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http://www.epa.gov/fedrgstr/EPA-PEST/2005/August/Day-24/p16807.htm

[Federal Register: August 24, 2005 (Volume 70, Number 163)]
[Notices]
[Page 49599-49607]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr24au05-52]
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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2005-0206; FRL-7726-3]

Fipronil; 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 identification (ID) number OPP-
2005-0206, must be received on or before September 23, 2005.
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 an
agricultural producer, food manufacturer, or pesticide manufacturer.
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
[[Page 49600]]
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. Docket. EPA has established an official public docket for this
action under docket ID number OPP-2005-0206. 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, 1801 S. Bell St., 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 in 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 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-2005-0206. 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-2005-0206. 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.

[[Page 49601]]

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-2005-0206.
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, 1801 S. Bell St., Arlington, VA, Attention: Docket ID
Number OPP-2005-0206. 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: August 15, 2005.
Donald R. Stubbs,
Acting 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 the petitioner 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 pesticide chemical residues or an explanation of why no such
method is needed.

BASF Corporation
5F6948 and 2E6490

EPA has received a pesticide petition (5F6948) from BASF
Corporation, P.O. Box 13528, Research Triangle Park, NC 27709
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 180.517 by
establishing a tolerance for residues of mixture comprising fipronil,
5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(1R,S)-
(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile and its
metabolites 5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-
[(trifluoromethyl) sulfonyl]-1H-pyrazole-3-carbonitrile and 5-amino-1-
[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)thio]-1H-
pyrazole-3-carbonitrile and its photodegradate 5-amino-1-[2,6-dichloro-
4-(trifluoromethyl)phenyl]-4-[(1R,S)-(trifluoromethyl)]-1H-pyrazole-3-
carbonitrile in or on the raw agricultural commodity corm vegetables
(crop group 1-C at 0.04 parts per million (ppm), and indirect and
inadvertent residues on wheat, grain at 0.005 and wheat, forage at 0.02
ppm and wheat, hay and straw at 0.03 ppm. EPA has received a pesticide
petition 2E6490 from The Interregional Research Project No. 4 (IR-4),
Technology Centre of New Jersey, Rutgers, the State University of New
Jersey, 681 U.S. Highway 1 South, North Brunswick, NJ 08902-3390
proposing, pursuant to section 408(d) of the FFDCA, 21 U.S.C. 346a(d),
to amend 40 CFR 180.517 by establishing a tolerance for residues of
mixture comprising fipronil, 5-amino-1-[2,6-dichloro-4-
(trifluoromethyl)phenyl]-4-[(1R,S)-trifluoromethyl)sulfinyl]-1H-
pyrazole-3-carbonitrile) and its metabolites 5-amino-1-[2,6-dichloro-4-
(trifluoromethyl)phenyl]-4-[(trifluoromethyl) sulfonyl]-1H-pyrazole-3-
carbonitrile and 5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-
[(trifluoromethyl)thio]-H-pyrazole-3-carbonitrile and its
photodegradate 5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-
[(1R,S)-(trifluoromethyl)]-1H-pyrazole-3-carbonitrile in or on the raw
agricultural commodities onion (dry bulb), garlic, shallot (dry bulb)
at 0.02 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 supports granting of
the petition. Additional data may be needed before EPA rules on the
petition.

A. Residue Chemistry

1. Plant metabolism. The metabolism of fipronil is adequately
understood. Adequate data on the nature of the residues in both plant
and animals, including identification of major

[[Page 49602]]

metabolites and degradates of fipronil, are available. In plants and
animal the metabolism of fipronil proceeds via oxidation of the
sulfoxide to yield sulfone and hydrolysis of nitrile to yield the
amide. Fipronil and its sulfone and amide constitute greater than 75%
of the identified residues in all studies. A limited amount of
reduction of sulfoxide to yield the sulfide occurs in some cases.
Further transformation of primary metabolites affords minor amounts of
carboxylic acid, the amide and the 4-protopyrazole.

2. Analytical method. Validated analytical methods are available
for detecting and measuring levels of fipronil and its metabolites in
onion, dry bulb, potato (corm vegetables) and its processing fractions
and wheat grain, forage, hay, and straw. The Method utilizes Capillary
Gas Chromatography equipped with a Ni electron capture detector. The
Limit of Quantitation (LOQ) for all potato matrices is 0.003 ppm for
all analytes. The LOQ for onion is 0.005 for all analytes.

