99-23194. Avermectin BINF1/INF and its delta-8,9-isomer; Pesticide Tolerance  

  • [Federal Register Volume 64, Number 172 (Tuesday, September 7, 1999)]
    [Rules and Regulations]
    [Pages 48548-48560]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 99-23194]
    
    
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    ENVIRONMENTAL PROTECTION AGENCY
    
    40 CFR Part 180
    
    [OPP-300916; FRL-6380-7]
    RIN 2070-AB78
    
    
    Avermectin B1 and its delta-8,9-isomer; Pesticide 
    Tolerance
    
    AGENCY: Environmental Protection Agency (EPA).
    ACTION: Final rule.
    
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    SUMMARY: This regulation establishes a tolerance for combined residues 
    of the insecticide avermectin B1 (a mixture of avermectins 
    containing greater than or equal to 80% avermectin B1a (5-O-
    demethyl avermectin A1) and less than or equal to 20% 
    avermectin B1b (5-O-demethyl-25-de(1-methylpropyl)-25-(1-
    methylethyl) avermectin A1)) and its delta-8,9-isomer in or 
    on grapes at 0.02 parts per million (ppm), peppers at 0.02 ppm, and 
    cotton gin byproducts at 0.15 ppm; makes permanent tolerances for 
    citrus, hops, potatoes, meat and meat by-products, milk, and cotton 
    seed which were previously time limited (expiring September 1, 1999); 
    and clarifies that permanent tolerances have previously been 
    established for almond hulls at 0.10 ppm and wet apple pomace at 0.10 
    ppm. Novartis Crop Protection, Inc. requested these tolerance actions 
    under the Federal Food, Drug, and Cosmetic Act, as amended by the Food 
    Quality Protection Act of 1996.
    DATES: This regulation is effective September 7, 1999. Objections and 
    requests for hearings, identified by docket control number OPP-300916, 
    must be received by EPA on or before November 8, 1999.
    ADDRESSES:  Written objections and hearing requests may be submitted by 
    mail, in person, or by courier. Please follow the detailed instructions 
    for each method as provided in Unit VI. of the ``SUPPLEMENTARY 
    INFORMATION'' section. To ensure proper receipt by EPA, your objections 
    and hearing requests must identify docket control number OPP-300916 in 
    the subject line on the first page of your response.
    FOR FURTHER INFORMATION CONTACT: By mail: Thomas C. Harris, 
    Registration Division (7505C), Office of Pesticide Programs, 
    Environmental Protection Agency, 401 M St., SW., Washington, DC 20460; 
    telephone number: (703) 308-9423; and e-mail address: 
    harris.thomas@epa.gov.
     SUPPLEMENTARY INFORMATION:
    
     I. General Information
    
    A. Does this Action Apply to Me?
    
        You may be affected by this action if you are an agricultural 
    producer, food manufacturer, or pesticide manufacturer. Potentially 
    affected categories and entities may include, but are not limited to:
    
    ------------------------------------------------------------------------
                                                     Examples of Potentially
                  Categories                NAICS       Affected Entities
    ------------------------------------------------------------------------
    Industry                                   111  Crop production
                                               112  Animal production
                                               311  Food manufacturing
                                             32532  Pesticide manufacturing
    ------------------------------------------------------------------------
    
        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 the table could also be 
    affected. The North American Industrial Classification System
    
    [[Page 48549]]
    
    (NAICS) codes have been provided to assist you and others in 
    determining whether or not this action might apply to certain entities. 
    If you have questions regarding the applicability of this action to a 
    particular entity, consult the person listed in the ``FOR FURTHER 
    INFORMATION CONTACT'' section.
    
    B. How Can I Get Additional Information, Including Copies of this 
    Document and Other Related Documents?
    
        1. Electronically.You may obtain electronic copies of this 
    document, and certain other related documents that might be available 
    electronically, from the EPA Internet Home Page at http://www.epa.gov/. 
    To access this document, on the Home Page select ``Laws and 
    Regulations'' and then look up the entry for this document under the 
    ``Federal Register--Environmental Documents.'' You can also go directly 
    to the Federal Register listings at http://www.epa.gov/fedrgstr/.
        2. In person. The Agency has established an official record for 
    this action under docket control number OPP-300916. The official record 
    consists of the documents specifically referenced in this action, and 
    other information related to this action, including any information 
    claimed as Confidential Business Information (CBI). This official 
    record includes the documents that are physically located in the 
    docket, as well as the documents that are referenced in those 
    documents. The public version of the official record does not include 
    any information claimed as CBI. The public version of the official 
    record, which includes printed, paper versions of any electronic 
    comments submitted during an applicable comment period is available for 
    inspection in the Public Information and Records Integrity Branch 
    (PIRIB), Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy., 
    Arlington, VA, from 8:30 a.m. to 4 p.m., Monday through Friday, 
    excluding legal holidays. The PIRIB telephone number is (703) 305-5805.
    
    II. Background and Statutory Findings
    
        This regulation addresses three tolerance actions concerning 
    avermectin B1 and its delta-8,9-isomer.
    
    A. New Tolerances
    
        In the Federal Register of August 11, 1997 (62 FR 42980) (FRL-5736-
    1), EPA issued a notice pursuant to section 408 of the Federal Food, 
    Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a as amended by the Food 
    Quality Protection Act of 1996 (FQPA) (Public Law 104-170) announcing 
    the filing of a pesticide petition (PP 7F4844) for tolerance by Merck 
    Research Laboratories, PO Box 450, Hillsborough Rd, Three Bridges, NJ. 
    The petition was later transferred to Novartis Crop Protection, Inc., 
    PO Box 18300, Greensboro, NC 27419. There were no comments received in 
    response to the notice of filing.
        The initial petition requested that 40 CFR 180.449 be amended by 
    establishing a tolerance for combined residues of the insecticide 
    avermectin B1 (a mixture of avermectins containing greater 
    than or equal to 80% avermectin B1a (5-O-demethyl avermectin 
    A1) and less than or equal to 20% avermectin B1b 
    (5-O-demethyl-25-de(1-methylpropyl)-25-(1-methylethyl) avermectin 
    A1)) and its delta-8,9-isomer, in or on grapes, raisins, and 
    other grape-derived food items at 0.02 ppm and chili peppers at 0.01 
    ppm. The petition was subsequently revised to express the tolerance as 
    simply peppers (combining the proposed chili peppers with the existing 
    0.01 ppm bell pepper tolerance) and raising the level to 0.02 ppm to 
    harmonize the tolerance with international residue limits. In addition, 
    the petition was also revised to express the proposed tolerance as 
    simply grapes at 0.02 ppm since residue data showed that separate, 
    higher tolerance levels were not needed for raisins and other grape-
    derived food items as expressed in the original petition.
        Section 408(b)(2)(A)(i) of the 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) 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) 
    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 and a complete description of 
    the risk assessment process, see the final rule on Bifenthrin Pesticide 
    Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).
    
    B. Conversion of Certain Tolerances from Time-limited to Permanent
    
        In the Federal Register of July 29, 1999 (64 FR 41112) (FRL-6095-
    6), EPA issued a notice pursuant to section 408 of the FFDCA, 21 U.S.C. 
    346a as amended by the FQPA (Public Law 104-170) announcing the filing 
    of a pesticide petition (PP) by Novartis Crop Protection, Inc., PO Box 
    18300, Greensboro, NC 27419 to convert certain time limited tolerances 
    due to expire September 1, 1999 to permanent tolerances and to add a 
    new tolerance for a feed commodity. There were no comments received in 
    response to the notice of filing.
        The petition referenced pesticide petitions PP 8F3592, 7F3500, 
    4E4419 and 5F4508. It requested that 40 CFR 180.449 be amended by 
    establishing permanent tolerances for combined residues of the 
    insecticide avermectin B1 (a mixture of avermectins 
    containing greater than or equal to 80% avermectin B1a (5-O-
    demethyl avermectin A1) and less than or equal to 20% 
    avermectin B1b (5-O-demethyl-25-de(1-methylpropyl)-25-(1-
    methylethyl) avermectin A1)) and its delta-8,9-isomer, in or 
    on the agricultural commodities cattle, fat at 0.015 ppm; cattle, meat 
    byproducts at 0.02 ppm; cattle, meat at 0.02 ppm; citrus, dried pulp at 
    0.10 ppm; citrus, oil at 0.10 ppm; citrus, whole fruit at 0.02 ppm; 
    cotton seed at 0.005 ppm; cotton gin by-products at 0.15 ppm; hops, 
    dried at 0.20 ppm; milk at 0.005 ppm; and potatoes at 0.005 ppm.
        With the exception of cotton gin by-products, these tolerances were 
    previously established as time-limited tolerances with an expiration 
    date of September 1, 1999 (see Federal Register of March 24, 1997 (62 
    FR 13833) (FRL-5597-7) to allow for resolution of the following three 
    issues:
        1. The petitioner had to submit field residue trial data for cotton 
    gin byproducts and the EPA had to reevaluate dietary risk with respect 
    to secondary residues in meat and milk. These data were submitted; the 
    review is discussed later in this rule. As a result of this review, the 
    July 29, 1999 notice proposed the new tolerance for cotton gin 
    byproducts at 0.15 ppm.
        2. The EPA needed to fully review the Monte Carlo analysis for 
    acute dietary risk submitted by the petitioner (especially the 
    anticipated residues and percent of crop treated data used). This 
    review was conducted as part of the tolerance assessment for grapes and 
    peppers.
    
    [[Page 48550]]
    
        3. The EPA needed to fully review the indoor residential risk 
    assessment submitted by the petitioner. This review was conducted as 
    part of the tolerance assessment for grapes and peppers. Since all 
    three issues have been satisfactorily addressed, the petitioner is 
    seeking to make the tolerances permanent.
    
    C. Clarification: Certain Feed Tolerances Previously Established
    
        In the Federal Register of April 10, 1996 (61 FR 15900) (FRL-5361-
    9), EPA issued a final rule pursuant to section 409(e) of the FFDCA, 21 
    U.S.C. 348(b) announcing permanent tolerances under 40 CFR 186.300 for 
    combined residues of the insecticide avermectin B1 (a 
    mixture of avermectins containing greater than or equal to 80% 
    avermectin B1a (5-O-demethyl avermectin A1) and 
    less than or equal to 20% avermectin B1b (5-O-demethyl-25-
    de(1-methylpropyl)-25-(1-methylethyl) avermectin A1)) and 
    its delta-8,9-isomer, in or on the processed feed commodities apples, 
    wet pomace at 0.10 ppm and almonds, hulls at 0.10 ppm. This regulation 
    also established permanent tolerances under 40 CFR 180.449 on the raw 
    agricultural commodities almonds at 0.005 ppm; apples at 0.020 ppm; and 
    walnuts at 0.005 ppm.
        Although that final rule listed tolerances for both raw 
    agricultural commodities and feed commodities, the 1996 edition of 40 
    CFR parts 150-189 (revised as of July 1, 1998), and subsequent 
    editions, listed only the tolerances for the raw agricultural 
    commodities and did not list the feed commodities established by this 
    regulation. With this current regulation the Agency is clarifying that 
    tolerances have been legally in effect since April 10, 1996 for the 
    processed feed commodities apples, wet pomace at 0.10 ppm and almonds, 
    hulls at 0.10 ppm. Due to amendments to the FFDCA by the FQPA, all 
    (i.e. raw, processed, and feed commodity) tolerances for avermectin 
    B1 and its delta-8,9-isomer are now listed in the same 
    section of 40 CFR (180.449).
    
