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

[Federal Register: August 23, 2006 (Volume 71, Number 163)]

[Rules and Regulations]

[Page 49358-49363]

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

[DOCID:fr23au06-16]

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2005-0540; FRL-8086-9]

Azoxystrobin; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

SUMMARY: This regulation establishes tolerances for combined residues of azoxystrobin in or on vegetables, foliage of legume, group 7; vegetables, fruiting, group 8 (except tomato); pea and bean, succulent shelled, subgroup 6B; pea and bean, dried shelled, except soybean subgroup, 6C; citrus, dried pulp; citrus, oil; and fruit, citrus, Group 10. Interregional Research Project Number 4 (IR-4) requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of 1996 (FQPA). EPA is also deleting several existing tolerances that are no longer needed as a result of this action.

DATES: This regulation is effective August 23, 2006. Objections and requests for hearings must be received on or before October 23, 2006, and must be filed in accordance with the instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).

ADDRESSES: EPA has established a docket for this action under docket identification (ID) number EPA-HQ-OPP-2005-0540. All documents in the docket are listed in the index for the docket. Although listed in the index, some information is not publicly available, e.g., Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available in the electronic docket at http://www.regulations.gov, or,

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

FOR FURTHER INFORMATION CONTACT: Barbara Madden, Registration Division (7505P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone number: (703) 305-6463; e-mail address: madden.barbara@epa.gov.

SUPPLEMENTARY INFORMATION:

  1. General Information

    1. Does this Action Apply to Me?

      You may be potentially affected by this action if you are an agricultural producer, food manufacturer, or pesticide manufacturer. Potentially affected entities may include, but are not limited to:

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

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

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

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

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

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

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

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

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

      [fxsp0] ecfr. To access the OPPTS Harmonized

      Guidelines referenced in this document, go directly

      [[Page 49359]]

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

    3. Can I File an Objection or Hearing Request?

      Under section 408(g) of the FFDCA, as amended by the FQPA, any person may file an objection to any aspect of this regulation and may also request a hearing on those objections. The EPA procedural regulations which govern the submission of objections and requests for hearings appear in 40 CFR part 178. You must file your objection or request a hearing on this regulation in accordance with the instructions provided in 40 CFR part 178. To ensure proper receipt by EPA, you must identify docket ID number EPA-HQ-OPP-2005-0540 in the subject line on the first page of your submission. All requests must be in writing, and must be mailed or delivered to the Hearing Clerk on or before October 23, 2006.

      In addition to filing an objection or hearing request with the Hearing Clerk as described in 40 CFR part 178, please submit a copy of the filing that does not contain any CBI for inclusion in the public docket that is described in ADDRESSES. Information not marked confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA without prior notice. Submit your copies, identified by docket ID number EPA-HQ-OPP-2005-0540 by one of the following methods:

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

      Follow the on-line instructions for submitting comments.

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

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

  2. Background and Statutory Findings

    In the Federal Register of March 8, 2006 (71 FR 11624) (FRL-7765- 5), EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C. 346a(d)(3), announcing the filing of a pesticide petition (PP 5E6916) by Interregional Research Project 4 (IR-4), 681 US Highway 1 South, North Brunswick, NJ 08902-3390. The petition requested that 40 CFR 180.507 be amended by establishing a tolerance for combined residues of the fungicide of azoxystrobin, [methyl (E)-2-(2-(6-(2- cyanophenoxy)pyrimidin-4-yloxy)phenyl)-3-methoxyacrylate] and the Z isomer of azoxystrobin, [methyl (Z)-2-(2-(6-(2-cyanophenoxy)pyrimidin- 4-yloxy)phenyl)-3-methoxyacrylate], in or on citrus, dried pulp at 20.0 parts per million (ppm); citrus, oil at 40.0 ppm; fruit, citrus, group 10 at 10.0 ppm; vegetable, foliage of legume, group 7 at 30.0 ppm; vegetable, fruiting, group 8, except tomato at 2.0 ppm; pea and bean, succulent shelled, subgroup 6B at 0.5 ppm; pea and bean, dried shelled, except soybean, subgroup 6C at 0.5 ppm; animal feed, nongrass, group 18, forage at 30.0 ppm; animal feed, nongrass, group 18 hay at 55.0 ppm. That notice included a summary of the petition prepared by Syngenta, the registrant on behalf of the Interregional Research Project Number 4 (IR-4). One comment was received on the notice of filing. EPA's response to this comment is discussed in Unit IV.C.

