Carboxin; Pesticide Tolerance

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

[Federal Register: June 12, 2002 (Volume 67, Number 113)]
[Rules and Regulations]
[Page 40211-40219]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12jn02-14]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-2002-0028; FRL-7180-6]

AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.

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SUMMARY: This regulation establishes a tolerance for combinedresidues
of carboxin (5,6-dihydro-2-methyl-N-phenyl-1,4-oxathiin-3-carboxamide)
and its metabolite 5,6-dihydro-3-carboxanilide-2-methyl-1,4-oxathiin-4-
oxide (calculated as carboxin) (from treatment of seed prior to
planting) in or on onion, dry bulb. Uniroyal Chemical Company, Inc.
requested this tolerance under the Federal Food, Drug, and Cosmetic
Act, as amended by the Food Quality Protection Act of 1996. In
addition, this regulatory action is part of the tolerance reassessment
requirements of section 408(q) of the Federal Food, Drug, and Cosmetic
Act (FFDCA) 21 U.S.C. 346a(q), as amended by the Food Quality
Protection Act (FQPA) of 1996. By law, EPA is required to reassess 66%
of the tolerances in existence on August 2, 1996, by August 2002, or
about 6,400 tolerances. This regulatory action will count for 47
reassessments toward the August 2002 deadline.

DATES: This regulation is effective June 12, 2002. Objections and
requests for hearings, identified by docket ID number
OPP-2002-0028, must be received on or before August 12,
2002.

ADDRESSES: Written objections and hearing requests may be submitted by
mail, in person, or by courier. Please follow the detailed instructions
for each method as provided in Unit VI. of theSUPPLEMENTARY
INFORMATION. To ensure proper receipt by EPA, your objections and
hearing requests must identify docket ID number
OPP-2002-0028 in the subject line on the first page of your
response.

FOR FURTHER INFORMATION CONTACT: By mail: Mary L. Waller, Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460;
telephone number: (703) 308-9354; e-mail address:
waller.mary@epa.gov.

[[Page 40212]]

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

You may be affected by this action if you are an agricultural
producer, food manufacturer, or pesticide manufacturer. Potentially
affected categories and entities may include, but are not limited to:

------------------------------------------------------------------------
Examples of
Categories NAICS codes potentially
affected entities
------------------------------------------------------------------------
Industry 111 Crop production
112 Animal production
311 Food manufacturing
32532 Pesticide
manufacturing
------------------------------------------------------------------------

This listing is not intended to be exhaustive, but rather provides
a guide for readers regarding entities likely to be affected by this
action. Other types of entities not listed in the table could also be
affected. The North American Industrial Classification System (NAICS)
codes have been provided to assist you and others in determining
whether or not this action might apply to certain entities. If you have
questions regarding the applicability of this action to a particular
entity, consult the person listed under FOR FURTHER INFORMATION
CONTACT.

B. How Can I Get Additional Information, Including Copies of this
Document and Other Related Documents?

1. Electronically. You may obtain electronic copies of
thisdocument, and certain other related documents that might be
available electronically, from the EPA Internet Home Page at http://
www.epa.gov/. To access this document, on the Home Page select
"Laws and Regulations," "Regulations and Proposed
Rules," and then look up the entry for this document under the
"Federal Register Environmental Documents." You can
also go directly to the Federal Register listings at http://
www.epa.gov/fedrgstr/. A frequently updated electronic version of 40
CFR part 180 is available at http://www.access.gpo.gov/nara/cfr/cfrhtml_00/Title_40/40cfr180_00.html, a beta site
currently under development. To access the OPPTS Harmonized Guidelines
referenced in this document, go directly to the guidelines at http://
www.epa.gov/opptsfrs/home/guidelin.htm.
2. In person. The Agency has established an official record for
this action under docket ID number OPP-2002-0028. The
official record consists of the documents specifically referenced in
this action, and other information related to this action, including
any information claimed as Confidential Business Information (CBI).
This official record includes the documents that are physically located
in the docket, as well as the documents that are referenced in those
documents. The public version of the official record does not include
any information claimed as CBI. The public version of the official
record, which includes printed, paper versions of any electronic
comments submitted during an applicable comment period is available for
inspection in the Public Information and Records Integrity Branch
(PIRIB), Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy.,
Arlington, VA, from 8:30 a.m. to 4 p.m., Monday through Friday,
excluding legal holidays. The PIRIB telephone number is (703)
305-5805.

