Source: https://www.federalregister.gov/documents/2012/12/03/2012-29105/halosulfuron-methyl-pesticide-tolerances
Timestamp: 2017-08-16 19:43:58
Document Index: 10817127

Matched Legal Cases: ['art 178', 'art 180', 'art 178', 'art 178', 'art 2', 'art 158', '§\u2009180']

A Rule by the Environmental Protection Agency on 12/03/2012
This regulation is effective December 3, 2012. Objections and requests for hearings must be received on or before February 1, 2013, and must be filed in accordance with the instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).
77 FR 71555
71555-71561 (7 pages)
EPA-HQ-OPP-2011-0781
FRL-9370-6
2012-29105
Dietary Risk Assessment for Halosulfuron-methyl Applications...
Residue Chemistry Memo for applications of Halosulfuron-methyl...
Human Health Risk Assessment for Halosulfuron-methyl...
EPA Registration Division Company Notice of Filing For...
https://www.federalregister.gov/d/2012-29105 https://www.federalregister.gov/d/2012-29105
This regulation establishes tolerances for residues of halosulfuron-methyl in or on multiple commodities which are identified and discussed later in this document. Canyon Group L.L.C., c/o Gowan Company requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA).
The docket for this action, identified by docket identification (ID) number EPA-HQ-OPP-2011-0781, is available at http://www.regulations.gov or at the Office of Pesticide Programs Regulatory Public Docket (OPP Docket) in the Environmental Protection Agency Docket Center (EPA/DC), EPA West Bldg., 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.
Maggie Rudick, Registration Division (7505P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460-0001; telephone number: (703) 347-0257; email address: rudick.maggie@epa.gov.
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?&amp;c=ecfr&amp;tpl=/ecfrbrowse/Title40/40tab_02.tpl. To access the OCSPP test guidelines referenced in this document electronically, please go to http://www.epa.gov/ocspp and select “Test Methods and Guidelines.”
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-2011-0781 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 February 1, 2013. Addresses for mail and hand delivery of objections 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 (excluding any Confidential Business Information (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 the non-CBI copy of your objection or hearing request, identified by docket ID number EPA-HQ-OPP-2011-0781, by one of the following methods:
In the Federal Register of December 8, 2011 (75 FR 76676) (FRL-9328-8), EPA issued a document pursuant to FFDCA section 408(d)(3), 21 U.S.C. 346a(d)(3), announcing the filing of a pesticide petition (PP 1F7916) by Canyon Group L.L.C., c/o Gowan Company, 370 South Main St., Yuma, AZ 85364. The petition requested that 40 CFR 180.479 be amended by establishing tolerances for residues of the herbicide halosulfuron-methyl, methyl 5-[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonylaminosulfonyl]-3-chloro-1-methyl-1H-pyrazole-4-carboxylate, in or on millet, proso, forage at 7.0 parts per million (ppm); millet, proso, hay at 0.02 ppm; millet, proso, grain at 0.01 ppm; millet, proso, straw at 0.01 ppm; grass, forage, fodder, and hay, group 17, forage at 17 ppm; and grass, forage, fodder, and hay, group 17, hay at 0.90 ppm. That document referenced a summary of the petition prepared by Canyon Group, L.L.C., the registrant, which is available in the docket, http://www.regulations.gov. Comments were received on the notice of filing. EPA's response to these comments is discussed in Unit IV.C.
Based upon review of the data supporting the petition, EPA has revised the proposed tolerance levels, determined that established tolerances for certain livestock commodities should be increased and multiple new livestock commodity tolerances should be established. The reasons for these changes are explained in Unit IV.D.
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 halosulfuron-methyl including exposure resulting from the tolerances established by this action. EPA's assessment of exposures and risks associated with halosulfuron-methyl follows.
Halosulfuron-methyl has a low acute toxicity via the oral, dermal, and inhalation routes of exposure. Halosulfuron-methyl is a non-irritant for skin and eyes and is not a dermal sensitizer.
