Sulfentrazone; Pesticide Tolerances
Federal Register, Volume 77 Issue 134 (Thursday, July 12, 2012)
Federal Register Volume 77, Number 134 (Thursday, July 12, 2012)
Rules and Regulations
Pages 41081-41088
From the Federal Register Online via the Government Printing Office www.gpo.gov
FR Doc No: 2012-17020
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ENVIRONMENTAL PROTECTION AGENCY
EPA-HQ-OPP-2011-0758; FRL-9353-8
Sulfentrazone; Pesticide Tolerances
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes tolerances for residues of sulfentrazone in or on multiple commodities which are identified and discussed later in this document. Interregional Research Project Number 4 (IR-4) and FMC requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA).
DATES: This regulation is effective July 12, 2012. Objections and requests for hearings must be received on or before September 10, 2012, and must be filed in accordance with the instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).
ADDRESSES: The docket for this action, identified by docket identification (ID) number EPA-HQ-OPP-2011-0758 is available at http://www.regulations.gov or at the OPP Docket in the Environmental Protection Agency Docket Center (EPA/DC), located in EPA West, Rm. 3334, 1301 Constitution Ave. NW., Washington, DC 20460-0001. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the OPP Docket is (703) 305-5805. Please review the visitor instructions and additional information about the docket available at http://www.epa.gov/dockets.
FOR FURTHER INFORMATION CONTACT: Andrew Ertman, Registration Division (7505P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460-0001; telephone number: (703) 308-9367; email address: ertman.andrew@epa.gov.
SUPPLEMENTARY INFORMATION:
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General Information
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Does this action apply to me?
You may be potentially affected by this action if you are an agricultural producer, food manufacturer, or pesticide manufacturer. Potentially affected entities may include, but are not limited to those engaged in the following activities:
Crop production (NAICS code 111).
Animal production (NAICS code 112).
Food manufacturing (NAICS code 311).
Pesticide manufacturing (NAICS code 32532).
This listing is not intended to be exhaustive, but rather to provide a guide for readers regarding entities likely to be affected by this action. Other types of entities not listed in this unit could also be affected. The North American Industrial Classification System (NAICS) codes have been provided to assist you and others in determining whether this action might apply to certain entities. If you have any questions regarding the applicability of this action to a particular entity, consult the person listed under FOR FURTHER INFORMATION CONTACT.
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How can I get electronic access to other related information?
You may access a frequently updated electronic version of EPA's tolerance regulations at 40 CFR part 180 through the Government Printing Office's e-CFR site at http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?&c=ecfr&tpl=/ecfrbrowse/Title40/40tab_02.tpl.
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How can I file an objection or hearing request?
Under FFDCA section 408(g), 21 U.S.C. 346a, any person may file an objection to any aspect of this regulation and may also request a hearing on those objections. You must file your objection or request a hearing on this regulation in accordance with the instructions provided in 40 CFR part 178. To ensure proper receipt by EPA, you must identify docket ID number EPA-HQ-OPP-2011-0758 in the subject line on the first page of your submission. All objections and requests for a hearing must be in writing, and must be received by the Hearing Clerk on or before September 10, 2012. Addresses for mail and hand delivery of objections
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and hearing requests are provided in 40 CFR 178.25(b).
In addition to filing an objection or hearing request with the Hearing Clerk as described in 40 CFR part 178, please submit a copy of the filing that does not contain any CBI for inclusion in the public docket. Information not marked confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA without prior notice. Submit a copy of your non-CBI objection or hearing request, identified by docket ID number EPA-HQ-OPP-2011-0758, by one of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov. Follow the online instructions for submitting comments. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute.
Mail: OPP Docket, Environmental Protection Agency Docket Center (EPA/DC), Mail Code: 28221T, 1200 Pennsylvania Ave. NW., Washington, DC 20460-0001.
Hand Delivery: To make special arrangements for hand delivery or delivery of boxed information, please follow the instructions at http://www.epa.gov/dockets/contacts.htm.
Additional instructions on commenting or visiting the docket, along with more information about dockets generally, is available at http://www.epa.gov/dockets.
