA*

1. Chemcal and Physical Data 1. 1 Synonyr and trade nars

Chem. Abstr. Reg. Serial No.: 97-77-8

Cher. Abstr. Nare: Tetraethy 1 thioperoxydicarbonic diamde Bis ( (diethy lamno) thioxornthy 1 J disulphide; bis (diethy 1 thocarbay 1) disulphide; bis (N ~ N-diethy 1 thiocbay 1) disulphide; disulphurar; 1,1'-dithiobis(N~N-diethylthioformde); ethyl thrar; ethyl thiurad; TATD; TET; tetraethylthiram disulphide; tetraethylthiuram; tetraethylthuram disulphide; N~ N~ N' ~ N' -tetraethylthurar disulphide; tetraethy 1 thiuran disulphide; Ti Abstensil; Abstiny 1; Alcophobin; Antabus; Antabuse; Antadix; Antethyl; Antalcol; Antietaol; Antietil; Antikol; Aversan; Contralin; Cronetal; Ekagorn TES; Espral; Etaus; Ethy 1 tuads; Ethy 1 Tuex; Exorran; Noxal; RefusaI; Stopety 1 ; Tetradine; Tetraetil; Thiurar E; Thiuranide 1. 2 Chemcal formla and rnlecular weight

CH3-CHi S S CHi-CH3 ~N-C-S-S-C-N Il Il / CH3-CHi/ CHi-CH3~

C10H20N2S 4 ~bi. wt: 296.5 1. 3 Chemcal and physical properties of the pure substance

(a) Description: Yellowish-white crystals (Stecher, 1968) o (b) M.l ting-point: 70 C (Stecher, 1968); 7L-720C (Weast, 1975)

*Much of the inforntion on the carcinogenicity of ths substace refers to the ruber-processing grade chemcal.

85 (c) Spectroscopy data: For infra-red and nuclear rrgnetic resonance spetral data, see Grasselli (1973).

(d) Solubility: At 250C, soluble in water (0.02 g/lOO ml), ethanol (3.82 g/lOO ml), ether (7.14 g/lOO ml); also soluble in acetone, benzene, chlorofom and carbon disulphide (Stecher, 1968) 1. 4 Techncal products and imuri ties

Disulfirar is available in the US for ruber processing with the fOllOling typical specifications: physical state, cus; colour, buff to light grey; density, 1.27 :: 0.03; rnlting range, 63-750C; ash, 0.5% IT.; ITisture, 1. 0% ma.; available sulphur, 10.8% (Ann., 1973, 1975). It is also available in a dispersion oontaig 25-30% binder and in a 50 :50 mixture wi th thiram (rnthy 1 tuads) (Ann., 1975). For rrcinal purses, a pharceutical grade of disulfiram is available as talets containing up to 500 IT (Anon., 1976).

2 . Production, Use, Occurrence and Anal ysis

For ÌIrtt background informtion on ths section, see preale, p. 15. 2. 1 Production and use

The first reported prepaation of disulfirar was by the addition of iodine to an ethrolic solution of the diethylarne salt of diethyldithiocarbac acid (Grodzki, 1881). It ca æ prepared by adding sulphuric acid and hydrogen peroxide to an aqueous solution of soium diethyldithocarbate (Shaver, 1968), or by treating sodum diethyldithiocabate with soium hyphlorite (Bailey, 1931).

Commrcial production of disulfiram in the US was first reported in 1940 (US Tariff Commssion, 1941), and thee rnufacturers reported production in 1974 (US International Trade Cæission, 1975). It is also produced in the Benelux countries, France, L tal y and the UK. Wor ld production of disulfirar is estirted to be from 510 to 550 thousand kg per year.

The rrjor use of disulfirar is as an acceleratar in cOIlp:mnd.ing natural, styene-butadiene, isobuty lene- isoprene and Neoprene W rubers. l t is

86 fast-curing, non-discolouring and non-staining and can be used wi th or without sulphur. It can be used as a primry or secondar accelerator with aldehyde ames and guidines and is also used as a cue retarder in chloroprene and Neoprene G rubers (Ann., 1975).

Pharceutical grade disulfirar is used in aversion therapy for chronic alcoholisr (Anon., 1976). Theatrnt consists generally of a single dose of 0.5 g during 1-2 weeks, then 0.25 g/day. It is estimted that less than 5 thousand kg disulfirar are used in hur rricine in the US anuall y.

Although disulfiram may have be used as a pesticide, it has not been approved for tht use in the US by the Environmtal Protection Agency. ln 1975, the Arrican Conference of Govermt Industrial Hygienists set 2 mg/rn3 as a trial theshold lirt value for disulfirar in the workplace air over any eight-hour workshift for a forty-hour v-rk ~ek (ACGIH, 1975). 2 . 2 Occurence Disulfiram ls not knCM to occu as a natural product. 2 . 3 Anal ysis

Methods for the chromatographic analysis of carbates, including disulfiram, have been reviewed (Fishbin & Zielinski, 1967).

When heated with sulphuric acid, disulfirar is qutitatively converted to carbon disulphide, which ca te deterrned as copper diethyldithiocarbarte. Differential cathode ray polarography has ben used to estimte disulfirar in hum bloo; 85 to 105% was recovered from 1 ml of citrated whole hur bloo containing 1. 0 to 30 iig. The carbon disulphide present in the exaled air of patients treated with disulfirar may be deterrned sirlarly (BrCM et aL., 1974). A sïrlar procedure was used to deterrne the presence of disulfiram added to urine; recoveries were 85-95% (Porter & William, 1972). Agas chrOItographic rnthod for the deterrnation of carbon disulphide in the exhaled air of disulfirar-treated patients has teen describd (Wells & Koves, 1974).

87 3. Biological Data Relevant to the Evaluation of Carcinogenic Risk to Mm

3.1 Cacinogenici ty and related studies in animls

(a) Oral admistration

!-use: Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F rmce and 18 male and 18 ferle (C57BL/6xA)F rncereceived corcial disulfirar1 1 (ruber-processing grade; m.p. 63-750C) according to the following schedule: 100 rn/kg hw in gelatine at 7 days of age by stamch tub and the sar arunt (not adjusted for increasing 1:y weight) daily up to 4 weeks of age; subseqently, the mice were given 323 rn per kg of diet. The dose was the maim tolerated dose for infant and young rnce but not necessaril y so for adults. The exprirnt was terrated when the animls were abut 78 weeks of age, at which tiI 15, 18, 7 and 15 mice in the four groups, respectively, were still alive. Tuur incidences v.re caed with those observed arng 79-90 necropsied mice of each strain and sex, which either had ben untreated or had received gelatine only. An excess number of turur-bearing animls was found arng males of bath strains (first strain, 10/17 necropsied versus 22/79 controls (p~O. 02 J; second strain, 13/16 necropsied versus 16/90 controls (p~O. 001 J ) . ln males of the first strain, pulInar adenomas were found in 5/17, cc:ared with 5/79 in controls (P~O. 01), and hepatams in 8/17, corned with 8/79 in controls (P~O. 001) . ln males of the second strain, onl y subtaeous fibrosarcomas were found in excess and were present in 10/16 necropsied rnce (Innes et al., 1969; NTIS, 1968). (The occurence of a substatial numr of suutaneous sarcomas in mice following the oral admstration of a chemcal is extreml y unusual in chercal carcinogenesis exrirts. Ths observtion raises soræ doubts as to the signif icance of the abve finding J .

Rat: A group of 40 l4-~k old SpraguDawley male rats was given an aqueous solution of cOI1rcial disulfirar by sto:mch tub twice weekly for an unspeified numr of weeks; th v.ekly dose was 500 rn/kg bt. Mean suri val tim was 65 v.eks. Tv animls develope a benign inter- sti tial -cell turur of the testis; no other tuiurs v.re observed. A:ng 600 untreated control rats, whse ITan surival ti1 wa 98 wees, 38

88 develope a total of 42 tumurs at different sites (Schhl et al., 1976) (The Working Group noted the inadeqte duration of ths exriint).

(b) Subtaeous admistration

MJuse: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F nuce and 18 male and 18 femle (C57BL/6xA)F mice v;re given single s.c.1 injections 1 of 1000 mg/kg bw corrrcial disulfirar (ruber-processing grade; m.p. 63- 750C) in 0.5% gelatine at 28 days of age and were obsered until they were abut 78 weeks of age, at which tim 15, 17, 18, and 18 rnce in the four groups, respetively, were still alive. Tuur incidences were corned with those in groups of 141, 154, 161 and 157 untreated or vehcle-injected controls tht were necropsied. An increased incidence of reticulurcell sarcos was found in 3/18 femles of the second strain, cornared with 5/157 controls (P~O. 05) (NTIS, 1968).

3.2 Other relevant biological data

(a) Exrimtal system Onl Y miniml signs of toxici ty v;re seen ln nuce adnistered up to 10 gjkg bw disulfirar orally. Oral ID 's in rats, rabbits and dogs ranged 5 u from 2-10 g/kg bw. Major signs of severe toxicity v;re ataa, hyptherra and flaccid paalysis (Child & Cru, 1952). ln rats, concentrations of 100-2500 mg per kg of diet were given for up to 2 years; toxic effects occued only at the highest concentration, at as early as 8 v;eks (Fitzhugh et al., 1952). Oter investigations sho.d that chronic dosing with 1000-2000 rrjkg of diet with disulfirar retards the grCM and reproductive capacity of rats and decreases longevity (Holck et aL., 1970). Doses of 25-500 mg/kg bw disulfiram have anti-thyroid properties (Chistensen & Wase, 1954).

ln rats, the following rntallites of disulfiram were found: diethyl- dithocabate, diethyldithiocarbte S-glucuonide, inorganc sulphate, diethy lamne and cabon disulphide. A smll arunt of the S was bound ta proteins as rnxed disulphides. After i.p. injection of 10 rr, 8% of the -SH groups of plasm proteins and alut 0.1-0.2 % of the -SH groups of the soluble liver pro teins were blocked (Strörr, 1963, 1965). Disulfiram has be shaw to inhibit the activity of aldehyde dehydrogenase, resulting in

89 acetaldehyde accumation (Hald & Jacobsen, 1948), of dopae ß-hydroxylase (Goldstein, 1966), hexokinase (Strömr, 1963), glyceraldehyde 3-phosphate dehydrogense (Nygaard & Sumer, 1952), xathne oxidase (Richert et al., 1950) and D-amno acid oxidase (Neir et al., 1966) and to depress cytochrorr P-450 levels (Zemitis & Greene, 1976). The rnchanisr of disulfir~ethol interaction in vivo is incornletely understoo (van Logten, 1972). Thus, disulfiram (Hald et al., 1949; Lasen, 1948), or one of its rntalites, diethyldithocarbate (Da et al., 1949; Eldjarn, 1950a) or carbon disulphide (Johnston & Prickett, 1952; Prickett & Johnson, 1953), may interfere with norml ethanol rrtallism and sa give rise to toxic arunts of interrdiar products (Hald et aL., 1949; Lasen, 1948). On the other hand, ethanl may interfere with the catallism of disulfirar to rne it rrre toxic (Strömne, 1963). The acute toxici ty of N-ni trosodethy lamne in rats and mice and the N-7-rnthylation of guanine in liver DNA were reduced by sirultaeous admnistration of disulfirar (Schm et al., 1971).

The inhitory effect of disulfiram on cacinogenesis has been demnstrated for benzo (a) pyene-induced forestornch tumurs in mice (Wattenbrg, 1974), for 1,2-dimthylhydrazine-induced large-intestine tumurs in mice (Wattenbrg, 1975), for dimthylbnzanthacene-induce rr tumurs in rats (Wattenbrg, 1974) and for N-nitrosoimethyl- and N-nitrosodiethylamne-induced liver tumurs in rats but not for other tumurs induced by these nitrosames (Scli et al., 1976).

Disulfiram can react with nitrite ta forr N-nitrosodiethylamne

(Lijinsky et al., 1972). (b) Ma The rntalisr of disulfiram in ma is sirlar to that in anls (Asrnssen et al., 1948a,b; Eldjar, 1950b; Hald & Jacobsen, 1948; Hald et al., 1948; Kaslander, 1963; Merlevede & Caier, 1961). Str's observation (Ström:, 1965) tht ethol interferes with the catablisr of disulfirar also applies in ma.

90 Lilly (1975) has examned chromosomes from alcoholics treated with total doses of disulfiram ranging from 0.6-93 g per person. No increase in the nurr of chromosorn abrrations was found. Tests in vi tro on cultured lymhoctes with 10-4-10-8 M disulfirar also revealed no effect on the chrOIsorrs. 3 . 3 Case reports and epidemological studies

No data were available to the Working Group.

4. Corrts on Data Reported and Evluation

4.1 Animl data Disulfiram (of ruber-processing grade) was tested by oral admistration and by single subutaeous injection in tw strains of rnce. When gi ven by the oral route i t increased the incidence of li ver-cell tururs and caused a slight increase ln the nurr of lung tUIurs in rnles of one strain but not in those of the other.

These results are derived from a study in which an Ì1ure rnterial was tested. Studies on phaceutical grade rnterial are nCM underay in a numr of labratories (IA Informtion Buletin l'. 6).

The lirted data availale do rot allow an evaluation of the carcinoenici ty of disulfira ta be ma.

Disulfirar can react with nitrite under mildly acid conditions, sirulating those in the hum starnch, to forr N-nitrosodiethylame, which has ben shaw to be ærcinogenic in te animl species (IA, 1972). 4.2 Hum data

No case reports or epidemological studies were available to the Working Group.

91 5. References

ACGIH (~can Conference of Goverrnt Industrial Hygienists) (1975) TLVs \E Theshold Lir t Values For Checal Substances in Workroom Air Adopted by ACGIH for 1975, Cincinnati, Ohio, p. 38 Anon. (1973) Ethyl Tuads (B , New York, R. T. Vanderbilt Co.

Anon. (1975) Materials and Cornunding Ingredients for Rubber, NEW York, Bill Communications, pp. 37, 41, 48, 49, 56, 57 Anon. (1976) Alcoholism. Phar. Index, 18, 11

Asmussen, E., Hald, J., Jacobsen, E. & J0rgensen, G. (1948a) Studies on the effect of tetraethylthiurar disulphide (Antabuse) and alcohol on respiration and circulation in nornl hum subjects. Acta pharcol. toxicol. (Kbh.), 4, 297-304

Asmussen, E., Hald, J. & Lasen, V. (1948b) The pharcological action of acetaldehyde on the hum organism. Acta pharcol. toxicol. (Kbh.), 4, 311-320

Bailey, G.C. (1931) Thiurar disulfides. US Patent 1,796,977, Mach 17, to Roessler & Hasslacher Chercal Co.

Brown, M.W., Porter, G.S. & William, A.E. (1974) The deterrnation of disulfirar in bloo, and of exaled carton disulphide using cathode ray polarography. J. Phar. Phamicol., 26, Suppl., 95P-96P Child, G.P. & Cru, M. (1952) The toxicity of tetraethylthuram disulphide (Antabuse) to ITuse, rat, rabbit and dog. Acta pharcoL. toxicoL. (Kbh.), 8, 305-314 Christensen, J. & Wase, A. (1954) Tetraethylthuram disulphide and thyroid activity. Fed. Proc., 13, 343

Dornr, G., Fredga, A. & Linderholm, H. (1949) A rrthod for qutitative deterrnation of tetraethylthuram disulphide (Antabuse, Abtinyl) and its reduced form, diethyldithocarbac acid, as found in excreta. Acta chem. scand., 3, 1441-1442

Eldjar, L. (1950a) The rrtalisr of tetraethyl thurarisulphide (AntabUSi Aversan) in the rat, investigated by ITans of radioactive sulphur. Scand. J. clin. La. Invest., 2, 198-201

Eldjarn, L. (1950b) The rntablisr of tetraethyl thurarisulphide (AntaUSi Aversan) in ma, investigated by rnans of radioactive sulphur. Scanda J. clin. La. Invest., 2, 202-208 Fishbin, L. & Zielinski, W.L., Jr (1967) Chorntography of cabates. Chomat. Rev., 9, 37-101

92 Fitzhugh, O.G., Winter, W.J. & Nelson, A.A. (1952) San observations on the chronic toxicity of antabuse (tetraethylthiurarisulfide). Fed. Proc., Il, 345-346 Goldstein, M. (1966) Inhibition of norepinephrine biosynthesis at the dopane-ß-hydroxylation stage. Pham. Rev., 18, 77-82

Grasselli, J.G., ed. (1973) Atlas of Spectral Data and Physical Constants for Organic Compunds, Cleveland, Ohio, Chcal Rubber Co., p. B-483

Grodzki, M. (1881) Concerning ethylated thioureas. Chem. Ber., 14, 2754-2758 Hald, J. & Jacobsen, E. (1948) The formtion of acetaldehyde in the organsm after ingestion of Antabuse (tetraethyltlliurar disulphide) and alcohol. Acta pharmcol. toxicol. (Kb.), 4, 305- 310 Hald, J., Jacobsen, E. & Lasen, V. (1948) The sensitizing effect of tetraethylthiurarisulphide (Antabuse) to ethyl alcohoL. Acta pharcol. toxicol. (Kbh.), 4, 285-296 Hald, J., Jacobsen, E. & Larsen, V. (1949) Formtion of acetaldehyde in the organism in relation to dosage of Antabuse (tetraethylthiurar disulphide) and to alcohol-concentration in bloo. Acta pharmcol. toxicol. (Kbh.), 5, 179-188

Holck, H.G.O., Lish, P.M., Sjogren, D.W., Westerfeld, W.W. & Malone, M.H. (1970) Effects of disuifiram on grOl, langevity and reprouction of the albino rat. J. pham. Sci., 59, 1267-1270 lAC (1972) lAC Monographs on the Evaluation of Carcinogenic Risk of Chercals to Ma, l, Lyon, pp. 107-124

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petruce1li, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and indus trial chemcals for b:rrrorigenici ty in mice: a prelirnar note. J. nat. Cancer Inst., 42,1101-1114

Johnston, C.D. & Prickett, C.S. (1952) The production of carbon disulfide frc: tetraethylthiuram disuifide (Antause) in rat liver. Biochir. biophys. acta, 9, 219-220 Kaslander, J. (1963) Formtion of an S-glucuronide from tet.raetllylthiurar disulfide (Antause) in ma. Biochir. biophys. acta, 71, 730-732

Lasen, V. (1948) The effect on exrirntal anirls of Antabuse (tetra- ethylthurarisulphide) in corination with alcohoL Acta pharmcoL. toxicol. (Kbh.), 4, 321 - 332

93 Lijinsky, W., Conrad, E. & Van de Boart, R. (1972) Carcinogenic nitro- sarnes fonn by drg/nitrite interactions. Nature (Lond.), 239, 165- 167

Lilly, L.J. (1975) Investigations in vitro and in vivo of the effects of disulfiram (Antause) on hum lymhoce chrorrSOITs. Toxicolog, 4, 331-340 van Loten, M.J. (1972) De Dithocarbaat-Alcohol-Reactie bij de Rat, Terborg, The Nether lands, Bei j f FA. Lars .Mrlevede, E. & Casier, H. (1961) Teneur en sulfure de carbone de 11 air expiré chez des personnes normles ou sous l'influence de 1 1 alcool éthylique au cours du traiternt par l'Antabuse (disulfiram) et le diéthyldithiocarbate de soude. Arch. inL Pharmcodyn., 132, 427-453

Neim, A.H., Coffey, D.S. & Hellerm, L. (1966) Interaction between tetraethylthurar disulfide and the sulfhydrl groups of D-arno acid oxidase and of hemlobin. J. biol. Ch., 241, 5941-5948

NTIS (National Technical Informtion Service) (1968) Evluation of Carcino- genic, Teratogenic and Mutagenic Acti vi ties of Selected Pesticides and Industrial Chemcals, Vol. l, Cacinogenic Study, Washington IX, US Departt of Corrrce

Nygaard, A.P. & Sumer, J.B. (1952) D-Glyceraldehyde 3-phosphate dehydrogenase i a cornrison wi th Ii ver aldehyde dehydrogenase. Arch. Biocher. Biophys., 39, 119-128

Porter, G.S. & William, A. (1972) The detennation of ION concentrations of disulfiram by cathode ray polarography. J. Pham. Pharcol., 24, Suppl., l44P- l45P

Prickett, C.S. & Johnston, C.D. (1953) Th in vivo production of carbon disulfide fram tetraethyIthiuransulfide (Antabuse). Biocir. biophys. acta, 12, 542-546 Richert, D.A., Vanderline, R. & Westerfeld, W.W. (1950) The COition of rat liver xanthine oxidase and its inhibition by antabuse. J. biol. Cher., 186, 261- 274

Schrl, D., Krüger, F.W., Ivanovic, S. & Preissler, P. (1971) Verrnderug der Toxizi-ut von Dimthylnitrosarn bei Ratten und .Musen nach Beand- lung mit Disulfirar. Arzneirttel Forsch., 21, 1560-1562

Schrl, D., Krüger, F. W., Hab, M. & Diehl, B. (1976) Influence of disulfirar on the organotropy of the carcinogenic effect of dirthylnitrosarne and diethylnitrosarne in rats. Z. Krebsforsch., 85, 271 -276

94 Shaver, F.W. (1968) Ruber chercals. ln: Kirk, R.E. & Othr, D.F., eds, Encyclopeia of Chemcal Technolog, 2nd ed., VoL. 17, Ne York, John Wiley & Sons, pp. 509-514

Stecher, P.G., ed. (1968) The Merck Index, 8th ed., Raway, ID, M2rck & Co., p. 393

Ström, J.H. (1963) Inhibition of hexokinase by disulfirar and diethyl- di thiocarba te. Biocher. Pharrcol., 12, 157-166 Ström, J.H. (1965) Metalisrn of disulfirar and diethyldithiocarbate in rats with demnstration of an in vivo ethanol -induced inhition of the glucuronic acid conjugation of the thiol. Biocher. Phacol., 14, 393-410

US Interntional Trade Corrssion (1975) Synthetic Organic Chemcals, US Production and Sales of Rur-Processing Chcals, 1974 Prelirar, Washington IX, US Goernt Printing Office, p. 8

US Tariff Commssion (1941) Synthe tic Organic Chcals, us Production and Sales, 1940, Report No. 148, Secod Series, Washington De, US Govemrt Printing Office, p. 50 Wattenrg, L.W. (1974) Inhibition of carcinogenic and toxic effects of pol ycyclic hydrocarbons by several su) fur-cotaining corrp:mnds. J. nat. Cancer Inst., 52, 1583-1587 Wattenrg, L.W. (1975) Inhibition of dithylhydrazine-induced neoplasia. of the large intestine by disulfirar. J. nat. Cacer Inst., 54, 1005- 1006

Weast, R.C., ed. (1975) CRC Hadbk of Chstr and Physics, 56th ed., Cleveland, Ohio, Chemcal Ruber Co., p. C-272

Wells, J. & Koves, E. (1974) Detection of cabon disulphide (a disulfirar rntalite) in expired air by gas chrortography. J. Chomat., 92, 442-444

Zemitis, M.A. & Greene, F .E. (1976) Imairrnt of hepatic microsornl drg rætalism in the rat during daily disulfiram admistration. Biocher. PharcoL., 25, 1355-1360

95 DULIN

1. Chemcal and Physical Data 1 . 1 Synonyr and trade nas

Cher. Abstr. Reg. Serial No.: 150-69-6

Cher. Abstr. Nar: (4-Ethoxyhenyl) urea

para- Ethoxyheny 1urea; para-phe.netolcarbaide; para-phenetolecarbade; para-phenety 1 urea

Dulcine; Sucrol; Valzin

1. 2 Chercal formla and rnlecular weight

o CH3-CH2-0~NH-C-NH2~II

C9H12N202 MoL. wt: 180.2 1.3 Chemcal and physical properties of the substace

(a) Description: Needles (Stecher, 1968)

(b) Melting-point: l73-l740C (Weast, 1975) (c) Spectroscopy data: Àma 290 nr and 242 nr in ethanol (El = 110 and 1001) (Weast, 1975); for infra-red spectra, 1 see Grasselli (1973).

(d) Solubility: 1 part soluble in 800 parts of cold water, 50 pats of hot water or 25 part of ethaml (Stecher, 1968)

(e) Stability: Partially decoITses on heating with water; hydrolyses in 0.1 N acetic acid (p~chter, 1950)

1.4 Technical products and imuri ties

No data were available ta the Working Group.

97 2. Production, Use, Ocurrence and Anlysis For Í1rtant background informtion on this section, see prearle, p. 15. 2. 1 Production and use

The prepaation of dulcin was first reported in 1883 by Berlinerblau, who synthesized i t by reacting para-phenetidine wi th phosgene and anm:mia

(Stecher, 1968).

Dulcin can be prepared by: (a) reacting para-phenetidine hydrochloride with urea; (e.) heating para-ethoxyhenylurethan and arnia; (c) treating aini ur para-ethoxyheny ldi thocarba te wi th lead caba te; (d) ethy 1 - ating para-hydroxyhenylurea; (e) heating di(para-ethxyhenyl)urea with urea, ainiur carbate and arnium carbonate; or (f) reacting arnia with para-ethoxyhenyl isocanate (Kurzer, 1963).

Conmrcial production of dulcin was reported in the US between 1944 (US Tariff Comnssion, 1946) and 1955 (US Tariff Ccrssion, 1956). "N indication has ben found that it is cuently being produced in conmrcial quantities in the US, although t: cornies produce it for research purses . Dulcin is 250 tirs as swet as sucrose, has a taste preferable to that of sacchain and when used in corination with saccharin ha a synrgistic sweetening effect and enhances the sugar- like flavour (Weinbrg, 1964). The only know use of dulcin was as a non-nutritive sweetener (Stecher, 1968), but it has not ben used as such in the US for over 20 years since it is not approved by the Food and Drug Adrnistration (Sanders, 1953).

ln 1967, the Joint FAO/WO Exrt Ccrttee on Foo Additives recoIn ITnded that dulcin should not be used as a foo additive (WO, 1968). ln Japan, the use of dulcin as a foo additive was forbidden in 1968 (Japanese Union of Foo Additives Associations, 1974).

2 . 2 Occurrence

Dulcin is not kno; to occu as a natural product.

98 2.3 Analysis

Numrous rnthods have been describ for the sepaation and identification of artificial ~etening agents by th- layer chomatogaphy on different substrates and using a vaiety of reagents for their detection.

Dulcin has ben deterrned by thin-layer chronitogaphy in carbona- ted drins and fruit juices, with lirts of detection of 5 and 7 m~lkg, respectively (de la Torre Boronat & Rialta, 1972); in a vaiety of soft drinks, with a lirt of detection of 0.03% (Korbelak, 1969); and in sorn Japanese foos, with a lirt of detection of 1-8 llg/rn (Uchiyam et aL., 1969). A detailed rrthod for its deterrnation in foo products, with a detection lir t ranging fror O. 01-2 ll9 depending on the chorenic spray reagent enloyed, includes a prelirar colum chrortography clean-up (Takeshita, 1972). A comarison has been made of the sesitivity of different spray reagents on different thn- layer chronitography substrates, with detection lirts for dulcin ranging froID 0.1-1.0 ll9 (Nagasawa et al., 1970). Paper chrorrtography has been used for its detection in foo, with a lirt of 12.5 ll9 (Matsuito, 1969), and in wine (Rotolo, 1972). Gas chrortogaphy has æen anloyed ta sepaate the rrthylated derivative of dulcin fror other sweeteners (König, 1971).

3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma

3.1 Carcinogenicity and related studies in anls (a) Oral admstration Rat: Groups of 10 male an 10 femle 4-~ek old Osbrne-I'1endel rats were fed diets containing 0, O. 01, O. l, O. 25, O. 5 or 1 % dulcin for up to 2 years; 25% of the anins receiving 1% dulcin died withn one year. Ten animls recei ving 1% in the diet, 2 recei ving O. 5 % an 1 recei ving O. 1 % developed hepatic-cell adenonis, sorr of which were describd as 'histologically nilignt'. No such tuiurs occurred in rats fed 0.01% dulcin or in those of the control group (Fitzhugh et al., 1951).

99 Groups of 10-25 male rats (strain not specified) were fed diets containing 0, 0.001, 0.01, O. l, 0.5 or 1% dulcin for 2 years. After 18 month, 7/10, 7/10, 7/10, 8/20, 7/20 and 4/25 rats in the respective groups were still alive; no liver tururs vvre observed (Ikeda et aL., 1960).

A group of 30 l4-week old rats (mainly male, strain Ilt specified) was fed 20 g of a diet containing 1% commrcial dulcin (m.p. l69-l700C) daily for up to 24 months. Thirty rats fed the basal diet alone served as controls. All of 30 rats which received a diet containing 0.1% butter yellow and served as positive controls died with liver tururs within 21-24 months. After one year, 26 dulcin-treated rats an 26 controls were alive; by the end of the exrimnt, 9 trated and 13 control rats were still alive. Papillcms of the pelvic epithelium and of the bladder occurred in abut 75% of 23 treated animls and in none of 19 controls. Stones were present in the renal pel vis and bladder of alut 66 % of the 23 treated anls. All stones were associated wi th papillomas, but the papillomas did not always occur in the area of the urinary tract where the stone was located (Bä & Griepetrog, 1958; Griepetrog, 1959).

A group of 80 white rats (sex unspecified) received different doses of dulcin for lifespan. Fifteen rats receiving 0.2 g/kg bw/day surived 12 rrnths, and the last rat survived 22 months; no carcinogenic effect was seen (Lettré & Wrba, 1955).

(b) Oter exprirntal system

Pre- and postnatal exsures: A group of 20 male and 30 ferle rats was given oral intubtions of 0.2 g!kg bw/day dulcin in Twen-rnthyl cellulose solution for 400 days (total dose, 17 g), at which tir 60 % of the anirls were still alive. Half of these animls received no dulcin from then on and were observed until death¡ the remining anirls continued to receive the dulcin treatrt, and total doses of up to 33 g/anirl vvre given. No malignant tururs were reported. Of 30 controls given the 'Ten-rrthyl cellulose vehicle alone, one developed a fibroadenoma. During the exrirnt an unstated nurr of treated males and 20 treated femles vvre mted; the 39 male offspring were treated at 8 vveks of age wi th 0.2 g/kg bw/day for 660 days (total dose, 29 g), at which tim the 5 surivors vvre killed. No malignant tururs vvre reported (Bekerier et aL., 1958).

100 3.2 Oter relevant biological data (a) Exiintal system The oral ID 1 S for dulcin in young and adult rats are 4.9 and 3.2 g!kg 50 bw, respectively (Bekerier et al., 1958). Doses of alut 0.5 g!kg l: dulcin per day were lethal to rats wi thn several days to a few weeks (Bekerier et al., 1958; Lettré & Wrba, 1955).

After its oral admnistration to rats, dulcin is absorbed rapidly (Akagi et aL., 1965; Kojir et aL., 1966) and is distributed thoughout the bcy, wi th highest concentrations in the li ver, kidneys, brain and lungs; tissue levels dirinished to one-tenth within 24 hours after dosing

(Akagi et al., 1965).

Akagi et aL. (1966) found that 3% of a dose of dulcin was excreted unchanged in the urine of treated rabbits, 27% was excreted as dulcin N-glucuronide, a further 40% was excreted collectively as para-hydroxy- phenylurea and its O-sulphate and O-glucuronide, and there were srll aIunts of urinar para-arophenol.

No deleterious effects were seen on the l8th day of gestation in the foetuses of ferle mice given 10-50 rr!kg l: dulcin intragastrically on days 8-10 of pregcy. Retarded growt and sorn deaths were observed arong the progeny of dam treated on days 6-7 of pregncy (Tanaka, 1964).

Dulcin reacts with nitrite to form N-nitrosodulcin (Mirvish, 1975).

(b) Ma

Thorough studies on hur volunteers, including several diabtics, showed that the ingestion of 0.1-0.6 g dulcin/day for one year produced no adverse effects (Rost & Braun, 1926).

'lo death in children have been associated wi th the ingestion of 8-10 g dulcin. ln adults, doses of 20-40 g dulcin produced dizziness, nausea, rnthaerlobinaema with cyanosis, hyptension and, in one case, coronary disturbace (Buh, 1948). 3 . 3 Case reports and epidemological studies

No data were available to the WJrking Group.

101 4. Coimnts on Data Reported and Evluation 4 .1 Animl data Dulcin has ben tested onl y in rats by oral admnistration. Increased incidences of li ver-cel 1 adenoms were obsered in one study, and papillomas of the renal pelvis and bladder, associated with stone formtion, were seen in another study, but these results were rDt confinr in two other trials. No evaluation of the cacinogenici ty of dulcin ca Ce made. 4.2 Hur data

No case reports or epiderological studies were available to the Working Group.

102 5. References

Akagi, M., Oketai, Y. & Uetsu, T. (1965) Studies on fcx additives. IX. Estimtion of p-ethoxyhenylurea in biological rrterials and physio- logical disposition in the animls. Ch. pham. BuL., 13, 1200-1206

Akagi, M., Aoki, 1. & Uemtsu, T. (1966) Studies on foo additives. X. The IDtalisr of p-ethoxyhenylurea in the rabbit. Ch. pham. BulL., 14, 1-9 Bä, F. & Griepetrog, F. (1958) Zur chonischen Toxzität von Ducin (p-Athoxyhenylhartoff) . Naturissenschaften, 45, 390-391 Beemier, H., Hanig, E. & Pfenigsdorf, G. (1958) Zur Kentnis von Vertäglichkeit und Cacerogenität des p-Athoxy-phenylhamtoffes. Arzneirttel-Forsch., ~, 150-151 Buh, G. (1948) Vier Vergiftungsfälle mit de Süssstoff Ducin (para- Phenetolcarbad). Med. Klinik, 43, 105-108

Fitzhugh, O.G., Nelson, A.A. & Frawley, J.P. (1951) A comparison of the chronic toxici ties of sythetic sweetening agents. J. Arr. pham. Ass., 40, 583-586

Grasselli, J .G., ed. (1973) Atlas of Spectral Data and Physical Constants for Organic Compuns, Cleveland, Ohio, Chercal Ruber Co., p. B-985

Griepetrog, F. (1959) Turen der Hamwege und Harsteine in chni- schen Versuchen mit der Süssstoff p-Phenetylcarbad. Arzneirttel Forsch., 9, 123-125

Iked, Y., Omri, Y., Oka, S., Shioda, M. & Tsuzi, K. (1960) Studies on chronic toxicity of dulcin. J. Fd Hyg. So. Japan, l, 62-69 Japanese Union of Foo Additives Asociations (1974) Th Japanese Stadads of Foo Additives, 3rd ed., Tokyo, pp. 11-12 Kojim, S., Ichibagase, H. & 19uchi, S. (1966) Studies on synthe-tic sweetening agents. VII. Absorption and excretion of sodium cyclamte. Cher. pham. Bull., 14, 965-971

König, H. (1971) Trennung, Nachweis W1d Bestimg der ktitlichen Süssstoffe Cyclart, Dulcin und Saccharin mittels CXi-Chorrtographie. Z. analyt. Cher., 255, 123-125

Korbelak, T. (1969) TL identification of four arificial sweeteners in beverages: collabrati ve study. J. Ass. off. anal yt. Chem., 52, 487-491

103 Kurzer, F. (1963) Arlureas. ln: Rajohn, N., ed., Organic Synthe2eS, Vol. 4, New York, John Wiley & Sons, pp. 52-54

Lettré, H. & Wrba, H. (1955) Die Wirkung des Süssstoffes Dulcin bei lang- dauernder Fütterug. Naturissenschaften, 42, 217 Matsumto, S. (1969) Color reactions of sweeteners. ~kyo Toritsu Eisei Kenksho Kenk Ner, 21, 89-92 IiIirvish, S. S . (1975) Formtion of N-ni troso corrunds. Cherstr, kinetics and in vivo occurence. Toxicol. appl. Phacol., 31, 325-351

Nagasawa, K., Yoshidone, H. & An, K. (1970) Separation and detection of synthetic sweeteners by thin- layer chrorntography. J. Chornt., 52, 173- 176

Richter, F., ed. (1950) Beilsteins Handbuch der organischen Chere, 4th ed. , Vol. 13, Syst. No. 1848, pp. 253-254 Rost, E. & Braun, A. (1926) Zur Pharmologie des para-Phenetolcarbads, Dulcin. Arb. Reichsgesundh. Ame, 57, 212-220

Rotolo, A. (1972) Identificazione di alcui edu1coranti sintetici nei vii. Riv. Vitico1. Enol., 25, 301-310

Sanders, H.J. (1953) SWeet but noncaloric. Industr. Eng. Chem., 45, llA, l3A Stecher, P.G. ed. (1968) The Merck Index, 8th ed., Raway, ID, Meck & Co., pp. 399-400

Takeshita, R. (1972) Application of colum and thn-layer chrorntography to the detection of artif icial sweeteners in foos. J. Chornt., 66, 283-293

Tanaka, R. (1964) The toxicity of sythetic sweetening agents to mice emryo. Japan. J. Publ. Hlth, 11, 909-915 de la Torre Boronat, C. & Rialta, C. (1972) Investigación de edulcorantes en beidas del rnrcado, aromticas y no alcohólicas. Circ. Far., 30, 231-242

Uchiyar, S., Kondo, T. & Kawashiro, 1. (1969) A new f1uorortric analysis of dulcin using sodium nitrite. 1. Establisrunt of quantitative rnthod and its application to foo analysis. Yakugaku Zasshi, 89, 828-832

US Tariff Commssion (1946) Sythetic Organic Chercals, us Production and Sales, 1944, Report No. 155, Second Series, Washington OC, US Governt Printing Office, p. 99

104 us Tariff Corrssion (1956) Synthetic Organic Chemcals, us Production and Sales, 1955, Report No. 198, Secod Series, Washington OC, US Gover.t Printig Office, p. 117 Weast, R.C., ed. (1975) CRC Hadbk of Chemstr and Physics, 56th ed., Cleveland, Ohio, Chemcal Rubber Co., p. C-532

Weinbrg, B. (1964) Sweetening chemcals challenge sucrose. Caad. Chem. Processing, April, 77, 80

WHO (1968) Specifications for the identity and purity of foo additives and their toxicological evaluation: soræ flavouring substances and non-nutri ti ve sweetening agents. wid Hl th Org. techn. Rep. Ser., No. 383, pp. 100-103

105 ET SELEC

1. Chercal and Physical Data 1. 1 Synonyr and trade nas

Chem. Abstr. Reg. Serial No.: 12367-47-4 Chem. Abstr. Nar: Tetrakis (diethy lcabai thoato-S.. S' ) selenium

Selenium diethy ldi thiocarbate, tetrakis (diethy ldi thocarbato) - selenium

Ethy 1 selerar

1. 2 Chemcal formula and rrlecular ~ight ~ Il /N-C-5 Se (CHCH3-CH2 3-CH2 S) 4

C20H40N4s8Se !-l. wt: 672.0 1. 3 Chemcal and physical properties of the pure substance

No data were available to the Working Group. 1 . 4 Technical products and imuri ties

Ethy 1 selenac is available cc.rciall y ID the us wi th the following typical specifications: yellow :tder; denity, 1. 32 :: 0.03; rrlting range, 59-850C; rristure (at 40-450C), 2.5% ma.; ash, 0.5% IT.; paticle size, 99.5% passes though a 100-iæsh scree; selenium cotent, 10.5-12.7% (Anon., 1974, 1975). The chercal is also available in a dispersion containing 70% ethyl selenc and 30% ethylene-propylene-dene binder (Anon. 1975).

