UNITED STATESENVIRONMENTAL PROTECTIONAGENCY WASHINGTON, D.C. 20460
OFFICE OF CHEMICAL SAFETY AND POLLUTIONPREVENTION

September 14, 2012 MEMORANDUM SUBJECT: Ammonia and Ammonium Sulfate: Human HealthRegistration Review Scoping Document PCCode:005302,005601 DP Barcode: 404903,401474 DecisionNo.: NA RegistrationNo.: NA PetitionNo.: NA Regulatory Action: Registration Review Risk Assess Type: Single Chemical Case No.: 7440, 5073 TXRNo.:NA MRIDNo.: NA



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TO: CAS No.: 7664-41-7, 7783-20-2 40CFR: NA

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# ~6~ Ttmothy C. Dole, CIH,**Industna Hygt**  I 

# 7 Jenny Tao, Senior Toxicologist

- · William Hazel, Ph.D., Senior Cll mist

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# / Risk Assessment and Science Support

### Bran~t**~s'si3Jf"** Antimicrobials Division (751OP) Timothy Leighton, Senior Scientist /-

# ~ Risk Assessment and Science Support Branch (RASSB) Antimicrobials Division (7510P) 

## /A 1 • 

## c/(//M! Steve Weiss, Acting Branch Chief

### 2J~ Risk Assessment and Science Support Branch (RASSB) Antimicrobials Division (751OP) Rebeccavon dem Hagen, Chemical Review Manager Regulatory Management Branch II (RMBII) Antimicrobials Division (751OP)

Page 1 of 11EXECUTIVE SUMMARY Ammonium sulfate is registered for papermills and industrial water systems. Itis used in conjunction with sodium hypochlorite (12.5 percent) in a closed systemto produce monochloramine. The specified dose onproduct labels is 1to 10 ppm available chlorine for both initial and subsequenttreatments. The toxicology database is consideredto be adequate for the currently registered uses and no additional studies are needed. Toxicity endpoints for ammonium sulfate have not been selected and quantitative risk assessments are not warranted. Based on its natural occurrence, being a human metabolite, history ofsafe use as a direct food additive, and due to the absence ofadverse effects in test animals athigh doses, there is no hazard expected from human exposure to ammonium sulfate from the registered uses. No dietary (food) risks are expectedto be associated with the existing uses. The onlypotentially toxic compound resulting inthe water system from the uses ofammonium sulfate is chloramine, however, any monochloramine not consumed inthe water system is expected to degrade under the high temperature conditions ofthe paper drying process (110° C) and it is not expected to remain inthe paperto migrate to food.
No drinking water risks are expected from the proposeduses ofammonium sulfate. Very low levels ofchloramine may survive to the point ofdischarge. EPA has established a maximum residual disinfectant level (MRDL) of4.0 ppm and water utilities are required to maintaintotal chloramines at orbelowthis MRDL. Given this limit, the fact that the maximum applicationrate is 10 ppm (for papermills) andthe fact thatmost ofthemonochloroamine will be consumed during the treatmentprocess, it is highly unlikely that drinking water exposures to chloramine will result in risks ofconcern. Occupational exposures are not anticipatedto result in any risks ofconcern for ammonium sulfate because ammonium sulfate is oflowtoxicity and itis handled in a closed system. Itis also understood thatthe reaction ofammonium sulfate withthe chlorine source is controlledto enhance the production ofmonochloramine, which is non-volatile, while minimizing the production oftrichloramine, which is volatile. Itis recommended that the conditions needed to preventthe production oftrichloramine be stated onthe label. Given the above, no toxicology or exposure data will be needed for registration review of ammonium sulfate. The Agency does not anticipate the need to conduct a quantitative human healthrisk assessment on ammonium sulfate.

