[Federal Register Volume 66, Number 163 (Wednesday, August 22, 2001)]
[Notices]
[Pages 44136-44141]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-21048]


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ENVIRONMENTAL PROTECTION AGENCY

[PF-1035; FRL-6794-6]


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-1035, must be 
received on or before September 21, 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-1035 in the subject line on the first page of your 
response.

FOR FURTHER INFORMATION CONTACT: By mail: Cynthia Giles-Parker, 
Fungicide Branch, Registration Division (7505C),

[[Page 44137]]

Office of Pesticide Programs, Environmental Protection Agency, 1200 
Pennsylvania Ave., NW., Washington, DC 20460; telephone number: (703) 
305-7740; e-mail address: [email protected].

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
                                  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'' 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-1035. 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-1035 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: [email protected], 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-1035. 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

[[Page 44138]]

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: August 8, 2001.
James Jones,
Director, Registration Division, Office of Pesticide Programs.

Summary of Petition

    The petitioner summary of the pesticide petition is printed below 
as required by section 408(d)(3) of the FFDCA. The summary of the 
petition was prepared by the petitioner and represents the view of the 
petitioner. EPA is publishing the petition summary verbatim without 
editing it in any way. The petition summary announces 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.

 Syngenta Crop Protection, Inc.

0F6218

    EPA has received a pesticide petition (0F6218) from Syngenta Crop 
Protection, Inc., 410 Swing Road, P.O. Box 18300, Greensboro, North 
Carolina 27409-8300 proposing, pursuant to section 408(d) of the FFDCA, 
21 U.S.C. 346a(d), to amend 40 CFR part 180 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 raw agricultural 
commodities legume vegetables (succulent or dried) group at 3 parts per 
million (ppm), hops at 50 ppm, grapes at 3 ppm, tomatoes at 2 ppm, and 
tomato paste at 6 ppm. The proposed tolerance in or on grapes is an 
increase from the current tolerance of 1.0 ppm, the proposed tolerance 
in or on tomatoes is an increase from the current tolerance of 0.2 ppm, 
and the proposed tolerance in or on tomato paste is an increase from 
the current tolerance of 0.6 ppm. The proposed tolerances on legume 
vegetables (succulent or dried) group and hops are new. EPA has 
determined that the petition contains 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 petition. Additional data 
may be needed before EPA rules on the petition.

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. Plant metabolism has been evaluated in four diverse crops, 
cotton, grapes, wheat and peanuts, which should serve to define the 
similar metabolism of azoxystrobin in a wide range of crops. Parent 
azoxystrobin is the major component found in crops. Azoxystrobin does 
not accumulate in crop seeds or fruits. Metabolism of azoxystrobin in 
plants is complex with more than 15 metabolites identified. These 
metabolites are present at low levels, typically much less than 5% of 
the total recoverable residue (TRR).
    2. Analytical method. An adequate 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 for enforcement purposes with a limit 
of detection that allows monitoring of food with residues at or above 
the levels set in these tolerances. EPA concluded that the method(s) 
are adequate for enforcement. Analytical methods are also available for 
analyzing meat, milk, poultry, and eggs, and also underwent successful 
independent laboratory validations.
    3. Magnitude of residues. Nineteen residue trials in legume 
vegetables were carried out in the United States and Canada in 1998 and 
1999. Maximum residues of 1.9 ppm resulted from multiple foliar 
applications. Six residue trials in hops were carried out in the United 
Kingdom and Germany in 1998 and 1999. Maximum residues were 16 ppm. In 
the interest of harmonizing United States tolerances with those of 
Canada and the European Union, representative residue data from Canada 
and Germany are presented that demonstrate maximum residues of 2.4 ppm 
in grapes and 1.3 ppm in tomatoes.

B. Toxicological Profile

    1. Acute toxicity. The acute oral toxicity study in rats of 
technical azoxystrobin resulted in an LD50 of > 5,000 
milligrams/kilogram (mg/kg limit test) for both males and females. The 
acute dermal toxicity study in rats of technical azoxystrobin resulted 
in an LD50 of > 2,000 mg/kg (limit dose). The acute 
inhalation study of technical azoxystrobin in rats resulted in an 
LC50 of 0.962 milligrams/liter (mg/L) in males and 0.698 mg/
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 NOAEL 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, the mouse 
micronucleus test, and the 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 milligrams per kilogram per day (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 lowest 
observed adverse effect level (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

[[Page 44139]]

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 211.0 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 and carcinogenicity. In a 2-year feeding study 
in rats 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 food 
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 (April 1996), 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 as 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 and 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 a differential metabolism between plants and animals.
    8. Endocrine disruption. There is no evidence that azoxystrobin is 
an endocrine disrupter.

