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Pyroxasulfone; Pesticide Tolerances

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Environmental Protection Agency (EPA).


Final rule.


This regulation establishes tolerances for residues of pyroxasulfone in or on multiple commodities which are identified and discussed later in this document. K-I Chemical U.S.A., Inc. requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA).


This regulation is effective July 31, 2013. Objections and requests for hearings must be received on or before September 30, 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).


The docket for this action, identified by docket identification (ID) number EPA-HQ-OPP-2012-0439 and EPA-HQ-OPP-2012-0514, is available at 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​dockets.

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Lois Rossi, Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460-0001; telephone number: (703) 305-7090; email address:

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I. General Information

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 document 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 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​cgi-bin/​text-idx?​&​c=​ecfr&​tpl=​/​ecfrbrowse/​Title40/​40tab_​02.tpl. To access the OCSPP test guidelines referenced in this document electronically, please go to​ocspp and select “Test Methods and Guidelines.”

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-2012-0439 and EPA-HQ-OPP-2012-0514 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 30, 2013. Addresses for mail and hand delivery of objections Start Printed Page 46275and 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-2012-0439 and EPA-HQ-OPP-2012-0514, by one of the following methods:

  • Federal eRulemaking Portal: Follow the online instructions for submitting comments. Do not submit electronically any information you consider to be CBI or other information whose disclosure is restricted by statute.
  • Mail: OPP Docket, Environmental 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​dockets/​contacts.htm.

Additional instructions on commenting or visiting the docket, along with more information about dockets generally, is available at​dockets.

II. Summary of Petitioned-For Tolerance

In the Federal Register of July 25, 2012 (77 FR 43562) (FRL-9353-6), 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 2F8026) by K-I Chemical U.S.A., Inc. The petition requested that 40 CFR 180.659 be amended by establishing tolerances for residues of the herbicide, pyroxasulfone (3-[(5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl) pyrazole-4-ylmethylsulfonyl]-4,5-dihydro-5,5-dimethyl-1,2-oxazole), in or on wheat, grain at 0.01 parts per million (ppm); pyroxasulfone (3-[(5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl) pyrazole-4-ylmethylsulfonyl]-4,5-dihydro-5,5-dimethyl-1,2-oxazole) and its metabolites M-1 (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1 H-pyrazol-4-ylmethanesulfonic acid) and M-25 (5-difluoromethoxy-3-trifluoromethyl-1 H-pyrazol-4-yl)methanesulfonic acid) calculated as the stoichiometric equivalent of pyroxasulfone, in or on wheat, straw at 0.6 ppm; [1] and pyroxasulfone (3-[(5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl) pyrazole-4-ylmethylsulfonyl]-4,5-dihydro-5,5-dimethyl-1,2-oxazole) and its metabolites M-1 (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1 H-pyrazol-4-ylmethanesulfonic acid), M-3 (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1 H-pyrazol-4-carboxylic acid), and M-25 (5-difluoromethoxy-3-trifluoromethyl-1 H-pyrazol-4-yl) methanesulfonic acid) calculated as the stoichiometric equivalent of pyroxasulfone in or on wheat, forage at 6.0 ppm and wheat, hay at 1.0 ppm.

Also, in the Federal Register of August 22, 2012 (77 FR 50661) (FRL-9358-9), 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 2F8042) by K-I Chemical U.S.A., Inc. The petition requested that 40 CFR 180.659 be amended by establishing tolerances for residues of the pyroxasulfone, (3-[(5-(difluoromethoxy)-1-methyl-3- (trifluoromethyl) pyrazole-4-ylmethylsulfonyl]-4,5-dihydro-5,5-dimethyl-1,2-oxazole) and its metabolite M-3 (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazol-4- carboxylic acid), in or on cotton seed at 0.01 ppm and pyroxasulfone (3-[(5-(difluoromethoxy)-1-methyl-3- (trifluoromethyl) pyrazole-4-ylmethylsulfonyl]-4,5-dihydro-5,5-dimethyl-1,2-oxazole) and its metabolite M-1 (5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazol-4- ylmethanesulfonic acid calculated as the stoichiometric equivalent of pyroxasulfone in or on cotton, gin byproducts at 0.2 ppm.

These documents referenced a summary of the petition prepared by K.I. Chemical U.S.A., Inc. the registrant, c/o Landis International, Inc., which is available in the associated dockets, There were no comments received in response to either of these notices of filing.