107 2 . Production, Use, Occuence and .Anal ysis

For imrtant background informtion on this section, see preamle, p. 15. 2 . 1 Production and use

The usual method for the preparation of water-insoluble dialkyldithiocarbate metal salts is precipitation of the rætal salt frar an aqueous preparation of the sodium dialkyldithiocarbate (Shaver, 1968).

Commrcial production of ethy 1 selenac was first reported in the US in 1938 (US Tariff Conmssion, 1939); only one maufacturer reported production in 1974 (US International Trade Conmssion, 1975). It is estirted that less th 1 million kg are produced annually in Franc.

Ethy 1 selenac is usd in the ruber-processing industry as an accelerator to produce desired physical properties in vulcanized ruber in a shorter curing tiI and at lCMr sulphur levels than with conventional accelerators (Supp & Gibbs, 1974). It is used in cornunding natural, butadiene, isobutylene-isoprene and styrene-butadiene rubers. It is an effective accelerator for low-sulphur and sulphur- less heat-resistant cornunds, does not cause discolouration and is generally used with thiazoles to balance scorch and cure characteristics (Anon., 1975).

According ta the US Ocpational Safety am Health Adnistration heal th stands for air contanats, an erloyee' s exosur ta selenium coun shuld rot exceed 0.2 rr/m3 (as Se) in th \\rkplace air during any eight-hour \\rkshift for a fort-hour \\rk wee (US Co of Federal Reations, 1975). ln the USSR, the ma allowable concentration of selenium coun in th work envirorint is 0.1 rr/m3 (Winell, 1975).

2 . 2 Occurrence

Ethyl selenac is not known to occur as a natural product. 2 . 3 Anal ysis

Methods for the deterrnation of selenium by gas chromatography have ben reviewed (Young & Christian, 1973). Gas chrortography coupled with a microwve-emssion spectrometric detection system has ben used for

108 deterrnation of trace arunts of selenium in environmtal samles (Talm & Andren, 1974). Ethyl selenac has been deterrned in ruber additives by bath atomic absorption spetrorætr and v.t analytical deterrnation of selenium (Supp & Gibbs, 1974).

Methods for the chromatographic analysis of cabates, including thiocarbates, have been reviewed (Fishbin & Zielinski, 1967). A thin- layer chrortogaphic-spectrophotofluorirtric ræthod (va Hoof & Heyndrickx, 1973) is suitale for the analysis of a variety of rrtal dithiocarbamtes, al though i t was not applied to ethy 1 selenac i tself .

3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Hem 1

3.1 Carcinogenici ty and related studies in animls

(a) Oral admistration

Mouse: Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F mice and 1 18 male and 18 femle C57BL/6xA)F mice received commrcial ethyl selenac 1 (m.p. 59-850c) according to the follONing schedule: 10 TI/kg bt in gelatine at 7 days of age by storch tub and the sar anunt (not adjusted for increasing boy weight) daily up to 4 weeks of age; subseqently, the nuce were given 26 mg ethyl selenac per kg of diet. The dose was the ma tolerated dose for infant and young rnce but rit necessarily so for adults. The exprimnt was terrnated when the animls v.re alut 78 v.eks of age, at which tir 16, 14, 17 and 14 mice in the four groups, respectively, were still ali ve. Tiur incidences were cornared wi th those in 79-90 necropsied mice of each sex and strain, which either had been untreated or had received gelatine onl y . Tuurs occured in 16/18 riropsied males (12 hepatos, 3 reticulum-cell sarccs an i sebacus-glarr cacina). of the first strain am

1 See also the rrnogaph on selenium and selenium cOITunds (IA , 1975) . 109 in 5/17 males (3 hepatomas, 1 reticulurcell sarco and 3 pulna tuuurs) and 4/17 fErles (3 reticulurcell sarCOS and 1 pulInar turur) of the second strain. The increased incidence of hepator in (C57BL/6x C3H/Anf)F males over tht in controls (12/18 corred with 8/79) was 1 significant (P~O.OOl) (Innes et al., 1969; NTIS, 1968).

(b) Subtaeous admistration

!-use: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F rnce and 18 male and 18 femle (C57BL/6xA)F rnce v.re given single S.c.1 injections 1 of 464 IT!kg li ethyl selenac (m.p. 59-850C) in 0.5% gelatine on the 28th day of life and were observed until they were abut 78 v.eks of age, at which tim 13, 17, 18 and 18 mice in the four groups, resptively, were still ali ve . 'lur incidences were c:ed wi th those in groups of 141, 154, 161 and 157 untreated or vecle-injected contrIs that were necropsied. Incidences were not increased (P:?0.05) for any turur ty in any sex-strain suboup or in the cained sexes of either strain (NTIS, 1968) (The Working Group note that a negative result obtained with a single s.c. injection may not be an adeqte bais for discounting cacinogenicityJ. 3.2 Oter relevant biological data

No data were available to the Working Group. 3. 3 Case reports and epidemological studies

No data were available to the V'rking Group.

4 . Cots on Data Reported and Evaluation 4 . 1 Animl data

Etyl selenac has be tested by oral admistration and by single sutaus injecion in tw strain of rnce. It produced an increased incidence of liver-cell tururs in rrles of one strain but did Ilt significantl y increase the incidence of tUIurs m the other. Th available data are insufficient to allow an evaluation of the carcinogenicity of ths ~und to be made.

110 4. 2 Hur data

No case reports or epidemological studies ~re available to the Working Group.

111 5. References

Anon. (1974) Etyl Selenc (I , Norwalk, Connecticut, R. T. Vanderbilt Co. Anon. (1975) Materials and Camunding Ingredients for Ruber, Ne York, Bill Communcations, pp. 51, 53 Fishbin, L. & Zielinski, W.L., Jr (1967) Chorntogaphy of cabamtes. Chrornt. Rev., 9, 37-101 van Hoof, F. & Heyndrickx, A. (1973) Thn layer chorntogaphic-spectro- photophuorÌItric rrthods for the deterrnation of ditho- and thiol- carbamtes after hydrolysis and coupling with NBD-Cl. Ghent. Rijks- univ. Fac. Ladbl. Med., 38, 911-916 IA (1975) lAC !-nographs on the Evaluation of Cacinogenic Risk of Chemcals to Ma, 9, Sorn Aziridines, N-, S- and O-Mustads and Selenium, Lyon, pp-: 250-251

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrucelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for turrigenici ty in mice: a prelirar note. J. nat. Cancer Inst., 42, 1101-1114

NTIS (National Technical Informtion Service) (1968) Evluation of Carcinogenic, Teratogenic and Mutagenic Activities of Selected Pesticides an Industrial Chcals, Vol. l, Carcinogenic Study, Washington DC, US Depatrt of Comærce

Shaver, F.W. (1968) Ruber chemcals. ln: Kirk, R.E. & Othr, D.F., ed, Encyclopeia of Chemcal Technolog, 2nd ed., VoL. 17, New York, John Wiley & Sons, p. 513

Supp, G.R. & Gibbs, 1. (1974) The deterration of selenium and tellurium in organic accelerators used in the vucanization process for natural and synthe tic rubers by atomic absorption spectroitr. Atamic Absorp tion Newslett., 13, 71-73

Talm, Y. & Andren, A.W. (1974) Determnation of selenium in environIntal sanles using gas chrortography wi th a micrcwave emssion spectroitric detection system. Analyt. Che., 46, 2122-2126

US Code of Federal Reguations (1975) Air Contamants, Title 29, pat. 1910.1000, Washington De, US Governnt Printing Office, p. 61 US International Trade Commssion (1975) Synthetic Organic Chercals, US Production and Sales of Rubber- Processing Chemcals, 1974 Prelirnar, Washington DC, US Governnt Printing Office, p. 7

112 US Tariff Commssion (1939) Synthe tic Organic Chcals, US Proouction and Sales, 1938, Report No. 136, Secod Series, Washigt OC, US Governt Printing Office, p. 45 Winell, M.A. (1975) An international ccarison of hygienic stadads for chemcals in the work environrt. Anio,.!, 34- 36 Young, J.W. & Christian G.D. (1973) Ga-chromtogaphic deterration of selenium. Analyt. chir. acta., 65, 127-138

113 EI TEC

1. Chemcal and Physical Data 1. 1 Synonyr and trade nars

Cher. Abstr. Reg. Serial No.: 12367-49-6

Cher. Abstr. Nam: Tetrakis (diethylcarbaithoato-B,S') telluriur

Tellurium diethyldithiocarbate 1 . 2 Chercal formula an rrlecular ~ight

~ N-C-SIl Te (CH:rCH2CH3-~ S j4

C20H40N4s8Te MoL. wt: 720.6 1. 3 Chercal and physical properties of th pure substace

No data were available to the Vbrking Group. 1 . 4 Technical products and iruri ties

Ethyl tellurac is available corcially in the us with the fOllOling typical speifications: orange-yellow r:er; density, 1. 44 :! 0.03; rnlting range, 108-1l80C; paicle size, 100% passes though a 3O-rrsh screen; ash, 2.5% ma.; tellurium content, 17.5-19.5%; heating loss, 1. 0% ma. (Anon., 1968). For ruber processing, ethl tellurac is available in rod form containing 80% of active ingredient and in a dispersion containing 25% of a binder (Ann., 1975).

2. Production, Use, Occurrence and Anysis

For Imrtat background inforntion on ths section, see prearle, p . 15.

115 2. 1 Production and use Ethyl tellurac can be prepared by the addition of cabon disulphide to an aqueous solution of diethylarne and sodium hydroxide (Shaver, 1968), followed by reaction of the resulting sodium diethyldithocarbat-e with potassium tellurite (Husebye & SVaeren, 1973). Corrcial production of ethyl tellurac was first reported in the US in 1939 (US Tariff Commssion, 1940); only one us maufacturer reoorted production in 1974 (US International Trade Commssion, 1975). Les:= tIian 1 million kg are produced anually in the Beelux countries and in France.

Ethy 1 tellurac is used in the ruber-processing industry as an accelerator in comundig natural, styrene-butadiene f ni trile-butadiene, ethylene-propylene diene and isobutylene-isoprene rubers. It produces high-rrulus vucanization and is generall y used wi th thazole m:ifiers

(Anon., 1975). 2 . 2 Occuence

Ethyl tellurac is not knC1 to occur as natural product. 2 . 3 Anal ysis Ethy 1 tellurac in ruber addi ti ves can be deterred by atorc absorption spectrartric or gravitric deterrnation of tellurium (Supp & Gibbs, 1974). Method for the chrorrtographic analysis of carbamtes, including thiocarbates, have been reviewed (Fishbin & Zielinski, 1967). A thin- layer chrantogaphic-spectrophotofluorimtric rrthod (van Hoof & Heyndrickx, 1973) is suitale for the anlysis of a variety of rntal dithocbartes, although it was not applied to ethyl tellurac itself.

3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma 3. 1 Carcinogenici ty and related studies in aniinals (a) Oral admstration

!-use: Groups of 18 rrle and 18 femle (C57BL/6À'C3H/An)F rnce and 1

116 L8 male and 18 femle (C57BL/6xA)F rnce received commcial ethyl 1 tellurac (m. p. 108- l180C) accordig to the followng schedule: 46.4 ff!kg hw in gelatine at 7 days of age by starch tub and the sai arunt (not adjusted for increasing l:y weight) daily up to 4 v.eks of age; subseqently, the mi ce were given 149 ff ethyl tellurac per kg of diet. The dose was the maÌImnn tolerated dose for infant and young rnce but not necessarily sa for adul ts. The exprirnt was terrated when the an:ils were abut 78 weeks of age, at which tir 15 rrles and 18 femles of each strain were still alive. Tuur incidences were cornred with those in 79-90 necropsied mice of each sex and strain, which either had be untreated or had received gelatine only. Tuurs developed in 9/16 necropsied rrles and in 2/18 necropsied femles of the first strain and in 6/18 necropsied maes and 6/18 necropsied femles of the second strain. Hepatomas occured in 4/16 males of the first strain and in 3/18 males of the second strain, corned with 8/79 and 5/90 in controls (P:?O. 05 for each strain). Th incidence of lung tuiurs in males and femles of the second strain was 7/36, comped with 12/172 in controls (P~0.02J (Innes et al., 1969; NTIS, 1968).

(b) Subcutaeous admistration

fvuse: Groups of 18 rrle and 18 ferle (C57BL/6xC3H/An)F rnce and 1 18 male and 18 ferle (C57BL/6xA)F mice v.re given single s.c. injections 1 of 1000 ff!kg bN ethyl tellurac (m.p. 108-ll80C) in 0.5% gelatine on the 28th day of life and were observed until they were abut 78 weks of age, at which tir 14, 17, 17 and 15 mice in the four groups, respectively, v.re still alive. Tuur incidences were coed with those in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. Incidences were not increased (P:?O. 05) for any tuiur ty in any sex-strain subroup or in the cornined sexes of ei ther strain (NTIS, 1968) (The Working Group noted that a negative result obtained with a single s.c. injection rry not te an adeqate basis for discounting carcinogenici ty J .

3.2 Other relevant biological data

No data were available to the Working Group.

117 3. 3 Case report an epidemological studies

NJ da ta were available to the W:rking Group.

4. Comnts on Data Reported and Evluation 4 . 1 Animl data

Ethyl tellurac has ben teste by oral admistration and by single subtaeous injection in tw strains of mice. There wa a smll but significant increase in t. mmibr of lung tuiurs in rrles and feres of one strain corined after its oral admstration. Th available data are insufficient to allow an evaluation of the cacinogenicity of this cornund. 4 . 2 Hur da ta

No case reports or epidemological studies were available ta the Working Group.

118 5. References Anon. (1968) Etyl Tellurac (E , Ne York, R. T. Vanderbilt Co.

Anon. (1975) Materials and Corunding Ingredents for Rubber, Nev York, Bill Commcations, pp. 47, 51, 54 Fishbin, L. & Zielinski, W.L., Jr (1967) Chortogaphy of cabates. Chromat. Rev., 9, 37-101 van Hoof, F. & Heyndrickx, A. (1973) Th layer chomatogaphic-spetro- photc:huorimtric ræthods for the deterrnation of ditho- and thol- carbates after hydrolysis and coupling with NBD~i. Ghnt. Rijks- univ. Fac. Ladbl. l1., 38, 911-916

Husebye, S. & SVaeren, S.E. (1973) Th crystal and rrlecuar strcture of tetrakis (diethyldithiocbato) tellurium (IV). Acta chem. scand., 27, 763-778

Innes, J .R.M., Ulland, B.M., Valerio, M.G., Petrcelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Fal, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for turrigenici ty in mice: a prelirar note. J. nat. Cacer Inst., 42,1101-1114

NTIS (National Techncal Inforntion Service) (1968) Evluation of Carcinogenic, Teratoenic and Mutagenic Acti vi lies of Selected Pesticides and Industrial Chcals, Vol. l, Cacinogenic Study, Washington De, US Departt of Comærce

Shaver, F. w. (1968) Ruber checals. ln: Kik, R. E. & Ot:r, D.F., ed, Encyclopeia of Chemcal Tecolog, 200 ed., Vol. 17, Ne York, John Wiley & Sons, p. 513

Supp, G.R. & Gibbs, 1. (1974) 'Te deterrtion of selenium and tellurium in organic accelerators used in the vucaization process for natural and synthetic rurs by atamic absorption spectartr. Atoc Aborp tion Newslett., 13, 71-73 US Interntional Trade Corssion (1975) Synthetic Oranc Chcals, US Production and Sales of Rub-Procssing Chcals, 1974 Prelirar, Washigton De, US Goverrt Printing Office, p. 7

US Tariff Corrssion (1940) Sythetic Organic Chcals, US Production and Sales, 1939, Report No. 140, Second Series, Washigt OC, US Govenut Printig Office, p. 45

119 FER

1. Chemcal and Physical Data 1 . 1 Synonyr and trade ris

Chem. Abstr. Reg. Serial No.: 14484-64-1 Cher. Abstr. Nai: Tris(dimthylcarbaithoato-S-,S')iron

Dimthy lcarbami thioic acid, iron conplex; dimthy lcarbari thoic acid, iron ( 3+) salt; dimthy Idi thiocarbac acid, iron salt; dimthyldithiocarbarc acid, iron (3+) salt; ferric dimthylditho- carbarte; iron dimthyldithiocarbate; tris (dithyldithiocarbarto)- iron; tris (N-, N-dithyldithiocarbato) iron (III) Aafertis; Bercem Fertai 50; Ferba 50; Ferba, iron salt; Ferbek; Ferrte; Ferrte Ferba fungicide; Ferradcw; Fuklasin Ultra; Hexaferb; Kaba Black; Stauffer ferba; Sup'r Flo Ferbar Flcwable; Trifungol; Vancide FE-95 1.2 Chemcal formla and irlecular weight ~ 1\ / N-C-S Fe ( CH3CH3 S 3) C9H18FeN3S6 MoL. wt: 416.5 1.3 Chemcal and physical properties of the substace

From Stecher (1968), unless otherwise spcified

(a) Description: Black solid

(b) Melting-point: Abve l800C (decomsition)

121 1.4 Technical products an iruri ties

Ferba is available in the US as dusts containing 0.6-25% of the chemcal, as \Vttale ¡:ers contanig 3-98% and as a flo.able formation containing 42%. ln Japa, ferba is available as a technical product containig at least 95% of the chemcal (Japanese Miistr of Agriculture & Forestr, 1975).

2. Production, Use, Ocurence and Analysis

For imrtat background informtion on ths section, see prearle, p. 15.

2.1 Production an use

Ferba was first prepaed and evaluated as a fugicide in abut 1931 (Tisdale & William, 1934). It can be prepared by the reaction of dimthyl- amne wi th cabon disulphide in the presence of soum hydroxide follo.ed by addition of a ferric salt, such as feric chloride (Kent, 1974). Ths is believed to be the rnthod used in the corcial production of ferba.

Ferba has been produced corcially in the US since 1945 (US Tariff Corrssion, 1947). US production reached a ma level of 1.4 million kg in 1961 (US Tariff Corrssion, 1962); in 1968, the last year for whch production quti ties were reported, O. 8 million kg ferba \Vre produced (US Depart of AgriculJcure, 1972); in recent years, only 1 or 2 cor- panies have produced it. Total US exrts of all dithocarbate formlations were 6.7 million kg in 1974 (US Deart of Carce, 1975). Ferbar is produced by one cay in Th Netherlands (Beg, 1975); one producer in France and one in the OK have an estirted total anual production of less th 1 million kg.

One compy in Japan bean producing ferba in 1970. The qutity produced has decreased fran 28.6 thousand kg in 1970 to only 700 kg in 1974 (Japanese Ministr of Agriculture & Forestr, 1975).

ln the US, ferba is used as a fungicide to control diseases of plants, paricularly those affecting apples and tobacco (Berg, 1975), and 1S registeed for use on alut 75 agricutural and ornamtal plants (US Environ-

122 rrntal Protection Agency, 1973). ln :!971, 356 thousand kg were used on agricultural crops in the US (US Depart of Agriculture, 1974).

ln Euope, ferba is utilized as follOts: fungicide (80 %), ruber accelerator (19%) and plastics pro-degradant (1%). ln Japa, it is used on apples and ci trs fruts (Japanese Miistr of Agriculture & Forestr, 1975) . A residue tolerance of 7 IT/kg has ben estalished in the US for alut 60 raw agricultural coties (US Code of Federal Reglations, 1974), and may US corities rny bear residues of ferba approaching ths level. Acrding ta the US OXationa Safety am Heal th Admnistration heal th stanrd for air contamnats, an emloyee' s exsur ta ferb should rot exæed 15 m;/m3 in the tMrkplace air during ai- eight-hour tMrkshift for a forty-hour we (US Coe of Fedral Reations, 1975). ln Deerr 1974, the Joint Meeting of the FAO Working Party of Exrts on Pesticide Residues and the WHO Exprt Conttee on Pesticide Residues estalished a revised temrar acceptale daily intae for ma of 0-0.005 IT/kg bw for aIl dithiocarbamte fungicides (WHO, 1975a,b). 2. 2 Occurence

Ferba is not known to occu as a natural product. For informtion on the levels of ethy lenethiourea , a possible breakdow product, that may be found on raw agricultural products, see IA (1974). As part of the 'Total Diet Progar' of the US FCX and Drug Adis- tration, 360 compsite foo sanles ~re collected anually during the peiod 1964-1970, prepared as for consurtion and anlysed for dithiocarbate content. A ma of 4 cosi tes contained detectale levels of dithiocabates in any single year (Corneliussen, 1972), and in at least one year no dithocarbate was detected. On the basis of these results, analysis for dithocarbates in ths programe was discontinued after 1970 (Maske & Corneliussen, 1974).

2.3 Analysis

Methods for the chromatogaphic analysis of carbates, including dithocbate pesticides, have been reviewed (Fishbin & zielinski, 1967).

123 Ferba residues have been detemiined by polarography, ",ii di a sensitivity of 80 lJg/rn (Supin et al., 1973) or of 10-7 M (Budikov et al., 1974). The voltatric beaviour of ferba has also èeen studied (Golding et al., 1974) and might provide the basis for an analytical rrthod. A rapid colorimtric rnthod for the estimtion of ferba residues on grains allows recveries of 91-100% at levels of 10-1000 lJg (Rangaswam et al., 1970) .

3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma

3.1 Cacinogenicity and related studies in anirls

(a) Oral admistration

!-use: Groups of 18 m:le and 18 fenle (C57BL/6XC3H/Anf)F rnce and 1 18 m:le and 18 fenle (C57BL/6xA) F mice reived carcial fei: (97% 1 pure) according to the follCMng schedule: 10 rr/kg hv in gelatine at 7 days of age by stanch tub an the sa arunt (not adjusted for increasing boy weight) daily up to 4 weeks of age; subseqently, the mice were given 32 mg ferba per kg of diet. The dose given was the rr tolerated dose for infant and young rnce but not necessaril y sa for adul ts . Th exrimt was tennted when the animls were alxmt 78 wees of age, at which tire 16, 16, 16 an 15 mice in the four groups, respetively, were still alive. 'Iur incidences were cared with those observed arng 79-90 necropsied mice of each sex and strain, which either had be untreated or had received gelatine only: th incidences were not significantly greater (P::O.05) for any tUIur ty in any sex-strain suboup or in the cornined sexes of ei ther strain (Innes et al., 1969; NTS,1968).

Rat: Four groups of 25 4-væek old rats of each sex v.re fed 0, 25, 250 or 2500 mg ferba per kg of diet for 2 years. Controls lived for 600-700 days; rnian length of surival arng rats given either 25 or 250 mg ferba per kg of diet was not altered, whereas at the highest dose lifespan was alut 430 days. Thre v.re 12 tururs in treated animls, and 7 in control rats; these were reported to be unelated to dose. Tuur sites were not indicated (Hodge et aL., 1956).

124 (b) Subutaeous admnistration

Mouse: Groups of 18 rnle and 18 femle (C57BL/6xC3H/An)F Mce and 18 male and 18 femle (C57BL/6xA)F rnce were given single s.c.1 injections 1 of 100 rn/kg bw comnrcial ferbar (95% pure) in 0.5% gelatine at 28 days of age and were observed until they were abut 78 v.eks of age, at which ti 15, 17, 18 and 16 mice inthe four groups, respetively, were still alive. Tuour incidences were cornared with those in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. Incidences were not increased (P:?0.05) for any turur ty in any sex-strain subgroup or in the combined sexes of either strain (NTIS, 1968) (The Working Group noted that a negative result obtained with a single subutaneous injection rny not be an adeqate basis for discounting cacinogenici ty J .

3.2 oter relevant biological data

(a) Exrimtal system

ln short- and long-terr feeding studies in rats gi ven diets containing 25-2500 rn/kg ferbar, apart from non-neoplastic brain changes in rats given the highest dose, no adverse effects were seen (Hodge et al., 1952, 1956).

Approxirtely 40-70% of an oral dose of ferba was absorbed fram the gastrointestinal tract of rats during a 24-hour period. ln rats that received 35S-ferbar, 18% of the 35S was excreted in the exaled air as carbon disulphide and 23% in the urine. ln those given (dithyi_14CJ- ferba, 43% of the radioactivity was found in the urine as dirthylarne and dimthyldithiocarbamte glucuonide (Hodgson et aZ., 1975).

The combinat ion of ferba wi th ethanol caused accumlation of acetaldehyde in tlie blcx (van Loen, 1972). Ferbar reacts with nitrite to forr N-nitrosodimthylarne (Sen et aL., 1974).

When pregnant rats were dosed with (dithyi_14CJ-ferbam, a smll amunt ofradioactivity crossed the placenta and accumlated in the foetuses. Radioactivity was also secreted into the milk of lactating rats given (dimthyi-14CJ-ferbar and was in turn e.xcreted in the urine of the pups (Hodgson et aZ., 1974, 1975).

125 Admnistration of 150 rr/kg hA/day ferba to pregt rats on days 6- 15 of gestation caused sone foetal death, increased resorption, decreased foetal weight and produced a slight increase in the numr of ans wi th soft and skeletal tissue abnormlities (Mior et ai., 1974).

Prasad & Prarr (1968) reporte colour rmtats and reverse rmtations in Aspergiiius niger; rætalic activation system were not use in these tests. (b) Ma

No data were available to the Working Group, but for a discusion of the interaction of cornunds such as ferbam with ethol in the bloo, see 'General Remks on Carbates, Thiocarbartes and Carbazides', pp. 28-29. 3. 3 Case reports and epidemological studies

No data were available to the Workig Group.

4. Coimts on Data Reported and Evluation

4.1 Animl data

Ferba has ben tested by oral admistration in rnce and rats and by single subtaneous injection in mice. Although no cacinogenic effect was obsered in these tests, the available data are inufficient for an evaluation of the carcinogenici ty of ths comp:mnd to be made.

Ferba can react with nitrite under mildly acid conditions, sirting those in the hum stanch, to forr N-nitrosodirthylame, whch ha ben shaw to be carcinogenic in seven anl spies (IA, 1972). 4 . 2 Hum data

No case reports or epidemological studies were available to the Working Group.

126 5. References

Berg, G.L., ed. (1975) FarChecals Handlk 1975, Willoughby, Ohio, Meister, p. D93

Budnikov, G.K., Toropova, V.F., Ulakovich, N.A. & Viter, I.P. (1974) Electrochemcal bevior of dithocbates on a rrrcu electrcxe. III. Polarographic study of fungicides of dithocbate ty in organic solvents. Zh. anlyt. Kh., 29, 1204-1209

Corneliussen, P .E. (1972) Pesticide residues in total diet samles. Pest. Moni t. J., 5, 313- 330 Fishbin, L. & Zielinski, W.L., Jr (1967) Chamtogaphy of cabates. Chamt. Rev., 9, 37-101

Golding, R.M., Letonen, K. & Ralph, B.J. (1974) Voltatr of tris (N~N- diorgancxithiocbato) iron (III) colexes in acetone. J. inorg. nucL. Cher., 36, 2047-205Ó

Hcxge, H.C., Maynard, E.A., Dos, W., Blanchet, H.J., Jr & Jones, C.K. (1952) Acute and short-tem oral taxicity tests of ferric diithyl- dithiocarbate (Ferba) and zinc dimthyldithocbate (zirar). J. Arr. pham. Ass., 41, 662-665

Hcxge, H.C., Maynard, E.A., Dos, W.L., Coye, R.D., Jr & Steadm, L.T. (1956) Chronic oral toxicity of ferric dithyldithocarbate (Ferba) and zinc dimthyldithocrbarte (Ziram). J. PhacoL. ex. Ther., 118, 174- 181

Hcxgson, J.R., Castles, T.R., Murrill, E. & Le, C.-C. (1974) Distribution, excretion and rrtalisr of the fungicide ferba in rats. Fed. Proc., 33, 537

Hcxgson, J.R., Hoch, J.C., Castles, T.R., Helton, D.O. & Le, C.-C. (1975) Metalisr and disposition of ferba in the rat. Toxicol. appl. PharcoL., 33, 505-513 IAC (1972) IA Monogaphs on the Evaluation of Cacinogenic Risk of Chemcals ta Ma, l, Lyon, pp. 95-106 lAC (1974) IAC !-nographs on the Evluation of Cacinogenic Risk of Chemcals ta J'1a, 2, Sorr Anti -thyroid and Related Substaces, Nitrofurans and Industrial Chemcals, Lyon, pp. 45-52

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrucelli, L., Fishbin, L., Har, E.R., Pallotta, A.J., Bates, R.R., Fal, H.L., Gart, J.J., Klein, M., J'titchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for tuirigenci ty in mice: a prelirar note. J. nat. Cacer Inst., 42, 1101-1114

127 Japanese Ministry of Agriculture and Forestry (1975) Noyaku Yoran (Agri- cultural Chercals Anual), 1975, Division of Plant Disease Prevention, Tokyo, Takeo Endo, pp. 17, 18, 20, 267, 268, 275 Kent, J .A., ed. (1974) Riegel' s HandJk of Industrial Chemstr, 7th ed., New York, Van Nostrand-Reinhold, pp. 634-635 van Loen, M.J. (1972) De Dithocarbaat-Alcohol-Reactie bij de Rat, Terborg, The Ne the r lands, Bei j f FA. Lars, p. 40

Maske, D.D. & Corneliussen, P.E. (1974) Pesticide residues in total diet samles. VII. Pest. Monit. J., 8, 110-114 Minor, J. L., Russell, J. Q. & Le, C. -C . (1974) Reproduction and teratolog studies wi th the fungicide ferba. Toxicol. appl. Pharncol., 29, 120

NTIS (National Technical Informtion Service) (1968) Evluation of Carcino- genic, Teratogenic and Mutagenic Activities of Selected Pesticides and Industrial Chemcals, Vol. l, Carcinogenic Study, Washington IX, US Deparnt of Conmrce

Prasad, 1. & Pramr, D. (1968) Geetic effects of ferbar on AspergiZlus niger and A Z Zium cepa. Phytopatholog, 58, 1188-1189 Ragaswam, J.R., Poornir, P. & Majurer, S.K. (1970) Rapid colorimtric rnthod for estimtion of ferba and ziram residues on grains. J. Ass. off. analyt. Cher., 53, 1043-1044

Sen, N.P., Donaldson, B.A. & Chbonneau, C. (1974) Formtion of nitroso- diithylarne fror the interaction of certain -psticides and nitrite. ln: Boovski, P. & Walker, E.A., eds, N-Nitroso Corm:::unds in the Environrt, Lyon, IA (lAC Scientific Pulications No. 9), pp. 75-79 Stecher, P .G., ed. (1968) The Merck Index, 8th ed., Raway, ID, Merck & Co., p. 451 Supin, G.S., Klisenko, M.A. & Vekshtein, B.S. (1973) Polarographic deter- mination of residual arunts of fungicide as di thiocarbonic acid derivatives. Khim. SeL. Khoz., 11, 840-842

Tisdale, W.H. & William, 1. (1934) Disinfectant. US Patent 1,972,961, Septemr 11, to E. 1. du Pont de Nerurs and Co.

US Coe of Federal Reglations (1974) Protection of Environrt, Title 40, par. 180.114, Washington De, US Governnt Printing Office, PP. 248-249

US Coe of Federal Regulations (1975) Ai Contarnants, Title 29, par. 1910.1000, Washington IX, US Governmt Printing Office, P. 61

US Depart of Agriculture (1972) The Pesticide Review 1971, vJashington IX, US Governnt Printing Office, p. 18

128 US Depart of Agriculture (1974) Farrs' Use of Pesticides in 1971, Quanti ties , Economic Research Service, Agricul tural Economic Report, No. 252, Washington DC, US Governt Printing Office, p. 25 us Depart of Commrce (1975) US Exrts, PT 4101, Deemr 1974, Bureau of the Census, Washington IX, US Govemnnt Printing Office, pp. 2-135- 2- 136 US Envirorital Protection Agency (1973) EPA Candium of Reistered Pesticides, Vol. Ii, Fungicides and Nerticides, Washington IX, US Governt Printing Office, par. 1, pp. F-OI-00.Ol-F-Ol-OO.10

us Tariff Commssion (1947) Synthe tic Organic Chercals, us Production and Sales, 1945, Report No. 157, Second Series, ~tJashington De, US Goverrnt Printing Office, p. 186

US Tariff Commssion (1962) Sythetic Organic Chemcals, us Production and Sales, 1961, TC Pulication 72, Washington IX, US Governnt Printing Office, p. 166

ì'fO (1975a) 1974 Evaluations of sorr æsticide residues ln foo. Wld Hlth Org. Pest. Res. Ser., No. 4, pp. 261-263

ì\1O (1975b) Pesticide residues in fcx. :Repxt of the 1974 Joint ~.-eting of the FAO Working Party of Exrts on Pesticide Residues and the ~l'O Exrt Commttee on Pesticide Residues. Wld Hlth Org. techn. Rep. Ser., No . 574, pp. 26- 2 8

129 LEATE

1. Checal and Physical Data 1 . 1 Synonyr and trade nas

Chem. Abstr. Reg. Serial No.: 19010-66-3

Chem. Abstr. Nam: Bis(dithylcabamithoato-S,S')lead Lead dirthy ldi thocarbate 1. 2 Chemcal forrla and rrlecular \æight

'" Il /N-C-S Pb (CHCHi i S 2J

C6H12N2PbS 4 ~1oi. wt: 447.6 1 . 3 Chercal and physical propeies of the pure substance

No data were available to the Working Group. 1. 4 Techncal praducts and imuri ties

Ledate pcer is available ccrciall y ln the US wi th the follONng specifications: white p:er; density, 2.43 :! 0.03; paticle size, 99.9% passes though a 100-meh screen; lead content, 45.5-47.5%; rrlting-point, abve 3L00C; rristure (at 100-1050C), 1% ma. (Anon., 1975a).

For ruber processing, ledate is available ccrcially in the US in the forr of rads with sirlar spifications (Ann., 1975b). It is also available as a paste with 30% light oil and as a dispersion with 25% polyisobutylene binder (Anon., 1975a).

131 2. Production, Use, Occurrence and Anal ysis

For imrtant background informtion on this section, see preamle, p. 15.

2 . 1 Production and use Ledate can be prepared from lead acetate and potassium dimthyldithiocarbarte (LA, 1972; Jensen et al., 1971). Commrcial production in the US was first reported in 1934 (US Tariff Commssion, 1936); ln 1974, only one maufacturer reported production (US International Trade Cormssion, 1975). It is estirted that less than 1 million kg are produced anually in the Benelux countries, ltaly and the OK.

Ledate is used in the ruber-processing industr as an accelerator for high-sped, high-temerature vulcanization. It is used ln cornunding natural, styrene-butadiene, isobutylene-isoprene, isoprene and butadiene rubbers. It is effective under continuous cuing conditions and is generally used with thiazole mofiers (Anon., 1975a). 2. 2 Occurrence Ledate is not know ta occu as a natural product.

2.3 Analysis

Methods for the chromtographic anal ysis of carbartes, including thiocarbates, have been reviewed (Fishbin & Zielinski, 1967) A thin- layer chrorntographic-spectrophotofluorimtric method (van Hoof & Heyndrickx, 1973) is suitable for the analysis of a variety of metal dithiocarbates, a1though it was not applied to ledate itself. An investigation of the electrochemcal beaviour of metal di thiocarbates, including ledate, has ben reported (Budnikov et al., 1974).

132 3. Biological Data Relevant to the Evluation of Carcinogenic Risk ta Ma 3.1 Carcinogenicity an related studies in a.s

(a) Oral admistration

Mouse: Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F rnce and 18 male and 18 ferle (C57BL/6xA)F mice received commrcial ledate1 1 (m.p. ?3l00c) according to the following schedule: 46.4 ng/kg l: in gelatine at 7 days of age by storch tub and the sam amunt (not adjusted for increasing boy weight) daily up to 4 W2ekS of age; subseqently, the mice were gi ven 130 mg ledte per kg of diet. The dose was the maimum tolerated dose for infant and young mice but not necessaril y so for adults. The exprirnt was terrated when the anirls were abut 78 weeks of age, at which tim 16, 16, 17 and 18 rnce in the four groups, respecti vel y, were still ali ve. Tuur incidences were corned wi th those in 79-90 necropsied mice of each sex and strain, which had be untreated or had received gelatine only. Tuurs develope in 7/16 necropsied males (1 malignt lyrhoma, 1 hepatoma, 5 reticulum-cell sarcomas) and 1/18 necropsied ferles (1 lxme tUIur) of the first strain and in 2/17 males (2 pulnnar adenoms) of the second strain. The incidence of reticulumcell sacoms in males of the first strain was significatly different from that in controls (5/16 versus 5/79) (P~O.OlJ (Ines et al., 1969; NTIS, 1968).

(b) Subutaneous admnistration

!-use: Groups of 18 male and 18 feme (C57BL/6xC3H/An)F rnce and 18 male and 18 ferle (C57BL/6xA)F rnce W2re given single s.c.1 injections 1 of 1000 ffg/kg hw comrcial ledate (m.p. ?3l00C) in 0.5% gelatine on the 28th day of life and were observed until they were alut 78 weks of age, at which tir 15, 18, 18 and 15 mice in the four groups, respectively, were still ali ve. Tuur incidences were comped wi th those in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. Incidences were not increased (P?O.05) for any tUIur ty in any sex-strain subroup or in the conbined sexes of ei ther strain (NTIS, 1968) (The Working Group noted that a negative result obtained

133 with a single S.c. injection may not te an adeqate basis for discounting carcinogenici ty J .

3.2 Other relevant biological data

No data were available to the Working Group. 3. 3 Case reports and epidemological studies

No data were available to the Working Group.

4. Conits on Data Reported and Evluation 4. 1 Animl data

Ledate has been tested by oral admistration and by single subutaneous injection in two strains of mice. Although an increase in the incidence of reticulumcell sarcors was observed in mIes of one strain follcwing oral admnistration of the compund, the available data are insufficient for evaluation of its carcinogenicity. 4 . 2 Hum data

No case reports or epidemological studies were available to the Working Group.

134 5. References

Anon. (1975a) Materials and Corunding Ingredients for Ruber, Ne: York, Bill Commcations, pp. 42, 49, 51 Anon. (1975b) Ledate CI , Color Rodfonn CI , Norwalk, Connecticut, R. T. Vanderbilt Co.

