Pesticides; tolerances in food, animal feeds, and raw agricultural commodities: Quinoxyfen,

[Federal Register: August 25, 2006 (Volume 71, Number 165)]

[Rules and Regulations]

[Page 50350-50354]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr25au06-13]

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2006-0167; FRL-8088-8]

Quinoxyfen; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

SUMMARY: This regulation establishes tolerances for residues of quinoxyfen in or on commodities: lettuce, head and lettuce, leaf; melon, subgroup 9A; pepper, bell and pepper, nonbell; and strawberry. The Interregional Research Project Number 4 (IR-4) requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of 1996 (FQPA).

DATES: This regulation is effective August 25, 2006. Objections and requests for hearings must be received on or before October 24, 2006, 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: EPA has established a docket for this action under docket identification (ID) number EPA-HQ-OPP-2006-0167. All documents in the docket are listed in the index for the docket. Although listed in the index, some information is not publicly available, e.g., Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available in the electronic docket at http://www.regulations.gov, or,

if only available in hard copy, at the OPP Regulatory Public Docket in Rm. S-4400, One Potomac Yard (South Building), 2777 S. Crystal Drive, Arlington, VA. The Docket Facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The Docket telephone number is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: Sidney Jackson, Registration Division (7505P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone number: (703) 305-7610; e-mail address: jackson.sidney@epa.gov.

SUPPLEMENTARY INFORMATION:

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. Potentially affected entities may include, but are not limited to:

      Crop production (NAICS 111), e.g., agricultural workers; greenhouse, nursery, and floriculture workers; farmers.

      Animal production (NAICS 112), e.g., cattle ranchers and farmers, dairy cattle farmers, livestock farmers.

      Food manufacturing (NAICS 311), e.g., agricultural workers; farmers; greenhouse, nursery, and floriculture workers; ranchers; pesticide applicators.

      Pesticide manufacturing (NAICS 32532), e.g., agricultural workers; commercial applicators; farmers; greenhouse, nursery, and floriculture workers; residential users.

      This listing is not intended to be exhaustive, but rather provides a guide for readers regarding entities likely to be affected by this action. Other types of entities not listed in this unit could also be affected. The North American Industrial Classification System (NAICS) codes have been provided to assist you and others in determining whether this action might apply to certain entities. If you have any questions regarding the applicability of this action to a particular entity, consult the person listed under FOR FURTHER INFORMATION CONTACT.

   2. How Can I Access Electronic Copies of this Document?

      In addition to accessing an electronic copy of this Federal Register document through the electronic docket at http://www.regulations.gov , you may access this Federal Register document

      electronically through the EPA Internet under the ``Federal Register'' listings at http://www.epa.gov/fedrgstr. You may also access a

      frequently updated electronic version of 40 CFR part 180 through the Government Printing Office's pilot e-CFR site at http://www.gpoaccess.gov/ecfr. To access the OPPTS Harmonized Guidelines

      referenced in this document, go directly

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      to the guidelines at http://www.epa.gpo/opptsfrs/home/guidelin.htm

   3. Can I File an Objection or Hearing Request?

      Under section 408(g) of the FFDCA, as amended by the FQPA, any person may file an objection to any aspect of this regulation and may also request a hearing on those objections. The EPA procedural regulations which govern the submission of objections and requests for hearings appear in 40 CFR part 178. 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-2006-0167 in the subject line on the first page of your submission. All requests must be in writing, and must be mailed or delivered to the Hearing Clerk on or before October 24, 2006.

      In addition to filing an objection or hearing request with the Hearing Clerk as described in 40 CFR part 178, please submit a copy of the filing that does not contain any CBI for inclusion in the public docket that is described in ADDRESSES. Information not marked confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA without prior notice. Submit your copies, identified by docket ID number EPA-HQ-OPP-2006-0167, by one of the following methods:

      Federal eRulemaking Portal: http://www.regulations.gov.

      Follow the on-line instructions for submitting comments.

      Mail: Office of Pesticide Programs (OPP) Regulatory Public Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001.

      Delivery: OPP Regulatory Public Docket (7502P), Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South Building), 2777 S. Crystal Drive, Arlington, VA. Deliveries are only accepted during the Docket's normal hours of operation (8:30 a.m. to 4 p.m., Monday through Friday, excluding legal holidays). Special arrangements should be made for deliveries of boxed information. The Docket telephone number is (703) 305-5805.

2. Background and Statutory Findings

   In the Federal Register of April 21, 2006 (71 FR 20667) (FRL-8056- 4), EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C. 346a(d)(3), announcing the filing of pesticide petitions (PP 3E6755; 5E6969; and 5E6970) by the Interregional Research Project 4 (IR-4), 681 U.S. Highway 1 South, North Brunswick, NJ 08902-3390. The petitions requested that 40 CFR 180.588 be amended by establishing tolerances for residues of the fungicide quinoxyfen, (5,7-dichloro-4-(4-fluorophenoxy) quinoline in or on the raw agricultural commodities: eggplant at 1.0 parts per million (ppm) (PP 3E6755); peppers (bell and non-bell) at 1.0 ppm (PP 3E6755); melon subgroup 9A at 0.1 ppm (PP 5E6969); lettuce, head and leaf at 17.0 ppm (PP 5E6970); and strawberry at 0.8 ppm (PP 5E6970). That notice included a summary of the petition prepared by Dow AgroSciences, the registrant. There were no comments received in response to the notice of filing.

