[Federal Register: December 22, 2004 (Volume 69, Number 245)]
[Notices]
[Page 76719-76724]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr22de04-44]
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ENVIRONMENTAL PROTECTION AGENCY
[OPP-2004-0399; FRL-7689-4]
Buprofezin; Notice of Filing an Amended Pesticide Petition to
Increase Tolerances 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 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-
2004-0399, must be received on or before January 21, 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: Richard J. Gebken, Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001; telephone number: (703) 305-6701; e-mail
address:gebken.richard@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 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
[[Page 76720]]
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. Docket. EPA has established an official public docket for this
action under docket ID number OPP-2004-0399. 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 athttp://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-2004-0399. 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-2004-0399. 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
[[Page 76721]]
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-2004-0399.
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-2004-0399. 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: December 9, 2004.
Lois Rossi,
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.
Nichino America, Inc.
PP 4F6873
EPA has received a petition (PP 4F6873) from Nichino America, Inc.,
4550 New Linden Hill Road, Suite 501, Wilmington, DE 19808 (the
registrant) by revising a previous pesticide petition (PP 0F6087) that
was submitted by Aventis Crop Science (formerly AgrEVO USA Co, that
published in the Federal Register of June 21, 2000 (65 FR 38543) (FRL-
6557-3). Nichino America, Inc. is proposing, pursuant to section 408(d)
of the FFDCA, 21 U.S.C. 346a(d), to amend 40 CFR 180.511 by
establishing increased tolerances for residues of buprofezin (2-tert-
butylimino-3-isopropyl-5-phenyl-1,3,5-thiadiazinan-4-one) in or on the
following raw agricultural commodities: Fruit, citrus, Group 10 at 2.5
parts per million (ppm), citrus, dried pulp at 7.5 ppm, and citrus, oil
at 80 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 metabolic profile of buprofezin has been
elucidated in a wide range of crops, including tomatoes, lettuce,
cotton, and citrus. In citrus, although buprofezin was a major
component of the residue, a chromatographically well-defined region of
radioactivity, clearly associated with polar conjugates, was observed.
Mass spectrometry identified the principal polar residue as a hexose
conjugate of BF4 (buprofezin hydroxylated in the t-butyl group).
Although the conjugate was resistant to enzyme hydrolysis, acid
hydrolysis of the polar fraction released predominantly BF26 with minor
amounts of BF9 and BF12. The same compounds were observed following
acid hydrolysis of a standard of BF4 clearly indicating that BF4 is the
conjugated metabolite existing in citrus. Although only limited
metabolism was observed in lettuce and cotton, trace levels of similar
metabolites, including the conjugate BF4 were observed indicating that
the metabolic pathway does not differ with plant species.
2. Analytical method. The proposed analytical method involves
extraction, partition, clean-up and detection of residues by gas
chromatography using nitrogen phosphorous detection.
3. Magnitude of residues. Nineteen field trials were conducted on
oranges with buprofezin, the principal residue of concern, in Regions
3, 6, and 10 at the maximum rate and minimum application and the
minimum preharvest interval (PHI) of 3 days. In addition, decline data
were generated that confirmed that residues of buprofezin decreased as
the PHI
[[Page 76722]]
increased from 1 to 30 days. The highest average residue value for
oranges treated with buprofezin (HAFT) at a 3-day PHI was 1.80 ppm.
Results from a previous processing study indicate that the
concentration in citrus oil was 42.7X and in citrus dried pulp 2.5X.
The requested tolerances are adequately supported.
B. Toxicological Profile
An extensive battery of toxicology studies has been conducted with
buprofezin. EPA has evaluated the available toxicity data and
considered its validity, completeness, and reliability as well as the
relationship of the results of the studies to human risk The nature of
the toxic effects caused by buprofezin is discussed in Unit III.A. of
the final rule on Buprofezin Pesticide Tolerance published in the
Federal Register on September 5, 2001 (66 FR 46381) (FRL-6796-6). An
assessment of toxic effects caused by buprofezin, including the
toxicological endpoints of concern, is also discussed in Unit III.A.
and Unit III.B. of the June 25, 2003 Federal Register (68 FR 37765)
(FRL-7310-7).