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Summary of Petitioned-For Tolerance
In the Federal Register of October 5, 2011 (76 FR 61647) (FRL-8890-
5), EPA issued a notice pursuant to FFDCA section 408(d)(3), 21 U.S.C. 346a(d)(3), announcing the filing of a pesticide petition (PP 1E7890) by (IR-4), Rutgers, The State University of New Jersey, 500 College Road East, Suite 201-W., Princeton, NJ 08540. The petition requested that 40 CFR 180.498 be amended by establishing tolerances for residues of the herbicide sulfentrazone (N-2,4-dichloro-5-4-(difluoromethyl)-
4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-
ylphenylmethanesulfonamide) and its metabolites 3-
hydroxymethylsulfentrazone (N-2,4-dichloro-5-4-(difluoromethyl)-4,5-
dihydro-3-hydroxymethyl-5-oxo-1H-1,2,4-triazol-1-
ylphenylmethanesulfonamide) and 3-desmethyl sulfentrazone (N-2,4-
dichloro-5-4-(difluoromethyl)-4,5-dihydro-5-oxo-1H-1,2,4-triazol-1-
ylphenylmethanesulfonamide), in or on rhubarb at 0.2 parts per million (ppm); turnip, roots at 0.2 ppm; turnip, tops at 0.7 ppm; and sunflower subgroup 20B at 0.2 ppm; ``Tolerances with regional registrations'' in or on wheat, forage at 0.45 ppm (Pacific Northwest only); wheat, hay at 0.20 ppm (Pacific Northwest only); wheat, grain at 0.20 ppm (Pacific Northwest only); wheat, straw at 1.4 ppm (Pacific Northwest only); and cowpea, succulent at 0.15 ppm (Tennessee only). In addition, the petition requested to amend the current tolerances in 40 CFR 180.498 in or on bean, lima, succulent at 0.15 ppm by removing the tolerance from the table in Section (a)(2) and adding the tolerance to Section (c) Tolerances with regional registrations. Upon approval of the aforementioned tolerance on the sunflower subgroup 20B, the petition additionally proposed to remove the established tolerance in or on the raw agricultural commodity sunflower, seed at 0.2 ppm. That notice referenced a summary of the petition prepared by FMC, the registrant, which is available in the docket, http://www.regulations.gov. There were no comments received in response to the notice of filing.
In the Federal Register of July 6, 2011 (76 FR 39358) (FRL-8875-6), EPA issued a notice pursuant to FFDCA section 408(d)(3), 21 U.S.C. 346a(d)(3), announcing the filing of a pesticide petition (PP 1F7838) by FMC Corporation, 1735 Market St., Philadelphia, PA 19103. The petition requested that 40 CFR 180.498 be amended by establishing tolerances for residues of the herbicide sulfentrazone (N-2,4-
dichloro-5-4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-
triazol-1-ylphenylmethanesulfonamide) and its metabolites 3-
hydroxymethylsulfentrazone (N-2,4-dichloro-5-4-(difluoromethyl)-4,5-
dihydro-3-hydroxymethyl-5-oxo-1H-1,2,4-triazol-1-
ylphenylmethanesulfonamide) and 3-desmethyl sulfentrazone (N-2,4-
dichloro-5-4-(difluoromethyl)-4,5-dihydro-5-oxo-1H-1,2,4-triazol-1-
ylphenylmethanesulfonamide), in or on crop group 10-10 citrus fruit at 0.15 ppm; crop group 13-07 berry and small fruit at 0.15 ppm; crop group 14 tree nut and pistachio at 0.15 ppm; and crop group 18 non-
grass animal feed (forage, fodder, straw, and hay): Alfalfa, forage at 5 ppm; alfalfa, hay at 20 ppm; alfalfa, seed at 3 ppm; clover, forage at 5 ppm; clover, hay at 20 ppm; and clover, seed at 3 ppm. That notice referenced a summary of the petition prepared by FMC, the registrant, which is available in the docket, http://www.regulations.gov. A comment was received on the notice of filing. EPA's response to this comment is discussed in Unit IV.C.
Based upon review of the data supporting the petition, EPA has modified the tolerance levels for some commodities and is not establishing tolerances on alfalfa forage, hay, and seed and clover forage, hay, and seed. The reasons for these changes are explained in Unit IV.D.
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Aggregate Risk Assessment and Determination of Safety
Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a tolerance (the legal limit for a pesticide chemical residue in or on a food) only if EPA determines that the tolerance is ``safe.'' Section 408(b)(2)(A)(ii) of FFDCA defines ``safe'' to mean that ``there is a reasonable certainty that no harm will result from aggregate exposure to the pesticide chemical residue, including all anticipated dietary exposures and all other exposures for which there is reliable information.'' This includes exposure through drinking water and in residential settings, but does not include occupational exposure. Section 408(b)(2)(C) of FFDCA requires EPA to give special consideration to exposure of infants and children to the pesticide chemical residue in establishing a tolerance and to ``ensure that there is a reasonable certainty that no harm will result to infants and children from aggregate exposure to the pesticide chemical residue. * * *''
Consistent with FFDCA section 408(b)(2)(D), and the factors specified in FFDCA section 408(b)(2)(D), EPA has reviewed the available scientific data and other relevant information in support of this action. EPA has sufficient data to assess the hazards of and to make a determination on aggregate exposure for sulfentrazone including exposure resulting from the tolerances established by this action. EPA's assessment of exposures and risks associated with sulfentrazone follows.