    III. Aggregate Risk Assessment and Determination of Safety
    
        Consistent with 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 
    avermectin B1 and its delta-8,9-isomer and to make a 
    determination on aggregate exposure, consistent with section 408(b)(2), 
    for a tolerance for combined residues of the insecticide avermectin 
    B1 (a mixture of avermectins containing greater than or 
    equal to 80% avermectin B1a (5-O-demethyl avermectin 
    A1) and less than or equal to 20% avermectin B1b 
    (5-O-demethyl-25-de(1-methylpropyl)-25-(1-methylethyl) avermectin 
    A1)) and its delta-8,9-isomer on grapes at 0.02 ppm and 
    peppers at 0.02 ppm. EPA's assessment of the dietary exposures and 
    risks associated with establishing the tolerance 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. The nature of the toxic effects caused by avermectin 
    B1 and its delta-8,9-isomer are discussed in this unit.
        1. Acute toxicity/skin sensitization. The following summarizes the 
    acute toxicity of technical grade avermectin B1: the acute 
    oral LD50 is 13.6 milligrams/kilogram (mg/kg) (toxicity 
    category I); the acute dermal LD50 is 2,000 mg/kg (toxicity 
    category III); acute inhalation requirements were waived; primary eye 
    irritation results show the chemical to be very irritating exhibiting 
    corneal opacity, conjunctivitis, and iritis (toxicity category II); 
    primary skin irritation results show slight irritation (toxicity 
    category III); dermal sensitization results are negative.
        2. Subchronic toxicity. In a 14-Week Oral Toxicity Study in Rats, 
    groups of 15 male and 15 female Charles River CD rats were gavaged with 
    0, 0.1, 0.2, or 0.4 mg/kg/day of C-076 (avermectin B1). The 
    rats had previously been exposed in utero to avermectin B1 
    at doses of 0, 0.01, 0.2, or 0.4 mg/kg/day. No toxic signs or deaths 
    were noted in any of the treatment groups. Body weight gain was 
    increased in the rats dosed at 0.4 mg/kg/day. There were no treatment-
    related ophthalmologic changes, clinical pathology anomalies, gross or 
    histopathologic lesions, or changes in organ weights. The No Observable 
    Adverse Effect Level (NOAEL) is > 0.4 mg/kg/day, the highest dose 
    tested.
        An 18-Week Oral Toxicity Study in Dogs resulted in a NOAEL of 0.25 
    mg/kg/day with the Lowest Observed Adverse Effect Level (LOAEL) being 
    0.5 mg/kg/day based on body tremors, one death, liver pathology, and 
    decreased body weight.
        3. Chronic toxicity/ongogenicity/carcinogenicity. In a Combined 
    Chronic Toxicity/Oncogenicity Study in Rats, the oncogenic potential 
    was negative up to 2.0 mg/kg/day, the highest dose tested (HDT). The 
    high dose was increased to 2.5 mg/kg/day between weeks 10 and 13. The 
    high-dose is considered the Maximum Tolerated Dose (MTD). The systemic 
    NOAEL is 1.5 mg/kg/day (mid-dose). The LOAEL is 2.0 mg/kg/day based on 
    tremors in both sexes. A mid-dose female that had tremors was found to 
    have received a dose of about 2.5 mg/kg/day (based on actual food 
    consumption and body weight data). No pathological lesions could be 
    found to explain the tremors.
        In a Carcinogenicity Study in Mice, oncogenic potential was 
    negative up to 8 mg/kg/day, the HDT. The high-dose (8 mg/kg/day) is 
    considered the MTD. The systemic NOAEL is 4 mg/kg/day. The LOAEL is 8 
    mg/kg/day based on increased incidence of dermatitis in males, an 
    increased incidence of extra-medullary splenic hematopoiesis in males, 
    increased mortality in males, and tremors and body weight decrease in 
    females.
        In a 53-Week Oral Toxicity Study in Dogs, the NOAEL is 0.25 mg/kg/
    day, and the LOAEL is 0.50 mg/kg/day based on a high incidence of 
    mydriasis (dilatation of the pupil of the eye) in males and females.
        4. Developmental and reproductive toxicity. In a Developmental 
    Toxicity Study in Rats, groups of 25 female CRCD rats were mated, then 
    dosed by gavage with technical MK-0936 (avermectin B1) at 0 
    (vehicle control), 0.4, 0.8, or 1.6 mg/kg/day on gestation days 6 
    through 19. The lack of any maternal or developmental toxicity 
    demonstrates that the doses selected for this study were too low to 
    establish a LOAEL. The maternal and developmental NOAELs are > 1.6 mg/
    kg/day (the HDT).
        In a Developmental Toxicity Study in Rabbits, the maternal NOAEL is 
    1.0 mg/kg/day, and the maternal LOAEL is 2.0 mg/kg/day based on 
    decreased body weights, food consumption, and water consumption. The 
    developmental NOAEL is 1.0 mg/kg/day, and the Developmental LOAEL is 
    2.0 mg/kg/day based on cleft palate, clubbed foot, and delayed 
    ossification of sternebrae, metacarpals, and phalanges.
        In a 2-generation Reproduction Study in Rats, the systemic and 
    reproductive NOAELs are  0.40 mg/kg/day. The developmental 
    NOAEL is 0.12 mg/kg/day, and the developmental LOAEL is 0.40 mg/kg/day 
    based on decreased pup body weight and viability during lactation, and 
    increased incidence of retinal rosettes in F2b weanlings.
        In a Special Developmental Toxicity Study in CF-1 Mice, a genotypic 
    susceptibility to cleft palate was seen
    
    [[Page 48551]]
    
    following in utero exposure of avermectin B1 delta 8-9 
    isomer (an isomeric photodegradation product found in plants). P-
    glycoproteins are large proteins (150-180 kDa) found in the cell 
    membranes of animals ranging from sponges to humans. Groups of 12 P-
    glycoprotein molecules span the lipid bilayer to form pores that 
    protect the cell by secreting toxic chemicals (such as the avermectins) 
    at the expense of ATP.
        The CF-1 mouse strain is unique in that it contains a spontaneous 
    mutation in the P-glycoprotein gene resulting in heterogeneity in the 
    expression of the protein, a component of the blood-brain and blood-
    placental barrier. Mice with a  or -/- genotype have 
    decreased expression of this protein. A decrease in expression of the 
    P-glycoprotein in both the gastrointestinal tract and brain increased 
    the sensitivity of CF-1 mice to avermectin toxicity by increasing its 
    absorption. Because the protein is also a component of the placental-
    blood barrier, it was hypothesized that a deficiency of this protein in 
    the placenta may increase the sensitivity of the fetus to the 
    avermectins. In this exploratory developmental toxicity study, the role 
    of fetal P-glycoprotein genotype in the development of cleft palate in 
    CF-1 mice was investigated.
        Heterozygous () male and female mice for P-glycoprotein 
    expression were mated. The dams were dosed by gavage with 1.5 mg/kg/day 
    of the test article on gestation days 6-15, inclusive. The pups had the 
    typical 1:2:1 Mendelian expression of P-glycoprotein deficiency (+/+, 
    , and -/-, respectively).
        There was a clear correlation between fetal P-glycoprotein genotype 
    and cleft palate incidence. Cleft palate was observed in 97% of fetuses 
    with the -/- genotype, 41% of fetuses with the  genotype, 
    and none of the fetuses with the +/+ genotype. It was postulated that 
    placental P-glycoprotein limited the potential of the test article to 
    induce cleft palate in the fetuses, presumably by regulating the amount 
    of test material allowed to cross the placental barrier into the 
    developing fetus.
        The literature contains no mention of P-glycoprotein deficiency in 
    humans, and several scientists who are researching P-glycoprotein 
    confirmed this. Since there is no known human correlate for P-
    glycoprotein deficiency, the CF-1 mouse should not be used for 
    assessing the risk of human exposure to avermectins. Although several 
    developmental toxicity studies were performed using CF-1 mice, they are 
    inappropriate for regulatory purposes.
        5. Mutagenicity. The available studies clearly indicate that 
    avermectin B1, delta-8,9-isomer (a plant metabolite), and 
    the polar photolysis degradates are not mutagenic in microbial systems. 
    While avermectin B1 has the potential to damage DNA, the 
    lack of an in vitro mutagenic or clastogenic effect correlates well 
    with the lack of an oncogenic effect in rat or mouse long-term feeding 
    studies and also with the absence of significant reproductive or 
    developmental toxicity attributable to a mutagenic mode of action 
    (i.e., decreased total implants or increased resorptions).
        6.  Metabolism. In a metabolism study in rats, two metabolites were 
    identified, 2,4-OH-ME-B1a, and 3''desmethyl avermectin 
    B1a (3''DM-B1a). No bioaccumulation was seen in 
    rat tissues.
        7. Neurotoxicity. There are no neurotoxicity or developmental 
    neurotoxicity studies of avermectin B1. However, 
    neurotoxicity was observed in other oral toxicity studies. A chronic 
    study in dogs resulted in mydriasis at 0.50 mg/kg/day. A chronic/
    oncogenicity study in rats resulted in tremors in both sexes at the 
    LOAEL of 2.0 mg/kg/day. A chronic/carcinogenicity study in mice 
    resulted in tremors in females at the LOAEL of 8 mg/kg/day. In an 18-
    week study in dogs signs, seen at 0.50 mg/kg/day included mydriasis, 
    whole body tremors, ataxia (lack of coordination), muscular tremors, 
    and ptyalism (excessive flow of saliva). In a 10-day developmental 
    toxicity study in CF-1 mice, hunched back and marked tremors were 
    observed after 6-7 days dosing at 0.3 mg/kg/day in the diet. In a 
    reproduction study in rats, spastic movements of the limbs and muscular 
    tremors of the entire body were seen in lactating pups, but not in the 
    dams, at 0.4 mg/kg/day. In a reproduction study in rats, whole body 
    tremors, ataxia, ptyalism, and ocular and/or nasal discharges were seen 
    in dams dosed at 2.0 mg/kg/day (no mention of neurotoxicity in the 
    pups). In two developmental toxicity studies in CF-1 mice, death was 
    preceded by tremors, then coma.
    