1. Animal metabolism. The metabolism of buprofezin has been
extensively studied in various species of animals and fish. Buprofezin
has several groups that can metabolize in a variety of ways thus
potentially producing a very large number of metabolites. Extensive
metabolism to many minor metabolites was observed in all the animal
species. Metabolism in fish was, however, much more limited and clearly
defined. Although not all metabolic intermediates have been detected in
all the species, the major routes of metabolism have been identified in
animals and fish and a consistent pattern is observed throughout these
species. The proposed metabolic pathway was provided in the tolerance
petition, PP 0F6087. For convenience, degradates are referred to by an
internal code: BF1 through 13. Corresponding chemical structures were
provided in the tolerance petition, PP 0F6087.
i. Metabolism in rats. The major metabolite found in rat excreta
was parent buprofezin in addition to several compounds formed after
extensive metabolism. Whereas plant metabolism appeared restricted
mainly to oxidation of the tertiary butyl group, oxidation of the butyl
group and hydroxylation of the phenyl ring were both observed in rats.
Oxidation of the t-butyl group proceeded beyond an alcohol to an acid
and was accompanied by ring opening. The most extensively metabolized
compound identified in rats was BF23 (acetylated p-aminophenol).
ii. Metabolism in ruminants and hens. Residue levels were low (0.05
ppm) in all ruminant and poultry tissues and commodities, following
treatment at exaggerated rates (approximately 20X and 7,500X the
anticipated dietary burden, respectively). The only exceptions were cow
liver (1.21 ppm), cow kidney (0.41 ppm), hen liver (0.15 ppm), and egg
yolk (0.11 ppm). Extensive metabolism was observed in both species with
a large number of minor metabolites being produced. The principal
metabolites identified in the cow were BF2 and BF23, indicating that
the major pathway of degradation in ruminants is hydroxylation of the
phenyl ring followed by opening and degradation of the heterocyclic
ring. The identification of trace levels of BF13 confirms this pathway.
As in rats, BF23 was the most extensively metabolized compound
identified. Trace levels of BF12 were also detected. This indicates
that the parallel pathway of heterocyclic ring opening without
hydroxylation of the phenyl ring is also in operation. Similarly in
hens, the identified metabolites were derived from degradation of the
heterocyclic ring either with (BF13) or without (BF9 and BF12) phenyl
ring hydroxylation. No single unidentified compound accounted for more
than 6% of the total residue in any animal tissue or commodity, with
the exception of a component comprising 8.7% of egg white. The total
residue in egg white was, however, only 0.02 ppm even at this highly
exaggerated dose rate.
iii. Metabolism in fish. Analysis of fish tissues, following a
bioaccumulation study, found a much simpler metabolic profile.
Buprofezin was present in both edible and non-edible tissues, but the
principle metabolites were polar conjugates of BF4. Trace levels of
BF12 were also detected.
2. Endocrine disruption. No special studies have been conducted to
investigate the potential of buprofezin to induce estrogenic or other
endocrine effects. The standard battery of required toxicity studies
has been completed. These studies include an evaluation of the
potential effects on reproduction and development and an evaluation of
the pathology of the endocrine organs following repeated or long-term
exposure. These studies are generally considered to be sufficient to
detect any endocrine effects. The only effect noted on endocrine organs
was an increased incidence of follicular cell hypertrophy and C-cell
hyperplasia of the thyroid gland in rats administered buprofezin.
Buprofezin also caused mild to moderate hepatotoxic effects at this
dietary concentration. The effect on the thyroid is consistent with an
increased turnover of T3/T4 in the liver with a resultant rise in TSH
secretion (due to the hepatotoxicity). The rat is known to be much more
susceptible than humans to these effects due to the very rapid turnover
of thyroxine in the blood in rats (12 hours vs. about 5 to 9 days in
humans). Therefore, the thyroid pathological changes which have been
noted following administration of high doses of buprofezin are
considered to be of minimal relevance to human risk assessment,
particularly considering the low levels of buprofezin to which humans
are likely to be exposed.