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Toxicological Profile
EPA has evaluated the available toxicity data and considered its validity, completeness, and reliability as well as the relationship of the results of the studies to human risk. EPA has also considered available information concerning the variability of the sensitivities of major identifiable subgroups of consumers, including infants and children.
Based on the results of acute toxicity studies in rats, sulfentrazone was classified as having low acute toxicity via the oral, dermal, and inhalation routes of exposure. It is a mild eye
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irritant, but not a dermal irritant or sensitizer. Subchronic and chronic toxicity studies in rats, mice and dogs identified the hematopoietic system as the target of sulfentrazone. Protoporphyrinogen oxidase inhibition in the mammalian species may result in disruption of heme synthesis. In these studies, disruption of heme synthesis was observed at about the same dose levels across species, except in the case of mice, where the effects were seen at a slightly higher dose. The hematotoxicity occurred around the same dose level for short- through long-term exposure without increasing in severity.
In the oral and dermal rat developmental toxicity studies, decreased fetal body weights and reduced/delayed skeletal ossifications were noted at doses that were not maternally toxic. In rabbits, developmental effects such as decreased pup viability were observed at a maternally toxic dose (clinical signs, abortions and decreased body weight gains). In the 2-generation reproduction study in rats, offspring effects such as decreased body weights and decreased litter survival were observed at a maternally toxic dose (slightly decreased body weight gain).
In the acute neurotoxicity study, an increased incidence of clinical signs (staggered gait, splayed hind limbs, and abdominal gripping), changes in functional observation battery (FOB) parameters, and decreased motor activity were observed; however, complete recovery was observed within 14 days and there was no evidence of neuropathology. In the subchronic neurotoxicity study, clinical signs of toxicity, increased motor activity, and/or decreased body weights, body-weight gain, and food consumption were observed. There was no evidence of neuropathology in either study. A published, non-guideline developmental toxicity study in the rat (de Castro, et al., 2007) failed to demonstrate conclusively developmental neurotoxicity and contains several shortcomings that limit its use for regulatory purposes. Further, the reported offspring effects involving measures of physical and reflex development are likely secondary effects reflective of the poor general state of the offspring, as reported in the rat 2-
generation reproductive toxicity study at similar dose levels.
No systemic toxicity was seen via the dermal route up to the limit dose in a 28-day dermal toxicity study in rabbits.
Preliminary review of a recently submitted 28-day rat immunotoxicity study suggests that sulfentrazone does not directly target the immune system; and, there is no evidence of immunotoxicity in the rest of the toxicity database for sulfentrazone.
Carcinogenicity studies in rats and mice showed no evidence of increased incidence of tumor formation due to treatment with sulfentrazone. Therefore, the EPA classified sulfentrazone as ``not likely to be carcinogenic to humans.'' The available mutagenicity studies indicate that sulfentrazone is weakly clastogenic in the in vitro mouse lymphoma assay in the absence of S9 activation; however, the response was not evident in the presence of S9 activation. Sulfentrazone is neither mutagenic in bacterial cells, nor clastogenic in male or female mice in vivo. Specific information on the studies received and the nature of the adverse effects caused by sulfentrazone as well as the no-observed-adverse-effect-level (NOAEL) and the lowest-
observed-adverse-effect-level (LOAEL) from the toxicity studies can be found at http://www.regulations.gov in the document titled ``Sulfentrazone: Human-Health Risk Assessment for the Establishment of Sulfentrazone Tolerances in/on: Rhubarb, Turnip Roots and Tops, Sunflower Subgroup 20B, Succulent Cowpea, Succulent Lima Bean, Succulent Vegetable Soybean, Wheat (Spring), Citrus Fruit Group 10-10, Low-Growing Berry Group 13-07, Tree Nut Group 14, Pistachios, and Crop Group 18 Nongrass Animal Feeds,'' pp. 45-49 in docket ID number EPA-HQ-
OPP-2011-0758.