    B. Toxicological Endpoints
    
        1. Acute toxicity. An acute dietary Reference Dose (RfD) of 0.0025 
    mg/kg was based on data from a 1-year dog study. The NOAEL is 0.25 mg/
    kg/day, and the LOAEL is 0.50 mg/kg/day based on mydriasis which was 
    observed after 1 week of dosing. An uncertainty factor of 100 was used 
    to account for interspecies extrapolation (10x) and intraspecies 
    variability (10x).
        2. Short- and intermediate-term toxicity. Short- and intermediate-
    term dermal and inhalation NOAELs are derived by route-to-route 
    extrapolation of the oral NOAEL of 0.25 mg/kg/day based on mydriasis 
    after 1 week of dosing in a 1-year dog study. Dermal absorption is 
    considered to be 1% based on a monkey study that found dermal 
    absorption to be less than 1% (rounded up to 1% for analysis purposes). 
    Oral and inhalation absorption are both assumed to be 100%.
        3. Chronic toxicity. EPA has established the RfD for avermectin 
    B1 and its delta-8,9-isomer at 0.0012 mg/kg/day. This 
    Reference Dose (RfD) is based on a 2-generation reproduction study in 
    rats. The developmental NOAEL is 0.12 mg/kg/day, and the developmental 
    LOAEL is 0.40 mg/kg/day based on decreased pup body weight and 
    viability during lactation, and increased incidence of retinal rosettes 
    in F2b weanlings. An uncertainty factor of 100 was used to account for 
    interspecies extrapolation (10x) and intraspecies variability(10x).
        The long-term dermal NOAEL is a route-to-route extrapolation of the 
    oral NOAEL of 0.12 mg/kg/day based on decreased pup body weight and 
    viability during lactation, and increased incidence of retinal rosettes 
    in F2b weanlings in a 2-generation reproduction study in rats. Dermal 
    absorption is considered to be 1% based on a monkey study that found 
    dermal absorption to be less than 1% (rounded up to 1% for analysis 
    purposes).
        The long-term inhalation NOAEL is a route-to-route extrapolation 
    from the oral NOAEL of 0.12 mg/kg/day based on decreased pup body 
    weight and viability during lactation, and increased incidence of 
    retinal rosettes in F2b weanlings in a 2-generation reproduction study 
    in rats. Oral and inhalation absorption are both assumed to be 100%.
        4. Carcinogenicity. The Agency has classified avermectin 
    B1 as a Cancer Group E chemical based on the absence of 
    significant tumor increases in two adequate rodent carcinogenicity 
    studies.
    
    C. Exposures and Risks
    
        1. From food and feed uses. Tolerances have been established (40 
    CFR 180.449) for the combined residues of the insecticide avermectin 
    B1 (a mixture of avermectins containing greater than or 
    equal to 80% avermectin B1a (5-O-demethyl avermectin 
    A1) and less than or equal to 20% avermectin B1b 
    (5-O-demethyl-25-de(1-methylpropyl)-25-(1-methylethyl) avermectin 
    A1)) and its delta-8,9-isomer, in or on a variety of raw 
    agricultural commodities. Permanent tolerances include almonds (0.005 
    ppm); almonds, hulls (0.10 ppm); apples (0.020 ppm); apples, wet pomace 
    (0.10 ppm); celery
    
    [[Page 48552]]
    
    (0.05 ppm); cucurbits (0.005 ppm); head lettuce (0.05 ppm); pears (0.02 
    ppm) bell peppers (0.01 ppm) strawberry (0.02 ppm); fresh tomatoes 
    (0.01 ppm); walnuts (0.005 ppm). The following time limited tolerances 
    are due to expire September 1, 1999: cattle, fat (0.015 ppm); cattle, 
    meat (0.02 ppm); cattle, meat by products (0.02 ppm); citrus, dried 
    pulp (0.10 ppm); citrus, oil (0.10 ppm); citrus, whole fruit (0.02 ppm) 
    cotton seed (0.005 ppm); dried hops (0.2 ppm); milk (0.005 ppm); 
    potatoes (0.005 ppm). The following Section 18 time limited tolerances 
    will expire January 31, 2,000: basil (0.05 ppm); celeriac (0.05 ppm) 
    spinach (0.05 ppm). Finally, a section 18 time limited tolerance for 
    avocado (0.02 ppm) will expire September 20, 2,000. All of these 
    tolerances (i.e. both permanent and time-limited) were included in the 
    dietary risk analysis. Risk assessments were conducted by EPA to assess 
    dietary exposures from avermectin B1 and its delta-8,9-
    isomer as follows:
        Section 408(b)(2)(E) authorizes EPA to use available data and 
    information on the anticipated residue levels of pesticide residues in 
    food and the actual levels of pesticide chemicals that have been 
    measured in food. If EPA relies on such information, EPA must require 
    that data be provided 5 years after the tolerance is established, 
    modified, or left in effect, demonstrating that the levels in food are 
    not above the levels anticipated. Following the initial data 
    submission, EPA is authorized to require similar data on a time frame 
    it deems appropriate. As required by section 408(b)(2)(E), EPA will 
    issue a data call-in for information relating to anticipated residues 
    to be submitted no later than 5 years from the date of issuance of this 
    tolerance.
        Section 408(b)(2)(F) states that the Agency may use data on the 
    actual percent of crop treated (PCT) for assessing chronic dietary risk 
    only if the Agency can make the following three findings: (1) That the 
    data used are reliable and provide a valid basis to show what 
    percentage of the food derived from such crop is likely to contain such 
    pesticide residue; (2) that the exposure estimate does not 
    underestimate exposure for any significant subpopulation group; and (3) 
    if data are available on pesticide use and food consumption in a 
    particular area, the exposure estimate does not understate exposure for 
    the population in such area. In addition, the Agency must provide for 
    periodic evaluation of any estimates used. To provide for the periodic 
    evaluation of the estimate of percent of crop treated as required by 
    the section 408(b)(2)(F), EPA may require registrants to submit data on 
    PCT.
        The Agency used the following information to conduct a dietary 
    exposure analysis. The maximum PCT is used for acute dietary exposure 
    estimates and represents the highest levels to which an individual 
    could be exposed. It is unlikely to underestimate an individual's acute 
    dietary exposure. The weighted average percent crop treated is used for 
    chronic dietary exposure and reasonably represents a person's dietary 
    exposure over a lifetime. It is unlikely to underestimate exposure to 
    an individual because of the fact that pesticide use patterns (both 
    regionally and nationally) tend to change continuously over time, so 
    that an individual is unlikely to be exposed to more than the average 
    percent crop treated over a lifetime. For each crop in the dietary 
    (food only) model the following percent crop treated values were used 
    for the acute and chronic analyses (respectively): almond 100%, 100%; 
    apple 6.1%, 1.9%; avocado 100%, 100%; basil 100%, 100%; cantaloupe 5%, 
    1.3%; celeriac 100%, 100%; celery 60%, 49%; citrus, other 43%, 32%; 
    cotton 4.8%, 3.2%; cucumber 100%, 31%; grapefruit, juice and peel 
    60.9%, 46%; grapefruit, peeled fruit 43%, 46%; grape 14%, 14%; hops 
    100%, 84%; lemon, juice and peel 34.4%, 17%; lemon, peeled fruit 43%, 
    17%; head lettuce 28%, 22%; lime, juice and peel 63.2%, 32%; lime, 
    peeled fruit 43%, 32%; melons 5%, 1.3%; orange, juice and peel 36.3%, 
    28%; orange, peeled fruit 43%, 28%; pear 75%, 56%; peppers 15%, 6.3%; 
    potato 5%, 0.3%; spinach 18%, 8.9%; squash 100%, 31%; strawberry 47%, 
    42%; tangelo 43%, 57%; tangerine, juice 74.3%, 53%; tangerine, fresh 
    43%, 53%; tomato 8%, 3.7%; walnut 100%, 100%; watermelon 5%, 1.3%. For 
    fresh, peeled citrus a weighted average (43%) was calculated pooling 
    all types of citrus; this value was used in the analysis of chronic 
    dietary exposure from citrus.
        The Agency believes that the three conditions, discussed in section 
    408 (b)(2)(F) in this unit concerning the Agency's responsibilities in 
    assessing chronic dietary risk findings, have been met. With respect to 
    condition 1, EPA finds that the PCT information is reliable and has a 
    valid basis. The Agency has utilized statistical data from a number of 
    public and proprietary sources including USDA/National Agricultural 
    Statistics Service, Doane, Maritz, Kline, and National Center for Food 
    and Agricultural Policy. However, since the risk assessment includes 
    forecast estimates of usage of avermectin B1 on the new 
    crops being added, the petitioner must seek permission from the Agency 
    to expand usage beyond these estimates (specifically, 14% crop treated 
    for grapes, 15% crop treated for peppers). Before the petitioner can 
    increase production of product for treatment of greater than 115,500 
    acres for grapes (14% of 825,000 total U.S. acres grown) or 17,850 
    acres for peppers (15% of 119,000 total U.S. acres grown), permission 
    from the Agency must be obtained. With respect to conditions 2 and 3, 
    the regional consumption information and consumption information for 
    significant subpopulations is taken into account through EPA's 
    computer-based model for evaluating the exposure of significant 
    subpopulations including several regional groups. Use of this 
    consumption information in EPA's risk assessment process ensures that 
    EPA's exposure estimate does not understate exposure for any 
    significant subpopulation group and allows the Agency to be reasonably 
    certain that no regional population is exposed to residue levels higher 
    than those estimated by the Agency. Other than the data available 
    through national food consumption surveys, EPA does not have available 
    information on the consumption of food bearing avermectin B1 
    and its delta-8,9-isomer in a particular area.
        i. Acute exposure and risk. Acute dietary 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. The registrant has submitted an acute 
    dietary exposure assessment using probabilistic ``Monte Carlo'' 
    modeling incorporating anticipated residue and percent of crop treated 
    refinements to calculate the Anticipated Residue Contribution (ARC). 
    EPA has examined the assumptions made in conducting the analysis for 
    the following crops: celery, strawberry, citrus, tomato, and pear, 
    apple, grape, and pepper. EPA found the analysis adequate with the 
    exception of the acute RfD; the analysis was not conducted with the 
    current acute population adjusted dose (PAD) of 0.00025 mg/kg/day. 
    Residue Data Files (RDF) and percent crop treated were used on all but 
    a few low consumption food items. Reduction factors for fractionation 
    and processing were utilized for citrus and pome fruit. Monitoring data 
    were not used for mixed/blended commodities.
        EPA was able to further refine the acute dietary estimate from food 
    by using updated PCT data, resetting the processing factor for dried 
    potatoes to 1 which reflects the non-concentration of
    
    [[Page 48553]]
    
    avermectin B1 in potato processed commodities, correcting 
    the residue files above to use one half the level of detection or one 
    half the level of quantification, where appropriate, and using the 
    average field trial residue level and previously established processing 
    factors for blended commodities. In addition, the analysis included 
    residues in pear juice for which no data has been previously required. 
    Since all other juices show reductions in avermectin B1 
    residues from the raw agricultural commodity, EPA will use the 
    reduction factor for apples in the analysis. Some of the resulting 
    high-end exposure estimates are listed below.
        The resulting calculations are presented below as a percent of the 
    acute population adjusted dose (%PAD). The PAD is the reference dose 
    (acute or chronic) adjusted for (divided by) the FQPA safety factor. 
    EPA is generally concerned with acute exposures that exceed 100% of the 
    acute RfD/PAD. The risk estimate should be viewed as highly refined. 
    Additional refinement of the almond, basil, cotton seed, hops and 
    walnut residue estimates using RDF's and PCT would be unlikely to 
    reduce risk estimates significantly. In making a safety determination 
    for this tolerance, EPA is taking into account this refined acute 
    exposure assessment.
    
