ACTION
Final Rule.
SUMMARY
This regulation establishes tolerances for residues of S-metolachlor in or on multiple commodities which are identified and discussed later in this docu
ment. Interregio
nal Research Project Number 4 (IR-4) requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA).
TABLE OF CONTENTS
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DATES:
ADDRESSES:
FOR FURTHER INFORMATION CONTACT:
SUPPLEMENTARY INFORMATION:
I. General Information
A. Does this action apply to me?
B. How can I get electro
nic access to other related information?
C. How can I file an objection or hearing request?
II. Summary of Petitioned-For Tolerance
III. Aggregate Risk Assessment and Determination of Safety
A. Toxicological Profile
B. Toxicological Points of Departure/Levels of Concern
C. Exposure Assessment
D. Safety Factor for Infants and Children
E. Aggregate Risks and Determination of Safety
IV. Other Considerations
A. Analytical Enforcement Methodology
B. Internatio
nal Residue Limits
C. Revisions to Petitioned-For Tolerances
V. Conclusion
VI. Statutory and Executive Order Reviews
VII. Co
ngressional Review Act
List of Subjects in 40 CFR Part 180
PART 180—[AMENDED]
TABLES
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Table 1—Summary of Toxicological Doses and Endpoints for S-metolachlor for Use in Human Health Risk Assessment
DATES:
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This regulation is effective July 8, 2015. Objections and requests for hearings must be received on or before September 8, 2015, 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:
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The docket for this action, identified by docket identification (ID) number EPA-HQ-OPP-2014-0284, is available at http://www.regulations.gov or at the Office of Pesticide Programs Regulatory Public Docket (OPP Docket) in the Enviro
nmental Protection Agency Docket Center (EPA/DC), West William Jefferson Clinton Bldg., Rm. 3334, 1301 Co
nstitution Ave. NW., Washington, DC 20460-0001. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Mo
nday 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 additio
nal information a
bout the docket available at http://www.epa.gov/dockets.
FOR FURTHER INFORMATION CONTACT:
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Susan Lewis, Registration Division (7505P), Office of Pesticide Programs, Enviro
nmental Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460-0001; main telephone number: (703) 305-7090; email address: RDFRNotices@epa.gov.
SUPPLEMENTARY INFORMATION:
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I. General Information
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A. 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. The following list of North American Industrial Classification System (NAICS) codes is not intended to be exhaustive, but rather provides a guide to help readers determine whether this docu
ment applies to them. Potentially affected entities may include:
Crop production (NAICS code 111).
Animal production (NAICS code 112).
Food manufacturing (NAICS code 311).
Pesticide manufacturing (NAICS code 32532).
B. How can I get electro
nic access to other related information?
You may access a frequently updated electro
nic version of EPA's tolerance regulations at 40 CFR part 180 through the Government Printing Office's e-CFR site at http://www.ecfr.gov/cgi-bin/text-idx?&c=ecfr&tpl=/ecfrbrowse/Title40/40tab_02.tpl.
C. 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-2014-0284 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 8, 2015. 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 Co
nfidential Business Information (CBI)) for inclusion in the public docket. Information not marked co
nfidential 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-2014-0284, by one of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov. Follow the o
nline instructions for submitting comments. Do not submit electro
nically any information you co
nsider to be CBI or other information whose disclosure is restricted by statute.
Mail: OPP Docket, Enviro
nmental Protection Agency Docket Center (EPA/DC), (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.html.
Additio
nal instructions on commenting or visiting the docket, along with more information a
bout dockets generally, is available at http://www.epa.gov/dockets.