    EPA is also deleting several established tolerances in Sec. 180.507(a)(1) and (a)(3) that are no longer needed. The revisions to Sec. 180.507(a)(1) are as follows:

    i. Delete eggplant and pepper tolerances at 2.0 ppm. Replaced with vegetable, fruiting group 8 (except tomato) at 2.0 ppm.

    ii. Delete soybean, forage at 25.0. Replaced with vegetable, foliage of legume, group 7 at 30.0 ppm.

    The revision to paragraph (a)(3) is to delete the time-limited tolerance for potato at 0.03 ppm because it has expired and remove it from Sec. 180.507.

    Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a tolerance (the legal limit for a pesticide chemical residue in or on a food) only if EPA determines that the tolerance is ``safe.'' Section 408(b)(2)(A)(ii) of FFDCA defines ``safe'' to mean that ``there is a reasonable certainty that no harm will result from aggregate exposure to the pesticide chemical residue, including all anticipated dietary exposures and all other exposures for which there is reliable information.'' This includes exposure through drinking water and in residential settings, but does not include occupational exposure. Section 408(b)(2)(C) of FFDCA requires EPA to give special consideration to exposure of infants and children to the pesticide chemical residue in establishing a tolerance and to ``ensure that there is a reasonable certainty that no harm will result to infants and children from aggregate exposure to the pesticide chemical residue....''

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

  3. Aggregate Risk Assessment and Determination of Safety

    Consistent with section 408(b)(2)(D) of FFDCA, EPA has reviewed the available scientific data and other relevant information in support of this action. EPA has sufficient data to assess the hazards of and to make a determination on aggregate exposure, consistent with section 408(b)(2) of FFDCA, for a tolerance for combined residues of azoxystrobin, [methyl (E)-2-(2-(6-(2-cyanophenoxy)pyrimidin-4- yloxy)phenyl)-3-methoxyacrylate] and the Z isomer of azoxystrobin,

    [methyl (Z)-2-(2-(6-(2-cyanophenoxy)pyrimidin-4-yloxy)phenyl)-3- methoxyacrylate] on citrus, dried pulp at 20.0 ppm; citrus, oil at 40.0 ppm; fruit, citrus, group 10 at 10.0 ppm; vegetable, foliage of legume, group 7 at 30.0 ppm; vegetable, fruiting, group 8, except tomato at 2.0 ppm; pea and bean, succulent shelled, subgroup 6B at 0.5 ppm; and pea and bean, dried shelled, except soybean, subgroup 6C at 0.5 ppm. EPA's assessment of exposures and risks associated with establishing the tolerance follows.

    1. Toxicological Profile

      EPA has evaluated the available toxicity data and considered 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. Specific information on the studies received and the nature of the toxic effects caused by azoxystrobin as well as the no-observed- adverse-effect-level (NOAEL) and the lowest-observed-adverse-effect- level (LOAEL) from the toxicity studies can be found at http://www.epa.gov/fedrgstr/EPA-PEST/2000/September/Day-29/p25051.htm .

    2. Toxicological Endpoints

      For hazards that have a threshold below which there is no appreciable risk, the dose at which no adverse effects are observed (the NOAEL) from the toxicology study identified as appropriate for use in risk assessment is used to estimate the toxicological level

      [[Page 49360]]

      of concern (LOC). However, the lowest dose at which adverse effects of concern are identified (the LOAEL) is sometimes used for risk assessment if no NOAEL was achieved in the toxicology study selected. An uncertainty factor (UF) is applied to reflect uncertainties inherent in the extrapolation from laboratory animal data to humans and in the variations in sensitivity among members of the human population as well as other unknowns.

      The linear default risk methodology (Q*) is the primary method currently used by the Agency to quantify non-threshold hazards such as cancer. The Q* approach assumes that any amount of exposure will lead to some degree of cancer risk, estimates risk in terms of the probability of occurrence of additional cancer cases. More information can be found on the general principles EPA uses in risk characterization at http://www.epa.gov/pesticides/health/human.htm.