3. Magnitude of residues. Field trials were carried out in order to
determine the magnitude of residue in potato. Field trials were
conducted in the required regions. Field trials were carried out using
the maximum label rate of 0.1 lbs active ingredient (a.i.) per acre
applied in furrow followed by four sequential foliar applications at
0.05 lbs a.i. per acre. The results demonstrate that any residue
present would originate from the in-furrow not the foliar applications.
In addition a processing study was conducted on potatoes. Onion field
trials were conducted in the required regions. The application was by
seed treatment at 25 grams of active ingredient/kilogram (g a.i./Kg) of
seed. Twelve field trials were conducted where wheat was planted
following application to primary crops. Applications rates were 0.13
lbs a.i. per acre in-furrow for six corn trials and 0.2 lbs a.i. per
acre foliar for six cotton trials.

B. Toxicological Profile

1. Acute toxicity. For technical fipronil:

2. Genotoxicity. Fipronil was negative in both in vitro and in vivo
assays conducted to investigate gene mutations, DNA damage, and
chromosomal aberrations.

3. Reproductive and developmental toxicity. The developmental
toxicity NOELs in the rat and rabbit were 20 mg/kg/day (HDT) and 1 mg/
kg/day (HDT), respectively. Maternal toxicity was observed in the rat
at the HDT as evidenced by decreased body weight gain and food
efficiency. In the rabbit, the maternal toxicity NOAEL was less than
0.1 mg/kg/day, based on reduced body weight gain and food efficiency at
all dose levels tested. In a two-generation rat study, the NOEL for
parental (systemic) toxicity was 3 ppm (0.26 mg/kg/day for both sexes
combined), based on increased weight of the thyroid glands and liver in
males and females, decreased weight of the pituitary gland in females,
and an increased incidence of follicular epithelial hypertrophy in
females at 30 ppm. The NOEL for reproductive toxicity was 30 ppm (2.64
mg/kg/day for both sexes combined), based on clinical signs of toxicity
in pups, decreased litter size, decreased pup body weights, decreased
mating, decreased fertility index, reduced pre- and postnatal survival,
and delays in physical development at 300 ppm (26.03 and 28.40 mg/kg/
day for males and females, respectively).

In a developmental neurotoxicity study in the rat, the NOAEL for
maternal toxicity was 10 ppm (0.91 mg/kg/day), based on decreased body
weights and body weight gain at 200 ppm (HDT; 15 mg/kg/day).
Considerable maternal toxicity at the HDT prevented adequate
neurotoxicity evaluation of pups at this dose level. There was no
evidence of neurotoxicity at 10 ppm (0.91 mg/kg/day), which was the
NOAEL for developmental neurotoxicity. The NOAEL for general
developmental toxicity was 0.5 ppm (0.05 mg/kg/day), based on systemic
effects consisting of decreases in pup weights during lactation and
increases in time of preputial separation in males at 10 ppm.

4. Subchronic toxicity. The NOAEL for systemic toxicity in rat was
5 ppm (0.35 mg/kg/day for both sexes combined), based on alterations in
serum protein values and increased weight of the liver and thyroid at
30 ppm (1.93 and 2.28 mg/kg/day for males and females, respectively).
The NOAELs in the dog were 2 and 0.5 mg/kg/day for male and female,
respectively, based on clinical signs of toxicity in males at 10 mg/kg/
day and clinical signs of toxicity and decreased body weight gain in
females at 2 mg/kg/day. The NOAEL for mice was 10 ppm (1.27 and 1.72
mg/kg/day for males and females, respectively), based on a possible
decreased body weight gain at 25 ppm (3.2 and 4.53 mg/kg/day for males
and females, respectively). A repeated dose dermal study in the rabbit
had a systemic NOAEL of 5 mg/kg/day, based on decreased body weight
gain and food consumption at 10 mg/kg/day, and a dermal irritation NOEL
of 10.0 mg/kg/day (HDT).

