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Azoxystrobin - Pesticide Petition Filing 5/01

ENVIRONMENTAL PROTECTION AGENCY
[PF-1022; FRL-6782-2]
Notice of Filing a Pesticide Petition to Establish a Tolerance
for a Certain Pesticide Chemical in or on Food
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice.
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SUMMARY: This notice announces the initial filing of a pesticide
petition proposing the establishment of regulations for residues of a
certain pesticide chemical in or on various food commodities.

DATES: Comments, identified by docket control number PF-1022 must be
received on or before June 29, 2001.

ADDRESSES: Comments may be submitted by mail, electronically, or in
person. Please follow the detailed instructions for each method as
provided in Unit I.C. of the SUPPLEMENTARY INFORMATION. To ensure
proper receipt by EPA, it is imperative that you identify docket
control number PF-1022 in the subject line on the first page of your
response.

FOR FURTHER INFORMATION CONTACT: By mail: Shaja R. Brothers,
Registration Division (7505C), Office of Pesticide Programs,
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460; telephone number: (703) 308-3194; e-mail address:
brothers.shaja@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
           Categories                 NAICS codes         potentially
                                                       affected entities
------------------------------------------------------------------------
Industry                          111                 Crop production
------------------------------------------------------------------------
                                  112                 Animal production
------------------------------------------------------------------------
                                  311                 Food manufacturing
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                                  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 (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 under FOR FURTHER INFORMATION
CONTACT.

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", " Regulation and Proposed Rules", 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 PF-1022. The official record
consists of the documents specifically referenced in this action, any
public comments received during an applicable comment period, 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 Highway, 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.

C. How and to Whom Do I Submit Comments?

    You may submit comments through the mail, in person, or
electronically. To ensure proper receipt by EPA, it is imperative that
you identify docket control number PF-1022 in the subject line on the
first page of your response.
    1. By mail. Submit your comments to: Public Information and Records
Integrity Branch (PIRIB), Information Resources and Services Division
(7502C), Office of Pesticide Programs (OPP), Environmental Protection
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
    2. In person or by courier. Deliver your comments to: Public
Information and Records Integrity Branch (PIRIB), Information Resources
and Services
Division (7502C), Office of Pesticide Programs (OPP), Environmental
Protection Agency, Rm. 119, Crystal Mall #2, 1921 Jefferson Davis
Highway, Arlington, VA. The PIRIB is open from 8:30 a.m. to 4 p.m.,
Monday through Friday, excluding legal holidays. The PIRIB telephone
number is (703) 305-5805.
    3. Electronically. You may submit your comments electronically by
e-mail to: opp-docket@epa.gov, or you can submit a computer disk as
described above. Do not submit any information electronically that you
consider to be CBI. Avoid the use of special characters and any form of
encryption. Electronic submissions will be accepted in Wordperfect 6.1/
8.0 or ASCII file format. All comments in electronic form must be
identified by docket control number PF-1022. Electronic comments may
also be filed online at many Federal Depository Libraries.

D. How Should I Handle CBI That I Want to Submit to the Agency?

    Do not submit any information electronically that you consider to
be CBI. You may claim information that you submit to EPA in response to
this document as CBI 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. In addition to one complete
version of the comment that includes any information claimed as CBI, a
copy of the comment that does not contain the information claimed as
CBI must be submitted for inclusion in the public version of the
official record. Information not marked confidential will be included
in the public version of the official record without prior notice. If
you have any questions about CBI or the procedures for claiming CBI,
please consult the person identified under FOR FURTHER INFORMATION
CONTACT.

E. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide copies of any technical information and/or data you used
that support your views.
    4. If you estimate potential burden or costs, explain how you
arrived at the estimate that you provide.
    5. Provide specific examples to illustrate your concerns.
    6. Make sure to submit your comments by the deadline in this
notice.
    7. To ensure proper receipt by EPA, be sure to identify the docket
control number assigned to this action in the subject line on the first
page of your response. You may also provide the name, date, and Federal
Register citation.

II. What Action Is the Agency Taking?

    EPA has received a pesticide petition as follows proposing the
establishment and/or amendment of regulations for residues of a certain
pesticide chemical in or on various food commodities under section 408
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a.
EPA has determined that this petition contains data or information
regarding the elements set forth in section 408(d)(2); however, EPA has
not fully evaluated the sufficiency of the submitted data at this time
or whether the data support granting of the petition. Additional data
may be needed before EPA rules on the petition.

List of Subjects

    Environmental protection, Agricultural commodities, Feed additives,
Food additives, Pesticides and pests, Reporting and recordkeeping
requirements.