C. Aggregate Exposure
1. Dietary exposure. Acute and chronic dietary risk analyses were
conducted to estimate the potential buprofezin residues in/on the
following crops: Avocado, banana, canistel, cotton, grape, grape
raisin, longan, lychee, mango, papaya, mamey sapote, Spanish lime, head
lettuce, leaf lettuce, snap bean, tomato, curcurbit vegetables, citrus
oil, citrus orange, citrus grapefruit, citrus lemon, pome fruit,
apples, pome fruit pear, peach, almond, and pistachio using the Dietary
Exposure Evaluation Model (DEEM-FCID, ver. 1.30) software. Exposure
estimates to water were based on modeling and on percent crop treated.
2. Food. The acute dietary exposure was based on the following
assumptions: Residues at tolerance levels, 100% crop treated, and DEEM
(ver. 7.76) default processing factors for all registered/proposed
commodities (Tier 1). The Hazard Identification Assessment Review
Committee (HIARC) met on February 15, 2000, and determined the endpoint
selection for buprofezin (HED Doc. No. 014093) and subsequently on
October 22, 2002, to evaluate the potential for increased
susceptibility of infants and children from exposure to buprofezin.
Based on toxicological considerations, the special FQPA safety factor
was set at 1X when assessing acute and chronic dietary exposures. The
acute dietary aPAD (acute Population Adjusted Dose) was set at 2.0
milligrams/kilogram/day (mg/kg/day) for females aged 13-50 years old
based on a developmental toxicity study in rats that had an oral no
observed adverse effect level (NOAEL) of 200 mg/kg/day. The chronic
dietary cPAD (chronic Population Adjusted Dose) was determined to be
0.01 mg/kg/day for the general population based on a oral NOAEL of 1.0
mg/kg/day in the 2-year rat chronic/oncogenicity study. The
[[Page 76723]]
uncertainty factor of 100 was used to account for interspecies and
intraspecies variations. Since the only evidence of carcinogenicity was
``suggestive,'' this endpoint was not deemed relevant to this
assessment.
The resulting food exposure estimate for females 13-49 years old
was less than 5.4% of the Population Adjusted Dose (aPAD). No acute
endpoint was identified for the remaining population subgroups. The
chronic dietary exposure was based on the following assumptions:
Percent crop treated, average field trial residues at maximum label
rates, and minimum PHIs with no reduction factors for common washing,
cooking, or preparation practices. The food exposure estimates from
residues of buprofezin for the U.S. population was 38% of the cPAD. The
subpopulation with the highest exposure was children 1-2 years old with
< 81% of the cPAD used. These are considered conservative values.
3. Drinking water. The residue of concern in drinking water was
determined to be buprofezin. There are no established maximum
contaminant levels or health advisory levels for residues of buprofezin
in drinking water.
In the absence of comprehensive water monitoring data, the Agency
uses the FQPA Index Reservoir Screening Tool (FIRST) or the Pesticide
Root Zone Model/Exposure Analysis Modeling System (PRZM/EXAMS) to
produce estimates of pesticide concentrations in an index resevoir. The
Screen Concentrations in Groundwater (SCI-GROW) model is used to
predict pesticide concentrations in shallow ground water. For a
screening-level assessment for surface water, EPA will use FIRST (a
Tier 1 model) before using PRZM/EXAMS (a Tier 2 model). The FIRST model
is a subset of the PRZM/EXAMS model that uses a specific high-end
runoff scenario for pesticides. Both FIRST and PRZM/EXAMS incorporate
an index reservoir environment, and both models include a percent crop
area factor as an adjustment to account for the maximum percent crop
coverage within a watershed or drainage basin.
None of these models include consideration of the impact processing
(mixing, dilution, or treatment) of raw water for distribution as
drinking water would likely have on the removal of pesticides from the
source water. The primary use of these models by the Agency at this
stage is to provide a screen for sorting out pesticides for which it is
unlikely that drinking water concentrations would exceed human health
levels of concern.
The estimated drinking water concentrations (EDWCs) in surface
water were determined using the Tier II PRZM (Pesticide Root Zone
Model) and EXAMS (Exposure Analysis Modeling Stystem (PE4-PL, version
01). PRZM is used to simulate pesticide transport as a result of runoff
and erosion and spray drift from an agricultural field and EXAMS
estimates environmental fate and transport of pesticides in surface
water. The long-term average-estimated environmental concentrations
(EEC) was 3.5 parts per billion (ppb). The acute EDWCs are 19.2 ppb,
and for chronic 4.5 ppb. In ground water, using Tier I SCI-GROW, the
acute level is 0.1 ppb and chronic is 0.1 ppb.
