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Home , Ammonium perchlorate, Chloride, Perchlorate, Perchloric acid, Potassium perchlorate, Sodium perchlorate

Technical Fact Sheet – January 2014

TECHNICAL FACT SHEET – PERCHLORATE

Introduction At a Glance This fact sheet, developed by the U.S. Environmental Protection Agency (EPA) Federal Facilities Restoration and Reuse Office (FFRRO),  White crystalline solid or colorless provides a summary of the contaminant perchlorate, including physical and chemical properties; environmental and health impacts; existing liquid. federal and state guidelines; detection and treatment methods; and  Both naturally occurring and man- additional sources of information. This fact sheet provides basic made anion. information on perchlorate to site managers and other field personnel who are addressing perchlorate contamination at cleanup sites or in  Sampling at current federal sites as drinking water supplies. as at Formerly Used Defense Perchlorate is a persistent contaminant of concern that has presented a Sites detected perchlorate primarily number of issues to the government, the private sector and other in association with sites historically organizations and interested parties. These issues include health effects involved in the manufacture, and risks, regulatory standards and cleanup levels, degradation processes and treatment technologies (EPA FFRRO 2005). maintenance, use and disposal of ammunition and rocket fuel. What is perchlorate?  Highly soluble in water; migrates  Perchlorate is a naturally occurring and man-made anion that quickly from soil to . - consists of one bonded to four (ClO4 )  Primary pathways for human (EPA FFRRO 2005; ITRC 2005). exposure include ingestion of  Perchlorate may occur naturally, particularly in arid regions such as contaminated food and drinking the southwestern United States (Rao and others 2007). water.  Manufactured forms of perchlorate include perchloric and  Short-term exposure to high doses such as perchlorate, perchlorate and perchlorate (EPA FFRRO 2005; ITRC 2005). may cause eye and skin irritation, coughing, nausea, vomiting and  Perchlorate is found as a natural impurity in salts from Chile, which are imported and used to produce nitrate fertilizers and other . products (EPA FFRRO 2005; ITRC 2005).  Health-based goals or drinking  Perchlorate is commonly used as an oxidizer in solid , water standards developed by munitions, , initiators for vehicles, matches and various states. signal flares (EPA FFRRO 2005; ITRC 2005). It is also used in some electroplating operations and found in some disinfectants and  Various detection methods herbicides (ATSDR 2008; ITRC 2005). available include chromatography, liquid chromatography, mass spectroscopy and electrospray

ionization. Disclaimer: The U.S. EPA prepared this fact sheet from publically-available  Common treatment technologies sources; additional information can be obtained from the source documents. This fact sheet is not intended to be used as a primary source of information and is not include ion exchange, bioreactors intended, nor can it be relied upon, to create any rights enforceable by any party and in situ . in litigation with the United States. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.

United States Office of Solid Waste and EPA 505-F-14-003 Environmental Protection Agency Emergency Response (5106P) January 2014 1 Technical Fact Sheet – Perchlorate

What is perchlorate? (continued)  Of the domestically produced (high grade)  Perchlorate has been used by the U.S. perchlorate, 90 percent is manufactured for use Department of Defense (DoD) as an oxidizer in in the defense and aerospace industries, munitions and missiles since the 1940s (EPA primarily in the form of FFRRO 2005; ITRC 2005). (GAO 2005; ITRC 2005).

Exhibit 1: Physical and Chemical Properties of Perchlorate Compounds (ATSDR 2008; EPA FFRRO 2005; ITRC 2005; NIH 2013; NIOSH 2013)

Ammonium Sodium Potassium Property Perchlorate Perchlorate Perchlorate Chemical Abstracts 7790-98-9 7601-89-0 7778-74-7 7601-90-3 Service (CAS) Numbers Colorless Physical Description White orthorhombic White orthorhombic orthorhombic crystal (physical state at room Colorless, oily liquid crystal deliquescent crystal or white crystalline temperature) powder Molecular weight 117.49 122.44 138.55 100.47 (g/mol) Water (g/L at o 200 2,096 15 Miscible in cold water 25 C) Melting / Boiling point* : > 200 Melting Point: 471 to Melting Point: 400 to Melting Point: -112 o ( C) (Decomposes) 482 525 Boiling Point: 19 Vapor pressure at 25oC Very low Very low Very low 6.8 (mm Hg) Specific gravity (g/cm3) 1.95 2.52 2.53 1.77 Octanol-water partition -5.84 -7.18 -7.18 -4.63 coefficient (log Kow) *Different melting point temperatures are identified in literature. Abbreviations: g/mol – grams per mole; g/L – grams per liter; oC – degrees Celsius; mm Hg – millimeters of mercury; g/cm3 – grams per cubic centimeter.