Based upon review of the data supporting the petition, EPA has increased the proposed tolerances for wheat, grain and cotton, undelinted seed and established a tolerance for milk. The reason for these changes are explained in Unit IV.C.

III. 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 pyroxasulfone including exposure resulting from the tolerances established by this action. EPA's assessment of exposures and risks associated with pyroxasulfone follows.

A. 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. Pyroxasulfone acute toxicity to mammals is low by all routes of exposure. Subchronic and chronic oral toxicity testing of pyroxasulfone in mice, rats, and dogs produced a variety of adverse effects in several target organs. Effects seen in animal studies included cardiac toxicity (increased cardiomyopathy in mice and rats), liver toxicity (centrilobular hepatocellular hypertrophy, histopathological, and/or clinical pathological indicators), neurotoxicity characterized by axonal/myelin degeneration in the sciatic nerve (dog, mouse, and rat) and spinal cord sections (dog), skeletal muscle myopathy, kidney Start Printed Page 46276toxicity (increased incidence of chronic progressive nephropathy in dogs and retrograde nephropathy in mice), urinary bladder mucosal hyperplasia, inflammation, and urinary bladder transitional cell papillomas (rats). Decreased body weight and enzyme changes were noted in some studies. Immunotoxicity studies in rats and mice showed no evidence of immunotoxic effects from pyroxasulfone. Pyroxasulfone was moderately toxic to rats following a 4-week dermal exposure producing local inflammation and systemic effects of minimal to mild cardiac myofiber degeneration at the limit dose. No adverse effects were noted in a 28-day inhalation study at the highest-dose tested. Pyroxasulfone did not exhibit developmental toxicity in the rat and exhibited only slight developmental toxicity in rabbits (reduced fetal weight and resorptions) at the limit dose. However, developmental effects were noted in post-natal day (PND) 21 offspring in the rat developmental neurotoxicity (DNT) study characterized as decreased brain weight and morphometric changes. Developmental effects in the rabbit developmental study and DNT study occurred in the absence of maternal toxicity, indicating potential increased quantitative susceptibility of offspring. In a reproductive toxicity in rats reduced pup weight and body weight gains during lactation occurred at similar or higher doses causing pronounced maternal toxicity (reduced body weight, body weight gain, and food consumption and increased kidney weight, cardiomyopathy, and urinary bladder mucosal hyperplasia with inflammation). In cancer studies in mice and rats, renal tubular adenomas were observed in male mice and urinary bladder transitional cell papillomas were observed in male rats. The kidney adenomas in male mice were determined to be spontaneous and not treatment-related based on the following considerations:

1. Absence of any cytotoxicity (degeneration or individual cell necrosis) in studies ranging from 14 days to 18 months at doses up to 15,000 ppm.

2. Absence of cell regeneration leading to precursor lesions such as atypical tubular hyperplasia at all time points and doses up to 15,000 ppm.

3. Lack of exacerbation of chronic progressive nephropathy, a spontaneous disease in rodents that results in cell regeneration which can result in renal tubule tumors in chronic studies.

4. Lack of a clear dose response in the distribution of tumors between test substance treated groups.

The urinary bladder tumors seen in male rats were determined to be a threshold effect. Pyroxasulfone exposure causes the growth of crystals in the urinary tract with subsequent calculi formation resulting in cellular damage. Crystal formation in the absence of calculi is not associated with hyperplasia or urinary bladder tumors; therefore, the formation of urinary bladder calculi is the prerequisite for subsequent hyperplasia and neoplasia. In other words, urinary bladder tumors do not develop at doses too low to produce calculi. There is also a clear threshold of 1,000 ppm (42.55 milligrams/kilogram/day (mg/kg/day)) for development of calculi and tumorigenesis. The point of departure (POD) of 50 ppm (2.0 mg/kg/day) selected for chronic risk assessment is not expected to result in urinary bladder calculi formation, which is a prerequisite for subsequent hyperplasia and neoplasia. Therefore, the Agency has determined that the quantification of risk using a non-linear approach (i.e., Reference dose (RfD)) will adequately account for all chronic toxicity, including carcinogenicity, that could result from exposure to pyroxasulfone. There is no concern for mutagenicity.

Specific information on the studies received and the nature of the adverse effects caused by pyroxasulfone 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 in document “Pyroxasulfone Human Health Risk Assessment for Use of Pyroxasulfone on Wheat and Cotton,” p. 36 in docket ID numbers EPA-HQ-OPP-2012-0439 and EPA-HQ-OPP-2012-0514.