With repeated dosing, halosulfuron-methyl produces non-specific effects, which are frequently characterized by reduced body weight/body weight gain in the test animals. The available data show that the dog is the most sensitive mammalian species. In the dog, decreased body weight was seen in the chronic oral toxicity study and decreased body weight gain was observed in females in the subchronic oral toxicity study. In the rat and mouse, there was a decrease in body weight gains at high dose levels in short- and long-term oral and dermal studies.
In the prenatal developmental toxicity study in rats, increases in resorptions, soft tissue (dilation of the lateral ventricles) and skeletal variations, and decreases in body weights were seen in the fetuses compared to clinical signs and decreases in body weights and food consumption in the maternal animals at similar dose level.
In the rabbit developmental toxicity study, increases in resorptions and post-implantation losses and decrease in mean litter size was seen in the presence of decreases in body weight and food consumption in maternal animals were observed. However, a clear no-observed-adverse-effect-level (NOAEL) for these effects was established in both rat and rabbit developmental toxicity studies.
Halosulfuron-methyl did not produce reproductive effects. No neurotoxic effects were observed in the acute or subchronic neurotoxicity studies. Halosulfuron-methyl is classified as “not likely to be carcinogenic to humans” because in both rat and mouse carcinogenicity studies halosulfuron-methyl does not cause; compound-related increases in tumor incidence. It is negative for mutagenicity in a battery of genotoxicity studies. Specific information on the studies received and the nature of the adverse effects caused by halosulfuron-methyl as well as the NOAEL and the lowest-observed-adverse-effect-level (LOAEL) from the toxicity studies can be found at http://www.regulations.gov in the document Halosulfuron-methyl: “Human Health Risk Assessment for Proposed New Uses on Proso Millet and Crop Group 17 (Grass, Forage, Fodder, and Hay)” at p. 19 in docket ID number EPA-HQ-OPP-2011-0781.
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 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 halosulfuron-methyl used for human risk assessment is shown in the following Table.
Table—Summary of Toxicological Doses and Endpoints for Halosulfuron-Methyl for Use in Human Health Risk Assessment
Acute dietary (Females 13-50 years of age) NOAEL = 50 mg/kg/day UFA = 10X UFH = 10X FQPA SF = 1X Acute RfD = 0.5 mg/kg/day aPAD = 0.5 mg/kg/day Developmental Toxicity—Rabbit. LOAEL = 150 mg/kg/day based on decreased mean litter size, increased number of resorptions (total and per dam) and increased post-implantation loss (developmental toxicity).
Acute dietary (General population including infants and children) N/A N/A No adverse effect attributable to a single dose was identified; therefore, no dose/endpoint was selected for this exposure scenario.
Chronic dietary (All populations) NOAEL = 10 mg/kg/day UFA = 10X UFH = 10X FQPA SF = 1X Chronic RfD = 0.1 mg/kg/day cPAD = 0.1 mg/kg/day Chronic Toxicity—Dog. LOAEL = 40 mg/kg/day based on decreased body weight gains in females.
Incidental oral short-term (1 to 30 days) NOAEL = 50 mg/kg/day UFA = 10X UFH = 10X FQPA SF = 1X LOC for MOE = 100 Developmental Toxicity—Rabbit. LOAEL = 150 mg/kg/day based on decreased body weight gain, food consumption, and food efficiency (maternal toxicity).
Incidental oral intermediate-term (1 to 6 months) NOAEL = 10 mg/kg/day UFA= 10X UFH= 10X FQPA SF = 1X LOC for MOE = 100 13 Week Subchronic Toxicity—Dog. LOAEL = 40 mg/kg/day based on decreased body weight gains and food efficiency along with hematological and clinical chemistry changes.
Dermal short-term (1 to 30 days) NOAEL = 100 mg/kg/day UFA = 10X UFH = 10X FQPA SF = 1X LOC for MOE = 100 21 Day Dermal Toxicity Study—Rats. LOAEL = 1,000 mg/kg/day based on decreased body weight gains in males.
Dermal intermediate-term (1 to 6 months) NOAEL = 10 mg/kg/day UFA = 10X UFH = 10X FQPA SF = 1X LOC for MOE = 100 13 Week Subchronic Toxicity—Dog. LOAEL = 40 mg/kg/day based on decreased body weight gains and food efficiency along with hematological and clinical chemistry changes.