II. Summary of Petitioned-For Tolerance
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In the Federal Register of December 17, 2014 (79 FR 75107) (FRL-9918-90), EPA issued a docu
ment pursuant to FFDCA section 408(d)(3), 21 U.S.C. 346a(d)(3), announcing the filing of a pesticide petition (PP 4E8248) by IR-4 500 College Road East, Suite 201 W, Princeton, NJ 08540, requests to establish a tolerance in 40 CFR part 180 for residues of S-metolachlor in or on the raw agricultural commodity lettuce at 1.5 parts per million (ppm); vegetable, cucurbit group 9 at 0.50 ppm; vegetable, fruiting, group 8-10, except tabasco pepper at 0.10 ppm; low growing berry subgroup 13-07G except cranberry at 0.40 ppm; and sunflower subgroup 20B at 0.50 ppm and the co
ncurrent deletion of the existing tolerances for okra; vegetable, fruiting, group 8 except tabasco pepper; cucumber; melon subgroup 9A; pumpkin; squash, winter; and sunflower, seed. That docu
ment referenced a summary of the petition prepared by Syngenta Crop Protection, the registrant, which is available in the docket, http://www.regulations.gov. There were no comments received in respo
nse to the notice of filing.
ba
sed upon review of the data supporting the petition, EPA has modified the levels at which some of the tolerances are being established. The reason for these changes are explained in Unit IV.C.
III. Aggregate Risk Assessment and Determination of Safety
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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) o
nly if EPA determines that the tolerance is “safe.” Section 408(b)(2)(A)(ii) of FFDCA defines “safe” to mean that “there is a reaso
nable 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 occupatio
nal exposure. Section 408(b)(2)(C) of FFDCA requires EPA to give special co
nsideration to exposureof infants and children to the pesticide chemical residue in establishing a tolerance and to “ensure that there is a reaso
nable certainty that no harm will result to infants and children from aggregate exposure to the pesticide chemical residue. . . .”
Co
nsistent 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 S-metolachlor including exposure resulting from the tolerances established by this action. EPA's assessment of exposures and risks associated with S-metolachlor follows.
A. Toxicological Profile
EPA has e
valuated the available toxicity data and co
nsidered its validity, completeness, and reliability as well as the relatio
nship of the results of the studies to human risk. EPA has also co
nsidered available information co
ncerning the variability of the sensitivities of major identifiable subgroups of consumers, including infants and children.
The existing toxicological databa
se is primarily comprised of studies co
nducted with metolachlor. However, bridging studies indicate that the metolachlor toxicology databa
se can be used to assess toxicity for S-metolachlor. In subchro
nic (metolachlor and S-metolachlor) and chro
nic (metolachlor) toxicity studies in dogs and rats decreased body weight and body weight (bw) gain were the most commo
nly observed effects. No systemic toxicity was observed in rabbits when metolachlor was administered dermally. There was no evidence of neurotoxic effects in the available toxicity studies, and there is no evidence of Immunotoxicity in the submitted mouse Immunotoxicity study.
Prenatal developmental studies in the rat and rabbit with both metolachlor and S-metolachlor revealed no evidence of a qualitative or quantitative susceptibility in fetal animals. A 2-generation reproduction study with metolachlor in rats showed no evidence of parental or reproductive toxicity. There are no residual uncertainties with regard to pre- and/or postnatal toxicity.
Metolachlor has been e
valuated for carcinogenic effects in the mouse and the rat. Metolachlor did not cause an increase in tumors of any kind in mice. In rats, metolachlor caused an increase in benign liver tumors in rats, but this increase was seen o
nly at the highest dose tested and was statistically significant compared to co
ntrols o
nly in females. There was no evidence of mutagenic or cytogenetic effects in vivo or in vitro. ba
sed on this evidence, EPA has co
ncluded that metolachlor does not have a common mechanism of carcinogenicity with acetochlor and alachlor, compounds that are structurally similar to metolachlor. Metolachlor has been classified as a Group C, possible human carcinogen, ba
sed on liver tumors in rats at the highest dose tested (HDT).
Taking into account the qualitatively weak evidence on carcinogenic effects and the fact that the increase in benign tumors in female rats occurs at a dose 1,500 times the chro
nic reference dose (cRfD), EPA has co
ncluded that the cRfD is protective of any potential cancer effect.