II. Background and Statutory Findings

In the Federal Register of March 29, 2000 (65 FR 16608)
(FRL-6493-8), EPA issued a notice pursuant to section 408
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a, as
amended by the Food Quality Protection Act of 1996 (FQPA) (Public Law
104-170), announcing the filing of a pesticide petition (PP
9F3727) by Uniroyal Chemical Company, Inc., 74 Amity Road, Bethany, CT.
This notice included a summary of the petition prepared by Gustafson
LLC, the registrant. No comments were received in response to the
notice of filing.
The petition requested that 40 CFR 180.301 be amended by
establishing atolerance for residues of the fungicide carboxin, 5,6-
dihydro-2-methyl-1,4-oxathiin-3-carboxanilide and its sulfoxide
metabolite 5,6-dihydro-3-carboxanilide-2-methyl-1,4-oxathiin-4-oxide,
each expressed as the parent compound, in or on onions (dry bulb) at
0.2 part per million (ppm).
Section 408(b)(2)(A)(i) of the FFDCA allows EPA to establish a
tolerance (the legal limit for a pesticide chemical residue in or on a
food) only if EPA determines that the tolerance is "safe."
Section 408(b)(2)(A)(ii) defines "safe" to mean that
"there is a reasonable certainty that no harm will result from
aggregate exposure to the pesticide chemical residue, including all
anticipated dietary exposures and all other exposures for which there
is reliable information." This includes exposure through drinking
water and in residential settings, but does not include occupational
exposure. Section 408(b)(2)(C) requires EPA to give special
consideration to exposure of infants and children to the pesticide
chemical residue in establishing a tolerance and to "ensure that
there is a reasonable certainty that no harm will result to infants and
children from aggregate exposure to the pesticide chemical residue. . .
."
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 and a complete description of
the risk assessment process, see the final rule on Bifenthrin Pesticide
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).

III. Aggregate Risk Assessment and Determination of Safety

Consistent with section 408(b)(2)(D), EPA has reviewed the
available scientific data and other relevant information in support of
this action. EPA has sufficient data to assess the hazards of and to
make a determination on aggregate exposure, consistent with section
408(b)(2), for tolerances for combined residues of carboxin (5,6-
dihydro-2-methyl-N-phenyl-1,4-oxathiin-3-carboxamide) and its
metabolite 5,6-dihydro-3-carboxanilide-2-methyl-1,4-oxathiin-4-oxide
(calculated as carboxin) (from treatment of seed prior to planting) on
onion, dry bulb at 0.2 ppm. EPA's assessment of exposures and risks
associated with establishing the tolerance follows.

A. Toxicological Profile

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. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and
children. The nature of the toxic effects caused by carboxin are
discussed in the following Table 1 as well as the no observed adverse
effect level (NOAEL) and the lowest observed adverse effect level
(LOAEL) from the toxicity studies reviewed.

[[Page 40213]]

Table 1. Subchronic, Chronic, and Other Toxicity Data
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Guideline No. Study Type Results
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870.3100 90-Day oral NOAEL = Males: not identified; Females: 10
toxicity in rats mg/kg/day
LOAEL = Males: 10 mg/kg/day based on
chronic nephritis,increased urea
nitrogen, increased creatinine; Females:
40 mg/kg/day based on chronic nephritis.
----------------------------------------------------------------------------------------------------------------
870.3200 21/28-Day dermal toxicity Not available
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870.3465 90-Day inhalation Not available
toxicity
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870.3700 Prenatal developmental in Maternal
rats NOAEL = 10 mg/kg/day......................
LOAEL = 90 mg/kg/day based on decreased
body weights andbody weight gain,
decreased food consumption, and
increasedhair loss.
Developmental.............................
NOAEL = 175 mg/kg/day....................
LOAEL = not identified....................
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870.3700 Prenatal developmental in Maternal
rabbits NOAEL = 75 mg/kg/day......................
LOAEL = 375 mg/kg/day based on increased
abortions.
Developmental.............................
NOAEL = 75 mg/kg/day......................
LOAEL = 375 mg/kg/day based on increased
abortions.
----------------------------------------------------------------------------------------------------------------
870.3800 Reproduction and Parental
fertility effects in NOAEL = Males and Females: 1 mg/kg/day....
rats LOAEL = Males: 10 mg/kg/day based on
decreased bodyweight gains in F₁ parents,
gross and histopathological changesin
kidneys; Females: 15 mg/kg/day based on
equivocal histopathological changes in
kidneys.
Reproductive..............................
NOAEL = Males: 10 mg/kg/day; Females: 15mg/
kg/day.
LOAEL = Males: 20 mg/kg/day; Females: 30
mg/kg/day basedon decreased fertility
indices for F_1b parents due to decreased
number of pregnancies for F_2b generation.
Offspring.................................
NOAEL = Males: 10 mg/kg/day; Females: 15
mg/kg/day.
LOAEL = Males: 20 mg/kg/day; Females: 30
mg/kg/day based on decreased body weights
for F_2b male pups.
----------------------------------------------------------------------------------------------------------------
870.4100 Chronic toxicity in dogs NOAEL = Males: 16 mg/kg/day; Females: 1.3
mg/kg/day
LOAEL = Males: 158 mg/kg/day based on
decreased RBC,hematocrit and hemoglobin,
increased MCH and MCV, increased alkaline
phosphatase and cholesterol, increased
liver weights; Females: 15 mg/kg/day
based on decreased body weight gains.
----------------------------------------------------------------------------------------------------------------
870.4200 Carcinogenicity in mice NOAEL = Males: 752 mg/kg/day; Females: 9
mg/kg/day
LOAEL = Males: not identified; Females:
451 mg/kg/day basedon increased mortality.
Negative for carcinogenicity..............
----------------------------------------------------------------------------------------------------------------
870.4300 Combined chronic/ NOAEL = Males: 0.8 mg/kg/day; Females: 1.0
carcinogenicity in rats mg/kg/day
LOAEL = Males: 9 mg/kg/day based on
decreased body weightand body weight
gain, increased urea nitrogen and
creatinine, increased water consumption
and urine volume, decreased urine
specific gravity, histopathological
changes in kidneys; Females: 16 mg/kg/day
based on histopathological changes in
kidneys.
Negative for carcinogenicity..............
----------------------------------------------------------------------------------------------------------------
870.5100 Bacterial reverse Negative with or without S-9 activation at
mutation assay (Ames 5,000 &mu;g/plate andless
test)
----------------------------------------------------------------------------------------------------------------
870.5375 In vitro mammalian Negative without S-9 activation
chromosome Positive with S-9 activation. Highly
aberration(CHO cells) significant increases inchromosomal
aberrations at several toxic dose levels
rangingfrom 400 to 1,400 &mu;g/mL..
----------------------------------------------------------------------------------------------------------------
870.5385 In vivo mammalian Negative at all dose levels up to 48-hours
chromosome aberration post-dosing
(ratbone marrow) Study is unacceptable due to lack of
clinical toxicity, lack of amultiple
dosing schedule, and/or lack of evidence
of transportto target tissue..
----------------------------------------------------------------------------------------------------------------
870.5385 In vivo mammalian Negative at all dose levels tested.
chromosome aberration
(ratbone marrow)
----------------------------------------------------------------------------------------------------------------

