Thiamethoxam; Pesticide Tolerance

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

[Federal Register: January 5, 2005 (Volume 70, Number 3)]
[Rules and Regulations]
[Page 708-720]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr05ja05-17]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-2004-0394; FRL-7689-7]

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

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SUMMARY: This regulation establishes tolerances for combined residues
of thiamethoxam and its metabolite, (CGA-322704) in or on legume
vegetables, root vegetables (except sugar beet), strawberries,
bushberries, juneberries, lingonberries, salal, cranberries, spearmint,
peppermint, rapeseed, mustard, flax, safflower, crambe, borage, and
potatoes. In addition, the tolerance expression for tuberous and corm
vegetable crop subgroup (1C) is revised to a tolerance expression for
tuberous and corm crop subgroup (except potato) (1D). Syngenta Crop
Protection, Inc. and Interregional Research Project 4 requested this
tolerance under the Federal Food, Drug, and Cosmetic Act (FFDCA), as
amended by the Food Quality Protection Act of 1996 (FQPA).

DATES: This regulation is effective January 5, 2005. Objections and
requests for hearings must be received on or before March 7, 2005.

ADDRESSES: To submit a written objection or hearing request follow the
detailed instructions as provided in Unit VI. of the SUPPLEMENTARY
INFORMATION. EPA has established a docket for this action under Docket
identification (ID) number OPP-2004-0394. All documents in the docket
are listed in the EDOCKET index at http://www.epa.gov/edocket. Although
listed in the index, some information is not publicly available, i.e.,
CBI or other information whose disclosure is restricted by statute.
Certain other material, such as copyrighted material, is not placed on
the Internet and will be publicly available only in hard copy form.
Publicly available docket materials are available either electronically
in EDOCKET or in hard copy at the Public Information and Records
Integrity Branch (PIRIB), Rm. 119, Crystal Mall #2, 1801 South
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.

FOR FURTHER INFORMATION CONTACT: Dani Daniel, Registration Division
(7505C), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone
number: (703) 305-5409; e-mail address: daniel.dani@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), e.g., agricultural workers;
greenhouse, nursery, and floriculture workers; farmers.
? Animal production (NAICS 112), e.g., cattle ranchers and
farmers, dairy cattle farmers, livestock farmers.
? Food manufacturing (NAICS 311), e.g., agricultural
workers; farmers; greenhouse, nursery, and floriculture workers;
ranchers; pesticide applicators.
? Pesticide manufacturing (NAICS 32532), e.g., agricultural
workers; commercial applicators; farmers; greenhouse, nursery, and
floriculture workers; residential users.

[[Page 709]]

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

B. How Can I Access Electronic Copies of This Document and Other
Related Information?

In addition to using EDOCKET (http://www.regulations.gov/), you may
access this Federal Register document electronically through the EPA
Internet under the ``Federal Register'' listings at http://www.epa.gov/
fedrgstr/. A frequently updated electronic version of 40 CFR part 180
is available at E-CFR Beta Site Two at http://www.gpoaccess.gov/ecfr/.
To access the OPPTS Harmonized Guidelines referenced in this
document, go directly to the guidelines at
http://www.epa.gov/opptsfrs/home/guidelin.htm.