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Toxicological Points of Departure/Levels of Concern
Once a pesticide's toxicological profile is determined, EPA identifies toxicological points of departure (POD) and levels of concern (LOC) to use in evaluating the risk posed by human exposure to the pesticide. For hazards that have a threshold below which there is no appreciable risk, the toxicological POD is used as the basis for derivation of reference values for risk assessment. PODs are developed based on a careful analysis of the doses in each toxicological study to determine the dose at which no adverse effects are observed (the NOAEL) and the lowest dose at which adverse effects of concern are identified (the LOAEL). Uncertainty/safety factors are used in conjunction with the POD to calculate a safe exposure level--generally referred to as a population-adjusted dose (PAD) or a reference dose (RfD)--and a safe margin of exposure (MOE). For non-threshold risks, the Agency assumes that any amount of exposure will lead to some degree of risk. Thus, the Agency estimates risk in terms of the probability of an occurrence of the adverse effect expected in a lifetime. For more information on the general principles EPA uses in risk characterization and a complete description of the risk assessment process, see http://www.epa.gov/pesticides/factsheets/riskassess.htm.
A summary of the toxicological endpoints for sulfentrazone used for human risk assessment is shown in the following table:
Table--Summary of Toxicological Doses and Endpoints for Sulfentrazone for Use in Human Health Risk Assessment
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Point of departure
Exposure/scenario and uncertainty/ RfD, PAD, LOC for Study and toxicological effects
safety factors risk assessment
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Acute dietary (Females 13-49 NOAEL = 14 mg/kg/day Acute RfD = 0.14 mg/ 2-Generation Reproductive Toxicity
years of age). UFA = 10X........... kg/day Study--Rat Offspring Toxicity
UFH = 10X........... aPAD = 0.14 mg/kg/ LOAEL = 33 (M) and 40 (F) mg/kg/
FQPA SF = 1X........ day. day based on reduced prenatal
viability (fetal & litter),
reduced litter size, increased
number of stillborn pups, reduced
pup and litter postnatal
survival, and decreased pup body
weights throughout lactation.
Acute dietary (General population NOAEL = 250 mg/kg/ Acute RfD = 2.5 mg/ Acute Neurotoxicity Study--Rat
including infants and children). day kg/day LOAEL = 750 mg/kg/day based on
UFA = 10X........... aPAD = 2.5 mg/kg/ increased incidence of clinical
UFH = 10X........... day. signs and FOB parameters and
FQPA SF = 1X........ decreased motor activity.
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Chronic dietary (All populations) NOAEL = 14 mg/kg/day Chronic RfD = 0.14 2-Generation Reproductive Toxicity
UFA = 10X........... mg/kg/day Study--Rat Offspring Toxicity
UFH = 10X........... cPAD = 0.14 mg/kg/ LOAEL = 33 (M) and 40 (F) mg/kg/
FQPA SF = 1X........ day. day based on reduced prenatal
viability (fetal & litter),
reduced litter size, increased
number of stillborn pups, reduced
pup and litter postnatal
survival, and decreased pup body
weights throughout lactation.
Short- (1-30 days) and NOAEL = 14 mg/kg/day LOC for MOE = 100 2-Generation Reproduction Study--
Intermediate-Term (1-6 months) UFA = 10X........... Rat Offspring LOAEL = 33 mg/kg/
Incidental Oral. UFH = 10X........... day based on decreased pup body
FQPA SF = 1X........ weights and reduced postnatal
survival in both generations.
Short-Term Dermal (1-30 days).... Dermal study LOC for MOE = 100 Dermal Developmental Study--Rat
NOAEL = 100 mg/kg/ LOAEL = 250 mg/kg/day based on
day (dermal decreased fetal body weight;
absorption rate = increased incidences of fetal
100%). skeletal variations: Hypoplastic
UFA = 10X........... or wavy ribs, incompletely
UFH = 10X........... ossified lumbar vertebral arches,
FQPA SF = 1X........ and incompletely ossified ischia
or pubes; and reduced number of
thoracic vertebral and rib
ossification sites.
Short-Term Inhalation (1-30 days) Inhalation (or oral) LOC for MOE = 1000 Prenatal Developmental Toxicity--
study Rat Developmental LOAEL = 25 mg/
NOAEL = 10 mg/kg/day kg/day, based upon decreased mean
(inhalation fetal weights, and retardation in
absorption rate = skeletal development evidenced by
100%). an increased number of litters
UFA = 10X........... with any variation and by
UFH = 10X........... decreased number of caudal
FQPA SF = 10X....... vertebral and metacarpal
ossification sites.
