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Chlorfenapyr (BASF) . July 16, 2003. Petition for pesticide tolerance. Federal Register.
http://www.epa.gov/fedrgstr/EPA-PEST/2003/July/Day-16/p17900.htm
[Federal Register: July 16, 2003 (Volume 68, Number 136)]
[Notices]
[Page 42022-42026]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16jy03-80]
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ENVIRONMENTAL PROTECTION AGENCY
[OPP-2003-0205; FRL-7312-7]
Chlorfenapyr; 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 ID number OPP-2003-0205, must be
received on or before August 15, 2003.
ADDRESSES: Comments may be submitted electronically, by mail, or
through hand delivery/courier. Follow the detailed instructions as
provided in Unit I. of the SUPPLEMENTARY INFORMATION.
FOR FURTHER INFORMATION CONTACT: Ann Sibold, Registration Division
(7505C), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone
number: (703) 305-6502; e-mail address: sibold.ann@epa.gov.
SUPPLEMENTARY INFORMATION:
I. General Information
A. Does this Action Apply to Me?
You may be potentially affected by this action if you are a
commercial processor of food, or use pesticides to control pests in
food processing operations. Potentially affected entities may include,
but are not limited to:
¥ Crop production (NAICS 111)
¥ Animal production (NAICS 112)
¥ Food manufacturing (NAICS 311)
¥ Pesticide manufacturing (NAICS 32532)
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.
B. How Can I Get Copies of this Document and Other Related Information?
1. EPA Docket. EPA has established an official public docket for
this action under docket ID number OPP-2003-0205. The official public
docket consists of the documents specifically referenced in this
action, any public comments received, and other information related to
this action. Although, a part of the official docket, the public docket
does not include Confidential Business Information (CBI) or other
information whose disclosure is restricted by statute. The official
public docket is the collection of materials that is available for
public viewing at the Public Information and Records Integrity Branch
(PIRIB), Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy.,
Arlington, VA. This 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.
2. Electronic access. You may access this Federal Register document
electronically through the EPA Internet under the ``Federal Register''
listings at http://www.epa.gov/fedrgstr/.
An electronic version of the public docket is available through
EPA's electronic public docket and comment system, EPA dockets. You may
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public
comments, access the index listing of the contents of the official
public docket, and to access those documents in the public docket that
are available electronically. Although, not all docket materials may be
available electronically, you may still access any of the publicly
available docket materials through the docket facility identified in
Unit I.B.1. Once in the system, select ``search,'' then key in the
appropriate docket ID number.
Certain types of information will not be placed in the EPA
Dockets. Information claimed as CBI and other information whose
disclosure is restricted by statute, which is not included in the
official public docket, will not be available for public viewing in
EPA's electronic public docket. EPA's policy is that copyrighted
material will not be placed in EPA's electronic public docket but will
be available only in printed, paper form in the official public docket.
To the extent feasible, publicly available docket materials will be
made available in EPA's electronic public docket. When a document is
selected from the index list in EPA dockets, the system will identify
whether the document is available for viewing in EPA's electronic
public docket. Although, not all docket materials may be available
electronically, you may still access any of the publicly available
docket materials through the docket facility identified in Unit I.B.
EPA intends to work towards providing electronic access to all of the
publicly available docket materials through EPA's electronic public
docket.
For public commenters, it is important to note that EPA's policy
is that public comments, whether submitted electronically or on paper,
will be made available for public viewing in EPA's electronic public
docket as EPA receives them and without change, unless the comment
contains copyrighted material, CBI, or other information whose
disclosure is restricted by statute. When EPA identifies a comment
containing copyrighted material, EPA will provide a reference to that
material in the version of the comment that is placed in EPA's
electronic public docket. The entire printed comment, including the
copyrighted material, will be available in the public docket.
Public comments submitted on computer disks that are mailed or
delivered to the docket will be transferred to EPA's electronic public
docket. Public comments that are mailed or delivered to the docket will
be scanned and placed in EPA's electronic public docket. Where
practical, physical objects will be photographed, and the photograph
will be placed in EPA's electronic public docket along with a brief
description written by the docket staff.