What are the environmental impacts of perchlorate?  Perchlorate is highly soluble in water, and perchlorate is manufactured or used as a reagent relatively stable and mobile in surface and during operations (ATSDR 2008; ITRC 2005). subsurface aqueous systems. As a result,  Types of military and defense-related facilities with perchlorate plumes in groundwater can be known releases include missile ranges and missile extensive. For example, the perchlorate plume at and rocket manufacturing facilities. However, a former safety flare site (the Olin Flare Facility) in since site-specific documentation may not be Morgan Hill, California, extends more than 9 miles available and based on historical uncertainties, it (EPA 2011; ITRC 2005). is generally difficult to identify specific military sites  Because of their low vapor pressure, perchlorate with known perchlorate releases. From 1997 to compounds and the perchlorate anion do not 2009, the Department of Defense reported volatilize from water or soil surfaces to air (ATSDR perchlorate detections at 284 (almost 70 percent) 2008; ITRC 2005). of its installations sampled (GAO 2010; ITRC  Perchlorate released directly to the atmosphere is 2005). expected to readily settle through wet or dry  In addition, the past disposal of munitions in either deposition (ATSDR 2008). burial pits or by open burning and open detonation  High concentrations of perchlorate have been may have resulted in releases to the environment. detected primarily at current and Formerly Used The amount of perchlorate released can vary Defense Sites historically involved in the depending on the length of time the disposal area manufacture, testing and disposal of ammunition was used and the types of munitions disposed of and rocket fuel or at industrial sites where in the area (ITRC 2005).

2 Technical Fact Sheet – Perchlorate

What are the environmental impacts of perchlorate? (continued)  Studies have shown perchlorate accumulates in private and federal facilities in 45 states, three some food crop leaves, tobacco plants and in U.S. territories and Washington D.C. The broad-leaf plants (ATSDR 2008). maximum concentrations reported in any media  Surveys conducted by the U.S. Food and Drug ranged from less than 4 parts per billion (ppb) to Administration have detected perchlorate in food more than 500,000 ppb (ASTSWMO 2011; GAO crops and milk (FDA 2008). 2010).  As of October 2009, perchlorate had been  EPA reported perchlorate detections at more than detected at varying levels in drinking water, 40 hazardous waste sites on the EPA National groundwater, surface water, soil or sediment at Priorities List as of June 2010 (GAO 2010).

What are the routes of exposure and the health effects of perchlorate?  Primary pathways for human exposure to and thyroperoxidase (TPO), which are involved in perchlorate are ingestion of contaminated food the biosynthesis of hormones (Wu and and drinking water (ATSDR 2008; EPA FFRRO others 2012). 2005).  was historically used to  Perchlorate is readily adsorbed after oral exposure treat and Graves’ Disease (an and can migrate from the stomach and intestines autoimmune disorder) because of its ability to to the bloodstream (ATSDR 2008). inhibit thyroid uptake (ATSDR 2008; NAS  The thyroid gland is the primary target of 2005). perchlorate toxicity in humans.  Studies conducted on rodents showed that play an important role in regulating perchlorate concentrations below that required to and are critical for normal growth and alter thyroid hormone equilibrium are unlikely to development in , infants and young cause thyroid cancer in human beings (ATSDR children. Perchlorate can interfere with iodide 2008; EPA IRIS 2005). uptake into the thyroid gland at high enough  Short-term exposure to high doses of ammonium, exposures, disrupting the functions of the thyroid sodium or potassium perchlorate may cause eye, and potentially leading to a reduction in the skin and respiratory tract irritation, coughing, production of thyroid hormones (ATSDR 2008; nausea, vomiting and diarrhea. Perchloric acid is Cal/EPA 2012; NAS 2005). corrosive to the eyes, skin and respiratory tract,  Study results indicate that exposure to high doses and short-term exposure to high doses may cause of perchlorate can result in the decrease of body sore throat, coughing, labored breathing, deep weight, cause hypertrophy of the thyroid gland and burns, loss of vision, abdominal pain, vomiting or decrease gene expression of (Tg) diarrhea (NIOSH 2013). Are there any federal and state guidelines and health standards for perchlorate?  The EPA assigned perchlorate a chronic oral adverse noncarcinogenic effects for a lifetime of reference dose (RfD) of 0.0007 milligrams per exposure (EPA 2009, 2012a). kilogram per day (mg/kg/day) (EPA IRIS 2005).  EPA has calculated a residential soil screening  The Agency for Toxic Substances and Disease level (SSL) of 55 milligrams per kilogram (mg/kg) Registry (ATSDR) has established a minimal risk and an industrial SSL of 720 mg/kg for perchlorate level (MRL) of 0.0007 mg/kg/day for chronic- and perchlorate salts (ammonium, potassium, duration oral exposure (365 days or more) to sodium and lithium) (EPA 2013). 1 perchlorate (ATSDR 2008, 2013).  EPA has decided to regulate perchlorate under the . EPA has initiated the process of proposing a national primary drinking