    Dated: May 16, 2001.
James Jones,
Director, Registration Division, Office of Pesticide Programs.

Summary of Petitions

    The petitioner summary of the pesticide petitions is printed below
as required by section 408(d)(3) of the FFDCA. The summary of the
petitions was prepared by the petitioner and represents the view of the
petitioner. EPA is publishing the petition summaries verbatim without
editing them in any way. The petition summararies announce the
availability of a description of the analytical methods available to
EPA for the detection and measurement of the pesticide chemical
residues or an explanation of why no such method is needed.

Interregional Research Project # 4 (IR-4)

PP 0E6211, 1E6238, and 1E6264

    EPA has received pesticide petitions (0E6211, 1E6238, and 1E6264)
from the Interregional Research Project Number 4 (IR-4), [681 US
Highway #1 South, North Brunswick, NJ 08902-3390 proposing, pursuant to
section 408(d) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21
U.S.C. 346a(d), to amend 40 CFR part 180.507 by establishing tolerances
for 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 the following raw agricultural
commodities (RACs):
    PP# 0E6211 proposes to establish tolerances for strawberry at 10
parts per million (ppm), mint at 30 ppm, grass forage (from grass grown
for seed) at 15 ppm, grass (from grass grown for seed) hay at 20 ppm,
and 3.0 ppm for watercress, tropical fruits, persimmon, paw paw,
tamarind, jackfruit, and loquat.
    PP# 1E6238 proposes to establish tolerances for bushberry subgroup,
lingonberries, juneberries, and salal at 3.0 ppm.
    PP# 1E6264 proposes to establish tolerances for the leafy brassica
greens subgroup and turnip greens at 25 ppm, and 2.0 ppm for pepper,
eggplant, and okra.
    EPA has determined that the petitions contain data or information
regarding the elements set forth in section 408(d)(2) of the FFDCA;
however, EPA has not fully evaluated the sufficiency of the submitted
data at this time or whether the data support granting of the
petitions. Additional data may be needed before EPA rules on these
petitions.

A. Residue Chemistry

    1. Plant metabolism. The metabolism of azoxystrobin as well as the
nature of the residues is adequately understood for purposes of the
tolerances.
    2. Analytical method. Gas chromatography with nitrogen-phosphorus
detection (GC-NPD) or in mobile phase by high performance liquid
chromatography with ultra-violet detection (HPLC-UV), is available. The
method(s) are adequate for enforcement purposes. Analytical methods are
also available for analyzing meat, milk, poultry and eggs which
underwent successful independent laboratory validations.
    3. Magnitude of residues. Complete residue data for azoxystrobin
(on legume vegetable group, hops, bushberries, lingonberries, salal,
juneberries, forage grass, forage hay, jackfruit, loquat, mint, fresh,
paw paw, peppermint, persimmon, spearmint, strawberry, tamarind,
tropical fruit, watercress, eggplant, leafy brassica subgroup, okra,
peppers, and turnip greens) have been submitted. The
requested tolerances are adequately supported.