Inhalation short-term (1 to 30 days) NOAEL = 50 mg/kg/day UFA = 10X UFH = 10X FQPA SF = 1X LOC for MOE = 100 Developmental Toxicity—Rabbit. LOAEL = 150 mg/kg/day based on decreased body weight gain, food consumption, and food efficiency (maternal toxicity).
Inhalation (1 to 6 months) NOAEL = 10 mg/kg/day UFA = 10X UFH = 10X FQPA SF = 1X LOC for MOE = 100 13 Week Subchronic Toxicity—Dog. LOAEL = 40 mg/kg/day based on decreased body weight gains and food efficiency along with hematological and clinical chemistry changes.
Cancer (Oral, dermal, inhalation) Based on the results of carcinogenicity studies in rats and mice, EPA classified halosulfuron-methyl as “not likely to be carcinogenic to humans.” Therefore, an exposure assessment to evaluate cancer risk is unnecessary for this chemical.
1. Dietary exposure from food and feed uses. In evaluating dietary exposure to halosulfuron-methyl, EPA considered exposure under the petitioned-for tolerances as well as all existing halosulfuron-methyl tolerances in 40 CFR 180.479. EPA assessed dietary exposures from halosulfuron-methyl 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 halosulfuron-methyl. In estimating acute dietary exposure, EPA used food consumption information from the U.S. Department of Agriculture (USDA) 1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by Individuals (CSFII). As to residue levels in food, EPA conducted an unrefined assessment that assumed 100 percent crop treated (PCT), dietary exposure evaluation model (DEEMTM) 7.81 default concentration factors, and tolerance-level residues for all existing and proposed uses. There was no indication of an adverse effect attributable to a single dose for the general U.S. population. Therefore, an acute dietary assessment was not conducted for the general U.S. population.
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 conducted a chronic dietary assessment that utilized the same food residue assumptions as in the acute dietary exposure assessment discussed in Unit III.C.1.i.
iii. Cancer. In both rat and mouse carcinogenicity studies, halosulfuron-methyl does not produce compound related increases in tumor incidence; EPA has concluded that halosulfuron-methyl 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 and/or PCT information in the dietary assessment for halosulfuron-methyl. Tolerance level residues and/or 100 PCT were assumed for all food commodities.
2. Dietary exposure from drinking water. The Agency used screening level water exposure models in the dietary exposure analysis and risk assessment for halosulfuron-methyl in drinking water. These simulation models take into account data on the physical, chemical, and fate/transport characteristics of halosulfuron-methyl. 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.
Based on the Tier 1 Rice Model and Screening Concentration in Ground Water (SCI-GROW) models, the estimated drinking water concentrations (EDWCs) of halosulfuron-methyl for acute and chronic exposures are estimated to be 59.2 parts per billion (ppb) for surface water and 0.065 ppb for ground water.
Modeled estimates of drinking water concentrations were directly entered into the dietary exposure model. For both acute and chronic dietary risk assessments, the water concentration value of 59.2 ppb was used to assess the contribution to drinking water.
3. 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). Halosulfuron-methyl is currently registered for the following uses that could result in residential exposures: Residential turf. EPA assessed residential exposure using the default assumptions of the 2012 Residential Standard Operating Procedures (SOPs). Residential handler short-term (1-30 days) dermal and inhalation exposures, and residential post-application short-term dermal and incidental oral (hand-to-mouth, object-to-mouth, and soil ingestion) exposures are expected from activities associated with the existing uses. Intermediate-term exposures are not likely because of the intermittent nature of applications by homeowners. Further information regarding EPA standard assumptions and generic inputs for residential exposures may be found at http://www.epa.gov/pesticides/trac/science/trac6a05.pdf.
4. Cumulative effects from substances with a common mechanism of toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when considering whether to establish, modify, or revoke a tolerance, the Agency consider “available information” concerning the cumulative effects of a particular pesticide's residues and “other substances that have a common mechanism of toxicity.” EPA has not found halosulfuron-methyl to share a common mechanism of toxicity with any other substances, and halosulfuron-methyl does not appear to produce a toxic metabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has assumed that halosulfuron-methyl does not have a common mechanism of toxicity with other substances. For information regarding EPA's efforts to determine which chemicals have a common mechanism of toxicity and to evaluate the cumulative effects of such chemicals, see EPA's Web site at http://www.epa.gov/pesticides/cumulative.
