97-31920. Fluorine Compounds; Time-Limited Pesticide Tolerance  

  • [Federal Register Volume 62, Number 234 (Friday, December 5, 1997)]
    [Rules and Regulations]
    [Pages 64294-64301]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-31920]
    
    
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    ENVIRONMENTAL PROTECTION AGENCY
    
    40 CFR Part 180
    
    [OPP-300586; FRL-5756-5]
    RIN 2070-AB78
    
    
    Fluorine Compounds; Time-Limited Pesticide Tolerance
    
    AGENCY: Environmental Protection Agency (EPA).
    
    ACTION: Final rule.
    
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    SUMMARY: This regulation establishes a time-limited tolerance for 
    residues of the insecticidal fluorine compounds cryolite and/or 
    synthetic cryolite (sodium aluminum fluoride) in or on the raw 
    agricultural commodity (RAC) potatoes and in the processed animal feed 
    commodity, potato waste. A petition requesting these tolerances was 
    submitted by The Cryolite Task Force under the Federal Food Drug and 
    Cosmetic Act (FFDCA) as amended by the Food Quality Protection Act of 
    1996 (Pub. L. 104-170). The tolerance will expire on November 21, 2001.
    
    DATES: This regulation is effective December 5, 1997. Objections and 
    requests for hearings must be received by EPA on or before February 3, 
    1998.
    
    ADDRESSES: Written objections and hearing requests, identified by the 
    document control number, OPP-300586, must be submitted to: Hearing 
    Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M St., 
    SW., Washington, DC 20460. Fees accompanying objections and hearing 
    requests shall be labeled ``Tolerance Petition Fees'' and forwarded to: 
    EPA Headquarters Accounting Operations Branch, OPP (Tolerance Fees), 
    P.O. Box 360277M, Pittsburgh, PA 15251. A copy of any objections and 
    hearing requests filed with the Hearing Clerk identified by the 
    document control number, [OPP-300586], must be submitted 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, 
    bring a copy of objections and hearing requests to Rm. 1132, Crystal 
    Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA 22202.
        A copy of objections and hearing requests filed with the Hearing 
    Clerk may also be submitted electronically by sending electronic mail 
    (e-mail) to: OPP-docket@epamail.epa.gov. Copies of objections and 
    hearing requests must be submitted as an ASCII file avoiding the use of 
    special characters and any form of encryption. Copies of objections and 
    hearing requests will also be accepted on disks in WordPerfect 5.1 file 
    format or ASCII file format. All copies of objections and hearing 
    requests in electronic form must be identified by the docket number 
    [OPP-300586]. No Confidential Business Information (CBI) should be 
    submitted through e-mail. Electronic copies of objections and hearing 
    requests on this rule may be filed online at many Federal Depository 
    Libraries.
    
    FOR FURTHER INFORMATION CONTACT: By mail: Jacqueline Mosby, 
    Environmental Scientist, Registration Division 7505C, Office of 
    Pesticide Programs, Environmental Protection Agency, 401 M St., SW., 
    Washington, DC 20460. Office location, telephone number, and e-mail 
    address: Crystal Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA, 
    (703) 305-6792, e-mail: mosby-romney.jackie2epamail.epa.gov.
    
    SUPPLEMENTARY INFORMATION: EPA issued notices as follows regarding 
    petitions for pesticide tolerances for insecticidal fluorine compounds 
    in or on potatoes and in the processed animal feed, potato waste.
        1. March 23, 1989 (54 FR 12009); PP 9F3739; filing notice;
        2. April 3, 1991 (56 FR 13643); PP 1F3959 and FAP 1H5604; filing 
    notice.
        3. May 5, 1993 (58 FR 26687); PP 9F3739 and FAP 1H5604; final rule 
    for time-limited tolerances.
        4. May 8, 1996 (61 FR 20781) (FRL-5362-6); PP 9F3739 and FAP 
    1H5604); proposed rule for permanent tolerances.
        The Agency did not publish a final rule establishing permanent 
    tolerances prior to the enactment of the Food Quality and Protection 
    Act (FQPA) of 1996. Because of new procedures under FQPA, The Cryolite 
    Task Force, c/o Gowan Company, P.O. Box 5569, Yuma, AZ 85336 was 
    required to submit a notice of filing requesting issuance of these 
    tolerances in compliance with FQPA.
        In the Federal Register of March 12, 1997 (62 FR 11437) EPA issued 
    a notice of filing pursuant to section 408 of the Federal Food, Drug 
    and Cosmetic Act (FFDCA), 21 U.S.C. 346a(e) announcing the filing of a 
    pesticide petition (PP) for tolerance by The Cryolite Task Force. This 
    notice contained a summary of the petition prepared by The Cryolite 
    Task Force.
        The petition requested that 40 CFR 180.145 be amended by 
    establishing tolerances for residues of the insecticidal fluorine 
    compounds cryolite and synthetic cryolite in or on potatoes at 2.0 
    parts per million (ppm) and processed potato waste at 22.0 ppm. These 
    tolerances will expire on November 21, 2001.
    
    I. Risk Assessment and Statutory Findings
    
        New 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
    
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    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. First, EPA determines the 
    toxicity of pesticides based primarily on toxicological studies using 
    laboratory animals. These studies address many adverse health effects, 
    including (but not limited to) reproductive effects, developmental 
    toxicity, toxicity to the nervous system, and carcinogenicity. Second, 
    EPA examines exposure to the pesticide through the diet (e.g., food and 
    drinking water) and through exposures that occur as a result of 
    pesticide use in residential settings.
    