B. Toxicological Profile

    1. Acute toxicity. The acute oral toxicity study in rats of
technical azoxystrobin resulted in a lethal dose (LD)50 of
5,000 milligrams/kilogram (mg/kg) for both males and females. The acute
dermal toxicity study in rats of technical azoxystrobin resulted in
a(LD)50 of 2,000 mg/kg. The acute inhalation study of
technical azoxystrobin in rats resulted in a lethal concentration
LC50 of 0.962 mg/liter (L) in males and 0.698 m/L in
females. In an acute oral neurotoxicity study in rats dosed once by
gavage with 0, 200, 600, or 2,000 mg/kg azoxystrobin, the systemic
toxicity no observed adverse effect level (NOAEL) was <200 mg/kg and
the systemic toxicity lowest observed adverse effect level (LOAEL) was
200 mg/kg, based on the occurrence of transient diarrhea in both sexes.
There was no indication of neurotoxicity at the doses tested.
    2. Genotoxicity. Azoxystrobin was negative for mutagenicity in the
salmonella/mammalian activation gene mutation assay, mouse micronucleus
test, and unscheduled deoxyribonucleic acid (DNA) synthesis in rat
hepatocytes/mammalian cells in vivo/in vitro procedure study. In the
forward mutation study using L5178 mouse lymphoma cells in culture,
azoxystrobin tested positive for forward gene mutation at the TK locus.
In the in vitro human lymphocytes cytogenetics assay of azoxystrobin,
there was evidence of a concentration related induction of chromosomal
aberrations over background in the presence of moderate to severe
cytotoxicity.
    3. Reproductive and developmental toxicity. In a prenatal
development study in rats gavaged with azoxystrobin at dose levels of
0, 25, 100, or 300 mg/kg/day during days 7 through 16 of gestation,
lethality at the highest dose caused the discontinuation of dosing at
that level. The developmental NOAEL was greater than or equal to 100
mg/kg/day and the developmental LOAEL was > 100 mg/kg/day because no
significant adverse developmental effects were observed. In this same
study, the maternal NOAEL was not established; the maternal LOAEL was
25 mg/kg/day, based on increased salivation.
    In a prenatal developmental study in rabbits gavaged with 0, 50,
150, or 500 mg/kg/day during days 8 through 20 of gestation, the
developmental NOAEL was 500 mg/kg/day and the developmental LOAEL was
> 500 mg/kg/day because no treatment-related adverse effects on
development were seen. The maternal NOAEL was 150 mg/kg/day and the
maternal LOAEL was 500 mg/kg/day, based on decreased body weight gain.
    In a 2-generation reproduction study, rats were fed 0, 60, 300, or
1,500 ppm of azoxystrobin. The reproductive NOAEL was 32.2 mg/kg/day.
The reproductive LOAEL was 165.4 mg/kg/day; reproductive toxicity was
demonstrated as treatment-related reductions in adjusted pup body
weights as observed in the F18 and F2 pups dosed at 1,500 ppm (165.4
mg/kg/day).
    4. Subchronic toxicity. In a 90-day rat feeding study the NOAEL was
20.4 mg/kg/day for males and females. The LOAEL was 211 mg/kg/day based
on decreased weight gain in both sexes, clinical observations of
distended abdomens and reduced body size, and clinical pathology
findings attributable to reduced nutritional status.
    In a subchronic toxicity study in which azoxystrobin was
administered to dogs by capsule for 92 or 93 days, the NOAEL for both
males and females was 50 mg/kg/day. The LOAEL was 250 mg/kg/day, based
on treatment-related clinical observations and clinical chemistry
alterations at this dose.
    In a 21-day repeated-dose dermal rat study using azoxystrobin, the
NOAEL for both males and females was greater than or equal to 1,000 mg/
kg/day (the highest dosing regimen); a LOAEL was therefore not
determined.
    5. Chronic toxicity. In a 2-year feeding study in rat fed diets
containing 0, 60, 300, and 750/1,500 ppm (males/females), the systemic
toxicity NOAEL was 18.2 mg/kg/day for males and 22.3 mg/kg/day for
females. The systemic toxicity LOAEL for males was 34 mg/kg/day, based
on reduced body weights, food consumption and efficiency, and bile duct
lesions. The systemic toxicity LOAEL for females was 117.1 mg/kg/day,
based on reduced body weights. There was no evidence of carcinogenic
activity in this study.
    In a 1-year feeding study in dogs to which azoxystrobin was fed by
capsule at doses of 0, 3, 25, or 200 mg/kg/day, the NOAEL for both
males and females was 25 mg/kg/day and the LOAEL was 200 mg/kg/day for
both sexes, based on clinical observations, clinical chemistry changes,
and liver weight increases that were observed in both sexes.
    In a 2-year carcinogenicity feeding study in mice using dosing
concentrations of 0, 50, 300, or 2,000 ppm, the systemic toxicity NOAEL
was 37.5 mg/kg/day for both males and females. The systemic toxicity
LOAEL was 272.4 mg/kg/day for both sexes, based on reduced body weights
in both at this dose. There was no evidence of carcinogenicity at the
dose levels tested.
    According to the new proposed guidelines for Carcinogen Risk
Assessment, the appropriate descriptor for human carcinogenic potential
of azoxystrobin is "Not Likely." The appropriate subdescriptor is
"has been evaluated in at least two well conducted studies in two
appropriate species without demonstrating carcinogenic effects."
    6. Animal metabolism. In this study, azoxystrobin unlabeled or with
a pyrimidinyl, phenylacrylate, or cyanophenyl label was administered to
rats by gavage as a single or 14-day repeated doses. Less than 0.5% of
the administered dose was detected in the tissues and carcass up to 7
days post-dosing-most of it was in excretion-related organs. There was
no evidence of potential for bioaccumulation. The primary route of
excretion was via the feces, though 9 to 18% was detected in the urine
of the various dose groups. Absorbed azoxystrobin appeared to be
extensively metabolized. A metabolic pathway was proposed showing
hydrolysis and subsequent glucuronide conjugation as the major
biotransformation process.
    7. Metabolite toxicology. There are no metabolites of concern based
on the differential metabolism between plants and animals.
    8. Endocrine disruption. There is no evidence that azoxystrobin is
an endocrine disrupter.