In a subchronic neurotoxicity study in rats, the NOEL was 5 ppm
(0.301 and 0.351 mg/kg/day for males and females, respectively), based
on results of the functional observational battery (FOB) at 150 ppm
(8.89 and 10.8 mg/kg/day for males and females, respectively).

5. Chronic toxicity. The NOAEL for systemic toxicity in a 1-year
feeding study in the dog was 0.3 mg/kg/day in females and 1 mg/kg/day
in males,

[[Page 49603]]

based on clinical signs of neurotoxicity at 1 and 2 mg/kg/day in
females and males, respectively. The NOAEL for systemic toxicity in
mice was 0.5 ppm (0.06 mg/kg/day) based on decreased body weight gain,
decreased food conversion efficiency in males, increased liver weights,
and liver histopathology at 10 ppm (1.3 mg/kg/day). Fipronil was not
carcinogenic when administrated to mice at dose levels up to 60 ppm.
The NOAEL in a 2-year dietary study in the rat was 0.5 ppm (0.019 and
0.025 mg/kg/day for males and females, respectively) based on clinical
signs of toxicity and alterations in clinical chemistry and thyroid
parameters at 1.5 ppm (0.059 and 0.078 mg/kg/day for males and females,
respectively). The EPA's Health Effects Division Carcinogenicity Peer
Review Committee classified fipronil in Group C - Possible Human
Carcinogen, based on thyroid tumors observed in rats at 300 ppm (HDT).
Mechanistic data indicate that these tumors are related to a disruption
in the thyroid-pituitary status and are specific to the rat. In
addition, there was no apparent concern for mutagenic activity. Thus,
it was recommended that RfD methodology, i.e. non-linear or threshold,
be used for the estimation of human risk.

6. Animal metabolism. The metabolism of fipronil is adequately
understood. Adequate data on the nature of residues in both plants and
animals, including identification of major metabolites and degradates
of fipronil, are available. In plants and animals the metabolism of
fipronil proceeds via oxidation of the sulfoxide to yield sulfone and
hydrolysis of nitrile to yield the amide. Fipronil and its sulfone and
amide constitute greater than 75% of the identified residues in all
studies. A limited amount of reduction of sulfoxide to yield the
sulfide occurs in some cases. Further transformation of the primary
metabolites affords minor amounts of the carboxylic acid, the amide and
the 4-protiopyrazole.

7. Metabolite toxicology. MB46513 photodegradate acute oral toxicity:

i. Acute neurotoxicity. The NOEL was 2 mg/kg, based on decreases in
body weight gain and food consumption in males and females during the
week following treatment, decreases in locomotor activity, hind-limb
splay and rectal temperature 6-hour post dosing in males and females,
and decreases in the proportion of males with an immediate righting
reflex on days 7 and 14, at 12 mg/kg/day.
In a rat developmental toxicity study, the NOEL was 1 mg/kg/day,
based on the slight increase in fetal and litter incidence of reduced
ossification of several bones at 2.5 mg/kg/day.

ii. Subchronic toxicity. The NOAEL in the rat was 3 ppm (0.18 and
0.21 mg/kg/day in males and females, respectively), based on clinical
signs of toxicity in both sexes and decreased body weight and body
weight gain in males at 10 ppm. The NOEL for the mouse was 0.5 ppm
(0.08 mg/kg/day), based on the aggressive and irritable behavior with
increased motor activity in males at 2 ppm. The NOEL for the dog was
9.5 ppm (0.29 mg/kg/day), based on behavioral changes in females at 35
ppm (1.05 mg/kg/day).
The rat chronic/carcinogenicity study was negative for
carcinogenicity. The LOAEL for females was 0.5 ppm (0.032 mg/kg/day),
based on clinical signs of toxicity. There was no NOEL established. For
males, the NOAEL was 2 ppm (0.098 mg/kg/day), based on clinical signs
of toxicity, and stomach and lung histopathology at 10 ppm (0.497 mg/
kg/day). No thyroid effects are observed in any of the rat, mouse or
dog studies with MB46513, supporting the conclusion that there is no
concern for cancer due to exposure to MB46513.