water regulation (EPA 2012b). 1 Screening Levels are developed using risk assessment guidance  The EPA established an Interim Lifetime Drinking from the EPA program. These risk-based concentrations Water Health Advisory of 15 micrograms per liter are derived from standardized equations combining exposure (µg/L), which is a concentration of a perchlorate in information assumptions with EPA toxicity data. These calculated screening levels are generic and not enforceable cleanup standards drinking water that is not expected to cause any but provide a useful gauge of relative toxicity. 3 Technical Fact Sheet – Perchlorate

Are there any federal and state guidelines and health standards for perchlorate? (continued)  EPA calculated a tap water screening level of 11 perchlorate in drinking water (CDPH 2012; µg/L for perchlorate and perchlorate salts (EPA DEP 2006). 2013).  California EPA released Draft California Human  The EPA Office of Solid Waste and Emergency Health Screening Levels (CHHSLs) for Response (OSWER) recommended a preliminary perchlorate. The draft CHHSLs for perchlorate in remediation goal (PRG) of 15 µg/L at Superfund soil are 28 mg/kg for residential property and 350 sites (where there is an actual or potential drinking mg/kg for commercial/industrial property (Cal/EPA water exposure pathway), where no federal or 2010). state applicable or relevant and appropriate  In 2012, California EPA’s Office of Environmental requirements exist under federal or state laws. Health Hazard Assessment (OEHHA) proposed to PRGs are developed based on readily available revise the existing Public Health Goal for information and are modified, as necessary, perchlorate in drinking water from 6 µg/L to 1 µg/L before final cleanup goals are established, based (Cal/EPA 2012). on information that becomes available during the  At least 10 other states have also developed remedial investigation/feasibility study (EPA 2009). advisory levels or health-based goals for  Numerous states have promulgated enforceable perchlorate, ranging from 1 to 18 µg/L for drinking standards for perchlorate in drinking water. For water and 1 to 72 µg/L for groundwater (GAO example, Massachusetts (2 µg/L) and California (6 2010). µg/L) have established enforceable standards for

What detection and site characterization methods are available for perchlorate?  The following methods can be used to analyze  The following methods can be used to analyze perchlorate in drinking water, groundwater, perchlorate in surface water, groundwater, surface water and irrigation water: wastewater, water and soil: . EPA Method 314.0 - Ion Chromatography (EPA . EPA SW-846 Method 6850 - High Performance OGWDW 2012). Liquid Chromatography/Electrospray . EPA Method 314.1 Rev 1.0 - Inline Column Ionization/ (EPA 2007a). Concentration/Matrix Elimination Ion . EPA SW-846 Method 6860 - Ion Chromatography with Suppressed Conductivity Chromatography/Electrospray Ionization/Mass Detection (EPA OGWDW 2012). Spectrometry (EPA 2007b). . EPA Method 314.2 - Two-Dimensional Ion  The presence of high amounts of other anions, Chromatography with Suppressed Conductivity such as , sulfate or carbonate, may Detection (EPA OGWDW 2012). interfere with the analysis of perchlorate (EPA . EPA Method 331.0 Rev. 1.0 - Liquid 1999). Chromatography/Electrospray Ionization/ Mass  Researchers have demonstrated the ability to Spectrometry (EPA OGWDW 2012). distinguish man-made and natural sources of . EPA Method 332.0 - Ion Chromatography with perchlorate in water samples using chlorine and Suppressed Conductivity and Electrospray oxygen stable ratio analysis (Bŏhlke and Ionization/Mass Spectrometry (EPA FFRRO others 2005; ITRC 2005). 2005). What technologies are being used to treat perchlorate?  Ex Situ Treatment electrically switched ion exchange system using . Ion exchange using perchlorate-selective or a conductive carbon nanotube nanocomposite nitrite-specific resins is a proven method for material could be used for the large-scale removal of perchlorate from drinking water, treatment of wastewater (ITRC 2008; DoD groundwater, surface water and other media. SERDP 2011). Laboratory-study results indicate that an