      A summary of the toxicological endpoints for azoxystrobin used for human risk assessment is discussed in Unit III.B. of the final rule published in the Federal Register of September 29, 2000 (65 FR 58404) (FRL-6749-1).

    3. Exposure Assessment

      1. Dietary exposure from food and feed uses. Tolerances have been established (40 CFR 180.507) for the combined residues of azoxystrobin,

        [methyl (E)-2-(2-(6-(2-cyanophenoxy)pyrimidin-4-yloxy)phenyl)-3- methoxyacrylate] and the Z isomer of azoxystrobin, [methyl (Z)-2-(2-(6- (2-cyanophenoxy)pyrimidin-4-yloxy)phenyl)-3-methoxyacrylate], in or on a variety of raw agricultural commodities. In addition, tolerances for livestock commodities have been established for the residues of azoxystrobin [methyl(E)-2-(2-(6-(2-cyanophenoxy)pyrimidin-4- yloxy)phenyl)-3-methoxyacrylate] in or on milk; meat, fat, and meat byproducts (mbyp) of cattle, goat, hog, horse, and sheep. Risk assessments were conducted by EPA to assess dietary exposures from azoxystrobin in food as follows:

        i. Acute exposure. Quantitative acute dietary exposure and risk assessments are performed for a food-use pesticide, if a toxicological study has indicated the possibility of an effect of concern occurring as a result of a one-day or single exposure. In conducting the acute dietary exposure assessment EPA used the Dietary Exposure Evaluation Model software with the Food Commodity Intake Database (DEEM-FCID\TM\), which incorporates food consumption data as reported by respondents in the USDA 1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by Individuals (CSFII), and accumulated exposure to the chemical for each commodity. The following assumptions were made for the acute exposure assessments: One hundred percent of proposed and registered crops are assumed treated with azoxystrobin and tolerance-level residues.

        ii. Chronic exposure. In conducting the chronic dietary exposure assessment EPA used the Dietary Exposure Evaluation Model software with the Food Commodity Intake Database (DEEM-FCID\TM\), which incorporates food consumption data as reported by respondents in the USDA 1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by Individuals (CSFII), and accumulated exposure to the chemical for each commodity. The following assumptions were made for the chronic exposure assessments: Some percent crop treated information for selected crops and tolerance-level residues.

        iii. Cancer. Azoxystrobin is classified as ``not likely to be a human carcinogen.'' Therefore, a cancer dietary exposure assessment was not performed.

        iv. Anticipated residue and percent crop treated (PCT) information. Section 408(b)(2)(F) of FFDCA states that the Agency may use data on the actual percent of food treated for assessing chronic dietary risk only if the Agency can make the following findings: Condition 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; Condition 2, that the exposure estimate does not underestimate exposure for any significant subpopulation group; and Condition 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 PCT as required by section 408(b)(2)(F) of FFDCA, EPA may require registrants to submit data on PCT.

        The Agency used PCT information as follows: almond, 20%; apricot, 15%; asparagus, 1%; dry beans and peas, 1%; green beans, 25%; garden beets, 15%; sugar beets, 1%; blueberry, 15%; cabbage, 5%; cantaloupes, 10%; carrot, 10%; celery, 10%; cherry, 5%; sweet corn, 10%; cucumber, 15%; filbert, 5%; garlic, 50%; grape, 10%; grapefruit, 20%; guar, 1%; honeydew melon, 5%; lettuce, 1%; mustard greens, 15%; onion, 10%; orange, 17%; parsley, 30%; peach, 5%; peanut, 10%; pecan, 1%; pepper, 10%; pistachio, 30%; prunes and plum, 1%; potato, 25%; pumpkin, 20%; rapeseed (canola), 5%; rice, 25%; safflower, 5%; soybean, 1%; spinach, 10%; summer and winter squash, 15%; strawberry, 20%; sunflower, 5%; tangerine, 20%; tomato, 20%; turnip greens, 15%; walnut, 1%; watermelon, 25%; and wheat, 1%. EPA estimates projected percent crop treated (PPCT) for a new pesticide use by assuming that the percent crop treated (PCT) during the pesticide's initial five years of use on a specific use site will not exceed the average PCT of the dominant pesticide (i.e., the one with the greatest PCT) on that site over the three most recent surveys. Comparisons are only made among pesticides of the same pesticide types (i.e., the dominant fungicide on the use site is selected for comparison with a new fungicide). The PCTs included in the average may be each for the same pesticide or for different pesticides since the same or different pesticides may dominate for each year selected. Typically, EPA uses USDA/NASS as the source for raw PCT data because it is publicly available and does not have to be calculated from available data sources. When a specific use site is not surveyed by USDA/NASS, EPA uses proprietary data and calculates the estimated PCT. The estimated PPCT for azoxystrobin on PH oranges is based on the recent PCT of market leader imazilil. The estimated PPCT for this new use of azoxystrobin is a high-end estimate that is highly unlikely to be exceeded during the initial five years of actual use. This is based on the fact that azoxystrobin complements imazilil in fungicide resistance programs to control imazilil-resistant populations of Penicillium spp. (green mold disease) and to reduce the potential for crop losses from fungicide-resistant populations of the pathogen. Azoxystrobin is highly unlikely to exceed imazilil use because it is used in imazilil resistance management. Thus the given PPCT for azoxystrobin is appropriate for use in chronic dietary risk assessment.