    A. Toxicity
    
        1. Threshold and non-threshold effects. For many animal studies, a 
    dose response relationship can be determined, which provides a dose 
    that causes adverse effects (threshold effects) and doses causing no 
    observed effects (the ``no-observed effect level'' or ``NOEL'').
        Once a study has been evaluated and the observed effects have been 
    determined to be threshold effects, EPA generally divides the NOEL from 
    the study with the lowest NOEL by an uncertainty factor (usually 100 or 
    more) to determine the Reference Dose (RfD). The RfD is a level at or 
    below which daily aggregate exposure over a lifetime will not pose 
    appreciable risks to human health. An uncertainty factor (sometimes 
    called a ``safety factor'') of 100 is commonly used since it is assumed 
    that people may be up to 10 times more sensitive to pesticides than the 
    test animals, and that one person or subgroup of the population (such 
    as infants and children) could be up to 10 times more sensitive to a 
    pesticide than another. In addition, EPA assesses the potential risks 
    to infants and children based on the weight of the evidence of the 
    toxicology studies and determines whether an additional uncertainty 
    factor is warranted. Thus, an aggregate daily exposure to a pesticide 
    residue at or below the RfD (expressed as 100% or less of the RfD) is 
    generally considered acceptable by EPA. EPA generally uses the RfD to 
    evaluate the chronic risks posed by pesticide exposure. For shorter 
    term risks, EPA calculates a margin of exposure (MOE) by dividing the 
    estimated human exposure into the NOEL from the appropriate animal 
    study. Commonly, EPA finds MOEs lower than 100 to be unacceptable. This 
    100-fold MOE is based on the same rationale as the 100-fold uncertainty 
    factor.
        Lifetime feeding studies in two species of laboratory animals are 
    conducted to screen pesticides for cancer effects. When evidence of 
    increased cancer is noted in these studies, the Agency conducts a 
    weight of the evidence review of all relevant toxicological data 
    including short-term and mutagenicity studies and structure activity 
    relationship. Once a pesticide has been classified as a potential human 
    carcinogen, different types of risk assessments (e.g., linear low dose 
    extrapolations or MOE calculation based on the appropriate NOEL) will 
    be carried out based on the nature of the carcinogenic response and the 
    Agency's knowledge of its mode of action.
        2. Differences in toxic effect due to exposure duration. The 
    toxicological effects of a pesticide can vary with different exposure 
    durations. EPA considers the entire toxicity data base, and based on 
    the effects seen for different durations and routes of exposure, 
    determines which risk assessments should be done to assure that the 
    public is adequately protected from any pesticide exposure scenario. 
    Both short and long durations of exposure are always considered. 
    Typically, risk assessments include ``acute,'' ``short-term,'' 
    ``intermediate term,'' and ``chronic'' risks. These assessments are 
    defined by the Agency as follows.
        Acute risk, by the Agency's definition, results from 1-day 
    consumption of food and water, and reflects toxicity which could be 
    expressed following a single oral exposure to the pesticide residues. 
    High end exposure to food and water residues are typically assumed.
        Short-term risk results from exposure to the pesticide for a period 
    of 1-7 days, and therefore overlaps with the acute risk assessment. 
    Historically, this risk assessment was intended to address primarily 
    dermal and inhalation exposure which could result, for example, from 
    residential pesticide applications. However, since enaction of FQPA, 
    this assessment has been expanded to include both dietary and non-
    dietary sources of exposure, and will typically consider exposure from 
    food, water, and residential uses when reliable data are available. In 
    this assessment, risks from average food and water exposure, and high-
    end residential exposure, are aggregated. High-end exposures from all 3 
    sources are not typically added because of the very low probability of 
    this occurring in most cases, and because the other conservative 
    assumptions built into the assessment assure adequate protection of 
    public health. However, for cases in which high-end exposure can 
    reasonably be expected from multiple sources (e.g. frequent and 
    widespread homeowner use in a specific geographical area), multiple 
    high-end risks will be aggregated and presented as part of the 
    comprehensive risk assessment/characterization. Since the toxicological 
    endpoint considered in this assessment reflects exposure over a period 
    of at least 7 days, an additional degree of conservatism is built into 
    the assessment; i.e., the risk assessment nominally covers 1-7 days 
    exposure, and the toxicological endpoint/NOEL is selected to be 
    adequate for at least 7 days of exposure. (Toxicity results at lower 
    levels when the dosing duration is increased.)
        Intermediate-term risk results from exposure for 7 days to several 
    months. This assessment is handled in a manner similar to the short-
    term risk assessment.
        Chronic risk assessment describes risk which could result from 
    several months to a lifetime of exposure. For this assessment, risks 
    are aggregated considering average exposure from all sources for 
    representative population subgroups including infants and children.
    
    B. Aggregate Exposure
    
        In examining aggregate exposure, FFDCA section 408 requires that 
    EPA take into account available and reliable information concerning 
    exposure from the pesticide residue in the food in question, residues 
    in other foods for which there are tolerances, residues in groundwater 
    or surface water that is consumed as drinking water, and other non-
    occupational exposures through pesticide use in gardens, lawns, or 
    buildings (residential and other indoor uses). Dietary exposure to 
    residues of a pesticide in a food commodity are estimated by 
    multiplying the average daily consumption of the food forms of that 
    commodity by the tolerance level or the anticipated pesticide residue 
    level. The Theoretical Maximum Residue Contribution (TMRC) is an 
    estimate of the level of residues consumed daily if each food item 
    contained pesticide residues equal to the tolerance. In evaluating food 
    exposures, EPA takes into account varying consumption patterns of major 
    identifiable subgroups of consumers, including infants and children. 
    The TMRC is a ``worst case'' estimate since it is based on the 
    assumptions that food contains pesticide residues at the tolerance 
    level and that 100% of the crop is treated by pesticides that have 
    established
    
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    tolerances. If the TMRC exceeds the RfD or poses a lifetime cancer risk 
    that is greater than approximately one in a million, EPA attempts to 
    derive a more accurate exposure estimate for the pesticide by 
    evaluating additional types of information (anticipated residue data 
    and/or percent of crop treated data) which show, generally, that 
    pesticide residues in most foods when they are eaten are well below 
    established tolerances.
    