    Table 1.-- Acute Dietary (Food Only) Risk for Selected Population Groups
    ------------------------------------------------------------------------
                                                            ARC (mg/    PAD
                           Subgroup                            kg)      (%)
    ------------------------------------------------------------------------
    U.S. Population.......................................  0.000088       4
    All infants (< 1="" yr.).................................="" 0.000111="" 44="" nursing="" infants="">< 1="" yr.).............................="" 0.000112="" 45="" non-nursing="" infants="">< 1="" yr.).........................="" 0.000117="" 47="" children="" (1-6="" yrs.)...................................="" 0.000176="" 70="" children="" (7-12="" yrs.)..................................="" 0.00008="" 34="" 5="" females="" (13+="" yrs.="" pregnant,="" non-nursing)..............="" 0.000054="" 22="" females="" (13+="" yrs.="" nursing)............................="" 0.000093="" 37="" females="" (13-19="" yrs.="" non-pregnant,="" non-nursing)........="" 0.000061="" 24="" females="" (13-50="" yrs.)..................................="" 0.000070="" 28="" males="" (13-19="" yrs.)....................................="" 0.000051="" 2="" ------------------------------------------------------------------------="" ii.="" chronic="" exposure="" and="" risk.="" in="" conducting="" this="" chronic="" dietary="" (food="" only)="" risk="" assessment,="" epa="" used="" anticipated="" residues="" and="" percent="" crop-treated="" data="" for="" many="" crops.="" this="" chronic="" dietary="" (food="" only)="" exposure="" should="" be="" viewed="" as="" a="" highly="" refined="" risk="" estimate;="" further="" refinement="" using="" additional="" percent="" crop-treated="" values="" would="" not="" result="" in="" a="" significantly="" lower="" dietary="" exposure="" estimate.="" thus,="" in="" making="" a="" safety="" determination="" for="" this="" tolerance,="" epa="" is="" taking="" into="" account="" this="" refined="" chronic="" exposure="" assessment.="" epa="" is="" generally="" concerned="" with="" exposures="" that="" exceed="" 100%="" of="" the="" chronic="" rfd/pad.="" the="" existing="" avermectin="">1 tolerances result in an ARC that is 
    equivalent to the following percentages of the RfD or PAD depending on 
    the subpopulation:
    
       Table 2.--Chronic Dietary (Food Only) Risk for Selected Population
                                     Groups
    ------------------------------------------------------------------------
                                                             ARCFOOD    PAD
                           Subgroup                          (mg/kg)    (%)
    ------------------------------------------------------------------------
    U.S. Population.......................................  0.000008     < 1="" u.s.="" population="" -="" autumn="" season.......................="" 0.000008="" 7="" northeast="" region......................................="" 0.000008="" 7="" western="" region........................................="" 0.000009="" 7="" pacific="" region........................................="" 0.000009="" 7="" non-hispanic="" other....................................="" 0.000008="" 7="" all="" infants="">< 1="" yr.).................................="" 0.000016="" 14="" nursing="" infants="">< 1="" yr.).............................="" 0.000009="" 7="" non-nursing="" infants="">< 1="" yr.).........................="" 0.000020="" 17="" children="" (1-6="" yrs.)...................................="" 0.000016="" 13="" children="" (7-12="" yrs.)..................................="" 0.000010="" 8="" females="" (13+="" yrs.="" nursing.............................="" 0.000008="" 6="" males="" (20+="" years).....................................="" 0.000007=""><1 ------------------------------------------------------------------------="" the="" subgroups="" listed="" above="" are:="" (1)="" the="" u.s.="" population="" (48="" states);="" (2)="" those="" for="" infants,="" children,="" females="" 13+,="" nursing;="" (3)="" the="" other="" subgroups="" for="" which="" the="" percentage="" of="" the="" rfd/pad="" occupied="" is="" greater="" than="" that="" occupied="" by="" the="" subgroup="" u.s.="" population;="" and="" (4)="" other="" subgroups="" of="" regulatory="" interest.="" 2.="" from="" drinking="" water.="" avermectin="">1 is moderately 
    persistent and non-mobile. It is not expected to reach surface or 
    ground water in significant quantities. It is stable to hydrolysis at 
    pH 5, 7, and 9. It is also moderately persistent in aerobic soil 
    (topsoil) with half-lives of 37-131 days. The major pathways of 
    avermectin B1 dissipation are binding to soil and sediment, 
    degradation in aerobic soil, and photolysis in water. In shallow, well-
    mixed surface water with no suspended sediments, avermectin 
    B1 degraded rapidly with a photodegradation half-life of 3 
    days. However, in most surface waters, suspended sediments and lack of 
    mixing would decrease the rate of photodegradation significantly. In 
    water, avermectin B1 residues would be tightly bound to 
    sediment, reducing aqueous concentrations. There are no Maximum 
    Contaminant Levels (MCL) or Health Advisories (HA) established for 
    avermectin B1 residues in drinking water.
        To calculate exposure and risk from avermectin B1 in 
    drinking water, the EPA analysis first used screening models to 
    calculate Estimated Environmental Concentrations (EECs) for groundwater 
    (screening concentration in ground water (SCI-GROW2)) and surface water 
    (generic expected environmental concentration (GENEEC)). A refined 
    model (Pesticide Root Zone Model-EXAMS (PRZM-EXAMS)) was then run on 
    surface water (refined models do not exist for ground water but given 
    the screening results it is unlikely that the EECs for ground water 
    would change significantly). The resulting EECs were then compared to 
    the Drinking Water Level of Concern (DWLOC) for various population 
    groups to determine acute and chronic risk.
        The screening model SCI-GROW2 was used to calculate EECs for 
    avermectin B1 in ground water from use in grapes, peppers, 
    and strawberries. Strawberries were analyzed since they represent the 
    highest avermectin B1 use rate for any crop. These EECs were 
    0.0015, 0.0015, and .002 g/L for grapes, peppers, and 
    strawberries, respectively.
        PRZM-EXAMS was used to perform a refined assessment of EECs for 
    avermectin B1 in surface drinking water. Use sites modeled 
    were grapes grown with grassed middles in New York and strawberries 
    grown on black plastic mulch in Florida. Peppers were not modeled 
    because the application rate is lower than that for strawberries. Crop 
    specific consecutive PRZM-EXAMS simulations were conducted to evaluate 
    the cumulative probability distribution for peak, 4-day, 21-day, 60-
    day, and 90-day EECs. PRZM-EXAMS EECs for avermectin B1 were 
    0.18 and 0.88 g/L for peak values and 0.16 and 0.57 
    g/L for 90-day for grape and strawberries, respectively.
        EPA decided to rely on the strawberry model to assess aggregate 
    risk since strawberries were considered a higher exposure scenario 
    (four applications per season allowed for strawberries vs. three 
    applications for peppers or two applications for grapes). However, EPA 
    noted that the certainty of the concentrations estimated for 
    strawberries is low, due to uncertainty on the amount of runoff from 
    plant beds covered in plastic mulch and uncertainty on the amount of 
    degradation of avermectin B1 on black plastic compared to 
    soil. In order to refine the model in the future, the Agency will 
    require the registrant, as a condition of product registration, to 
    conduct additional tests on the effects of plastic mulch on surface 
    water pesticide concentrations.
    
    [[Page 48554]]
    