C. How and to Whom Do I Submit Comments?
You may submit comments electronically, by mail, or through hand
delivery/courier. To ensure proper
[[Page 42023]]
receipt by EPA, identify the appropriate docket ID number in the
subject line on the first page of your comment. Please ensure that your
comments are submitted within the specified comment period. Comments
received after the close of the comment period will be marked ``late.''
EPA is not required to consider these late comments. If you wish to
submit CBI or information that is otherwise protected by statute,
please follow the instructions in Unit I.D. Do not use EPA dockets or
e-mail to submit CBI or information protected by statute.
1. Electronically. If you submit an electronic comment as
prescribed in this unit, EPA recommends that you include your name,
mailing address, and an e-mail address or other contact information in
the body of your comment. Also, include this contact information on the
outside of any disk or CD ROM you submit, and in any cover letter
accompanying the disk or CD ROM. This ensures that you can be
identified as the submitter of the comment and allows EPA to contact
you in case EPA cannot read your comment due to technical difficulties
or needs further information on the substance of your comment. EPA's
policy is that EPA will not edit your comment, and any identifying or
contact information provided in the body of a comment will be included
as part of the comment that is placed in the official public docket,
and made available in EPA's electronic public docket. If EPA cannot
read your comment due to technical difficulties and cannot contact you
for clarification, EPA may not be able to consider your comment.
i. EPA Dockets. Your use of EPA's electronic public docket to
submit comments to EPA electronically is EPA's preferred method for
receiving comments. Go directly to EPA Dockets at http://www.epa.gov/
edocket, and follow the online instructions for submitting comments.
Once in the system, select ``search,'' and then key in docket ID number
OPP-2003-0205. The system is an ``anonymous access'' system, which
means EPA will not know your identity, e-mail address, or other contact
information unless you provide it in the body of your comment.
ii. E-mail. Comments may be sent by e-mail to opp-docket@epa.gov,
Attention: Docket ID number OPP-2003-0205. In contrast to EPA's
electronic public docket, EPA's e-mail system is not an ``anonymous
access'' system. If you send an e-mail comment directly to the docket
without going through EPA's electronic public docket, EPA's e-mail
system automatically captures your e-mail address. E-mail addresses
that are automatically captured by EPA's e-mail system are included as
part of the comment that is placed in the official public docket, and
made available in EPA's electronic public docket.
iii. Disk or CD ROM. You may submit comments on a disk or CD ROM
that you mail to the mailing address identified in Unit I.C.2. These
electronic submissions will be accepted in WordPerfect or ASCII file
format. Avoid the use of special characters and any form of encryption.
2. By mail. Send your comments to: Public Information and Records
Integrity Branch (PIRIB) (7502C), Office of Pesticide Programs (OPP),
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460-0001, Attention: Docket ID number OPP-2003-0205.
3. By hand delivery or courier. Deliver your comments to: Public
Information and Records Integrity Branch (PIRIB), Office of Pesticide
Programs (OPP), Environmental Protection Agency, Rm. 119, Crystal Mall
#2, 1921 Jefferson Davis Hwy., Arlington, VA, Attention: Docket
ID number OPP-2003-0205. Such deliveries are only accepted during the
docket's normal hours of operation as identified in Unit I.B.1.
D. How Should I Submit CBI to the Agency?
Do not submit information that you consider to be CBI
electronically through EPA's electronic public docket or by e-mail. You
may claim information that you submit to EPA as CBI by marking any part
or all of that information as CBI (if you submit CBI on disk or CD ROM,
mark the outside of the disk or CD ROM as CBI and then identify
electronically within the disk or CD ROM the specific information that
is 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 docket and EPA's electronic public docket. If you submit
the copy that does not contain CBI on disk or CD ROM, mark the outside
of the disk or CD ROM clearly that it does not contain CBI. Information
not marked as CBI will be included in the public docket and EPA's
electronic public docket without prior notice. If you have any
questions about CBI or the procedures for claiming CBI, please consult
the person listed 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
ID 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 FFDCA 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: July 2, 2003.