4 Technical Fact Sheet – Perchlorate

What technologies are being used to treat perchlorate? (continued) . A recent field study demonstrated the effective study demonstration results indicate that a reduction of perchlorate to below detection limits horizontal flow treatment well system can in groundwater using a large-scale weak effectively deliver electron donor and promote anion resin ion exchange system (DoD ESTCP the in situ biological reduction of perchlorate in 2012b). groundwater (DoD ESTCP 2009c). . A fluidized bed biological reactor (FBR) . A field study evaluated the use of gaseous treatment train successfully treated low and high electron donor injection technology for the concentration levels of perchlorate in anaerobic biodegradation of perchlorate in groundwater to meet the California drinking vadose zone soil. Results showed an average water standards (6 µg/L) in a field study (DoD perchlorate destruction of more than 90 percent ESTCP 2009b). within the targeted 10-foot radius of influence . Membrane technologies including within five months (DoD ESTCP 2009d). , and . A field study evaluated the use of an emulsified nanofiltration/ultrafiltration have been used to oil biobarrier to enhance the in situ anaerobic remove perchlorate from groundwater, surface biodegradation of perchlorate in groundwater. water and wastewater; however, these all Within 5 days of injection, perchlorate was require subsequent disposal of the perchlorate degraded from an initial concentration range of removed (EPA FFRRO 2005; ITRC 2008). 3,100 to 20,000 µg/L to below detection limits . Liquid phase carbon adsorption using granular (less than 4 µg/L) in the injection and nearby activated carbon (GAC) is used to remove low monitoring (DoD SERDP 2008). levels of perchlorate from groundwater and . A field study demonstrated the effective use of surface water. The adsorptive capacity of GAC an active biobarrier approach involving on-going may be increased through the addition of a groundwater recirculation and delivery of an surface-active coating to produce a modified or electron donor and a semi-passive approach tailored GAC (Hou and others 2013; ITRC involving the periodic delivery of electron donor 2008). to create a biobarrier and promote perchlorate . Laboratory study results indicate that ultraviolet biodegradation in groundwater (DoD ESTCP laser reduction can be used to decompose low 2009a, 2012a). levels of perchlorate (below 100 µg/L) dissolved . Laboratory and field studies have demonstrated in water. This technology is currently undergoing the potential for using monitored natural laboratory testing and has not yet been attenuation to treat perchlorate in groundwater commercialized or used in full-scale systems (DoD ESTCP 2010). (ITRC 2008; Vellanki and others 2013). . Several bench-scale tests have demonstrated  In Situ Treatment the potential effectiveness of . Enhanced in situ bioremediation using and constructed wetlands to treat perchlorate- perchlorate-selective microbes can be an contaminated media; limited field study effective method for degrading perchlorate in demonstrations have been implemented. Recent groundwater and soil. Study results indicate that laboratory study results indicate that the wetland acetate and addition as electron donor plant, Eichhornia crassipes, may be an effective can increase perchlorate removal efficiency plant for constructing a wetland to remediate (ITRC 2008; Wang and others 2013). high levels of perchlorate in water based on its high tolerance and accumulation ability (He and . Recent field studies have evaluated in situ others 2013; ITRC 2008). bioremediation of perchlorate in groundwater and soil using gaseous electron donors. Field

Where can I find more information about perchlorate?  Agency for Toxic Substances and Disease  Association of State and Territorial Solid Waste Registry (ATSDR). 2008. “Toxicological Profile Management Officials (ASTSWMO). 2011. for .” “Perchlorate Policy Update.” www.atsdr.cdc.gov/toxprofiles/tp162.pdf www.astswmo.org/Files/Policies_and_Publicatio  ATSDR. 2013. “Minimal Risk Levels (MRL)” List. ns/Federal_Facilities/2011.04_FINAL_Perchlorat www.atsdr.cdc.gov/mrls/index.asp e_Policy_Update.pdf