C. Aggregate Exposure

    The Agency has concluded from review of available data that there 
is no acute toxicological endpoint of concern. Therefore, an acute risk 
assessment is not necessary. For azoxystrobin, only a chronic 
(noncancer) risk assessment is necessary.
    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 raw agricultural commodities at levels 
ranging from 0.02 ppm on tree nuts to 20.0 ppm on rice hulls. Included 
in these tolerances are numerous ones for animal commodities, 
established in conjunction with tolerances for rice and wheat 
commodities.
    i. Food. In conducting this chronic dietary risk assessment, 
Syngenta has made the very conservative assumption that 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 (grapes, juice; grapes, raisins; tomatoes, 
juice; tomatoes, puree; and potatoes, white (dry)). The chronic 
reference dose (RfD) is 0.18 mg/kg/day, derived from the NOAEL of 18.2 
mg/kg/day from the rat chronic toxicity/carcinogenicity feeding study 
and an uncertainty factor of 100 to allow for interspecies sensitivity 
and intraspecies variability.
    The Novigen DEEM (Dietary Exposure Evaluation Model) system was 
used for this chronic dietary exposure analysis. The analysis evaluates 
individual food consumption as reported by respondents in the USDA 
Continuing Surveys of Food Intake by Individuals conducted in 1994 
through 1996. The model accumulates exposure to the chemical for each 
commodity and expresses risk as a function of dietary exposure.
    The existing azoxystrobin tolerances (published and pending; FIFRA 
section 18 tolerances were excluded in this analysis because most are 
included as pending tolerances), result in a theoretical maximum 
residue contribution (TMRC) that is equivalent to the following 
percentages of the chronic RfD. Because 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.

------------------------------------------------------------------------
                                                       Percent Reference
    Population Group/Subgroup      Exposure (mg/kg/     Dose1 (%Chronic
                                         day)              PAD/RfD)
------------------------------------------------------------------------
U.S. population                   0.033665            18.7
------------------------------------------------------------------------
All infants (< 1-year)            0.043793            24.3
------------------------------------------------------------------------
Nursing infants (< 1-year)        0.015041             8.4
------------------------------------------------------------------------
Non-Nursing infants (< 1-year)    0.052206            29.0
------------------------------------------------------------------------
Children (1-6 years old)          0.069628            38.7
------------------------------------------------------------------------
Children (7-12 years old)         0.040975            22.8
------------------------------------------------------------------------
Hispanics                         0.038407            21.3
------------------------------------------------------------------------
Non-Hispanic/non-white/non-black  0.046447            25.8
------------------------------------------------------------------------

[[Page 44140]]

 
Females 13+ (nursing)             0.035904            19.9
------------------------------------------------------------------------
1Percentage reference dose (% chronic PAD) = exposure x 100% (because
  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 is 
based on Generic Estimated Environmental Concentration (GENEEC) 
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 are summarized in the following table. EPA has estimated 
that the highest estimated environmental concentration EEC of 
azoxystrobin in surface water is from the application of azoxystrobin 
on grapes (39 g/L). The EEC for ground water is 0.064 
g/L resulting from use on turf. For purposes of risk 
assessment the maximum EEC for azoxystrobin in drinking water (39 
g/L) should be used for comparison to the back-calculated 
human health drinking water levels of comparison (DWLOC) for the 
chronic (noncancer) endpoint. These DWLOCs for various population 
categories are summarized in the following table.

----------------------------------------------------------------------------------------------------------------
                                                                             Maximum Water
         Group/Subgroup1            RfD (mg/kg/day)   TMRC (food) (mg/kg/  Exposure2 (mg/kg/   DWLOC3, 4, 5(g/L)
                                                             day)                day)
----------------------------------------------------------------------------------------------------------------
U.S. population                   0.18                0.033665            0.146335            5121.725
----------------------------------------------------------------------------------------------------------------
Females 13+ (nursing)             0.18                0.035904            0.144096            4322.88
----------------------------------------------------------------------------------------------------------------
Children (1-6 years old)          0.18                0.069628            0.110372            1103.72
----------------------------------------------------------------------------------------------------------------
1 Within each of these categories, the subgroup with the highest food exposure was selected
2 Maximum chronic water exposure (mg/kg/day) = chronic RfD (mg/kg/day) - food exposure (mg/kg/day)
3 DWLOC (g/L) = maximum water exposure (mg/kg/day) X body wt (kg)  (10-3 mg/g) X water
  consumed daily (L/day)
4 HED default body weights are: 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%. No appropriate endpoints 
were identified for acute dietary or short-term, intermediate-term, and 
chronic term (noncancer) dermal and inhalation occupational exposure. 
Therefore, risk assessments are not required for these exposure 
scenarios.

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

    The acute safety analysis was not applicable since no suitable 
toxicological end-point of concern was identified during Agency review 
of the available data. The short-term and intermediate-term safety 
assessment also was not applicable, in this case because no indoor and 
outdoor residential exposure uses are currently registered for 
azoxystrobin. Therefore, only a chronic analysis was needed.
    1. U.S. population. The chronic dietary exposure analysis showed 
that exposure from all existing permanent and proposed tolerances, 
including those in or on legume vegetables (succulent or dry) group, 
hops, grape and tomato for the general U.S. population would be 18.7% 
of the RfD.
    2. Infants and children. The chronic dietary exposure analysis 
showed that exposure from all existing permanent and proposed 
tolerances, including those in or on legume vegetables (succulent or 
dry) group, hops, grape and tomato for children (1-6 years old), the 
subgroup with the highest exposure, would be 38.7% of the RfD.
    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 
no observed effect level 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 
interspecies and intraspecies variability. EPA believes that reliable 
data support using the standard hundredfold margin/factor but 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 ad hoc FQPA Safety Factor Committee removed 
the additional 10x safety factor because infants and children are not 
believed to have an increased sensitivity to azoxystrobin, compared to 
adults.
    Syngenta has considered the potential aggregate exposure from food, 
water, and non-occupational exposure routes and concludes that 
aggregate exposure is not expected to exceed 100% of the RfD and that 
there is a reasonable certainty that no harm will result to infants and 
children from aggregate exposure to azoxystrobin residues.

F. International Tolerances

    There are no Codex Maximum Residue Levels established for 
azoxystrobin.
[FR Doc. 01-21048 Filed 8-21-01; 8:45 am]
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