Penoxsulam; Pesticide Tolerances


Federal Register, Volume 81 Issue 41 (Wednesday, March 2, 2016)

Federal Register Volume 81, Number 41 (Wednesday, March 2, 2016)

Rules and Regulations

Pages 10771-10776

From the Federal Register Online via the Government Publishing Office

FR Doc No: 2016-04598




40 CFR Part 180

EPA-HQ-OPP-2014-0879; FRL-9940-36

Penoxsulam; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.


SUMMARY: This regulation establishes tolerances for residues of penoxsulam in or on multiple commodities which are identified and discussed later in this document. Interregional Research Project Number 4 (IR-4) requested these tolerances associated with pesticide petition number (PP#) 4E8330, under the Federal Food, Drug, and Cosmetic Act (FFDCA).

DATES: This regulation is effective March 2, 2016. Objections and requests for hearings must be received on or before May 2, 2016, and must be filed in accordance with the instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).

ADDRESSES: The docket for this action, identified by docket identification (ID) number EPA-HQ-OPP-2014-0879, is available at or at the Office of Pesticide Programs Regulatory Public Docket (OPP Docket) in the Environmental Protection Agency Docket Center (EPA/DC), West William Jefferson Clinton 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

FOR FURTHER INFORMATION CONTACT: Susan Lewis, Registration Division (7505P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460-0001; main telephone number: (703) 305-7090; email address:


  1. General Information

    1. 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).

    2. 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

    3. 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-2014-0879 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 May 2, 2016. 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-2014-0879, 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

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

  2. Summary of Petitioned-For Tolerance

    In the Federal Register of March 4, 2015 (80 FR 11611) (FRL-9922-

    68), EPA issued a document pursuant to FFDCA section 408(d)(3), 21 U.S.C.

    Page 10772

    346a(d)(3), announcing the filing of a pesticide petition (PP#) 4E8330 by Interregional Research Project Number 4 (IR-4), 500 College Road East, Princeton, NJ 08540. The petition requested that 40 CFR 180.605 be amended by establishing tolerances for residues of the herbicide penoxsulam, (2-(2,2-difluoroethoxy)-N-(5,8-dimethoxy1,2,4 triazolo1,5-cpyrimidin-2-yl)-6-(trifluoromethyl)benzenesulfonamide), in or on fruit, pome, group 11-10 at 0.01 parts per million (ppm); fruit, stone, group 12-12 at 0.01 ppm; fruit, small, vine climbing, subgroup 13-07F, except fuzzy kiwifruit at 0.01 ppm; nut, tree, group 14-12 at 0.01 ppm; olive at 0.01 ppm; and pomegranate at 0.01 ppm. In addition, the petitioner proposed removal of existing tolerances on grape; nut, tree, group 14; and pistachio as they are superseded by this rule. That document referenced a summary of the petition prepared on behalf of IR-4 by Dow AgroSciences LLC, the registrant, which is available in the docket EPA-HQ-OPP-2014-0879 at There were no comments received in response to the notice of filing.

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

    1. Toxicological Profile

      EPA has evaluated the available toxicity data and considered their 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.

      In subchronic and chronic feeding studies in rats and dogs, the kidney was the most sensitive target organ. Hyperplasia of the renal pelvic epithelium was observed in both species, and in the rat, effects on renal function and increased severity of chronic glomerulonephropathy were also observed following chronic exposure. Effects on the liver, hematological parameters, and body weight were observed sporadically in some studies. In subchronic and chronic feeding studies in mice, no effects of toxicological significance were observed.

      There was no evidence of increased quantitative or qualitative susceptibility of fetuses or offspring, as compared to adults. In developmental toxicity studies in rats and rabbits, no developmental toxicity was observed at maternally toxic dose levels. In a 2-

      generation reproduction study in rats, delays in preputial separation were noted in the presence of parental toxicity. No treatment-related neurotoxicity or immunotoxicity were observed in any of the available studies on penoxsulam. No systemic or dermal toxicity was noted in a 28-day dermal toxicity study in rats.

      Although an increased incidence of mononuclear cell leukemia (MNCL) was observed in a chronic toxicity/carcinogenicity study in Fisher 344 rats, EPA determined that human cancer risk is likely to be minimal and is not conducting a separate quantitative cancer assessment for the following reasons: (1) Lack of a dose-response, suggesting that the tumor may not be treatment-related; (2) the tumors were found in only one gender and one species (they were not found in female rats or mice); (3) the tumors are of questionable relevance to humans since there is no similar tumor occurring in humans; (4) penoxsulam is negative for mutagenicity; and (5) MNCL is not associated with exposure to other triazolopyrimidines, which is the chemical class of herbicides to which penoxsulam belongs. Therefore, based on the current (2005) Agency guidelines for cancer assessment, EPA has determined that the chronic assessment will be protective of any potential cancer risks.

      Specific information on the studies received and the nature of the adverse effects caused by penoxsulam 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, ``Penoxsulam. Human Health New Use Risk Assessment to Support the Registration of Proposed Use on Pome Fruit, Stone Fruit, Olive, Pomegranate, and Fruit, Small, Vine Climbing (Subgroup 13-07F, Except Fuzzy Kiwifruit); and Crop Group Conversion for Tree Nuts'' on pages 10-16 in docket ID number EPA-HQ-OPP-2014-


    2. 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

      A summary of the toxicological endpoints for penoxsulam used for human risk assessment is shown in Table 1 of this unit.