5 Technical Fact Sheet – Perchlorate Where can I find more information about perchlorate? (continued)  Bŏhlke, J. K., Sturchio, N.C., Gu, B., Horita, J., Safety Cards (ICSC). Brown, G.M., Jackson, W.A., Batista, J., and www.cdc.gov/niosh/ipcs/icstart.html P.B. Hatzinger. 2005. “Perchlorate Isotope  Rao, B., Anderson, T.A., Orris, G.J., Rainwater, Forensics.” Analytical Chemistry. Volume 77. K.A., Rajagopalan, S., Sandvig, R.M., Scanlon, Pages 7838 to 7842. http://denix.osd.mil/cmrmd/ B.R., Stonestrom, D.A., Walvoord, M.A, and W.A. upload/BOHLKE2005_0.pdf Jackson. 2007. “Widespread Natural Perchlorate  California Department of Public Health (CDPH). in Unsaturated Zones of the Southwest United 2012. Perchlorate in Drinking Water. States.” Environmental Science & Technology. www.cdph.ca.gov/certlic/drinkingwater/Pages/Pe Volume 41 (13). Pages 4522 to 4528. rchlorate.aspx  U.S. Department of Defense (DoD) Environmental  California Environmental Protection Agency Security Technology Certification Program (Cal/EPA). 2010. “California Human Health (ESTCP). 2009a. “Comparative Demonstration of Screening Levels for Perchlorate.” http://oehha. Active and Semi-Passive In-Situ Bioremediation ca.gov/risk/pdf/Perchlorate092310.pdf Approaches for Perchlorate Impacted  Cal/EPA. 2012. “Draft Public Health Goal for Groundwater (Longhorn Army Ammunition Plant).” Perchlorate in Drinking Water.” http://oehha.ca. ER-0219. gov/water/phg/pdf/120612Perchloratedraft.pdf  DoD. ESTCP. 2009b. “Demonstration of a Full-  He, H., Gao, H., Chen, G., Li, H., Lin, H. and Z. Scale Fluidized Bed Bioreactor for the Treatment Shu. 2013. “Effects of Perchlorate on Growth of of Perchlorate at Low Concentration in Four Wetland Plants and its Accumulation in Groundwater.” ER-0543. Plant Tissues.” Environmental Science and  DoD ESTCP. 2009c. “In Situ Bioremediation of Pollution Research. Volume 20 (10). Pages Perchlorate in Groundwater.” ER-0224. 7301 to 7308. www.cluin.org/download/contaminantfocus/perchlo  Hou, P., Cannon, F.S., Brown, N.R., Byrne, T., rate/ER-0224-C&P-1.pdf Gu, X., and C.N. Delgado. 2013. “Granular  DoD ESTCP. 2009d. “In Situ Bioremediation of Activated Carbon Anchored with Quaternary Perchlorate in Vadose Zone Soil Using Gaseous Ammonium/Epoxide-Forming Compounds to Electron Donors.” ER-0511. Enhance Perchlorate Removal from www.clu-in.org/download/contaminantfocus/ Groundwater.” Carbon. Volume 53. Pages 197 perchlorate/ER-0511-FR-1.pdf to 207.  DoD ESTCP. 2010. “Evaluation of Potential for  Interstate Technology Regulatory Council Monitored Natural Attenuation of Perchlorate in (ITRC). 2005. “Perchlorate: Overview of Issues, Groundwater (Indian Head).” ER-200428. Status, and Remedial Options.” www.serdp.org/Program-Areas/Environmental- www.itrcweb.org/Documents/PERC-1.pdf Restoration/Contaminated-Groundwater/  ITRC. 2008. “Remediation Technologies for Emerging-Issues/ER-200428 Perchlorate Contamination in Water and Soil.”  DoD ESTCP. 2012a. “Comparative Demonstration www.itrcweb.org/Guidance/GetDocument?docu of Active and Semi-Passive In-Situ Bioremediation mentID=61 Approaches for Perchlorate Impacted  Massachusetts Department of Environmental Groundwater: Active In Situ Bioremediation Protection (DEP). 2006. Water Resources: Demonstration (Aeroject Facility).” ER-200219. Perchlorate Information.  DoD ESTCP. 2012b. “Demonstration of www.mass.gov/eea/agencies/massdep/water/dri Regenerable, Large-Scale Ion Exchange System nking/perchlorate-information.html Using WBA Resin in Rialto, Ca.” ER-201168.  National Institute of Health (NIH). 2013. Haz-  DoD Strategic Environmental Research and Map: Information on Hazardous Chemicals and Development Program (SERDP). 2008. Occupational Diseases. “Development of Permeable Reactive Barriers http://hazmap.nlm.nih.gov/index.php (PRB) Using Edible Oils.” ER-1205.  National Research Council of the National  DoD SERDP. 2011. “Novel Electrochemical Academies (NAS). 2005. “Health Implications of Process for Treatment of Perchlorate in Waste Perchlorate Ingestion.” Water.” ER-1433. www.serdp.org/Program- www.nap.edu/catalog.php?record_id=11202 Areas/Environmental-Restoration/Contaminants-  National Institute for Occupational Safety and on-Ranges/ER-1433 Health (NIOSH). 2013. International Chemical