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### 1.0 BACKGROUND INFORMATION 1.1 Product Types According to OPPIN, there are two products that list ammonia (PC Code 005302) as the active ingredient (ai) and two products that list ammonium sulfate (PC Code 005601) as the ai. These products are listed in Table 1.
Table 1 - Registered Products ContainingAmmonia and Ammonium Sulfate EPA Reg. Product Company Active IngredientListed Active Ingredient Number Name Name on Label

- PercentA.I. Expressed as PercentA.I. Ammonium Sulfate 9386-49 Fennosurf586 Kemira Ammonia (total) -7.59% Ammonium Sulfate- 28% 1706-240 Nalco 60620 Nalco Ammonium Sulfate- 20% Ammonium Sulfate- 20% 1448-433 Busan 1215 Buckman Ammonia (total) -7.59% Ammonium Sulfate- 28% 1448-432 BCMW Buckman Ammonia (total) -7.59% Ammonium Sulfate- 28% 

### 1.2 Summary ofRegistered Uses Ammonium sulfate is registered for papermill and industrial water system uses as listed inTable 2. Itis used in conjunction with sodium hypochlorite (12.5 percent) in a closed metered chemical feed system to produce monochloramine. The treatment can be administered using the slug, intermediate orcontinuous feed methods. The specified dose is 1to 10 ppm available chlorine for both initial and subsequenttreatments. Table2 -Ammonium SulfateAntimicrobialUses Use Application Rate _(Available Chlorine) Pulp and PaperMill Water Systems I to 10 ppm Industrial Cooling Towers lto5ppm Recirculating Cooling Water Systems lto5ppm Evaporative Condensers lto5ppm Influent water Systems lto5ppm Brewery and Food Pasteurizers lto5ppm Industrial Fresh Water Systems lto5ppm Seawater desalination and reverse osmosis systems lto5ppm Paintbooth sumps lto5ppm Decorative fountains and ponds used for coolingpurposes lto5ppm Sewage and wastewater systems 1to 5 ppm 

### 1.3 Chemical and PhysicalProperties The chemical andphysical properties ofammonium sulfate that are relevant for humanhealth risk assessment are listed in Table 3.

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### Table 3 - Chemical and Physical Properties ofAmmonium Sulfate Property Value Reference Molecular Formula CNH4)2S04 HSDB Molecular Weight 132 gm/mole HSDB Physical State Solid HSDB Melting Point 280 C (decomposes) HSDB Water Solubility 77.6 gm/100 gm H2 0 at25 C HSDB VaporPressure 1 x 10'22 mm Hg at25 C HSDB Henry's Law Constant 5.5 X 10'9 atm-m3/mole HSDB HSDB =Hazardous Substances Database (www.toxnet.nlm.nih.gov) 

### 2.0 TOXICOLOGY When ammonium sulfate was registered, the toxicology databases for ammonium sulfate and monochloramine were consideredto be adequate and no additional studies were required (EPA, 2011). No additional studies have been submitted by the registrants orpublished inthe open literature. The toxicity information for ammonium sulfate was taken mainly from the OECD SIDS Dossier for ammonium sulfate (SIDS, 2004) and is reviewedbythe agency inD401626 (EPA, 2012). The toxicology database for monochloramine has beenreviewedpreviously in D386325 (EPA, 2011b) and is discussed below. 

### 2.1 Acute Toxicity
The acute toxicity studies indicate that ammonium sulfate is oflow acute toxicity (i.e. toxicity category III or IV) by all routes ofadministration and is not a dermal sensitizer. 

### 2.2 Subchronic and ChronicToxicity ofAmmonium Sulfate Inhalation Study in

### Rats (Pepelko, et al, 1980) A 14-day inhalation study onrats is included in the SIDS Dossier for ammonia sulfate. During this study, 10 male rats were exposed to an ammonium sulfate aerosol for 8 hours/day at a concentration of300 mg/m3(count mean particle diameter: 1 - 2 f.!m). Arterial blood gases were measured after 1, 3, 7, and 14 days. Pulmonary function tests were performed after 14 days of exposure and histological examinations were performed at the end ofthe exposure period. The exposure did not result in any significant changes in lung morphology, lung volumes, and arterial blood gases. The histological examinations did not reveal any changes in the trachea, bronchial lymph nodes, and lungs and the exposure had no adverse effects on body weight. A NOAEL of300 mg/m3for toxicity to the lower respiratory tract can be deduced from the study. 