    II. 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 cryolite 
    and to make a determination on aggregate exposure, consistent with 
    section 408(b)(2), for a time-limited tolerance for residues of 
    cryolite on potatoes at 2.0 ppm, and processed potato waste at 22.0 
    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 cryolite are 
    discussed below.
        1.  Acute toxicity studies. Oral, dermal, and inhalation studies 
    place cryolite in toxicity category III, for acute dermal and in 
    category IV for acute oral, and inhalation. No effects are observed in 
    a skin irritation study, the eye irritation study shows it to be a 
    moderate irritant to the eyes; and results of the dermal sensitization 
    study shows it to be a non-sensitizer.
        2. Subchronic toxicity studies. i. A 28-day range-finding feeding 
    study conducted with cryolite in rats at dose levels of 0, 250, 500, 
    1,000, 2,000, 4,000, 10,000, 25,000 and 50,000 ppm in the diet 
    (representing approximately 0, 25, 50, 100, 200, 400, 1,000, 2,500 and 
    5,000 milligrams/kilograms/day) (mg/kg/day) with the only compound 
    related effect being a change in coloration and physical property of 
    the teeth.
        The NOEL was not determined. The LOEL is 250 ppm (25 mg/kg/day) 
    based on dental fluorosis.
        ii. A 90-day rat feeding study conducted with cryolite at dose 
    levels of 0, 50, 5,000, and 50,000 ppm (corresponding to 0, 3.8, 399.2 
    and 4172.3 mg/kg/day in males and 0, 4.5, 455.9 and 4758.1 mg/kg/day in 
    females).
        The NOEL is 50 ppm (3.8 mg/kg/day) for effects other than fluoride 
    accumulation. The LOEL is 5,000 ppm (399.2 mg/kg/day) based on lesions 
    observed in the stomach. Fluoride accumulated at all dose levels.
        iii. A 90-day dog feeding study conducted with cryolite at dose 
    levels of 0, 500, 10,000, and 50,000 ppm (corresponding to 0, 17, 368 
    and 1692 mg/kg/day).
        The NOEL is 10,000 ppm (368 mg/kg/day). The LOEL is 50,000 ppm 
    (1,692 mg/kg/day) for effects other than fluoride accumulation. 
    Fluoride accumulation occurred at all dose levels.
        3. Chronic/carcinogenicity studies.  i. A 2-year rat bioassay 
    conducted by the National Toxicology Program (NTP) using sodium 
    fluoride as the test material at dose levels of 0, 25, 100, and 175 
    ppm, in water, representing 0, 1.3, 5.2 and 8.6 mg/kg/day in males and 
    0, 1.3, 5.5 and 9.5 mg/kg/day in females.
        Osteosarcoma of the bone was only observed in one male in the 100 
    ppm group and in three males in the 175 ppm group. NTP considers this 
    to be equivocal evidence of carcinogenicity in male F344/N rats. The 
    NOEL is less than 25 ppm (1.3 mg/kg/day). The LOEL is 25 ppm (1.3 mg/
    kg/day) based on mottling of teeth, dentine incisor dysplasia, 
    increased serum, urine and bone fluoride levels in males and females 
    and incisor odontoblast and incisor ameloblast degeneration in males. 
    There was ``equivocal evidence'' of carcinogenic activity in male rats 
    and ``no evidence'' of carcinogenic activity in female rats.
        The NTP study utilizing sodium fluoride as the test material in 
    lieu of cryolite or synthetic cryolite satisfies the guideline study 
    requirement for both the rodent chronic feeding study and the rat 
    carcinogenicity study. Fluoride has been identified as the residue of 
    toxicological concern in cryolite and synthetic cryolite and the 
    available data show that these compounds act as free fluoride.
        ii. A 2-year mouse bioassay conducted by the NTP utilizing sodium 
    fluoride as the test material at dose levels of 0, 25, 100, and 175 
    ppm, in water, representing 0, 2.4, 9.6 and 16.7 mg/kg/day in males and 
    0, 2.8, 11.3 and 18.8 mg/kg/day in females.
        The NOEL is less than 25 ppm (2.4 mg/kg/day). The LOEL is 25 ppm 
    (2.4 mg/kg/day) based on attrition of the teeth in males, discoloration 
    and mottling of the teeth in males and females and increased bone 
    fluoride in both sexes. There was ``no evidence'' of carcinogenic 
    activity in male and female mice.
        This study utilizing sodium fluoride in lieu of cryolite or 
    synthetic cryolite as the test material satisfies the guideline study 
    requirement for a mouse carcinogenicity study for the reason described 
    above under item 3.i.
        iii. A 1-year chronic dog feeding study conducted with Cryolite at 
    dose levels of 0, 3,000, 10,000 and 30,000 ppm, representing 0, 95, 366 
    and 1,137 mg/kg/day in males and 0, 105, 387 and 1,139 mg/kg/day in 
    females (in terms of fluoride the doses are 0, 51, 198, and 614 mg F/
    kg/day for males and 0, 57, 209 and 615 mg F/kg/day for females).
        The NOEL (in terms of Cryolite) is less than 3,000 ppm (95 mg/kg/
    day in males and 105 mg/kg/day in females). The LOEL is 3,000 ppm (95 
    mg/kg/day) based on increases in emesis, nucleated cells in males, 
    renal lesions and a decrease in urine specific gravity in females.
        4. Other studies/documents. i. Mutagenicity studies including an 
    Ames test (negative) at dose levels of 167, 500, 1670, 5,000, 7,500 and 
    10,000 ug/plate; an in vitro assay in human lymphocytes (negative) at 
    100, 500, and 1,000 g/ml; and an unscheduled DNA synthesis 
    study in rat hepatocytes (negative) at dose levels up to and including 
    50 g/ml.
        ii. Drinking water Criteria Document on Fluoride. Fluoride has been 
    identified as the residue of toxicological concern in cryolite and 
    synthetic cryolite and the available data show that these compounds 
    which are approximately 52.8% fluoride, act as free fluoride.
        The EPA Office of Drinking Water issued a Drinking Water Criteria 
    Document on Fluoride (October 21, 1985) which presents summaries of 
    experimental and clinical data on the health effects of fluoride in 
    animals and humans. In general, the health effects of fluoride (F) 
    include dental fluorosis and skeletal fluorosis.
    