[[Page 40214]]

870.5385 In vivo mammalian Positive. Dose-related statistically
chromosome aberration significant increased percent of aberrant
(ratbone marrow) cells at &ge; 191 mg/kg/day.
----------------------------------------------------------------------------------------------------------------
870.5450 Dominant lethal assay in Not available
rats
----------------------------------------------------------------------------------------------------------------
870.5550 UDS in primary rat Positive. Dose-dependent positive
hepatocytes responses were observed at treatment
levels from 5.13 to 103 &mu;g/mL in the
absence of moderate to severe toxicity.
----------------------------------------------------------------------------------------------------------------
870.7485 Metabolism and Following oral treatment of rats with
pharmacokinetics in rats [phenyl-UL-C14]
carboxin, approximately
78.3-81.1% and 77.0-81.5% of the low and
high doses, respectively, were recovered.
Urine was the major route of excretion.
The major urinary metabolites were 4-
acetamidophenol and its glucuronide,
acetanilide, and hydroxylated carboxin
sulfoxide.
----------------------------------------------------------------------------------------------------------------

B. Toxicological Endpoints

The dose at which no adverse effects are observed (the NOAEL) from
the toxicology study identified as appropriate for use in risk
assessment is used to estimate the toxicological level of concern
(LOC). However, the lowest dose at which adverse effects of concern are
identified (the LOAEL) is sometimes used for risk assessment if no
NOAEL was achieved in the toxicology study selected. An uncertainty
factor (UF) is applied to reflect uncertainties inherent in the
extrapolation from laboratory animal data to humans and in the
variations in sensitivity among members of the human population as well
as other unknowns. An UF of 100 is routinely used, 10X to account for
interspecies differences and 10X for intraspecies differences.
For dietary risk assessment (other than cancer) the Agency uses the
UF to calculate an acute or chronic reference dose (acute RfD or
chronic RfD) where the RfD is equal to the NOAEL divided by the
appropriate UF (RfD = NOAEL/UF). Where an additional safety factor is
retained due to concerns unique to the FQPA, this additional factor is
applied to the RfD by dividing the RfD by such additional factor. The
acute or chronic Population Adjusted Dose (aPAD or cPAD) is a
modification of the RfD to accommodate this type of FQPA Safety Factor.
For non-dietary risk assessments (other than cancer) the UF is used
to determine the LOC. For example, when 100 is the appropriate UF (10X
to account for interspecies differences and 10X for intraspecies
differences) the LOC is 100. To estimate risk, a ratio of the NOAEL to
exposures (margin of exposure (MOE) = NOAEL/exposure) is calculated and
compared to the LOC.
The linear default risk methodology (Q*) is the primary method
currently used by the Agency to quantify carcinogenic risk. The Q*
approach assumes that any amount of exposure will lead to some degree
of cancer risk. A Q* is calculated and used to estimate risk which
represents a probability of occurrence of additional cancer cases
(e.g., risk is expressed as1 x 10-6 or one in a million).
Under certain specific circumstances, MOE calculations will be used for
the carcinogenic risk assessment. In this non-linear approach, a
"point of departure" is identified below which carcinogenic
effects are not expected. The point of departure is typically a NOAEL
based on an endpoint related to cancer effects though it may be a
different value derived from the dose response curve. To estimate risk,
a ratio of the point of departure to exposure (MOE_cancer =
point of departure/exposures) is calculated. A summary of the
toxicological endpoints for carboxin used for human risk assessment is
shown in the following Table 2:

Table 2. Summary of Toxicological Dose and Endpoints for Carboxin for Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
FQPA SF* and Level of
Exposure Scenario Dose Used in Risk Concern for Risk Study and Toxicological
Assessment, UF Assessment Effects
----------------------------------------------------------------------------------------------------------------
Acute dietary all populations Acute RfD = Not No toxicological None
required endpoint attributable
to a single
exposurewas identified
-----------------------------------------------------------------------------------------
Chronic dietaryall populations NOAEL= 0.8 mg/kg/day FQPA SF = 3 Combined chronic/
UF = 100............... cPAD = Chronic RfD/FQPA carcinogenicity - rat
Chronic RfD =0.008 mg/ SF= 0.00267 mg/kg/day. LOAEL = Males: 9 mg/kg/
kg/day. day based on decreased
body weightand body
weight gain, increased
urea nitrogen and
creatinine,increased
water consumption and
urine volume,
decreasedurine
specific gravity,
histopathological
changes inkidneys;
Females: 16 mg/kg/day
based on
histopathological
changes inkidneys
-----------------------------------------------------------------------------------------
Cancer (oral, Not likely to be Negative for Combined chronic/
dermal,inhalation) carcinogenic to humans carcinogenicity in carcinogenicity - rat
rats and mice andcarcinogenicity -
mouse
----------------------------------------------------------------------------------------------------------------
*The reference to the FQPA Safety Factor refers to any additional safety factor retained due to concerns unique
to the FQPA.

[[Page 40215]]

C. Exposure Assessment

1. Dietary exposure from food and feed uses. Tolerances havebeen
established (40 CFR 180.301) for the combined residues or residues of
carboxin and its sulfoxide metabolite, in or on a variety of raw
agricultural commodities. Risk assessments were conducted by EPA to
assess dietary exposures from carboxin and its sulfoxide metabolite in
food as follows:
i. Acute exposure. Acute dietary risk assessments are performed for
a food-use pesticide if a toxicological study has indicated the
possibility of an effect of concern occurring as a result of a 1 day or
single exposure. No toxicological endpoint attributable to a single
exposure was identified in the available toxicology studies on
carboxin. As a result, an acute endpoint was not identified and an
acute dietary exposure assessment was not performed.
ii. Chronic exposure. In conducting this chronic dietary
riskassessment, the Dietary Exposure Evaluation Model (DEEM)
analysisevaluated the individual food consumption as reported by
respondents in the USDA 1989-1992 nationwide Continuing Surveys
of Food Intake by Individuals (CSFII) and accumulated exposure to the
chemical for each commodity. The chronic dietary exposure analysis was
an unrefined assessment. Tolerance level residues and 100% crop treated
assumptions were used.
iii. Cancer. Carboxin was classified as "not likely to be
carcinogenic to humans." Therefore a cancer dietary exposure
assessment was not performed.
2. Dietary exposure from drinking water. The Agency lacks
sufficient monitoring exposure data to complete a comprehensive dietary
exposure analysis and risk assessment for carboxin and its sulfoxide
metabolite in drinking water. Because the Agency does not have
comprehensive monitoring data, drinking water concentration estimates
are made by reliance on simulation or modeling taking into account data
on the physical characteristics of carboxin and its sulfoxide
metabolite.
The Agency uses the First Index Reservoir Screening Tool (FIRST) or
thePesticide Root Zone/Exposure Analysis Modeling System (PRZM/EXAMS),
to produceestimates of pesticide concentrations in an index reservoir.
The Screening Concentrations in Ground Water (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. While both FIRST and PRZM/EXAMS
incorporate an index reservoirenvironment, the PRZM/EXAMS model
includes 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 coarse screen for sorting out pesticides for
which it is highly unlikely that drinking water concentrations would
ever exceed human health levels of concern.
Since the models used are considered to be screening tools in the
risk assessment process, the Agency does not use estimated
environmental concentrations (EECs) from these models to quantify
drinking water exposure and risk as a %RfD or %PAD. Instead drinking
water levels of comparisons (DWLOCs) are calculated and used as a point
of comparison against the model estimates of a pesticide's
concentration in water. DWLOCs are theoretical upper limits on a
pesticide's concentration in drinking water in light of total aggregate
exposure to a pesticide in food, and from residential uses. Since
DWLOCs address total aggregate exposure to carboxin and its sulfoxide
metabolite, they are further discussed in the aggregate risk sections
in Unit E.
Based on the FIRST and SCI-GROW models, the EECs of carboxin and
its sulfoxide metabolite for acute exposures are estimated to be 29.6
parts per billion (ppb) for surface water and 0.09 ppb for ground
water. The EECs for chronic exposures are estimated to be 0.63 ppb for
surface water and 0.09 ppb for ground water.
3. From 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). Carboxin
is not registered for use on any sites that would result in residential
exposure.
4. Cumulative exposure to substances with a common mechanism of
toxicity. 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."
EPA does not have, at this time, available data to determine
whether carboxin has a common mechanism of toxicity with other
substances or how to include this pesticide in a cumulative risk
assessment. Unlike other pesticides for which EPA has followed a
cumulative risk approach based on a common mechanism of toxicity,
carboxin 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 carboxin 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 final rule
for Bifenthrin Pesticide Tolerances (62 FR 62961, November 26, 1997).