        A Drinking Water Level of Comparison (DWLOC) is a theoretical upper 
    limit of a pesticide's concentration in drinking water in light of 
    total aggregate exposure to that pesticide in food and through 
    residential uses. A DWLOC will vary depending on the toxic endpoint, 
    consumption, and body weight. Different populations will have different 
    DWLOCs. EPA uses DWLOCs internally in the risk assessment process as a 
    surrogate measure of potential exposure associated with pesticide 
    exposure through drinking water. In the absence of monitoring data for 
    pesticides, the DWLOC is used as a point of comparison against 
    conservative model estimates of potential pesticide concentration in 
    water. DWLOC values are not regulatory standards for drinking water.
         Acute and chronic exposure and risk. No monitoring data of ground 
    water and surface water are available for avermectin B1. The 
    SCI-GROW2 modeling data for the grape and chili pepper uses resulted in 
    maximum concentrations in ground water of 0.0015 g/L for both 
    acute and chronic exposure. Refinements using PRZM-EXAMS indicate a 
    peak EEC in surface water at 0.88 g/L and a 90-day EEC at 0.57 
    g/L. The modeling data were compared to the results of the 
    following equations used to calculate acute and chronic DWLOC for 
    avermectin B1 in ground and surface water. Additionally, as 
    a result of the retention of the FQPA Safety Factor, EPA considered the 
    PAD for females 13+, infants, and children to be 0.00025 and 0.00012 
    mg/kg/day for acute and chronic exposure, respectively. For all other 
    populations (e.g. U.S. population, Hispanics, adult males), exposures 
    will be compared to the acute and chronic PADs, 0.0025 and 0.0012 mg/
    kg/day, respectively.
        DWLOC's are calculated as follows: Acute = (acuteRfD/10) - (acute 
    food (mg/kg/day))  x  (bodyweight) / consumption (L)  x  
    10-3 mg/g. Chronic = (RfD/10) - (chronic food (mg/
    kg/day))  x  (bodyweight)/consumption (L)  x  10-3 mg/
    g. The 2 liters (L) of drinking water consumed/day by adults 
    and the 1 L per day consumed by children are default assumptions used 
    by the EPA. The Agency's default body weights for the U.S. population 
    and males is 70 kg and for females, 60 kg. EPA's default body weight 
    for children is 10 kg. There are no chronic residential exposures to 
    avermectin B1.
        The results indicate that the exposure to avermectin B1 
    in drinking water derived from ground water using SCI-GROW modeling 
    data are below the calculated DWLOC for all population subgroups of 
    concern from use of avermectin B1 in grapes, peppers and 
    strawberries. Exposure to avermectin B1 in drinking water 
    derived from surface water using the refined estimates from PRZM-EXAMS 
    and using the results for the crop with the highest use rate 
    (strawberries) the modeled exposure data are below the calculated DWLOC 
    for all population subgroups of concern except for the acute exposure 
    for children 1-6 yrs where the modeled exposure concentration slightly 
    exceeds the DWLOC (0.88 vs. 0.74 g/L).
        Despite this slight exceedance, EPA believes that acute exposure to 
    avermectin from drinking water will not pose an unacceptable risk to 
    human health. Neither surface nor ground water models used by EPA were 
    designed specifically for estimating concentrations in drinking water. 
    There are significant uncertainties in both the toxicology used to 
    derive the DWLOC and the exposure estimate from the PRZM-EXAMS model. 
    EPA has compensated for these uncertainties by using reasonable high-
    end assumptions. Given this approach, the Agency does not attach great 
    significance to such a small difference. However, EPA may do additional 
    analyses and, as a condition of product registration, the Agency will 
    require the registrant to submit (1) data on the effects of plastic 
    mulch on surface water pesticide concentrations and (2) data 
    characterizing the effectiveness of various types of drinking water 
    treatment on removing avermectin. These data are expected to confirm 
    that the actual concentration of avermectin in drinking water is less 
    than the level of concern for all sub-populations.
        3. From non-dietary exposure. Avermectin B1 and its 
    delta-8,9-isomer is currently registered for use on the following 
    residential non-food sites: residential lawns for fire ant control, and 
    residential indoor crack & crevice for cockroaches. Registered 
    residential uses may result in short-term to intermediate exposures. 
    However, based on current use patterns, chronic exposure (6 or more 
    months of continuous exposure) to avermectin B1 is not 
    expected.
        i. Short and intermediate exposure and risk--residential lawn 
    applications. For exposure of residential applicators, three scenarios 
    used were: (a) granular bait dispersed by hand, (b) belly grinder-
    granular open pour-mixer/loader/applicator (MLAP) and (c) push type 
    granular MLAP. Short- and Intermediate-term total MOEs (dermal + 
    inhalation) are greater than 1,000 and therefore do not exceed EPA's 
    level of concern.
        For postapplication exposure from treated lawns, EPA default 
    assumptions such as dermal transfer coefficient (Tc), exposure time 
    (ET), hand surface area (SA), ingestion frequency (FQ), residue 
    dissipation, and ingestion rates were used. These defaults were used to 
    estimate postapplication exposure to children and adults from treated 
    lawns. The application rate (AR) used for this assessment is based on 
    the label for Affirm Fire Ant Insecticide (0.011% avermectin 
    B1). The label recommends a broadcast application rate on 
    lawns of 1 lb of product/acre (1.1E-4 lb ai/acre). This is maximum rate 
    for all registered lawn uses. A margin of exposure (MOE) of 1,000 or 
    greater is required for the most sensitive subgroups. All lawn 
    postapplication MOEs exceeded this value and are therefore not of 
    concern. The dermal short- and intermediate-term MOEs for adults and 
    children are 83,000 and 86,000, respectively. The oral hand-to-mouth 
    short- and intermediate-term MOEs for children are 14,000 and 6,500, 
    respectively. The oral incidental ingestion short- and intermediate-
    term MOEs for children are 610,000 and 290,000, respectively.
        ii. Short and intermediate exposure and risk--residential indoor 
    crack and crevice uses. For residential applicators, exposure and risk 
    estimates for homeowners applying crack and crevice baits were 
    estimated using the EPA DRAFT Standard Operating Procedure (SOP) for 
    Residential Exposure Assessments (12/18/97).
        The amount of active ingredient (ai) handled was based on the 
    assumption that one 30 gram package of Whitmire Avert Prescription Bait 
    Prescription Treatment 310 (0.05% ai) would be applied in a day. The 
    unit exposure from the EPA default wettable powder, open mixing and 
    loading scenarios was used as a surrogate for estimating dermal and 
    inhalation exposure to residential applicators. The short- and 
    intermediate-term MOEs for dermal and inhalation exposure are each 12 
    million, which does not exceed EPA's level of concern.
        For estimating postapplication exposure and risk from indoor 
    treatment, two postapplication exposure studies were conducted with 
    crack and crevice products containing avermectin B1: (1) 
    Evaluation of Avert Prescription Treatment 310 Residual Study in Air, 
    Food and on Surfaces, dated November 8, 1990 and (2) Evaluation of 
    Indoor Exposure to a Crack and Crevice Application of Whitmire Avert 
    Crack and Crevice Prescription Treatment 310 and Prescription TC 93A 
    Bait, dated October 27, 1995. The 1990 study reported measured 
    avermectin B1
    
    [[Page 48555]]
    
    concentrations in wipe and air samples up to 7 days following the 
    application. The 1995 study reported non-detect values for all air and 
    surface residue (cotton cloth dosimeters) samples taken.
        The EPA noted that neither study met 100% of the Pesticide 
    Assessment Guideline criteria. Among other shortcomings, the 1990 study 
    did not report the amount of avermectin B1 applied. However, 
    subsequent documentation provided by the study director stated that the 
    application rate in the 1990 study was at least three times greater 
    than the normal label rate.
        To be conservative, EPA decided that the values from the 1990 study 
    would be used for this risk assessment. EPA default assumptions for 
    dermal Tc, ET, SA, FQ, inhalation rates, and ingestion rates were used. 
    These defaults were used to estimate children's postapplication 
    exposure to the product Avert Prescription Treatment 310 (dry flowable 
    cockroach bait). According to Table A-1 of the SOP's for Residential 
    Exposure Assessments, the method used for estimating children's 
    postapplication exposure is believed to produce a central to high-end 
    estimate of exposure.
        Based on the information available on the study, the air and 
    surface residue values taken from the 1990 study were divided by a 
    factor of 3 to account for the exaggerated application rate used in the 
    study. The avermectin B1 residue value reported for 
    horizontal residues immediately after the application (4.2E-07 mg/
    cm2) was divided by a factor of 3 (1.4E-6 mg/cm 2) and then 
    used to estimate children's dermal and hand-to-mouth exposure. A linear 
    regression analysis was performed on the reported air concentrations at 
    0 (immediately after), 1, 3 and 7 days after the application to 
    determine the average concentration for the first 21 hours following 
    the application. The analysis indicated an average concentration of 
    avermectin B1 at 6.4E-04 mg/m3 (4% dissipation, 
    adjusted R2 = 0.986 for log-transformed data). This value was divided 
    by a factor of 3 (2.1E-4 mg/m3) and then used to estimate 
    children's inhalation exposure.
        The Short- and intermediate-term dermal MOE for children's 
    postapplication dermal is 78,000. The short- and intermediate-term oral 
    MOE for children's postapplication oral hand-to-mouth is 12,000. The 
    short- and intermediate-term inhalation MOE for children's 
    postapplication inhalation is 2,400.
        The risk from children's post application exposure to crack and 
    crevice products containing avermectin B1 does not exceed 
    EPA's level of concern. Avert Prescription Treatment 310 is a dust 
    formulation that is intended for the application to crack and crevices 
    only. Other formulations for similar crack and crevice products (i.e., 
    gels, granulars, pressurized liquids, etc.) will have less migration 
    from the treated area and are expected to result in lower risk from 
    dermal, oral, and inhalation postapplication exposure.
        4. Cumulative exposure to substances with common mechanism of 
    toxicity. Section 408(b)(2)(D)(v) 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 does not have, at this time, available data to determine 
    whether avermectin B1 and its delta-8,9-isomer has a common 
    mechanism of toxicity with other substances or how to include this 
    pesticide in a cumulative risk assessment. Unlike other pesticides for 
    which EPA has followed a cumulative risk approach based on a common 
    mechanism of toxicity, avermectin B1 and its delta-8,9-
    isomer 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 avermectin B1 and its delta-8,9-isomer 
    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 final rule for Bifenthrin Pesticide Tolerances 
    (62 FR 62961, November 26, 1997).
    
    D. Aggregate Risks and Determination of Safety for U.S. Population 
    including Infants and Children
    
        In examining aggregate exposures, FQPA directs EPA to consider 
    available information concerning exposures from the residue in food and 
    all other non-occupational exposures. The primary non-food sources of 
    exposure the Agency looks at include drinking water (whether from 
    ground or surface water), and exposure through pesticide use in 
    gardens, lawns or buildings (residential and other indoor and/or 
    outdoor uses). In evaluating food exposures, EPA takes into account 
    varying consumption patterns of major identifiable subgroups of 
    consumers, including infants and children.
        1. Acute risk. Acute aggregate exposure takes into account acute 
    dietary food and water exposure. The registrant submitted an acute 
    dietary exposure analysis using probabilistic ``Monte Carlo'' modeling. 
    EPA has examined the assumptions made in conducting the analysis and 
    has recalculated the assessment using the submitted acute file, the 
    correct acute RfD, updated PCT data, correcting the residue files above 
    to use one half the Level of Detection (LOD) or one half the Level of 
    Quantitation (LOQ) where appropriate, and using the average field trial 
    residue level and previously established processing factors for blended 
    commodities. In addition, EPA's analysis included residues in pear 
    juice for which no data has been previously required. Since all other 
    juices show reductions in avermectin B1 residues from the 
    raw agricultural commodity, EPA used the reduction factor for apples in 
    the analysis. The dietary (food only) acute %PAD range from 45% for 
    nursing infants < 1="" year="" old="" to="" 70%="" for="" children="" 1-6="" yrs.="" this="" risk="" estimate="" should="" be="" viewed="" as="" highly="" refined="" since="" it="" used="" anticipated="" residue="" values="" and="" percent="" crop-treated="" data="" in="" conjunction="" with="" monte="" carlo="" analysis.="" the="" acute="" dietary="" exposure="" does="" not="" exceed="" epa's="" level="" of="" concern.="" avermectin="">1 is a moderately persistent but non-mobile 
    compound in soil and water environments. The SCI-GROW modeling data for 
    avermectin B1 for drinking water derived from ground water 
    sources resulting from use on grapes and peppers indicate levels less 
    than OPP's DWLOC for acute exposure. Using the refined PRZM-EXAMS 
    modeling data for drinking water derived from surface water sources 
    resulting from use on strawberries (the crop with the maximum use rate) 
    also indicates levels less than OPP's DWLOC for acute exposure in all 
    populations with the exception of children 1-6 years old where the peak 
    EEC of 0.88 g/L slightly exceed this subgroup's acute DWLOC 
    (0.74 g/L).
        Despite this slight exceedance, EPA believes that acute exposure to 
    avermectin from drinking water will not pose an unacceptable risk to 
    human health. Neither surface nor ground water models used by EPA were 
    designed specifically for estimating concentrations in drinking water. 
    There are significant uncertainties in both the toxicology used to 
    derive the DWLOC and the exposure estimate from the PRZM-EXAMS model. 
    EPA has compensated for these uncertainties by using reasonable high-
    end assumptions. Given this approach, the Agency does not attach great 
    significance to such a small difference. However, EPA may do additional 
    analyses and, as a condition of product registration, the Agency will 
    require the registrant to submit (1) data
    