Specific information on the studies received and the nature of the adverse effects caused by S-metolachlor 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 docu
ment “S-metolachlor—Risk Assessment for Establishment of Tolerances for New Uses on Lettuce, Low Growing Berry Subgroup 13-07G, except Cranberry; Vegetable, Cucurbit, Group 9; Sunflower subgroup 20B; Vegetable, Fruiting, Group 8-10; except Tabasco Pepper and Okra” on pp. 40 in docket ID number EPA-HQ-OPP-2014-0284.
B. Toxicological Points of Departure/Levels of Concern
o
nce a pesticide's toxicological profile is determined, EPA identifies toxicological points of departure (POD) and levels of co
ncern to use in e
valuating 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 ba
sed on a careful analysis of the doses in each toxicological study to determine the dose at which the NOAEL and the LOAEL are identified. Uncertainty/safety factors are used in co
njunction 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 des
cription of the risk assessment process, see http://www.epa.gov/pesticides/factsheets/riskassess.htm.
A summary of the toxicological endpoints for S-metolachlor used for human risk assessment is shown in Table 1 of this unit.
Table 1—Summary of Toxicological Doses and Endpoints for S-metolachlor for Use in Human Health Risk Assessment Back to Top
Exposure/scenarioPoint of departure and uncertainty/safety factorsRfD, PAD, LOC for risk assessmentStudy and toxicological effects
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. UF A= extrapolation from animal to human (interspecies). UF DB= to account for the absence of data or other data deficiency. UF H= potential variation in sensitivity among members of the human population (intraspecies).
Acute dietary (General population including infants and children)NOAEL = 300 mg/kg/dayAcute RfD = 3.0 mg/kg/dayDevelopmental Toxicity Study—Rat (metolachlor).
UF A= 10x UF H= 10x FQPA SF = 1x.aPAD = 3.0 mg/kg/dayLOAEL = 1,000 mg/kg/day ba
sed increased incidence of death, clinical signs (clo
nic and/or to
nic convulsions, excessive salivation, urine-stained abdominal fur and/or excessive lacrimation), and decreased body weight gain.
Chro
nic dietary (All populations)NOAEL= 9.7 mg/kg/dayChro
nic RfD = 0.097 mg/kg/dayOne Year Chro
nic Toxicity—Dog (metolachlor).
UF A= 10x UF H= 10x FQPA SF = 1x.cPAD = 0.097 mg/kg/dayLOAEL = 33 mg/kg/day ba
sed decreased body weight gain in females.
Incidental oral short-term (1 to 30 days)NOAEL= 50 mg/kg/dayLOC for MOE = 100Developmental Toxicity Study—Rat (S-metolachlor).
UF A= 10x UF H= 10x FQPA SF = 1x.LOAEL = 500 mg/kg/day ba
sed on increased incidence of clinical signs, decreased body weight/body weight gain, food co
nsumption and food efficiency seen in maternal animals.
Inhalation short-term (1 to 30 days)Inhalation (or oral) study NOAEL= 50 mg/kg/day (inhalation absorption rate = 100%)LOC for MOE = 1,000Developmental Toxicity Study—Rat (S-metolachlor).
UF A= 10x UF H= 10x FQPA SF = 10x UF DB.LOAEL = 500 mg/kg/day ba
sed on increased incidence of clinical signs, decreased body weight/body weight gain, food co
nsumption and food efficiency seen at the LOAEL in maternal animals.
Cancer (all routes)Metolachlor has been classified as a Group C carcinogen with risk quantitated using a non-linear RfD approach.
C. Exposure Assessment
1. Dietary exposure from food and feed uses. In e
valuating dietary exposure to S-metolachlor, EPA co
nsidered exposure under the petitioned-for tolerances as well as all existing S-metolachlor tolerances in 40 CFR 180.368. EPA assessed dietary exposures from S-metolachlor 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 co
ncern occurring as a result of a 1-day or single exposure.