Debra Edwards,
Director, Registration Division, Office of Pesticide Programs.
Summary of Petition
The petitioner summary of the pesticide petition is printed below
as required by FFDCA section 408(d)(3). The summary of the petition was
prepared by BASF Corporation and represents the view of the petitioner.
The petition summary announces the availability of a description of the
analytical methods available to EPA for the detection and measurement
of the
[[Page 42024]]
pesticide chemical residues or an explanation of why no such method is
needed.
BASF Corporation
PP 3F6560
EPA has received a pesticide petition (PP 3F6560) from BASF
Corporation, 26 Davis Drive, Research Triangle Park, NC 27709-3528
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, by
establishing a tolerance for residues of chlorfenapyr, [4-bromo-2-(4-
chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)-1H-pyrrole-3-
carbonitrile]
on all food items in food handling establishments where
food products are held, processed, and/or prepared at 0.01 parts per
million (ppm). 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 nature of the residues of chlorfenapyr in
plants (tomato, citrus, potato and head lettuce) is adequately
understood and the residue of concern consists of the parent molecule.
The metabolic pathway of chlorfenapyr in the laying hen and the
lactating goat was also similar to that in laboratory rats.
2. Analytical method. The GC analytical method, M 2398, which is
proposed as the enforcement method for the residue of chlorfenapyr in
or on food commodities, has a limit of quantitation (LOQ) of 0.01 ppm.
3. Magnitude of residues. A study, based on protocol
recommendations outlined in EPA's Residue Chemistry Test Guidelines,
(OPPTS Harmonized Test Guideline 860.1460: Food Handling), was
conducted with chlorfenapyr formulated as a 24% wettable powder.
Applications were made to all potential sites within a commercial
kitchen, including the perimeter of the restaurant kitchen, areas under
cabinets and overhead cabinets, behind and on sides of cabinets and
appliances, within the ceiling voids, and around pipes, cords, cables,
counter legs, and wheels. The areas in which the product was applied
are typical of those treated in a professional pest control operation
in a commercial kitchen.
The test was conducted using a wettable powder (WP) formulation at
the maximum label rate for indoor use of 0.5% active ingredient (a.i.)/
1,000 ft2, which is also the approved maximum rate for
indoor use in non-food/feed areas for the SC formulation (suspension in
water), EPA Registration No. 241-392. The WP formulation has a larger
particle size and will be more easily dispersed than the SC
formulation, and therefore will best characterize the potential for
exaggerated exposures to food items.
Results from this study were that magnitudes of residues in all
composite meal samples, both covered and uncovered, were below the LOQ
of 10 parts per billion (ppb). Thus, there is a reasonable expectation
that no finite residues of chlorfenapyr will result in food items
following crack and crevice or spot applications of either the 25%
wettable powder or the 21% suspension concentrate.
B. Toxicological Profile
The toxicity of chlorfenapyr has been studied extensively and
there is a complete data base to address the acute and chronic effects,
effects on genetic material, the potential for carcinogenicity or
teratogenicity, and effects on reproductive performance or growth of
offspring. Toxicological data submitted previously that support this
petition for tolerances of chlorfenapyr include:
1. Acute toxicity. Based on EPA's toxicity category criteria, the
acute toxicity category for chlorfenapyr technical, EPA Registration
No. 241-366, is Category II or moderately toxic (signal word WARNING)
and the acute toxicity category for the 2SC formulation, EPA
Registration Nos. 241-374 and 241-392, is Category III or slightly
toxic (signal word CAUTION). Males appear to be more sensitive to the
effects of chlorfenapyr than females. The acute toxicity profile
indicates that absorption by the oral route appears to be greater than
by the dermal route. The following are the results from the acute
toxicity tests conducted on the technical material.