B. 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 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​pesticides/​factsheets/​riskassess.htm.

A summary of the toxicological endpoints for pyroxasulfone used for human risk assessment is discussed in Unit III.B. of the final rule published in the Federal Register of February 29, 2012 (77 FR 12207) (FRL-9334-2).

C. Exposure Assessment

1. Dietary exposure from food and feed uses. In evaluating dietary exposure to pyroxasulfone, EPA considered exposure under the petitioned-for tolerances as well as all existing pyroxasulfone tolerances in 40 CFR 180.659. EPA assessed dietary exposures from pyroxasulfone 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 pyroxasulfone. In estimating acute dietary exposure, EPA used food consumption information from the U.S. Department of Agriculture's National Health and Nutrition Examination Survey, What We Eat in America, (NHANES/WWEIA). As to residue levels in food, EPA assumed 100 percent crop treated (PCT) at tolerance-level residues adjusted upward to account for metabolites which are not in the tolerance expression from specific use patterns.

ii. Chronic exposure. In conducting the chronic dietary exposure assessment EPA used the food consumption data from the U.S. Department of Agriculture's NHANES/WWEIA. As to residue levels in food, EPA made the same assumptions (adjusted tolerance-level residues and 100 PCT) as in the acute dietary exposure assessment.

iii. Cancer. EPA determines whether quantitative cancer exposure and risk assessments are appropriate for a food-use pesticide based on the weight of the evidence from cancer studies and other relevant data. Cancer risk is quantified using a linear or nonlinear approach. If sufficient information on the carcinogenic mode of action is available, Start Printed Page 46277a threshold or nonlinear approach is used and a cancer RfD is calculated based on an earlier noncancer key event. If carcinogenic mode of action data are not available, or if the mode of action data determines a mutagenic mode of action, a default linear cancer slope factor approach is utilized. Based on the data summarized in Unit III.A., EPA has concluded that a nonlinear RfD approach is appropriate for assessing cancer risk to pyroxasulfone. Cancer risk was assessed using the same exposure estimates as discussed in Unit III.C.1.ii.

iv. Anticipated residue and PCT information. EPA did not use anticipated residue and/or PCT information in the dietary assessment for pyroxasulfone. Adjusted 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 pyroxasulfone in drinking water. These simulation models take into account data on the physical, chemical, and fate/transport characteristics of pyroxasulfone. Further information regarding EPA drinking water models used in pesticide exposure assessment can be found at​oppefed1/​models/​water/​index.htm.

Based on the Pesticide Root Zone Model/Exposure Analysis Modeling System (PRZM/EXAMS) and Pesticide Root Zone Model Ground Water (PRZM GW), the estimated drinking water concentrations (EDWCs) of pyroxasulfone for acute exposures are estimated to be 17 parts per billion (ppb) for surface water and 210 ppb for ground water. EDWCs of pyroxasulfone for chronic exposures for non-cancer assessments are estimated to be 3.2 ppb for surface water and 174 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 210 ppb was used to assess the contribution to drinking water. For chronic dietary risk assessment, the water concentration of value 174 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). Pyroxasulfone is not registered for any specific use patterns that would result in residential exposure.

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 pyroxasulfone to share a common mechanism of toxicity with any other substances, and pyroxasulfone does not appear to produce a toxic metabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has assumed that pyroxasulfone 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​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 additional tenfold (10X) 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 database on toxicity and exposure unless EPA determines based on reliable data that a different margin of safety will be safe for infants and children. This additional margin of safety is commonly referred to as the FQPA Safety Factor (SF). In applying this provision, EPA either retains the default value of 10X, or uses a different additional safety factor when reliable data available to EPA support the choice of a different factor.

2. Prenatal and postnatal sensitivity. The pre-natal and post-natal toxicity database for pyroxasulfone includes developmental toxicity studies in rats and rabbits, a DNT study in rats, and a 2-generation reproduction toxicity study in rats. As discussed in Unit III.A., evidence of increased susceptibility of fetuses and offspring was seen in the DNT study and developmental toxicity study in rabbits following in utero or post-natal exposure to pyroxasulfone. No increased susceptibility was seen in the rat developmental or reproduction toxicity studies. In rabbits, developmental toxicity was only seen at the limit dose of 1,000 mg/kg/day as reduced fetal weight and increased fetal resorptions with a NOAEL of 500 mg/kg/day for these effects, compared to no maternal toxicity at these doses. In a DNT study in rats, offspring toxicity (decreased brain weight and morphometric changes on PND 21) was seen at 300 mg/kg/day compared to no maternal toxicity at 900 mg/kg/day. The degree of concern for the increased susceptibility seen in these studies is low and there are no residual uncertainties based on the following considerations:

i. The increased susceptibility is occurring at high doses.

ii. NOAELs and LOAELs have been identified for all effects of concern, and thus a clear dose response has been well defined.

iii. The PODs selected for risk assessment are protective of the fetal/offspring effects.