Such effects were identified for S-metolachlor. In estimating acute dietary exposure, EPA used food co
nsumption information from the United States Department of Agriculture's (USDA) Natio
nal Health and Nutrition Examination Survey/What We Eat in America, (NHANES/WWEIA). As to residue levels in food, EPA assumed tolerance level residues and 100 percent crop treated (PCT).
ii. Chro
nic exposure. In co
nducting the chro
nic dietary exposure assessment EPA used the food co
nsumption data from the USDA's NHANES/WWEIA. As to residue levels in food, EPA assumed tolerance level residues and 100 PCT.
iii. Cancer. ba
sed on the data summarized in Unit III.A., EPA has co
ncluded that a no
nlinear RfD approach is appropriate for assessing cancer risk to S-metolachlor. Therefore, a separate quantitative cancer exposure assessment is unnecessary since the chro
nic dietary risk estimate will be protective of potential cancer risk.
iv. Anticipated residue and PCT information. EPA did not use anticipated residue or PCT information in the dietary assessment for S-metolachlor. Tolerance level residues and 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 S-metolachlor in drinking water. These simulation models take into account data on the physical, chemical, and fate/transport characteristics of S-metolachlor. 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.
The Agency assessed parent metolachlor, and the me
tabolites CGA-51202 (metolachlor-OA), CGA-40172, and CGA-50720 together in the drinking water assessment using a total toxic residues (TTR) approach wher half-lives were recalculated to collectively account for the parent and the combined residues of concern.
ba
sed on the Surface Water Co
ncentration Calculator (SWCC), the Pesticide Root Zone Model Ground Water (PRZM GW), and the Screening Co
ncentration in Ground Water (SCI-GROW), the estimated drinking water co
ncentrations (EDWCs) of S-metolachlor and its me
tabolites for acute exposures are estimated to be 371 parts per billion (ppb) for surface water and 1,060 ppb for ground water, and for chro
nic exposures are estimated to be 43.70 ppb for surface water and 14.3 ppb in ground water.
Modeled estimates of drinking water co
ncentrations were directly entered into the dietary exposure model. For acute dietary risk assessment, the water co
ncentration value of 1,060 ppb was used to assess the co
ntribution to drinking water. For chro
nic dietary risk assessment, the water co
ncentration of value 43.70 ppb was used to assess the co
ntribution to drinking water.
3. From non-dietary exposure. The term “residential exposure” is used in this docu
ment to refer to non-occupational, non-dietary exposure (e.g., for lawn and garden pest control, indoor pest control, termiticide, and flea and tick co
ntrol on pets).
S-metolachlor is currently registered for the following uses that could result in residential exposures: On commercial (sod farm) and residential warm-season turf grasses and other non-crop land including golf courses, sports fields, and ornamental gardens. EPA assessed residential exposure using the following assumptions: For residential handlers, short-term inhalation exposure isexpected. The following scenarios were e
valuated:
Mixing/loading/applying gardens/trees with manually-pressurized hand wand, hose-end sprayer, backpack, and sprinkler can equipment.
Mixing/loading/applying lawns/turf with manually-pressurized hand wand, hose-end sprayer, backpack, and sprinkler can equipment.
For residential post-application, there is the potential for short-term incidental oral exposure for individuals exposed as a result of being in an enviro
nment that has been previously treated with S-metolachlor. The quantitative exposure/risk assessment for residential post-application exposures is ba
sed on the following scenario:
Hand-to-mouth incidental oral exposure of children 1-2 years old playing on turf treated with S-metolachlor.
Further information regarding EPA standard assumptions and generic inputs for residential exposures may be found at http://www.epa.gov/pesticides/science/residential-exposure-sop.html.
4. Cumulative effects from substances with a common mechanism of toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when co
nsidering whether to establish, modify, or revoke a tolerance, the Agency co
nsider “available information” co
ncerning the cumulative effects of a particular pesticide's residues and “other substances that have a common mechanism of toxicity.”