2. Prenatal and postnatal sensitivity. The pre-natal and postnatal toxicity database for halosulfuron-methyl includes rat and rabbit developmental toxicity studies and a 2-generation reproduction toxicity study in rats. As discussed in Unit III.A, there was qualitative evidence of increased susceptibility of fetuses in the rat and rabbit developmental studies. Fetal effects e.g., increased incidences of soft tissue and skeletal variations, decreased mean fetal body weight and mean litter size in the rat study; increases in resorptions and post-implantation losses and a decrease in mean litter size in the rabbit study, occurred at doses resulting in less severe maternal toxicity e.g., increased incidence of clinical observations, reduced body weight gains, reduced food consumption and food efficiency in the rat study; decreases in body weight and food consumption in the rabbit study. The degree of concern for these effects is low, and there are no residual uncertainties for prenatal toxicity in rats and rabbits for the following reasons: In both studies, there are clear NOAELs/LOAELs for developmental and maternal toxicities; developmental effects were seen in the presence of maternal toxicity; and effects were seen only at the high dose. Additionally, in rats, developmental effects were seen at a dose which is approaching the limit-dose.
i. The toxicity database for halosulfuron-methyl is complete except for an immunotoxicity study. In accordance with 40 CFR part 158, Toxicology Data Requirements, an immunotoxicity study is required for halosulfuron-methyl. In the absence of specific immunotoxicity studies, EPA has evaluated the available halosulfuron-methyl toxicity data to determine whether an additional uncertainty factor is needed to account for potential immunotoxicity. The toxicology database for halosulfuron-methyl does not show any evidence of biologically relevant effects on the immune system following exposure to this chemical. The overall weight of evidence suggests that this chemical does not directly target the immune system. Based on these considerations, EPA does not believe that conducting immunotoxicity testing will result in a POD lower than those already selected for halosulfuron-methyl risk assessment, and an additional database uncertainty factor is not needed to account for the lack of this study.
iv. There are no residual uncertainties identified in the exposure databases. The dietary food exposure assessments were performed based on 100 PCT and tolerance-level residues. EPA made conservative (protective) assumptions in the ground and surface water modeling used to assess exposure to halosulfuron-methyl in drinking water. EPA used similarly conservative assumptions to assess post application exposure of children as well as incidental oral exposure of toddlers. These assessments will not underestimate the exposure and risks posed by halosulfuron-methyl.
1. Acute risk. Using the exposure assumptions discussed in this unit for acute exposure, the acute dietary exposure from food and water to halosulfuron-methyl will occupy <1% of the aPAD for females 13-49 years old, the population group receiving the greatest exposure.
2. Chronic risk. Using the exposure assumptions described in this unit for chronic exposure, EPA has concluded that chronic exposure to halosulfuron-methyl from food and water will utilize 6% of the cPAD for all infants, the population group receiving the greatest exposure. Based on the explanation in Unit III.C.3., regarding residential use patterns, chronic residential exposure to residues of halosulfuron-methyl is not expected.
3. Short-term risk. Short-term aggregate exposure takes into account short-term residential exposure plus chronic exposure to food and water (considered to be a background exposure level). Halosulfuron-methyl is currently registered for uses that could result in short-term residential exposure, and the Agency has determined that it is appropriate to aggregate chronic exposure through food and water with short-term residential exposures to halosulfuron-methyl.
Using the exposure assumptions described in this unit for short-term exposures, EPA has concluded the combined short-term food, water, and residential exposures result in aggregate MOEs of 1,800 for adults and 840 for children. For adults, potential pathways of exposure include oral (background) and dermal (post-application primary) routes, while for children, potential pathways of exposure include oral (background) and incidental oral and dermal (primary) routes. Because EPA's level of concern for halosulfuron-methyl is a MOE of 100 or below, these MOEs are not of concern.