Budnikov, G.K., Ulakovich, N.A., Viter, 1.P. & Kolesnikova, L.V. (1974) Effect of the adsorption of a depolarizer on the polarogaphic reduction of rntal dithocarbates in organic solvents. J. gen. Cham. (USSR), 44, 730-737 Fishbin, L. & Zielinski, W.L., Jr (1967) Chomtogaphy of cabartes. Chrort. Rev., 9, 37-101 van Hoof, F. & Heyndrickx, A. (1973) Thn layer chronitographic-spectrophotofluorimtric rrthods for the deterrnation of ditho- and thiolcarbates after hydrolysis and coupling with :ND-Cl. Ghnt. Rijks- univ. Fac. LadbL. Me., 38, 911-916 lAC (1972) lAC !-nogaphs on the Evaluation of Cacinogenic Risk of Chemcals to Ma, 9, Sar Aziridines, N-, S- and O-Mustads and Selenium, Lyon~ pp. 40-50

Innes, J .R.M., Ulland, B.M., Valerio, M.G., Petrucelli, L., Fishbin, L., Ha, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gat, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for turrigenici ty in mice: a prelirar note. J. nat. Cancer Inst., 42,1101-1114 Jensen, K.A., Dahl, B.M., Nielse, P .H. & Borch, G.(197l) Tentative assigrt of fundarntal vibrations of tho- and selenocarboxylates. II. The dimthyldithocarbate ion. Acta chem. scand., 25, 2029-2038

NTIS (National Techncal Informtion Serice) (1968) Evluation of Carcino- genic, Teratogenic and Mutagenic Acti vi ties of Sp-lect.ed Pest.icides and Industrial Chemcals, Vol. l, Carcinogenic Study, Washington IX, US Depatrnt of Comærce US Interntional Trade Corssion (1975) Synthetic Organic Chcals, US Production and Sales of Rubber- Processing Chercals, 1974 Prelirnar, Washington DC, US Governnt Printing Office, p. 8

US Tariff Commssion (1936) Oyes and OtherSynthetic Organic Chemcals in th US, 1934, Report No. 101, Second Seies, Washington OC, US Governt Printing Office, p. 66

135 MAB

1. Chemcal and Physical Data 1 . 1 Synonym and trade nas

Chem. Abstr. Reg. Serial No.: 12427-38-2

Chem. Abstr. Nare: 1:1, 2-Ethanediylbis (carbaithoato)) (2-) 1- rnganese 1,2-Ethanediylbiscarbaithoic acid, maganese corrlex; 1,2- ethanediylbiscarbathioic acid, maganese (2+) salt (1: 1) ; 1,2-ethediylbisreb, rnganese (2+) salt (1: 1); ethylenebis (dithio- carbato), rnganese; ethylenebis (dithiocrbarc acid), maganese sal t; l, 2-ethy lenedi y lbis (carbami thioato) maganese; rneb ; rnganese ethy lene bisdi thiocarba te

Chloroble M; Dithane M22; Dithane M-22 Sp2cial; Kyprn 80; Maeb 80; Maeba; Maeban; Maesan; Mazate; Mazate D; Polyram M; Rhodianebe; Sopraneb; Sup IR Flo; Trimgol; Vancide Maeb 80 1. 2 Chemcal fonna and rrlecular ~ight

HN-CH2-CH~H CI./s" Mn ¿s~1 C '\~,,/5 5

C4H6lvnN2S4 MoL. wt: 265 . 3 1.3 Chemcal and physical properties of the substace

From Stecher (1968), unless otherwise specified

(a) Description: Crystals from ethanol

(b) Melting-point: Decompses l:fore rælting (Association of Amrica Pesticide Control Officials, Inc., 1962)

137 (c) Solubility: M:erately soluble in water¡ soluble ln chloroform and pyridine 1. 4 Technical products and imuri ties

.Meb is available in the us as a ~ttale :¡der, containing 80 % of the chemcal, and in formlations, which also contain a smll arunt of an inorganic zinc salt (Berg, 1975).

.My comnrcial ethylenebisdithiocbarte sales, including mneb, contain ethylenethourea (EI) (Bontoyan et aL., 1972). Bontoyan & Loker (1973) studed the initial ET contents of various ethylenebisdithocar- bamte products and the levels after storage at 880C. Th initial Er content in speific formulations of 'rrneb, 80%' vaÌE:~d betwn 0.05 and 1.26% ¡ after 39 days of storage ET levels vaied between 0.58 and 14.54 %.

2. Production, Use, Occurrence and Anlysis

For imrtat background informtion on ths section, see preale, p. 15. A review on rneb has be published by the US Envirorital Protection Agerc (1974).

2.1 Production and use Maeb ca be prepaed by the reaction of ethylenediarne wi th cabon disulphide in the presence of soium hydroxide to produce the sodium salt, which is then treated with a rnganese salt (e.g., mnganese sulphate) to precipitate rneb (US Environrtal Protection Agency, 1974). Mab was introduced as an agricultural fungicide in the us in 1950. 'lo US cornes produced an estimted 5.5 million kg of rneb in 1972, and exprts wee estimted ta be 2 million kg (US Environrntal Protection Agency, 1974). It is also produced in Israel and in The Netherlands (Berg, 1975) ¡ 1.5 million kg are estited ta be prcucd annually in l:th Fran ar ltay, an less thn 1 million kg each in th Fedral Republic of Genn, Spin and the UK.

ln Japan, production of rneb was started in 1964 ¡ tw coIlanies now pi:uce it, and in 1974 protion rehed a level of 1.9 million kg.

138 Irrts fror France, Israel, Th Netherlands and the US arunted to alut 800 thousand kg in 1974, dow from abut 900 thousand kg in 1973. There have ben no exprts from Japa since 1972 when minor quantities ~re exprted to India, Korea, The People's Republic of China, Taiwan and Thailand (Japaese Ministr of Agriculture & Forestry, 1975).

Maeb is used exclusively as a broad spetr contact fungicide and 1S registered for use on over 46 crops in the US. Th principal diseases controlled by maeb are early and late blight of potato and tornto, dONY mildew and anthacnose on a nunr of vegetales and the so-called 'rot' diseases of fruts such as apricots, peaches and grapes. It is also used for seed treatrt of smll grains, such as wheat (US Environmntal Protection Agency, 1974).

ln 1971, 1. 7 million kg were used on us agricultural crops (US Depabænt of Agriculture, 1974); in 1974, of abut 70 thousand kg used in Californa, one third was on head lettuce (California Depart of Foo & Agricuture, 1975). ln ltaly, an estimted 2 million kg are utilized anually. ln Japa, over half of the 2.1 million kg maeb used in 1974 was used on paddy-field rice, alut one-thrd was used on citr fruts, and the reminder was used on nelons and vegetales (Japanese Ministry of Agriculture & Forestr, 1975).

Residue tolerances on raw agricultural products in the US are generally in the range of 2-10 mg/kg, with the exceptions of 0.1, 15 and 45 rr/kg for alm:mds and r:tatos, bas an sugar-bet taps, respetively (US Code of Federal Regations, 1974). ln Decerr 1974, the Joint Meting of the FAO Working Party of Exs on Pesticide Residues and the WHO Exprt Cc: ttee on Pesticide Residues established a revised terrar acceptale dail y intae for ma of 0-0.005 rn/kg hw for all dithocarbate fungicides (WO, 1975a,b). 2. 2 Occurence Maeb is not knaw to occu as a natural product. As part of the 1 Total Diet Prograr' of the US Foo and Drug Adni- stration, 360 cOIsite foo samles ~re collected anually during the

139 period 1964-1970, prepaed as for consurtion and analysed for dithocarbate content. A ni of 4 cosi tes contained detectable levels of dithocarbates in any single year (Corneliussen, 1972), and in at least one year, no dithiocarbate was detected. On the basis of the se results, analysis for dithiocabates in this program was discontinued after 1970 (Maske & Corneliussen, 1974). The signficance of rneb as a residue on agricultural products is enhanced by reports that the coking of fcxs containing ethylenebisdithocarbate residues v.uld result in degradation to forr ET; thus, cokin) of vegetales containing residues of rneb near the tolerance level would result in the formtion of ET (Blazquez, 1973; Watts et al., 1974). For informtion on the levels of ET which can be found on raw agricultural products, see IAC (1974).

2.3 Analysis Thee reviews which include ræthods for the anal ysis of rneb have been published (Fishbin, 1975; Fishbin & Zielinski, 1967; Zweig & Sherm, 1972). Maneb has ben deterrned following i ts hydrol ysis wi th hydrochloric acid containing staous chloride; the resulting ethylenediarne is recovered on an ion-exchange colum and deterrned by gas chrortogaphy as the bis-trifluoroacetate. The lir t of detection was 0.1 rr/kg (Newsoræ, 1974). A screening procedure has been developed for dithiocarba-- mate residues in foo invol ving head-space anal ysis of the cal:xm disulphide produced on hydrol ysis. The carbon disulphide was detened by gas chromatography, using a flai photortric detector. Reveries of maeb added to sarles at the 7 :r/kg level were 70-95% (McLe & McCully, 1969). Carbon disulphide formtion with a colorimtric end deternnation (Keppel, 1969) was used by Yip et al. (1971) ta deterrne rneb residues in field- sprayed lettuce and kale and by Howard & Yip (1971) to study the staility of maneb, zineb and Dithane M-22 added to kale. Polarogaphic nethods have also been used: Budnikov et al. (1974) showed that-7 10 M levels of rnarse coun can be detei:ne.

140 Stevenson (1972) has describ a test based on the colour developed by acid di thzone, which depeds on the ty and concentration of netal present. However, the presence of a di thiocbate mut be estalished separatel y, using conventional procedures.

3. Biological Data Relevant to the Evaluation of Carcinogenic Risk to M3

3.1 Carcinogenicity and related studies in animls

(a) Oral admnistration

Mouse: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F rnce and 1 18 male and 18 femle (C57BL/6xA)F mice received corcial maeb (96% 1 pure) according to the following schedule: 46.4 rr!kg lM in gelatine at 7 days of age by stomach tub and the sar arunt (not adjusted for increasing body weight) dail y up to 4 weeks of age; subseqentl y, the mice were gi ven 158 mg rneb per kg of diet. Th dose was the na tolerated dose for infant and young mice but not necessarily so for adults. Th exprimt was terrnated when the anls were abut 78 weeks of age, at which ti 16, 15, 18 and 18 mice in th four groups, respectively, were still alive. Tuur incidences were cornred wi th those observed arng 79-90 necropsied mice of each sex and strain, which either had ben untreated or had received gelatine only: the incidences were not signficatly greater (P:?0.05) for any typ of turur in any sex-strain suroup or in the cornined sexes of either strain (Ines et al., 1969; NTIS, 1968).

A group of 200 C57BL mice was given 6 weekly admistrations of rneb by stomach tub, each dose corresponding to 500 rr!kg lM. The mice were killed at intervals of up to 9 m::mths; of 42 suivors killed at 9 rrnths, 4 had lung adenoTIBs. The incidence in untreated controls was 0/44 (P:?O. 05) . Anng sirlarly treated strain A mice, 23/42 had lung adenorns after 9 months, compared with 12/45 controls (p~O.Oli (Balin, 1970). Rat: Of 60 randombred rats given twice weekly doses of 335 mg/kg l: rneb (82.6% pure) in water by stomach tub for lifespan, 6 were still alive after 22 months; 1 rat develope a subutaeous rhabornosarcoma and another a rn carcinorr. One fibrosarcc: was observed arng 46 untreated control rats still alive after 22 Ilnths (Anrianova & Alekseev, 1970). 141 (b) Subutaeous admistration

!-use: Groups of 18 male and 18 ferle (C57BL/6XC3H/An)F rnce and 18 male and 18 femle (C57BL/6xA)F mice v.re given single s.c.1 injections 1 of 100 rnjkg lM cc:rcial rneb (96% pure) in 0.5% gelatine on the 28th day of life and were observed until they were abut 78 v.eks of age, at whch tim 17, 18, 18 and 17 mice in the four groups, respecti vel y, were still ali ve. Tuur incidences were corned wi th those of groups of 141, 154, 161 and 157 untreated or vehcle-injected controls tht were necropsied. Incidences were not increased (P?O. 05) for any turur ty in any sex-strain suboup or in the cornined sexes of either strain (NTIS, 1968) (The Working Group noted that a negative result obtained with a single s.c. injection ffy not be an adeqate basis for discounting carcinogenici ty ) .

Rat: Of 48 random-bred rats given single s.c. injections of 12.5 ID/kg hw rneb (82.6% pure) in paaffin, 4 wee still al ive after 22 rrnth, and 3 develope malignant tururs (2 fibrosarcors and 1 thyroid carcinor) . One fibrosarca was seen in 46 control rats whch did not receive paaffin pellets and were still alive at 22 m:mths (Anianova & Alekeev, 1970). 3.2 Oter relevant biological data (a) Exrimtal system The oral ID of rneb in mice is 4.1 g/kg hw; that in rats has be !: 0 report as 4.5 gjkg l: (Engst et al., 1971) and 6.7 g/kg l: (Berg, 1975). Maneb intoxication increased thyroid function in rats (Ivanova et aL., 1967; lvaova-cemshanska et al., 1971).

ln rats, 55% of an oral dose of l4C-rneb was excreted in the urine and faeces (36% in the urine) within 3 days. After 24 hours, th boy organs contained 1. 2% of the dose as rneb netali tes, and on day 5, less than 0.18%; ethylenediame, ethylenebisthiurar nonosulphide and El were present in the urine and faeces (Seidler et al., 1970) (Th authors do not appear to have mesured pulnnary excretion, which is likel y to account for much of the reminder of the dose).

Maneb (1) (Schere 1) is hydrolysed by acids into ethylenediame (2) and carn disulphide 1 an ths rection may tae place unr the acid

142 SCH i

HN-CH2-CHr-H

L...S" / S~ 1 H+. r CH2NH2J2 +CS2 C~/"/ SMn SC!C CI

r1::=:-:_:J SO.2- l 1"Hl 5 J

H S ~ L " N CH2/N-C \ . ~~: C=S +CS2 CH21 S/ CH2/ ~N_C ~N L " 1 H S H

CD ~

143 conditions of the stornch, accounting for sorn of the carbon disulDhide that is excreted in exhaled air; the rerinder arises from the transfor- mation of ethylene bisthiuram rnnosulphide (3) into ET (4). Sem of the absorbe (2) would be oxidized to glycine and oxalic acid and, ultimtely, to carbon dioxide. The rest of the ethylenediarne (2) is excreted in the urine, together with (4) and inorganic sulphate, but ethylene bisthurar rnnosulphide (3) is excreted in the faeces (Seid1er et al., 1970).

Groups of 10 male and 10 ferle rats were gi ven 1. 4 g/kg bN or 700 mg/kg bN rneb twice weekly for 4~ rnnths. There was a m:erately high incidence of stil1birth and of imrfect skull developrnt, but the actual numrs corred with those aing controls is not stated (Kaloyanova et al., 1967).

Ferle rats were given 50 Irq/kg bN as a suspesion in rnlk on every other day during pregnancy; increased nurrs of emryonic deaths, resorptions, stillbrn young and neonates incapable of survi val were observed. The unfavourable effect of rneb on the course of gestation was a~parent in 21% of pregnancies, cOITared with a 12% bakgroun of untowd events aing the control animls. ln addition, imture ferle and male rats (80- 100 g bw) were adrnistered 50 mg!kg bN/day for 1 rrnth. After 2~ rnnths, control males were mated wi th exsed ferles and vice versa. A decline in fertility was observed in both sexes, but this effect was reversible within 3~ month (Marcon, 1969).

When single oral doses of l, 2 or 4 g!kg bw were admnistered to pregant rats on day 11 or 13 of pregnancy, congenital abnorrlities were induced in 12-100% of the foetuses; no congenital abnorr1ities were observed with 0.5 mg!kg bN (Petrova-Vergieva & lvaova-Chershanska, 1973). Sirlar tests with rneb have been made by Shtenrg et al. (1969) and by Antonovich et al. (1972).

A slight increase in the nurr of chrornsomal abrrations in rreta- phases of bone-rnrow cells was observed in mice treated wi th 100 rn/kg bw orally (Antonovich et ol., 1971).

(b) Man

No data were available to the Working Group.

144 (c) Carcinogenici ty of rntali tes ET ( 4) (Schem 1) produced thyroid carcinomas in rats and increased the incidence of li ver-cell tururs in two strains of mice after i ts oral admnistration (lAC, 1974). 3 . 3 Case reports and epiderological studies

No data were available to the Working GrOUD.

4. Corrnts on Data Reported and Evaluation

4.1 Animl data Maeb has been tested in mice and rats by oral adrctÌist:cation and by single subcutaneous injection. Its oral admnistration produced an increased incidence of lung tururs in mice of one strain, but no increase was observed in thee other strains. The studies in rats caot te evaluated due to the smal1 numrs of suri ving animls. No eva1uation of the carcinogenici ty of this cornund can be made. 4.2 Hur data

No case reports or epiderological studies were available to the Working Group.

145 5. References

Andrianova, M.M. & Alekseev, LV. (1970) On the carcinogenic properties of the pesticides sevine, rneb, ciram and cineb. Vop. Pi tan., 29, 71-74 Antonovich, E.A. Chepynoga, O.P., Chernov, O.V., Rjazanova, P .A., Vekshtein, M. S., Matson, V. S., Matson, L. V., Sash, L. V., Pilinskaya, M.A., Kurinny, L.I., Balin, P.N., Khtsenko, 1.1., Zastavnjuk, N.P. & Zaolorozhnaja, N .A. (1971) Toxicity of dithocarbates and their fate in warnlooed anlils. ln: Antonovich, E.A., Bojanovska, A., Engst, P. et aZ., eds, Proceeings of the Symsium on Toxicolog and Analytical Chemstr of Dithocarbartes, Durovnic, 1970, Berad, pp. 3-20

Antonovich, E.A., Chernov, O.V., Sarsh, L.V., M:tson, L.V., Pilinskaya, M.A., Kuriny, L.1., Vekshtein, M.S., ~1ason, V.S., Bain, P.N. & Khitsenko, 1.1. (1972) A compative toxicological assessmet of dithiocbates. Gig. i Sanit., 50, 25-30

Association of Amrican Pesticide Control Officials, Inc. (1962) Pesticide Chemcals Official Compndium, Box RH, University P .0., College Park, Maland, p. 193 Balin, P.N. (1970) Exrimntal data on the blastoirenic activity of the fungicide rneb. Vrach. Delo, 4, 21-24 Berg, G.L., ed. (1975) Far Chemcals Handbk 1975, ~lilloughby, Ohio, Meister, p. D 124

Blazquez, C.H. (1973) Residue deterration of ethylenethourea (2-ir- dazolidinethone) from torto foliage, soil and water. J. agric. Fd Chem., 21, 330-332

Bontoyan, W. R. & Loker, J. B . (1973) Deradation of comærcial ethy lene bisdithocabate formulations to ethylenethourea under elevated terrature and hurdi ty. J. agric. Fd Chem., 21, 338-341

Bontoyan, W.R., Loker, J.B., Kaiser, T.E., Giang, P. & Olive, B.M. (1972) Surey of ethylenethourea in cocial ethylenebisdithocarbate fonrlations. J. Ass. off. analyt. Chem., 55, 923-925

Budnikov, G.K., Toro¡x)Va, V.F., Ulakovich, N.A. & Viter, 1.P. (1974) Electrochemcal beavior of di thiocarbarnates on a nercu electrode. III. Polarogaphic study of fungicides of dithocarbanate ty in organic solvents. Zh. analyt. Kh., 29, 1204-1209 ealifornia Depart of Foo and Agriculture (1975) Pesticide Use Report, 1974, Sacramnto, pp. 96-98

146 Corneliussen, P .E. (1972) Pesticide residues in total diet sarles. VI. Pest. Mbnit. J., 5, 313-330

Engst, R., Schnaak, W. & Leerenz, H.-J. (1971) Untersuchungen ZlI Meta- bolisrus der fungiciden Athylen-bis-dithocarbarte Maeb, Zinen und Nab. V. Zur Toxikologie der Abbauprodukte. Z. Lesr ttel. Unter- such., 146, 91-97

Fishbin, L. (1975) Chomatography of Environmtal Hazards, VoL. 3, Pesticides, Amterda, Elsevier, pp. 676-692 Fishbin, L. & Zielinski, W .L., Jr (1967) Chorntography of carbates. Chomat. Rev., 9, 37-101

Howard, S.F. & Yip, G. (1971) Staility of rntallic ethylene bisditho- carbamtes in chopped kale. J. Ass. off. analyt. Chem., 54,1371-1372 IA (1974) lAC !-nogaphs on the Evluation of Cacinogenic Risk of Chemcals to Ma, 2, Sorn Anti-thyroid and Related Substaces, Nitro- furans and Industrial Chemcals, Lyon, pp. 45-52

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrucelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gat, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for turrigenicity in rnce: a prelirar note. J. nat. Cancer Inst., 42, 1101-1114 Ivanova, L., Sheytaov, M. & Mosheva-Izrrova, N. (1967) Chages in the functional state of the thyroid gland upon acute intoxication with certain dithiocarbartes, zineb and maeb. C.R. Acad. Bulg. Sei., 20, 1011-1013

Ivanova-Chershanska, L., Makov, D.V. & Dahev, G. (1971) Light and electron microscope observations on rat thyroid after admistration of sor dithiocarbamtes. Environm. Res., 4, 201-212

Japanese Ministry of Agriculture and Forestr (1975) Noyaku Yoran (Agri- cultural Chemcals Anual) 1975, Division of Plant Disease Protection, Tokyo, Takeo Endo, pp. 18, 21, 85, 86, 89, 101, 265, 266, 281

Kaloyanova, F., Ivanova, L. & Alexiev, B. (1967) The influence of large doses of maeb on the progeny of albino rats. C.R. Acad. Bulg. Sci., 20, 1109-1112 Keppel, G.E. (1969) Moification of the carbon disulfide evolution rnthod for dithiocarbamte residues. J. Ass. off. analyt. Chem., 52, 162-166

Maske, D.D. & Corneliussen, P.E. (1974) Pesticide residues in total diet samles. VII. Pest. Monit. J., 8, 110-114 Macon, L. V . (1969) The effect of rneb on the emryonal develoPIt of generative function of rats. Farol. i Toksikol., 32, 731-732

147 McLeod, H.A. & lvully, K.A. (1969) Head space gas procedure for screening foo sarles for dithiocarbartes pesticide residues. J. AsS. off. analyt. Chem., ~, 1226-1230 Newsor, W.H. (1974) A rrthod for deterrning ethylenebis (dithiocarbarte) residues on foo crops as bis (trifluoroacetado)ethane. J. agric. Fd Chem., 22, 886-889

NTIS (National Technical Infonntion Service) (1968) Evaluation of Carcino- genic, Teratogenic and Mutagenic Acti vi ties of Selected Pesticides and Industrial Chemcals, Vol. 1, Carcinogenic Study, Washington IX, US Departmnt of Commrce

Petrova-Vergieva, T. & Ivanova-Chemshanka, L. (1973) Assessrnnt of the teratogenic activity of dithiocarbate fungicides. Fd Cosrrt. ToxicoL., 11, 239-224

Seidler, H., Härtig, M., Schnaak, W. & Engst, R. (1970) Untersuchungen t.r den Metalisrus einiger Insektizide und F'gizide in der Ratte. II. Verteilung und Abbau von 14C-rnkiertem Maeb. Die Nahg, 14, 363-373

Shtenbrg, A.I., Kirlich, A.E. & Orlova, N.V. (1969) Toxicological characteristics of rneb used in trea tmnt of foo crops. Vop. Pi ta., 28, 66-72

Stecher, P.G., ed. (1968) The Merck Index, 8th ed., Raway, NJ, t1erck & Co., p. 642

Stevenson, A. (1972) A simle color spot test for distinguishing between rneb, zineb, rncozeb, and selected mixtures. J. Ass. off. anal yt. Chem., 55, 939-941

US Code of Federal Regulations (1974) Protection of Environrnt, Title 40, part. 180.110, Washington DC, US Governent Printing Office, p. 247 US Departmnt of Agriculture (1974) Fanrs' Use of Pesticides in 1971, Quanti ties, Economic Research Service, Agricul tural Ecnomic Report No. 252, Washington DC, US Governt Printing Office, p. 25

US Environrntal Protection Agency (1974) Production, Distribution, Use and Environmtal Imact Potential of Selected Pesticides, Office of Pesticide Program, EPA 54011-74-001, Washington IX, US Governnt Printing Office, pp. 298-307

Watts, R.R., Storherr, R.W' & On1ey, J.H. (1974) Effects of coking on ethlenebisdithiocarbamte degradation to ethylene thourea. Bull. environm. Contar. Toxic01., 12, 224-226 iVHO (1975a) 1974 Evaluations of sor pesticide residues in foo. Wld Hlth Org. Pest. Res. Ser., No. 4, pp. 261-263

148 WHO (1974b) Pesticide residues in foo. RefXrt of the 1974 Joint Meeting of the FAO Working Party of Exprt on Pesticide Residues and the WHO Exprt Comm ttee on Pesticide Residues. Wld Hl th Org. techn. Rep. Ser., No. 574, pp. 26-30

Yip, G., Onley, J.H. & Howard, S.F. (1971) Residues of rneb and ethylene thiourea on field-sprayed lettuce and kale. J. Ass. off. analyt. Chem., 54, 1373-1375

Zweig, G. & Sherm, J. (1972) Dithiocarbartes. ln: Z~ig, G., ed., Analytical Methods for Pesticides and Plant Growt Regators, Vol. 6, Gas Chromatographic Anlysis, New York, Academc Press, pp. 561-563

149 ME11 c:..BA'I

1. Chemcal and Physical Data 1.1 Synonyr and trade nas

Chem. Abstr. Reg. Serial No.: 598-55-0 Chem. Abstr. Nam: Cabac acid, nethyl ester Methylureth¡ nethylurethane¡ urethylane

1.2 Chercal fo:rla and rrleclar weight

o Il H2N-C-O-CH3

C2H5N02 .l'b1. wt: 75 . 1

1.2 Chemcal and physical proorties of the substace

From Weast (1975), unless otherwise specified

(a) Description: Neeles o (b) Boiling-point: l770C at 760 Im¡ 82 C at 14 nm

(d) Refractive index: ng6 1. 4125

(e) Solubility: Soluble in water (217 pats in 100 at 11oC), ethanol (73 pars in 100 at l50C) and ether (Prager & Jacobson, 1921)

1.4 Technical products an imuri ties

No data were available to the Working Group.

2. Production, Use, Occuence and Anlysis

For imrtant background informtion on this section, see prearle, D. 15.

151 2 . 1 Production and use

~~thYl carbarte was first prepared by the reaction of cyanogen chloride with methYl alcohol by Echevarria in 1851 (Prager & Jacobson, 1921). It can be made by the reaction of urea with rrthanol at elevated terratures using the following catalysts: zinc oxide-phosphoric acid (Vishnyakova et nl., 1969), lead oxide (Hata, 1970), alumnosilicate (Vishnyakova et al., 1971) or phosphoric acid (Slater & Cureth, 1971). It can also be prepared by the reaction of amnia with methyl chloroformte (Prager & Jacobson, 1921), and this rnthod is believed to have been used commrcially.

Commrcial production of rnthyl carbarte \vas first reported in the US in 1959 (US Tariff Commssion, 1960). ln 1972, an estirted 350 thousand kg were produced by one maufacturer. ln 1973 only two maufacturers reported production (US International Trade Commssion, 1975). Anual production of rrthyl carbate in Euope is estirted to be 0.75 ta 1 million kg.

Methyl carbarte is used as an intenædiate in the maufacture of dirthylol rnthyl carbate-based resins which are used in the textile industr as durable-press fabric finishes for polyester/cotton blends. Such resins, used principally for treating white cloth, have goo crease angle_ 'tention, resist acid souring in commrcial laundries and do not retain chlorine, if properly cued (Hill, 1967). ln Euope, rrthyl carbarte is also used as a oharceutical intermdiate. 2 . 2 Occurrence

Methyl carbarte has been isolated from four Salsola spcies (Karawya et al., 1972).

2.3 Analysis

Methods for the chromatographic anal ysis of carbartes, including alkyl carbartes, have been reviewed (Fishbin & Zielinski, 1967).

A gas chromatographie method for detection of rncrograr amunts of methyl carbamte in a mixture of alkvl carbartes after the formtion of their trirthylsilyl derivatives has been describd (Nery, 1969). Another gas chromatographic method invol ves the use of an alkali fusion detector,

152 in which the arunt of the sar:nification product, rrthanol, is deterred. This procedure has been used for deterring carbates, eid1er singly or in mixtures, at the 0.01-0.1 ~ level (Ladas & Ma, 1973).

Coloriitric methods have ben used to detennne rrthyl cabarte ID air, at a sensitivity of 20 llg/l (Babina, 1975). Thn- layer and chromatographic rnthods have also been used for its detennnation (Karawya et al., 1972; Knappe & Rohdewald, 1966).

3. Biological Data Relevant to the Evaluation of Carcinogenic Risk to Mc

3.1 Carcinogenicity and related studies in anirls

(a) Subcutaneous admistration JVuse: An unspecified numr of randorrbred mle rnce received 3 s.c. injections of 1 rn!kg bN nethyl carbamte at 2-day intervals, and were obsered for 3 mnth, or 3 s.c. injections of 0.1 mg!kg li rrthYl carba- mate, and were observed for 6 lInths. Of those observed for 3 rrnths (first experimt), 3/29 mice killed had lung adenoms, comped with 3/22 controls and with 23/27 mice given 1 rn/kg lM urethaæ plus 1 rn/kg hw rnthyl carbate. Of those observed for 6 mnths (second exrirt) , 2/26 mice killed had lung adenomas, compared with 0/26 controls and with 6/28 rnce given urethane plus rnthyl carbate (Yaguv & Suvalova, 1973).

(b) Intraperitoneal admnistration

Mouse: A group of 46 10-12-week old strain A mice (approxitely e:l numrs of each sex) received 13 v.ekly i.p. injections of 0.5 rr/g recrystallized rnthyl carbate in water; the rnce V\re killed 2-3 V\eks after the final injection, when they were 6 rrnth old. Lung adenomas v.re found in 16% (mean, 0.19 per lIuse), whereas 17% of 141 untreated controls (rnan, 0.18 per muse) develope these tunurs. ln two other groups of 43 and 49 mice injected weekly with doses of 1 and 2 rr/g rrthyl cabate, tUIur incidences were 9 and 22%, respectively, and average nurrs of tururs pe mouse were 0.09 and O. 29 . Doses of 3 rrl g induced ea 1 y deaths (Lasen, 1947).

153 A group of 16 7-9-wee old male A/He mice was given 12 injections of 5 mg/animl in water over 4 w=s and killed 20 w=s after the end of treatmt. Ony lung adenom incidences were reported: 1 lung adenoma was found in 1/16 surivors, conied with 6 lung adenomas in 6/31 mice given the solvent alone and 2 in 2/31 which received no treatrnt (Shiin et al., 1969).

!-use: A group of 20 7-9-wee old male 'S' mice received 15 weekly cutaneous applications of a 25% solution of ltthyl carbate in acetone (total dose, 1. 12 g). Thee days after the sta of the nethyl cabate treatmt, 18 weekly applications of croton oil (0.3 ml of a 0.5% solution in acetone) were given. Eighteen mice were still alive at the end of the croton oil treatint, at which tim they ~re killed: 1/18 develope a skin ti.ur, coned with 1/20 controls given croton oil only. ln addition, 7 mice recei ving rnthy 1 carbate and croton oil had a total of 12 lung adenomas. l' control group killed at the sam tim is reported (Roe & Salam, 1955). (d) Oter exprimtal system

Subutaneous injection plus skin proition: Groups of 40 7-wee old male Hall mice were given single s.c. injections of 40 Il IDthyl cabate in saline followd 2 'Aeks later by 24 ~ekl Y skin applications of croton oil (0.075% in acetone), or were left untreated. A control group of 80 mice recei ved croton oil onl y . All animls suri ved until the end of the croton oil treatmt, when observation was discontinued. Tw epiderl tUIurS (unspecified) were found in 1/25 mice receiving IDthyl cabate plus croton oil¡ none were seen in 28 IDthyl carbarte-injected mice¡ and 3 occured in 2/41 mice receiving croton oil only (Pound, 1967).

Injection plus skin proition: ~ groups of 27 and 30 7-wee old male Hall mice were given a single injection (route not specified) of 27 rng hw rrthyl carbate. Eighteen hours l:fore treatint those in the second group received an application of 0.25 ml of a 0.075% croton oil solution in acetone over the whole area of the skin of the back. Thee wee later, bath groups were gi ven a course of 32 wel Y treatrnts

154 with croton oil, each application consisting of 0.24 ml of an acetone solution, the concentration of which was 0.075% during the first 18 weeks and was then increase to 0.15% for a furer 14 v;eks. A cx:mtrol group of 90 mice received croton oil alone. The nurs of skin tuiur-bearing animIs at 36 week were 8/86 controls, 8/28 in the first group (P.(0.02) and 2/25 (3 tuiurs) in the second. ln animls which died or were killed between 36 and 78 wees, incidences of skin tuiurs, hepators, liver haemgiors, lung adenors and leukaemas v;re sirlar in the two expri- mental groups and in controls recei ving croton oil alone (Pound & Lason, 1976) . 3. 2 Oter relevant biological data (a) Exrimntal system

ln mice, the oral ID of iæthy 1 carbate 1S 6.2 g!kg li (Sri valova, 50 1973) .

The rate of metaJ:x.üisr of intraperitoneally injected rrthyl carbate 1S approxitely one-half tht of ethyl carbate (urethane) (Boyland & Papadopoulos, 1952; IA, 1974). Rats injected intraperitoneally with rnthy 1 carbate or the correspondig N-hydroxycararte excreted bath

the carbate and N-hydroxycarbate in the urine (Boy land & Ner, 1965).

DNA binding of 1 '+C-ethyl carbate lablled in either the ethyl or the carbanyl group and of 1 '+C-rnthyl cabate lablled in the rrthyl group has be investigated in rruse liver and kidney. Ony ethyl cabate lablled in the ethyl group binds ta liver DNA to a signficant extent (Lawson & Pound, 1973). The incorpration of 3H-rnthyl cabate into liver-cell RN has ben examed in mice (William et al., 1971).

Methy 1 carbate did not induce an increase in the Humber of strepto- mycin-independent mutations in Escherichia coli (Hemrly & Deerec, 1955), and no reverse mutations were recorded in Baci L lus subti lis (De Giovani- Donnelly et al., 1967); rrtallic activation system were not used in these tests. An i. p. dose of 200 or 1000 rr!kg caused 00 increase of domiant lethals in mice (Epstein et al., 1972). ln the presence of Aroclor- inuc rat li ver microsas, !X reverse mutations oced in Sa lmone L la typhimiwn strains TAlOO, TA98, TA535 or TA537 (Mcnn et al., 1975) .

155 (b) Ma

No data were available to the Working Group. 3 . 3 Case reports and epiderological studies

No data were available to the Working Group.

4. Cornnts on Data Reported and Evaluation 4 . 1 Animl data Methyl carbate has ben tested for skin and lung tumur induction in mice by subtaeous and intraperi toneal admistration and by skin application. Although no significant cacinogenc effect was observed, no evaluation of carcinogenicity can be rrde due ta the short duration of these eximnts. It rnt be pointed out that in paallel exprimnts the related chemcal, ethyl cabarte, was cacinogenic (IAC, 1974). 4 . 2 Hur data

No case reports or epidemological studies vvre available to the Working Group.

156 5. References

Baina, M.D. (1975) Determnation of alkl carbates in air. Gig. i Sanit., 7, 76-77

Boyland, E. & Nery, R. (1965) The rrtalism of urethane and related compunds. Biochem. J., 94, 198-208

Boyland, E. & Papadopoulos, D. (1952) The rrtallisr of rrthyl carbate. Biocher. J., 52, 267-269

De Giovani-Donnelly, R., Kolbye, S.M. & DiPaolo, J.A. (1967) Effect of carbamtes on Baciiius subtilis. Mutation Res., 4, 543-551

Epstein, S. S., Arnold, E., Andrea, J., Bass, iv. & Bishoo, Y. (1972) Detection of chemcal rntagens by the domiant lethal assay in the rnuse. Toxicol. aDDl.J-J- Phacol., 23,_ 288-325 Fishbin, L. & Zielinski, W.L., Jr (1967) Chromatography of carbamtes. Chornt. Rev., 9, 37-101

Hata, H. (1970) Maufacture of cabartes. Japan Patent 70 23,536, Augut 7, to Dainippon Ink and Chcals, Inc. and to Dainippon Ink Research Insti tute Hemrly, J. & Derec, M. (1955) Tests of chercals for rntagenicity. Cancer Res., 15, 69-75

Hill, J. (1967) Resin consumtion in DP. Textile Industries, 131, 123-126 lAC (1974) IA Monographs on the Evaluation of Cacinogenic Risk of Chercals to Ma, 2, SOID Anti -thyroid and Related Substances, Nitro- furans and Industrial Chemcals, Lyon, po. 111-140

Karawya, M.S., Wassel, G.M., Baghdadi, H.H. & Ah, Z.F. (1972) Isolation of rnthyl carbamte from four Egtian 8also la species. Phytochemstr, 11, 441-442

Knappe, E. & RohdßVald, 1. (1966) Dfuschichtchrortographie von substi- tuierten Harstoffen und einfachen Urethanen. Z. analyt. Cher., 217, 110- 113

Iadas, A.S. & Ma, T.S. (1973) Organic functional group analysis via gas chromatography. III. Determnation of carbates by reaction with alkali. Mikrochir. acta (Wien), 853-862 Lasen, C.D. (1947) Evaluation of the carcinogenicity of a series of esters of carbac acid. J. nat. Cancer Inst., 8, 99-101

157 Lawson, T.A. & Pound, A.W. (1973) Th interaction of carbon-14-lablled

alky 1 carbates, lablled in the alk 1 and cabon y 1 fDsi tions 1 wi th DNA in vivo. Chem.-biol. Interact., 6, 99-105

McCan, J., Choi, E., Yarsaki, E. & Ars, B.N. (1975) Detection of carcinogens as mutagens in the Sa lmone L lalmicrosorn test: assay of 300 chercals. Proc. nat. Acad. Sci. (Wash.), 72, 5135-5139

Nery, R. (1969) Gas-chromtographic deterrnation of acetyl and tri1thyl- silyl derivatives of alkyl cabartes and their N-hydroxy derivatives. Analyst, 94, 130-135

Pound, A.W. (1967) The initiation of skin twrurs in mice by hoirloges and N-substituted derivatives of ethyl cabate. Austr. J. exp. BioL. me. Sci., 45, 507-516

Pound, A.W. & Lawson, T .A. (1976) Cacinogenesis by cabac acid esters and their binding to DNA. Cancer Res., 36, 1101-1107

Prager, B. & Jacobson, P., eds (1921) Beilsteins Handbuch der organschen Cheme, 4th ed., Vol. 3, Syst. No. 201, p. 21 Roe, F.J .C. & Salam, M.H. (1955) Further studies on incornlete cacinogenesis: triethy lene rrlarne (T. E. M.), l, 2-benzanthacene and ß-propiolactone as ini tiators of skin twrur formtion in the iruse. Brit. J. Cancer, 9, 177-203

Shirin, M.B., Wieder, R., McDonough, M., Fishbin, L. & Swrn, D. (1969) Lung twrr response in strain A rnce as a quanti tati ve bioassay of carcinogenic acti vi ty of son cabates and aziridines. Cacer Res., 29, 2184-2190 Slater, J .D. & Culbreth, W.J. (1971) Cabac ester process and ferilizer values therein. US Patent 3,544, 730, Januar 12, to Kaser Alurm.:r and Chercal Co.