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 1x. That decision is based on the following:

i. The toxicity database for pyroxasulfone is complete.

ii. Pyroxasulfone is a neurotoxic chemical and there is evidence of increased susceptibility of offspring with regard to neurotoxic effects in the rat DNT study. There is also evidence of increased susceptibility of fetuses/offspring with regard to non-neurotoxic effects in the rabbit developmental toxicity study. However, the concern for the increased susceptibility is low for the reasons stated in Unit III.D.2.; therefore, EPA determined that a 10X FQPA safety factor is not necessary to protect infants and children.

iii. There are no residual uncertainties identified in the exposure databases. The dietary food exposure assessments were performed based on 100 PCT and adjusted tolerance-level residues. EPA made conservative (protective) assumptions in the ground and surface water modeling used to assess exposure to pyroxasulfone in drinking water. These assessments will not underestimate the exposure and risks posed by pyroxasulfone.

E. Aggregate Risks and Determination of Safety

EPA determines whether acute and chronic dietary pesticide exposures are safe by comparing aggregate exposure estimates to the acute PAD (aPAD) and chronic 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 evaluated by comparing the estimated aggregate food, water, and residential exposure to the appropriate Start Printed Page 46278PODs 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 pyroxasulfone will occupy 3.6% of the aPAD for all infants (< 1-year-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 pyroxasulfone from food and water will utilize 48% of the cPAD for all infants (< 1-year-old) the population group receiving the greatest exposure. There are no residential uses for pyroxasulfone.

3. Short- and intermediate-term risk. Short- and intermediate-term aggregate exposure takes into account short- and intermediate-term residential exposure plus chronic exposure to food and water (considered to be a background exposure level). Short- and intermediate-term adverse effects were identified; however, pyroxasulfone is not registered for any use patterns that would result in short- or intermediate-term residential exposure. Because there is no short- or 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 short- and intermediate-term risk), no further assessment of short- or intermediate-term risk is necessary, and EPA relies on the chronic dietary risk assessment for evaluating short- and intermediate-term risk for pyroxasulfone.

4. Aggregate cancer risk for U.S. population. As explained in Unit III.A., the Agency has determined that the quantification of risk using a non-linear (i.e., RfD) approach will adequately account for all chronic toxicity, including carcinogenicity, that could result from exposure to pyroxasulfone. Therefore, based on the results of the chronic risk assessment discussed in Unit III.E.2., pyroxasulfone is not expected to pose a cancer risk to humans.

6. Determination of safety. Based on these risk assessments, EPA concludes that there is a reasonable certainty that no harm will result to the general population or to infants and children from aggregate exposure to pyroxasulfone residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

Adequate enforcement methodology (a liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) method) is available to enforce the tolerance expression. The method 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:

B. International Residue Limits

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.

The Codex has not established a MRL for pyroxasulfone.

C. Revisions to Petitioned-For Tolerances

EPA has increased the proposed tolerance levels for wheat, grain from 0.01 ppm to 0.03 ppm and cotton, undelinted seed from 0.01 ppm to 0.04 ppm. The increase in these two tolerance levels are due to the use of the Organization for Economic Cooperation and Development tolerance calculation procedures, inclusion of different metabolites of concern, significant figures, and use of all residue field trials. The proposed commodity term, “cotton, seed” is being revised to “cotton, undelinted seed.”

Additionally, EPA is establishing a tolerance for pyroxasulfone in milk as a result of the increased livestock burden from use of pyroxasulfone on wheat and cotton commodities.

V. Conclusion

Therefore, tolerances are established for residues of pyroxasulfone, 3-[[[5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1 H-pyrazol-4-yl]methyl]sulfonyl]-4,5-dihydro-5,5-dimethylisoxazole, including its metabolites and degradates, as set forth in the regulatory text.