### Subchronic Oral Study in Rats (Takagi et al, 1999) A 13-weekoral toxicity study ofammonium sulfate was performed in F344 rats ofboth sexes by feeding them a CRF-1 powder diet containing concentrations ofO%, 0.39%, 0.75%, 1.5% and 3.0% ofthe substance. Rats were randomly divided into 5 groups each consisting of 10 males and 10 females. Male animals in the 3% group exhibited diarrhea during the administration period. No changes indicating obvious ammonium sulfate toxicity were observed inthe body weights, organweights, hematological, serum biochemical or histopathological examinations.
Page 4 of 11Based onthe results, the NOAEL ofammonimn sulfate wasjudgedto be 1.5% ofthe diet of males (866 mg/kg/day) and 3% offemales (1975 mg/kg/day). It was also determined thatthe maximmntolerated dose (to be used inthe 2-year carcinogenicity studies) was 3.0% ormore in the diet. Chronic Toxicity/Carcinogenicity Oral Study in Rats (Ota et al, 2006) Chronic toxicity and carcinogenicity studies ofammonimn sulfate were performed inmale and**fe~ale** Fisher 344 rats at dietary concentrations of0%, 0.1 %, 0.6% and 3% in a 52 week toxicity study and 0%, 1.5% and 3% in a 104 week (2 year) carcinogenicity study. Significant increases in kidney and/or liver weights were observed in males and females ofthe 3.0% diet group, butno effects were found on survival rate, body weights, and hematological, sermn biochemistry, or histological parameters at any dose levels inthe chronic study. Regarding carcinogenicity, no significant influence onthe incidences oftumors in any ofthe organs and tissues examined was observed. Itwas concludedthatthe NOAEL was 0.6% ofthe diet, which is equivalentto 256 and 284 mg/kg/day inmales and females, respectively, and thatthe compound is not carcinogenic under the conditions ofthe study. Metabolism Absorbed ammonimn ion is transported to the liver and ultimately incorporated innitrogenous waste compounds such as uric acid and urea and excreted inthe urine. Ammonimn ion is also an endogenous substance that serves a majorrole inthe maintenance ofthe acid-base balance. Minor amounts ofammonimn nitrogen are incorporated inthe physiologicalN-pool. Sulfate is a normal intermediate inthe metabolism ofendogenous sulfur compounds, and is excreted unchanged orin conjugated form in urine. Mutagenicity Ammonimn sulfate was notmutagenic to bacteria (Ames test) and yeasts with or without metabolic activation. Itdid not induce chromosomal aberrations inmammalian orhmnan cell cultures. No invivo genotoxicitytests are available. Based onthe negative results from in vitro studies and the negative results inthe in vivo micronucleus test using ammonimn chloride, mutagenic activity ofammonimn sulfate invivo is unlikely. Similarto other salts, high doses of ammonimn sulfate mayhave the capability oftmnorpromotion inthe rat stomach; itis, however, much less potentthan sodimn chloride when tested under identical conditions. Reproductive and Developmental Toxicity There are no reproductive and developmental toxicity studies for ammonimn sulfate inthe Agency's hazard database. As ammonimn sulfate dissociates into ammonimn (NH4+)and sulfate (S04 - 2) ions, studies with other ammonimn and sulfate salts, as analogues, available in the open literature andunpublished studies were included inthe SIDS Dossier (SIDS, 2004) and summarized below. Reproduction/Developmental Toxicity Screening Study (Fertilizer Institute, 2002) This study was performed according to OECD Test Guideline 422. Rats were administered diammonimnphosphate at dose levels of0, 250, 750, and 1500 mg/kg/day by gavage (animals were paired 2 weeks after start oftreatment). No mortality was reported, and no treatmentrelated signs ofclinical toxicity were observed. Some treatment-related effects onhematology