    B. Toxicological Endpoints
    
        1. Acute toxicity. Based on the available toxicity data, EPA has 
    determined that cryolite does not exhibit any adverse health effects 
    occurring as a result of a one day or single dietary or non-dietary 
    exposure.
        2. Short and intermediate-term toxicity. Based on the available 
    data, EPA has determined that cryolite does not exhibit any adverse 
    heath effects occurring as a result of short- or intermediate-term 
    dietary and non-dietary exposure.
    
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        3. Chronic toxicity. Rather than the establishment of the 
    traditional Reference Dose (RfD), a weight-of-the-evidence risk 
    assessment was determined by the Agency to be a more appropriate 
    approach for the assessment of the dietary exposure to fluoride 
    residues as a result of agricultural uses of cryolite for the following 
    reasons:
        i. National and international regulatory organizations (U.S. EPA 
    Office of Water, U.S. DHHS, the Canadian Government, and the World 
    Health Organization) have assessed potential health risks from exposure 
    to fluoride. The endpoints and estimated effect levels documented by 
    these organizations are similar.
        ii. The U.S. Surgeon General (Koop, 1984 and Elders, 1994) has 
    recommended a guideline level of exposure that should provide an 
    adequate ``margin of safety'' based on a large amount of human data, 
    including epidemiology studies.
        iii. Animal data considered in evaluating the proposed regulations 
    are consistent with human data with respect to dose related skeletal 
    effects.
        4.  Carcinogenicity.  Fluoride has been the subject of a 
    comprehensive review by the National Research Council (National Academy 
    of Sciences Subcommittee of Health Effects of Ingested Fluoride) who 
    concluded that ``... the available laboratory data are insufficient to 
    demonstrate a carcinogenic effect of fluoride in animals.'' and that 
    ``... the weight of evidence from more than 50 epidemiological studies 
    does not support the hypothesis of an association between fluoride 
    exposure and increased cancer risk in humans.'' EPA is in agreement 
    with the conclusions reached by the National Academy of Science (NAS).
        The available information does not support the regulation of 
    cryolite as a carcinogen and it has been classified as a Group D 
    chemical (not classifiable as to human carcinogenicity).
    