      2. Dietary exposure from drinking water. The Agency lacks sufficient monitoring exposure data to complete a comprehensive dietary exposure analysis and risk assessment for azoxystrobin in drinking water. Because the Agency does not have comprehensive monitoring data, drinking water concentration estimates are made by reliance on simulation or modeling taking into account data on

        [[Page 49361]]

        the physical characteristics of azoxystrobin. Further information regarding EPA drinking water models used in pesticide exposure assessment can be found at http://www.epa.gov/oppefed1/models/water/index.htm .

        Based on the FIRST and SCI-GROW models, the estimated environmental concentrations (EECs) of azoxystrobin for chronic exposures are estimated to be 33 parts per billion (ppb) for surface water and 3.1 ppb for ground water.The estimated drinking water concentrations (EDWCs) for azoxystrobin were calculated based on a maximum application rate for turf of 0.55 lb ai/A/application with 9 applications per year. Modeled estimates of drinking water concentrations were directly entered into the dietary exposure model (DEEM-FCID). For chronic dietary risk assessment, the annual average concentration of 33 ppb was used to access the contribution to drinking water.

      3. From non-dietary exposure. The term ``residential exposure'' is used in this document to refer to non-occupational, non-dietary exposure (e.g., for lawn and garden pest control, indoor pest control, termiticides, and flea and tick control on pets).

        Azoxystrobin is currently registered for use on the following residential non-dietary sites: Residential turfgrass and ornamentals, as well as indoor surfaces. The risk assessment was conducted using the following residential exposure assumptions: Residential handlers may receive short-term dermal and inhalation exposure to azoxystrobin when mixing, loading and applying the formulations. Adults and children may be exposed to azoxystrobin residues from dermal contact with foliage/surfaces during postapplication activities. Toddlers may receive short- and intermediate-term oral exposure from incidental ingestion during postapplication activities.

        Inhalation daily doses for residential handlers were calculated for the WDG formulation using data for mixing, loading and applying a liquid. Based on PHED unit exposure values from other handler scenarios with these formulation types, the exposure from a WDG is expected to be less than that of handling a liquid. The open mixing, loading, and applying liquid using a low pressure handwand (PHED) handler scenario was evaluated. The residential exposure and risk assessment for turf and ornamentals was conducted using the application rate for turf because it is the highest use rate.

        Exposures were estimated for residential handler activities including: Mix, load and spot application of liquid formulation (low- pressure hand sprayer), and mix, load and broadcast application of liquid formulation (garden hose-end sprayer). In addition, short-term exposures were estimated for infants and children for postapplication exposure scenarios resulting from indoor surface treatment including: Toddlers' incidental ingestion of pesticide residues on hard indoor surfaces from hand-to-mouth transfer, and toddlers' incidental ingestion of pesticide residues on carpet/textile indoor surfaces from hand-to-mouth transfer. Intermediate-term exposures were also estimated for infants and children for residential post-application oral exposures.

        The exposure estimates are based on some upper-percentile (i.e., maximum application rate, initial amount of transferrable residue and duration of exposure) and some central tendency (i.e., surface area, hand-to-mouth activity, and body weight) assumptions and are considered to be representative of high-end exposures. The uncertainties associated with this assessment stem from the use of an assumed amount of pesticide available from turf, and assumptions regarding transfer of chemical residues and hand-to mouth activity. The estimated exposures are believed to be reasonable high-end estimates.