Page 5 of 11parameters were noticed atthe mid- and high-dose levels. Body weight gain was reduced temporarily inthe high-dose group. Banding ofthe enamel ofthe incisors ofthe parent animals were observed from the mid-dose group, which was likely due to the inhibiting effect of phosphate onmineralization ofthe teeth. There were no effects onthe offspring ofparents exposed to diarnmoniumphosphate. There were no effects onthe time to achieve conception and pregnancy length. Viability up to day 4 postpartum and macroscopic necropsy showed no effect onthe pups. The NOAEL for developmental toxicity was determined to be 1500 mg/kg/day One Generation Reproduction Study in Mice (Andres, et al, 1989). Female ICRmice were treated with sodium sulfate at doses of840, 2040, 4320, or 6560 mg/kg/day in drinking water from one weekpriorto breeding until study end (day 21 ofsecond parity). No treatment-related effects were found in litter size, litter weaning weights, or gestational or lactational weight gain ofthe dams. However, no fertility indices were measured nor were fetuses examinedhistopathologically. Developmental Study in Mice (Seidenberg et al, 1986) Aqueous sodium sulfate was administered by gavage to 28 pregnant ICRmice at a single dose of 2800 mg/kg/day from gestation days 8 through 12. The dose selected was at or near the dose level producing overt maternal toxicity inpreliminary range-finding studies with non-regnant animals. No macroscopic effects or adverse effects on body weight gain were detected in the pups, however, the pups were not examinedhistopathologically and the exposure period was short compared to a valid guideline study, therefore the study is oflimitedreliability. 2.3 Subchronic and Chronic Toxicity ofMonochloroamine Developmental/Reproductive Toxicity The developmental and reproductive toxicity ofmonochloramine has been examined in rats, but with suboptimal studies. However, due to the chemical relationship between monochloramine and chlorine, the Agency believes that the reproductive and developmental studies for chlorine may be used to satisfy these data gaps for monochloramine. The available studies do not indicate concerns for increased sensitivity ofthe fetus or offspring. Reproductive Study in Rats (Carlton et al., 1986) Chloramine was administered by gavage in water at doses ofO, 2.5, 5.0 and 10 mg/kg/day to male (12/dose group) and female (24/dose group) rats for a total of66-76 days. Males were treated for 56 days and females for 14 days prior to mating. Dosing continued during the 10- day mating period and afterward females were dosed with chloramine daily during gestation and lactation. Males were necropsied at the end ofthe mating period. Dams and some offspring were necropsied at 21 days after birth. Other offspring were dosed with chloramine after weaning until they were 28-40 days old. No statistical differences were observed between control and exposed rats in fertility, viability, litter size, day ofeye opening or average day ofvaginal patency. There were no alterations in sperm count, direct progressive sperm movement, percent mobility or sperm morphology in adult males. Weights ofmale and female reproductive organs were not significantly different among control and test groups, and there were no significant morbid anatomic changes evident on tissue examination. There were no signs oftoxicity, changes in blood counts, or effects on body weight in adult
Page 6 ofllrats ofeither sex at any dose level. The mean weight ofthe pups was not affected by chloramine treatment. A NOAEL of 10 mg/kg/day for reproductive effects can be defined from this study. 

### Developmental Studyin Rats (Abdel-Rahman, et al, 1982) Monochloramine was administered in the drinking water to female Sprague-Dawleyrats (6/dose group) at 0, 0.15, 1.5 and 15 mg/kg/day. Treatment did not increase the number of fetal resorptions or affect fetal weight nor did it induce soft-tissue anomalies or skeletal malformations. The developmental NOAEL is 15 mg mg/kg/day although confidence is low due to the small number ofanimals exposed. 