8. Endocrine disruption. Data from the reproduction/ developmental
toxicity and short- and long-term repeated dose toxicity studies with
fipronil in the rat, rabbit, mouse, or dog, do not suggest any
endocrine disruption activity. This information is based on the absence
of any treatment-related effects from the histopathological examination
of reproductive organs as well as the absence of possible effects on
fertility, reproductive performance, or any other aspect of
reproductive function, or on growth and development of the offspring.
Evidence of offspring toxicity was observed only in the presence of
significant parental toxicity. Fipronil disrupts the thyroid-pituitary
axis. However, mechanistic studies have demonstrated that fipronil
decreases thyroid hormone levels in long-term studies via increased
clearance, rather than a direct effect on the thyroid. Concerns related
to long-term exposure of fipronil are addressed in human risk
estimates, as the chronic RfD (0.0002 mg/kg/day) is based on endpoints
that include thyroid hormone related effects in rats.

C. Aggregate Exposure
1. Dietary exposure. An assessment was conducted to determine the
acute and chronic exposure of all population sub-groups to residues of
fipronil. Tolerance values have previously been established and are
listed in 40 CFR 180.517.
This analysis included all crops with established tolerance values
and the proposed new crops of white potato, sweet potato, onion bulb,
garlic, shallot bulb and the inadvertent residue tolerance on wheat
grain. The dietary exposure assessment for crops with established
tolerances was conducted by the U.S. Environmental Protection Agency in
2001 (PP# 7F04832. Fipronil in/on Cotton. HED Risk Assessment.
Barcode D248827; PC Code 129121; Case 288765 ; submission S547814).
Using these dietary exposure values is conservative because the
registration for fipronil on cotton was withdrawn, and the dietary
exposure assessment conducted by HED included all currently registered
uses and the proposed cotton use. Using the HED exposure values is
conservative (overestimates actual exposure) because the cotton use and
all requested modifications to existing tolerances were included in the
dietary exposure assessment.
The dietary exposure assessment for white potato, sweet potato,
onion bulb, garlic, and shallot bulb were conducted using tolerance
level residues, default processing factors, and 100% crop treated
factors. These assumptions are conservative because it assumes all
commodities will be at tolerance level and 100% of the crop has been
treated with fipronil. The dietary exposure assessment for the
inadvertent residues in wheat grain was conducted using tolerance level
residues, default processing factors, and a 7% crop treatment factor.
The U.S. EPA used a 7% crop treatment factor for corn in the dietary
exposure assessment. The tolerance for wheat grain is from inadvertent
residues that would occur when wheat is planted following a fipronil
treatment of corn. Therefore, the 7% crop treatment factor applies to
wheat inadvertent residues.
The dietary exposure assessments were conducted using the Dietary
Exposure Evaluation Model software with Food Commodity Intake Database
(DEEM-FCID).
i. Food--a. Acute dietary exposure assessment. The acute population
adjusted dose (aPAD) used was 0.025 mg/kg bw/day. Using the exposure

[[Page 49604]]

assumptions discussed above, the maximum fipronil acute dietary
exposure from food is 11% aPAD. The results of the acute dietary
assessment are presented in Table 1.

b. Chronic dietary exposure assessment. The chronic population
adjusted dose (cPAD) used was 0.0002 mg/kg bw/day. Using the exposure
assumptions discussed above, the maximum fipronil chronic dietary
exposure from food is 56% cPAD. The results of the chronic dietary
assessment are presented in Table 2.