    C. Exposures and Risks
    
        1. From food and feed uses.  Tolerances have been established (40 
    CFR 180.145) for the residues of cryolite In or on a variety of raw 
    agricultural commodities. Risk assessments were conducted by EPA to 
    assess dietary exposures and risks from cryolite as follows:
        i. Acute exposure and risk. Based on the available acute toxicity 
    data, EPA has determined that cryolite does not pose any acute dietary 
    risk.
        ii. Chronic exposure and risk. The weight-of-the-evidence dietary 
    risk assessment was conducted utilizing the following factors. All 
    calculations are based on 2 L/day water consumption and 70 kg adult.
        a. There exists no directly applicable scientific documentation of 
    adverse medical effects at levels of fluoride below 8 mg/L 0.23 mg/kg/
    day. (U.S. EPA. 1985. National Primary Drinking Water Regulations; 
    Fluoride. Proposed Rulemaking. May 14, 1985, 50 FR 20166).
        b. Less than 0.4% of the U.S. population (on public water supplies) 
    is exposed to greater than 2 mg/L fluoride 0.057 mg/kg/day in the 
    public water supply. (U.S. EPA. 1985. drinking Water Criteria Document 
    on fluoride. U.S. EPA Office of Drinking Water, Washington, DC TR-832-
    5. pg. IV-3, Table IV-1.)
        The dietary exposure estimates used reassessed tolerances and 
    percent of crop treated. These exposure estimates are conservative 
    since average residues were not calculated and monitoring data were not 
    used to refine residue estimates.
        Section 408(b)(2)(F) allows the Agency to use data n the actual 
    percent of crop treated when establishing a tolerance only where the 
    Agency can make the following findings:
        (a) That data used are reliable and provided a valid basis for 
    showing the percentage of food derived from a crop that is likely 
    contain residues.
        (b) That the exposure estimate does not underestimate the exposure 
    for any significant subpopulation.
        (c) Where data on regional pesticide use and food consumption are 
    available, that the exposure estimate does not understate exposure for 
    any regional population. In addition, the Agency must provide for 
    periodic evaluation of any estimates used.
        Percent of crop treated estimates are derived from federal and 
    market survey data. EPA considers these data reliable. Typically a 
    range of estimates are supplied and the upper end of this range is used 
    for the exposure assessment. By using this upper end estimate of 
    percent crop treated, EPA is reasonably certain that exposure is not 
    underestimated for any significant subpopulation. Further, regional 
    consumption information is taken into account through EPA's computer-
    based model for evaluating the exposure of significant subpopulations 
    including several regional groups. Review of this regional data allows 
    EPA to be reasonably certain that no regional population is exposed to 
    residue levels higher than those estimated by EPA. EPA has made these 
    findings when appropriate with respect to the proposed tolerance. EPA 
    has not provided for periodic reevaluation of the data on percent crop 
    treated because this tolerance has a time-limitation.
        2. From drinking water-- i. Acute exposure and risk. Based on the 
    available acute toxicity data, EPA has determined that fluoride does 
    not pose any acute dietary risk.
        ii. Chronic exposure and risk. Fluoride levels in public drinking 
    water are regulated under the Safe Drinking Water Act. EPA has 
    established a Maximum Concentration Limit (MCL) at 4.0 mg/L 0.114 mg/
    kg/day to protect against crippling skeletal fluorosis (April 2, 1986) 
    (51 FR 11396). The MCL established on April 2, 1986 finalizes interim 
    regulations set in the Federal Register of November 14, 1985 (50 FR 
    47142), and proposed in the Federal Register of May 14, 1985 (50 FR 
    20164). In addition, these Federal Register notices established a 
    Secondary Maximum Contaminant Level (SMCL) at 2.0 mg/L 0.057 mg/kg/day 
    for cosmetic effects (objectionable dental fluorosis) which are not 
    considered to be adverse health effects by the Surgeon General.
        As described above, less than 0.4% of the U.S. population (on 
    public water supplies) is exposed to greater than 2 mg/L fluoride 0.057 
    mg/kg/day in the public water supply.
        3. From non-dietary exposure.  Cryolite is registered for use on 
    ornamentals, a use which could result in residential, non-occupational 
    exposure. It is not registered for indoor use. EPA has not estimated 
    non-dietary or residential exposure from registered ornamental uses of 
    cryolite because
        i. There are no toxicological endpoints identified for cryolite.
        ii. Fluoride occurs naturally in the environmental background and 
    there would not be significant exposure to fluoride from the use of 
    cryolite.
        iii. It would not be appropriate since the available information 
    regarding solubility and degradation indicates that there would likely 
    be no appreciable dermal absorption. The Agency does not anticipate 
    significant non-dietary exposure from the use of cryolite.
        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.'' The Agency believes that ``available 
    information'' in this context might include not only toxicity, 
    chemistry, and exposure data, but also scientific policies and 
    methodologies for understanding common mechanisms of
    
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    toxicity and conducting cumulative risk assessments. For most 
    pesticides, although the Agency has some information in its files that 
    may turn out to be helpful in eventually determining whether a 
    pesticide shares a common mechanism of toxicity with any other 
    substances, EPA does not at this time have the methodologies to resolve 
    the complex scientific issues concerning common mechanism of toxicity 
    in a meaningful way. EPA has begun a pilot process to study this issue 
    further through the examination of particular classes of pesticides. 
    The Agency hopes that the results of this pilot process will increase 
    the Agency's scientific understanding of this question such that EPA 
    will be able to develop and apply scientific principles for better 
    determining which chemicals have a common mechanism of toxicity and 
    evaluating the cumulative effects of such chemicals. The Agency 
    anticipates, however, that even as its understanding of the science of 
    common mechanisms increases, decisions on specific classes of chemicals 
    will be heavily dependent on chemical specific data, much of which may 
    not be presently available.
        Although at present the Agency does not know how to apply the 
    information in its files concerning common mechanism issues to most 
    risk assessments, there are pesticides as to which the common mechanism 
    issues can be resolved. These pesticides include pesticides that are 
    toxicologically dissimilar to existing chemical substances (in which 
    case the Agency can conclude that it is unlikely that a pesticide 
    shares a common mechanism of activity with other substances) and 
    pesticides that produce a common toxic metabolite (in which case common 
    mechanism of activity will be assumed).
        EPA does not have, at this time, available data to determine 
    whether cryolite 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, 
    cryolite 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 cryolite has a common mechanism of toxicity 
    with other substances. For the purpose of this time-limited tolerance, 
    the Agency has considered risks from cryolite and from fluoride in 
    intentionally fluoridated water.
    