Sri valova, T. 1. (1973) Toxic and spif ic action of al 1 cartes and their binary mixture. Toksikol. Nov. Promo Kh. Veshchestv., 13, 86-91

US . International Trade Commssion (1975) Synthetic Organic Chcals, us Production and Sales, 1973, ITC Pulication 728, Washington OC, US Governt Printing Office, p. 217 US Tariff Commssion (1960) Sythetic Organc Chcals, US Prouction and Sales, 1959, ReDOrt No. 206, Second Series, Washington OC, us Goernnt Printing ()fice: p. 160

158 Vishnyakova, T.P., Paushkin, Y.M., Faltynek, T.A., Golubva, I.A., Liakuivich, A.G. & Michurov, Y.I. (1969) Synthesis of all carbamates, selective solvents for hydrocaroons. Neftepererab. Neftekir., l, 27-29

Vishnyakova, T.P., Paushkin, Y.M., Faltynek, T.A., C-olubva, LA., Fedorov, V.V. & Shuleiko, G.F. (1971) Synthesis of alkyl carbates in the presp.nce of an alurnosilicate catalyst. Kh. Tekoi. TapI. Masel., 16, 10-14

Weast, R.C., ed. (1975) CRC Hadbk of Chstr and Physics, 56th ed., Cleveland, Ohio, Chemcal Rubber Co., C-23l William, K., Kunz, W., Petersen, K. & Schnieders, B. (1971) Chges in rnuse liver RN induced by ethyl cabate (urethane) and rrthyl carbamte. Z. Krebsforsch., 76, 69-82 Yaguv, A.S. & Suvalova, T.I. (1973) Cærrative evaluation of the blasto- moenic action of a bina miture of alk lcarbates and i ts co:r- nents. Gig. Tr. Prof. Zabl., ~, 19-22

159 ME SELC

1. Chcal and Physical Data 1. 1 Synonyr and trade nas

Chem. Abstr. Reg. Serial No.: 144-34-3

Chem. Abstr ~ Nar: Tetraks (dimthylcabaithioato-8, SI) selenium

Selenium dimthy ldi thiocaba te 1. 2 Chemcal formula and molecular weight

~ 1\ (CH3CH3/N-C-S S) 4Se

C12H24 N 4 S gSe M:Ü. wt: 559.8 1. 3 Chemcal and physical properties of the pure substance

No data were available to the Working Group. 1.4 Techncal products and iruri ties

M.thy 1 selenac available camrciall y ll the us has the follcwing specifications: yellcw pcer¡ density, 1. 58 :! 0.03 ¡ rrlting range, o 140-172 C¡ particle size, 99.9% passes though a 100-rnsh scree¡ selenium content, l3-l5%¡ IIisture, 1% ma. ¡ ash, 0.75% rn. (Ann., 1974). Methyl selenac is also available for ru processing in a dispersion containng 30% ethylene-propylene rur binder (Ann., 1975).

2. Production, Use, Occurrence and Anal ysis

For imrtant background informtion on ths section, see preale, p. 15.

161 2. 1 Production an use

The usual rnthod for the preparation of water-insoluble dialkl- di thocarbate rntal sal ts is precipitation of the rrtal salt from an aqueous prepaation of the sodium dialkldithiocarbate (Shaver, 1968). Comncial production of rrthyl selenac was first reported in the us in 1946 (US Tariff Commssion, 1948); in 1974, only one maufacturer reported production (US International Trade Commssion, 1975). It is not produced comncially in Europe.

Methyl selenac is used in the ruber-processing industry as an accelerator to produce desired physical properties in vulcanized rur in a shorter curing tim and at lo.er sulphur levels than wi th conventional accelerators. It is used in counding heat-resistant natural and synthetic rubers (Supp & Gibbs, 1974). Accordin; ta the US Occuationa Safety an Heal th admnistration heth stads for air contanas, an emloye' s exsur ta selenium corrun shuld rot exceed 0.2 rr/m3 (as Se) in the v.rkplace air during any eight-hour workshift for a forty-hour v.rk week (US Coe of Federal Regulations, 1975). ln the USSR, the maimum allo.able concentration of selenium cOITunds in the work environrent is 0.1 rr/m3 (Winell, 1975).

2 . 2 Occurrence Methyl selenc iS not knaw to occur as a natural product. 2. 3 Anal ysis Methods for the gas chromtogaphic analysis of selenium have æen reviewed (Young & Chistian, 1973). Gas chrantography coupled with a microwve-emssion spetrauetric detection system has ben used for deterrnation of trace aiunts of selenium in environmtal sanles (Talm & Andren, 1974). M.thyl selenac has been deterrned in ruber additives by bath atomic absorption spectrorrtr and wet analytical deterrnation of selenium (Supp & Gibbs, 1974).

M.thods for the chromtographic anal ysis of carbaates, includng thocarbates, have ben reviewed (Fishbin & Zielinski, 1967). A thin- layer chromtographic-spectrophotofluorimtric rrthod (van Hoof & Heyndrickx,

162 1973) is suitale for the anlysis of a variety of rrtal dithocabates, al though i t was not applied to rrthy 1 selenac i tself .

3. Biological Data Relevant ta the Evluation of Cacinogenic Risk to Ma 1

3. 1 Carcinogenici ty and related studies in animls

(a) Oral admistration

Mouse: Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F rnce and 1 18 male and 18 ferle (C57BL/6xA)F mice received corcial nethyl 1 selenac (rn.p. l40-l720C) according to the followng schedule: 10 rr!kg bN in gelatine at 7 days of age by stomach tub and the sar aiunt (not adjusted for increasing bcy weight) daily up to 4 weeks of age¡ subse- quently, the mice were given 34 rr nethyl selenac per kg of diet. The dose was the rn talerated dose for infant and young rnce but Ilt necessaril y so for adul ts. The exrirnt was terrnated when the mice were abut 78 weeks of age, at which ti 13, 17, 18 and 17 rnce in the four groups, respetively, were still alive. Tuur incidences were cornared with those observed aIng 79-90 necropsied rnce of each sex and strain, which either had ben untreated or had received gelatine only: th incidences were not significantl y greater (P:?O. 05) for any turur typ in any sex-strain suboup or in th cornined sexes of ei ther strain. Tuurs were found in 4/17 males and 0/17 ferles of the first strai and in 1/18 males and 2/17 ferles of the second strain (5 reticulLnucell sarcos, 1 hepaton and 1 renl adenorr) (Innes et aL., 1969 ¡ NI'S, 1968). (b) Subtaeous admistration

MJuse: Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F mice and 1 18 male and 18 ferle (C57BL/6xA)F mice W2re given single s.c. injections 1 of 464 rr!kg bN corrcial rnthyl selenac (rn.p. l40-l720C) in 0.5% gelatine on the 28th day of life and were observed until they were alut 78 weeks of

lSee also the IInograph on selenium and selenium cornunds (IA, 1975). 163 age, at which tii 13, 15, 18 and 17 rnce in the four groups, respcti vel y, were still alive. Tuur incidences were coed with those in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. Incidences were not increased (P:?0.05) for any tUIur ty in any sex-strain subroup or in the coined sexes of ei ther strain (NlIS, 1968) (The Working Group noted that a negative result obtained with a single s.c. injection may not be an adeqate basis for discounting carcinogenici ty ) . 3.2 Oter relevant biological data

No data were available to the Working Group. 3. 3 Case reports and epidemological studies

No data were available to the Working Group.

4. Corrnts on Data Reported and Evluation 4 . 1 Aninl data

Methyl selenc has ben tested by oral adistration and by single s.c. injection in tv. strais of rnce. Although no carcinogenic effect was observed in these tests, the available data are inufficient to allow an evaluation of the cacinogenicity of this cound. 4.2 Hur data

No case reports or epidemological studies were available to the Working Group.

164 5. References

Anon. (1974) Methyl selenc(S 1 Ne- York, R.T. Vanderbilt Co. Anon. (1975) M:terials and Comunding Ingredients for Ruber, Na York, Bill Commications, pp. 47-48 Fishbin, L. & Zielinski, W.L., Jr (1967) Chamtoraphy of cabates. Chrmat. Rev., 2., 37-101 van Hoof, F. & Heyndrickx, A. (1973) Thin layer chortogaphic-spectro- photophuorirtric rrthods for the deterration of ditho- and thiolcarbates after hydrol ysis and coupling wi th NBD-Cl. Ghent. Ri jks- univ. Fac. Ladbl. l1., 38, 911-916 IAC (1975) lAC rrnographs on the Evluation of Carcinogenic Risk of Checals to Ma, 9, So Aziridines, N-, S- and O-Mustards and Selenium, Lyon, pp~ 250-251

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrcelli, L., Fishbin, L., Har, E.R., Pallotta, A.J., Bates, R.R., Fal, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for turrigenici ty in mice: a prelirar note. J. nat. Cancer Inst., 42, 1101-1114

NTIS (National Techncal Inforntion Service) (1968) Evluation of Cacinogenic, Teratogenic and Mutagenic Acti vi ties of Selected Pesticides and Industrial Chercals, Vol. l, Carcinogenic Study, Washington DC, US Departt of Coce

Shaver, F .W. (1968) Ruber chercals. ln: Kik, R.E. & Otr, D.F., ed, Encyclopeia of Chemcal Technolog, 2nd ed., VoL. 17, NEW York, John Wiley & Sons, pp. 513-514

Supp, G.R. & Gibbs, 1. (1974) The deterration of selenium and telluriur in organic accelerators used in the vucanzation process for natural and synthetic rubers by atomc absorption sl:ctrortr. Atorc Absorption Newslett., 13, 71-73

Talm, Y. & Andren, A. W. (1974) Determtion of selenium in envirorintal sarles using gas chrortoaphy wi th a rncro.ave emssion spctro- rntric detection syste. Anlyt. Chem., 46, 2122-2126

US Coe of Federal Regations (1975) Ai Contaants, Title 29, pa. 1910.1000, Washington DC, US Governt Printing Office, pp. 59, 61

US International Trade Commssion (1975) Synthetic Organic Chcals, us Production and Sales of Rur-Processing Cherca1s, 1974 Prelirar, Washington DC, US Governt Printing Office, p. 8

165 US Tariff Corrssion (1948) Sythetic Organc dEcals, US Production and Sales, 1946, Report No. 159, Second Series, Washingtn De, US Goernt Printing Office, p. 123, 155

Winell, M.A. (1975) An interntional coison of hygienic standads for chercals in the \\rk environmt. Ario, 4, 34- 36

Young, J .W. & Chistian, G.D. (1973) Gas-chrortographic deterrnation of selenium. Analyt. chi. acta, 65, 127-138

166 MJNUN

1. Chemcal and Physical Data 1 . 1 Synonyms and trade nas

Chem. Abstr. Reg. Serial No.: 150-68-5

Chem. Abstr. Nam: N' - ( 4-Choropheny 1) - N, N-dimthy lurea 1 -para-Chloropheny 1-3, 3-dimthy lurea; 3- (4-chloropheny 1) - 1,1- dimthylurea; 3 '- (4' -chlorophenyl)-l, l-dithylurea; 3-para- chlorophenyl-l,l-dimthylurea; N- (4-chlorophenyl) -N' ~ N '-dimthylurea; N-para-chloropheny 1 - N ' ~ N ' -dithy lurea; CM; l, 1 -dithy 1-3- (para- chloropheny 1) urea; N ~ N-dimthy 1 - N' - ( 4-chloropheny 1) urea Karm !-nuron Herbicide; Ka W. !-nuron Herbicide; !-nurex; !-nurox¡ !-nuron; Monuuron; Telva; Telvar M::muron Weeller; Tel var W. Monuron Weeiller 1. 2 Chemcal fonmla and ITlecular ~ight oIl CHi/ ~Hï-C CH,-N ""

Ci C9Hii C1N20 MoL. wt: 198.6

1.3 Chemcal and physical propeties of the subtace

From Weast (1975), uness otherwise speified

(a) Description: Platelets

(b) Mel ting-point: 170. 5- 171. SoC (c) Spectroscopy data: rrÀ = 247 nm (Stecher, 1968); for infra-red and mass spctral data, see Grasselli (1973)

167 (d) Solubility: Very slightly soluble in water, in hydrocarban solvents and in No. 3 diesel oil (Stecher, 1968); irate1y soluble in rnthanol, ethanol and acetone

(e) Volatility: Vapour pressure is 5 x 10-7 rr at 250C and 178 x 10-5 mm at 1000C (Stecher, 1968).

(f) Stability: Negligible hydrolysis at roo temratures in neutral solutions (Association of Amrican Pesticide Control Officials, Inc., 1962)

1.4 Technical products and imurities

!-nuron is available in the US as a technical grade product, as a wettale paer containing alut 80% of the chemcal and as granular formlations containng 2.4-8%. Granular formlations containing bath rrnuron and trichloroacetic acid are also available, wi th several concentrations of each active ingredient (US Environrtal Protection Agency, 1975) .

2. Production, Use, Occurrence and Anal ysis

For imrtat background informtion on ths section, see prearle, p. 15. A review on nDnuron has be pi.1ished (US Environrtal Protecton Agency, 1975). 2 . 1 Production and use

Eight irthods for the synthesis of ITnuron have teen reported (US Environrtal Protection Agency, 1975); th rrthod use comrrcially is believed to be the reaction of para-chloroailine wi th phosgene and subseqentl y wi th dimthy lame (P limr, 1970). Monurn we firstproduced commrcially in the US in 1951 (US Tariff Corssion, 1952). US production in 1973 was estirted to be 230-400 thousand kg; someat larger qutities are telieved to have been produced in ear lier years when wider use was perr tted in the US and a lesser numr of competitive products existed. US imrts in 1973 were 65 thousand kg, and exrts were alut 45 thousand kg (US Environrtal Protection Agency, 1975).

168 The onl Y known use of rrnuron is as a broad-sptr herbicide for the control of rny grasses and herbaceus w=eds on non-cropland areas, such as rights-of-way, industrial si tes and draiage di tch bans. ln the past, m::muron was registered in the US for selective control of v.s ln several crops, and rrnuron residues of 1-7 m:/kg w=re tolerated on a variety of fruts and vegetales. As of July 1973, howver, TInuron is no longer registered for use on any agricutural crop (US Enviroruntal Protection Agency, 1975). 2. 2 Occuence !-nuron is not knaw to occu as a natural product.

When it was applied at rates fo:nrly used on crops, phytotoxc concentrations disappared from the sail wi thin one year. When applied at non-selective rates for total vegetation control, e.g., on rights-of-way, it retains its phytotoxic activity for several seasons. Lager applications of rrnuron (20 to 200 kg/hectae) have reqred up to 3 years to dissipate (US Environmtal Protection Agency, 1975).

ln one investigation of the persistence of TInuron in river water, acetone solutions of rrnuron w=re injected into water sarles whch were expsed to natural and artificial light at room temrature. By the end of 1 week, 40% of the rrnuron remned; at 2 wes, 30%; at 4 wees, 20%; and at 8 weeks, 0% (US Enviroruntal Protection Agency, 1975). 2. 3 Anal ysis Methods for the deterration of TInuron have be reviewed (Lcen et al., 1964; Zweig & She:r, 1972), and several other reviews have dealt with analytical rnthods for pesticides strcturally related to this naterial (Fishbin, 1975; Shern, 1973). A review has also be ffde of rnthods of mass spetrortry for a variety of pesticides, including rrnuron (Safe & Hutzinger, 1973). Gas chortogaphy has be used to deterre rrnuron and i ts hydro- losis products (Buser & Grolim, 1974; Guten & Lisk, 1964; I.ence & laver, 1974; Lichtenrg, 1975). Gee (1973) describd a th-layer chrortoaphic screening test for phenylurea herbicides tht inhi t certin enzyc acti vi ties . 169 A rapid biolumescence rrthod capale of deterrning 10l concentrations of photosynthesis-inibiting herbicides, such as rrnuron, in water and soil bas been describ by Tcha et aL. (1975).

3. Biological Data Relevant ta the Evluation of Carcinogenic Rik to Ma

3.1 Carcinogenicity and related studies in anls

(a) Oral admistration

!-use: Groups of 18 male and 18 fere (C57BL/6xC3H/An)F rnce and 1 18 male and 18 femle (C57BL/6xA)F mice received comærcial rrnuron 1 (95% pure) according to the followng schedule: 215 mg!kg ÌM in 0.5% gelatine at 7 days of age by stomach tub and the sa arunt (not adjusted for increasing boy w=ight) daily up to 4 w=eks of age; subse- quentl y, the mice were gi ven 517 mg per kg of met. The dose was the maim tolerated dose for infant and young rnce but not necessaril y so for adults. The exrimt was terrated when the mice were abut 78 weeks of age, at which tim 15, 18, 16 and 17 mice in th four groups, respeti vel y, were still ali ve. 'lur incidences were comped wi th those in 79-90 necropsied rnce of each sex and strain, which either had ben untreated or had received gelatine only. Tturs occured in 7/15 necropsied males (2 reticulumcell sarcors, 2 lung adenomas, 3 hepatonis) and in 0/18 necropsied femles of the first strain, and in 6/16 necropsied males (6 lung adenomas) and in 3/17 necropsied feres (l reticulumcell sarcoma and 2 lung adenorrs) of the second strain. Ttur incidences were significantly different only for lung adenors in rrles of the second strain (6/16 oorned with 9/90) (p~O. 01) (Innes et al., 1969; NTIS, 1968).

Groups of 25 random-bred and 25 C57BL rnce (sex unpecified) w=re given 6 mg/animl ITnuron in milk by storch tub wely for 13 rrnth, at which tim the 23 and 25 surivors ~re killed. A total of 13 tlTurs occured in 13 randanbred mice, cornrising 1 storrch adenocarcinoma, 4 hepatomas, 4 hepatocellular carcinorns, 2 lung tururs and 2 rnlignt kidney tUlurS. Of the 25 C57BL rnce, 7 had tlTurs, cornrising 1 lyrphoma of the intestine, 2 hepatans, 2 liver-cell carcinorns, 1 lung hninur and 1 rnlignant kidney

170 ti.ur. No ti.urs occured in an eql numr of untreated random-bred controls; one hepatoma occurred aTng C57BL controls; hCMever, surival rates aTng controls were not reported (Rubnchik et aZ., 1970).

Rat: Four groups of 30 male and 30 fene 4-wee old alino rats (Rochester, ex-Wista) were fed diets containing 0 (control), 0.0025, 0.025 or 0.25% rnnuron for up to 2 years, at 'Wich tir 10-30% were still alive. Twenty-four tururs (mainl y 1 ymphorrs and rr fibroadenors) occured in the groups killed at 2 years, and abut 30 rats died with tururs before 2 yeas. The total turur incidence was reported to te wi thn the range of that in control rats of that colony (Hcxge et aZ., 1958) (Inccrlete reporting of data rnes evaluation of this exrimt difficult).

A group of 50 randombred male rats was given 450 ff/kg m::muron in the foo dail y for 18 nonths and observed for a furer 9 IInths, at which tim 32 treated and 30 control rats were still ali ve. TLurs occurred in 14 rats and included 2 stomach tururs, 1 malignant turur of the intestine, 1 hepatom, 2 liver-cell carcinorrs, 2 alveolar cacinomas, 4 smll-cell carcinors of the lung and 2 sernomas. The first turur appeared after 18 weeks. No tururs were reported to have occured in 50 control rats (Runchi et al., 1970) (The absence of tururs in controls was considered to be unusual).

(b) Subtaeous admistration

Mouse: Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F mice and 1 18 rrle and 18 ferle (C57BL/6xA)F mice were given single s.c. injections 1 of 100 mg/kg bv rrnuron (95% pure) in 0.5% gelatine on the 28th day of life and were obsered until they were alut 78 weeks of age, at whch tim 15, 18, 18 and 16 mice in the four groups, respectivelyi were still alive. Tuur incidences were compred with tliose in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. Incidences were not increased (P:;O. 05) for any ti.ur ty in any sex-strain suboup or in the cornined sexes of either strain (NTIS, 1968) (The Working Group noted that a negative result obtained with a single s.c. injection may not be an adeqte basis for discounting carcinogenicity).

171 3.2 Oter relevant biological data (a) Exrimntal system

The oral LD in rats ranged frc: 1480 ta 3700 m~/kg b. (Ben-Dye 50 et aL., 1970). No toxic effects ~re observed in rats follcwing oral admistration of 25 mg/kg bw/day for 2 years; doses 10 lis higher produced slight toxic effects (Hooge et al., 1958).

ln rats given 875 ff/kg hw orally, peak bloo concentrations occurred 2 hours after dosing; thereafter, the coIlund was distributed evenl y thoughout the lxy. !-nuron-related material was excreted in the urine and secreted into the milk of lactating anls. After admistration of 175 ff/kg b./day for 60 days or of 0.1-20.0 ID/kg b./day for 6 nonth, tissue retention of irnuron-related substaces occured in the lungs ). hea ). li ver, brain and kidneys ). milk, oone-macw and thyroid gland (Fridm, 1968).

ln nils, rrnuron 1S rrtallized (i) by oxidative N-derthylation, (ii) by hydroxylation of the arantic nucleus and (iii) by fission of the urea residue to give chloroailine derivatives (Ernst, 1969; Ernst & Böhm, 1965). The principal urinar rrtallites of rrnuron (1) (Scher 1) in rats are N-(4-chlorophenyl)-N'-rrthylurea (2), N-(4-chlorophenyl)urea (3) (14.5% of the dose), N-(2-hydroxy-4-chlorophenyl)-N'~N'-dthylurea (4), N- (2-hydroxy-4-chlorophenyl) -N' -rrthylurea (5) (1.5%), N- (2-hydroxy- 4-chlorophenyl)urea (6) (6.5%), 2-acetano-5-chorophenol (7) and N- (3- hydroxy-4-chlorophenyi)urea (8) (2.2%).

The yields of the various rrtalites indicate that hydroxylation favours the 2-¡:sition rather th the 3-¡:sition. Ph2nolic rrtalites were excreted in the urine as conjugates. 4-Choro-2-hydroxyaniline was excreted as the N-acetyl cornund (7) (Ernst, 1969; Erst & Böhm, 1965). (b) M:

No data were available to the Working Group. 3. 3 Case re¡:rts and epidemological studies

No data were available to the Working Group.

172 SC 1

~N(CH'), qH' o OH OH ~O:' 0 · (~F~H'0 · 0 · 0 Ci Ci Ci Ci CI (I 6.5% (! NHnNH2 ø 1.5% l ~OH Ci CI 2.2% 1 NHCN~H 3) NHnNHCH 3 qH' · 0 · c9 ~Ci ' Ci Ci

CD ~ æ 14.5%

173 4. Comnts on Data Reported and Evaluation 4 .1 Animl data

Monuron has ben tested in mice and rats by oral adistration and in mice by single subutaeous injection. ln one study by oral admistration in mice, an increased incidence of lung tUlurs was observed in males of one of tv strains. ln a furer study in mice, an increased incidence of li ver tururs was observed, but suri val rates in controls were not reported. ln one study by oral admistration in male rats, tururs were observed at various si tes; none w:re observed in concurrent controls. The available data suggest that rrnuron is cacinogenic. 4.2 Hum data

No case reports or epidemological studies were available to the Working Group.

174 5. References

Association of Arerican Pesticide Control Officials, Inc. (1962) Pesticide Chemcals Official Compdium, Box RH, University P.O., College Park, Marylan, p. 211

Ben-Dyke, R., Sanderson, D.M. & lbakes, D.N. (1970) Acute toxicity data for pesticides (1970). wid Rev. Pest. Control, 9, 119-127

Buser, H. & Grolirund, K. (1974) Direct deterrnation of Nl-phenyl urea deri vati ves in herbicide tehnical procucts and formlations, using gas-liquid chrartoaphy. J. Ass. off. anlyt. Ch., 57, 1294-1299

Erst, W. (1969) Metallisr of substituted dinitrophenols and ureas in rnls and rnthocs for the isolation and identification of metali tes. J. Suid-Afrik. chem. Inst., 22, S79-S88

Erst, W. & Böhm, c. (1965) ntr den Stoffwchsel von Harstoff-He..biciden in der Ratte. 1. !-nuron un Aresin. Fd Cosrrt. TOxicoL., 3, 789-796

Fishbin, L. (1975) Chorntography of Environmtal Hazards, VoL. 3, Pesticides, Amterda, Elsevier, pp. 690-732

Fridr, E.B. (1968) Distribution and accuation of rrnuron in anls, and rnthocs of its excretion. Zdravookh. Tukm., 12, 25-27 Geike, F. (1973) Thn-layer chrcmtogaphic screening test for the detection of initing properties of phenylurea herbicides on certain enzyms. J. Chrornt., 87, 199-210 Grasselli, J .G., ed. (1973) Atlas of Spectral Data and Physical Constats for Organic Cornunds, Clevelan, Ohio, Chemcal Ruber Co., p. B-983 Guten, W.H. & Lisk, D.J. (1964) Electron affinity residue deterration of CIPC, rrnuron, diuron, and linuron by direct hydrolysis and bromina- tion. J. agric. Fd Chem., 12, 46-48 Hocge, H.C., Maynd, E.A., Das, W.L. & Coye, R.D. (1958) Chronic toxicity of 3- (p-chlorophenyl) -l, l-dithylurea (rrnuron). Arch. industr. Hlth, 17, 45-47

Innes, J .R.M., Ulland, B.M., Valerio, M.G., Petrucelli, L., Fishbin, L., Hat, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chercals for tUIrigenici ty in mice: a prelirar note. J. nat. Cancer Inst., 42, 1101-1114 Lawrence, J.F. & Laver, G. W. (1974) Anlysis of cabate and urea herbicides in foo, using fluorogenic labling. J. Ass. off. anlyt. Chem., 57, 1022- 1025

175 Lichtenrg, J.J. (1975) Method for the deterrtion of spific organic pollutats in water an waste water. Inst. Electrical Electronics Enginees Trans. Nuclear Sci., NS-22, 874-891

IDen, W.K., Bleidner, W.E., Kirkland, J.J. & Pease, H.L. (1964) Monuron, Diuron, and Neburon. ln: Zv.ig, G., ed., Anlytical M2thods for Pesticides, Plant GrON Relators and Fco Addi ti ves, Vol. 4, Herbicides, New York, Acadec Press, pp. 157-170

NTIS (National Techncal Inforntion Service) (1968) Evluation of Cacino- genic, Teratoenic and Mutagenic Acti vi ties of Selected Pesticides and rndustrial Chemcals, Vol. l, Cacinogenic Study, Washington IX, US Deparnt of Comrce

Plirr, J .R. (1970) Wee killers. ln: Kirk, R.E. & Otl, D.F., eds, Encyclopeia of Chercal Technolog, 2nd ed., VoL. 22, Nev York, John Wiley & Sons, pp. 188-191

Ruchi, B.L., Bots, N.E. & Gorbaj, G.P. (1970) On cacinogenic effect of herbicide irnuron. Vop. Onol., 16, 51-53 Safe, S. & Hutzinger, O. (1973) Mas Spetrortry of Pesticides and Pollutats, Cleveland, Ohio, Chemcal Ruber Co., pp. 147-151 Shern, J. (1973) Chortoaphic analysis of pesticide residues. CR Crit. Rev. analyt. Chem., 3, 299-354 Stecher, P. G., ed. (1968) The Meck Index, 8th ed., Raway, NJ, Merck & Co., pp. 700-701

Tcha, Y.T., Roseb, J.E. & Funell, G.R. (1975) A riw rapid spcific bioassay method for photosythesis inibi ting herbicides. Soil Biol. Biochem., 7, 39-44 us Environrental Protection Agency (1975) Initial Scientific and Mii- econorc Review of Monuron. Substitute Chemcal Proam, EPA-540jl-75-028, Washigton DC, US Depatrnt of Corce, pp. 2, 5, 21, 92-93, 98-101 US Tariff Commssion (1952) Synthetic Organic Chcals, US Prouction and Sales, 1951, Report No. 175, Second Seies, Washington IX, US Governnt Printing Office, p. 135

Weast, R.C., ed. (1975) CRC Handbk of Chstr and Physics, 56th ed., Cleveland, Ohio, Chemcal Rubber Co., p. C53l

Zweig, G. & Sherr, J. (1972) Monuron, Diuron, and Neburon. ln: Zweig, G., ed., Analytical M2thods for Pesticides, Plant Grow Regators and Foo Addi ti ves, VoL. 6, Gas chromtographic anal ysis, New York, Academc Press, pp. 664-666

176 PHECAIDE

1. Checal and Physical Data 1. 1 Synonym and trade nas

Chem. Abstr. Reg. Serial No.: 39538-93-7 Chem. Abstr. Nam: 2-Phenylhydrazinecarboxade

1 -crbayl -2-phenylhydrazine; l-carbal -2-phenylhydrazine; 2-pheny ldiazenecarboxade; 2-pheny lhydrazide , cabarc acid ¡ 1 -pheny lhydrazine carboxade ¡ pheny lsecarbazide; i -pheny lsem - carbazide

CPH; Cryogenine ¡ Krogenin 1.2 Chemcal forma and rrlecular weight

,,0 ~NH-NH-C~ NH2

C7H9N30 MoL. wt: 151. 2 1 . 3 Chemcal and physical properties of the substace

From Stecher (1968), unless otherwse spified

(a) Description: Leaflets from water

(b) Melting-point: l720C (c) Spectroscopy data: Àrn = 282 and 233 nr in rnthanol (Grasselli, 1973) ¡ for infra-red spetral data, see Grasselli (1973)

(d) Solubility: Very soluble in hot water, ethanol, rrthanol and acetone¡ slightly soluble in cold water, ethyl ether, benzene and ligroin

177 1.4 Techncal products and iruri ties

No data were available to the Working Group.

2. Production, Use, Ocurrence and Anlysis

For imrtant background inforntion on ths section, se preale, p. 15. 2 . 1 Production and use

Preparation of phenicarbazide was first reported in 1893 by ivildm, who synthesized it by reacting an aqueous solution of phenylhydrazine acetate with potassium cyanate (Stecher, 1968). It ca also be prepaed by adding urea to an aqueous solution of phenylhydrazine

(Andraca, 1941).

No indication was found that phenicarbazide is produced in comærcial quti ties in the US, al though i t is produced by one maufacturer for research purses. It was estimted that 5 thousand kg were produced in Italy in 1975.

Phenicarbazide has been tested c1inically as an antipyretic and as a neuroleptic agent (Nucifora & Maone, 1971) and has ben describd in patents for use as an aldehyde polyrrization catalyst and stailizer for viny 1 canunds; hOVJver, no evidence was found that i t is used cornrciall y for these purses. 2 . 2 Occurrence Phenicabazide is not know ta occu as a natural product.

2.3 Analysis

No anlytical rrthods suitable for th deterration of phenicarbazide in enviroDIntal sarles VJre available to the Working Group.

178 3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma 1

3.1 Carcinogenicity and related studies in anls Oral admistration

Mouse: Corrrcial phenicabazide (rn.p. l74-l750C) was adristered for lifespa to 50 7-week old ferle and 50 7-~ek old mae Swss mice as a 0.25% solution in the drining-water. Th daily intake was 20.4 mgl femle and 25 mg/nile. Lifespa of treated animls was shortened, pari- cular 1 y for males: 11 femles and 5 males li ved to 80 w=eks of age versus 71/100 and 65/100 controls. ln treated anirls, 205 lung tumurs were found in 39/50 females (30 with 126 adenomas; 9 with 18 adenoc- cinonis and 61 adenomas) and 152 in 33/49 males (28 with 108 adenoms; 5 wi th 8 adenocarcino:r and 36 adenomas), (X)I(ipared wi th 31 in 21/99 untreated femles (17 with 23 adenonis; 3 with 5 adenocarcinonis; 1 with 1 adenom and 2 adenocarcinoms) an 35 in 23/99 untreated males (10 with 12 adenomas; 8 with 11 adenocarcinomas; 5 with 6 adenomas and 6 adenocarcinoms). Average ages at death in mice wi th lung tUIurs were 73 and 64 weeks in treated ferles and niles, respectively, and 95 and 92 weeks in control femles and males" respectvely. Angioms or angiosarcas were found in the livers of 12/99 treated mice and of 9/198 controls (P~0.02). Tuurs occured at other sites in low incidences (Toth & Shimzu, 1974). 3. 2 Oter relevant biological data

1\ data were available to the WJrking Group. 3. 3 Case reports and epidemological studies

No data were available to the Working Group.

lPhenicabazide is a hydrazine derivative. For a discussion of hydrazine and related substaces, see IAC (1974).

179 4. Corrts on Data RePOrted- and Evluation 1 4 . 1 Anirl data Phenicarbazide is cacinogenic in mice when adrnistered orall y, the only speies and route investigated. It produced lung tUIurS and angiomas and/or angiosarcos in the li ver. 4 . 2 Hur da ta

No case reports or epidemological studies were available to the Working Group.

lSee also the section, 'Anl data in relation to the evaluation of risk to ma' in the introduction to this volur, p. 13.

180 5. References

Andraca, A. (1941) Study ar sythesis of phenylsecarbazide. An. qulI. fann., 15- 26

Grasselli, J .G., ed. (1973) Atlas of Spetral Data and Physica1 Constats for Organic Coruns, Cleveland, Oho, Clcal Ruber Co., p. B-89l lAC (1974) IA M:mographs on the Evluation of Cacinogenic Risk of Chemcas ta Ma, i, Sar Arortic Amnes, Hydrazine and Related Substaces, N-Nitroso Ccrunds and Miscellaneous A1lating Agents, Lyon, pp. 127-136 Nucifora, T.L. & M:lone, M.H. (1971) Canative psychophacologic investigation of cryogenine, certin nonsteroid antiinflartory corrunds, lupine alaloids, and cyroheptadie. Arch. int. Pha- codyn. Ther., 191, 345-356 Stecher, P.G., ed. (1968) The Merck Index, 8th ed., Ray, NJ, Merck & Co., p. 808 Toth, B. & Shzu, H. (1974) l-Cabal-2-phenylhydrazine turrigenesis in Swiss mice. !-rpholog of lung adenorrs. J. nat. Cacer Inst., 52, 241-251

181 POlSIUH BIS (2-HYROXY) DITHIOCTE

1. Chemcal and Physical Data 1.1 Synonyr and trade nas

Cher. Abstr. Reg. Serial No.: 23746-34-1

Cher. Abstr. Nam: Bis (2-hydroxyethyl) carbaithioic acid, Ilnopotassium salt Bis (2-hydroxyethyl) dithocarbac acid, imnopotassium salt 1.2 Chemcal formula and imlecular weight HOCH2-CH2,,- Il S "" N-C-S K+ HOCH2-CH2/'

C5H10KN02S2 MoL. wt: 219.4

. 1.3 Chemcal and physical proprties of the pure substance

No data were available to the Working Group.

1.4 Technical products and imurities

No data were available to the Working Group.

2. Production, Use, Ocurrence and Analysis

For imrtant background inforrtion on this section, see prearle,

p. 15.

2.1 Production and use

Potassium bis (2-hydroxyethyl) dithiocarbate ca be prepared by the addition of carbon disulphide to an aqueous solution of diethanolarne and potassium hydroxide. No indication has æen found that it is produced in corrrcial quantities in the US or Euope. 'Io US companies offer it for research purses (Anon., 1975).

183 Potassium bis (2-hydroxyethyl) dithocarbate ca be used as an analytical reagent for the quantitative deterrtion of rrrcur, palladium (Usateno et al., 1971), gold (Gar et al., 1968), copper, cobalt and nickel (Balatre & Pinas, 1961; Pinas, 1960).

2.2 Occurence

Potassium bis (2-hydroxyethyl)dithocarbate is not know to occur as a natural product.

2.3 Analysis

NJ anlytical rrthods suitale for the deterrnation of potassium bis(2-hydroxyethyl)dithiocarbate in enviroI1tal sarles were available to the Working Group. A thn-layer chromatogaphic-spctrofluorimtric rnthod (van Hoof & Heyndrickx, 1973) is suitale for the analysis of a variety of rntal di thiocarbartes, al though i t was not applied ta

potassium bis (2-hydroxyethyl)dithiocarbamte itself.

3. Biological Data Relevant to the Evluation of Carcinogenic Risk ta Ma

3.1 Carcinogenicity and related studies in animls

(a) Oral admistration

Mouse: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F ITce and 1 18 male and 18 femle (C57BL/6xA)F mice received commrcial potassium bis (2-hydroxyethyl)dithiocarbate (purity1 unspeified) according to the following schedule: 464 rr!kg l: in gelatine at 7 days of age by stomach tub and the sar aiunt (not adjusted for increasing boy weight) daily up to 4 week of age; subseqently, the rnce v.re given 1112 rr potassium bis (2-hydroxethyl) dithiocbate per kg of diet. 'Ie dose was the maimum tolerated dose for infant and young mice but not necessarily so for adul ts . The expriint was tennnated when the mice were abut 78 weeks of age, at which tii 14, 17, 15 and 16 mice in the four groups, respecti vel y, were still ali ve. 'lur incidences were compred wi th those obsered aing 79-90 necropsied mice of each sex and strain, which ei ther had ben untreated or had recei ved gelatine onl y . Hepatonis were

184 found in 13/16 male and 12/18 femle (C57BL/6XC3H/An)F rnce, COed 1 with 8/79 and 0/87 controls, and in 13/17 male and 3116 femle (C57BL/6x AK)F mice, conied with 5/90 and 1/82 controls. Incidences of lung 1 adenors and malignt 1 yrhors w=re not greater than those in controls (Ines et al., 1969; NTIS,1968).

Rat: Results of a 2-year feeding study with potassium bis (2-hydroxyethyl)dithocarbamte in Chrles River m rats have æen reported briefly (Ulland et al., 1973) (The inadeqate reporting does not allo. an evaluation of this expimt J .

(b) Subutaeous adnnistration

Mouse: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F mice and 1 18 male and 18 femle (C57BL/6xA)F mice w=re given single s.c. injections of 464 ID::/kg l: cCJrcial fXtassium1 bis (2-hydroxyethyl)dithocarbate (purity unspecified) in dimthyl sulphoxide on the 28th day of life and were obsered until they were alut 78 w=eks of age, at whch tim 15, 15, 17 and 18 mice in the four groups, respecti vel y, wee still ali ve. 'lur incidences were conied with those in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. Inci- dences were not increased (P;:O. 05) for any tuur ty in any sex-strain suboup or in the cornined sexes of either strain (NTIS, 1968) (The WJrking Group noted tht a negative result obtained with a single s.c. injection may not be an adeqate basis for discounting cacinogencity J . 3. 2 Oter relevant biological data

No data w=re available to the WJrking Group.

3. 3 Case report an epidemological studies_

No data '.~;ers available ta tl:e Working Group.

185 4. Corrts on Data Reprted and Evaluation 1 4 .1 Animl data

Potassium bis (2-hydroxyethyl)dithiocarbate is cacinogenic in mice after i ts oral admnistration: i t induced li ver-ce 11 tuiurs in mIes of tw strains and in fenles of one strain. 4. 2 Hum data No case report or epidemological studies were available ta the Working Group.

lSee also the section, 'Anl data in relation ta the evaluation of risk to ma' in the introduction ta ths volur, p. 13.