D. Safety Factor for Infants and Children

1. In general. FFDCA section 408 provides that EPA shall apply an
additional tenfold margin of safety for infants and children in the
case of threshold effects to account for prenatal and postnatal
toxicity and the completeness of the data base on toxicity and exposure
unless EPA determines that a different margin of safety will be safe
for infants and children. Margins of safety are incorporated into EPA
risk assessments either directly through use of a margin of exposure
(MOE) analysis or through using uncertainty (safety) factors in
calculating a dose level that poses no appreciable risk to humans.
2. Prenatal and postnatal sensitivity. The developmentaltoxicity
and reproduction studies performed with carboxin did not indicate
evidence for enhanced susceptibility to the fetuses/offspring of rats
or rabbits. Neither quantitative nor qualitative increased
susceptibility was observed in the developmental toxicity study in
rats, the developmental toxicity study in rabbits, or the 2-generation
reproduction toxicity study in rats. In none of the toxicity studies on
carboxin was there any toxicologically significant evidence of
treatment-related neurotoxicity. A developmental neurotoxicity study in
rats is not required. There is, however, a concern for possible
germinal cell toxicity.
In genotoxicity studies, carboxin demonstrated clear evidence of
clastogenic potential. It was also noted

[[Page 40216]]

that in the 2-generation reproduction study in rats, treatment-related
decreased fertility indices for the F_1b male and female
parents (due to a decreased number of pregnancies for the
F_2b generation) were observed. Based on these
considerations, the registrant will be required to submit a germinal
cell assay, specifically a dominant lethal assay in rats, to the Agency
in order to evaluate possible interaction between carboxin and germinal
cell targets.
3. Conclusion. Based upon clear evidence of clastogenicactivity and
the requirement for a dominant lethal study, EPA concluded that a FQPA
safety factor of 3X is appropriate for this risk assessment. The safety
factor of 10X was reduced to 3X because: (1) There is no indication of
quantitative or qualitative increased susceptibility of rats or rabbits
toin utero and/or postnatal exposure; (2) a developmental neurotoxicity
study is not required; (3) the dietary (food and drinking water)
exposure assessments will not underestimate the potential for exposures
to infants and children; and (4) there are no registered residential
uses for carboxin.

E. Aggregate Risks and Determination of Safety

To estimate total aggregate exposure to a pesticide from food,
drinking water, and residential uses, the Agency calculates DWLOCs
which are used as a point of comparison against the model estimates of
a pesticide's concentration in water (EECs). DWLOC values are not
regulatory standards for drinking water. DWLOCs are theoretical upper
limits on a pesticide's concentration in drinking water in light of
total aggregate exposure to a pesticide in food and residential uses.
In calculating a DWLOC, the Agency determines how much of the
acceptable exposure (i.e., the PAD) is available for exposure through
drinking water (e.g., allowable chronic water exposure (mg/kg/day) =
cPAD - (average food + residential exposure)). This allowable exposure
through drinking water is used to calculate a DWLOC.
A DWLOC will vary depending on the toxic endpoint, drinking
waterconsumption, and body weights. Default body weights and
consumption values as used by the USEPA Office of Water are used to
calculate DWLOCs: 2L/70 kg (adult male), 2L/60 kg (adult female), and
1L/10 kg (child). Default body weights and drinking water consumption
values vary on an individual basis. This variation will be taken into
account in more refined screening-leveland quantitative drinking water
exposure assessments. Different populations will have different DWLOCs.
Generally, a DWLOC is calculated for each type of risk assessment used:
Acute, short-term, intermediate-term, chronic, and cancer.
When EECs for surface water and ground water are less than the
calculatedDWLOCs, EPA concludes with reasonable certainty that
exposures to the pesticide in drinking water (when considered along
with other sources of exposure for which EPA has reliable data) would
not result in unacceptable levels of aggregate human health risk at
this time. Because EPA considers the aggregate risk resulting from
multiple exposure pathways associated with apesticide's uses, levels of
comparison in drinking water may vary as those uses change. If new uses
are added in the future, EPA will reassess the potential impacts of
residues of the pesticide in drinking water as a part of the aggregate
risk assessment process.
1. Acute risk. No toxicological endpoint attributable to asingle
exposure was identified in the available toxicology studies on
carboxin. As a result, carboxin is not expected to pose an acute risk.
2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that exposure to carboxin
and its sulfoxide metabolite from food will utilize 41% of the cPAD for
the U.S. population and 92% of the cPAD for children 1-6 years, the
most highly exposed population. There are no residential uses for
carboxin. In addition, there is potential for chronic dietary exposure
to carboxin and its sulfoxide metabolite in drinking water. After
calculating DWLOCs and comparing them to the EECs for surface and
ground water, EPA does not expect the aggregate exposure to exceed 100%
of the cPAD, as shown in the following Table 3:

Table 3. Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Carboxin and its sulfoxide
metabolite
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup cPAD mg/kg/ %cPAD Water EEC Water EEC Chronic
day (Food) (ppb) (ppb) DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. populations 0.00267 41 0.63 0.09 56
---------------------------------------------------------------------------
Children 1-6 years 0.00267 92 0.63 0.09 2
----------------------------------------------------------------------------------------------------------------

3. Short-term and intermediate-term risk. Both short-term aggregate
exposure and intermediate-term aggregate exposure take into account
residential exposure plus chronic exposure to food and water
(considered to be a background exposure level). Carboxin is not
registered for use on any sites that would result in residential
exposure. Therefore, the aggregate risk is the sum of the risk from
food and water, which do not exceed the Agency's level of concern as
described in Table 3 above.
4. Aggregate cancer risk for U.S. population. Carboxin was
classified as "not likely to be carcinogenic to humans."
Therefore, carboxin is not expected to pose a cancer risk.
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to the general population, and to infants and children from aggregate
exposure to residues of carboxin and its sulfoxide metabolite.

IV. Other Considerations

A. Endocrine Disruptor Effects

FQPA requires EPA to develop a screening program to determine
whether certain substances (including all pesticides and inerts or
inactive ingredients) "may have an effect in humans that is
similar to an effect produced by a naturally occurring estrogen, or
such other endocrine effect. . . ." EPA has been working with
interested stakeholders to develop a screening and testing program as
well as a priority setting scheme. In the available toxicity studies
for carboxin, there is no evidence of endocrine disruptor effects. When
appropriate screening and/or testing protocols being considered under
the Agency's Endocrine Disruptor Screening Program have beendeveloped,
carboxin may be subjected to further screening and/or testing to better
characterize effects related to endocrine disruption.

[[Page 40217]]

B. Analytical Enforcement Methodology

The current available enforcement methods for tolerances of the
combined residues of carboxin and its carboxin sulfoxide metabolite are
described in the Pesticide Analytical Manual (PAM) Vol. II. Method I is
a colorimetric method which is used for determination of residues in or
on corn, peanuts, rice, rice straw, sorghum, soybeans, eggs, meat, and
milk. Method II and its modification, Method A, are GLC methods which
are used for wheat, oats, barley, peanuts, peanut oil and meal,
sorghum, cottonseed, and cottonseed oil and meal. Adequate recovery
data were submitted to validate the methods used in the dry bulb onion
field trials. Onions were analyzed by a modified version of Method II
wherein carboxin and its metabolite are hydrolyzed to aniline, which
was determined by GC/ECD.
Adequate enforcement methodology is available to enforce the
tolerance expression. The method may be requested from: Francis
Griffith, Analytical Chemistry Branch, Environmental Science Center,
U.S. Environmental Protection Agency, 701 Mapes Road, Fort George G.
Meade, MD 20755-5350; telephone number: (410) 305-2905; e-
mail address: griffith.francis@epa.gov.

C. International Residue Limits

There are no CODEX, Canadian, or Mexican maximum residue levels for
carboxin in/on onion seed. As a result, harmonization of tolerances is
not an issue.

D. Conditions

Submission of a dominant lethal assay in rats will be required as a
condition of registration due to the evidence of clastogenic potential
for carboxin and its potential effect on male germinal cells.

V. Conclusion

Therefore, the tolerance is established for combined residues of
carboxin,(5,6-dihydro-2-methyl-N-phenyl-1,4-oxathiin-3-carboxamide) and
its metabolite 5,6-dihydro-3-carboxanilide-2-methyl-1,4-oxathiin-4-
oxide (calculated as carboxin) (from treatment of seed prior to
planting) in or on onion, dry bulb at 0.2 ppm.