i. Rat Oral, LD50 of 441/1,152 milligrams/kilogram body
weight (mg/kg bwt) modifying factor (M/F) - Toxicology Category II.
ii. Rabbit Dermal LD50: >2,000 mg/kg bwt M/F Toxicology
Category III.
iii. Acute Inhalation LC50: 0.83/ >2.7 milligrams per
liter (mg/L) M/F Toxicology Category III.
iv. Eye irritation: Moderately irritating - Toxicology Category
III.
v. Dermal irritation: Non-irritating - Toxicology Category IV.
vi. Dermal sensitization: Non-sensitizer - Non sensitizer.
vii. Acute neurotoxicity: NOEL 45 mg/kg bwt. Not an acute
neurotoxicant
2. Genotoxicity. Chlorfenapyr technical (94.5%) was examined in a
battery of in vitro and in vivo tests to assess its genotoxicity and
its potential for carcinogenicity. These tests are summarized below.
i. Microbial/Microsome Mutagenicity Assay: Non-mutagenic.
ii. Mammalian Cell CHO/HGPRT Mutagenicity Assay: Non-mutagenic.
iii. In vivo Micronucleus Assay: Non-genotoxic.
iv. In vitro Chromosome Aberration Assay in CHO: Non-clastogenic.
v. In vitro Abberation Assay in CHLC: Non-clastogenic.
vi. Unscheduled DNA Synthesis (UDS) Assay: Non-genotoxic.
3. Reproductive and developmental toxicity. Reproductive and
developmental toxicity. Chlorfenapyr is neither a reproductive nor
developmental toxicant and is not a teratogenic agent in the Sprague-
Dawley rat or the New Zealand white rabbit. This is demonstrated by the
results of the following studies:
i. Rat oral teratology. No observed effect level (NOEL) for
maternal toxicity 25 mg/kg bwt/day and NOEL for fetal/developmental
toxicity at 225 mg/kg bwt/day.
ii. Rabbit oral teratology. NOEL for maternal 5 mg/kg bwt/day and
NOEL for fetal/developmental toxicity 30 mg/kg bwt/day.
iii. Rat 2-generation reproduction. NOEL for parental toxicity/
growth and offspring development 60 parts per million (ppm) (5 mg/kg
bwt/day) and NOEL for reproductive performance 600 ppm (44 mg/kg bwt/
day)
4. Subchronic toxicity. The following are the results of the
subchronic toxicity test that have been conducted with chlorfenapyr.
i. 28-Day rabbit dermal - NOEL 100 mg/kg bwt/day.
ii. 28-Day rat feeding - NOEL <600 ppm (<71.6 mg/kg bwt/day).
iii. 28-Day mouse feeding - NOEL <160 ppm (<32 mg/kg bwt/day).
iv. 13-Week rat dietary - NOEL 150 ppm (11.7 mg/kg bwt/day).
v. 13-Week mouse dietary - NOEL 40 ppm (8.2 mg/kg bwt/day).
vi. 13-Week dog dietary - NOEL 120 ppm (4.2 mg/kg bwt/day).
5. Chronic toxicity. Chlorfenapyr is not oncogenic in either
Sprague-Dawley rats or CD-1 mice and is not likely to be carcinogenic
in humans. The following are the results of the chronic toxicity tests
that have been conducted with chlorfenapyr:
[[Page 42025]]
i. 1-Year neurotoxicity in rats. No observed adverse effect level
(NOAEL) 60 ppm (2.6/3.4 mg/kg bwt/day M/F).
ii. 1-Year dog dietary. NOAEL 120 ppm (4.0/4.5 mg/kg bwt/day M/F).
iii. 24-Month rat dietary. NOAEL for chronic effects 60 ppm (2.9/
3.6 mg/kg bwt/day M/F and NOAEL for oncogenic effects 600 ppm (31/37
mg/kg bwt/day M/F).
iv. 18-Month mouse dietary - NOAEL for chronic effects 20 ppm (2.8/
3.7 mg/kg bwt/day M/F and NOEL for Oncogenic Effects 240 ppm (34.5/44.5
mg/kg bwt/day M/F).