4. Intermediate-term risk. Intermediate-term aggregate exposure takes into account intermediate-term residential exposure plus chronic exposure to food and water (considered to be a background exposure level). An intermediate-term adverse effect was identified; however, halosulfuron-methyl is not registered for any use patterns that would result in intermediate-term residential exposure. Intermediate-term risk is assessed based on intermediate-term residential exposure plus chronic dietary exposure. Because there is no intermediate-term residential exposure and chronic dietary exposure has already been assessed under the appropriately protective cPAD (which is at least as protective as the POD used to assess intermediate-term risk), no further assessment of intermediate-term risk is necessary, and EPA relies on the chronic dietary risk assessment for evaluating intermediate-term risk for halosulfuron-methyl.
5. Aggregate cancer risk for U.S. population. Based on the lack of evidence of carcinogenicity in two adequate rodent carcinogenicity studies, halosulfuron-methyl is not expected to pose a cancer risk to humans.
Adequate enforcement methodologies are available to enforce the tolerance expression: A gas chromatography with nitrogen phosphorus detection; GC/NPD method for crop commodities and a gas chromotagraphy with electron capture detection (GC/ECD) method for livestock commodities. The methods may be requested from: Chief, Analytical Chemistry Branch, Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD 20755-5350; telephone number: (410) 305-2905; email address: residuemethods@epa.gov.
In making its tolerance decisions, EPA seeks to harmonize U.S. tolerances with international standards whenever possible, consistent with U.S. food safety standards and agricultural practices. EPA considers the international maximum residue limits (MRLs) established by the Codex Alimentarius Commission (Codex), as required by FFDCA section 408(b)(4). The Codex Alimentarius is a joint United Nations Food and Agriculture Organization/World Health Organization food standards program, and it is recognized as an international food safety standards-setting organization in trade agreements to which the United States is a party. EPA may establish a tolerance that is different from a Codex MRL; however, FFDCA section 408(b)(4) requires that EPA explain the reasons for departing from the Codex level. There are no Maximum Residue Limits (MRLs) established by Codex, Canada, or Mexico for any crop or livestock commodities for halosulfuron-methyl.
An anonymous citizen objected to the presence of any pesticide residues on food. The Agency understands the commenter's concerns and recognizes that some individuals believe that pesticides should be banned completely. However, the existing legal framework provided by section 408 of the FFDCA contemplates that tolerances greater than zero may be set when persons seeking such tolerances or exemptions have demonstrated that the pesticide meets the safety standard imposed by that statute. This citizen's comment appears to be directed at the underlying statute and not EPA's implementation of it; the citizen has made no contention that EPA has acted in violation of the statutory framework.
EPA has revised the requested tolerances by increasing the tolerance values for millet, proso, forage and grass, forage, fodder, and hay, group 17, forage and reducing the tolerance values for millet, proso, hay and grass, forage, fodder, and hay, group 17, hay. Differences in proposed and recommended tolerances may be attributed to the petitioner having used the North American Free Trade Agreement (NAFTA) tolerance calculation procedures for determining the tolerance and EPA's use of the Organization for Economic Cooperation and Development (OECD) tolerance calculation procedures. Recently, EPA has adopted use of the OECD tolerance calculation procedures to increase international harmonization of tolerance levels. For grass hay, the petitioner used values below the level of quantitation (LOQ) in the tolerance calculation whereas EPA used LOQ values. In addition, already established tolerances for cattle, goat, horse, and sheep meat byproducts are being increased and multiple new livestock commodity tolerances are being established. Livestock tolerances are derived from reevaluation of the dairy/beef cattle diet with new feed items (millet and grass).
Therefore, tolerances are established for residues of halosulfuron-methyl, including its metabolites and degradates, as set forth in the regulatory text.
2. In § 180.479 revise the table in paragraph (a)(1) and add alphabetically the following new entries to the table in paragraph (a)(2).
Grass, forage, fodder, and hay, group 17, forage 20
Grass, forage, fodder, and hay, group 17, hay 0.5
Millet, proso, forage 10
Millet, proso, grain 0.01
Millet, proso, hay 0.01
Millet, proso, straw 0.01
[FR Doc. 2012-29105 Filed 11-30-12; 8:45 am]