    [[Page 48556]]
    
    on the effects of plastic mulch on surface water pesticide 
    concentrations and (2) data characterizing the effectiveness of various 
    types of drinking water treatment on removing avermectin. These data 
    are expected to confirm that the actual concentration of avermectin in 
    drinking water is less than the level of concern for all sub-
    populations.
        2. Chronic risk. Chronic aggregate exposure takes into account 
    chronic exposure via food, water, and residential uses. Since there is 
    no chronic residential exposure to avermectin B1 only food 
    and water contributed to chronic risk.
        Using the exposure assumptions described in this notice, EPA has 
    concluded that aggregate exposure to avermectin B1 and its 
    delta-8,9-isomer from food will utilize < 1%="" of="" the="" pad="" for="" the="" u.s.="" population="" and="" will="" utilize="" from="" 6%="" to="" 17%="" of="" the="" pad="" for="" infants="" and="" children="" (depending="" on="" specific="" subgroup).="" the="" major="" identifiable="" subgroup="" with="" the="" highest="" aggregate="" exposure="" is="" non-nursing="" infants="" with="" 17%="" of="" the="" chronic="" pad.="" epa="" generally="" has="" no="" concern="" for="" exposures="" below="" 100%="" of="" the="" rfd/pad="" because="" the="" rfd/pad="" represents="" the="" level="" at="" or="" below="" which="" daily="" aggregate="" dietary="" exposure="" over="" a="" lifetime="" will="" not="" pose="" appreciable="" risks="" to="" human="" health.="" avermectin="">1 is a moderately persistent, but non-mobile 
    compound in soil and water environments. The modeling data for 
    avermectin B1 indicate chronic water residue levels less 
    than OPP's DWLOC's. EPA does not expect aggregate chronic exposure to 
    avermectin B1 will pose an unacceptable risk to human 
    health.
        3.  Short- and intermediate-term risk. Short-term aggregate 
    exposure takes into account chronic dietary food and water (considered 
    to be a background exposure level) plus short-term residential uses 
    which include dermal, inhalation, and oral exposures. For children's 
    post-application exposure from crack and crevice uses, the worst case 
    exposure scenario, risks do not exceed EPA's level of concern. The 
    residential uses that were aggregated with chronic dietary food and 
    water are from lawn and crack and crevice uses and include: (1) Adult 
    dermal exposure from the highest adult residential applicator scenario 
    (3.4E-7 mg/kg/day from belly grinder granular open pour) and crack and 
    crevice applicator scenario (2.1E-8 mg/kg/day) with exposure from post-
    application activities (3.0E-6 mg/kg/day), and inhalation from turf and 
    crack and crevice (3.9E-7 mg/kg/day). (2) Children's oral exposure from 
    turf and crack and crevice hand-to-mouth, with turf incidental 
    ingestion (3.8E-5 mg/kg/day), dermal exposure from turf and crack and 
    crevice (6.1E-6 mg/kg/day), and inhalation exposure from crack and 
    crevice (1.1E-4 mg/kg/day).
        Using the exposures above, EPA calculated the short-term DWLOCs. 
    The DWLOC of 8.2 g/L for the U.S. population is greater than 
    the water EEC's. The DWLOC for infants/children (0.77 g/L) is 
    greater than the PRZM-EXAMS chronic value of 0.57 g/L. EPA 
    does not expect aggregate short-term exposure to avermectin 
    B1 will pose an unacceptable risk to human health.
        The worst case intermediate-term exposures to avermectin 
    B1 for adults are the same as those described above for 
    short-term exposures. Using the exposures above, EPA calculated the 
    adult intermediate-term DWLOC of 8.2 g/L, which is greater 
    than the water EEC's. EPA does not expect aggregate intermediate-term 
    exposure to avermectin B1 will pose an unacceptable risk to 
    adult human health.
        The worst case intermediate-term exposures to avermectin 
    B1 for infants and children are the same as those described 
    above. Since the short- and intermediate-term NOAELs are the same, the 
    DWLOC is also equal to the 0.77 g/L short-term value. Again, 
    given the 0.57 g/L PRZM-EXAMS value, EPA is not concerned with 
    the residues in drinking water. EPA does not expect aggregate 
    intermediate-term exposure to avermectin B1 will pose an 
    unacceptable risk to human health.
        4. Aggregate cancer risk for U.S. population. EPA classified 
    avermectin B1 as a Cancer Group E chemical based on the 
    absence of significant tumor increases in two adequate rodent 
    carcinogenicity studies.
        5. Determination of safety. Based on these risk assessments, EPA 
    concludes that there is a reasonable certainty that no harm will result 
    to the U.S. population, infants, or children from aggregate exposure to 
    avermectin B1 and its delta-8,9-isomer residues.
    
    E. Determination of Safety for Infants and Children
    
        1. In general. In assessing the potential for additional 
    sensitivity of infants and children to residues of avermectin 
    B1 and its delta-8,9-isomer, EPA considered data from 
    developmental toxicity studies in the rat and rabbit and a 2-generation 
    reproduction study in the rat. The developmental toxicity studies are 
    designed to evaluate adverse effects on the developing organism 
    resulting from maternal pesticide exposure gestation. Reproduction 
    studies provide information relating to effects from exposure to the 
    pesticide on the reproductive capability of mating animals and data on 
    systemic toxicity.
        FFDCA section 408 provides that EPA shall apply an additional 
    tenfold margin of safety for infants and children in the case of 
    threshold effects to account for pre- and postnatal toxicity and the 
    completeness of the database unless EPA determines 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 margin of exposure (MOE) analysis or through using 
    uncertainty (safety) factors in calculating a dose level that poses no 
    appreciable risk to humans. EPA believes that reliable data support 
    using the standard uncertainty factor (usually 100 for combined inter- 
    and intra-species variability) and not the additional tenfold MOE/
    uncertainty factor when EPA has a complete data base under existing 
    guidelines and when the severity of the effect in infants or children 
    or the potency or unusual toxic properties of a compound do not raise 
    concerns regarding the adequacy of the standard MOE/safety factor.
         2. Developmental toxicity studies.  Studies are discussed in Unit 
    III.A.4 of this preamble.
         3. Reproductive toxicity study. Studies are discussed in Unit 
    III.A.4 of this preamble.
         4. Pre- and postnatal sensitivity. There was evidence of increased 
    susceptibility to the offspring following pre- and postnatal exposure 
    to avermectin B1 in the 2-generation reproduction study in 
    rats.
         5. Conclusion. There is a complete toxicity database for 
    avermectin B1 and its delta-8,9-isomer and exposure data is 
    complete or is estimated based on data that reasonably accounts for 
    potential exposures. The Agency is retaining the 10-fold safety factor 
    for increased susceptibility of infants and children for this pesticide 
    and is applying it to females 13+, infants, and children population 
    subgroups for acute, chronic, and residential exposure.
         The 10x Safety Factor is being retained because:
        (1) There was evidence of increased susceptibility to the offspring 
    following pre- and postnatal exposure to avermectin B1 in 
    the two-generation reproduction study in rats.
        (2) There is evidence of neurotoxicity manifested as clinical signs 
    of neurotoxicity in mice, rats, and dogs in developmental, 
    reproduction, chronic and/or carcinogenicity studies in mice, rats and/
    or dogs.
    
    [[Page 48557]]
    
        (3) There is concern for Structure Activity Relationship: 
    ivermectin induced cleft palate in fetal rats, and cleft palate and 
    clubbed forefoot in fetal rabbits.
        (4) EPA determined that a developmental neurotoxicity study in rats 
    is required for avermectin B1. This study could provide 
    additional information on potential increased susceptibility, effects 
    on the development of the fetal nervous system, as well as the 
    functional development of the young.
        (5) There is concern for post-application exposure to infants and 
    children in treated areas, including incidental hand-to-mouth ingestion 
    of the pesticide.
    
    IV. Other Considerations
    
    A. Metabolism In Plants and Animals
    
        Plant metabolism data have been previously submitted on cotton 
    seed, citrus, and celery. In addition, a report titled ``Comparative 
    Degradation of Avermectin B1a in Cotton Leaf, Citrus Fruit, 
    Celery, and In Vitro'' was submitted. The proposed use in this petition 
    on grapes and chili peppers specifies multiple applications up to a 
    maximum application rate on grapes of 32 fl oz/A/season (0.038 lb ai/A/
    season) and on peppers of 48 oz/A/season (0.057 lb ai/A/season). 
    Previously, the metabolism components have been examined from radio-
    labeled avermectin B1 on celery (10 applications at 7 day 
    intervals for a total equivalent of 1.0 lb ai/A/season), radio-labeled 
    avermectin B1 on cotton (3 applications at 50 to 89 day 
    intervals for a total equivalent of 0.60 lb/A/season), and exaggerated 
    application rates to citrus (30X, 2.25 lb ai/A). The available 
    metabolism data on cotton, celery, and citrus represent a wide enough 
    range of crop matrices, growth modes, and use rates. It is unlikely 
    that application of avermectin B1 to grapes and chili 
    peppers will result in new degradation compounds that have not 
    previously been produced and subjected to toxicity testing. EPA 
    concludes that the metabolism data are sufficient (a) to support the 
    proposed use on grapes and chili peppers and (b) to support the 
    recommended tolerance on cotton gin byproducts. The residues of concern 
    in/on grapes, chili pepper, and cotton gin byproduct commodities are 
    the parent compound (avermectin B1a and B1b) and 
    its delta-8,9-isomer.
        Since there are no grape or chili pepper animal feed items of 
    regulatory concern, a discussion of animal metabolism is not germane to 
    petition PP 7F4844.
        Animal metabolism data were not submitted in conjunction with 
    cotton petition (PP 7F3500). However, the metabolism of avermectin in 
    goat and rat has been reviewed. From these studies, it was determined 
    that the residues of concern in ruminants are avermectin B1a 
    and B1b and their delta-8,9-isomers. This conclusion was 
    based upon a feeding level of 1.0 mg/goat/day of 3H-
    avermectin. An additional metabolite (24-hydroxymethyl avermectin 
    B1a) was identified and is potentially of toxicological 
    significance, but was not included in the tolerance expression because 
    of its presence at low levels. However, EPA notes that if the livestock 
    dietary burden is increased and the tolerances for residues in meat and 
    milk need to be raised, then the 24-hydroxymethyl metabolite may need 
    to be included in the tolerance expression and appropriate enforcement 
    methods would need to be developed. Furthermore, an additional animal 
    metabolism study using 14C-avermectin would be needed if the 
    expected ruminant dietary burden exceeded the dose level in the 
    previously submitted goat metabolism study. EPA concludes the available 
    ruminant metabolism study is adequate to support the proposed 
    tolerances for avermectin on cotton gin byproducts.
        Cotton gin byproducts are not a poultry feed item. Therefore a 
    discussion of metabolism and secondary residues in poultry commodities 
    is not pertinent to petition PP 7F3500.
    