   Upon completing review of the current quinoxyfen database, the Agency concluded that the appropriate tolerance levels for quinoxyfen residues in or on pending crops should be established as follow: Lettuce, head at 7.0 ppm; lettuce, leaf at 19 ppm; melon, subgroup 9A at 0.08 ppm; pepper, bell at 0.35 ppm; pepper, non-bell at 1.7 ppm; and strawberry at 0.90 ppm. The Agency concluded that there are insufficient data to establish a tolerance for quinoxyfen residues in or on eggplant, at this time.

   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....''

   EPA performs a number of analyses to determine the risks from aggregate exposure to pesticide residues. For further discussion of the regulatory requirements of section 408 of the FFDCA and a complete description of the risk assessment process, see http://www.epa.gov/fedrgstr/EPA-PEST/1997/November/Day-26/p30948.htm .

3. Aggregate Risk Assessment and Determination of Safety

   Consistent with section 408(b)(2)(D) of FFDCA, 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, consistent with section 408(b)(2) of FFDCA, for a tolerance for residues of quinoxyfen on lettuce, head at 7.0 ppm; lettuce, leaf at 19 ppm; melon (subgroup 9A) at 0.08 ppm; pepper, bell at 0.35 ppm; pepper, non-bell at 1.7 ppm; and strawberry at 0.90 ppm. EPA's assessment of exposures and risks associated with establishing the tolerance 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. Specific information on the studies received and the nature of the toxic effects caused by quinoxyfen 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 in the Federal Register of September 29, 2003 (68 FR 55858) (FRL-7318-2), under docket ID number EPA-HQ-OPP-2003-0218, to which the reader may refer for additional information.

   2. Toxicological Endpoints

      For hazards that have a threshold below which there is no appreciable risk, the dose at which no adverse effects are observed (the NOAEL) from the toxicology study identified as appropriate for use in risk assessment is used to estimate the toxicological level of concern (LOC). However, the lowest dose at which adverse effects of concern are identified (the LOAEL) is sometimes used for risk assessment if no NOAEL was achieved in the toxicology study selected. An uncertainty factor (UF) is applied to reflect uncertainties inherent in the extrapolation from laboratory animal data to humans and in the variations in sensitivity among members of the human population as well as other unknowns.

      The linear default risk methodology (Q*) is the primary method currently used by the Agency to quantify non-threshold hazards such as cancer. The

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      Q* approach assumes that any amount of exposure will lead to some degree of cancer risk, estimates risk in terms of the probability of occurrence of additional cancer cases. More information can be found on the general principles EPA uses in risk characterization at http://www.epa.gov/pesticides/health/human.htm .

      A summary of the toxicological endpoints for quinoxyfen used for human risk assessment is discussed in Unit III.B. of the final rule published in the Federal Register of September 29, 2003 (68 FR 55858) (FRL-7318-2), under docket ID number EPA-HQ-OPP-2003-0218, to which the reader may refer for additional information.

   3. Exposure Assessment

      1. Dietary exposure from food and feed uses. Tolerances have been established (40 CFR 180.588) for the residues of quinoxyfen, in or on a variety of raw agricultural commodities. Permanent tolerances are established for residues of quinoxyfen per se in/on cherry, sweet and cherry, tart at 0.30 ppm; grape at 0.60 ppm; and dried hop cones at 3.0 ppm. In addition, time-limited tolerances are established under Section 18 emergency exemptions for residues of quinoxyfen per se in/on pumpkin; squash, winter; and vegetables, curcubit, subgroup 9A. Risk assessments were conducted by EPA to assess dietary exposures from quinoxyfen 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 one-day or single exposure.

         There were no toxic effects attributable to a single dose. Therefore, an endpoint of concern was not identified to quantitate acute-dietary risk to the general population or to the subpopulation females 13-50 years old. As a result, no acute risk is expected from exposure to quinoxyfen.

         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\TM\), Version 2.03, which incorporates food consumption data as reported by respondents in the USDA 1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by Individuals (CSFII), and accumulated exposure to the chemical for each commodity.

         The following assumptions were made for the chronic exposure assessments: An unrefined, Tier 1 chronic dietary (food and water) exposure assessment using tolerance-level residues and assuming 100% crops treated for all proposed commodities, and default DEEM Version 7.76 processing factors for all commodities.

         iii. Cancer. Quinoxyfen is classified as ``not likely to be carcinogenic to humans,'' based on the lack of evidence of carcinogenicity in rat and mice studies. Therefore, an exposure assessment for the purpose of evaluating cancer risk is not needed.