VI. Statutory and Executive Order Reviews

This final rule establishes tolerances under FFDCA section 408(d) in response to a petition submitted to the Agency. The Office of Management and Budget (OMB) has exempted these types of actions from review under Executive Order 12866, entitled “Regulatory Planning and Review” (58 FR 51735, October 4, 1993). Because this final rule has been exempted from review under Executive Order 12866, this final rule is not subject to Executive Order 13211, entitled “Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use” (66 FR 28355, May 22, 2001) or Executive Order 13045, entitled “Protection of Children From Environmental Health Risks and Safety Risks” (62 FR 19885, April 23, 1997). This final rule does not contain any information collections subject to OMB approval under the Paperwork Reduction Act (PRA) (44 U.S.C. 3501 et seq.), nor does it require any special considerations under Executive Order 12898, entitled “Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Populations” (59 FR 7629, February 16, 1994).

Since tolerances and exemptions that are established on the basis of a petition under FFDCA section 408(d), such as the tolerance in this final rule, do not require the issuance of a proposed rule, the requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et seq.), do not apply.

This final rule directly regulates growers, food processors, food handlers, and food retailers, not States or tribes, nor does this action alter the relationships or distribution of power and responsibilities established by Congress in the preemption provisions of FFDCA section 408(n)(4). As such, the Agency has determined that this action will not have a substantial direct effect on States or tribal governments, on the relationship between the national government and the States or tribal governments, or on the distribution of power and responsibilities among the various levels of government or between the Federal Government and Indian tribes. Thus, the Agency has determined that Executive Order 13132, entitled “Federalism” (64 FR 43255, August 10, 1999) and Executive Order 13175, entitled “Consultation and Coordination With Indian Tribal Governments” (65 FR 67249, November 9, 2000) do not apply to this final rule. In addition, this final rule does not impose any enforceable duty or contain any Start Printed Page 46279unfunded mandate as described under Title II of the Unfunded Mandates Reform Act of 1995 (UMRA) (2 U.S.C. 1501 et seq.).

This action does not involve any technical standards that would require Agency consideration of voluntary consensus standards pursuant to section 12(d) of the National Technology Transfer and Advancement Act of 1995 (NTTAA) (15 U.S.C. 272 note).

VII. Congressional Review Act

Pursuant to the Congressional Review Act (5 U.S.C. 801 et seq.), EPA will submit a report containing this rule and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of the rule in the Federal Register. This action is not a “major rule” as defined by 5 U.S.C. 804(2).

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List of Subjects in 40 CFR Part 180

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Dated: July 25, 2013.

Lois Rossi,

Director, Registration Division, Office of Pesticide Programs.

End Signature

Therefore, 40 CFR chapter I is amended as follows:

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1. The authority citation for part 180 continues to read as follows:

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Authority: 21 U.S.C. 321(q), 346a and 371.

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2. Section 180.659 is amend by:

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i. Adding alphabetically the following commodities to the table in paragraph (a)(1);

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ii. Adding alphabetically the following commodities to the table in paragraph (a)(2); and

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iii. Adding paragraph (a)(4).

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The additions read as follows:

Pyroxasulfone; tolerances for residues.

(a) * * *

(1) * * *

CommodityParts per million
*    *    *    *    *
Cotton, undelinted seed0.04
Wheat, grain0.03

(2) * * *

CommodityParts per million
Cotton, gin byproducts0.20
*    *    *    *    *
Wheat, forage6.0
Wheat, hay1.0
Wheat, straw0.60
* * * * *

(4) Tolerances are established for residues of the herbicide pyroxasulfone, including its metabolites and degradates, in or on the commodities in the following table. Compliance with the tolerance levels specified in the following table is to be determined by measuring only the sum of pyroxasulfone [3-[[[5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl]methyl]sulfonyl]-4,5-dihydro-5,5-dimethylisoxazole] and its metabolites [5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl]methanesulfonic acid (M-1) and 5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-carboxylic acid (M-3), calculated as the stoichiometric equivalent of pyroxasulfone, in or on the commodity.

CommodityParts per million
* * * * *
End Supplemental Information



EPA's July 25, 2012 notification of the requested tolerance contained an error. It stated that petitioners requested a tolerance of the parent pyroxasulfone and the M-1 and M-25 metabolites on “wheat, grain at 0.6 ppm” instead of “wheat, straw at 0.6 ppm” as the petitioners requested. To address the error and provide notice of requested tolerance, EPA issued a correction. See 77 FR 59577; FRL-9364-3 (Sept. 28, 2012). Back to Citation

[FR Doc. 2013-18412 Filed 7-30-13; 8:45 am]