    D. Aggregate Risks and Determination of Safety for U.S. Population
    
        1. Acute risk.  Based on the available acute toxicity data, EPA has 
    determined that cryolite does not pose any acute dietary risk.
        2. Chronic risk.  Fluoride is ubiquitous and may be present at low 
    levels in air, soils and in foodstuffs that have not been treated with 
    cryolite and/or synthetic cryolite as well as in drinking water. The 
    atmospheric levels of fluoride and incidental dietary exposures to 
    fluoride as a toothpaste additive or as a dental treatment contribute 
    relatively little to the average level of dietary fluoride exposure and 
    are not further considered in the exposure estimate.
        Dietary exposure estimates using reassessed tolerance/including the 
    subject tolerance for potatoes ( which is estimated as approximately 
    0.00016 mg/kg/day) and percent of crops treated are approximately 0.020 
    mg/kg/day for the U.S. population and 0.028 mg/kg/day for the highest 
    exposed subgroup (females 13 years old and over, nursing). These 
    exposure estimates are conservative since average residues were not 
    calculated and monitoring data were not used to refine residue 
    estimates.
        Therefore, it can be concluded that levels of fluoride in/on food 
    from the agricultural use of Cryolite plus fluoride levels in U.S. 
    drinking water supplies (0.057 mg/kg/day) results in a high-end daily 
    dietary intake of fluoride of approximately 0.085 mg/kg/day. This is 
    less than the Maximum Concentration Limit (MCL) of 4.0 mg/L 0.114 mg/
    kg/day, a level which provides no known or anticipated adverse health 
    effect as determined by the Surgeon General.
        Due to the fact that fluoride naturally occurs at low levels in 
    food and air as well as drinking water, there is a low percentage of 
    the population (0.4%) exposed to levels above the secondary Maximum 
    Contaminant Level (2 mg/L) and below the MCL, dietary exposure from 
    agricultural uses is low (typically much less than ca. 66% of the 
    levels found in intentionally fluoridated water), and aggregate high-
    end exposure is estimated to be below the MCL, EPA concludes there is a 
    reasonable certainty that no harm will result from aggregate exposure 
    to fluoride residues.
        3. Short-and intermediate -term risk.  Short-and intermediate-term 
    risk aggregate exposure takes into account chronic dietary food and 
    water (considered to be a background exposure level) plus indoor and 
    outdoor residential exposure. As explained above, EPA does not 
    anticipate significant non-dietary (residential) exposure from the use 
    of cryolite.
    
    E. Aggregate Cancer Risk for U.S. Population
    
        As described above, the available information does not support the 
    regulation of cryolite as a carcinogen and it has been classified as a 
    Group D chemical (not classifiable as to human carcinogenicity).
    
    F. Aggregate Risks and Determination of Safety for Infants and Children
    
        1. Safety factor for infants and children-- i. In general.  In 
    assessing the potential for additional sensitivity of infants and 
    children to residues of cryolite, EPA considered data from oral 
    developmental toxicity studies in the rat and mouse; and a range-
    finding study in the rabbit as well as data from a 2-generation 
    reproduction study in the rat. The developmental toxicity studies are 
    designed to evaluate adverse effects on the developing organism 
    resulting from pesticide exposure during prenatal development to one or 
    both parents. 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 post-natal 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 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 MOE and 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.
        ii. Developmental toxicity studies.  A developmental toxicity study 
    conducted with cryolite in rats at dose levels of 0, 750, 1,500, and 
    3,000 mg/kg/day (gavage) in which the NOEL for both developmental and 
    maternal toxicity was 3,000 mg/kg/day. At this dose level, the only 
    observation was whitening of the teeth of dams.
    
    [[Page 64299]]
    
        A developmental toxicity study conducted in female mice with 
    Cryolite at dose levels of 0, 30, 100 and 300 mg/kg/day (gavage) in 
    which the NOEL for maternal toxicity was 30 mg/kg/day and the LOEL was 
    100 mg/kg/day based on the occurrence of dark red contents of the 
    stomach. Fetuses at the highest dose tested, 300 mg/kg/day exhibited 
    bent ribs and bent limb bones.
        A range-finding developmental toxicity study conducted in female 
    rabbits with Cryolite at dose levels of 0, 10, 30, 100, 300 and 1,000 
    mg/kg/day (gavage) which showed only severe maternal effects at all 
    doses. There were no developmental findings in the fetuses up to 30 mg/
    kg/day. At doses greater than 30 mg/kg/day, developmental findings were 
    not observed due to the severe maternal toxicity.
        A new rabbit developmental study is not required at this time since 
    there are two acceptable rodent developmental studies (rat and mouse) 
    showing no specific adverse developmental effects. In addition, the 
    National Academy of Sciences (NAS) report supports this decision. It is 
    unlikely that an additional rabbit developmental study would alter the 
    risk evaluation for cryolite.
        The rabbit range-finding study suggested that severe maternal 
    toxicity occurred at lower doses than external developmental toxicity. 
    However, following an extensive literature evaluation, the National 
    Research Council (National Academy of Sciences Subcommittee of Health 
    Effects of Ingested Fluoride) (NAS) determined that:
        There have been reports of adverse effects on reproductive 
    outcomes associated with high levels of fluoride intake in many 
    animal species. In most of the studies, however, the fluoride 
    concentrations associated with adverse effects were far higher than 
    those encountered in drinking water. ...
        Based on these findings, the subcommittee concludes that the 
    fluoride concentrations associated with adverse reproductive effects 
    in animals are far higher than those to which human populations are 
    exposed. Consequently, ingestion of fluoride at current 
    concentrations should have no adverse effects on human reproduction.
    