VI. Objections and Hearing Requests

Under section 408(g) of the FFDCA, as amended by the FQPA, any
person may file an objection to any aspect of this regulation and may
also request a hearing on those objections. The EPA procedural
regulations which govern the submission of objections and requests for
hearings appear in 40 CFR part 178. Although the procedures in those
regulations require some modification to reflect the amendments made to
the FFDCA by the FQPA of 1996, EPA will continue to use those
procedures, with appropriate adjustments, until the necessary
modifications can be made. The new section 408(g) provides essentially
the same process for persons to "object" to a regulation
for an exemption from the requirement of a tolerance issued by EPA
under new section 408(d), as was provided in the old FFDCA sections 408
and 409. However, the period for filing objections is now 60 days,
rather than 30 days.

A. What Do I Need to Do to File an Objection or Request a Hearing?

You must file your objection or request a hearing on this
regulation in accordance with the instructions provided in this unit
and in 40 CFR part 178. To ensure proper receipt by EPA, you must
identify docket ID number OPP-2002-0028 in the subject line
on the first page of your submission. All requests must be in writing,
and must be mailed or delivered to the Hearing Clerk on or before
August 12, 2002.
1. Filing the request. Your objection must specify the specific
provisions in the regulation that you object to, and the grounds for
the objections (40 CFR 178.25). If a hearing is requested, the
objections must include a statement of the factual issues(s) on which a
hearing is requested, the requestor's contentions on such issues, and a
summary of any evidence relied upon by the objector (40 CFR 178.27).
Information submitted in connection with an objection or hearing
request may be claimed confidential by marking any part or all of that
information as CBI. Information so marked will not be disclosed except
in accordance with procedures set forth in 40 CFR part 2. A copy of the
information that does not contain CBI must be submitted for inclusion
in the public record. Information not marked confidential may be
disclosed publicly by EPA without prior notice.
Mail your written request to: Office of the Hearing Clerk (1900),
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460. You may also deliver your request to the Office
of the Hearing Clerk in Rm. C400, Waterside Mall, 401 M St., SW.,
Washington, DC 20460. The Office of the Hearing Clerk is open from 8
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The
telephone number for the Office of the Hearing Clerk is (202)
260-4865.
2. Tolerance fee payment. If you file an objection or request a
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must
mail the fee to: EPA Headquarters Accounting Operations Branch, Office
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please
identify the fee submission by labeling it "Tolerance Petition
Fees."
EPA is authorized to waive any fee requirement "when in the
judgement of the Administrator such a waiver or refund is equitable and
not contrary to the purpose of this subsection." For additional
information regarding the waiver of these fees, you may contact James
Tompkins by phone at (703) 305-5697, by e-mail at
tompkins.jim@epa.gov, or by mailing a request for information to Mr.
Tompkins at Registration Division (7505C), Office of Pesticide
Programs, Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460.
If you would like to request a waiver of the tolerance objection
fees, you must mail your request for such a waiver to: James Hollins,
Information Resources and Services Division (7502C), Office of
Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania
Ave., NW., Washington, DC 20460.
3. Copies for the Docket. In addition to filing an objection or
hearing request with the Hearing Clerk as described in Unit VI.A., you
should also send a copy of your request to the PIRIB for its inclusion
in the official record that is described in Unit I.B.2. Mail your
copies, identified by docket ID number OPP-2002-0028, to:
Public Information and Records Integrity Branch, Information Resources
and Services Division (7502C), Office of Pesticide Programs,
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460. In person or by courier, bring a copy to the
location of the PIRIB described in Unit I.B.2. You may also send an
electronic copy of your request via e-mail to: opp-docket@epa.gov.
Please use an ASCII file format and avoid the use of special characters
and any form of encryption. Copies of electronic objections and hearing
requests will also be accepted on disks in WordPerfect 6.1/8.0 or ASCII
file format. Do not include any CBI in your electronic copy. You may
also submit an electronic copy of your request at many Federal
Depository Libraries.

B. When Will the Agency Grant a Request for a Hearing?

A request for a hearing will be granted if the Administrator
determines that the material submitted shows the following: There is a
genuine and substantial issue of fact; there is a reasonable
possibility

[[Page 40218]]

that available evidence identified by the requestor would, if
established resolve one or more of such issues in favor of the
requestor, taking into account uncontested claims or facts to the
contrary; and resolution of the factual issues(s) in the manner sought
by the requestor would be adequate to justify the action requested (40
CFR 178.32).