6. Animal metabolism. A metabolism study was conducted in Sprague-
Dawley rats at approximately 20 and 200 mg/kg bwt using radiolabeled
chlorfenapyr. Approximately 65% of the administered dose was eliminated
during the first 24 hours (62% in feces and 3% in urine) and by 48
hours following dosing, approximately 85% of the dose had been excreted
(80% in feces and 5% in urine.) The absorbed chlorfenapyr-related
residues were distributed throughout the body and detected in tissues
and organs of all treatment groups. The principal route of elimination
was via feces, mainly as unchanged parent plus minor N-dealkylated,
debrominated, and hydroxylated oxidation products. The metabolic
pathway of chlorfenapyr in the laying hen and the lactating goat was
also similar to that in laboratory rats.
7. Metabolite toxicology. The parent molecule is the only moiety of
toxicological significance in plant and animal commodities.
8. Endocrine disruption. Collective organ weights and
histopathological findings from the 2-generation rat reproduction
study, as well as from the subchronic and chronic toxicity studies in
two or more animal species, demonstrate no apparent estrogenic effects
or effects on the endocrine system. There is no information available
which suggests that chlorfenapyr would be associated with endocrine
effects.
C. Aggregate Exposure
1. Dietary exposure. Based on the completeness and reliability of
the toxicity data and the exposure assessment conducted, BASF concludes
that there is a reasonable certainty that no harm will result from
aggregate exposure to chlorfenapyr, including all dietary exposure.
i. Food. There are currently no established U.S. permanent food
tolerances for chlorfenapyr. There are two tolerance petitions pending
at EPA; 0.5 ppm tolerance on imported citrus and 1.5 ppm tolerance on
greenhouse grown vegetable, fruiting, crop group 8. A dietary exposure
estimate based on theoretical maximum residue contribution (TMRC) was
conducted using the Dietary Exposure Evaluation Model
(DEEMTM) The TMRC is a ``worst case'' estimate for dietary
exposure because it assumes that 100% of crop is treated and residues
in the food are always found at the tolerance level. Additional
assumptions used were all consumption of tomatoes-whole is from treated
greenhouse grown tomatoes, greenhouse grown tomatoes are not processed,
and all citrus juice in the U.S. is made from treated imported citrus
pulp. Default processing factors were used to determine concentrations
in processed fractions. The tolerance levels used in the dietary
assessment were 0.5 ppm for citrus pulp, 1.5 ppm for vegetable,
fruiting, group 8, and 0.01 ppm for all other crops.
a. Acute exposure. The acute RfD used for this evaluation was 0.45
mg/kg bwt calculated by applying the 100-fold safety factor to the NOEL
from the acute neurotoxicity evaluation of chlorfenapyr. The acute
exposure was evaluated at the 99.9th percentile. The most
highly exposure sub-population was non-nursing infants (<1 yr old)
which utilized 16.2% of the acute RfD. Therefore, based on the exposure
assessment discussed above, BASF concludes there is a reasonable
certainty that no harm will result from the acute dietary exposure to
chlorfenapyr residues.
b. Chronic exposure. The chronic RfD used for this evaluation was
0.03 mg/kg bwt calculated by applying a 100-fold safety factor to the
NOAEL from 1-year rat neurotoxicity study and the chronic feeding
studies in the rat and mouse. The most highly exposure subpopulation
was children 1-6 years of age which utilized 19.8% of the chronic RfD.
Therefore, based on the exposure assessment discussed above, BASF
concludes there is a reasonable certainty that no harm will result from
the chronic dietary exposure to chlorfenapyr residues.
ii. Drinking water. There is no concern for exposure to residues of
chlorfenapyr in drinking water based on the approved, pending and
proposed directions for use and its physical and chemical properties.