        iii. Reproductive toxicity study.  A 2-generation reproduction 
    study conducted with Cryolite in the diet of rats at dose levels of 0, 
    200, 600, and 1,800 ppm (representing 0, 14, 42, and 128 mg/kg/day for 
    males and 0, 16, 49, and 149 mg/kg/day for females, respectively, 
    during premating) in which the LOEL for systemic toxicity was 200 ppm 
    (15 mg/kg/day) based on dental fluorosis. The NOEL for decreased pup 
    body weight was 46 mg/kg/day and, at the lowest dose tested (8 mg/kg/
    day) there was parental toxicity. Therefore, there was pup toxicity 
    only in the presence of parental toxicity.
        iv. Pre- and post-natal sensitivity.  Based on current data 
    requirements, the database relative to pre- and post-natal toxicity is 
    complete. These data taken together suggest minimal concern for 
    developmental or reproductive toxicity and do not indicate any 
    increased pre- or post-natal sensitivity.
        v. Conclusion.  Therefore, EPA concludes that reliable data support 
    use of the weight-of-the-evidence risk assessment approach for the 
    assessment of risks to infants and children associated with the use of 
    cryolite and that an additional safety factor is not needed.
        2. Acute risk.  As described above, based on available acute 
    toxicity data, EPA has determined that cryolite does not pose any acute 
    dietary risk.
        3. Chronic risk.  The high end dietary exposure estimate for 
    infants and children using reassessed tolerances and percent of crops 
    treated is 0.024 mg/kg/day. This is lower than the exposure estimate of 
    0.028 mg/kg/day which was used in the Agency's determination of safety 
    for the U.S. population described above.
        EPA concludes that there is a reasonable certainty that no harm 
    will result to infants and children from aggregate exposure to fluoride 
    residues.
        4. Short- or intermediate- term risk.  As described above, EPA has 
    determined that cryolite does not exhibit any adverse health effects 
    occurring as a result of short- or intermediate-term dietary and non-
    dietary exposure.
    
    III. Other Considerations
    
    A. Metabolism In Plants and Animals
    
        The metabolism of the subject insecticides in plants and animals is 
    adequately understood.
        Open literature studies show that human and animal metabolism of 
    cryolite and/or synthetic cryolite manifests itself as normal free 
    fluoride metabolism. That is, dissociation occurs, producing free 
    fluoride ions which are assimilated into bone. The residue of concern 
    in animals is total fluoride.
        Plant residues are inorganic surface residues of cryolite which are 
    measured as total fluoride. Uptake and translocation of cryolite 
    residues from soil is unlikely due to the low water solubility of 
    cryolite.
    
    B. Analytical Enforcement Methodology
    
        An adequate analytical method (fluoride specific electrode) is 
    available for enforcement purposes for plant and animal residues. The 
    limit of quantitation is 0.05 ppm. Because cryolite is an inorganic 
    ionic compound, the requirement for data using the multi-residue 
    protocols in the Pesticide Analytical Manual (PAM) Vol. I is not 
    applicable.
        Because of the long lead time from establishing these tolerances, 
    to publication of the enforcement methodology in the PAM Vol. II, the 
    analytical methodology is being made available in the interim to anyone 
    interested in pesticide enforcement when requested from; Calvin Furlow, 
    Public Information Branch, Field Operations Division (H7506C), Office 
    of Pesticide Programs, Environmental Protection Agency, 401 M St., 
    SW.,Washington, DC 20460. Office location and telephone number; Rm. 
    1128, CM #2, 1921 Jefferson Davis Hwy., VA 22202, (703)-305-5232.
    
    C. Magnitude of Residues
    
        It has been determined that residues of cryolite are not expected 
    to exceed 2.0 ppm in potatoes and 22.0 ppm in processed potato waste.
        Data submitted in support of the subject petition show background 
    levels of fluoride in untreated potatoes ranged from 0.14 ppm to 0.31 
    ppm and are consistent with the ranges reported in the open literature. 
    Levels of fluoride found in the treated potatoes ranged from 0.18 ppm 
    to 0.94 ppm. The residue analytical method used for enforcing the 
    subject tolerance and regulation cannot distinguish between the 
    naturally occurring fluoride and the fluoride resulting from use of 
    cryolite and/or synthetic cryolite.
        A potato processing study showed that cryolite residues did not 
    concentrate in potato chips, flakes or granules. Therefore, tolerances 
    on these commodities are not required.
        There is no reasonable expectation of finite fluoride residues in 
    ruminant or poultry tissues as a result of livestock ingestion of 
    cryolite and this situation falls under 40 CFR 180.6 (a)(3). Therefore, 
    tolerances for cryolite residues in meat, milk, poultry, and eggs are 
    not required.
    
    D. International Residue Limits
    
        No Codex Maximum Residue Limits (MRLs) for fluorine compounds 
    (cryolite) exist. Therefore, there are no questions of compatibility 
    with respect to Codex MRLs and U. S. tolerances.
    
    E. Rotational Crop Restrictions
    
        The residue available to rotational crops is expected to be 
    negligible with
    
    [[Page 64300]]
    
    respect to the amount of free fluorine occurring naturally in soil.
    
    F. Endocrine Effects
    
        No evidence of such effects were reported in the toxicology studies 
    described above. There is no evidence at this time that cryolite causes 
    endocrine effects.
    
    IV. Conclusion
    
        Therefore, the tolerance is established for residues of cryolite in 
    or on potatoes at 2.0 ppm and in potato waste from processing at 22.0 
    ppm.
    
    V. Objections and Hearing Requests
    
        The new FFDCA section 408(g) provides essentially the same process 
    for persons to ``object'' to a tolerance regulation issued by EPA under 
    new section 408(e) and (l)(6) as was provided in the old section 408 
    and in section 409. However, the period for filing objections is 60 
    days, rather than 30 days. EPA currently has procedural regulations 
    which govern the submission of objections and hearing requests. These 
    regulations will require some modification to reflect the new law. 
    However, until those modifications can be made, EPA will continue to 
    use those procedural regulations with appropriate adjustments to 
    reflect the new law.
        Any person may, by February 3, 1998, file written objections to any 
    aspect of this regulation and may also request a hearing on those 
    objections. Objections and hearing requests must be filed with the 
    Hearing Clerk, at the address given above (40 CFR 178.20). A copy of 
    the objections and/or hearing requests filed with the Hearing Clerk 
    should be submitted to the OPP docket for this rulemaking. The 
    objections submitted must specify the provisions of the regulation 
    deemed objectionable and the grounds for the objections (40 CFR 
    178.25). Each objection must be accompanied by the fee prescribed by 40 
    CFR 180.33(i). If a hearing is requested, the objections must include a 
    statement of the factual issues on which a hearing is requested, the 
    requestor's contentions on such issues, and a summary of any evidence 
    relied upon by the requestor (40 CFR 178.27). A request for a hearing 
    will be granted if the Administrator determines that the material 
    submitted shows the following: There is 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 in the manner sought by the requestor would be adequate 
    to justify the action requested (40 CFR 178.32). 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.
    