6 Technical Fact Sheet – Perchlorate

Where can I find more information about perchlorate? (continued)  U.S. Environmental Protection Agency (EPA).  EPA. Integrated Risk Information System (IRIS). 1999. “Method 314.0 Determination of 2005. “Perchlorate and Perchlorate Salts.” Perchlorate in Drinking Water Using Ion www.epa.gov/iris/subst/1007.htm. Chromatography.” Revision 1.0. www.epa.gov/  EPA Office of Ground Water and Drinking Water ogwdw/methods/pdfs/methods/met314.pdf (OGWDW). 2012. “Analytical Methods  EPA. 2007a. Method 6850. “Perchlorate in Developed by the Office of Ground Water and Water, Soils and Solid Wastes Using High Drinking Water.” www.epa.gov/safewater/ Performance Liquid Chromatography/ methods/analyticalmethods_ogwdw.html Electrospray Ionization/Mass Spectrometry.”  U.S. Food and Drug Administration (FDA). 2008. www.epa.gov/epawaste/hazard/testmethods/pdf “US Food and Drug Administration’s Total Diet s/6850.pdf Study: Dietary Intake of Perchlorate and  EPA. 2007b. Method 6860. “Perchlorate in .” www.nature.com/jes/journal/v18/n6/ Water, Soils and Solid Wastes Using Ion pdf/7500648a.pdf Chromatography/Electrospray Ionization/Mass  U.S. Government Accountability Office (GAO). Spectrometry.” www.epa.gov/epawaste/hazard/ 2005. “Perchlorate: A System to Track testmethods/pdfs/6860.pdf Sampling and Cleanup Results is Needed.”  EPA. 2009. “Revised Assessment Guidance for GAO-05-462. Perchlorate.” www.epa.gov/fedfac/documents/ www.gao.gov/new.items/d05462.pdf perchlorate_memo_01-08-09.pdf  U.S. GAO. 2010. “Perchlorate: Occurrence is  EPA. 2011. Region 9. Perchlorate in the Pacific Widespread but at Varying Levels; Federal Southwest. www.epa.gov/region9/toxic/ Agencies Have Taken Some Actions to perchlorate/per_ca.html#olin Respond to and Lessen Releases.” GAO -10-  EPA. 2012a. “2012 Edition of the Drinking Water 769. www.gao.gov/assets/310/308652.pdf Standards and Health Advisories.” EPA 822-S-12-  Vellanki, B.P., Batchelor, B., and A. Abdel- 001. Wahab. 2013. “Advanced Reduction Processes:  EPA. 2012b. Drinking Water Contaminants. A New Class of Treatment Processes.” Unregulated. Perchlorate. water.epa.gov/drink/ Environmental Engineering Science. Volume 30 contaminants/unregulated/perchlorate.cfm (5). Pages 264 to 271.  EPA. 2013. Regional Screening Level (RSL)  Wang, R., Chen, M., Zhang, J.W., Liu, F., H.H. Summary Table. Chen. 2013. “Microbial Perchlorate Reduction in www.epa.gov/reg3hwmd/risk/human/rb- Groundwater with Different Electron Donors.” concentration_table/Generic_Tables/index.htm Applied Mechanics and Materials. Volume 295  EPA Federal Facilities Restoration and Reuse to 298. Pages 1402 to 1407. Office (FFRRO). 2005. “Perchlorate Treatment  Wu, F., Zhou, X., Zhang, R., Pan, M., and K.L. Technology Update – Federal Facilities Forum Peng. 2012. “The Effects of Ammonium Issue Paper.” EPA 542-R-05-015. Perchlorate on Thyroid and www.epa.gov/tio/download/remed/542-r-05- Thyroid-Specific Gene Expression in Rat.” 015.pdf Environmental Toxicology. Volume 27 (8). Pages 445 to 452. Additional information on perchlorate can be found at EPA’s www.cluin.org/perchlorate.

Contact Information If you have any questions or comments on this fact sheet, please contact: Mary Cooke, FFRRO, by phone at (703) 603-8712 or by email at [email protected].

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