4. Non-dietary exposure. The term residential exposure is used in
this document to refer to non-occupational, non-dietary exposure (e.g.,
for lawn and garden pest control, indoor pest control, termiticides,
and flea and tick control on pets). Buprofezin is not registered for
use on any sites that would result in residential exposure.
D. Cumulative Effects
A determination has not been made that buprofezin has a common
mechanism of toxicity with other substances. Buprofezin does not appear
to produce a common toxic metabolite with other substances. A
cumulative risk assessment was, therefore, not performed for this
analysis. Cumulative effects from substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when
considering whether to establish, modify, or revoke a tolerance, the
Agency consider ``available information'' concerning the cumulative
effects of a particular pesticide's residues and ``other substances
that have a common mechanism of toxicity.'' Unlike other pesticides for
which EPA has followed a cumulative risk approach based on a common
mechanism of toxicity, EPA has not made a common mechanism of toxicity
finding as to buprofezin and any other substances and buprofezin does
not appear to produce a toxic metabolite produced by other substances.
For the purposes of this tolerance action, therefore, EPA has not
assumed that buprofezin has a common mechanism of toxicity with other
substances. For information regarding EPA's efforts to determine which
chemicals have a common mechanism of toxicity and to evaluate the
cumulative effects of such chemicals, see the policy statements
released by EPA's OPP concerning common mechanism determinations and
procedures for cumulating effects from substances found to have a
common mechanism on EPA's web site at http://www.epa.gov/ pesticides/
cumulative/.
E. Safety Determination
1. U.S. population--i. Acute risk. Using the conservative
assumptions discussed above, based on the completeness and reliability
of the toxicity data, it is concluded that aggregate exposure to the
proposed uses of buprofezin will utilize at most 5.4% of the acute
reference dose of females (13-49 years) and is likely to be much less,
as more realistic data and models are developed. EPA generally has no
concern for exposures below 100% of the aPAD Drinking Water Levels of
Comparison (DWLOC) were calculated based on an aPAD of 2.0 mg/kg/day.
After calculating DWLOCs and comparing them to the EECs for surface
water and ground water, EPA does not expect the aggregate exposure to
exceed 100% of the aPAD.
ii. Chronic risk. Based on the toxicology data base and available
information on anticipated residues, the chronic dietary exposure to
the U.S. population (total) was estimated as 0.003769 mg/kg/day and was
38% of the estimated cPAD. Exposure to potential residues in drinking
water are expected to be negligible. Based on these assessments, it can
be concluded that there is reasonably certainty of no harm to the U.S.
population or any population subgroup from exposure to buprofezin.
2. Infants and children. Chronic exposure to children ages 1-2, the
highest exposed population subgroup, was 0.008116 mg/kg/day (81% of the
cPAD). Exposure to potential residues in drinking water is expected to
be negligible. EPA has determined that reliable data support using the
standard margin of exposure (MOE) and uncertainty factor (100 for
combined interspecies and intraspecies variability) for buprofezin and
that an additional safety factor of 10 is not necessary to be
protective of infants and children. EPA generally has no concern for
exposures below 100% of the cPAD. The acute EEC of 19 ppb is
considerably less than the DWLOC of 59,076 ppb. For the chronic
assessment, the children 1-2 years old subpopulation generated the
lowest chronic DWLOC of approximately 46 ppb. Thus, the chronic DWLOC
of 46 ppb is higher than the chronic EEC of 4.5 ppb. The Agency has
considered the potential aggregate exposure from food, water and non-
occupational exposure routes and has concluded aggregate exposure is
not expected to exceed 100% of the chronic reference dose, and
consequently, has determined there is a reasonable
[[Page 76724]]
certainty that no harm will occur to infants and children from
aggregate exposure to residues of buprofezin.
F. International Tolerances
Canada, Codex, and Mexico do not have maximum residue limits for
residues of buprofezin in/on the proposed crops. Therefore,
harmonization is not an issue.
[FR Doc. 04-27772 Filed 12-21-04; 8:45 am]
BILLING CODE 6560-50-S