VII. Regulatory Assessment Requirements

This final rule establishes a tolerance under FFDCA section 408(d)
in response to a petition submitted to the Agency. The Office of
Management and Budget (OMB) has exempted these types of actions from
review under Executive Order 12866, entitled Regulatory Planning and
Review (58 FR 51735, October 4, 1993). Because this rule has been
exempted from review under Executive Order 12866 due to its lack of
significance, this rule is not subject to Executive Order 13211,
Actions Concerning Regulations That Significantly Affect Energy Supply,
Distribution, or Use (66 FR 28355, May 22, 2001). This final rule does
not contain any information collections subject to OMB approval under
the Paperwork Reduction Act (PRA), 44 U.S.C. 3501 et seq., or impose
any enforceable duty or contain any unfunded mandate as described under
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA) (Public Law
104-4). Nor does it require any special considerations under
Executive Order 12898, entitled Federal Actions to Address
Environmental Justice in Minority Populations and Low-Income
Populations (59 FR 7629, February 16, 1994); or OMB review or any
Agency action under Executive Order 13045, entitled Protection of
Children from Environmental Health Risks and Safety Risks (62 FR 19885,
April 23, 1997). This action does not involve any technical standards
that would require Agency consideration of voluntary consensus
standards pursuant to section 12(d) of the National Technology Transfer
and Advancement Act of 1995 (NTTAA), Public Law 104-113, section
12(d) (15 U.S.C. 272 note). Since tolerances and exemptions that are
established on the basis of a petition under FFDCA section 408(d), such
as the tolerance in this final rule, do not require the issuance of a
proposed rule, the requirements of the Regulatory Flexibility Act (RFA)
(5 U.S.C. 601 et seq.) do not apply. In addition, the Agency has
determined that this action will not have a substantial direct effect
on States, on the relationship between the national government and the
States, or on the distribution of power and responsibilities among the
various levels of government, as specified in Executive Order 13132,
entitledFederalism (64 FR 43255, August 10, 1999). Executive Order
13132 requires EPA to develop an accountable process to ensure
"meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism
implications." "Policies that have federalism
implications" is defined in the Executive Order to include
regulations that have "substantial direct effects on the States,
on the relationship between the national government and the States, or
on the distribution of power and responsibilities among the various
levels of government." This final rule directly regulates
growers, food processors, food handlers and food retailers, not States.
This action does not alter the relationships or distribution of power
and responsibilities established by Congress in the preemption
provisions of FFDCA section 408(n)(4). For these same reasons, the
Agency has determined that this rule does not have any "tribal
implications" as described in Executive Order 13175, entitled
Consultation and Coordination with Indian Tribal Governments (65 FR
67249, November 6, 2000). Executive Order 13175, requires EPA to
develop an accountable process to ensure "meaningful and timely
input by tribal officials in the development of regulatory policies
that have tribal implications." "Policies that have tribal
implications" is defined in the Executive Order to include
regulations that have "substantial direct effects on one or more
Indian tribes, on the relationship between the Federal Government and
the Indian tribes, or on the distribution of power and responsibilities
between the Federal Government and Indian tribes." This rule will
not have substantial direct effects on tribal governments, on the
relationship between the Federal Government and Indian tribes, or on
the distribution of power and responsibilities between the Federal
Government and Indian tribes, as specified in Executive Order 13175.
Thus, Executive Order 13175 does not apply to this rule.

VIII. Submission to Congress and the Comptroller General

The Congressional Review Act, 5 U.S.C. 801 et seq., as addedby the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and to the Comptroller General of the
United States. EPA will submit a report containing this rule and other
required information to theU.S. Senate, the U.S. House of
Representatives, and the Comptroller General of the United States prior
to publication of this final rule in the Federal Register. This final
rule is not a "major rule" as defined by 5 U.S.C. 804(2).

List of Subjects in 40 CFR Part 180

Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.

Dated: May 31, 2002.
Peter Caulkins,
Acting Director, Registration Division, Office of Pesticide Programs.

Therefore, 40 CFR chapter I is amended as follows:

PART 180 [AMENDED]

1. The authority citation for part 180 continues to read as
follows:

Authority: 21 U.S.C. 321(q), 346(a) and 374.

2. Section 180.301 is amended by alphabetically adding an entry for
the commodity "Onion, dry bulb" to the table in paragraph
(a); removing the text in paragraph (b); and reserving paragraph (b)
with a heading to read as follows:

Sec. 180.301 Carboxin; tolerances for residues.

(a) * * *

----------------------------------------------------------------------------------------------------------------
Commodity Parts per million
----------------------------------------------------------------------------------------------------------------
* * * * *
Onion, dry bulb....................................... 0.2
* * * * *
----------------------------------------------------------------------------------------------------------------

[[Page 40219]]

(b) Section 18 emergency exemptions. [Reserved]
* * * * *

[FR Doc. 02-14769 Filed 6-11-02; 8:45 am]
BILLING CODE 6560-50-S

Carboxin; Pesticide Tolerance

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