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FQPA SF = Food Quality Protection Act Safety Factor. LOAEL = lowest-observed-adverse-effect-level. LOC = level
of concern. mg/kg/day = milligram/kilogram/day. MOE = margin of exposure. NOAEL = no-observed-adverse-effect-
level. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. UF = uncertainty factor.
UFA = extrapolation from animal to human (interspecies). UFDB = to account for the absence of data or other
data deficiency. UFH = potential variation in sensitivity among members of the human population
(intraspecies). M = male. F = female. FOB = functional observation battery.
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Exposure Assessment
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Dietary exposure from food and feed uses. In evaluating dietary exposure to sulfentrazone, EPA considered exposure under the petitioned-for tolerances as well as all existing sulfentrazone tolerances in 40 CFR 180.498. EPA assessed dietary exposures from sulfentrazone in food as follows:
i. Acute exposure. Quantitative acute dietary exposure and risk assessments are performed for a food-use pesticide, if a toxicological study has indicated the possibility of an effect of concern occurring as a result of a 1-day or single exposure. Such effects were identified for sulfentrazone. EPA performed separate acute risk assessments for females 13 to 49 years old and for the general population, including infants and children, based on different endpoints and aPADs. In estimating acute dietary exposure, EPA used food consumption information from the United States Department of Agriculture (USDA) 1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by Individuals (CSFII). As to residue levels in food, EPA used tolerance-
level residues, dietary exposure evaluation model DEEMTM (ver. 7.81) default processing factors, and assumed 100 percent crop treated (PCT) for all commodities.
ii. Chronic exposure. In conducting the chronic dietary exposure assessment EPA used the food consumption data from the USDA 1994-1996 and 1998 CSFII. As to residue levels in food, EPA used tolerance-level residues, DEEMTM (ver. 7.81) default processing factors, and assumed 100 PCT for all commodities.
iii. Cancer. Based on the data summarized in Unit III.A., EPA has concluded that sulfentrazone does not pose a cancer risk to humans. Therefore, a dietary exposure assessment for the purpose of assessing cancer risk is unnecessary.
iv. Anticipated residue and PCT information. EPA did not use anticipated residue or PCT information in the dietary assessment for sulfentrazone. Tolerance level residues and 100 PCT were assumed for all food commodities.
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Dietary exposure from drinking water. The Agency used screening level water exposure models in the dietary exposure analysis and risk assessment for sulfentrazone in drinking water. These simulation models take into account data on the physical, chemical, and fate/transport characteristics of sulfentrazone. Further information regarding EPA drinking water models used in pesticide exposure assessment can be found at http://www.epa.gov/oppefed1/models/water/index.htm.
Sulfentrazone and 3-carboxylic acid sulfentrazone are the residues of concern in drinking water. Therefore, the First Index Reservoir Screening Tool (FIRST) model was used to estimate concentrations of sulfentrazone and 3-carboxylic acid sulfentrazone in surface water, and the Screening Concentration in Ground Water (SCI-GROW) model was utilized to estimate concentrations in ground water. The estimated drinking water concentrations (EDWCs) of sulfentrazone and 3-
carbyoxylic acid sulfentrazone for acute exposures are estimated to be 35.8 parts per billion (ppb) for surface water and 26.0 ppb for ground water. For chronic exposures for non-cancer assessments, EDWCs are
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estimated to be 7.8 ppb for surface water and 26.0 ppb for ground water.
Modeled estimates of drinking water concentrations were directly entered into the dietary exposure model. For acute dietary risk assessment, the water concentration value of 35.8 ppb was used to assess the contribution to drinking water. For chronic dietary risk assessment, the water concentration of value 26.0 ppb was used to assess the contribution to drinking water.
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From non-dietary exposure. The term ``residential exposure'' is used in this document to refer to non-occupational, non-dietary exposure (e.g., for lawn and garden pest control, indoor pest control, termiticides, and flea and tick control on pets).
Sulfentrazone is currently registered for the following use that could result in residential exposures: Residential home lawns/turf and recreational turf, such as golf courses. EPA assessed residential exposure using the following assumptions: Adults were assessed for potential short-term dermal and inhalation handler exposure from applying sulfentrazone to residential turf/home lawns and for short-
term post-application dermal exposure from contact with treated residential and recreational turf home lawns and golf courses. For adult handlers, dermal and inhalation exposures were aggregated for the short-term assessment. Because the level of concern for dermal exposures (MOEs less than 100) and inhalation exposure (MOEs less than 1,000) are different, a total aggregate risk index (ARI) approach was used for adult handlers instead of the MOE approach. ARIs of less than 1 indicate risks are not of concern. Children, ages 11
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