186 5. References

Anon. (1975) Chem. Sources-USA, Flergton, ID, Directories Pulishing Co., p. 106

Balatre, P. & Pinkas, M. (1961) Sirultaneous coloriItric deterrnation of copper and nickel or copper and cobalt by using potassium bis (hydroxyethyl)dithiocarbate. Chir. analyt., 43, 433-438

Gars, Z.F., Tulyupa, F.M. & Usatenko, Y. 1. (1968) Potassium bis (2-hydroxy- ethy 1) di thiocarbarte, an arrorntric reagent for deterrning small amunts of gold (III). Opred. Miroprimsei, l, 72-77 van Hoof, F. & Heyndrickx, A. (1973) Thn layer chromatographic-spectro- photophuorirtric rnthods for the deterrnation of di thio- and thiolcarbates after hydrolysis and coupling with :ND-Cl. Ghent. Rijksuniv. Fac. Ladbl. Me., 38, 911-916

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrucelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Pet.ers, J. (1969) Bioassay of pesticides and indus trial chemcals for turrigenici ty in mice: a prelirnar note. J. nat. Cancer Inst., 42, 1101-1114

NTIS (National Techncal Inforntion Service) (1968) Evaluation of Carcino- genic, Teratogenic and Mutagenic Activities of Selected Pesticides and Industrial Chemcals, Vol. l, Cacinogenic Study, Washington IX, US Depatrt of Conmce

Pinkas, M. (1960) The use of potassium bis (hydroxyethyl)dithiocrbarte in the colorimtric deterration of copper, cobalt, and nickeL. BulL. Soc. pham. Lille, l, 93-97

Ulland, B., Weisburger, E.K. & Weisburger, J.H. (1973) Chronic toxicity and carcinogenici ty of industrial chercals and pesticides. Toxicol. appl. Pharcol., 25, 446 Usatenko, Y.I., Tulyupa, F.M. & Tkcheva, L.M. (1971) Use of potassium N, N-bis (2-hydroxyethyl)dithiocrbate for the anronetric deter- mination of nercur and palladium. Kh. Tekol. (Kharkov), 18, 150-154

187 PROPHA

1. Chcal and Physical Data 1.1 Synonyr and trade nas

Chem. Abstr. Reg. Serial t-b.: 122-42-9

Chem. Abstr. Nai: Phenylcabac acid, l-rrthylethyl ester

Carbailic acid isopropy 1 ester; IFC; IN; IP; Iso. PPC.; isopropyl cabalate; isopropyl cabailic acid ester; isopropyl phenylcabate; isopropyl N-phenylcabate; O-isopropyl N-phenyl carbate; N-phenylcabac acid isopropyl ester; N-phenyl isopropy 1 carbate Ba-Hoe; Beet-Kleen; CheHoe; IFK; Triherbide-IP; Turite; y 2 1. 2 Chemcal fonnla an rrlecular y.ight o CHi ~C---~H,HIl 1

C10H13N)2 MoL. wt: 179 . 2 1. 3 Chemcal and physical propeties of the substace

From Weast (1975), unless otrwse spified

(a) Description: Whte neeles

(b) Melting-point: 900C

(d) Spectroscoy data: À:r 236 nm and 274 nm (El - 46 and 942); for infra-red spectra, se Grasselli (1973) (e) Solubility: Insoluble in water at room temrature; soluble in rrst organic solvents (Stecher, 1968)

189 1.4 Technical products an imurities

Propham is available in the US as an emsifiable concentrate contain- lng alut 24% of the active ingredient, in granule forr containing 10% and 15%, as a flowable suspension containing alxmt 48% and as a wettale :ider containing 50% of the chemcal (Berg, 1975).

2. Production, Use, Occurrence and Anlysis For imrtat background info:ition on this section, see prearle, p. 15. 2. 1 Production and use

Prophar can be prepaed either by the reaction of phenyl isocanate wi th isopropy 1 alcohol or by the reaction of isopropy 1 chlorofo:ite wi th anline.

Propha was first produced comurcially in the US in 1946 (US Tariff Commssion, 1947; onl y one company now produces i t there (US Tariff Commssion, 1968). There have been no imrts into the US since 1971, when 2500 kg were imrted. Prophar is reported to te produced in The Netherlands and the OK (Berg, 1975) but not in Japa.

Its plant-graw reglatory properties were first reported in 1945 (Spencer, 1973), and it is used as a selective pre-planting, pre-emrgence and post-emgence herbicide. It effectively controls rny anua1 grassy weed and certain broadleaf weeds and is registered in the US for use on abut 12 forage, field and vegetale crops at residue tolerances ranging froID 0.1 to 5 mg/kg (US Envirorital Protection Agency, 1974).

Abut 200 thousand kg prophar were used on agricultural crops ln the US in 1971. More than half of the 60 thousand kg used in the state of Californa in 1974 was applied to sugar beets; a total of 30 thousand acres of cropland were so treated (California Deparnt of Fcx & Agri- culture, 1975). It was deterrnated from a questionnaire sent to a numr of herbicide rnufacturers tht a 'smll 1 aiunt of propham is used in ltaly as a patata sprout inhi tor .

190 2. 2 Occurrence

Prophar is not known to occu as a natural product. Residual aiunts rny be present on or in treated crops after harvesting. 2 . 3 Anal ysis

Several reviews include rnthods of analysis for prophar (Fishbin & Zielinski, 1967; Gad & Ferguon, 1964; Zweig & Sherm, 1972). Various methods of anal ysis sui table for prophar are describ in the rrnogaph on chloropropha (Burge & Gross, 1972; Frei & Laence, 1973; Laence & Laver, 1974, 1975). A thin-layer chromatogaphic rnthod for the identification of sixty-ori pesticides, including propham, is reported by Ebing (1972).

Colorimtric measuremnt of the alkaline distillation product may be adapted to the anl ysis of propham residues in a wide range of fruts and vegetables (Ferguon & Gard, 1969).

3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma

3.1 Carcinogenicity and related studies in animls

(a) Oral admistration Mouse: A group of 50 l2-we old mice (strain and sex unspecified) was fed 0.1% prophar (purity unspecified) in the diet for 18 rrnth, when the surivors were killed. The treatrnt produced signs of toxicity, and the anirls were retured to the norml diet at intervals. Fifteen mice were dead by 6 rrnths, and only 2 surived 12-18 rrnths. No tu:urs were observed. A further group of 50 ' C' rrice (25 of each sex) was fed O. 5 % propham in the diet for 18 rrnth, when the surivors ~re killed. The treatrnt produced signs of toxicity, and the animls were retured to the norml diet at intervals. 'Ienty mice were dead by 6 rrnths, and 16 surived 12-18 rrnths. No tururs were observed (Hueper, 1952).

Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F mice and 18 male 1 and 18 femle (C57BL/6xA)F mice recived propha (100% pure) according to 1 the fOllCJing schedule: 215 rrg/kg li in gelatine at 7 days of age by

191 storch tub and the sar arunt (not adjusted for increasing bcy weight) daily up to 4 wees of age; subseqently, the rnce \Vre given 560 Il propham per kg of diet. The dose was the ma talerated dose for infant and young mice but not necessaril y so for adul ts . The exriit was terrnated when the mice were aOut 78 \Veks of age, at which tim 11, 17, 14 and 16 mice in the four groups, resricti vel y, were still ali ve. Ttur incidences were corned with those observed arng 79-90 necroDsied mice of each sex and strain, which either had ben untreated or had received gelatine only: the incidences \Vre not significantly increased (P:;0.05) for any turur ty in any sex-strain subroup or in the coniined sexes of either strain (Innes et aZ., 1969; NTIS, 1968).

Rat: Fifteen 32-\Vek old Osborne-Medel rats (sex unspecified) \Vre fed 2% prophar (purity unpeified) (20 g/kg of diet), alterting with 1-2 wees of norml diet, for 18 rrnths, when the 8 suri vors were killed. No tururs were found; hcwever, histological exnation of only 6 rats was carried out (Hueper, 1952).

'Io groups of 9 white rats each received 10 Il propham (m.p. 870C) as a 3% oily solution daly in the diet for ia m:ths, or 15 mg as a 5% miure with kaolin pcder in the diet for 15 ITnths. Six rats of the second group and 3 of the first \Vre killed before 8 rrnths; rD lung tururs \Vre found

(Engelhorn, 1954).

Hater: A group of 23 mle and 26 femle 6-week old golden haters were fed 2 g prophar (m.p. abut 870C) i:r kg of diet for 33 rrnths and were cornared with an untreated group of 22 males and 27 femles. After 2 years, 6 treated and 1 control femle and 13 treated and 14 control males were still ali ve. Bile-duct hyprplasia of the li ver was observed in 28 treated animls and in 28 controls. A total of 6 tUlurS in different organs was seen in treated animls, cornred with 8 in controls (va Esch & Kroes, 1972).

(b) Subutaeous and/or intrarcular admnistration Mouse: Of 35 femle and 39 male 20-wee old C mice injected ln the right .ferral muscle with 400 Il/kg b. propham (purity unspecified) in o . 1 ml lanolin every second week for 6 rrnth and observed for a furer

192 year, onl Y 15 femes an 3 males suri ved 13 or rrre rrnths; no tmrurs were observed (Hueper, 1952).

Groups of 18 mae and 18 femle (C57BL/6xC3H/An)F imce and 18 male 1 and 18 femle (C57BL/6xA)F mice W2re given single s.c. injections of 1 215 mg/kg bw propham (100% pure) in dithyl sulphoxide on the 28th day of life and were observed until they were alut 78 wees of age, at which ti 16, 18, 17 and 17 mice in the four groups, respecti vel y, were still ali ve . Tuur incidences were conied with those ln groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. Inci- dences were not increased (P:;O. 05) for any tUIur ty in any sex-strain subroup or in corined sexes of either strain (NTIS, 1968) (The WJrking Group noted tht a negative result obtained with a single s.c. injection may not be an adeqte basis for discounting carcinogenici ty J .

Rat: Fifteen 24-wee old femle Osborne-Medel rats were injected in the right feral mucle wi th 400 mg/kg li propham (puri ty unspeified) in O. 2 ru lanolin once a ITnth for 6 rrnths and W2re observed for a furer year. Thee rats died before the l3th rrnth of the eximnt. Tuurs found in 4/10 necropsied rats were 1 adenofibroma in the region of the groin, 2 adenornoms of the uteru and 1 adenocarcinoma of the breast. One ma adenoma was found aIng 10 control rats (Hueper, 1952).

(c) Intraperitoneal injection Mouse: A group of 16 7-9-week old male A/He mice was given 12 i.p. injections of 5 mg/anim propham (purity unspecified) in tricaprylin over a peiod of 4 weeks and killed 20 W2ekS after the end of treatmt. Onl Y the incidence of lung tmrurs is reported: 1 was found in 1/10 suri vors, cored wi th 8 in 7/28 controls recei ving the sol vent onl y and 2 in 2/31 untreated mice; with a dose of only 3.2 mg, 2/14 surving mice develope 1 ung tmrurs (Shimin et a i ., 1969). (d) Oter exprimtal system

Intrapleural injection: A group of 30 mle and 30 femle C rnce was given repeted intrapleural injections of 400 ff/kg l: propha (purity unpecified) in 0.1 ml laolin every second W2ek for 6 rrnth. Ony 9

193 femles suri ved rrre th 13 rrnths. No tururs were observed, al though 2 femles had 'white nodular masses in the lungs' (Hueper, 1952).

A group of 15 20-week old male rats was gi ven repeted intrapleural injections of 400 mg!kg hw prophar (purity unspecified) in 0.2 ml lanolin rrnthl y for 6 rrnth. Onl Y 9 rats ~re autopsied; 6 of these li ved for less than 14 rrnth. No tururs v.re found (Hueper, 1952).

Oral admnistration wi th skin application of a prorting agent: Groups of 15 Swiss mice of each sex received propham (m.p. 840C) according to one of the follawng schedules: (1) a single dose of 15 mg/animl as a 1% solution in tragacanth given by storch tub; (2) 15 rr once v.ekly for 10 wee; or (3) 1 g/kg of diet (0.1%) for 6 rrth. Prartion was induced either with a 5% solution of croton oil in olive ail twice weeky or with undiluted Tween 60 given 6 tims/wek for 6 rrnths. Six rrnths after the star of the exriIt, the proportions of mice (males and femles considered together) wi th skin papillomas v.re as follow :

Propham Croton oil Tween 60

Papilloma- Papillomas Pa pi 1 loma- Papillors bearing per animl æaring per animl anls animIs 15 mg x 1 4/27 1.3 0/26 0.0 15 mg x 10 8/28 1.3 1/25 3.0 1 g!kg of diet 6/27 5.2 1/25 2.0 None 1/22 1.0 1/27 2.0 Animls wi th papillomas were observed for a furer 10 rrnth. A total of 65 papillors appeared during the 6 rrnth of treabnt plus 10 rrnth of observation in mice gi ven prophar and croton oil; 4 of these were still present 6 rrnth after the end of treatmt, and in 2 anls the paillan progessed ta cacinors. On Y 1 papillor wa see in controls reci ving croton oil onl y . ln rnce gi ven prophar and Tween 60, 5 papillors appared during the two periods. No skin tururs occurred in sirlar groups of mice given the prophar treatmnts without the croton oil or Tween 60 treabnts (va Esch et al., 1958).

194 ln a further exr.it, a group of 50 Swss mice of each sex received 15 mg/animl propha by storch tub 10 tims weely and then twice weekly cutaneous applications of croton oil for 26 ~s. It is reported that "a clear increase was observed in the nurr of males wi th pëpillors, and in both sexes, in the total nurr of papillomas. ln the males, two malignant tUIurs were present" (va Esch et al., 1965, reported in van Esch & Kroes, 1972). 3 .2 Oter relevant biological data (a) Exrimtal system

ln rats, the oral I. of prophar is 1-9 g!kg l: (Ben-Dyke et aL., 50 1970). Groups of mice were given 1-20 g propham per kg of diet for alut 18 rrnth. At levels of 1 and 5 g!kg of diet, animIs becam erciated, and sar died uness they v.re transferred from the prophamcontaining diet every 2 wees and fed the norml diet for a sirlar period; rrrtality was high in anls fed 10 and 20 g!kg of diet. Fifteen rats surived admnistration of 20 g prophar per kg of diet for 18 imnth when they were gi ven alterntely the prophamcontaining diet for 1-2 imnths and a norml diet for 1-2 weeks (Hueper, 1952).

After oral admstration of (isopropyi-14C)- and (ring-14C)-lablled propha to rats, the 3-day urinar excretions of herbicide-related rrterial represented 80 and 85% of the dose, respectively; in the case of the isopropy 1 - lablled corund, an addi tional 5 % of the dose was excreted as carbon dioxide via the lungs. There was no significant difference in the rate of excretion or elirati ve route aing rats recei ving oral doses ranging from 4-200 ff!kg lM. Herbicide-related material was distributed thoughout the boy, with highest concentrations in the kidneys. A srll degree of herbicide hydrol ysis occured in nearcin-treated rats, probal y in the li ver. Approximtel y 30 % of an i. v. dose of propham was excreted in the 6-hour bile (Bend et al., 1971; Fang et al., 1974).

ln a lactating goat given a single dose of 100 ff!kg l: prophar (1) (Scher 1), the urinar rrtablites included conjugates of isopropyl 4- hydroxycabalate (2), isopropy 1 3, 4-dihydroxycarbalate (3), isopropy 1 2-hydroxycabailate (4), (2-hydroxyisopropyl)-4-hydroxycarbanlate (5),

195 f- 1. 0"

SCHE 1

o Il COCHCHi-CH20H H1 CI o o .. Ho-~OCH(CH3J, __HOnNH, _HOnNHCOCH, \Ç7~OCH(H CHCD ,J, ~ HOH 0 ~ CI (j HO~7&iH(CH3J, H CI o \Q~~OCH(CH,J,OH CD OH _\QNH, CI 4-hydroxyaniline (6), 4-hydroxyacetailide (7) and 2-hydroxyaniline (8). Small aiunts of propham iætali tes v.re also excreted in the faeces and milk (Paulson et al., 1973). Sirlarly, in the urine of rats treated with propham (1) 80% of the dose occurred as the sulphate ester of isopropyl 4-hydroxycarbanilate (2) together with other conjugates (Bend et aL., 1971; Fang et al., 1974; Holder & Ryan, 1968; Paulson et al., 1973).

Prophar inhits spindle fibre formtion and induces ChrOISor abrrations in plants (Arr & Farah, 1974; Coss et aL., 1975). l\ reverse mutations were detected in Bacillus subtilis (De Giovani-Donnelly et aL., 1968) or in Salmonella typhimurium (Andersen et al., 1972); rntablic activation syste were not used in the tests on bacteria.

(b) Ma

No data were available to the Working Group. 3 . 3 Case reports and epidemological studies

No data were available to the Working Group.

4. COITnts on Data Reported and Evaluation

4.1 Animl data

ln one study in which prophar was admnistered orally to two strains of mice, no evidence of carcinogenici ty was observed. Oter studies in mice, rats and hamters by oral admnistration, in rnce and rats by subutaeous injection and in mice by intraperitoneal or intrapleural injection also shcwed no carcinogenici ty, but they were inadeqate ei ther in term of the ninr of suri ving animls, the total dose or the extent of patholog carried out. Oral 1 y admnistered propham acted as an ini tiator in tw-stage carcinogenesis studies ln mice. 4. 2 Hum da ta No case reports or epidemological studies were avai lable to the i\brking Group.

197 5. References

Air, S.M. & Farah, O.R. (1974) Cyological effects of T:sticides. '\TII. Mitotic effects of isopropyl-N-phenyl carbamte and 'Duphar'. Cytologia, 40, 21-29 Andersen, K.J., Leighty, E.G. & Takahashi, M.T. (1972) Evluation of herbicides for possible rntagenic properties. J. agric. Fd Cher. , 20, 649-656

Bend, J.R., Holder, G.M. & Ryan, A.J. (1971) Furer studies on the rrta- bolisr of isopropyl N-phenylcarbate (prophar) in the rat. Fd Cosmt. Toxicol., 9, 169-177

Ben-Dyke, R., Sanderson, D.M. & Noakes, D.N. (1970) Acte toxicity data for pesticides. Wld Rev. Pest. Control, 2., 119-127 Berg, G.L., ed. (1975) Far Chemcals Hadbk 1975, Willoughby, Ohio, Meister, p. D 113

Burge, W.D. & Gross, L.E. (1972) Determtion of IPC, CIPC and propanil and sorn rntablites of these herbicides in soil incubtion studies. Soil Sci., 114, 440-443 California Depatmnt of Foo and Agriculture (1975) Pesticide Use Report, 1974, Sacramto, p. 86

Coss, R.A., Bloogcx, R.A., BrCMer, D.L., Pickett-Heaps, J.D. & McIntosh, J .R. (1975) Studies on the rnchanisr of action of isopropyl N-phenyl carbamte. Exp. eell Res., 92, 394-398

De Giovani-Donnelly, R., Kolbye, S.M. & Greeves, P.D. (1968) Effect of IP, CIPC, sevin and zectran on Baci L lus subti i is . Exprientia, 24, 80-81 Ebing, W. (1972) Routinemthode zur dfuinschichtchromtogaphischen ldenti- fizierug der Pestizidrckstide aus den Klassen der Triazine, Carbamte, Harstoffe und Uracile. J. Chornt., 65, 533-545

Engelhorn, R. (1954) -tr den Einfluss des Athyl-Urethans und des Phenyl- arbamsäure-isopropylesters auf das Lungengeweb der Ratte. Arch. ex. Path. Pharol., 223, 177-181 van Esch, G.J. & Kroes, R. (1972) Long-terr toxicity studies of chloropropham and propham in mice and haters. Fd Cosrt. ToxicoL., 10, 373-381 van Esch, G.J., van Genderen, H. & Vink, H.H. (1958) The production of skin tururs in mice by oral treatmnt with urethane, isopropyl-N-phenylcarbate or isopropyl-N-chlorophenylcarbarte in combination with skin painting with croton oil and ~en 60. Brit. J. Cacer, 12, 355-362

198 Fang, S.C., Fallin, E., l.lontganry, H.L. & Free, V.H. (1974) Metalic studies of 1 4C_ 1ablled propha and ch10rpropham in the femle rat. Pest. Biocher. Physiol., !, 1-11

Ferguon, C. E. & Gard, L. (1969) IPC and CIP residue anal ysis . J. agric. Fd Chem., 17, 1062-1065 Fishbin, L. & Zielinski, W.L., Jr (1967) Chc:togaphy of cabartes. Chrnt. Rev., 9, 37-101

Frei, R.W. & Lawrence, J.F. (1973) Fluorigenic lablling in high-spe liqud chrc:tography. J. Chc:t., 83, 321-330

Gard, L.N. & Ferguon, C.E., Jr (1964) IPC. ln: Zw=ig, G., ed., Analytical Methods for Pesticides, Plant GrowRegators and Fcx Additives, VoL. 4, Herbicides, New York, Academc Press, pp. 139-145

Grasselli, J.G., ed. (1973) Atlas of Spectral Data and Physical Constats for Organc Coninents, Cleveland, Ohio, Chcal Rur Co., p. B-400

Holder, G.M. & Ryan, A.J. (1968) Metalisrn of prophar (isopropyl N-phenylcarbate) in the rat. Nature (Lond.), 220, 77

Hueper, W. C. (1952) Cacinogenic studies on isopropy 1 -N-pheny 1 -carbate. Industr. Med. Surg., 21, 71-74

Innes, J .R.M., Ulland, B.M., Valerio, M.G., Petrcelli, L., Fishbin, L., Hat, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gar, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides

and indus trial checals for tUlrigenicity in mice: a prelirar note. J. nat. Cancer Inst., 42, 1101-1114

Lawrence, J.F. & Laver, G.W. (1974) Anlysis of cabate and urea herbicides in foo, using fluorogenc labling. J. Ass. off. analyt. Chem., 57, 1022- 1025

Lawrence, J.F. & Laver, G.W. (1975) Anlysis of sorr carbate and urea herbicides in fcxs by gas-liqud chramtogaphy after alklation. J. agric. Fd Cher., 23, 1106-1109

NTIS (National Technical Informtion Service) (1968) Evluation of Cacino- genic, Teratoenic and Mutagenic Acti vi ties of Se1ected Pesticides and rndustrial Chemcals, Vol. l, Cacinogenic Study, Washington IX, US Depat of Conmrce

Paulson, G.D., Jacobsen, A.M., Zaylskie, R.G. & Feil, V.J. (1973) Isolation and identification of propha (isopropyl cabailate) rrtallites frcm the rat and goat. J. agric. Fd Chem., 21, 804-811

199 Shirin, M.B., Wieder, R., HcDonough, M., Fishbin, L. & S~rn, D. (1969) Lung hmDr response in strain A rnce as a quti tati ve bioassay of carcinogenic acti vi ty of sone carbates and aziridines. Cancer Res., 29, 2184-2190 Spencer, E. Y. (1973) Guide to the Chemcals Used in Crop Protection, 6th ed., Ladon, Ontaio, Unversity of Western Ontaio, Research Branch, Agriculture Canada, Publication 1093, p. 431 Stecher, P .G., ed. (1968) Th Merck Index, 8th ed., Raway, NJ, :Mrck & Co., p. 575 US Environmtal Protection Agency (1974) ~A Comdium of Registered Pesti- cides, Washington De, US Governt Printing office, pp. 1-1-5.1-1-1-5.3 US Tariff Coimiission (1947) Synthetic Organic Chcals, US Production and Sales, 1946, Report No. 159, Second Series, "lashington De, US Govern- rnnt Printing Office, p. 135

US Tariff Commssion (1968) Synthetic Organic Chemcals, US Production and Sales, 1966, TC Pulication 248, Washington IX, US Governnt Printing Office, p. 178 Weast, R.C., ed. (1975) CRC Handbk of Chemstry and Physics, 56th ed., Cleveland, Ohio, Chemcal Rubber Co., p. C-232

Zweig, G. & Shern, J. (1972) IPC. ln: Z~ig, G., ed., Analytical Methods for Pesticides, Plant GrowReglators and Fcx Additives, VoL. 6, Gas Chonatographic Anlysis, NEW York, Academc Press, pp. 657-658

200 n-PROPYL CATE

1. Chemcal and Physical Data 1.1 Synonyr and trade nas

Cher. Abstr. Reg. Serial No.: 627-12-3 Cher. Abstr. Nam: Cabac acid, propyl ester

Propyl carbate; propyl urethane 1. 2 Chercal fonna and rrlecular v.ight

o Il H2N-C-O-CH2-CH2-CHi

C4H9N02 MoL. wt: 103.1 1. 3 Chemca and physical properties of the substace

From Weast (1975), unless oterwise spified

(a) Description: Prisr o (b) Boiling-point: 1960C; 92-92.5 C at 12 mm

(d) Spectroscopy data: For infra-red spctral data, see Grasselli (1973)

(e) Solubility: Soluble in water, ethol and diethyl ether (Prager & Jacobson, 1921)

(f) Volatility: Vapour pressure 1S 1 nm at 52.40C (Jorda, 1954). 1. 4 Technical products and Í1uri ties

No data were available ta the Working Group.

201 2 . Production, Use, Occurrence and Anl ysis

For :irtat background informtion on this section, see preanle, p. 15.

2 . 1 Production and use

n-Propyl carbate was first svnthesi7:ed 0y heatinq urea with excess propyl alcohol by Caours in 1873 (Prager & Jacobson, 1921). It can be prepared by treatin: n-propyl alcohol with CYa.en chloride in the presenc of hydchloric acid (Fus & Hari, 1973) .

Commrcial production of n-propyl carbarte was first reported in the US in 1966 (US Tariff Commssion, 1968). Production by one maufacturer ID 1972 was estirted to be 45 thousand kg; one manufacturer reported production in 1973 (US International Trade Comssion, 1975).

Propyl carbate (isorr unspeified) is believed to be used as a chercal intenædiate in the maufacture of dithylol propyl carbamte- based resins which are used in the textile industry as durable-press fabric finishes for cotton and polyester/cotton blends. Textiles treated with these resins have irroved durabili ty and wash-and-wear properties (Raunda et al., 1973). 2. 2 Occurrence

n-Propyl carbate ls Ilt knc: to occur as a natural product. 2 . 3 Anal ysis

Methods for the chromatographic anal ysis of cabartes, including alkyl carbates, have ben reviewed (Fishbin & Zielinski, 1967). A gas chromtogaphic rrthod has been described for detection of micrograr arunts of n-propyl carbate in a mixture of alkl carbates after the formtion of their trimthylsilyl derivatives (Ner, 1969). A thin- layer chrantogaphic rrthod for the separation of short-chain alkl carbates on silica gel with a corlex solvent system has been reported (Knappe & Rohdewald, 1966). The separated rnterials from this procedure are identif ied by hydrol ysis and conversion to the 3, 5-dini tro- bezoate deri vati ve (Valk & Schliefer, 1967).

202 3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma

3.1 Carcinogenicity and related studies in anirls

(a) Intraperitoneal admnistration

Mouse: A group of 32 10-12-week old strain A rnce (approxitely eqally divided by sex) were given 13 weekly i.p. injections of 0.5 mgl mouse commrcial n-propyl carbate (purity unspecified) and were killed 2 wees after the end of the trea trt, when they v.re 6 nonths old: 19 develope lung tumours, wi th an average of O. 9 tururs/nouse. An additional group of 46 mice received the sa treatmt with recrystallized n-propyl cabate¡ lung tUIurS develope in 30 animls, with an average of 1. 0 lung turur/rruse. LUl1g tururs v.re found in 24/141 untreated controls, with a rnan of 0.18 tururs/rruse (Lasen, 1947) (P-cO.001J.

A group of 52 6-8-week old C57BL6 mice (approxirtely eqally divided by sex) received 10 weekly i. p. injections of 570 mc:J/kg bt n-propyl carbate (purity unpecified) and were autopsied 62 ~eks after the start of treatrnt. One rruse died wi th leukaera at 17 weeks ¡ 7/44 rnce which suri ved to the end of the exprirnt developed lung adenomas (P:;O. 05) , wi th an average of 0.2 tururs/rruse. Of another group, which had been expsed also to total boy irradiation with 400R 1 v.ek before the chercal was adristered, 3/50 mice died with leukaema withn 38 weeks. Of untreated controls, 9/75 developed lung adenomas¡ the incidence of leukaera in this strain was reported to be 0.7% (Mirvish et al., 1969).

A group of 17 6-8-week old Swss rnce (approximtely eqally divided by sex) received 5 weekly i. p. injections of 570 rr/kg l: n-propyl carbate (purity 80-100%) in water and were killed 14 nonths after the start of the exprimt. ln another group of 38 rnce, this treatrnt was follcwed one week later by twce vvekly skin applications of 5% croton oil in liquid paraffin for 40 weeks¡ the surivors v.re killed 14 nonths after the star of the exprirnt. No skin tUIurS ~re found in ei ther group. 'I mice treated with n-propyl carbarte plus croton oil died with leukaera, cornared with 0/50 controls given crotan oil only. At the end of the exrirnt, 16 of a total of 21 surivors that had received n-propyl carbarte (with or without

203 subseqent croton oil treatint) had lung adenomas (average, 1. 5 ti.urs per rruse). The incidence of lung adenomas in controls given croton oil only was 3/17, with an average of 0.4 ti.urs/rruse (Mirish et aL., 1969).

A group of 16 7-9-wee old male A/He mice were given 12 i.p. injections of 5 mg n-propyl carbante in tricaprylin over a pericd of 4 \\eks and VJre killed 20 weeks after the end of treatmt. Ony incidences of lung ti.urs were reported: lung adenomas (1 adenoma/animl) \\re found in 9/12 mice given n-propyl carbate, in 7/28 mice given the solvent only (one muse with 2 tururs) and in 2/31 untreated controls (Shiin et al., 1969).

(b) Oter exprimtal system

Oral admistration and skin proIItion: A group of 20 8-l2-wee old Swiss mice received a single oral admnistration of 25 mg n-propyl carbamte in water, follo\\d 4 days later by twce-\\ekly applications of a 5% solution of croton oil in liquid paraffin on the dorsal skin for 40 \\eks. Within 20 weeks, 3/15 surivors developed skin tururs (average, 0.2 hnmurs/rruse), compared with 3/45 (0.07 tururs/IIuse) in controls treated with croton oil only. By the end of the treatmt, 4/14 anirls had develope skin ti.urs (0 . 3 skin ti.urs/rruse), compared wi th 11/44 (O. 4 skin ti.urs IIIuse) in the croton oil-treated control groupa Lung adenorns were found in 4/14 animls of the exprirtal group and in 2/42 of the croton oil-treated controls (Berenli. et al., 1959).

Subutaeous injection and skin prortion: A group of 40 7-week old male 'Hall' mice were given single s.c. injections of 20 rn n-propyl carbate in saline. Treatmnt was follCMed 2 \\eks later by 24 \\ekly cutaneous applications wi thin 26 \\eks of 0.25 ml of a 0.07 % solution of croton oil in acetone. Of 26 mice injected with n-propyl cabate and still ali ve 1 week after the end of the croton oil treatmnt, 5 developed skin tururs (1 ti.ur/IIuse). Of controls receiving croton oil only, 2/41 develope a total of 3 skin tururs. No ti.urs occured in mice that received a single injection of n-propyl carbate and were observed for 26 weeks (Pound, 1967) (P?O. 05 J .

Injection and skin prorrtion: ThD groups of 29 and 27 7-~k old rnle 'Hall' mice were given a single injection (route unspecified) of 7.7 rng

204 bw n-propyl carbate. Eighteen hours before this treatint, th second group received an application of 0.24 ml of a 0.075% croton oil solution in acetone over the whole area of the dorsal skin. Thee wes later, bath groups were given 32 weekly treatmts with croton oil, each application consisting of 0.24 ml of a 0.075% solution in acetone during the first 18 wees and 0.15% for a further 14 v.eks. A control group of 90 Mce recei ved croton oil onl Y . The nunrs of mice wi th skin tururs still ali ve at 36 wees were 3/24 in the group which had had no prelirnar croton oil treat- IDnt, 3/27 in the second group and 8/86 in controls. The nuns of skin tururs, hepatomas, li ver haiorr, lung aderos or leukaeras were not statistically increased in mice that surived up to 78 weeks, in cornarison to controls (Pound & Lawson, 1976). 3.2 Oter relevant biological data (a) Exrimntal system The s. c . ID of n-propy 1 cabate ln rrce 1S 1. 3 g/kg l: (Pound, 50 1967) . Rats injected intraperitoneally with n-propyl cabate or the corresponding IV-hydroxycarbamte . excrete bath the carbate and N-hydroxycarbate in the urine (Boyland & Ner, 1965). Th binding of (14C-propylJ- n-propyl carbamte to the DNA of muse liver was very lCM coared with that of (14C-ethyl)-ethyl carbate (Lason & Pound, 1973). Pregnat Syrian haters were injected intraperitoneally on day 8 of gestation with n-propyl carbate or one of a series of strcturally-related carbamates. ln foetuses exared on day 13 of gestation, the effects of n-propyl carbamte were comared v-7Ìth those of urethe; it was found (i) to have ben as teratogenic, (ii) to have given the sar kind of malfor- mations and (iii) to have retaded grCM to the sar extent. The nurrs of dead foetuses and resorptions that v.re produced by treatrnt wi th propyl and ethyl cabates were sirlar (DiPaolo & Elis, 1967) .

No reverse mutations were induced in Baci i lus subti lis (De Giovani- Donnelly et al., 1967); rrtablic activation system were not used in this test.

205 (b) f.13

tb data were available to the Working Group. 3. 3 Case reports and epidemological studies

No data were available to the Working Group.

4. Conmnts on Data Reported and Evaluation 1 4.1 Animl data n-Propyl carbate is carcinogenic ln ITce after its intraperitoneal injection: it produced lung adenorrs in thee different strains (For a cornarison with ethyl carbate (urethane), see IAC (1974) J. 4.2 Hur data tb case reports or epidemological studies were available to the Working Group.

lSee also the section, 'Animl data in relation to the evaluation of risk to ma' in the introduction to ths volum, p. 13.

206 5. References

Berenblur, L, Ben-Ishai, D., Haran-Ghera, N., Lapidot, A., Simn, E. & Trainin, N. (1959) Skin initiating action and lung cacinogenesis by derivatives of urethane (ethyl cabarte) and related coITunds. Biocher. Pharcol., 2, 168-176

Boyland, E. & Nery, R. (1965) The netalisr of urethane and related cornunds. Biochem. J., 94, 198-208

De Giovani-Donnelly, R., Kolbye, S.H. & DiPaolo, J.A. (1967) Effect of carbates on Baci L lus subti lis. ~iitation Res., 4, 543-551

DiPaolo, J .A. & Elis, J. (1967) Th conparison of teratogenic and carcinogenic effects of sor cabate cornunds. Cacer Res., 27, 1696-1701 Fishbin, L. & Zielinski, W."L., Jr (1967) Chrortography of carbamtes. ChroI1t. Rev., 9, 37-101

Fus, R. & Hartemnk, M.A. (1973) Acid-catalysed reaction of cyanogen chloride with aliphatic alcohols. Geeral sythesis of aliphatic carbates. BulL. Soc. chir. belg., 82, 23-30 Grasselli, J .G., ed. (1973) Atlas of Spectral Data and Physical Constats for Organic Cornunds, Cleveland, Ohio, Chemcal Ruber Co., p. B-398 lAC (1974) lAC l-nogaphs on the Evaluation of Cacinogenic Risk of Chemcals to Ma, 7..-, Sorn Anti -thyroid and Related Substances, Ni trofuran and Industrial Chemcals, Lyon, pp. 111-140 Jordan, T .E. (1954) Vapor Pressure of Organc Cciunds, New York, Interscience, pp. 179, 192

Knappe, E. & Rohdewald, 1. (1966) Dünnschichtchromatogaphie von substituier- ten Hatoffen und eiachn Uret.en. Z. anlyt. Chem., 217, 110-113

Larsen, C.D. (1947) Evaluation of the cacinogenicity of a series of esters of cabac acid. J. nat. Cacer Inst., 8, 99- 10 1

Lawson, T.A. & Pound, A.W. (1973) The interaction of cabon-14-1ablled alkl carbates, lablled in the all and cabonyl positions, with DNA in vivo. Chem.-bioL. Interact., ~, 99-105 Mirvish, S.S., Chen, L., Haran-Ghera, N. & Beenlur, 1. (1969) Conparative study of lung carcinogenesis, promting action in leukaerenesis and ini tiating action in skin tuirigenesis by urethane, hydrazine and related cornunds. Int. J. Cancer, i, 318-326

207 Nery, R. (1969) Gas-chromatogaphic deteration of acetyl and trimthylsilyl derivatives of alkyl cabates and their N-hydroxy derivatives. Analyst, 94, 130-135

Pound, A.W. (1967) The initiation of skin tllurs in mice by homlogues and N-substituted derivatives of ethyl carbarte. Austr. J. exp. BioL. rnd. Sci., 45, 507-516

Pound, A.W. & Lawson, T.A. (1976) Cacinogenesis by cabac acid esters and their binding to DNA. Cancer Res., 36, 1101-1107

Prager, B. & Jacobson, P., eds (1921) Beilsteins Handbuch der organischen Cheme, 4th ed., VoL. 3, Syst. No. 201, pp. 28-29

Raunda, A.J., Adam, P., Beinfest, S. & Gulakawski, T.A. (1973) Treatrnt of cellulosic fibr-containing fabrics to imrove their physical characteristics. US Patent 3,752,697, Augut 14, to Millrster Onyx Corp .

Shirin, M.B., Wieder, R., McDonough, M., Fishbin, L. & Svrn, D. (1969) Lung tllr response in strain A rnce as a quanti tati ve bioassay of carcinogenic activity of sone cabates and aziridines. Cacer Res., 29, 2184-2190 US International Trade Corrssion (1975) Synthetic Organic Chcals, US Production and Sales, 1973, ITC Pulication 728, lvashington IX, US Governt Printing Office, p. 218

US Tariff Corrssion (1968) Synthetic Organic Chercals, US Production and Sales, 1966, TC Pulication 248, Washington IX, us Governnt Printina Office, p. 178

Valk, G. & Schliefer, K. (1967) Trennung und Nachweis von cyclischen Harstoff- Derivaten und Carbaten sawie deren Hydrolyseprodukten durch Dfuschicht- chromtographie. Texilindustrie, 69, 783-786 Weast, R.C., ed. (1975) CRC HandJk of Chstry and Physics, 56th ed., Cleveland, Ohio, Chemcal Ruber Co., p. C-23l

208 SEMCAIDE (HYROCRIDE)

1. Chercal and Physical Data

1.1 Synonyr and trade nais

Cher. Abstr. Reg. Seri al No.: 563-41-7

Cher. Abstr. Nai: Hydrazinecarboxarde rnnohydrochloride

Amdourea hydrochloride¡ amourea hydrochloride¡ carbalhydrazine hydrochloride¡ semicarbazide rrnohydrochloride 1. 2 Chemcal formla and molecular weight o H2N-NH-C/ "' NH2 . HCI æ6C1N30 MoL. wt: 111. 5 1. 3 Chercal and physical properties of the substance

From Weast (1975), unless otherwise spcified

(a) Description: Prisr

(b) Melting-J:int: l75-l770C (with decorsition) (c) Spectroscopy data: rnÀ = 278 nI and 3571 nI (El = 0.5 and 1.1) in water¡ for infra-red spctral data, see Grasselli (1973)

(d) Solubility: Soluble in water¡ very slightly soluble in hot ethanol¡ insoluble in anydrous ether (Stecher, 1968) 1. 4 Technical products and inuri ties

Semcarbazide hydrochloride is available CXrciall y in the US in chemcally pure and technical grades (Hawley, 1971).

209 2. Production, Use, Occurrence and Anal ysis

For imrtant background informtion on this section, see preamle, D. 15. 2. 1 Production and use

The first reported preparation of secarbazide hydrochloride was by reaction of benzylidenesemcarbazide with hydrochloric acid (Thiele & Stange, 1894). It can also be produced by the electrochemcal reduction of nitrourea in aqueous hydrochloric acid (Korczynski, 1969). The nethod used for commrcial production is not known.

Commrcial production of sercarbazide hydrochloride was first reported in the US in 1940 (US Tariff Commssion, 1941); in 1974, one maufacturer reported production (US International Trade Commssion, 1975). It is produced in the OK for research Durses.