EPA has not found S-metolachlor to share a common mechanism of toxicity with any other substances, and S-metolachlor does not appear to produce a toxic me
tabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has assumed that S-metolachlor 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 e
valuate the cumulative effects of such chemicals, see EPA's Web site at http://www.epa.gov/pesticides/cumulative.
D. Safety Factor for Infants and Children
1. In general. Section 408(b)(2)(C) of FFDCA provides that EPA shall apply an additio
nal tenfold (10×) margin of safety for infants and children in the case of threshold effects to account for prenatal and postnatal toxicity and the completeness of the databa
se on toxicity and exposure unless EPA determines ba
sed on reliable data that a different margin of safety will be safe for infants and children. This additio
nal margin of safety is commo
nly referred to as the Food Quality Protection Act Safety Factor (FQPA SF). In applying this provision, EPA either retains the default value of 10×, or uses a different additio
nal safety factor when reliable data available to EPA support the choice of a different factor.
2. Prenatal and postnatal sensitivity. There was no evidence of increased quantitative or qualitative fetal susceptibility in the prenatal developmental studies in rats and rabbits or in the reproductive toxicity study in rats, with either metolachlor or S-metolachlor. In general, significant developmental toxicity was not seen in rats or rabbits with either compound. The o
nly effects observed in fetal animals were in the rat prenatal developmental study and included slightly decreased number of implantations per dam, decreased number of live fetuses/dam, increased number of resorptions/dam and significant decrease in mean fetal bw. These effects occurred at maternally toxic doses (1,000 milligram/kilogram/day (mg/kg/day)).
3. Conclusion. EPA has determined that reliable data show the safety of infants and children would be adequately protected if the FQPA SF were reduced to 1× for all scenarios except inhalation. For inhalation scenarios a 10× databa
se uncertainty factor (UF) still applies. This decision is ba
sed on the following findings:
i. The toxicology databa
se for metolachlor and S-metolachlor is complete, with the exception of a required subchro
nic inhalation study for metolachlor. As noted above, a 10× data ba
se UF will be applied o
nly for assessing risk for inhalation exposure scenarios.
ii. There is no indication that S-metolachlor is a neurotoxic chemical and there is no need for a developmental neurotoxicity study or additio
nal UFs to account for neurotoxicity.
iii. There is no evidence that S-metolachlor results in increased susceptibility in in utero rats or rabbits in the prenatal developmental studies or in young rats in the 2-generation reproduction study.
iv. There are no residual uncertainties identified in the exposure databa
ses. The dietary food exposure assessments were performed ba
sed on 100 PCT and tolerance-level residues. EPA made co
nservative (protective) assumptions in the ground and surface water modeling used to assess exposure to S-metolachlor in drinking water. EPA used similarly co
nservative assumptions to assess post-application incidental oral exposure of children 1<2 years old. These assessments will not underestimate the exposure and risks posed by S-metolachlor.
E. Aggregate Risks and Determination of Safety
EPA determines whether acute and chro
nic dietary pesticide exposures are safe by comparing aggregate exposure estimates to the acute PAD (aPAD) and chro
nic PAD (cPAD). For linear cancer risks, EPA calculates the lifetime probability of acquiring cancer given the estimated aggregate exposure. Short-, intermediate-, and chronic-term risks are e
valuated by comparing the estimated aggregate food, water, and residential exposure to the appropriate PODs to ensure that an adequate MOE exists.
1. Acute risk. Using the exposure assumptions discussed in this unit for acute exposure, the acute dietary exposure from food and water to S-metolachlor will occupy 6.1% of the aPAD for all infants (less than 1 year old), the population group receiving the greatest exposure.
2. Chro
nic risk. Using the exposure assumptions described in this unit for chro
nic exposure, EPA has co
ncluded that chro
nic exposure to S-metolachlor from food and water will utilize 6.8% of the cPAD for children 1-2 years old, the population group receiving the greatest exposure. ba
sed on the explanation in Unit III.C.3., regarding residential use patterns, chro
nic residential exposure to residues of S-metolachlor is not expected.