### Mutagenicity/Carcinogenicity Monochloramine is not classifiable as to human carcinogenicity (Group D) based on inadequate human data and equivocal evidence ofcarcinogenicity from animal bioassays. A two-year bioassay showed marginal increase in mononuclear cell leukemia in female F344/N rats. No evidence ofcarcinogenic activity was reported in male rats or male or female B6C3F1 mice. Genotoxicity studies, both 

### in vitro and 

### in vivo, gave negative results. 

### ChronicToxicity (NTP, 2002) The long-term effects ofchloraminated water were examined in F344/N rats and B6C3F1 mice. Groups ofrats (70/sex/dose) and mice (70/sex/dose) were administered chloraminated drinking water at 0 (controls), 50, 100 or 200 ppm for 103-104 weeks. Based on body weight and water consumption data provided in the study, the intake ofchloramine was 0, 2.6, 4.8, and 8.7 mg/kg/dayfor male rats; 0, 3.4, 5.3 and 9.5 mg/kg/dayfor female rats. Consumption ofchloramine in mice was 0, 5.0, 8.9, and 15.9 mg/kg/dayfor males; and 0, 4.9, 9.0, and 17.2 mg/kg/dayfor females. Interim sacrifices (10/sex/dose) were conducted at weeks 14 and 66. In both species, there were no statistically significant findings attributable to chemical exposure at the highest dose tested of200ppm. Based onthe study results, the NOAEL was determined to be 200 ppm, or 9.5 mg chloramines/kg/day for rats and 17.2 mg chloramines/kg/day for mice. 

### 3.0 DIETARYASSESSMENT 3.1 Dietary Exposure Dietary exposures to ammonium sulfate and monochloroamine were evaluated inD391302 (EPA, 2011a) which was written for the registration ofammonium sulfate as Nalco 60620. Ammonium sulfate products are mixed on site with sodium hypochlorite to form monochloramine which is used as a slimicide inpaper and paperboard water systems at a residual chlorine level of 1-10 ppm. Treatedpaper and paperboard may be used for food contact. Ammonium sulfate has low acute toxicity. Longer term mammalian dosing studies resulted in such low toxicitythat toxicity endpoints could notbe selected. The only potentiallytoxic compound resulting from ammonium sulfate uses in the water system is monochloramine. Any monochloramine not consumed inthe water system is expected to degrade under the high temperature conditions ofthe paper drying process (110 °C). Although only limited toxicity data are available onmonochloramine, it is not expected to remain in the paperto migrate to food. The chemical species likely to remain to be incorporated into the dried/finished paper and

Page 7 ofllpaperboard are ammonium ion, sulfate ion, nitrate ion, and chloride ion for whichthere are no dietary toxicity concerns. It is only these benign compounds that couldpotentiallymigrate into food from food-contact paper or paperboard. Therefore, no dietary (food) risks are expectedto be associated withthe proposed uses and a dietary risk assessment is not anticipated for this registration review. 

### 3.2 Drinking Water Exposure
No drinking water risks are expected from the proposed uses ofammonium sulfate. Very low levels ofmonochloramine may survive to the point ofdischarge. EPA has established a maximum residual disinfectant level (MRDL) of4.0 ppm and waterutilities are required to maintaintotal chloramines at or belowthis MRDL. Given this limit, the fact that the maximum applicationrate is 10 ppm (for papermills) and the fact that most ofthe monochloramine will be consumed during the treatmentprocess, itis highly unlikely that drinking water exposures to monochloramine will result inrisks ofconcern. 