    B. Analytical Enforcement Methodology
    
        The registrant has used the analytical procedure designated Method 
    91-1 for data gathering purposes in these grape and chili pepper field 
    trials for avermectin B1 and its delta-8,9-isomer. 
    Acceptable independent method validations (ILV) were submitted for both 
    commodities. The samples are extracted with acetonitrile/water/hexane, 
    cleaned up with an aminopropyl column, and derivatized with 
    trifluoroacetic anhydride. Quantitation of the residues of interest is 
    accomplished by high performance liquid chromatography (HPLC) with 
    fluorescence detector. The LOQ varies from .001 ppm for grapes to .004 
    ppm for chili peppers. Method 91-1 is adequate for data collection 
    purposes. Method 91-1 is somewhat similar to the registrant's method 
    for hops, Method M-036.2, which has been submitted for inclusion in 
    FDA's PAM II. Since they are similar, Method M-036.2 is adequate for 
    tolerance enforcement.
        Residues of avermectin B1 and 8,9-Z avermectin 
    B1 in cotton gin byproducts were determined using a 
    modification of Method M-078. Samples are extracted with a methanol-
    water mixture. The avermectins are partitioned into hexane and the 
    hexane extract is purified/concentrated on an NH2 SPE column. The 
    purified extract is derivatized with trifluoroacetic anhydride. The 
    derivatized avermectins are analyzed by reversed phase HPLC with 
    fluorescence detection. The avermectin B1a standard is used 
    to calculate the concentration of avermectin B1a + 8,9-Z 
    avermectin B1a and avermectin B1b + 8,9-Z 
    avermectin B1b in/on the sample. The modifications made to 
    Method M-078 included using a higher HPLC flow rate, preparing the 
    standard solutions at different concentrations, centrifuging the 
    samples with emulsions after shaking, and using equipment, apparatus, 
    and chemical manufacturers which were different from those specified in 
    the method. The limit of detection (LOD) is 0.001 ppm; the LOQ is 0.002 
    ppm. The method was validated by fortifying control gin trash samples 
    and analyzing them concurrently with the treated and control samples. 
    Method M-078 is very similar to the registrant's method for hops, 
    Method M-036.2, which has been submitted for inclusion in FDA's PAM II. 
    Since they are very similar and method recovery is good, Method M-078 
    is adequate for enforcement purposes.
        Merck Method 32A is available for enforcing avermectin tolerances 
    in bovine tissues and milk. This method has been published in PAM II 
    (Method II).
        Avermectin B1 is not recovered using FDA multi-residue 
    protocol A described in PAM I.
    
    C. Magnitude of Residues
    
        The residue field trial data on grapes submitted with this petition 
    are adequate to support the proposed use. The highest residue found on 
    grapes at the 28-day pre-harvest interval (PHI) was 6.7 ppb (0.007 
    ppm). This supports the tolerance of 0.02 ppm proposed by the 
    registrant.
        The residue field trial data on chili peppers submitted with this 
    petition are adequate to support the proposed use. The highest residue 
    found on chili peppers at the 7- day PHI was < 5="" parts="" per="" billion="" (ppb)="">< 0.005="" ppm).="" this="" supports="" the="" tolerance="" of="" 0.01="" ppm="" on="" peppers="" proposed="" by="" the="" registrant.="" however,="" the="" originally="" submitted="" section="" f="" lists="" chili="" peppers="" not="" peppers.="" in="" order="" to="" harmonize="" with="" international="" residue="" limits="" discussed="" below,="" the="" section="" f="" was="" revised="" to="" express="" the="" tolerance="" as="" 0.02="" ppm="" on="" peppers.="" [[page="" 48558]]="" the="" grape="" processing="" study="" and="" existing="" storage="" stability="" database="" are="" adequate="" to="" support="" the="" proposed="" tolerance="" on="" juice.="" the="" highest="" residues="" found="" on="" commodities="" of="" regulatory="" concern="" were="">< 2="" ppb="">< 0.002="" ppm)="" in="" juice.="" this="" supports="" the="" requested="" tolerance="" of="" 0.02="" ppm="" on="" grape="" juice.="" however,="" since="" the="" processing="" study="" shows="" that="" avermectin="">1 does not concentrate in juice, a tolerance on 
    grape juice is not required.
        Starting with raw grapes bearing residues of 10 ppb, the highest 
    avermectin B1 residues found on raisins were 10.2 ppb (0.01 
    ppm). The results of the raisin storage stability study indicate that 
    the residues in raisins could have been as high as 20 ppb (2x 
    concentration factor, based on < 50%="" recoveries).="" using="" this="" concentration="" factor="" and="" the="" highest="" grape="" field="" trial="" value="" of="" 0.007="" ppm,="" residues="" in="" raisins="" would="" be="" 0.014="" ppm="" versus="" the="" grape="" tolerance="" of="" 0.02="" ppm.="" therefore,="" even="" taking="" into="" account="" the="" poor="" recoveries="" from="" the="" raisin="" storage="" stability="" study,="" a="" tolerance="" for="" raisins="" is="" not="" necessary.="" since="" tolerances="" are="" not="" needed="" for="" processed="" grape="" food="" items,="" the="" section="" f="" was="" revised="" to="" express="" the="" tolerance="" as="" grapes.="" there="" are="" no="" chili="" pepper="" processed="" food="" items;="" therefore="" a="" discussion="" of="" processed="" food="" items="" is="" not="" germane="" to="" this="" action.="" since="" there="" are="" no="" grape="" or="" pepper="" animal="" feed="" items="" of="" regulatory="" interest,="" secondary="" avermectin="">1 residues in meat, milk, 
    poultry, and eggs will not be increased by the proposed tolerances for 
    these crops.
        To support the tolerance on cotton gin byproducts, the petitioner 
    has submitted the results of eight field trials on cotton using the 
    maximum labeled rate. The existing storage stability database is 
    adequate to support the cotton gin byproduct analyses. The highest 
    residue level obtained was 0.101 ppm. The PHI was slightly longer than 
    that specified on the label, however. The label specifies a PHI of 20 
    days; the PHI used in the field trails was 25 days. EPA has concluded 
    that the data support the establishment of a tolerance of 0.15 ppm for 
    the residues of avermectin in/on cotton gin byproducts.
        Since cotton gin byproducts are a feed item for some livestock an 
    analysis was performed to calculate the dietary burden in these 
    animals. Cotton gin byproducts are not a feed item for poultry or 
    swine; these commodities were not included in the analysis. Cotton gin 
    byproducts can comprise up to 20% of the diets of both beef and dairy 
    cattle. The following animal feed items are associated with commodities 
    with avermectin registrations: almond hulls, wet apple pomace, dried 
    citrus pulp, cotton seed, potato culls, and potato waste. Of these 
    commodities, cotton seed meal is the only highly nutritive one. The 
    others mainly provide fiber to the diet. Cotton seed meal will be 
    distributed to all parts of the country, but the others will not. 
    Therefore, it is reasonable to construct a dietary burden with cotton 
    seed meal and only one of the other ``esoteric'' feed items. Wet apple 
    pomace would contribute the highest residues to the diet, therefore a 
    dietary burden was constructed using cotton seed meal and apple pomace. 
    The feeding study was done at 3 different feeding levels: 0.010 ppm, 
    0.030 ppm, and 0.10 ppm. The dietary burden constructed with cotton 
    seed and apple pomace is essentially the same as the highest feeding 
    level: 0.10 ppm. The established tolerances are adequate to cover this 
    dietary burden. As the tolerances will not change, it is not necessary 
    to perform a dietary exposure analysis. EPA concludes that residues 
    present in animal commodities will not increase over current levels. 
    Therefore, it is not necessary to increase the established tolerances 
    for animal commodities. Furthermore, the establishment of a tolerance 
    for cotton gin byproducts does not affect risk to human health as 
    animal commodity tolerances will not be affected by the establishment 
    of this tolerance.
    
    D. International Residue Limits
    
        There are no Codex, Canadian, or Mexican Maximum Residue Limits 
    (MRL) for avermectin B1 on grapes, grape processed 
    commodities. Therefore, international harmonization is not an issue for 
    the action on grapes.
        There are no Canadian or Mexican MRLs for avermectin B1 
    on peppers. There is a Codex MRL for avermectin B1a, 
    B1b, (Z)-8,9-avermectin B1a, and (Z)-8,9-
    avermectin B1b on sweet peppers at 0.02 ppm. The regulable 
    residues for the U.S. and Codex are identical. In order to harmonize 
    with this MRL, the Section F was revised to express the tolerance for 
    avermectin B1 and its delta-8.9-isomer as 0.02 ppm on 
    peppers.
        There are no Codex, Canadian, or Mexican MRLs for avermectin 
    B1 on cotton gin by-products. Therefore, international 
    harmonization is not an issue for cotton gin by-products. A Codex MRL 
    has been established for cotton seed: 0.01 ppm. This MRL differs from 
    the proposed permanent tolerance for cotton seed: 0.005 ppm.
    
    E. Rotational Crop Restrictions 
    
        Review of the results of the confined rotational crop study 
    indicated that avermectin B1 residues accumulated in some 
    rotational crops at levels up to 10 - 12 ppb. However, the 
    radioactivity was due to polar degradates that were of little 
    toxicological concern as compared to the parent compound avermectin 
    B1 and/or the delta-8,9-isomer. Therefore, the requirements 
    for field rotational crop studies have been waived.
    
    V. Conclusion
    
        Therefore, the tolerance is established for combined residues of 
    the insecticide avermectin B1 (a mixture of avermectins 
    containing greater than or equal to 80% avermectin B1a (5-O-
    demethyl avermectin A1) and less than or equal to 20% 
    avermectin B1b (5-O-demethyl-25-de(1-methylpropyl)-25-(1-
    methylethyl) avermectin A1)) and its delta-8,9-isomer in 
    grapes at 0.02 ppm, peppers at 0.02 ppm, and cotton gin byproducts at 
    0.15 ppm. Furthermore, the following tolerances which were previously 
    time-limited (expiring September 1, 1999) are now made permanent: 
    cattle, fat at 0.015 ppm; cattle, meat byproducts at 0.02 ppm; cattle, 
    meat at 0.02 ppm; citrus, dried pulp at 0.10 ppm; citrus, oil at 0.10 
    ppm; citrus, whole fruit at 0.02 ppm; cotton seed at 0.005 ppm; hops, 
    dried at 0.20 ppm; milk at 0.005 ppm; and potatoes at 0.005 ppm.
    