3. Short-term risk. Short-term aggregate exposure takes into account short-term residential exposure plus chro
nic exposure to food and water (co
nsidered to be a background exposure level).
S-metolachlor is currently registered for uses that could result in short-term residential exposure, and the Agency has determined that it is appropriate to aggregate chro
nic exposure through food and water with short-term residential exposures to S-metolachlor. Potential short-term residential risk scenarios anticipated include adult inhalation handler exposure to turf via backpack sprayer and post-application incidental oral exposure of children playing on treated lawns.
Using the exposure assumptions described in this unit for short-term exposures, EPA has co
ncluded the combined short-term food, water, and residential exposures result in aggregate MOEs of 10,400 for adults and 1,100 for children 1-2 years old. Because EPA's levels of co
ncern for S-metolachlor is aMOE of 1,000 or below for inhalation scenarios (adults) and 100 or below for incidental oral scenarios (children 1-2 years old), these MOEs are not of concern.
4. Intermediate-term risk. Intermediate-term aggregate exposure takes into account intermediate-term residential exposure plus chro
nic exposure to food and water (co
nsidered to be a background exposure level).
An intermediate-term adverse effect was identified; however, S-metolachlor is not registered for any use patterns that would result in intermediate-term residential exposure. Because there is no intermediate-term residential exposure and chro
nic 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 chro
nic dietary risk assessment for e
valuating intermediate-term risk for S-metolachlor.
5. Aggregate cancer risk for U.S. population. As discussed in Unit III.A, the chro
nic dietary risk assessment is protective of any potential cancer effects. ba
sed on the results of that assessment, EPA co
ncludes that S-metolachlor is not expected to pose a cancer risk to humans.
6. Determination of safety. ba
sed on these risk assessments, EPA co
ncludes that there is a reaso
nable certainty that no harm will result to the general population, or to infants and children from aggregate exposure to S-metolachlor residues.
IV. Other Considerations
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A. Analytical Enforcement Methodology
Adequate methodology is available for enforcing the established and recommended tolerances. PAM Vol. II, Pesticide Regulation Section 180.368, lists a gas chromatography with nitrogen-phosphorus detector (GC/NPD) method (Method I) for determining residues in/on plant commodities and a gas chromatography with mass selecive detector (GC/MSD) method (Method II) for determining residues in livestock commodities. These methods determine residues of metolachlor and its me
tabolites as either CGA-37913 or CGA-49751 following acid hydrolysis. Adequate data are also available on the recovery of metolachlor through FDA's Multiresidue Method Testing Protocols which indicate that metolachlor is completely recovered through Method 302.
B. Internatio
nal Residue Limits
In making its tolerance decisions, EPA seeks to harmo
nize U.S. tolerances with internatio
nal standards whenever possible, co
nsistent with U.S. food safety standards and agricultural practices. EPA co
nsiders the internatio
nal 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 internatio
nal 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.
The Codex has not established a MRL for S-metolachlor.
C. Revisions to Petitioned-For Tolerances
The tolerance being established for the sunflower subgroup 20B is 1.0 ppm, not 0.50 ppm as proposed. This is due to the Agency using the Organization for Eco
nomic Cooperation and Development (OECD) Tolerance Calculation procedures, which determined that a tolerance of 1.0 ppm is appropriate ba
sed on entry of the 4 field trials for pre-emergence application.
V. Conclusion
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Therefore, tolerances are established for residues of S-metolachlor in or on lettuce at 1.5 ppm; the low growing berry subgroup 13-07G, except cranberry at 0.40 ppm; the sunflower subgroup 20B at 1.0 ppm; the vegetable, cucurbit group 9 at 0.50 ppm; and the vegetable, fruiting, group 8-10, except tabasco pepper at 0.10 ppm. Additionally, due to the establishment of the tolerances listed above, the existing tolerances for vegetable, fruiting, group 8, except tabasco pepper; cucumber; melon subgroup 9A; okra; pumpkin; squash, winter; and sunflower, seed are removed as they are unnecessary.