Sercarbazide hydrochloride has been used as a chemcal reagent in the qualitative deterrnation of aldehydes and ketones (Stecher, 1968) and in the isolation of hormnes and of certin fractions froID essential oils (Hawley, 1971). 2. 2 Occurence

Semcarbazide hydrochloride is not know to occu as a natural product. 2. 3 Anal ysis

A potentioitric nethod for the rrasuremnt of sercarbazide hydrochloride, sensitive to at least 0.3 m:, has been describ (Pszonicka & Skwara, 1970).

210 3. Biological Data Relevant ta the Evluation of Carcinogenic Risk to Ma 1

3.1 Carcinogenicity and related studies in animls

(a) Oral admnistration

Mouse: An unspecified nurr of 6-8-we old femle dd mice were fed a diet containing 0.1% sercarbazide hydrochloride for 7 rrnths. At the end of treatrnt, 8 surivors v.re killed and examed for lung tururs : 6 mice had a total of 8 1 ung tururs, corred wi th 1 turur in 20 controls (Mari et al., 1960) (P~O.OOlJ.

Commrcial semcarbazide hydrochloride was admistered to 25 male and 25 femle 6-wek old Swiss mice for lifetim as a 0.0625% solution in the drining-water. The average daily intaes were 3.3 ng/ferle and 4.8 mg/male; lifespan was reduced in treated males. ln femles, 37 lung tururs occurred in 25/50 treated anls (0.7 tururs/rruse), compared with 31 in 21/99 femle controls (0.3 tururs/rruse) (P~O.OOlJ; there was no increase in the incidence of lung tururs in treated niles. Tuurs of vascular origin v.re observed at various sites in 9/50 treated ferles, compared with 5/99 fenle controls (p~O. 02), and in 3/50 treated males (4 tururs), cornared with 6/99 male controls (P)-0.05J. The 13 bloo-vessel tumurs in treated mice included 6 angiosarcos and 2 angiomas of the liver. Other tumurs \Vre eqally distributed arng treated and control mice (Toth & Shirzu, 1974; Toth et al., 1975).

Rat: A 2-year feeding study with sercarbazide in Chrles River CD rats has been describd (Ulland et aL., 1973) (The inadeqate reporting does not allow an evaluation of this exrimt J .

lSemcarbazide is a hydrazine derivative. For a discussion of hydrazine and related substaces, see IAC (1974).

211 3.2 Oter relevant biological data

(a) Exrimental system

The s.c., i.p., i.v. and oral LD doses for semcarbazide in mice 50 range from 123-176 mg/kg bw. The corund is a convulsant (Jeney & Pfeiffer, 1958).

The offspring of pregnant rats treated orally with sercarbazide during pregncy had facial abnormli ties, including rncrogathia and ) cleft palates (Stivers et al., 1971).

Admnistration of 50 or 100 mg/day to pregnant Sprague-Dawley rats on days 10-16 of gestation produced a high incidence of resorption in the dam and of cleft palates in the pups. Susceptibility of dam to cleft palate in offspring was greatest on days 12-15 of gestation (Steffek et al., 1972).

Sercarbazide hydrochloride binds to cytosine residues in RN, to deoxycytosine residues in DNA in vi tro and to cytosine and deoxycytosine nucleosides (Hayatsu & Ukita, 1966; Hayatsu et al., 1966). (b) Ma

No data were available to the Working Group.

3.3 Case reports and epiderological studies

No data were available to the Working Group.

4. Conints on Data Reported and Evaluation 1 4 . 1 Animl data

Semcarbazide hydrochloride is cacinogenic ln rnce after its oral admnistration: it prcxuced angiomas, angiosarcomas and lung tururs.

lSee also the section, 'Animl data in relation to the evaluation of risk to ma' in the introduction to this volur, p. 13.

212 4. 2 Hum data

No case reports or epiderological studies were available to the Working Group.

213 5. References

Grasselli, J .G., ed. (1973) Atlas of Spectral Data and Physical Constats for Organic Cornunds, Cleveland, Ohio, Checal Rubber Co., p. B-89l

Hawley, G.G., ed. (1971) Condensed Chemcal Dictionar, 8th ed., Ne. York, Van Nostrand-Reinold, p. 779

Hayatsu, H. & Uki ta, T. (1966) Moification of nucleosides and nucleotides. IV. Reaction of semcarbazide with nucleic acids. Biochi. biophys. acta, 123, 458-470 Hayatsu, H., Takeishi, K.1. & Ukita, T. (1966) Moification of nucleosides and nucleotides. III. A selective rrification of cytidine with semcarbazide. Biochir. biophys. acta, 123, 445-457 lAC (1974) lAC M::mographs on the Evluation of Carcinogenic Risk of Chemcals to Ma, 4, Sone Arorrtic Amnes, Hydrazine and Related Substaces, N-Nitroso Cornunds and Miscellaneous Allating Agents, Lyon, pp. 127-136

Jeney, E.H. & Pfeiffer, C.C. (1958) The convulsant effect of hydrazides and the antidotal effect of anticonvulsants and metablites. J. PhacoL. ex. Ther., 122, 110-123

Korczynski, A. (1969) Continuous electrochercal production of semcarbazide hydrochloride. Zesz. Nauk. Politech. Slask., Cher., 50, 189-191 !-ri, K., Yasuno, A. & Matsurto, K. (1960) Induction of pulnary turrs in mice with isonicotinic acid hydrazid. Ga, 51, 83-89

Pszonicka, M. & Skwara, W. (1970) The use of Co (III) solutions in acetic acid for oxidiretric titrations. IV. Potentiorntric deterrnation of sone derivatives of hydrazine, ascorbic acid and cysteine. Cher. analyt. (Warsaw), 15, 175-182 Stecher, P. G., ed. (1968) The Merck Index, 8th ed., Raay, NJ, Merck & Co., p. 941

Steffek, A.J., Verruio, A.C. & Vvatkins, C.A. (1972) Cleft palate in rodents after maternl treatrnt with various lathyrogenic agents. Teratology, 5, 33-40

Stivers, F.E., Steffek, A.J. & Yarington, C.T., Jr (1971) Effect of lathy- rogens on developing mid-facial structures in the rat. J. surg. Res., 11., 415-420 Thiele, J. & Stange, O. (1894) übr Secarbazid. Chem. Be., 27, 31-34

214 Toth, B. & Shirzu, H. (1974) l-Cabal-2-phenylhydrazine turrigenesis in Swiss mice. Morpholog of lung adenomas. J. nat. Cacer Inst., 52, 241-251

Toth, B., Shizu, H. & Erickson, J. (1975) Carbalhydrazine hydrocloride as a lung and bloo vessel tUIur inducer in Swss mice. Euop. J. Cacer, 11, 17-22

Ulland, B., Weisburger, E.K. & Weisburger, J.H. (1973) Chonic toxicity and carcinogencity of industrial chemcals and pesticides. Toxicol. appL. PharcoL., 25, 446

US International Trade Cornssion (1975) Synthe tic Organic Chercals, US Production and Sales, 1973, IT Pulication 728, t'lashington IX, US Governt Printing Office, p. 218

US Tariff Cornssion (1941) Sythetic Organic Chcals, US Productior. and Sales, 1940, Report No. 148, Seond Series, Washington OC, US Governnt Printing Office, p. 57

Weast, R.C., ed. (1975) CRC Handbk of Chstry and Physics, 56th ed., Cleveland, Ohio, Chemcal Ruber Co., p. C-489

215 SODIU DIElITHI~.MTE

1. Chemcal and Physical Data 1. 1 Synonyr and trade nas

Cher. Abstr. Reg. Serial No.: 148- 18-5 Cher. Abstr. Nar: Diethylcarbaithoic acid, sodium salt DED; diethyldithiocabate sodium; diethyldithocarbamc acid sodium salt; N, N-diethyldithiocarbac acid, sodium salt; diethyl sodium dithocarbate; dithiocarb; soum DED; sodium N~ N- diethyldithocarbac acid; sodium salt of N~ N-diethyldithiocarbac acid 1 . 2 Chemcal formula and molecular weight

CHi-CHz S ,-, N-C-SIl Na+ CHi-CHz/

C5H10NNaS2 !-l. \vt: 171. 3 1. 3 Chemcal and physical properties of the substace

From Stecher (1968), unless otherwse spcified

(a) Description: Platelets (Koch, 1949)

(b) M=lting-p:Ünt: 94-960C (c) Spectroscopy data: Àrn = 257 nm and 290 nm1 (El - 700 and 760) (Koch, 1949)

(d) Solubility: Freely soluble in water at room terrature; soluble in ethanl

(e) Staility: Aqueous solutions dec:rse slowly.

217 1. 4 Technical products and imuri ties

Sodium diethyldithocarbate is available ln the US for use in ruber procssing as a 25% active aqueous solution, with, tyically, a pale yellow colour and a density of 1.08-1.10 (Anon., 1975).

2. Production, Use, Occurence and Analysis

For imrtt background informtion on this section, see preale, D. 15. 2 . 1 Production and us The first reported prepaation of soum diethyldithiocarbate was by the addition of carbon disulphide to an aqueous solution of diethylarne and sodium hydroxide (Delepine, 1907). The sa rrthod is believed to be used for its commercial production (Tisdale & William, 1934).

Comærcial production of sodium diethyldithocbate was first reported in the US in 1940 (US Tariff Commssion, 1941). ln 1969, three maufacturers reported sales of 65 thousand kg (US Tariff Comssion, 1971). ln 1974, one maufacturer reported production (US International Trade Commssion, 1975).

It is estiated that less than 1 million kg soum diethyldithiocarbate are produced anuall y in Austria, the Beelux countries, France, the Federal Republic of Genry, ltaly and the UK.

This cc:und is used in the ruber-processing industr as a late accelerator (Anon., 1975). It is also used as a chemcal intenate in the production of other diethyldithiocarbate rrtal salts, such as the zinc, selenium and tellurium salts, and of bis (thiocbayl)sulphides, which are used as ruber-processing accelerators and fungicides (Shver, 1968). It is used to sepaate coppr from other netals (Steher, 1968); other miscellaneous applications include its use as an oxidation inibitor (Hawley, 1971), a chelating agent and as an analytcal reagent (Stecher, 1968) . It has been used as a chelating agent in hUJ therapy, for the treatInt of nickel carl:x:myl poisoning (Sunder, 1964).

218 2 . 2 Occurrence

Sodium diethyldithocarbate iS not kno. to occur as a natural product.

2.3 Anal ysis Concentrations of 5 x 10-5 - 8 x 10-4 M di thiocarbates have been anal ysed by direct-cuent polarographic rrthods in which ancxic waves correspond to the formtion of rrrcur co:runds (Halls et al., 1968); when short, control1ed drop tims are used, concentrations of 1.6 x 10-3 M can be deterred by this rrthod (Canterford et aL., 1973). The application of differential pulse polarography has increased the sensitivity of the rnthcx to a detection lirt of 1 x 10-6 M and a quantitative limt of 2 x 10-6 M (Caterford & Buchanan, 1973).

Scxium diethyldithiocarbate can be detened by titration of the excess iodine solution resulting froID the sodium diethyldithocarbate- induced iodine-azide reaction. The range which could be deterred was from 5-160 wg in 50 or 100 cm3 of solution, with a relative error of l3% (Kurzawa & Kubaszewski, 1974).

A thin-layer chrortographic-spctrofluorimtric rrthod (van Hoof & Heyndrickz, 1973) ls suitale for the analysis of a variety of rrtal dithiocarbates, although it was not applied to soium diethyldithiocarbate itself.

3. Biological Data Relevant ta the Evaluation of Carcinogenic Risk to Man

3.1 Carcinogenici ty and related studies in animls

(a) Oral admistration

!-use: Groups of 18 iæle and 18 femle (C57BL/6xC3H/An)F rmce and 1 18 male and 18 femle (C57BL/6xA)F rnce received soium diethyldithio- 1 carbate (m.p. 94-960C) according ta the followng schedule: 215 mg/kg bw in water at 7 days of age by stomach tub and the sar arunt (not adjusted for increasing l:y weight) daily up to 4 v;eks of age i subseqently, the rnce were given 692 !T sodium diethyldithiocarbate per

219 kg of diet. The dose was the ffirum tolerated dose for infant and young mice but not necessarily sa for adults. Th exrirt was terrnated when the anls were abut 78 wes of age, at whch tir 17, 18, 18 and 16 rnce in the four groups, respectively, were still alive. Tuur incidences ~re comped with those in 79-90 necropsied mice of each sex and strain, whch either had been untreated or had received gelatine. Pulm::mar adenomas occued in 3/17 (p?O. 05) and 5/18 (P~O. 05) maes of the two strains, respectively, comed with 5/79 and 9/90 in controls. Hepatomas develope in 7/17 maes of the first strain, conpared with 8/79 in control maes (P~O. 01) . There was no increase in the incidence of li ver tururs aIng maes of the other strain, and no li ver tururs occurred in ferles (Ines et al., 1969; NTIS, 1968). (b) Subtaeous admnistration

Mouse: Groups of 18 male and 18 fenle (C57BL/6xC3H/An)F rnce and 18 male and 18 femle (C57BL/6xA)F mice were given single s.c.1 injections 1 of 464 rn/kg l: scxium diethyldithocbate (m.p. 94-960C) in water on the 28th day of life and were observed until they were abut 78 weeks of age, at which tir 16, 18, 18 and 16 rnce ln the four groups, respctively, wee still ali ve. Tuur incidences were coared wi th those in groups of 141, 154, 161 and 157 untreated or vehcle-injected controls tht were necropsied. Incidences were not increased (P?0.05) for any turur ty in any sex-strain subroup or in the coined sexes of ei ther strain (NlIS, 1968) (The Working Group noted that a negative result obtained with a single s.c. injection may not be an adeate basis for discounting car- cinogenci ty ) . 3.2 Oter relevant biological data (a) Exrimtal system

The i.p. LD of scxium diethyldithiocarbate ln rnce iS abut 50 1 g!kg l: (Maj & Vetulan, 1970). ln a 6-week exrimt in rnce, daily s. c. injections of 50 rn!kg l: had maked anti -thyroid acti vi ty (Amru et aL., 1951).

220 ln rats, four metallites, diethyldithocarbate, diethyldithiocarba- rnte-S-glucuonide, inorganic sulphate and carbon disulphide were identified; these are also netalites of disulfiram (Strörr, 1965). Soium diethy ldi thiocarbate reduces bloo copper concentrations. Pregnant rabbits injected intravenously with 0.5 g sodum diethyldithiocarbate/day on 5 days per V-ek thoughout pregancy failed to deliver litters

(Howell, 1964).

A srl but signficant increase in the num of chrorrsorr breakages and abrrations was found in Vicia faba (Kihlm, 1957). (b) Ma Soium diethyldithocarbate has been used in the treatrnt of 13 cases of acute nickel carbony 1 poisoning and in one case of hepatolenti- cular degeneration (Wilson' s disease) (Sunder, 1964). 3. 3 Case reports and epidemological studies

No data were available to the Working Group.

4. Corrents on Data Reported and Evaluation 4 .1 Animl data Soium diethyldithiocbate has be tested by oral admnistration and by sing.le subtaneous injection in tw strains of rnce. Although it produced an increase in the incidence of li ver-cell tururs in males of one strain and a slight increase of lung tururs in m:les of the other strain followg its oral admistration, the available data are insufficient to rne an evaluation of the carcinogenicity of this cornund. 4. 2 Hur data

No case reports or epidemological studies were available to the Working Group.

221 5. References

Amrus, C.M., Amrus, J.L. & Harisson, J.W.E. (1951) Effect of sodum diethyldithocarbate on thyroid activity. Arr. J. PharcoL., 123, 129-130

Anon. (1975) Materials and Cornunding Ingredients for Rubær, Nc: York, Bill Communcations, p. 45

Canterford, D.R. & Buchanan, A.S. (1973) Application of differential pulse polarogaphy to anodic electrode processes invol ving mercu cornund formtion. Electroanalyt. Ch. Interfacial Electrochem., 44, 291-298

Canterford, D.R., Buchan, A.S. & Bond, A.M. (1973) Advantages of rapid direct curent polarography in the presence of anal yticall y undesirable phenora associated with anodc rnrcur waves. Anlyt. Cher., 45, 1327- 1331

Delepine, M. (1907) Meta1lic salts of dithiocarbarc acids; preparation of isothiocanates in the aliphatic series. C.R. Acad. Sci. (Paris), 144, 1125-1127 Halls, D.J., Townshend, A. & Zur, P. (1968) Polarogaphy of sorn su1phur- containing ccrunds. XIII. Anodic waves of dialkyldithocarbates. Analyt. chi. acta, 41, 51-62

Hawley, G.G., ed. (1971) Condensed Chercal Dictionary, 8th ed., NEW York, Van Nostrand-Reinhold, p. 799 van Hoof, F. & Heyndrickx, A. (1973) Thn layer chrorrtographic-spectro- photophuorirtric rnthods for the deterrnation of di tho- and thol- carbates after hydrol ysis and coupling wi th NBD-Cl. Ghnt. Ri jks- univ. Fac. Ladbl. Med., 38, 911-916 Howell, J .M. (1964) Effect of soum diethyldithiocarbate on bloo copper- levels and pregnancy in the rabit. Nature (Lond.), 201, 83-84

Innes, J.R.M., Ulland, B.M, Valerio, M.G., Petrucelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Fal, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for tUlrigenicity in mice: a prelirar note. J. nat. Cancer Inst., 42, 1101 - 1114 Kihlm, B.A. (1957) Exrimntally induced chromosome abrrations in plants. 1. The prouction of chromosor abrrations by cyanide and other heavy metal cornlexing agents. J. biophys. biochem. Cyol., 3, 363-380

222 Koch, H.P. (1949) Absorption spctra an strcture of organc sulphur co11unds. III. Vulcanisation accelerators and related counds. J. cher. Soc., 401-408

Kurzawa, Z. & Kubaszewski, E. (1974) Determnation of microgam amunts of sodium diethy ldi thiocarbate by ITans of iodine-azide reaction. Cher. analyt. (Warsaw), 19, 263-269

Maj, J. & Vetulani, J. (1970) So pharmcological properties of N, N- disubstituted dithiocarbates and their effect on the brain catechol- ame levels. Euop. J. Phacol., ~, 183-189

NTIS (National Techncal Informtion Service) (1968) Evluation of Cacino- genic, Teratogenic and Mutagenic Activities of Selected Pesticides and Industrial Chercals, Vol. l, Carcinogenic Study, Washington IX, US Depat of Corrrce Shaver, F.W. (1968) Ruber chercals. ln: Kik, R.E. & Oth, D.F., ed, Encyclopeia of Chemcal Technolog, 2nd ed., VoL. 17, NEW York, John Wiley & Sons, pp. 513-514 Stecher, P .G., ed. (1968) The Merck Index, 8th ed., Raay, ID, lvrck & Co., p. 958

Str&r, J.H. (1965) Metalisr of disulfiram and diethyldithiocarbarte in rats with demnstration of an in vivo ethanol-induced inibition of the glucuonic acid conjugation of the thiol. Biochem. Phacol., 14, 393-410

Sunderm, F. W. (1964 ) Nickel and copper mobilization by sodium diethyl- di thiocarba te. J. New Drugs, ~~y-June, 154- 16 1

Tisdale, W.H. & William, 1. (1934) Disinfectant. us Patent 1,972,961, Septemr 11, to E. 1. du Pont de Nemurs & Co. US International Trade Corrssion (1975) Synthetic Organic Chcals, US Production and Sales of Rubber-Procssing Chemcals, 1974 Prelirar, Washington DC, US Govert Printing Office, p. 7 US Tariff Corrssion (1941) Sythetic Organic Chcals, US Prouction an Sales, 1940, Report No. 148, Second Series, Washington De, us Governt Printing Office, p. 50 us Tariff Conrssion (1971) Sythetic Organc Chcals, US Production and Sales, 1969, TC Pulication No. 412, Washington IX, US C':iverrt Printing Office, pp. 144, 148-149

223 THlRA

1. Chercal and Physical Data

1.1 Synonyr and trade nars

Cher. Abstr. Reg. Serial No.: 137-26-8

Cher. Abstr. Nar: Tetrarthylthioperoxydicarbonic diamde

Bis ( (dirthylal1ino) carrxmothioy1J disulphide; bis (dithylthiocbayl) disulphide; bis (N.. N-diithy 1 thiocarbay 1) disulphide; bis (dithy 1 - thiocbal) disulphide; 1,11 -dithobis (N.. N-dimthylthioforrde) ; a, a-di thobis (diithy 1 thio) formde; a, a ' -di thiobis (dithy 1 - thio) formde; N.. NI - (di thiodicarbonothoy 1) bis (N-rnthy 1rthamne) ; rnthyl thram; rrthyl thiuranisulphide; tetrarthyldiurane: L sulphite; tetrarthylenethurar disulphide; tetrarthylthio- carbamy ldisulphide; tetrarthy 1 thiuram; tetrarthy 1 thiuram bisul- phide; tetrarthyl thiurar disulphide; N.. NI -tetramthylthiurar disulphide; N.. N.. N ' .. N ' -tetramthy 1 th urar disulphide; tetrarthy 1 - thiuran disulphide; tetrarthyl thiurane disulphide; tetrarthyl- thiur disulphide; tetrathuram disulphide; thurar; 'l'lll; 'IS

Accelerator Thiurar; Aceto TE; Arasan; Arasan 42-S; Arasan 70; Arasan 75; Arasan-M; Arasan-SP; Cyam DS; Ekgom TB; Fernasan; Fernasan A; Fernide; Herml; Herl; Kregasan; Mercurar; Methyl Tuads; Nobecuta; Norrrsan; Panoram 75; Polyrar Ultra; Ponarsol; Pornsol Forte; Ponasol; Pualin; Rezifilm; Roal 'I; Sadoplon; Spotrete; Tersan; Tetrasipton; Thllate; Thiosan; Thotox; Thirar B; Thirar 75; Thrasan; Thulin; Thiurad; Thuram D; Thiurar M; Thiurar M Ruber Accelerator; Thuraml; Thuirar; Thylate; Tiurarl; Tridipar; TriponDl; Tuds; Tux; Tuisan; VUAgt- l -4; Vulcafor 'I; Vulkaci t MlIC

225 1. 2 Chercal formula and rrlecar v.ight

CH 3 S S CH 3 ~N-C-S Il -S-C-N Il / CH/ 3 CH~ 3

C6H12N2S 4 t-b1. wt: 240.4 1. 3 Chemcal and physical proprties of the substance

From Weast (1975), unless oterwse spified

(a) Description: Wh te or yellow rrnoclinic crystals

(b) Boiling-point: l290C at 20 nm

(d) Spetroscopy data: Àni 243 nr (in chloroform) and 282 nr (E- = 478 and 524); for infra-red and nuclea magnetic resonce 1 spectral data, see Grasselli (1973)

(e) Solubility: Insoluble in water, alkalis and aliphatic hydre- carrons; slightly soluble in ethanol and ether (.(0.2%); soluble in acetone (1.2%), benzene (2.5%) and chloroform

(Stecher, 1968)

(f) Stability: Deorsed by acids (Association of Arrican Pesticide Control Officials, Inc., 1962)

1.4 Technical products and irurities Thiram poer is available corciall y ln the us wi th the following specifications: white ta crea ¡:er; density, 1.42:10.03; rnlting-range, l42-l560C; rristure, 1.0% rn.; ash, 0.5% rnx.; particle si7.e, 99.9% passes though a 100-rrsh scree; petroleum ether extract, 1. 0- 3 .0% (Ann., 1974) .

For ruber processing, thram is available as a fine pcder containing 1.5-2.5% (rn.) white oil, as extrded pellets containing 5.5% oil, as a dispersion containing 30-40% binder or oil, ln a mixture of two pats thram to one part 2-mecaptobenzothazole, and as pellets in a 50: 50

226 miture with disulfirar (Anon., 1975).

For use as a pesticide, thiram is available as 1.0-75.0% in dust; as 2.25-5.0% in granules; as Il.25, 35.2, and 42.0% in ligud ooncentrates; as 2.0% in paste; as 1.0% in paints for \\und dressing of shrus and trees; and as 3.0-98.0% in wettale pcers (US Environntal Protection Agency, 1974) .

Speifications for ths prcxuct ln Japan are: purity, 98%; appear- ance, yella: paer; melting-point, abve 1030C; water, less than 0.3%; unspecified inorganic imurities, 0.3%; and organic imurities (bis (di- rnthy ldi thocbay 1) sulphide and bis (petamthy lene thocarbay 1) tetra- sulphideJ, 1.0 to 1.4% (Japanese Miistr of Agriculture and Forestry, 1975).

2 . Prcxuction, Use, Occurence and Anal ysis

For imrtt background informtion on this section, see prearle, p. 15.

2.1 Prcxuction and use

Thiram was first prepaed by the oxidation of the dimthylarne salt of dimthyldithocbac acid wi th icxine in an etholic solution (von Braun, 1902). Although several other ræthod have been describd, thiram is believed to be prcxuced ccmrciall y in the US by passing chlorine gas though a solution of scxium dithyldithocabamte (Wenyon, 1972). ln Caada, it is prcxuce corrcially by the oxidation of scium dimthyl- di thocbate wi th hydrogen peoxide or icxine (Spencer, 1973). ln Japan, it is prcxuced carrcially fran iron oxide, hydrogen ¡:roxide, sodium hydroxide, dimthylarne and carbon disulphide (Japaese Miistr of Agriculture and Forestr, 1975).

Thiram was first prcxuced carrcially ln the US in 1925 (US Tariff Commssion, 1926); production was 2 million kg in 1960 (US Tariff Comms- sion, 1961) and 7.9 million kg in 1973 (US Interntional Trade Comssion, 1975a). ln 1974, four US comies reported the prcxuction of 5.8 million kg (US Interntional Trade Comssion, 1975b).

227 It is estimted that total anual production of thiram in Euope is from 5 to 10 million kg, produce in the Beelux countries, France, the Federal Republic of Germy, ltaly, Spain and the UK. ln Japan, corrcial production of thiram began in 1953. ln 1970, four coes reported the production of 140 thousand kg, and in 1974, 238 thousand kg (Japaese Ministr of Agriculture and Forestr, 1975). Abut 97% of the thiram utilized in the US is as prim and seconda accelerators in cornunding natural, isobutylene-isoprene, butadiene,

styrene-butadiene, synthe tic isoprene and nitrile-butadiene rubers. It renders law sulphur and sulphur- less stock heat-resistat, is non- discolouring and non-staining, and is an excellent acti vator for guandies, amnes and thiazoles. Thiram is also used as a cue retader in Neoprene G rubbers (Anon., 1975).

It is also used as a fungicide on seeds, fruts, nuts, vegetales and ornamtal crops, and on paper , polyuethane foa products and industrial textiles (US Environrtal Protection Agency, 1974). L t is used as an animl repellant, to protect trees and shrs fran rabbi t and dee depredtion (Berg, 1975). Thram rry have been used as a bacteriostat in soap (Klar, 1963) and antiseptic sprays (Stecher, 1968). Miscel- laneous applications include its use as an anti-oxidant in p::Üyolefin plastics (Dugan, 1963) and as a peptizing agent in polysulphide elast~rs (Saltm, 1965).

According to the US Occupational Safety and Heal th admistration heal th standards for air contats, an erloyee' s exsure ta thrar should not excee 5 IT/m 3 in the workplace air during any eight-hour workshift for a forty-hour work wee (US Coe of Federal Reations, 1975). Th rr allawle concentration proposed in the USSR is 0.5 IT/m:: (Winell, 1975).

ln the US, residue tolerances for thram when used as a fungicide were set at levels of up to 7 rrjkg for a variety of fruits and vegetales. Restrictions were also placed on the use of treated sees (US Environmtal Protection Agency, 1974).

228 ln Decerr 1974, the Joint Meting of the FAO Working Party of Exrts on Pesticide Residues and the WHO Ex Cottee on Pesticide Residues estalished a revised temrar acceptale daily intae for ma of 0-0.005 rng/kg bw for all dimthyldithiocarbate fungicides (WHO, 1975a,b). 2 . 2 Occurrence Thirar is not know to occur as a natural product. Residual arunts may rest on or in treated crops after haresting.

2.3 Analysis A rnthod for the qutitative deterrnation of thram in vegetales, based on gas-chromatogaphic anal ysis of the cabon disulphide evol ved was used for deterrnations in sarles containing 3.5 and 7.0 ir/kg (McLeod & Mcully, 1969). A microbiological rnthod using Saccharomyces car lsbergensis ATCC 9080 as the test organism has be developed for the deterrnation of thram in foo preparations; as li ttle as 25 ng/well or 200 ng/disc can be detected on agar plates (Rappe et al., 1973).

Gel perration and thn- layer chromatogaphic rnthods were used for the analysis of vulcanization accelerators, including thram, in exacts of synthetic rubers and mixtures of technical ruber addi ti ves (Proti vová et aL., 1974). A thin-layer chrorntogaphic-spectrophotofluorimtric rnthod for the estimtion of thiram allCJs detection of 40 ng (va Hoof & Heyndrickx, 1973).

3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma

3.1 Carcinogenicity and related studies in animls

(a) Oral admnistration

Mouse: Groups of 18 rnle and 18 ferle (C57BL/6xC3H/An)F rnce and 1 18 rnle and 18 femle (C57BL/6xA) F mice received cc:rcial thrar 1 (m. p. 154- L560C) according to the fOllCJing schedule: 10 m;/kg bN in gelatine at 7 days of age by stomach tub and the sai arunt (not adjusted for increasing boy weight) daily up to 4 weeks of age; subseqently, the mice were given 26 m; thrar per kg of diet. The dose given was the rn- rnum tolerated dose for infant and young mice but not necessaril y so for

229 adults. The exirt was termnated when the ans were alut 78 week of age, at whch tii 16, 18, 18 an 15 mice in th four groups, respti vel y, ~re still ali ve. Tuur incidences were cored wi th thse observed aing 79-90 necropsied mice of each sex an strain, which either had been untreated or had recived gelatine only: the incidences were not significantly greater (P:;0.05) for any turur typ in any sex-strain suboup or in the coined sexes of either strain (Innes et al., 1969; NTIS, 1968).

An unpecif ied ni.r of CS 7BL rnce were gi ven ~kl y doses of 300 TI'g/kg l: thram by stcxch tub for 5 wee and v.re killed at intervals of up to 9 Irnth after the last dose. Of 51 rnce killed at 9 rrnths, 2 had lung adens. The incidence in untreated controls is not given (Cherov et al., 1972) (The short duration of this exrirt should be notedJ. (b) Subtaeous admnistration

t-use: Groups of 18 mIe and 18 femle (C57BL/6xC3H/An)F nuce and 1 18 male and 18 femle (C57BL/6xA)F mice w=re given single s.c. injections 1 of 46.4 mg/kg l: thrar (rn.p. l54-1560C) in 0.5% gelatine on the 28th day of life and were observed until they were alut 78 w=eks of age, at which tii 16, 16, 17 an 16 mice in the four groups, respectively, were still ali ve. Tuur incidences were caed wi th those in groups of 141, 154, 161 an 157 untreated or vehcle-injected controls tbt were necropsied. Incidences were not increased (P:;0.05) for any tuur ty in any sex-strain subroup or in the corrined sexes of either strain (NTIS, 1968) (The Working Group noted tht a negative result obtained with a single s.c. injection may not be an adeqte bais for discounting carcinogenici ty J .

3. 2 Otr relevant biological data (a) Exirtal system The approximte oral ID values for thiram in nuce, rats and rabbits 50 are 1800, 820 and 210 rr/kg b., respectively (Kircheim, 1951; I., 1951). An oral LD of 2300 rr/kg b. has æe reported in virgin femle NM strain 50 mice (Matthaschk, 1973). Th derml ID in rats is rrre than 2000 rrg/kg b. 50 (Ben-Dyke et al., 1970).

230 No adverse effects were see in a 3-generation study in whch rats wee fed 48 rr tham per kg of diet. ln rats fed diets containing 100, 300 or 500 rr per kg of diet for 2 years, thre wee smll reductions in graw rates; aing thse fed the tw higher levels there was increaed mortlity; and in those at the highest dose there w=re convusions, thyroid hyprplasia (Griepentrog, 1962) and calcification of the cerebllur, hyp- thalam and rrulla oblongata (WHO, 1965).

Like most dithiocbartes, thrar inuces the accuration of acetaldehyde in tæ bloc of rats receiving ethanol at the sai tim (van IDen, 1972). Its reaction with nitrite at an acid pH in the stanchs of gua- pigs ~n vivo gi ves rise to N-nitrsothylae (Elespu & Lij in, 1973; Sen et al., 1974).

When pregnt NM mice ~re gi ven oral doses of 10-30 rr/anl from day 5-15 of pregancy, increased resorpion occued during interrate and late stages of foetogenesis. Malformtions, characterized by cleft palates, microtha, wavy ribs and distorted banes, were found in the developing foetuses and in the pups at terr (Matthaschk, 1973; Roll, 1971). Sirultaeous admistration of thram and 10 mg/animl L-cysteine intraperitoneally from day S-15 of pregncy resulted in a signficat decrease bath in the severity and in the nurr of emryopathes (Matthaschk, 1973). Thrar inuced charsorr abrrations in baley (Gerge et al., 1970), but no increase in the nurr of chlorophyll nutations was found in wheat (Malyga et aZ., 1974). An increased nt.lmber of chorrsornl abrrations was observed in rntaphases of bone-mrrON cells of mice treated with 100 mgl kg l: orally (Antonovich et aZ., 1971).

(b) Ma

Doses of 0.5 g/day have l:en taen for several wes without adverse effects, provided tht no ethanol was consum (Dago, 1952). For a discussion of the interaction of cornunds such as thirar wi th ethanol in the bloo, see 'General Remks on Carbates, Thiocarbamtes and Carbazides' , pp. 28-29.

231 3. 3 Case reports and epidemological studies

ln a group of 223 workers (42 ne and 181 \'ræ), nostly aged between 20-50 yeas, engaged in the rrufacture of thiram for nore than 3 years and observed for several years subseqentl y, various clinical and pathological maifestations, including oclar irritation, coughing, thoracic pain, tachicardia, epistais, derrl lesions, ITocardiodystrophia, clinical and sublinical 1i ver dysfunction and asthenia w=re reported, often in excess of those seen in a group of 193 persons Ilt in contact wi th thiram. Enlarge- ment of the thyroid gland was rrre cornn in the exsed groupa One case of adenocarcinoma of the thyroid and 7 others wi th thyroid abnorrli ties were reported arng ios workers exarned (Cher et aZ., 1971; Kaskevich & Bezugly, 1973).

4. Cornts on Data Reported and Evaluation 4 . 1 Animl data

Thiram has ben tested by oral adnistration and by single subtaneous injection in mice. Although no cacinogenic effect was observed in these studies, the available data are insufficient for an evaluation of the carcinogenici ty of this colTund to be rrde.

Thiram can react with nitrite under mi1dly acid conditions, sirlating those in the hum stomach, to forr N-nitrosodithy1arne, which has been shown to be carcinogenic in seven animl species (lAC, 1972). 4 . 2 Hur data

The one case of thyroid cacer reported forr an insufficient basis on which to evaluate the carcinogenicity of thiram in ma.

232 5. References

Anon. (1974) Methyl Tuds(È , New York, R.T. Vanderbilt Co.