ii. Drinking water. The drinking water values used for comparison
to the DWLOC (Drinking Water Level of Comparison) can be calculated
from model estimates or actual monitoring data. When modeling was
conducted, the currently registered corn use resulted in the highest
predicted estimated water concentrations. If monitoring data is
available it can be used instead of model predictions. A drinking water
monitoring study for fipronil and relevant metabolites in surface water
from the corn growing regions has beenconducted (MRID 45526101).
Therefore, these actual measured drinking water values will be used in
the drinking water assessment. The ground water values model by the EPA
when the cotton use was examined will also be used for comparison.
Based on the tier I screening model SCI-GROW (screening concentration
in ground water), the acute ground water value will not exceed 0.061
ppb (0.032 [mu]g/L for fipronil, 0.012 [mu]g/L for MB46136, 0.016
[mu]g/L for MB46513, and 0.001 [mu]g/L for MB45950). This value of
0.061 ppb is also used for chronic ground water comparisons.
In the drinking water monitoring study, water samples were
collected from 12 municipal water treatment facilities. The water
treatment facilities were selected based on the source of water and the
previousdocumented use of fipronil in the watershed area. Raw and
finished water samples were collect at each water treatment site. The
samples were collected on regular intervals between April and August.
The water samples wereanalyzed for firponil and metabolites: MB45950,
MB46136, and MB46513. The LOQ for the method was 10 parts per trillion
(ppt) and the LOD was 4 ppt. No residues were detected in any of the
finished water samples and no confirmed fipronil-related residues were
found in any of the raw samples. This study showed that the use of
fipronil in corn production does not pose a risk to surface drinking
water.
a. Acute aggregate exposure and risk (food and water). The acute
dietary risk associated with the existing fipronil uses and the
proposed use of white and sweet potatoes does not exceed a level of
concern. The estimated exposure at the 95th percentile uses
< = 11% of the aPAD (Table 1). The surface water and ground water
estimated concentrations were used to compare to the DWLOC. The
estimated water concentrations are less than the calculated DWLOC
(Table 3). Therefore, it can be concluded with reasonable certainty
that residues of fipronil and metabolites in drinking water do not
contribute significantly to the acute aggregate human health risk.

[[Page 49605]]

b. Short- and intermediate-term aggregate exposure and risk (food,
water and residential exposure). Short- and intermediate-term aggregate
exposure takes into account residential exposure plus chronic exposure
from food and water. Aggregation of systemic oral, dermal and
inhalation exposure from the residential use is not appropriate due to
differences in the toxicity endpoints observed between oral
(neurotoxicity and alterations in clinical chemistry and thyroid
parameters), dermal (decrease in body weight gain and food consumption)
and inhalation (developmental effects including decreases in pup
weights during lactation and increases in time of preputial separation)
routes. Also, there is no significant post-application exposure to
adults. However, post-application exposure to children is included in
the exposure assessment.
Post-application exposure of children can occur from three
scenarios: (1) Incidental ingestion of fipronil pellets or granules;
(2) incidental ingestion of soil (hand to mouth) from fipronil treated
residential areas; and (3) incidental ingestion (hand to mouth) of
fipronil from treated pets. EPA's OPP Health Effects Division believes
that exposure from scenario 1 is episodic and is only a one time
occurrence and episodic exposure is not aggregated with food and water.
Exposure from scenario #3 (3 x 10-5 mg/kg/day) is
greater that scenario #2 (1.2 x 10-6 mg/kg/day) and
therefore this exposure will be aggregated with food and water exposure.
The short- and intermediate-term exposure risk assessment was only
determined for the most highly exposed subpopulation which is children
1-6 years old (Table 4). The target MOE for short- and intermediate-
term exposure risk assessment is 300 and therefore, the maximum
allowable exposure is 0.00033 mg/kg bw/day (LOAEL, 0.1/300 safety
factor). The short- and intermediate term MOE for children 1-6 years of
age is 707 which is greater than 300. Also, the calculated DWLOC is
greater than the predicted chronic surface and ground water
concentrations. Therefore, taking into account all registered uses and
the white and sweet potato uses, it can be concluded with reasonable
certainty that residues of fipronil and metabolites in drinking water
will not result in short- and intermediate-term aggregate human health
risks.

c. Chronic aggregate exposure and risk (food and water). The
chronic dietary risk associated with the existing fipronil uses and the
proposed use of white and sweet potatoes does not exceed a level of
concern. The estimated exposures for all subpopulations are < = 56% of
the cPAD (Table 2). The surface water and ground water estimated

[[Page 49606]]

concentrations were used to compare to the DWLOC. The estimated water
concentrations are less than the calculated DWLOC (Table 5). Therefore,
it can be concluded with reasonable certainty that residues of fipronil
and metabolites in drinking water do not contribute significantly to
the chronic aggregate human health risk.