    VI. Objections and Hearing Requests
    
        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. Although the procedures in those 
    regulations require some modification to reflect the amendments made to 
    the FFDCA by the FQPA of 1996, EPA will continue to use those 
    procedures, with appropriate adjustments, until the necessary 
    modifications can be made. The new section 408(g) provides essentially 
    the same process for persons to ``object'' to a regulation for an 
    exemption from the requirement of a tolerance issued by EPA under new 
    section 408(d), as was provided in the old FFDCA sections 408 and 409. 
    However, the period for filing objections is now 60 days, rather than 
    30 days.
    
     A. What Do I Need to Do to File an Objection or Request a Hearing? 
    
        You must file your objection or request a hearing on this 
    regulation in accordance with the instructions provided in this unit 
    and in 40 CFR part 178. To ensure proper receipt by EPA, you must 
    identify docket control number OPP-300916 in the subject line
    
    [[Page 48559]]
    
    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 
    November 8, 1999.
        1. Filing the request. Your objection must specify the specific 
    provisions in the regulation that you object to, and the grounds for 
    the objections (40 CFR 178.25). If a hearing is requested, the 
    objections must include a statement of the factual issues(s) on which a 
    hearing is requested, the requestor's contentions on such issues, and a 
    summary of any evidence relied upon by the objector (40 CFR 178.27). 
    Information submitted in connection with an objection or hearing 
    request may be claimed confidential by marking any part or all of that 
    information as CBI. Information so marked will not be disclosed except 
    in accordance with procedures set forth in 40 CFR part 2. A copy of the 
    information that does not contain CBI must be submitted for inclusion 
    in the public record. Information not marked confidential may be 
    disclosed publicly by EPA without prior notice.
        Mail your written request to: Office of the Hearing Clerk (1900), 
    Environmental Protection Agency, 401 M St. SW. Washington, DC 20460. 
    You may also deliver your request to the Office of the Hearing Clerk in 
    Room M3708, Waterside Mall, 401 M St. SW. Washington, DC 20460. The 
    Office of the Hearing Clerk is open from 8 a.m. to 4 p.m. Monday 
    through Friday, excluding legal holidays. The telephone number for the 
    Office of the Hearing Clerk is (202) 260-4865.
        2.  Tolerance fee payment. If you file an objection or request a 
    hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or 
    request a waiver of that fee pursuant to 40 CFR 180.33(m). You must 
    mail the fee to: EPA Headquarters Accounting Operations Branch, Office 
    of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please 
    identify the fee submission be labeling it ``Tolerance Petition Fees.''
        EPA is authorized to waive any fee requirement ''when in the 
    judgement of the Administrator such a waiver or refund is equitable and 
    not contrary to the purpose of this subsection.'' (cite). For 
    additional information regarding the waiver of these fees, you may 
    contact James Tompkins by phone at (703) 305-5697, by e-mail at 
    tompkins.jim@epa.gov, or by mailing a request for information to Mr. 
    Tompkins at Registration Division (7505C), Office of Pesticide 
    Programs, Environmental Protection Agency, 401 M St. SW., Washington, 
    DC 20460.
        If you would like to request a waiver of the tolerance objection 
    fees, you must mail your request for such a waiver to: James Hollins, 
    Information Resources and Services Division (7502C), Office of 
    Pesticide Programs, Environmental Protection Agency, 401 M St. SW. 
    Washington, DC 20460.
        3. Copies for the Docket. In addition to filing an objection or 
    hearing request with the Hearing Clerk as described in Unit VI.A. of 
    this preamble, you should also send a copy of your request to the PIRB 
    for its inclusion in the official record that is described in Unit 
    I.B.2. of this preamble. Mail your copies, identified by docket number 
    OPP-300916, to: Public Information and Records Integrity Branch, 
    Information Resources and Services Division (7502C), Office of 
    Pesticide Programs, Environmental Protection Agency, 401 M St. SW. 
    Washington, DC 20460. In person or by courier, bring a copy to the 
    location of the PRIB described in Unit I.B.2. of this preamble. You may 
    also send an electronic copy of your request via e-mail to: docket@epa.gov. Please use an ASCII file format and avoid the use of 
    special characters and any form of encryption. Copies of electronic 
    objections and hearing requests will also be accepted on disks in 
    WordPerfect 5.1/6.1 file format or ASCII file format. Do not include 
    any CBI in your electronic copy. You may also submit an electronic copy 
    of your request at many Federal Depository Libraries.
    
    B. When Will the Agency Grant a Request for a Hearing?
    
        A request for a hearing will be granted if the Administrator 
    determines that the material submitted shows the following: There is a 
    genuine and substantial issue of fact; there is a reasonable 
    possibility that available evidence identified by the requestor would, 
    if established resolve one or more of such issues in favor of the 
    requestor, taking into account uncontested claims or facts to the 
    contrary; and resolution of the factual issues(s) in the manner sought 
    by the requestor would be adequate to justify the action requested (40 
    CFR 178.32).
    
    VII. Regulatory Assessment Requirements
    
        This final rule establishes tolerances under section 408(d) of the 
    FFDCA 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). 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., or impose any enforceable 
    duty or contain any unfunded mandate as described under Title II of the 
    Unfunded Mandates Reform Act of 1995 (UMRA) (Public Law 104-4). Nor 
    does it require prior consultation with State, local, and tribal 
    government officials as specified by Executive Order 12875, entitled 
    Enhancing the Intergovernmental Partnership (58 FR 58093, October 28, 
    1993) and Executive Order 13084, entitled Consultation and Coordination 
    with Indian Tribal Governments (63 FR 27655, May 19,1998), or special 
    consideration of environmental justice related issues under Executive 
    Order 12898, entitled Federal Actions to Address Environmental Justice 
    in Minority Populations and Low-Income Populations (59 FR 7629, 
    February 16, 1994), or require OMB review in accordance with Executive 
    Order 13045, entitled Protection of Children from Environmental Health 
    Risks and Safety Risks (62 FR 19885, April 23, 1997). The Agency has 
    determined that this action will not have a substantial direct effect 
    on States, on the relationship between the national government and the 
    States, or on the distribution of power and responsibilities among the 
    various levels of government, as specified in Executive Order 12612, 
    entitled Federalism (52 FR 41685, October 30, 1987). This action 
    directly regulates growers, food processors, food handlers and food 
    retailers, not States. This action does not alter the relationships or 
    distribution of power and responsibilities established by Congress in 
    the preemption provisions of the Federal Food, Drug, and Cosmetic Act, 
    21 U.S.C. section 346a(b)(4). 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), Public Law 
    104-113, section 12(d) (15 U.S.C. 272 note). In addition, since 
    tolerances and exemptions that are established on the basis of a 
    petition under FFDCA section 408(d), such as the tolerances 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.
    
    VIII. Submission to Congress and the Comptroller General
    
        The Congressional Review Act, 5 U.S.C. 801 et seq. as added by the 
    Small Business Regulatory Enforcement Fairness Act of 1996, generally 
    provides that before a rule may take effect, the agency promulgating 
    the rule must submit a rule report, which includes a
    
    [[Page 48560]]
    
    copy of the rule, to each House of the Congress and to the Comptroller 
    General of the United States. 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 this rule in the Federal Register. This rule is 
    not a ``major rule'' as defined by 5 U.S.C. 804(2).
    
    List of Subjects in 40 CFR Part 180
    
        Environmental protection, Administrative practice and procedure, 
    Agricultural commodities, Pesticides and pests, Reporting and 
    recordkeeping requirements.
    
        Dated: August 31, 1999.
    
    Richard P. Keigwin, Jr.,
    
    Acting Director, Registration Division, Office of Pesticide Programs.
         Therefore, 40 CFR chapter I is amended as follows:
    
    PART 180--[AMENDED]
    
        1. The authority citation for part 180 continues to read as 
    follows:
        Authority: 21 U.S.C. 321(q), (346a), and 371.
    
    
        2. Section 180.449 is amended by revising paragraph (a) to read as 
    follows:
    
    
    Sec. 180.449   Avermectin B1 and its delta-8,9-isomer; 
    tolerances for residues.
    
        (a) General. Tolerances are established for the combined residues 
    of the insecticide avermectin B1 (a mixture of avermectins 
    containing greater than or equal to 80% avermectin B1a (5-O-
    demethyl avermectin A1) and less than or equal to 20% 
    avermectin B1b (5-O-demethyl-25-de(1-methylpropyl)-25-(1-
    methylethyl) avermectin A1)) and its delta-8,9-isomer in or 
    on the following commodities:
    
    ------------------------------------------------------------------------
                                                                  Parts per
                             Commodity                             million
    ------------------------------------------------------------------------
    Almonds....................................................        0.005
    Almond, hulls..............................................         0.10
    Apples.....................................................        0.020
    Apples, pomace (wet).......................................         0.10
    Cattle, fat................................................        0.015
    Cattle, mbyp...............................................         0.02
    Cattle, meat...............................................         0.02
    Celery.....................................................         0.05
    Citrus, dried pulp.........................................         0.10
    Citrus, oil................................................         0.10
    Citrus whole fruit.........................................         0.02
    Cotton gin by-products.....................................         0.15
    Cotton seed................................................        0.005
    Cucurbits (cucumbers, mellons, and squashes)...............        0.005
    Grapes.....................................................         0.02
    Hops, dried................................................         0.20
    Lettuce, head..............................................         0.05
    Milk.......................................................        0.005
    Pears......................................................         0.02
    Peppers....................................................         0.02
    Potatoes...................................................        0.005
    Strawberry.................................................         0.02
    Tomatoes, fresh............................................         0.01
    Walnuts....................................................        0.005
    ------------------------------------------------------------------------
    
    * * * * *
    
    [FR Doc. 99-23194 Filed 9-3-99; 8:45 am]
    BILLING CODE 6560-50-F
    
    
    

Document Information

Effective Date:
9/7/1999
Published:
09/07/1999
Department:
Environmental Protection Agency
Entry Type:
Rule
Action:
Final rule.
Document Number:
99-23194
Dates:
This regulation is effective September 7, 1999. Objections and requests for hearings, identified by docket control number OPP-300916, must be received by EPA on or before November 8, 1999.
Pages:
48548-48560 (13 pages)
Docket Numbers:
OPP-300916, FRL-6380-7
RINs:
2070-AB78
PDF File:
99-23194.pdf
CFR: (1)
40 CFR 180.449