### 4.0 OCCUPATIONAL AND RESIDENTIAL EXPOSURES Occupational exposures to ammonium sulfate and monochloroamine were evaluated in D391275 (EPA, 2011c) which was written for the registration ofammonium sulfate as Nalco 60620. The Agency determined that exposures were not anticipated to result in any risks of concern for ammonium sulfate because ammonium sulfate is oflowtoxicity and it is handled in a closed system. Itwas also anticipated that the reaction ofammonium sulfate with sodium hypochlorite would be controlledto enhance the production ofmonochloramine, which is nonvolatile, while minimizing the production oftrichloramine, which is volatile. Itwas recommended thatthe conditions needed to preventthe production oftrichloramine be stated on the label. Residential exposures are not anticipated for ammonium sulfate and monochloroamine because these products are only used in industrial areas. 

### 5.0 AGGREGATE AND CUMULATIVE EXPOSURE As there are no dietary (food or drinking water) or residential exposures associated withthe currently registered uses ofammonium sulfate there is no need to estimate aggregate risks. As discussed in D391302 (EPA, 2011a), it was assumed that, for the purposes ofthe section 3 registration action, that ammonium sulfate does not have a common mechanism oftoxicity with other substances largely because it elicits no adverse effects inmammals. No newdatahave become available that would change that assumption.



### 6.0 INCIDENTS There are nine human exposure incidents inthe OPP incident database that are associated with ammonia or ammonium sulfate. All ofthese incidents are classified as minor (HD). One of

Page 8 ofllthese incidents involves hand exposure to a spray adjuvant inert product, two involve foreign products that are notregistered inthe U.S. and six involve a currently registered antimicrobial product. No other information is included inthe incidentreports. 

### 7.0 TOLERANCES Residues ofammonium sulfate are exempted from the requirement ofa tolerance whenused as a solid diluent or carrier in accordance with good agricultural practices as inert (or occasionally active) ingredients inpesticide formulations applied to growing crops orto raw agricultural commodities after harvest (40 CFR 180.910). 

### 8.0 ENDOCRINE DISRUPTION EFFECTS
As required by FIFRA and FFDCA, EPAreviews numerous studies to assess potential adverse outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and chronic toxicity, including assessments ofcarcinogenicity, neurotoxicity, developmental, reproductive, and general or systemictoxicity. These studies include endpoints which may be susceptible to endocrine influence, including effects on endocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and chronic studies that assess growth, developmental and reproductive effects in different taxonomic groups. A humanhealthrisk assessment identifying the most sensitive endpoints has notbeen conducted for the ammonia/ammonium sulfate case. As required by FFDCA section 408(p), ammonia/ammonium sulfate is subjectto the endocrine screening part ofthe Endocrine Disruptor Screening Program (EDSP).
EPA has developed the EDSP to determine whether certain substances (including pesticide active and other ingredients) may have an effect inhumans orwildlife similarto an effect produced by a "naturally occurring estrogen, or other such endocrine effects as the Administrator may designate." The EDSP employs a two-tiered approachto making the statutorilyrequired determinations. Tier 1 consists ofa battery of 11 screening assays to identify the potential ofa chemical substance to interact withthe estrogen, androgen, or thyroid (E, A, or T) hormonal systems. Chemicals that go through Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceedto the next stage ofthe EDSP where EPA will determine which, ifany, oftheTier 2 tests are necessary based onthe available data. Tier 2 testing is designed to identify any adverse endocrine-related effects caused by the substance, and establish a dose-response relationship between the dose and the E, A, or T effect. Under FFDCA section408(p), the Agency must screen all pesticide chemicals. Between October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of67 chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. Ammonium sulfate is not among the group of58 pesticide active ingredients onthe initial listto be screened under the EDSP. For further information onthe status ofthe EDSP, the policies and procedures, the list of 67 chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our website: http:/ /www.epa.gov/endo/

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### 9.0 ANTICIPATED DATA NEEDS 9.1 Toxicology Studies
No additional studies are needed to assess the hazards ofammonium sulfate or monochloramine. 

### 9.2 Exposure Studies
No dietary or occupational andresidential exposure studies are needed to assess the antimicrobial uses ofammonium sulfate. 