2. Non-dietary exposure. The residential exposure for fipronil
products was assessed by the U.S. EPA in the cotton risk evaluation in
2001.
i. Pet products. The residential exposure for the Frontline[reg]
pet products was assessed. The residential exposure for the
Frontline[reg]
pet products was determined based on the following
submitted studies: (1) Dermal and Inhalation Exposure of Commercial Pet
Groomers During the Application of Frontline[reg]
Spray Treatment (MRID
#44433302), (2) Dermal Exposure of Commercial Pet Groomers
During the Application of Frontline[reg] and Top Spot[reg] (MRID
44433303), and four studies examining the dislodgeable residues of
fipronil following the spray and spot treatment application to dogs and
cats (MRID 4443330-09). Based on these studies, HED determined the
dermal and inhalation exposure for residential applicators were 3.0 x
10-3 mg/kg bw/day and 1.78 x 10-6 mg/kg bw/day,
respectively. The non-dietary, oral (hand to mouth) was estimated to be
no greater than 3.0 x 10-5 mg/kg bw/day. The post-
application dermal exposure for toddlers was estimated to be 1.0 x
10-3 mg/kg bw/day. The MOEs for all exposure scenarios
evaluated were greater than 1500.
ii. Fire ant products. The applicator exposure was determine using
the ``Draft Standard Operating Procedures for Residential Exposure''
(December 18, 1997). The greatest homeowner applicator exposure was
calculated from the application of the granular product with a drop
spreader. The average daily dose for dermal and inhalation
exposure were 6.0 x 10-4 mg/kg bw/day and 1.3 x
10-6 mg/kg bw/day, respectively. The MOEs for all exposure
scenarios were >= 8,000.
Post-application from the fire ant granular products can occur from
dermal exposure and ingestion of granules from treated soil and/or
ingestion of treated soil by children. Based on a submitted
dislodgeable foliar residue study (MRID 44506901), HED concluded that
fipronil cannot be dislodged from treated turf and post-application
exposure from turf will not occur. HED calculated exposure to children
from the ingestion of granules in the treated area to be 2.8 x
10-3 mg/kg bw/day which resulted in a MOE of 890. The post-
application exposure to children from ingestion of treated soil was
calculated to be 1.2 x 10-6 mg/kg bw/day which resulted in a
MOE of 83,000.
HED concluded that there are no risk concerns for fipronil from the
residential uses.

D. Cumulative Effects
Section 408(b)(2)(D)(v) requires that, when considering whether to
establish, modify, or revoke a tolerance, the Agency consider available
information concerning the cumulative effects of a particular
pesticide's residues and other substances that have a common mechanism
of toxicity.
The EPA is currently developing methodology to perform cumulative
risk assessments. At this time, there are no available data to
determine whether fipronil has a common mechanism of toxicity with
other substances or how to include this pesticide in a cumulative risk
assessment.

E. Safety Determination
1. U.S. population. Based on this risk assessment, BASF concludes
that there is a reasonable certainty that no harm will result to the
general population from the aggregate exposure to fipronil.
2. Infants and children. Based on this risk assessment, BASF
concludes that there is a reasonable certainty that no harm will result
to infants or children from the aggregate exposure to fipronil residues.

F. International Tolerances
The following maximum residue levels (MRLs) have been established
by the Codex Alimentarius Commission (CODEX) for fipronil residues on
the following plant commodities: banana, 0.005 mg/kg; barley 0.002 mg/
kg; cabbage, head, 0.02 mg/kg; flowerhead brassicas, 0.02 mg/kg; maize
0.01 mg/kg; maize fodder 0.1 mg/kg; maize forage 0.1; oats, 0.002 mg/
kg; potato 0.02 mg/kg; rice 0.01 mg/kg; rice, straw and fodder, dry,
0.2 mg/kg; rye 0.002 mg/kg; sugar beet 0.2 mg/kg; sugar beet leaves

[[Page 49607]]

or tops, 0.2 mg/kg; sunflower seed, 0.002 mg/kg; triticale, 0.002 mg/
kg; wheat 0.002 mg/kg.
The following maximum residue levels (MRLs) have been established
by the Codex Alimentarius Commission (CODEX) for fipronil residues on
the following animal commodities: cattle, kidney 0.02 mg/kg; cattle
liver 0.1 mg/kg; cattle meat 0.05 mg/kg; eggs 0.02 mg/kg; poultry meat
0.01 mg/kg; poultry, edible offal, 0.02 mg/kg.
[FR Doc. 05-16807 Filed 8-23-05; 8:45 am]
BILLING CODE 6560-50-S