Approved uses in the U.S. include applications to ornamental plants
inside greenhouses, to a narrow band of soil adjacent to buildings and
to crack-and-crevice and spot treatments inside structures. A pending
use expands greenhouse applications to vegetable, fruiting, crop group
8. The proposed use for food handling areas is also applied as a crack-
and-crevice and spot treatment inside structures. Chlorfenapyr has
extremely low water solubility (120 ppb at 25 [deg]C)and is also
immobile in soil and does not leach because it is strongly adsorbed to
all common soil types.
2. Non-dietary exposure. Non-dietary exposure to chlorfenapyr is
expected to be negligible based on assessments made by EPA for the
approved use on ornamentals grown in greenhouses, as a termiticide and
for indoor applications for general pest control. These assessments
were based on the physico-chemical characteristics of the compound, the
intended use pattern, and available information concerning its
environmental fate. The vapor pressure of chlorfenapyr is less than 1 x
10-7 mm of mercury (Hg); therefore, the potential for non-
occupational exposure by inhalation is insignificant. These assessments
also apply to the pending use on greenhouse grown vegetable, fruiting,
crop group 8 and the proposed use in food handling areas.
D. Cumulative Effects
The pyrrole insecticides represent a new class of chemistry with a
unique mechanism of action. No other data are available that indicate
that any toxicological effects produced by chlorfenapyr would be
cumulative with those of any other compound.
The parent molecule, chlorfenapyr is a pro-insecticide that is
converted to the active form, CL 303,268, via rapid metabolism by mixed
function oxidases (MFOs). The active form uncouples oxidative
phosphorylation in the insect mitochondria by disrupting the proton
gradient across the mitochondrial membrane. The production of ATP is
inhibited resulting in the cessation of all cellular functions. Because
of this unique mechanism of action, it is highly unlikely, that toxic
effects produced by chlorfenapyr would be cumulative with those of any
other pesticide chemical.
In mammals, there is a lower titer of MFOs, and chlorfenapyr is
metabolized by different pathways (including dehalogenation, oxidation
and ring hydroxylation) to other polar metabolites without any
significant accumulation of the potent uncoupler, CL 303,268. In the
rat, approximately 85% of the administered dose is excreted in the
feces within 48 hours, thereby reducing the levels of chlorfenapyr and
CL 303,268 that are capable of reaching the mitochondria. This
differential metabolism of chlorfenapyr to CL 303,268 in insects versus
to other polar metabolites in mammals is responsible for the selective
insect toxicity of the pyrroles.
[[Page 42026]]
E. Safety Determination
1. U.S. population. Using the exposure assumptions described above,
BASF has estimated that chronic dietary aggregate exposure to
chlorfenapyr for the U.S. population was 0.002615 mg/kg bwt/day or 8.7%
of the chronic RfD of 0.03 mg/kg bwt/day. Other than children less than
12 years of age, hispanics are the U.S. population subgroup with the
highest chronic exposure of 0.003403 mg/kg bwt/day, or 11.3% of the
RfD. EPA has no concerns about exposure that are less than 100% of the
RfD as the RfD represents the level at or below which daily aggregate
dietary exposure over a lifetime will not pose appreciable risks to
human health. It is therefore, safe to conclude that there is
reasonable certainty that no harm to the overall U.S. population will
result from chronic exposure to chlorfenapyr residues.
2. Infants and children. Using the exposure assumption described
above, BASF has estimated that the chronic dietary aggregate exposure
to chlorfenapyr for children 1-6 years of age was 0.005936 mg/kg bwt/
day, or 19.8% of the chronic RfD of 0.03 mg/kg bwt/day. Children 1-6
years of age were the sub-population that utilized the largest portion
of the chronic RfD. It is therefore, safe to conclude that there is
reasonable certainty that no harm to infants and children will result
from chronic exposure to chlorfenapyr residues.
F. International Tolerances
No Codex or Canadian tolerances/limits for residues in any food
presently exist for chlorfenapyr. In Mexico there is a MRL of 0.3 ppm
for cottonseed.
[FR Doc. 03-17900 Filed 7-15-03; 8:45 am]
BILLING CODE 6560-50-S