      2. Dietary exposure from drinking water. The Agency lacks sufficient monitoring exposure data to complete a comprehensive dietary exposure analysis and risk assessment for quinoxyfen in drinking water. Because the Agency does not have comprehensive monitoring data, drinking water concentration estimates are made by reliance on simulation or modeling taking into account data on the physical characteristics of quinoxyfen. Further information regarding EPA drinking water models used in pesticide exposure assessment can be found at http://www.epa.gov/oppefed1/models/water.

         Typically EPA evaluates the potential for human exposure to pesticides in drinking water through an assessment of available surface water and ground water monitoring data and modeling. For quinoxyfen, no monitoring data were available for use in this drinking water assessment. Therefore, potential human exposures to quinoxyfen were evaluated through modeling.

         The Agency used the FQPA Index Reservoir Screening Tool (FIRST) to calculate the surface water Estimated Exposure Concentrations (EECs) and the screening model SCI-GROW to calculate the groundwater EECs. The Agency considered residues of quinoxyfen per se, plus a metabolite, 3- OH quinoxyfen, in modeling studies. To do this, aerobic soil metabolism and aerobic aquatic metabolism half-lives determined for the parent compound in the guideline studies were recalculated using concentration data for the parent compound plus 3-OH quinoxyfen when the latter compound was present. Additionally, the Agency was restricted to the use of soil adsorption coefficients determined only for the parent compound; however, other available information from the guideline studies indicates that 3-OH quinoxyfen has mobility in soil similar to that of the parent compound. Because hydroxylation (the addition of the 3-OH) could increase its mobility relative to quinoxyfen, this metabolite has the potential to reach drinking water sources in significant quantities.

         For the surface water and groundwater assessments, EECs were determined using a maximum annual application rate for cherries of 0.55 lb a.i./A (five applications of 0.114 lb a.i./A/application).

         Based on the FIRST and SCI-GROW models, the estimated environmental concentrations (EECs) of quinoxyfen for chronic exposures are estimated to be 0.84 ppb for surface water and 0.006 ppb for ground water. Model estimates of drinking water concentrations were directly entered into the dietary exposure model (DEEM-FCID).

      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). Quinoxyfen is not registered for use on any sites that would result in residential exposure.

      4. Cumulative effects from substances with a common mechanism of toxicity. Section 408(b)(2)(D)(v) of the 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.''

         Unlike other pesticides for which EPA has followed a cumulative risk approach based on a common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as to quinoxyfen and any other substances and quinoxyfen does not appear to produce a toxic metabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has not assumed that quinoxyfen has 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 the policy statements released by EPA's Office of Pesticide Programs concerning common mechanism determinations and procedures for cumulating effects from substances found to have a common mechanism on EPA's website at http://www.epa.gov/pesticides/cumulative.

   4. Safety Factor for Infants and Children

      1. In general. Section 408 of FFDCA provides that EPA shall apply an additional tenfold margin of safety for infants and children in the case of threshold effects to account for prenatal

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         and postnatal toxicity and the completeness of the data base on toxicity and exposure unless EPA determines based on reliable data that a different margin of safety will be safe for infants and children. Margins of safety are incorporated into EPA risk assessments either directly through use of a MOE analysis or through using uncertainty (safety) factors in calculating a dose level that poses no appreciable risk to humans. In applying this provision, EPA either retains the default value of 10X when reliable data do not support the choice of a different factor, or, if reliable data are available, EPA uses a different additional safety factor value based on the use of traditional uncertainty factors and/or special FQPA safety factors, as appropriate.

      2. Prenatal and postnatal sensitivity. There is no quantitative or qualitative evidence of increased susceptibility of rat and rabbit fetuses to in utero exposure in developmental studies. There is evidence of increased quantitative susceptibility (minimal decrease in F1a pup weights) in the rat multi-generation reproduction study, but the concern is low since: (1) The effects in pups are well- characterized with a clear NOAEL; (2) the pup effects are minimal at the LOAEL and only noted in the first-generation offspring; and (3) the doses and endpoints selected for regulatory purposes would address the concerns of the pup effects noted in the rat reproduction study. Therefore, there are no residual uncertainties for prenatal/postnatal toxicity in this study.

      3. Conclusion. There is a complete toxicity data base for quinoxyfen and exposure data are complete or are estimated based on data that reasonably account for potential exposures. There are no residual uncertainties for prenatal/postnatal toxicity. No additional safety factor is needed for data base uncertainties. No clinical sign of neurotoxicity or neuropathology was seen in the data base, including acute and subchronic neurotoxicity studies. A developmental neurotoxicity study is not required. Therefore, EPA determined that the 10X SF to protect infants and children should be reduced to 1X.

   5. Aggregate Risks and Determination of Safety

      1. Acute risk. An endpoint of concern was not identified to quantitate acute-dietary risk to the general population or to the subpopulation females 13-50 years old. As a result, no acute risk is expected from exposure to quinoxyfen.

      2. Chronic risk. Using the exposure assumptions described in this unit for chronic exposure, EPA has concluded that exposure to quinoxyfen from (food + water) will utilize 1.3% of the cPAD for the U.S. population,