Anon. (1975) Materialc and Corrunding Ingredients for Ruber, New York, Bill Conmunications, pp. 31-59

Antonovich, E.A., Chepynoga, O.P., Chernov, O.V., Rjazanova, P.A., Vekshtein, M.S., Mason, V.S., Matson, L.V., Sash, L.V., Pilinskaya, M.A., Kuriny, L.I., Balin, P.N., Khitsenko, 1.1., Zastavnjuk, N.P. & Zaolorozhnaja, N.A. (1971) Toxicity of dithiocarbantes and their fate in warlooed animls. ln: Antonovich, E.A., Bojanovska, A., Engst, P. et al., ed, Proceeings of the Symsium on Toxicolog and Anlytical Chemstr of Dithocarbates, Dubrovnic, 1970, Bead, pp. 3-20 Association of Amrican Pesticide Control Officials, Inc. (1962) Pesticide Chemcals Official Compndium, Box RH, University P.O., College Park, Marylan, p. 307

Ben-Dyke, R., Sanderson, D.M. & Noes, D.N. (1970) Acute toxicity data for pesticides. wid Rev. Pest. Control, 9, 119-127 Berg, G.L., ed. (1975) Farm Checals Handbk 1975, Willoughby, Ohio, ~eister, p. D 203 von Braun, J. (1902) Thiurarisulfides and iso-thurarsulfides. 1. Chem. Ber., 35, 817-829

Chernov, O.V., Khitsenko, 1.1. & Bain, P.N. (1972) Blastorenic properties of sorr deri vati ves of di thiocarbac acid and their netali tes. Onologiya, 2, 123-126

Cherp, V.V., Bezugly, V.P. & Kaskevich, L.M. (1971) Sanitary-hygienic characteristics of working conditions and heal th of persons working with tetrarthylthuram disulfide ('I). Vrach. Delo, 10, 136-139

Domingo, A.F. (1952) Ensayos de taxicidad con naiz tratados con 'Arasan' y 'Spegon'. Rev. Me. Veta (Caracas), 11, 335-348

Dugan, L.R. (1963) Antioxidants. ln: Kirk, R.E. & Otr, D.F., eds, EnC\.lclopeia of Chercal Technolog, 2nd ed., VoL. 2, Ne York, John Wiley & Sons, pp. 600-604 Elespur, R.K. & Lijinsky, W. (1973) Th fonrtion of carcinogenic nitroso cornunds from ni tri te and sone typs of agricul tural chemcals. Fd Cosmt. Toxicol., 11, 807-817

George, M.K., Aulak, K.S. & Dhesi, J .S. (1970) MJrphological and cytological changes induced in baley (Hordeum vulgare) seedlings follCMing seed treabTt with fungicides. Caad. J. Geet. Cytol., 12, 415-419

233 Grasselli, J .G., ed. (1973) Atlas of Spectral Data an Physical Constats for Organc Cornunds, Cleveland, Ohio, Chemcal Ruber Co., p. B-484

Griepetrog, F. (1962) Turarige Schilddrsenveränderugen in chronisch- toxikologischen Tierversuchen mit Thiurain. Beitr. Path. Ant., 126, 243-255 van Hoof, F. & Heyndrickx, A. (1973) Thn layer chromatographic-spctro- photo uorimtric rrthods for the deterrnation of ditho- and thiolcarbates after hydrolysis and coupling with :ND-Cl. Ghent. Rijks- univ. Fac. Ladbl. Med., 38, 911-916 lAC (1972) lAC Monographs on the Evaluation of Cacinogenic Risk of Chemcals to Ma, l, Lyon, pp. 95-106

Innes, J.R.M., Ullan, B.M., Valerio, M.G., Petrcelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gat, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for tUlrigenicity in mice: a prelirnar note. J. nat. Cancer Inst., 42, 1101-1114

Japaese Ministr of Agriculture and Forestr (1975) Noyaku Yoran (Agri- cultural Chemcals Anual), 1975, Division of Plant Disease Prevention, Tokyo, Takeo Endo, pp. 17-20, 22, 26, 86, 89, 101, 254, 267-269, 271, 275, 301

Kaskevich, L. M. & Bezug 1 y, V. P . (1973) Clinical aspects of intoxications induced by 'I. Vrach. Delo, 6, 128-130

Kirchheim, D. (1951) Toxizität und Wirkug einiger Thiurarisulfid-verbindungen auf den Alkoholstoffwechsel. Naunyn-Schnedebrg' s Arch. ex. Path. Pharol., 214, 59-66 Klarm, E.G. (1963) Antiseptics and disinfectats. ln: Kirk, R.E. & Otr, D. F ., eds, Ency lopeia of Chemcal Technolog, 2nd ed., VoL. 2, New York, John Wiley & SOns, pp. 636-637 I., A.J. (1951) Chca1s in foo: a repot of the association of foo and drg officials on curent develo¡:nts. II. Pesticides. Qurt. Bull. Ass. Fd Drug Off. US, 15, 122-133 van Loten, M.J. (1972) De Dithiocarbaat-Alcohol-Reactie bij de Rat, Teroorg, The Nether lands, Bedri j f FA. Lars, p. 38

Malyga, V.S., Kulik, M.1. & I.inenko, V.F. (1974) Induced chlorophyll mutations in hard spring wheat. Dokl. Akd. Nauk SSSR, 215, 211-213

Matthiaschk, G. (1973) übr den Einfluss von L-cystein auf die Teratogenese durch Thiram ('I) bei NMI-l"usn. Arch. Toxiol., 30, 251-262 Mc, H.A. & M:ully, K.A. (1969) Head space gas procedure for screening foo sarles for dithocarbate pesticide residues. J. Ass. off. analyt. Cher., 52, 1226-1230 234 NTIS (National Technical Informtion Service) (1968) Evluation of Carcino- genic, Teratogenic an Mutagenic Activities of Selecte Pesticides and Industrial Chemcals, Vol. l, Carcinoenic Study, Washington OC, US Depant of CoITrce Protivova, J., Pospisil, J. & Holcik, J. (1974) Antioxidats an stailizers. XLVIII. Analysis of the conents of stalization and vucaization mixtures for rubers by gel terration an thn- layer chromatogaphic rnthods. J. Chromat., 92, 361-370

Rappe, A., Maugoy, G. & Bauer, S. (1973) Microbiological deterration of thiram. J. Ass. off. anlyt. Ch., 56, 1517-1518

Reinl, W. (1966) Aloholübrerfindlichkeit nach l:ang mit dem Fugicid Tetramthylthuranisulfid ('I). Arch. Toxiol., 22, 12-15 Roll, R. (1971) Teratologische Untersuchungen mit Thram ('I) an zwei Mäusestfn. Arch. Toxikol., 27, 173-186 Saltm, W.M. (1965) Elastcmrs, sythetic. ln: Kik, R.E. & Othr, D.F., eds, Encyclopeia of Chcal Technolog, 2nd ed., VoL. 7, New York, John Wiley & Sons, pp. 696-697

Sen, N.P., Donaldson, B.A. & Chrbnneau, C. (1974) Formtion of nitrosodimthy lame from the interaction of certain pesticides and ni tri tes. ln: Boovski, P. & Walker, E.A., eds, N-Nitroso Ccunds in the Environrnt, Lyon, IA (!A Scientific Pulicatìons No. 9) 1 --- pp. 75-79 Specer, E. Y. (1973) Guide to the Chemcals Used in Crop Protection, 6th ed., London, Ontario, University of Western Ontario, Reseah Branh, Agriculture Canada, Pulication 1093

Stecher, P.G., ed. (1968) The Meck Index, 8th ed., Raay, NJ, M2rck & Co., p. 1047 us Code of Federal Reglations (1975) Air Contaants, Ti tle 29, part. 1910.1000, Washington IX, US Governt Printing Office, p. 61 US Envirorital Protection Agency (1974) EPA Ccmdiur of Reistered Pesticides, VoL. II, Fungicides and NEnticides, Washington IX, US Governnt Printing Office, pp. I-T-30-00.0l-I-T-30-00.09 US International Trade Corssion (1975a) Synthetic Organc Chcals, US Production and Sales, 1973, IT Publication 728, Washington IX, US Governnt Printing Office, pp. 137, 141 US International Trade Conrssion (1975b) Sythetic Organc Chercals, US Production and Sales of Rur-Processing Chcals, 1974 Prelirnary, Washington DC, US Goverrt Printing Office, pp. 4, 8

235 US Tariff Commssion (1926) Census of Oyes and Oter Synthe tic Organc Chercals, 1925, Tariff InoD'tion Seies"NJ. 34, Washington OC, US Governt Printing Office, p. 148

US Tariff Comsiop (1961) Synthe tic Organic Chcals, US PrOduction and Sales, 1960, TC Pulication 34, 'V7ashington IX, US Governnt Printing Office, p. 43

Weast, R.C., ed. (1975) CRC Handbk of Chstr and Physics, 56th ed., Cleveland, Ohio, Chemcal Ruber Co., p. C-272 Wenyon, C.E. (1972) Organic sulfur counds. ln: Chemcal Technolog: An Encyclopeic Treatmnt, VoL. 4, Petroleur and Organic Chercals, New York, Eaes & Noble, pp. 621-623 WH (1965) Evaluation of the toxicity of pesticide residues in foo. WHO/Foo Add.j27. 65, pp. 181-184

WHO (1975a) Pesticide residues in foo. Report of the 1974 Joint Meting of the FAO Working Pary of Exrts on Pesticide Residues and the WHO Exrt Comnttee on Pesticide Residues. Wld Hlth Org. techn. Rep. Ser., No. 574, pp. 26-30

WHO (1975b) 1974 Evaluations of so pesticide residues in fcx. Wld Hlth Org. Pest. Res. Ser., No. 4, pp. 537-545 Winell, M.A. (1975) An international corrarison of hygienic stadards for chemcals in the work environmt. Amio, 4, 34- 36

236 ZECI'Rz\l\

1 . Chemcal and Physical Data 1 .1 Synonyr and trade nas

Cher. Abstr. Reg. Serial No.: 315-18-4 Cher. Abstr. Nam: 4- (Dimthy lamno) -3 , 5-dimthy lphenol rnthy 1- carbate (ester)

4- (Dimthy lamno) - 3, 5-dithy lphenol, rnthy lcarbate i 4-dithy 1 - amno- 3, 5-dimthy lpheny 1 N-rnthy lcarbate ¡ 4- (dithy lamo) - 3,5- xylenol, rnthylcarbate (ester) ¡ 4-dimthylamno-3,5-xylyl rnthylcarbate ¡ 4-diethy lama- 3, 5-xy 1 yI N-rnthy lcarbate ¡ nethy 1 - carbac acid, 4- (dimthy larno) - 3, 5-xy ly 1 ester ¡ rnthy 1 -4-dirthy 1 - amo-3,5-xylyl carbate¡ rnthyl-4-dimthylarno-3,5-xylyl ester of carbac acid

Dowco l39¡ EN 25,766¡ Mexacarbate¡ Hexicarbate¡ Zactran¡ Zectane ¡ Zextran 1. 2 Chercal formla and rrlecular ~ight o Il /H

rh C-N'cH, H,c¥CH, / N\ CH3 CH3 C12H18N202 !-l. wt: 222 . 3 1. 3 Chemcal and physical properties of the substance

From Stecher (1968), unless otherwise speified

(a) Description: Crystals

(b) ~lting-point: 850C

237 (c) Solubility: 0.01% soiiile in vlêiter at 2SoC; soluble ln acetone, acetonitrile, ethanol, benzene and nethylene chloride

(d) Volatility: Vapour pressure is .(0.1 mu at l390C.

(e) Staility: Hydrolyses rapidly in alkaline solution; subject to photo-decompsition in the solid state (Hosler, 1974)

1.4 Technical products and imuri ties Zectran is no longer produced in the US but was fonærly available as an emulsifiable concentrate containing 22.3% of the pure chemcal, as a wettable :¡der containing 25% of the comund and as a bait fonnulation (Spencer, 1973).

2. Proouction, Use, Occurrence and Analysis

For imrtant background inforntion on ths section, see prearle, p. 15. 2. 1 Proouction and use

Zectran can be prepared by reductive alkylation of 4-nitroso-3,S- xylenol, followed by reaction with irthyl isocanate (Shulgin, 1962; Spencer, 1973).

It was produced on a pilot plant sc ale by one US compy from 1961 until 1974 (Anon., 1975; Berg, 1976), but there is no evidence that the qutity produced exceeed a few thousand kg anually.

It is registered in the US for use as an insecticide and as a rrl- luscicide for the control of may pests of lawns, turf and flowers (US Environrtal Protection Agency, 1974) but not for use on foo crops. ln 1975, 15 thousand kg were applied in an errgency neasure to control an outbreak of spruce budwonn in the state of l'mne (Anon., 1975).

2 . 2 Occurrence Zectran is not know to occu as a natural product.

238 2. 3 Anal ysis

A general ræthod for the anlysis of organic lXllutants in water and waste water has been applied to zectran (Lichtenbrg, 1975). Chromatogaphic rnthods for the anlysis of carbates, including zectran, have been reviewed (Fishbin & Zielinski, 1967; Sherm, 1973).

Gas chromatography and a nitrogen- or sulphur-responsive alkali flam detector were used to anlyse plant extractsfor zectran (Lorah & Herhill, 1974). Electron-capture gas chrorntography has been used after derivatization with pentafluoropropionic anydride (Shern & Shafik, 1975). Zectran was separated from several other pesticides by thn- layer chomatography; the lirt of sensitivity was 0.2 ll9 (Ebing, 1972). A nethod involving fluorigenic lablling, thin- layer chromtogaphy and in si tu fluorimtr is capable of detecting 15 ng zectran on a routine basis; the lirt of detection was 1 ng

(Frei & Lawrence, 1972).

A water rrni toring system for cholinesterase inibi tors, including, but not specific for, zectran, uses an electrochercal cell which ræasures changes in the activity of imbilized enzyrs (Goson & Jacobs, 1972).

3. Biological Data Relevant to the Evaluation of Carcinogenic Risk to l'1a

3.1 Carcinogenicity and related studies in anirls

(a) Oral admistration

!-use: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F Mee and 18 male and 18 ferle (C57BL/6xA)F Mce received commcial zectran1 1 (95% pure) according to the followng schedule: 4.64 rn/kg br in gelatine at 7 days of age by stomach tub and the sar arunt (not adjusted for increasing boy weight) daly up to 4 wees of age; subseqntly, the mice were given 11 mg zectran per kg of diet. The dose was the maimum tolerated dose for infant and young mice but not necessarily sa for adults. The exprimnt was terrnated when the anirls were alut 78 weeks of age, a t which tim 14, 17, 17 and 16 mice in th four groups, respecti ve1 y, wee still ali ve. Tuur incidences were compared wi th those observed

239 arng 79-90 necropsied rnce of each sex and strain, which ei ther had been untreated or had received gelatine only: the incidences W2re increased in males of the first strain (9/16' versus 22/79) (P~0.05J but not in fenles of the sai strain nor in ei ther sex of the second strain. The incidence of lung adenomas was increased in toth sexes of the first strain (4/16 in males and 3/17 in fenles versus 5/79 and 3/87 controls; if toth sexes are considered together, P~O. 01). Heoatars W2re found in 5/16 males of the first strain, cornared with 8/79 in controls (P~0.05J, and in 2/17 males of the second strain, corned with 5/90 in controls (P:;0.05J. No hepatomas were seen in fenles (Innes et al., 1969; NlIS, 1968).

(b) Subutaeous admnistration

!-use: Grouos of 18 male and 18 ferle (C57BL/6xC3H/Anf)F rnce and 18 male and 18 ferle (C57BL/6xA)F mice were given single s.c.1 injections 1 of 10 rn/kg tw comærcial zectran (95% pure) in dithyl sulphoxide on the 28th day of life and were observed until they were alut 78 weeks of age, at which tir 17, 18, 17 and 17 mice jn the four groups, respecti vel y, were still alive. Tuur incidences were coIlared with those in groups of 141, 154, 161 and 157 untreated or vehcle-injected controls that were necropsied. Incidences were not increased (P:;O. 05) for any tumur ty in any se-strain subroup or in the comined sexes of either strain (NTIS, 1968) (The Working Group noted that a negative result obtained with a single s.c. injection may not be an adeqate basis for discounting cacinogenici ty J . 3.2 Oter relevant biological data

(a) Exrimntal system

The oral and dernl ID 's of zectran in rats are 14-63 and 1500-2500 50 rn/kg bw, respectively (Ben-Dyke et aL., 1970). A single :rrcutaneous application of 2000 mg/kg tw prcXuced no discernible effects in NEW Zealand rabbits (Tucker & Crabtree, 1969). Zectran inhibits acetylcholinesterase activity (Kuh & Dorough, 1976).

Meikle (1973) has provided a concise review of zectran rntablism. ln dogs, an oral dose of zectran was elirnated quantitatively in the urine as 4-diIthylarno-3,5-xylenol, predorantly in the conjugated forr, as conjugated forr of the 2,6-dimthyl hydroqinone, and as smll arunts of 2,6-

240 dimthyl-para-benzoqinone (William et al., 1964).

Dog and rat liver horrenates, dog kidney horrenates (Wheeler & Strother, 1971) and rat-liver microsorns (Oonnithan & Casida, 1966) netallized zectran into a miture of metablites, including 4-dirthylarno-3,5-xylyl-N-hydroxy- rnthylcarbate, 4-methylformdo-3,5-xylyl nethylcarbate, 4-methylarno- 3,5-xylyl methylcarbate and 4-arno-3, 5-xylyl rnthylcarbate. 4-Dimthyl- arno-3,5-xylyl-N-hydroxyethylcarbate was formd (6%) in a rat-liver preparation but not in a hum-liver preparation (Bedford, 1975). It caused an increase in the num of reverse mutations in Baci L lus subtilis (De Giovan-Donnelly et aL., 1968); rntabolic activation was not used in this test.

(b) Ma

ln an incident of acute zectran i:isoning, the bloo acetylcholinesterase level was lowered but retured to norml after 3 days (Richardson & Batteese, 1973). 3. 3 Case reports and epidemological studies

No data were available to the Working GraUD.

4. Corrnts on Data ReDOrted,- and Evaluation 4 . 1 Animl data

Zectran has been tested by oral adistration and by single subcutaneous injection in two strains of mice. Following its oral admnistration, an increased incidence of lung adenomas was observed in bath sexes of one strain cornined, together wi th a slight increase in the numr of li ver-cell tuiurs in males of the sa strain. The available data do not allow an evaluation of the carcinogenicity of zectran to be made. 4.2 Hum data

No case reports or epiderological studies were available to the Working Group.

241 5. References

Anon. (1975) Forest pests pestered. Chcal Wee, June 25, p. 18 Beford, C. (1975) Biotransforntions: agricultural and industrial chercals. ln: Hathay, D.E., ed., Foreign Comund Metallism in Mals, London, The Chercal Society

Ben-Dyke, R., Sanderson, D.M. & Noes, D.N. (1970) Acute toxicity data for pesticides. Wld Rev. Pest. Control, 9, 119-127 Berg, G.L., ed. (1976) FarChercals Handbk 1975, Willoughby, Ohio, Meister, p. D 273

De Giovani-Donnelly, R., Kolbye, S.M. & Greeves, P.D. (1968) The effects of IPC, CIPC, sevin and zectran on Baci iius subti lis. Exrientia, 24, 80-81 Ebing, W. (1972) Routinerthode zur Düschichtchromatographischen Identi- fizierug der Pestizidrckstade aus den Klassen der T~iazine, Carbate, Hastaffe und Uracile. J. Chromt., 65, 533-545 Fishbin, L. & Zielinski, W.L., Jr, (1967) Chortography of carbates. Chromat. Rev., 9, 37-101

Frei, R.W. & Lawrence, J.F. (1972) Determnation of rntacil and zectran by fluorigenic labling, thin layer chrortography, and &n si tu fluori- rntr. J. Ass. off. analyt. Ch., 55, 1259-1264

C~son, L.H. & Jacobs, W.B. (1972) RaD id Detection System for Organo- phosphates and Cabate Insecticides in Water, EPA-R2-72-0l0, Washington IX, us Environrtal Protection Agency

Hosler, C.F., Jr (1974) Degradation of zectran in alkaline water. BulL. environr. Conta. ToxicoL., 12, 599-605

Kuh, R.J. & Corough, H.W. (1976) Carbate Insecticides: Cherstr, Biocherstry an Toxicolog, Cleveland, Ohio, ChEmcal Ruber Co. , pp. 44-47 Lichtenbrg, J. J . (1975) Methods for the determnation of spcifie organic pollutants in water and waste water. Inst. Electrical Electronics Engineers Tran. Nuclear Sci.i NS-22, 874-891

242 Lorah, E.J. & Herhill, D.D. (1974) Direct chrorntography of sorn N-nethylcarbate pesticides. J. Ass. off. analyt. Chem., 57, 570-575

Meikle, R.W. (1973) Metalisr of 4-di1thylamno-3,5-xylyl nethylcarbate (rnxacarbate, active ingredient of zectran insecticide): a unified picture. Bull. environm. Contar. Toxicol., 10, 29-36

NTIS (National Technical Informtion Service) (1968) Evluation of Cacino- genic, Teratogenic and Mutagenic Activities of Selected Pesticides and Industrial Chemcals, Vol. l, Cacinogenic Study,. Washington IX, US Departrnt of Comærce

Cbnnithan, E.S. & Casida, J .E. (1966) Metallites of rnthy1- and di1thyl- carbate insecticide chemcals as form by rat liver microsomes. Bull. environm. Contar. Toxicol., l, 59-69

Richardson, E.M. & Batteese, R.1., Jr (1973) An incident of zectran poisoning. J. Maine rn. Ass., 64, 158-159 Shern, J. (1973) Chomtographic analysis of pesticide residues. CRC Crit. Rev. analyt. Chem., 3, 299-354

Sherr, J. & Shafik, T.M. (1975) A rnlticlass, mutiresidue analytical rnthod for deterrning pesticide residues in air. Arch. environm. Contar. Toxicol., 3, 55-71

Shulgin, A.T. (1962) p-Arophenyl carbates. US Patent 3,060,225, October 23, to Do Chercal Co.

Specer, E.Y. (1973) Guide to the Chemcals Used in CrOD Protection, 6th ed., Londn, Ontaio, University of Hestern Ontaio, Research Branch, Agricuture Canada, Pulication 1093, p. 354 Stecher, P .G., ed. (1968) The Merck Index, 8th ed., Raway, NJ, Merck & Co., pp. 1126-1127

Tucker, R.K. & Crabtree, D.G. (1969) Toxicity of zectran insecticide to several' wildlife species. J. econ. Entomol., 62, 1307-1310

us Environrtal Protection Agency (1974) EPA Cc:ndium of Reistered Pesticides, Washington IX, US Governt Printing Office, p. III-D-37.1 h'heeler, L. & Strother, A. (1971) In vi tpo metablisr of the N-rnthylcar- bartes, zectran and rnsurol, by li ver, kidney and bloo of dogs and rats. J. Pharmcol. ex. Ther., 178, 371-382 hTilliar, E., Meik1e, R. W . & Reder, C . T . (1964 ) Identification of rnta- boli tes of zectran insecticide in dog urine. J. agric. Fd Chem., 12, 457-461

243 ZINE

1. Chercal and Physical Data 1 .1 Synonyr and trade nas

Cher. Abstr. Reg. Serial No.: 12122-67-7 Cher. Abstr. Nar: Ul,2-Ethanediylbis(carbamithioato)) (2-) )zinc t (l, 2-Etediylbis (carbathioato)) (2-) )-S ,S'-zinc; l, 2-ethedi y lbiscarbai thioic acid, zinc complex ¡ l, 2-ethane- diylbiscarbamthioic acid, zinc salt¡ (ethylenebis (dithiocarbarte) )- zinc¡ ethylenebis (dithiocarbarto) zinc¡ zinc ethylene bisdithio- carbarte Aspor¡ Asporu¡ Bercer; Blizene; Cabadine; Cher Zineb; Cineb¡ Cri ttox; CynkotoX¡ Daisen; Dithane 65; Dithane Z; Dithane Z 78; Hexathane; Kupratsin; Kypzin; Lirotan; Lonacol¡ Micide¡ Miltox¡ Novosir N; Novozin N 50 ¡ Novozir; Novozir N; Novozir N 50; Pamsol 2 Forte; Parzate¡ Parzate C¡ Parzate zineb¡ Perosin¡ Perosin 75B; Perozin¡ Perozine¡ Polyrar Z; Tiezene¡ Tritoftorol¡ Zebnide¡ Zebtox¡ Zidan¡ Zineb 80 ¡ Zinosan 1 . 2 Chercal formla and molecular weight

HN-CH2-CH2-NH C1/5, Zn ..\", C ~ S./ "'S ./

C 4H6N2S 4 Zn l'1oL. wt: 275.8 1.3 Chemcal and physical properties of the substace

From Stecher (1968), unless otherwise soecified

(a) Description: Pawder or crystals (b) Solubility: Insoluble in water at room temrature¡ soluble in chloroforr, carbon disulDhide and pyridine

245 (c) Staility: Deomses æfore nelting (S:çncer, 1973) 1 . 4 Technical products and imuri ties

Zineb is available in the US as dusts containing 3.25-19.5 % of the chemcal, as wettale paders contaning 1. 4 to 75 % of the chemcal and as a 39% aqueous suspension (US Environmntal Protection Agency, 1974). Technical zineb is available in Japa in grades containing 90%, 93% or 95% of the chemcal (Japaese Miistr of Agriculture & Forestr, 1975). May commrcial samles of ethylenebisdithiocarbates, including zineb, have been shaw to contain ethylenethiourea (ET) (Bontoyan et al., 1972). Bontoyan & Loker (1973) studied the initial ET contents of o various such products and the levels found after storage at 88 C. The initial content in specific formlations of 'Zineb 80%' vaied between 0.16 and 2%; after 39 days of storage the levels were between 3.5 and 10.5%.

2. Production, Use, Occurrence and Analysis

For imrtant background informtion on this section, see preamle, p. 15.

2 . 1 Production and use

Zineb is believed ta have been first prepaed in 1941 (Hester, 1943). The rnthod thought to be used for i ts commrcial production is reaction of ethy lene diamne wi th carbon disulphide in the presence of alkali, followd by addition of zinc sulphate to precipitate zineb. This final step can also be carried out in a spray tank by the socalled 'ta-mix' of sodium or annium ethylenebisdithocarbate with zinc sulphate (US Environmtal Protection Agency, 1974).

Since only two conies curently prcxuce zineb in the US, separa te production data are not available; hawever, in 1974 production of a group of at least 9 dithiocarbate fungicides, including zineb, was 16 million kg (US International Trade Conrssion, 1975). Th highest reported production of zineb in the US was 3.8 million kg in 1961; 1.4 million kg were produced in 1968, the last year in which production was reported sepaatel y .

246 Most of the 1. 7 million kg of soum ethylenebisdithocarbarte produced in 1961 and the 0.9 million kg made in 1968 was probably converted to zineb by the ta-mix procedure (US Tariff Ccmssion, 1962, 1969). Total US exprts of all dithocbates, including zineb, in 1974 were 6.7 million kg (US DeparTInt of Agriculture, 1975).

It is estirted that the anual production of zineb in ltaly is 10-20 million kg, 5 million kg of which is us within the countr. Anual prouction in Spain is 1-5 million kg and that in France, 1ess than 1 million kg. It is also produced in the Federal Republic of Gey and The Netherlands (Berg, 1976). Production of zineb in Japan bean ln 1952; t\o compies produced 2 million kg in 1974. ln that year, 235 thousand kg of forrlated zineb were ÌIrted into Japa from France, Israel and the US. ln ealier years, minor quanti ties of zineb formulations were exprted from Japan to countries in south-east Asia, but none 'Mre reported in 1973 or 1974 (Japanese Ministr of Agriculture & Forestry, 1975).

Zineb is a fungicide and is registered for use in the US on over 50 fruit, vegetale and field crops, as \'.ell as on a large numr of orna- rnntal plants and for the treatmnt of rny seeds. Residue tolerances are estalished at 7 rn!kg for most raw agricul tural crop products. zineb is also registered for use as a fungicide in paints and for rruld control on fabrics, leather, linen, painted surfaces, surfaces ta be painted and paper, plastic and wo surfaces (US Environmtal Protection Agency, 1974).

ln Japan, over half of the 1. 8 million kg used in 1974 was on citrus fruts; most of the balance was used on vegeta1es, and a srnll anunt was used on flowers (Japanese Miistry of Agriculture & Forestr, 1975).

ln Deerr 1974, the Joint Meting of the FAO Working Party of Exrts on Pesticide Residues and the WHO Exprt Comm ttee on Pesticide Residues established a revised temrar acceptable dai1y intake for ma of 0-0.005 rn!kg bw for all dithiocarbate fungicides (WHO, 1975a,b).

247 2. 2 Occurrence

Zineb is not known to occur as a natural product. As par of the 'Total Diet Program' of the US Foo and Drug Adr- stration, 360 comsite foo samles were collected anually during the period 1964-1970, prepared as for consumtion and analysed for dithiocarbate content. A maum of 4 coITsi tes contained detectable levels of dithiocarbartes in any single year (Corneliussen, 1972), and in at least one year no dithocarbate was detected. On the basis of these results, analysis for dithiocarbamates in this p~ogram was discontinued after 1970 (Maske & Corneliussen, 1974).

The significance of zineb as a residue on agricultural products is enhanced by reports that the coking of foos containing ethylenebisdithocarbate residues would result in degradation to forr EI. Studies indicate that norml cooking of vegetables containing residues of zineb near the tolerance level v.uld resul t in the forrtion and possible hum consumtion of ET (Blasquez, 1973; v7atts et al., 1974). For inforrtion on the levels of EI tht rny be found on raw agricul tural products, see IAC (1974). 2. 3 Anal ysis

Two reviews have described ~thods of analysis for zineb (Fishbin, 1975; Fishbin & Zielinski, 1967). Gas chrorntography has been used to deterre zineb in foo and fees (Bighi, 1964); another gas chromtographic rnthod depends on the anal ysis of ethy lenediarne, which is forrd as a hydrolysis product of ethylenebisdithiocarbamte pesticides (Newso~, 1974) .

Stevenson (1972) has describd a test based on the colour developed by acid di thizone, which depends on the ty and concentration of rrtal present. Hcwever, the presence of a dithiocarbamte rnst be estalished separately, using conventional procedures. Polarogaphic nethods have also been used (Budnikov et al., 1974; Supin et al., 1973).

248 3. Biological Data Relevant to the Evluation of Carcinogenic Risk to Ma

3.1 Carcinogenici ty and related studies in anirls

(a) Oral admnistration

Mouse: Groups of 18 male and 18 ferle (C57BL/6xC3H/An)F rnce and 1 18 male and 18 femle (C57BL/6xA)F mice received commrcial zineb (97% 1 pure) according to the follcwing schedule: 464 m~/kg hv in gelatine at 7 days of age by stanch tub and the sa arunt (Ilt adjusted for increasing boy weight) daily up to 4 v;eks of age; suseqently, the mice were given 1298 mg zineb per kg of diet. Th dose given was the maimum tolerated dose for infant and young mice but not necessarily sa for adul ts. The exr.lt was terrated when the animls were aOut 78 weeks of age, at whch tim 15, 18, 16 and 16 mice in the four groups, respecti vel y, were still ali ve . Tuur incidences were cornred wi th those obsered arng 79-90 necropsied mice of each sex and strain, which either had been untreated or had received gelatine only: the incidences were not significantly greater (P?0.05) for any turur typ in any se- strain subroup or in the cornined sexes of ei ther strain (Innes et al., 1969; NTIS, 1968).

Of 101 strain A mice and 79 C57BL mice given ~ekly oral doses of 3500 mg!kg b, zineb (purity unspecified) in l% stach solution for 6 week and killed 3 month after the begining of the exr.lt, 35/101 (35%) and 6/79 (8%) developed lung adenor. Arng controls, 30/97 (31%) strain A mice and 0/87 C57BL mice develope lung adenomas (for C57BL mice, P=O. 01J. Of 29 C57BL mice given 11 weekly doses of 1750 rr!kg hv by stomach tub and killed 6 month after the beining of the exr.lt, 2 (7%) developed lung adenor, comped with 0/59 controls (Chernov & Khtsenko, 1969).

Rat: A group of 60 random-bred rats was given twice wekly doses of 285 mg!kg bw conmrcial zineb (89.6% pure) in water by stomach tub for up to 22 months, at which tim 10 surived; 2 had tururs (1 adenocarcinoma and 1 lyrhosarcoma of the intestine). On of 46 untreated controls still alive at 22 month develope a fibrosarcor (Anianova & Alekseev, 1970)

(p?O. 05).

249 Groups of 10 rats of each sex were given 0 (control), 500, 1000, 2500,

5000 or 10,000 mg zineb (purity unspecified) per kg of di et for 2 years. Of 15 anirls which died wi thin 1 year, 8 were aing those fed the t:o highest dose levels. Aing male anirls, there' was 1 turur-being animl in the controls, 2 fed 500 mg/kg, 3 fed 1000 mg/kg, 2 fed 2500 rr/kg, 1 fed 5000 mg/kg and 1 fed 10,000 mg/kg. Arng fanles, the oorresponding figues were l, 0, l, l, 0 and 0 ~ The tururs were malignant tururs of the lung, with the exception of an additional malignant turur in the srnl l:el of 1 male fed 10,000 mg/kg, a rn carcinoma in 1 femle fed 1000 mg/kg and a papillar adenocarcinoma of the thyroid in 1 femle fed 2500 nq/kg (Blackwell-Srth et al., 1953).

(b) Subcutaneous admnistration

Mouse: Groups of 18 male and 18 femle (C57BL/6xC3H/An)F nuce and 18 rnle and 18 femle (C57BL/6xA)F rnce were given single s.c.1 injections 1 of 1000 mg/kg hw comærcial zineb (97% pure) in 0.5% gelatine at 28 days of age and were observed until they were alut 78 weeks of age, at whch ti 16, 18, 18 and 17 mice in the four groups, respectively, were still alive. 'lur incidences were cornared with th in groups of 141, 154, 161 and 157 untreated or vehicle-injected controls that were necropsied. ln maes of the first strain, 5/18 autopsied mice had deve10pe systemc reticulum-cell sarcomas, corned with 8/141 controls (P~O. 01). Trre was no other increase in turur incidence over that in controls (NTIS, 1968).

Rat: A group of 48 non-inred rats received 20 nq/kg l: corncial zineb (89.6% pure) as a s.c. imlant in a 250 rr J:raffin pellet. Of the 6 rats still ali ve at 22 rrnths, 4 develope tUIurS (1 rnlignant hepatorn, 1 fibrosarcorn, 1 spindle-cell sarcorn and 1 rhabornosarcoma). One of 46 untreated controls, which did not received --praffin - P21lets and were still alive at 22 rrnths, developed a fibrosarcorn (Andrianova & Alekseev, 1970)

(P~O. 001).

(c) Oter exprirntal system Prenatal expsure: Of 18 pregnt fer1e A rnce that recei ved single i.p. injections of 8 mg/animl zineb (purity unspecified) during the second half of pregnancy, 11 produced a total of 38 offspring, 20 of which surived.

250 These were killed and exaed at the age of 4 rrnths, and lung adenomas were found in 6. Lung adenomas had not been observed in 4-rrnth old mice of that strain in the sam labratory (Kvitnitskaya & Kolesnichenko, 1971). 3.2 Oter relevant biological data

(a) Exerimntal system

The oral LD of zineb in rats is 1-8 g!kg bv (Ben-Dyke et al., 1970; 50 Blackwell-Srth et al.-, 1953). Groups of 4-VJek old rats VJre given 500- 10,000 mg zineb per kg of diet for 2 years; there was sone rrrtali ty aIng ferles fed 5000 and 10,000 rn!kg, and a goi trogenic effect was observed at all dose levels. Hyprplasia of the thyroid was seen in dogs gi ven up to 10,000 mg zineb per kg of diet for 1 year (Blackwell -Sr th et aL., 1953).

ln rats, the breadown of zineb (1) (Schei 1) into ethylene diamne (2) and carbon disulphide rny occur under the acid conditions of the stomach. This would account for part of the carbon disulphide that is excreted in the exhaled air (Traut et al., 1973); the reminder arises from the transformtion of ethylene bisthiurar rrnosulphide (3) into EI (4) (Engst et al., 1971). The absorbed ethylene diame (2) 1S patly elirnated via the lungs as carbon dioxide and the rerinder in ionized forr in the urine. 1 Ethylene bis-isothiocanate " for which two alternative strctures (5 and 6) are proposed*, possibly ethylene bisthiuram rrnosulphide (3) and another unidentified zineb rntablite are also detected in th urine (Traut et al., 1973).

When rats were dosed with 100 rn!kg bv/day for periods of up to 6 rrnths, first pregnancies were retarded, and there was an increased incidence of sterility and foetal resorption. The resulting neonates had crooked tails and suffered rrst noticeably fror a reduced or retarded weight gain; there were sorn early postnatal deaths. Toxic effects also occured

*The Working Group considered the probable strcture to be that represented in (6).

251 SC 1

HN-CH2-CH2-NH ~./ C1 /~Zn ¿S"" C1 ~/'-/5 5 CD (CH2NH2J+ 2 C52 ~ l

~~: :-: ~-:H) 1 Il H 5 l ~ W , rCH2-CH2 .. CH2-CH2 /N-C CH1 2 "'5 N1 1N N1 1N CH2 / ,\/ '" \N-C C C=5 \/C Il H1 Il5 0 5-51 1 5-C=55 l æ C! .. r "'

H 1

CH2/N\ C52 + 1 C=5 CH2/ "N 1 50 2-/ H CD 4

252 in those neonates tht continued to receive zineb at the sa dose level as their paents (Ryazanova, 1967).

Single oral doses of 2-8 g!kg l: adrnistered to pregnant rats on day 11 or 13 of pregancy resulted in congenital abnormlities in 12-100% of the foetuses. The maimum dose level at which no teratogenic effect was observed was 1 g!kg bw: no adverse effect on the intra-uterine developmet of the progeny was observed when this dose was given daily to groups of rats from day 2 to day 21 of pregnancy, or when the rats were exsed by inhalation to a concentration of 100 mg zineb/m3 for 4 hours per day from day 4 of pregncy (Petrova-Vergieva & lvaova-Cheshanska, 1971, 1973) . (b) Ma One person suffering from hypatalasaera developed sulphaerglo- binaema, haerlytic anaera and Heinz l:y formtion after contact with zineb (Pinkas et al., 1963). An increase in the numr of chorrsorn abrrations in peripheral bloo 1 yrphoces was observed in a study of persons occupationally expsed to zineb (Pilinskaya, 1974).

ET (4) (Scher 1) produced thyroid cacinomas ln rats and increased the incidence of li ver-cell tururs in two strains of mice after i ts oral adrnistration (lAC, 1974). 3. 3 Case reports and epidemological studies

No data were available to the WJrking Group.

4. Comænts on Data Reported and Evaluation 4. 1 Animl data

Zineb produced an increased incidence of lung tururs after its oral admistration to mice of one strain. Systerc reticulumcell sarcomas were observed in mice and a variety of sarcoms in rats after its subutaeous admistration. No increases in turur incidences were observed in tw other strains of mice and in two lir ted studies in rats following oral admstration. The available data do not allow an evauation of the

253 carcinogenici ty of zineb to be made. 4.2 Hum data

No case reports or epidemological studies were available to the Working Group.