C. Aggregate Exposure

    1. Dietary exposure. Permanent tolerances have been established (40
CFR 180.507(a)) for the combined residues of azoxystrobin and its Z
isomer, in or on a variety of RACs at levels ranging from 0.02 ppm on
tree nuts to 50.0 ppm on leaves of root and tuber vegetables. Included
in these tolerances are animal commodities which were established in
conjunction with tolerances for animal feed.
    i. Food. For the purposes of assessing the potential acute and
chronic dietary exposure, Syngenta has estimated acute and chronic
exposure for all registered crops, (EPA) pending uses, and newly
proposed uses. Novigen Sciences', Inc. Dietary Exposure Evaluation
Model (DEEM), which is licensed to Syngenta, was used to estimate the
chronic and acute dietary exposure.
    a. Acute. The DEEM model was used for analysis of individual food
consumption as reported by the USDA using the Tier I analysis. The Tier
I analysis used tolerance values as anticipated residues. Syngenta's
acute dietary exposure assessment estimated
percent of the acute population adjusted dose (aPAD) and corresponding
margins of exposure (MOE) for the overall U.S. population, infants/
children, and females 13+ as presented in Table 1.

        Table 1.--Acute Dietary Risk Assessment for Azoxystrobin
------------------------------------------------------------------------
                              Exposure (mg/kg/
  Population Subgroup               day)            Percent aPAD
------------------------------------------------------------------------
U.S. population (total)           0.094350            14.0%
------------------------------------------------------------------------
Infants/children                  0.151589            22.6%
------------------------------------------------------------------------
Females 13+                       0.088553            13.2%
------------------------------------------------------------------------

    b. Chronic. In conducting this chronic dietary risk assessment
Syngenta has made very conservative assumptions--100% of all
commodities having azoxystrobin tolerances or proposed tolerances will
contain azoxystrobin residues at the level of the tolerance. Default
concentration factors have been removed where data show no
concentration of residues (grape juice, grapes, raisins; tomatoes
juice, tomatoes, puree; and white/dry potatoes). The chronic reference
dose (RfD) = 0.18 mg/kg/day.
    The existing azoxystrobin tolerances published and pending result
in a theoretical maximum residue contribution (TMRC) that is equivalent
to the following percentage of the Chronic RfD. As the 10X safety
factor was removed by EPA, the chronic RfD is equal to the PAD
(population-adjusted dose). As a result, the exposure given as a
percentage of the total allowable is reported as %PAD. These results
are presented in Table 2.

       Table 2.--Chronic Dietary Risk Assessment for Azoxystrobin
------------------------------------------------------------------------
                                                       Percent Reference
       Population Subgroup         Exposure (mg/kg/    Dose\1\ (%Chronic
                                         day)              PAD/RfD)
------------------------------------------------------------------------
U.S. population (total)           0.028977            16.1%
------------------------------------------------------------------------
All infants 1 year                0.026769            14.9%
------------------------------------------------------------------------
Nursing infants 1 year            0008527              4.7%
------------------------------------------------------------------------
Non-nursing infants 1 year        0.032107            17.8%
------------------------------------------------------------------------
Children (1-6 years old)          0.047504            26.4%
------------------------------------------------------------------------

Children (7-12 years old)         0.031544            17.5%
------------------------------------------------------------------------
Western region                    0.031923            17.7%
------------------------------------------------------------------------
Non-hispanic/non-white/non-black  0.044724            24.8%
------------------------------------------------------------------------
Females 13+ (nursing)             0.031485            17.5%
------------------------------------------------------------------------
\1\ Percentage reference dose (%Chronic PAD)= Exposure x 100% (as
  RfD=PAD in this case) Chronic PAD

    ii. Drinking water. There is no established Maximum Concentration
Level for residues of azoxystrobin in drinking water. No health
advisory levels for azoxystrobin in drinking water have been
established. The concentration of azoxystrobin in surface water based
on GENEEC (Generic Estimated Environmental Concentration ) modeling and
in ground water based on Screening Concentration in Ground Water (SCI-
GROW) modeling.
    Based on the chronic dietary (food) exposure estimated, chronic
drinking water levels of concern (DWLOC) for azoxystrobin were
calculated and summarized in the table below. EPA has estimated the
highest EEC of azoxystrobin in surface water is from the application of
azoxystrobin on grapes (39 μg/L). The estimated environmental
concentration (EEC) for ground water is 0.064 μg/L resulting
from use on turf. For purposes of risk assessment, the maximum EEC for
azoxystrobin in drinking water (39 μg/L) should be used for
comparison to the back-calculated human health drinking water levels of
comparison (DWLOC) for the chronic (non-cancer) endpoint. These DWLOCs
for various populations categories are summarized in Tables 3 and 4.