      4. Cumulative effects from substances with a common mechanism of toxicity. Section 408(b)(2)(D)(v) of the FFDCA requires that, when considering whether to establish, modify, or revoke a tolerance, the Agency consider ``available information'' concerning the cumulative effects of a particular pesticide's residues and ``other substances that have a common mechanism of toxicity.''

        Unlike other pesticides for which EPA has followed a cumulative risk approach based on a common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as to azoxystrobin and any other substances and azoxystrobin 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 azoxystrobin has a common mechanism of toxicity with other substances. For information regarding EPA's efforts to determine which chemicals have a common mechanism of toxicity and to evaluate the cumulative effects of such chemicals, see the policy statements released by EPA's Office of Pesticide Programs concerning common mechanism determinations and procedures for cumulating effects from substances found to have a common mechanism on EPA's Web site at http://www.epa.gov/pesticides/cumulative .

    4. Safety Factor for Infants and Children

      1. In general. Section 408 of FFDCA provides that EPA shall apply an additional tenfold margin of safety for infants and children in the case of threshold effects to account for prenatal and postnatal toxicity and the completeness of the data base on toxicity and exposure unless EPA determines based on reliable data that a different margin of safety will be safe for infants and children. Margins of safety are incorporated into EPA risk assessments either directly through use of a MOE analysis or through using uncertainty (safety) factors in calculating a dose level that poses no appreciable risk to humans. In applying this provision, EPA either retains the default value of 10X when reliable data do not support the choice of a different factor, or, if reliable data are available, EPA uses a different additional safety factor value based on the use of traditional uncertainty factors and/or special FQPA safety factors, as appropriate.

      2. Prenatal and postnatal sensitivity. The developmental and reproductive toxicity data, from a Prenatal Development Study in Rats, a Prenatal Development Study in Rabbits, and a Two-Generation Reproductive Toxicity Study in Rats, did not indicate increased susceptibility of young rats or rabbits to in utero and/or postnatal exposure.

      3. Conclusion. There is a complete toxicity data base for azoxystrobin and exposure data are complete or are estimated based on data that reasonably account for potential exposures. The Agency has determined that the 10X FQPA safety factor to protect infants and children should be removed (that is, set to 1) because, in addition to the completeness of the toxicological database and the lack of increased susceptibility of young rats and rabbits to pre- and postnatal exposure to azoxystrobin, the unrefined acute and chronic dietary exposure estimates will overestimate dietary exposure from food, and ground and surface water modeling data produce upper-bound concentration estimates. The residential postapplication assessment is based upon the residential SOPs. The assessment is based upon surrogate study data. These data are reliable and are not expected to underestimate risk to adults or children. The residential SOPs are based upon reasonable ``worst-case'' assumptions and are not expected to underestimate risk.

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    5. Aggregate Risks and Determination of Safety

      The Agency currently has two ways to estimate total aggregate exposure to a pesticide from food, drinking water, and residential uses. First, a screening assessment can be used, in which the Agency calculates drinking water levels of comparison (DWLOCs) which are used as a point of comparison against estimated drinking water concentrations (EDWCs). The DWLOC values are not regulatory standards for drinking water, but are theoretical upper limits on a pesticide's concentration in drinking water in light of total aggregate exposure to a pesticide in food and residential uses. More information on the use of DWLOCs in dietary aggregate risk assessments can be found at http://www.epa.gov/oppfead1/trac/science/screeningsop.pdf .

      More recently the Agency has used another approach to estimate aggregate exposure through food, residential and drinking water pathways. In this approach, modeled surface and ground water EDWCs are directly incorporated into the dietary exposure analysis, along with food. This provides a more realistic estimate of exposure because actual body weights and water consumption from the CSFII are used. The combined food and water exposures are then added to estimated exposure from residential sources to calculate aggregate risks. The resulting exposure and risk estimates are still considered to be high end, due to the assumptions used in developing drinking water modeling inputs.

      1. Acute risk. Using the exposure assumptions discussed in this unit for acute exposure, the acute dietary exposure from food and water to azoxystrobin will occupy 27 % of the aPAD for the U.S. population, 24 % of the aPAD for females 13 years and older, 24 % of the aPAD for infants (

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