      Page 10773

      Table 1--Summary of Toxicological Doses and Endpoints for Penoxsulam for Use in Human Health Risk Assessment


      Point of departure and

      Exposure/scenario uncertainty/safety RfD, PAD, LOC for risk Study and toxicological effects

      factors assessment


      Acute dietary (All Populations, No toxicological endpoint attributable to a single exposure was identified in the available toxicology studies on

      including Infants and Children and penoxsulam. This exposure scenario was therefore not assessed for human health risk.

      Females 13-49 years of age).


      Chronic dietary (All populations). NOAEL = 14.7 mg/kg/day. Chronic RfD = 0.147 mg/ 1 Year Chronic Feeding Study in Dogs.

      UFA = 10 x............. kg/day. LOAEL = 46.2 mg/kg/day based on multifocal hyperplasia of the

      UFH = 10 x............. cPAD = 0.147 mg/kg/day. renal pelvic epithelium.

      FQPA SF = 1x...........

      Incidental oral short-term (1 to 30 NOAEL= 17.8 mg/kg/day.. LOC for MOE = 100...... 13-Week Feeding Study in Dogs.

      days). UFA = 10 x............. LOAEL = 49.4 mg/kg/day based on multifocal hyperplasia of the

      UFH = 10 x............. renal pelvic epithelium and crystals in the renal pelvis and

      FQPA SF = 1x........... collecting ducts.


      Dermal (All Durations). An endpoint for systemic toxicity was not identified in the rat 28-day dermal study and there were no neurotoxic,

      developmental, or immunotoxic effects observed for penoxsulam. This exposure scenario was not assessed for human

      health risk.


      Inhalation Short-Term (1 to 30 days) NOAEL= 17.8 mg/kg/day.. LOC for MOE = 100...... 13-Week Feeding Study in Dogs.

      and Intermediate-Term (1 to 6 UFA = 10 x............. LOAEL = 49.4 mg/kg/day based on multifocal hyperplasia of the

      months). UFH = 10 x............. renal pelvic epithelium and crystals in the renal pelvis and

      FQPA SF = 1x........... collecting ducts.


      Cancer (Oral, dermal, inhalation). Classification: A separate quantitative cancer assessment is not being conducted as the cRfD is considered

      protective of potential carcinogenic 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. UFA = extrapolation from animal to human (interspecies). UFH = potential variation in sensitivity among

      members of the human population (intraspecies).

    3. Exposure Assessment

      1. Dietary exposure from food and feed uses. In evaluating dietary exposure to penoxsulam, EPA considered exposure under the petitioned-

      for tolerances as well as all existing penoxsulam tolerances in 40 CFR 180.605. EPA assessed dietary exposures from penoxsulam 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. No such effects were identified in the toxicological studies for penoxsulam; therefore, a quantitative acute dietary exposure assessment is unnecessary.

      ii. Chronic exposure. In conducting the chronic dietary exposure assessment EPA used the Dietary Exposure Evaluation Model software with the Food Commodity Intake Database (DEEM-FCID) Version 3.16. This software uses 2003-2008 food consumption data from the U.S. Department of Agriculture's (USDA's) National Health and Nutrition Examination Survey, What We Eat in America, (NHANES/WWEIA). As to residue levels in food, EPA tolerance-level residues, 100 percent crop treated (PCT) for all commodities, and DEEM (Version 7.81) default processing factors.

      iii. Cancer. Based on the data summarized in Unit III.A., EPA has concluded that the chronic assessment for penoxsulam is considered protective of potential cancer risks. Therefore, a separate dietary exposure assessment for the purpose of assessing cancer risk is unnecessary.

      iv. Anticipated residue and percent crop treated (PCT) information. EPA did not use anticipated residue and/or PCT information in the dietary assessment for penoxsulam. Tolerance-level residues and/or 100 PCT were assumed for all food commodities.

      2. Dietary exposure from drinking water. In drinking water, the residues of concern include penoxsulam parent, along with the following degradates: BSTCA; 2-amino TCA; 5-OH-penoxsulam; SFA; sulfonamide; and 5,8-diOH. The Agency used screening-level water exposure models in the dietary exposure analysis and risk assessment for penoxsulam in drinking water. These simulation models take into account data on the physical, chemical, and fate/transport characteristics of penoxsulam. Further information regarding EPA drinking water models used in pesticide exposure assessment can be found at

      Penoxsulam is registered for control of aquatic weeds. For that use pattern, the maximum application rate is 150 parts per billion (ppb) in the water column. For chronic dietary risk assessment, the water concentration value of 150 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).

      Penoxsulam is currently registered for the following uses that could result in residential exposures: Residential and commercial turf (lawns and golf courses) and aquatic use sites. EPA assessed residential exposure using the following assumptions: For handlers, it is assumed that residential use will result in short-term (1 to 30 days) duration dermal and inhalation exposures. Residential post-

      application exposure is also assumed to be short-term (1-30 days) in duration, resulting from the following exposure scenarios:

      Physical activities on turf: Adults (dermal) and children 1-2 years old (dermal and incidental oral);

      mowing turf: Adults (dermal) and children 11 to exposure to golf courses during golfing: Adults (dermal), children 11 to exposure during aquatic activities (e.g. swimming): Adults (dermal, inhalation, ingestion) and children 3 to