254 5. References

Andrianova, M.M. & Aleksev, LV. (1970) On the cacinogenic properties of the pesticides sevine, rn, cirar and cineb. Vop. Pitan., 29, 71-74

Ben-Dyke, R., Sanderson, D.M. & Noakes, D.N. (1970) Acte toxicity data for pesticides. Wld Rev. Pest. Control, 9, 119-127

Berg, G.L., ed. (1976) Far Chcals Handbk 1975, Willoughby, Ohio, Meister, p. D 222 Bighi, C. (1964) Microdeterrnation of dithiocarbates by gas chrcmto- graphy. J. Chomat., 14, 348-354

Blackwll -Sr th, R., Jr, Finegan, J. K., Lasan, P. S., Saoun, P. F ., Dreyfuss, M.L. & Haag, H.B. (1953) Toxicologic studes on zinc and discxium ethylene bisdithiocbates. J. Phacol. ex. Ther., 109, 159-166

Blasez, C.H. (1973) Residue deterration of ethylenethourea (2-irda- zolidinethone) frou tomto foliage, sail and water. J. agric. Fd Chem., 21, 330-332

Bontoyan, W.R. & lDker, J.B. (1973) Deadation of cacial ethylene bisdithocbate formlations to ethylenethourea under elevated temrature and hurdi ty . J. agric. Fd Cl., 21, 338- 342

Bontoyan, W.R., Loker, J.B., Kaser, T.E., Giang, P. & Olive, B.M. (1972) Sureyof ethlenethourea in ccrcial ethylenebisdithiocte formations. J. Ass. off. analyt. 01., 55, 923-925

Budnikov, G.K., Toropova, V.F., Ulakovich, N.A. & Viter, 1.P. (1974) Electrochecal bevior of dithocrbates on a rrcu electrode. III. Polarogaphic study of fungicides of dithocarbate ty in organc solvents. Zh. anlyt. Kh., 29, 1204-1209

Chernov, O.V. & Khitseno, 1.1. (1969) Blastoenic properties of sor deri vati ves of di thiocarbac acid. Vop. Onol., 15, 71-74

Corneliussen, P .E. (1972) Pesticide residues in total diet sarles. VI. Pest. Monit. J., 5, 313-310

Engst, R., Schnak, W. & I.renz, H.-J. (1971) Untersuchungen zum Heta- bolism der Fungiciden 1-thylen-bis-dithocbate .Meb, Zineb und Na. V. Zur Toxikologie der Abbauproduke. Z. Lesmtt.-Unter- such., 146, 91-97 Fishbin, L. (1975) Chcmtogaphy of Environintal Hazards, VoL. 3, Pesticides, Amterda, Elsevier, pp. 676-692 Fishbin, L. & Zielin, i'J.L., Jr (1967) Chnatogaphy of caiamtes. Chmat. Rev., 9, 37-101

255 Hester, W.F. (1943) Fugicidal corrsition. us Patent 2,317,765, April 27, to Röhm & Haas Co. lAC (1974) IA Monogaphs on the Evluation of Cacinogenic Risk of Chemcals to Ma, 7.-, So Anti-thyroid and Related Substaces, Nitro- furans and Industrial Chemcals, Lyon, pp. 45-52

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrcelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Falk, H.L., Gart, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and industrial chemcals for turrigenici ty in mice: a prelirnar note. J. nat. Cancer Inst., 42,1101-1114 Japanese Ministry of Agriculture and Forestry (1975) Noaku Yoran (Agri- cultural Chemcals Anual), 1975, Division of Plant Disease Prevention, Tokyo, Takeo Endo, pp. 17-19, 26, 89, 101, 265, 301 Kvitnitskaya, V.A. & Kolesnicheno, T.S. (1971) On the tranplacental blastorrogenous action of cineb on the progeny of mice. Vop. Pitan., 30, 49-50

Manske, D.D. & Corneliussen, P.E. (1974) Pesticide residues in total diet samles. VII. Pest. ~bnit. J., 8, 110-114

Newsorr, W.H. (1974) A rrthod for deterring ethylenebis (dithocbate) residues on foo crops as bis (trifluoroacetardo) ethane . J. agric. Fd Chem., 22, 886-889

NTIS (National Technical Informtion Service) (1968) Evluation of Cacino- genic, Teratogenic and Mutagenic Acti vi ties of Selected Pesticides and Industrial Chercals, Vol. l, Carcinogenic Study, Washington IX, US Depant of Corrrce Petrova-Vergieva, T. & Ivanova-Cheshanka, L. (1971) On the teratogenic effect of zinc ethylenebisdithocarbate (zineb) in rats. Ekp. l1. Morfol., 10, 226-230 Petrova-Vergieva, T. & Ivanova-Chershanka, L. (1973) Assessmt of the teratagenic acti vi ty of di thiocarbate fungicides. Fd Cosmt. Toxicol., IL, 239-244 Pilinskaya, M.A. (1974) Results of cyogenetic exanation of persons occupationally contacting with the fungicide zineb. Geetika, 10, 140- 146

Pinkas, J., Djaldetti, M., Joshua, H., Resnick, C. & de Vries, A. (1963) Sulfheilobinema and acute herlytic anema with Heinz boes following contact with a fungicide - zinc ethylene bisdithiocarbamte - in a subject with glucose-6-phosphate dehydrogense deficiency and hyptalasera. Bloo, 2l, 484-494

256 Ryazanova, R.A. (1967) Effect of the fungicides ciram and cineb on the generative function of test anls. Gig. i Sanit., 32, 26-30 Spencer, E. Y. (1973) Guide to the Chemcals Used ln Crop Protection, 6th 00., London, Ontario, Uni versi ty of Western Ontario, Research Branch, Agriculture Cada, Pulication 1093, p. 537 Stecher, P .G., ed. (1968) The Merck Index, 8th ed., Raay, ID, Merck & Co., p. 1131

Stevenson, A. (1972) A simle color spot test for distinguishing betwen rneb, zineb, macozeb, and selected mixtures. J. Ass. off. anl yt. Chem., 55, 939-941

Supin, G.S., Kliseno, M.A. & Vekshtein, M.S. (1973) Polarographic deter- mination of residual arunts of fungicide as ditliocarbonic acid derivatives. Khir. selsk. Khozyaistve, 11, 840-842 Truhaut, R., Fujita, M., Lich, N.P. & Chigneau, M. (1973) Etude des trans- formtions métaliques du zinèbe (éthylènebisdithiocarbarte de zinc) chez le rat. C.R. Acad. Sci. (Paris), 276, 229-233

US Depat of Agriculture (1975) 'T Pesticide Review 1974, Washington IX, US Governmt Printing Office, p. 11 US Environmtal Protection Agency (1974) EPA Candium of Reistered Pesticides, Vol. 2, Washington IX, US Governt Printing Office, pp. Z-lO-OO.Ol - Z-10-OO.17

US International Trade Conmssion (1975) Synthe tic Organic Chcals, US Production and Sales of Pesticides and Related Product, 1974 Pre- lirnar, US Governnt Printing Office, i'Jashington De, p. 3

US Tariff Commssion (1962) Synthetic Organic Chercals, US Production and Sales, 1961, TC Pulication 72, US Governt Printing Office, Washington De, p. 50

US Tariff Commssion (1969) Sythetic Organic Chcals, US Production and Sales, 1968, TC Pulication 327, US Governt Printing Office, Washington De, p. 199

Watts, R.R., Storherr, R.W. & Onley, J.H. (1974) Effects of coking on ethy- lenebisdithocbate degradation to ethylene thourea. BuL. environr. Contar. Tbxicol., 12, 224-226

WHO (1975a) 1974 Evaluations of some peticide residues in fexxL Wld Hlth Org. Pest. Res. Ser., No. 4, pp. 261-262

WHO (1975b) Pesticide residues in fcx. Report of the 1974 Joint Meting of the FAO WJrking Party of Exprts on Pesticide Reidues and the WH Exert Corrttee on Pesticide Residues. wid Hlth Org. techn. Rep. Ser., No. 574, pp. 26-30

257 ZIRA

1. Chcal and Physical Data 1.1 Synonym and trade nas

Cher. Abstr. Re. SeriaI No.: 137-30-4 Cher. Abstr. Nar: Bis (dimthylcabaithoata-S-,S') zinc Bis (dimthy ldi thocbato) zinc; dimthy lcabai thioic acid, zinc comlex; dimthylcarbathoic acid, zinc salt; dimthyl- dithiocbate zinc salt; dithyldithocarbac acid, zinc salt; irthyl zirte; ræthyl ziram; zinc bis (dithyldithocarbate) ; zinc bis (dimthyldithocbayl)disulphide; zinc dithyl dithocarbate; zinc N-dimthyldithocarbate; zinc N-, N-dithyldithio- carbate Accelerator L; Aceta ZDID; Aceto ZDID; Alcoba ZM; Cabazinc; Corona Corozate; Corozate; Cu; Cyte; Eptac 1; Fuclasin; Fulasin; Hexzir; Kaba "Wte; Methasan; Methzate; Mezene; Milb; Mi1b; !-lurar; Orchard brand Ziram; Pczol Z-forte; Rhodiacid; Soxinal PZ; Soxinol PZ; Tricarbax Z; Triscal; Vancide MZ-96; Vulcacue ZM; Vulcit L; Vulkacite L; Z 75; Z-C Spray; Zerlate; Zirte; zirar; Zirberk; Ziride; Zitox 1.2 Chemcal fonrla and rrlecular v.ight HJC S S ClJ '\ /'\,/'\ 1 H /N-C\JC SJ'\ S iC-N\CH J

C6H12N2S 4 Zn MoL. wt: 305.8

259 1.3 Chercal and physical propeies of the substance

From Stecher (1968), unless otherwise speified

(a) Description: White IXder or crystals o (b) Melting-point: 250 C (crystals) ¡ l4SoC (dust)

(c) Solubility: Insoluble in water¡ slightly soluble ln carbon tetrachloride, diethyl ether and ethanol (0.2 g/100 ml at 250C) ¡ O. 5 g or less are soluble ln 100 ml of acetone, bezene and other non-polar solvents. 1. 4 Technical products and inuri ties

Zirar is available in the US as dusts oontaining 3.5-76% of the chercal, as wettale poers containing 30-96% of the chemcal, as aqueous suspesions containing 30-40% of the chemcal and as a 0.1% paste (US Environrntal Protection Agency, 1973).

ln Japan, zirar is available as a technical grade product contaning 98% of the chemcal and less than 0.5% water, 0.4-0.5% soium chloride and 1.0-1.1% other inurities (rrstly zinc ræthyldithiocarbate) (Japaese Ministr of Agriculture & Forestr, 1975).

2 . Production, Use, Occurrence and Anal ysis

For imrtant background informtion on this section, see preamle, p. 15. 2. 1 Production and use Zirar can be prepaed from zinc oxide, dithylamne and carbon disulphide (Stecher, 1968). It was first produced corrrcially in the US as a fungicide in 1947 (US Tariff Corssion, 1949) but had been used as a rubber accelerator since 1943 (US Tariff Commssion, 1945). ln 1973, zirar was produced in the US by eight compies whose ccmined production amunted to 1 million kg.

It is estirted ta be produced in ltay at a rate of 1-5 million kg anuall y, and in the Beelux countries, the Federal Republic of Gey,

260 France, Spain and the OK ln arunts of less th 1 million kg anually ln each country. Zirar was first prcxuced in Japan ln 1969; approxitely 2.7 thousand kg were produced in 1970 and alut 700 kg in 1973. 'l Japanese companies are current1y prcxucing this chemcal (Japanese Miistr of Agricuture & Forestr, 1975).

The usefulness of zirar as a fungicide was first observed in 1944 (McCallan, 1967). It is registered in the US for use on 24 frut and vegetale crops and on several comnrcial and houseold ornaintal flo.ers (US Environrntal Protection Agency, 1973). A residue tolerance of 7 rrjkg, calculated as zinc ethylenebisdithiocarbate, has been established in the US on abut 50 raw agricultural cornities (US Ccxe of Federal Regations, 1974) . Ziram is also used in the rur-processing industr as an accelerator or prorrter which functions by interacting wi th sulphur to increase the rate of vulcanization (Wolfe, 1971).

Snll arunts are used in indus trial fungicides, in cornination wi th 2-rnrcaptobenzothiazole, in adhesives (including those used in foo packaging) ,

paper coatings (for non-food contact), indus trial cooling water, latex-coated articles, neoprene, paper and paperboard, plastics (polyethylene and poly- styrene) and textiles (US Environmtal Protection Agency, 1973).

ln Decemr 1974, the Joint Meeting of the FAO Working Party of Exrts on Pesticide Residues and the WHO Exprt Corn ttee on Pesticide Residues established a revised temrar acceptale dai1y intae for ma of 0-0.005 rnjkg bw for all dithiocarbate fungicides (v-0, 1975a,b). 2.2 Occurence

Zirar is not known to occu as a natural prcxuct.

As par of the 'Total Diet Prograr' of the US Foo and Drug Admnistra- tion, 360 corrsite foo sales were collected anually during the pericx 1964-1970, prepared as for consumtion and ana1ysed for dithocarbamte content. A maimum of 4 compsites contained detectale levels of di thiocarbates in any single year (Corneliussen, 1972), and in at least one

261 yea no di thiocarbate was detected. On the basis of these resul ts , anl ysis for di thiocbartes in this progan was discontinued after 1970 (Maske & Corneliussen, 1974). 2 . 3 Anal ysis

Methods for the chr()togaphic analysis of carbates, including ziram, have been reviewed (Fishbin & Zielinski, 1967).

Gas chromatography has be used to detere zirar residues ln foo sarles (McIe & ~lly, 1969). Thn-layer chromtographie nethoos have been describd in which the presence of ziram was shCM by spraying with a soum azide-iodæ regent (Klsenko & Vekshtein, 1973a) or with cupric chloride hydroxylarne (Fishbin, 1975). ln another iæthod, ziram was hydrolysed and the prooucts reacted to yield strongly fluorescent derivatives (van Hoof & Heyndrickx, 1973) which \ære sepaated by thn-layer chrortography and visualized under ultra-violet light. Ths procedure was capable of deinstrating the presence of 20 ng zirar. Methods for the detection of zirar based on polarogaphy (Budikov et al., 1974 ¡ Kliseno & Vekshtein, 1973b¡ Supin et al., 1973) and colorimtry (Ragaswam et al., 1970) have ben describ.

3. Biological Data Relevant ta the Evluation of Cacinogenic Risk to Ma 3 . 1 Carcinogenici ty and related studies in animls

(a) Oral admistration

MJuse: Groups of 18 male and 18 femle (C57BL/6xC3H/Anf)F rnce and 1 18 male and 18 ferle (C57BL/6xA) F mice received comrrcial zirar 1 (m.p. 242-2570c) according to the following schedule: 4.6 rr!kg l: in gelatine at 7 days of age by st()ch tub and the sa aIunt (not adjusted for increasing 1xy weight) daily up to 4 \æeks of age¡ subseqently, the mice were given 15 mg ziram per kg of diet. Th dose was the maum tolerated dose for infant and young rnce but not necessarily sa for adults. The eximnt was termnated when the animls \ære abut 78 \æeks of age, at which tim 15, 18, 17 and 17 mice in the four groups, respcti vel y, were

262 still alive. Ttur incidences were corned with those observed anng 79-90 necropsied mice of each sex and strain, whch ei thr had be untreate or had received gelatine only: the incidences ~re not signficantly greater (P:?O .05) for any tlIur typ in any sex-strain subroup or in the CXrrined sexes of either strain (Innes et aL., 1969; NlIS,1968).

Of 82 strain A and 54 C57BL mice given ~ekly doses of 75 ID/kg l: ziram (purity unspeified) by st.ch tub for 20 wes and killed 6 Ilnths after the begining of the exrirt, 42/82 (51%) and 4/54 (7%) developed lung adenoms, corned with 23/54 (43%) and 0/28 controls (Chernov & Khitsenko, 1969) (P:?O. 05 J .

Rat: Of 60 random-bred rats given 70 ID/kg b. cxrcial ziram (90.5% pure) twice weely in water by stomch tub for up ta 22 rrnth, 10 surived 22 rnnths, and 4 develope tururs (2 malignant hepators, 2 fibrosarcos). Arn::mg 46 untreated controls still alive at 22 rrnths, 1 develope a fibro- sarcoma (Andrianova & Alekseev, 1970) (P.:0.01J.

Groups of 25 male and 25 ferle 4-~ek old Rochester (ex-Wista) rats were fed diets containing 0, 25, 250 or 2500 ID ziram (puri ty not speified) per kg of diet for 2 yeas. The lifespans of l:th treate an control rats were betwe 600 and 700 days. Of 11 turous foun in treated rats, 3 malignant tUIurs of the pituitar and 2 thyroid adenomas occured in rats given the highest dose; a hyprplastic thyroid was obsered in a rat given the lcwst dose. Seven tUIurs were see in control rats, but their locations were not indicated (Hodge et aL., 1956). (b) Subtaeous admnistration

!-use: Groups of 18 male and 18 ferle (C57BL/6xC3H/An) F mice and 1 18 male and 18 ferle (C57BL/6xA)F mice ~re given single s.c.injections 1 of 46.4 rn/kg bw conrrcial ziram (m.p. 242-2570C) in 0.5% gelatine on the 28th day of life and were observed until they were aOut 78 wes of age, a t which t.i 16, 17, 17 and 13 mice in the four groups, respecti vel y, were still alive. Ttur incidences were coed with those ofgrs of 141, 154, 161 and 157 untreated or vehicle-injected contrls that were necropsied. Incidences were not increased (P:?0.05) for any turur ty in any sex-strain subroup or in the cxined sexes of either strain

263 (NTIS, 1968) (The Working Group noted that a negative result obtained after a single s.c. injection may not be an adeqate basis for discounting carcinogenici ty ) .

Rat: Of 48 randornbred rats given 15 rr!kg l: zirar (90.5% pure) in a subutaeously imlanted 250 rr paaffin pellet, 10 surived 22 ITnths, and 3 develope tururs (1 hepatoma, 1 fibrosarcor and 1 lynhosarcoIT of the intestine). No tururs v.re observed at the site of imlantation. Of 46 controls, which did not receive paaffin pellets and which were still alive at 22 ITnths, 1 develope a fibrosarcorn (Andrianova & Alekseev, 1970) (Po(O. 02). 3.2 Oter relevant biological data (a) Exrimtal system

The oral LD of zirar in rats is 1400 rr!kg bw, and the lethal ranges 50 of oral doses in guea-pigs and rabbits are 100-150 and 100-1020 rn!kg hw, respectively; dogs tolerated doses of 25 rn!kg l:/day for one rmnth (Hodge et aL., 1952), but convusions occurred in animls given the dose daily for one year (Hodge et al., 1956).

A glycogenolytic response was elicited in rats by an i.p. injection of 10 mg ziramg l: (Dailey et al., 1969). Like rrst dithocarbarna:tes, zirar induces the accuulation of acetaldehyde in the bloo of rats recei ving ethanol at the sar tim (van Loten, 1972).

Admnistration of zirar with nitrite in aqueous solution to rats by stornch tub led to the formtion of detectable amunts of N-nitroso- direthylarne in the stornch contents 15 miutes later (Eisenbrand et aL., 1974) .

Little direct work has been done on ziram rrtalism (Izrrova, 1972); Izmirova & Marinov (1972) found water-soluble metalites in the bloo, kidneys, li vers, ovaries, spleens and thyroids of femle rats 24 hours after oral dosing. Unchanged ziram was excreted in the faeces. The presence of water-soluble rrtabli tes indicates the generation of the dimthyldithiocarbate ion in the storch after ingestion of zirar; the work of Hodgson et al. (1975) on ferba is therefore relevant.

264 Admnistration of 50 rn/kg bt/day to mice for 15 days substatially reduced the fertility and fecundity of the femles but did not affect the fertility of males (Ghezzo et al., 1972).

No increase in the numr of recessive lethals in Drosophila melanogaster was obtained with zirar; hc:ever, only 929 chrOITsorns were tested (Benes & Srar, 1969). Siebrt et aL. (1970) found no significat increase in gene conversion in Saccharomyces cerevisiae; rntalic activation system were l1t used in these tests. An increased numr of chonsorn abrrations in rntaphases of bone-marow cells was found in rnce treated with 100 rn/kg bt orally (Antonovich et al., 1971).

(b) Ma

A fatal case of acute ziram poisoning has been describd (Buklan, 1974).

Pilinskaya (1970) reported approxitely six tims higher freqency of chrorrsorn and chrortid abrrations in netaphases of cul tured peripheral lymhoces from v.rkers hadling zirar. Expsure of cutured hum r:ri- pheral lymhoctes to 0.003 to 0.06 m~/rn of zirar resulted in a dose- dependent increase in the numr of chroITsorn and chromatid abrrations (Pilinskaya, 1971). For a discussion of the interaction of cornunds such as zirar wi th ethanol in the bloo, see 'Geeral Rerrks on Carbates, Thiocarbates and Carbazides', pp. 28-29. 3 . 3 Case reports and epidemological studies

No data were available to the Working Group.

4. Conmts on Data Reported and Evluation 4 . 1 Animl data

Oral admistration of zirar increased the incidence of li ver and subutaneous tururs in one study in rats, with a lirted numr of sur ving animls; i ts subtaneous admistration induced a lower yield of the sam typs of tururs. ln one study by oral admistration in two strains of mice, no carcinogenic effect was observed. A furer

265 study by oral admnistration in rats could not te evaluated due to inadeqte reporting. The lir ted data available do not allCM an evaluation of the carcinoenicity of ziram to be made. Ziram ca react wi th ni tri te under mildl y acid conditions, sirulating those in the hun stonch, to forr N-nitrosodimthylarne, which has been sha- to be carcinogenic in seven animl spies (IA, 1972). 4.2 Hum data

No case reports or epidemological studies were available to the Working Group.

266 5. References

Andrianova, M.M. & Alekseev, LV. (1970) On the cacinogenic properties of the pesticides sevine, rneb, cirar and cineb. Vop. Pitan., 29, 71-74

Antonovich, E.A., Chepynoga, O.P., Chernov, O.V., Rjazanova, P.A., Vekshtein, M.S., Martson, V.S., Mason, L.V., Sarsh, L.V., Pilinskaya, M.A., Kuriny, L.I., Balin, P.N., Khitsenko, 1.1., Zastavnjuk, N.P. & Zaolorozhnaja, N.A. (1971) Toxicity of dithocarbates and their fate in warlooed animls. ln: Antonovich, E.A., Bojanovska, A., Engst, P. et al., eds, Proceedings of the Symsium on Toxicolog and Anal ytical Chemstry of Di thocarbates, Durovnic, 1970, Berad, pp. 3-20 Benes, V. & Sram, R. (1969) Mutagenic acti vi ty of sone pesticides in Drosophi la me lanogaster. Industr. Me. Surg., 38, 50-52

Budnikov, G.K., Toropva, V.F., Ulakovich, N.A. & Viter, LP. (1974) Electrochemcal beavior of dithocarbates on a rnrcur electrode. III. Polarographic study of fungicides of dithiocarbate typ in organic solvents. Zh. anlyt. Kh., 29, 1204-1209

Buklan, A.1. (1974) Acute zirar poisoning. Sud.-rr. Ekspert., 17, 51 Chernov, o. V . & Kh tsenko , 1. L . (1969) Blastomenic properties of sorn derivatives of dithiocarbac acid. Vop. Onol., 15, 71-74

Corneliussen, P.E. (1972) Pesticide residues in total diet samles. VI. Pest. Monit. J., 5, 313-330

Dailey, R.E., Leavens, C.L. & Walton, M.S. (1969) Effect of certain dimthyldithiocarbarte salts on sorn intenædiates of the glycolytic pathway in v~vo. J. agric. Fd Che., 17, 827- 828 Eisenrand, G., Ungerer, O. & Preussma, R. (1974) Rapid forntion of carcinogenic N-ni trosames by interaction of ni tri te wi th fungicides derived from dithocarbac acid in vitro under sirulated gastric conditions and in vivo in the rat storrch. Fd Cosirt. Toxicol., 12, 229-232

Fishbin, L. (1975) Chortography of Environmntal Hazards, Vol. 3, Pesticides, Amterdam, Elsevier, pp. 676-692 Fishbin, L. & Zielinski, W .L., Jr (1967) Chorntography of cabartes. Chromat. Rev., 9, 37-101

Ghezzo, F., Coradini, L., Guglielmni, C. & Ninfo, V. (1972) L'azione tossica die ditiocarbati su sistem enzirtici. Qud. Sclavo Diagn., 8, 485-494

267 Hodge, H.C., Maynard, E.A., Dos, W., Blanchet, H.J., Jr & Jones, C.K. (1952) Acute and short-terr oral toxicity tests of feric dithyldithocar- barte (ferba) and zinc dithyldithocarbate (zirar). J. Arr. phar. Ass., 41, 662-665

Hodge, H.C., Maynard, E.A., Dos, W.L., Coe, R.D., Jr & Steadr, L.T. (1956) Chronic oral toxicity of ferric dithyldithiocarbamte (ferba) and zinc dimthyldithiocarba.te (ziram). J. PharmcoL. ex. Ther., 118, 174- 181 Hodgson, J .R., Hoch, J .C., Castles, T .R., Helton, D.O. & Le, C.C. (1975) Metalisr and disposition of ferba in the rat. Toxicol. appl. Pharcol., 33, 505-513

van Hoof, F. & Heyndrickx, A. (1973) Thn- layer chorntographic-spetro- photofluorimtric rnthods for the determnation of ditho- and tho- carbartes after hydrolysis and coupling with NBD-CL. Ghent. Rijks- univ. Fac. Ladbl. Med., 38, 911-916 lAC (1972) IA Monogaphs on the Evluation of Carcinogenic Risk of Chemcals to Ma, l, Lyon, pp. 95-106

Innes, J.R.M., Ulland, B.M., Valerio, M.G., Petrcelli, L., Fishbin, L., Hart, E.R., Pallotta, A.J., Bates, R.R., Fal, H.L., Gar, J.J., Klein, M., Mitchell, 1. & Peters, J. (1969) Bioassay of pesticides and indus trial chercals for turrigenici ty in rnce: a prelirar note. J. nat. Cancer Inst., 42,1101-1114

Izmirova, N. (1972) A study of the water- and chloroforrsoluble netalites of 35S-zirar by rnans of paper and thn-layer chomatogaphy. Ekp. Me. Morfol., 11, 240-243

Izmirova, N. & Marinov, V. (1972) Distribution and excretion of sulphur- 3S-lablled zirar (zinc dimthyldithocarbate) and its rntablic products 24 hours after oral admnistration. Eksp. Me. !-rfoL., Il, 152- 156

Japanese Ministr of Agriculture and Forestr (1975) Noyaku Yoran (Agri- cultural Chercals Anual), 1975, Division of Plant Disease Prevention, Tbkyo, Takeo Endo, pp. 17-18, 254, 267-268

Klisenko, M.A. & Vekshtein, M.S. (1973a) Determation of zirar, curazin-II, tetrarthylthiurar disulfide ('I), and their degradation proucts (tetrarthy 1 thiourea, dimthy lanm::mium dithy ldi thocarbate, and sulfur) in water using thn- layer chrorntography. Metody Opred. Pestits. Vode, l, 60-64 Klisenko, M.A. & Vekshtein, M.S. (1973b) Polarographic determnation of residual amunts of fungicide-derivatives of dithiocarbac acid. Khir. selsk. Khozyarstne, 11, 840-842

268 van Loen, M.J. (1972) De Dithiocarbaat-Alcohol-Reactie bij de Rat, Terborg, The Nether lands, Bedri j f FA. L3rs, p. 40

Maske, D.D. & Corneliussen, P.E. (1974) Pesticide residues in total diet. samles. VII. Pest. Monit. J., 8, 110-114

Mcallan, S.E.A. (1967) History of fungicides. ln: Torgeson, D.C., ed. Fugicides, VoL. l, New York, Academc Press, p. 14 McLe, H.A. & Mcully, K.A. (1969) Head space gas procedure for screeing foo sarles for dithiocarbate pesticide residues. J. Ass. off. analyt. Chem., 1226-1230

NTIS (National Technical Inforrtion Service) (1968) Evaluation of Carcino- genic, Teratogenic and Mutagenic Activities of Selected Pesticides and Industr ial Chemcals, Vol. l, Carcinogenic Study, Washington IX, US Deparent of Commrce Pilinskaya, M.A. (1970) Chromsornl abrrations in persons handling zirar under industrial conditions. Geetika, 6, 157-163

Pilinskaya, M.A. (1971) Cyogenetic action of the fungicide zirar in a culture of hum lymphoces in vitro. Geetika, 7, 138-143 Ragaswar, J. R., Poornim, P. & Majurer, S. K. (1970) Rapid colorimtrie method for estimtion of ferbc and ziram residues on grain. J. Ass. off. analyt. Chem., 53, 1043-1044 Siebrt, D., Zimrm, F .K. & Lerle, E. (1970) Geetic effects of fungicides. Mutation Res., 10, 533-543

Stecher, P.G., ed. (1968) The Merck Index, 8th ed., Raay, NJ, Merck & Co., p. 1131

Supin, G.S., Kliseno, M.A. & Vekshtein, M.S. (1973) Polarographic deter- mination of residual amunts of fungicide as dithiocarbonic acid derivatives. Kh. Sel. Khoz., 11, 840-842

US Code of Federal Regulations (1974) Protection of Environmnt, Title 40, part. 180.116, Washington IX, US Governt Printing Office, p. 249 US Environrntal Protection Agency (1973) EPA Comdium of Registered Pesticides, Washington De, US Governnt Printing Office, p. I-Z-ll- 00.01

US Tariff Commssion (1945) Synthetic Organic Chercals, us Production and Sales, 1941-43, Report No. 153, Second Series, Washington DC, US Govern- ment Printing Office, p. 118

269 US Tariff Corrssion (1949) Synthetic Organic Chcals, US Production and Sales, 1947, Report No. 162, Secnd Seies, Washington IX, US Govenunt Printing Office, p. 145

\"l0 (1975a) 1974 Evaluations of sor pesticide residues in foo. Wld Hlth Org. Pest. Res. Ser., No. 4, pp. 261-262

WHO (1975b) Pesticide residues in foo. Report of the 1974 Joint Meting of the FAO Working Pary of Exrts on Pesticide Residues and the WHO Exrt Conmttee on Pesticide Residues. Wld Hlth Org. techn. Rep. Ser., No. 574, pp. 26-28 ivolfe, J.R., Jr (1971) Vulcanzation. ln: Bikalis, N.M., ed., Encyclopedia of Pol yrr Science and Technolog, Vol. 14, New York, Interscience, pp. 740-741, 747-748

270 SUPPLEY cxRRGEA TO VOLU 1 - 11

Corrigenda covering Volurs 1 - 6 appeared in Volur 7, others appeed in Volums 8, 10 and 11. Listed below are furer errors that have since been brought to our attention.

Volur 9 p. 251 para 1 line 3 rep lace 112 rn!kg by 1112 rn!kg

Volum 10 p. 73 1.3 (c) replace Refractive index: by Optical rotation: p. 200 2.1 line 4 replace (+) by (l)

Volur 11 p. 116 1.3 (c) replace 19o C by -190 C

271 CUIV INEX 'I IA MJHS ON TH EVATION OF CAllIC RISK OF CHCA 'I MA Nurrs underlined indicate volur, and nunrs in italics indicate page. References to corrigenda are given in paentheses. Acetade 7,197 Actinorqcins 10,29 Adiamcin 10,43 Aflatoxis 1,145 (corr. 7, 319)

( corr. 8 , 349) 10,51 Aldrin 2,25 Amanth 8,41 para-Amoazobenzene ~,53 ortho-Amnoazotoluene ~,61 (corr. 11,295) 4-Amnobipheyl 1,74 (corr. 10,343) 2-Am-5- (5-nitro-2-furl) -l, 3, 4-thiadiazole 7,143 Amtrole 7,31 Anaesthetics, volatile 11,285 Aniline !,27 (corr. 7,320) Apholate 9,31 Arar te (ß 5,39 Arsenic and inorganic arsenic counds ~,48 Arsenc (inorganic) Arsenc petaxide Arsenic trioxide Calcium arseate Calcium arseni te Potassium arsente Potassium arseni te Soium arsenate Soium arsei te Asbestos 2,17 (corr. 7, 319) Arsite Anthophyllite

273 Chsotile Crocidoli te Aurarne 1,69 (corr . -l, 319) Azaserine 10 , 73 (corr . 12,271 ) Aziridine 9,37 2- (1 -Aziridiny 1) ethol 9,47 Aziridy 1 benzoqinone 9,51 Azobenzene 8,75 Benz (c J acridine 3,241 Benz (a J anthacene 3,45 Benzene 7,203 (corr. 11,295) Bezidine 1,80 Benzo(b Jfluoranthene 3,69 Bezo(j J fluoranthene 3,82 Benzo (a Jpyrene 3,91 Bezo (e J pyrene 3,137 Benzy 1 chloride 11,217 Beryllium and beryllium caunds 1,17 Beryl ore Beryllium oxide Beryllium phosphate Beryllium sulphate BHC (techncal grades) 5,47 Bis (l-aziridiyl)rrrplinophosphine sulphide 9,55 Bis (2-chloroethyl) ether 9,117 N, N-l3s (2-corothyl) -2-naphth1ane 4,119 Bis (chlorcmthy 1) ethr 4,231 1,4-Butanediol dinthesulphonate 4,247 ß-Butyrolactone 11,225 y-Butyrolactone 11 , 231 Cadnum and cadnum caTunds 2,74 11,39 Cadnum acetate Cadnum carbonate Cadnum chloride

274 Cadmum oxide Cadmum paer Cadmum sulphate Cadmum sulphide Catharidin 10 , 79 Caba 1 12 , 37 Carbon tetrachloride l,53 Cariisine 8,83 Chlorarucil 9,125 Chloramhenicol 10 , 85 Chlormdinone acetate 6,149 Chlorobezilate 5,75 Chloroforr 1,61 Chloraæthy 1 rnthyl ether 4,239 Chloropropha 12 , 55 Cholesterol 10 , 99 Chanum and inorganic chrorum caunds 2,100 Baium chromate Calcium chrante Chanc chrante Chanc oxide Chrorum acetate Chrorum carbonate Chromium dioxide Chromium phosphate Chrorum trioxide Lead chromte Potassium chrte Potassium dichrante Soium chromate Soium dichromte Strontium chromate Zinc chromate hydroxide Chsene 3,159

275 Chrsoidine ~,91 C. 1. Dispese Yellow J ~,97 Ci trs Red No. 2 8,101 Coumin 10 , 11 3

Cycasin l-,157 ( carr. 7.- 319) 10,121 Cyclochlorotine 10,139 Cyclophosphade 9,135 Daunomycin 10,145 D & C Re No. 9 ~,107 DDT and associate substaces 5,83 (carr . 2,320) DDD (TDE) DDE Diacety lanoazotoluene 8,113 Diallate 12 , 69 2, 6-Diarno- 3- (pheny lazo) pyridine (hydrochloride) 8,117 Diazorthane 7,223 Dibnz(a~ h)acridine 1.- 247 Dibz (a~ j) acridine 3,254 Dibnz(a~ h)anthacene 1., 1 78 7H-Dibnzo(c~ g )carbazole 3,260 Dibnzo(h~ rst )petaphene 3,197 Dibnzo(a~ e)pyrene 3,201 Dibnzo(a~ h)pyrene 1.,207 Dibzo(a~ i)pyrene 3,215 Dibzo(a~ l)pyrene 1.,224 o rtho-Dichlorobezene 7,231 para-Dichlorobenzene 7,231 3, 3 1 -Dichlorobenzidine 4,49 Dieldrin 5,125 Diepoxybutane 11 , 11 5 (corr. 11,271) 1,2-Diethylhydrazine 4,153 Diethylstilbstrol 6,55 Diethyl sulphate 4,277

276 Diglycidyl resorcinol ether 11 , 125 Dihydrosafrole 1,170 10,233 Dimthsterone 6,167 3,3' -Dimthoxybenzidine (o-Dianisidine) 4,41 para-Dimthy lamoazobenzene 8,125 para-Dimthy larnobezenediazo scxium sulphonate 8,147 trans- 2 ( (Dimthy larno) rnthy lirno J - 5- (2- (5-ni tro- 2-furl)vinylJ-l, 3, 4-oxadiazole 7,147 3,3' -Dimthylbnzidine (o-Tolidine) 1,87 Dimthylcarbayl chloride 12,77 1,1 -Dimthy lhydrazine 4,137 l, 2-Dimthy lhydrazine 4,145 (corr. 7,320) Dimthyl sulphate 4,271 Dini trosopetathy lenetetrarne 11,241 1,4-Dioxae 11,247 Disulfiram 12,85 Dulcin 12,97 Endrin s-, 157 Epichlorohydrin 11,131 1 -Epxyethy 1-3, 4-epoxycyclohexane 11,141 3, 4-Epxy-6-rnthy lcyclohexy 1mthy 1 - 3, 4-epoxy- 6-rnthy lcyclohexane carboxy late 11 , 147 cis-9,10-Epxystearic acid 11 , 153 Ethiny loestradiol 6,77 Ethylene oxide 11,157 Ethylene sulphide 11 , 257 Etylenethourea 7,45 Ethy 1 rnthesulphonate 7,245 Ethy 1 selenc 12 , 107 Ethy 1 tellurac 12 , 115 Ethyniol diacetate 6,173 Evan blue 8,151 Ferba 12,121 2- (2-Formlhydrazino) -4- (5-nitro-2-furl) thiazole 7,151 (corr. 11,295)

277 Fuarenon-X 11,169

Glycidadehyde Il , 1 75 Glycidyl oleate Il,183 Glycidyl steaate Il,187 Griseoful vin 10,153 Haemtite 1,29 Heptachlor and its epoxide 5,173 Hydrazin 4,127 4-Hydroxyazobezene 8,157 Hydroxyserkine 10,265 Inden(l, 2, 3-cd)pyrene 3,229 Iron-dexan calex 2,161 Iron-dexrin calex 2,161 (corr . 2-,319) Iron oxide 1,29 Iron sorbitol-ci tric acid calex 2,161 Isatidie 10,269 Isonicotinc acid hydrazide 4,159 Isosafrole 1,169 Jacobine 10,275 Lasiocarine 10,281 Lead sal ts 1,40 (corr . 2,319) (corr . ~, 349) red acetate red arsete Le cabonate red phosphate I.ad subcetate I.te 12,131 Lidae 5,47 Luteoskyin 10 , 163 Magenta 4,57 (corr. 7,320) Maleic hydrazide 4,173 Maeb 12,137 Maortie (diydrocloride) 9,157

278 Medphalan 9,167 Meoxyrogterone acetate 6,157 Melphalan 9,167 Merphalan 9,167 Mestranol 6,87 Methoxychlor 5,193 2-Methy laziridine 9,61 Methylazoxythl acetate 1,164 Methyl carbamte 12 , 151 N-Methy 1 -N, 4-dini trosoailine 1,141 4,4' -Methylene bis (2-chloroailine) 4,65 1 4 ,4' -Methylene bis (2-rnthy laniline) 4,73 4 ,4' -Methy lenedianiline 4,79 (corr. 7,320) Methyl rnthanesulphonate 7,25,) N-Methy 1 -N' -ni tro-N-ni trosoganidine 4,183 Methy 1 red 8,161 Methy 1 selenac 12 , 161

Methy 1 thiouracil 7,53 Hirex 5,203 Mitomcin C 10 , 1 71 Monocrotaline 10 , 291 tbnuron 12 , 167 5- (!-rpholinomthyl) -3- ( (5-nitrofurfurlidene)- arno) - 2-oxazolidinone 7,161 Mustad gas 9,181 1 -Naphthy lame 4,87 (corr . 8,349) 2-Naphthylame 4,97 Native carrageenas 10 , 181 (cnrr. 11,295) Nickel and nickel comunds 2,126 (cnrr. 7,319) 11,75 Nickel acetate Nickel carbonate Nickel carbony 1 Nickelocne Nickel oxide

279 Nickel paer Nickel subsulphide Nickel sulphate 4-Ni trobipheny 1 4,113 5-Ni tro- 2-furaldehyde sercarbazone 7,171 1 (5-Ni trofurfur lidene) amno J - 2- irdazolidinone 7,181 N- (4- (5-Nitro-2-furl) -2-thiazolylJacetamde 1,181 7,185 Nitrogen ITstard (hydrochloride) 9,193 Ni trogen mustad N-oxide (hydrochloride) 9,209 N-Ni trosodi -n-buty lamne 4,197 N-Ni trosodiethy lamne 1,107 (CXrr. 11,295) N-Ni trosodirthy lamne 1,95 N-Ni trosoethy lurea 1,135 N-Ni trosonethy lurea 1,125 N-Ni troso-N-rnthy lurethane 4,211 N'rethisterone 6,179 Norethisterone acetate 6,179 Norethynodel 6,191

N'rges tre 1 6,201 Ochratoxin A 10 , 1 91 Oestradiol-17ß 6,99

Oestradiol mus tard 9,217

Oes trio 1 6,117 Oestrone 6,123 Oil Orange SS 8,165 Orange L 8,173 Orange G 8,181 Parasorbic acid 10,199 (corr . 12,271) Patulin 10,205 Penicillic acid 10,211 Phenicarbazide 12 , 1 77 Phenoxybenzamne (hydrochloride) 9,223 Polychlorinated biphenyls 7 ,261

280 Ponceau :M 8,78.9 Ponceau 3R 8,199 Ponceau SX 8,207 Potassium bis (2-hydroxyethyl) dithiocarbamte 12 , 183 Progesterone 6,135 1 , 3-Propane sul tone 4,253 Propham 12 , 189 ß-Propiolactone 4,259 n-Propyl carbate 12 , 201 Propy lene oxide 11 , 191 Propy 1 thiouracil 7,67 Quintozene (Pentachloroni trobenzene) 5,211 Reserpine 10,217 Retrorsine 10,30.3 Riddelliine 10 , 31 .3 Saccharated iron oxide 2,161 Safrole 1,169 10,231 Scar let red 8,217 Selenium and selenium cornunds 9,245 (corr. 12,271) Semcarbazide (hydrochloride) 12,209 Seneciphy lline 10,319 Senkirkine 10 , 327 Soium diethyldithiocarbate 12 , 21 7 Soot, tars and shale oils 3,22 Sterigmtocstin 1,175 10,245 Streptozotocin 4,221 Styrene oxide 11,201 Sudan L 8,225 Sudan II 8,233 Sudan III 8,241 Sudan brow RR 8,249 Sudan red 7B 8,253

281 Sunset yella. FCF 8,26 ;; Tanic acid 10,253 Tanins 10,254 Terpne polychlorinates (Strobae (B) 5,219 Testosterone 6,209 Tetraethy llead 2,150

Te t ram thy llead 2,150 Thiæ.cetade 7,77 Thiouracil 7,85 Thiourea 7,95 Thirar 12 ,225 Trichloroethy lene 11 , 263 Trichlorotriethy lamne hydrochloride 9,229 Triethylene glycol diglycidyl ether 11,209 Tris (aziridinyl) -para-benzoqinone 9,67 Tris (l-aziridinyl)phosphine oxide 9,75 Tris (l-aziridinyl)phosphine sulphide 9,85 2, 4 , 6-Tris (1 -aziridiny 1) -s-triazine 9,95 Tris (2-rnthyl - 1 -aziridinyl) phosphine oxide 9,107 Tryan blue 8,267 Uracil rnstad 9,235 Urethane 7,111 Viny 1 chloride 7 , 291 4-Viny lcyclohexene 11 1 277 Yellow AB 8,279 Yellaw OB 8,287 Zectran 12 , 2:5 ? Zineb 12,245 Ziram 12 , 259

282