### 10.0 REFERENCES Abdel-Rahman et al, 1982. Effect ofchlorine and monochloramine in drinking water on the developing rat fetus. Journal Applied Toxicology 2(3):156-9. (MRID 48865601) Andres CJ, Cline TR (1989). Influence ofsulfate in drinking water onmouse reproduction during two parities. Journal Animal Science 67, 1313-1317. (MRID 48865607) BASF AG, 1989. Department ofToxicology. Unpublished report (88/736). 26 June 1989. (Cited in SIDS, 2004) Carlton et al, 1986. Reproductive Effects ofAlternate Disinfectants. Environmental Health Perspectives 69:237-41. (MRID 48865602) FertilizerInstitute, 2002. Unpublished data. DAP 4-Week General Toxicity and Reproductive/Developmental Toxicity Screening Test. WBG 001/022948

. 20 November 2002 Litton Bionetics, 1975

. Mutagenic evaluation ofcompound FDA 73-42: Ammonium sulfate granular food grade. Submitted to the US Food and Drug Administration, 30 June 1975. National Technical Information Service PB 245-506. NTP, 1992. Toxicology and Carcinogenesis Studies ofChlorinated and Chloraminated Water (CAS Nos. 7782-50-5, 7681-52-9 and 10599-90-3) in F344/N Rats and B6C3F1 Mice (drinking water studies), NTP TR 392, National Toxicology Program, National Institutes of Health. 1992 Ota et al, 2006. Ota Y, HasumuraM, and OkamuraM, Chronic toxicity and carcinogenicity of dietary administered ammonium sulfate in F344 rats. Food Chern Toxicology. 2006 Jan;44(1):17-27. (MRID 48834401) Pepelko et al, 1980. Toxicology ofammonium sulfate in the lung. Bulletin Environmental Contamination Toxicology. 24, 156-160. (Cited in SIDS, 2004)

Page 10 of 11Seidenberg et al, 1986. Validation ofan in Vivo Developmental Toxicity Screen inthe Mouse. Teratogenesis, Carcinogenesis, and Mutagenesis 6, 361-374. (MRID 48865608- Cited in SIDS, 2004) SIDS, 2004. OECD SIDS Initial Assessment Report for SIAM 19 Ammonium Sulfate. BMU (Bundesministerium fiirUmwelt, Naturschutz und Reaktorsicherheit), 19-22 October 2004. Takagi et al, 1999. 13-week subchronic oral toxicity study ofammonium sulfate in rats [Abstract; article in Japanese]. Kokuritsu Iyakuhin ShokuhinEisei Kenkyusho Hokoku 1999;(117):108-14. (MRID 48865603- Cited in SIDS, 2004)
U.S. Environmental ProtectionAgency, 1987. Recommendations for and Documentation of Biological Values for Use inRisk Assessment. Preparedbythe Environmental Criteria and Assessment Office, Office ofHealth and Environmental Assessment, Cincinnati OH for the Office ofSolidWaste and Emergency Response, Washington, DC. EPA/600/6-87/008. NTIS PB88-179874/AS. US EPA, 2005. Integrated Risk Information System for Monochloramine. http:/www.epa.gov /iris/subst/0644.htrn. US EPA, 2011a. Nalco Co. ProposedRegistration ofNalco 60620 Slimicide Containing Ammonium Sulfate for Use inPaper andPaperboard Water Systems: Ecological and Human HealthRiskAssessments, D391302, 6/29/11. US EPA, 2011b. Hazard Assessment ofAmmonium Sulfate (Part 1) andMonochloramine (Part 2). D386325, 4/19/11. US EPA, 2011c. Occupational Exposure Assessment for the Proposed Use ofAmmonium Sulfate as Nalco 60620 in Pulp and Paper Mill Water Systems. D391275. 6/29/11 US EPA, 2012. Ammonium Sulfate: Summary ofMammalian Toxicology Data for the Registration Review Scoping Document. D401626.

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