    VI. Public Docket
    
        A record has been established for this rulemaking under docket 
    control number [OPP-300586] (including any comments and data submitted 
    electronically). A public version of this record, including printed, 
    paper versions of electronic comments, which does not include any 
    information claimed as CBI, is available for inspection from 8:30 a.m. 
    to 4 p.m., Monday through Friday, excluding legal holidays. The public 
    record is located in Room 1132 of the Public Information and Records 
    Integrity Branch, Information Resources and Services Division (7502C), 
    Office of Pesticide Programs, Environmental Protection Agency, Crystal 
    Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA.
        The official record for this rulemaking, as well as the public 
    version, as described above will be kept in paper form. Accordingly, 
    EPA will transfer any copies of objections and hearing requests 
    received electronically into printed, paper form as they are received 
    and will place the paper copies in the official rulemaking record which 
    will also include all comments submitted directly in writing. The 
    official rulemaking record is the paper record maintained at the 
    Virginia address in ``ADDRESSES'' at the beginning of this document.
    
    VII. Regulatory Assessment Requirements
    
        This final rule establishes a tolerance under FFDCA section 408(d) 
    in response to a petition submitted to the Agency. The Office of 
    Management and Budget (OMB) has exempted these types of actions from 
    review under Executive Order 12866, entitled Regulatory Planning and 
    Review (58 FR 51735, October 4, 1993). 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) (Pub. L. 104-4). Nor does 
    it require any prior consultation as specified by Executive Order 
    12875, entitled Enhancing the Intergovernmental Partnership (58 FR 
    58093, October 28, 1993), or special considerations as required by 
    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).
        In addition, since these tolerances and exemptions that are 
    established on the basis of a petition under FFDCA section 408(d), such 
    as the tolerance in this final rule, do not require the issuance of a 
    proposed rule, the requirements of the Regulatory Flexibility Act (RFA) 
    (5 U.S.C. 601 et seq.) do not apply. Nevertheless, the Agency has 
    previously assessed whether establishing tolerances, exemptions from 
    tolerances, raising tolerance levels or expanding exemptions might 
    adversely impact small entities and concluded, as a generic matter, 
    that there is no adverse economic impact. The factual basis for the 
    Agency's generic certification for tolerance actions published on May 
    4, 1981 (46 FR 24950) and was provided to the Chief Counsel for 
    Advocacy of the Small Business Administration.
    
    VIII. Submission to Congress and the General Accounting Office
    
        Under 5 U.S.C. 801(a)(1)(A), as added by the Small Business 
    Regulatory Enforcement Fairness Act of 1996, the Agency has submitted 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 General Accounting Office prior to publication of this rule in 
    today's Federal Register. This 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: November 21, 1997.
    Linda A. Travers,
    Acting Director, Office of Pesticide Programs.
        Therefore, 40 CFR chapter I is amended as follows:
    
    [[Page 64301]]
    
    PART 180--[AMENDED]
    
        a. The authority citation for part 180 continues to read as 
    follows:
    
        Authority : 21 U.S.C. 346a and 371.
    
        b. In Sec. 180.145:
        i. By designating paragraph (a) as paragraph (a)(1), by adding 
    paragraph (a)(2), and by adding a heading to paragraph (a).
        ii. By removing paragraph (c) and redesignating paragraph (b) as 
    new paragraph (c) and adding a heading.
        iii. By adding and reserving new paragraphs (b) and (d) with 
    headings.
        The amendments to Sec. 180.145 read as follows:
    
    
    Sec. 180.145  Fluorine compounds: tolerances for residues.
    
        (a) General. *        *        *
        (2) Time-limited tolerances are established for residues of the 
    insecticidal fluorine compounds cryolite and synthetic cryolite (sodium 
    aluminum fluoride) in or on the commodities as follows:
    
                                                                                                                                                            
    --------------------------------------------------------------------------------------------------------------------------------------------------------
                             Commodity                                        Parts per million                          Expiration/revocation date         
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    Potatoes..................................................                                            2.0                                     11/21/2001
    Potatoes, waste from processing...........................                                           22.0                                     11/21/2001
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    
        (b) Section 18 emergency exemptions. [Reserved]
        (c) Tolerances with regional registrations. *        *        *
        (d) Indirect or inadvertent residues. [Reserved]
    
    [FR Doc. 97-31920 Filed 12-4-97; 8:45 am]
    BILLING CODE 6560-50F
    
    
    

Document Information

Effective Date:
12/5/1997
Published:
12/05/1997
Department:
Environmental Protection Agency
Entry Type:
Rule
Action:
Final rule.
Document Number:
97-31920
Dates:
This regulation is effective December 5, 1997. Objections and requests for hearings must be received by EPA on or before February 3, 1998.
Pages:
64294-64301 (8 pages)
Docket Numbers:
OPP-300586, FRL-5756-5
RINs:
2070-AB78
PDF File:
97-31920.pdf
CFR: (1)
40 CFR 180.145