                Table 3.--Drinking Water Levels of Comparison for Acute Exposure to Azoxystrobin
-----------------------------------------------------------------------------------------------------
Maximum Water
   Subgroup\1\             aPAD (mg/kg/day)   Food Exposure (mg/   Exposure (mg/kg/   DWLOC (μg/L)
                                                      kg/day)             day)                
-----------------------------------------------------------------------------------------------------
U.S. population                   0.67                0.094350 0.57565             20147.7 5
-----------------------------------------------------------------------------------------------------
Females 13+ (nursing)             0.67                0.088553 0.581447            17443.41
-----------------------------------------------------------------------------------------------------

Children (1-6 years old)          0.67                0.151589 0.518411            5184.11
-----------------------------------------------------------------------------------------------------
\1\ Within each of these categories, the subgroup with the highest food exposure was selected.

                Table 4.--Drinking Water Level of Comparison for Chronic Exposure to Azoxystrobin
----------------------------------------------------------------------------------------------------------------
Max Water
   Subgroup\1\             cPAD (mg/kg/day)   Food Exposure (mg/  Exposure\2\ (mg/kg/    DWLOC \3,4,5\
                                                    kg/day) day)           (μg/L)
----------------------------------------------------------------------------------------------------------------
U.S. population                   0.18                0.028977 0.151023            5285.805
----------------------------------------------------------------------------------------------------------------
Females 13+ (nursing)             0.18                0.031485 0.148515            4455.45
----------------------------------------------------------------------------------------------------------------
Children (1-6 years old)          0.18                0.047504 0.132496            1324.96
----------------------------------------------------------------------------------------------------------------
\1\ Within each of these categories, the subgroup with the highest food exposure was selected.
\2\ Maximum Water Exposure (Chronic) (mg/kg/day) = Chronic RfD(mg/kg/day)-Food Exposure (mg/kg/day).
\3\ DWLOC (μg/L) = Max. water exposure (mg/kg/day) x body wt (kg)  (10-3 μg/μg)
  * water consumed daily (L/day).
\4\ HED default body weights are: General U.S. population, 70 kg; Females 13+ years old 60 kg; infants and
  children 10 kg.
\5\ HED Default daily drinking rates are 2 L/day for adults and 1 L/day for children.

    2. Non-dietary exposure. Azoxystrobin is registered for residential
use on ornamentals and turf. The Agency evaluated the existing
toxicological data base for azoxystrobin and assessed appropriate
toxicological endpoints and dose levels of concern that should be
assessed for risk assessment purposes. Dermal absorption data indicate
that absorption is less than or equal to 4%. Azoxystrobin is currently
registered for uses that could result in intermediate-term residential
exposure and the Agency has determined that is appropriate to aggregate
chronic food and water and intermediate-term exposures for
azoxystrobin. EPA has concluded that food and residential exposures
aggregated result in MOEs of 520 (aggregate short-term), and 420
(aggregate intermediate term) for the subgroup children 1-6 years old.

D. Cumulative Effects

    Azoxystrobin is related to the naturally occurring strobilurins.
Syngenta concluded that further consideration of a common mechanism of
toxicity is not appropriate at this time since there are no data to
establish whether a common mechanism exists with any other substance.

E. Safety Determination

    1. U.S. population. Based on the exposure assessments described and
completeness and reliability of the toxicity data, it can be concluded
that there is reasonable certainty that no harm will result from
aggregate exposure to azoxystrobin. Total aggregate exposures for all
label uses will utilize less than 16.1% of the cPAD for the chronic
dietary exposures.
    2. Infants and children. 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 prenatal and postnatal
toxicity and the completeness of the data base 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. In either case, EPA generally
defines the level of appreciable risk as exposure that is greater than
1/100 of the NOAEL in the animal study appropriate to the particular
risk assessment. This hundredfold uncertainty (safety) factor/margin of
exposure (safety) is designed to account for combined inter- and intra-
species variability. EPA believes that reliable data support using the
standard hundredfold margin/factor not the additional tenfold margin/
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 margin/factor. The Agency's Food
Quality Protection Act (FQPA) Safety Factor Committee removed the
additional 10X safety factor to account for sensitivity of infants and
children.

F. International Tolerances

    There are no Codex Maximum Residue Level's established for
azoxystrobin.
[FR Doc. 01-13515 Filed 5-29-01; 8:45 am]