II. Background and Statutory Findings

In the Federal Register of June 2, 2004 (69 FR 31110) (FRL-7361-1),
EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C.
346a(d)(3), announcing the filing of pesticide petitions (PP 2E6363,
3E6781, 3E6800, 3E6805, 3E6806, 3E6807, 4E6819, and 0F6142) by Syngenta
Crop Protection, Inc., P.O. Box 18300 Greensboro, NC 27419-8300, and
Interregional Research Project 4 (IR-4), 681 US Highway 1 South, North
Brunswick, NJ 08902-3390. The petitions requested that 40 CFR 180.565
be amended by establishing tolerances for combined residues of the
insecticide thiamethoxam, 3-[(2-chloro-5-thiazolyl)methyl]tetrahydro-5-
methyl-N-nitro-4H-1,3,5-oxadiazin-4-imine and its metabolite CGA-322704
(N-(2-chloro-thiazol-5-ylmethyl)-N`-methyl-N'`-nitro-guanidine), in or
on legume vegetables group 6 at 0.02 parts per million (ppm) (3E6805),
peppermint and spearmint at 4.0 ppm (2E6363); root vegetables (except
sugar beet) crop subgroup 1B at 0.1 ppm and for radish tops at 0.80 ppm
(4E6819); strawberry at 0.30 ppm (3E6800); cranberry at 0.01 ppm
(3E6781); bushberry crop subgroup 13B and juneberry, lingonberry and
salal at 0.25 ppm (3E6807); rapeseed seed, mustard seed, flax seed,
safflower seed, crambe seed, and borage seed at 0.02 ppm (3E6806); and
potato at 0.25 ppm (0F6142). In addition, due to the establishment of
the individual tolerance for potato, it was requested that the
tolerance expression for tuberous and corm crop subgroup 1C be revised
to a tolerance expression for tuberous and corm (except potato) crop
subgroup 1D. That notice included a summary of these petitions prepared
by Syngenta Crop Protection, Inc. and IR-4, the registrant. As a result
of the residue data submitted to support these requests, the proposed
tolerance level for peppermint and spearmint was subsequently revised
to 1.5 ppm; the proposed tolerance level for root vegetables (except
sugar beet) crop subgroup 1B was subsequently revised to 0.02 ppm; the
proposed tolerance level for bushberry crop subgroup 13B and juneberry,
lingonberry and salal was subsequently revised to 0.20 ppm; and the
proposed tolerance for cranberry was revised to 0.02 ppm. There were no
comments received in response to the notice of filing.
Section 408(b)(2)(A)(i) of 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) of FFDCA 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) of FFDCA 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 of FFDCA 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) of FFDCA, 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) of FFDCA, for a tolerance for combined residues of
thiamethoxam and its metabolite CGA-322704 on legume vegetables group 6
at 0.02 ppm, peppermint and spearmint at 1.5 ppm; root vegetables
(except sugar beet) crop subgroup 1B at 0.02 ppm and for radish tops at
0.80 ppm; strawberry at 0.30 ppm; cranberry at 0.02 ppm; bushberry crop
subgroup 13B and juneberry, lingonberry and salal at 0.20 ppm; rapeseed
seed, mustard seed, flax seed, safflower seed, crambe seed, and borage
seed at 0.02 ppm; and potato at 0.25 ppm. In addition, due to the
establishment of the individual tolerance for potato, it was requested
that the tolerance expression for tuberous and corm crop subgroup 1C be
revised to a tolerance expression for tuberous and corm (except potato)
crop subgroup 1D. EPA's assessment of exposures and risks associated
with establishing the tolerance follows.
In assessing the human health risks associated with the existing
and proposed uses of thiamethoxam, EPA has included exposure to
thiamethoxam as well as its metabolite CGA-322704 when evaluating
exposure from the dietary (food only) pathway. This approach was
developed when the Agency received the first food-use request for
registration of thiamethoxam and determined that the CGA-322704
metabolite/degradate, as well as the parent compound, are residues of
concern in food; no exposure to CGA-322704 in drinking water was
considered likely following application of thiamethoxam. At the time,
toxicological information regarding CGA-322704 was not available, and
it was assumed that thiamethoxam and this metabolite are
toxicologically equivalent for estimation of dietary risk.
Subsequently, the Agency received a petition requesting registration of
the insecticide clothianidin. Upon review of that petition, the Agency
discovered that CGA-322704 and clothianidin are identical. With the
registration of clothianidin uses, the Agency has largely complete
toxicological databases for both thiamethoxam and CGA-322704 (referred
to in the remainder of this rule as clothianidin). While some of the
toxic effects observed following dosing with the two active ingredients
are similar, it is not clear that they are toxicologically equivalent.
To date, the Agency has not formally examined the toxicity data to
determine if it is appropriate to separate exposure to the parent
compound thiamethoxam

[[Page 710]]

from exposure to thiamethoxam's metabolite clothianidin when assessing
the aggregate risk associated with thiamethoxam tolerances. Therefore,
EPA has taken the very conservative approach of analzying the non-
cancer risk of thiamethoxam by both (1) aggregating exposure to
thiamethoxam and its metabolite clothianidin resulting from use of
thiamethoxam and clothianidin residues resulting from use of
clothianidin as an active ingredient and comparing this aggregate
exposure to relevant endpoints for thiamethoxam; and (2) aggregating
exposure to clothianidin resulting from thiamethoxam use and from use
of clothianidin as an active ingredient and comparing this aggregate
exposure to relevant endpoints for clothianidin. EPA has taken the
further conservative step of assuming that, in instances where both
thiamethoxam and clothianidin are registered for use on a crop, both
pesticides will, in fact, be used on that crop. Despite this very
conservative approach, thiamethoxam non-cancer risks (taking into
account clothianidin exposure) are well below the Agency's level of
concern (LOC).
Pending formal reconsideration of toxicological equivalency for
thiamethoxam and the clothianidin metabolite, aggregate risks from both
thiamethoxam and clothianidin are presented below.

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 thiamethoxam as
well as the no observed adverse effect level (NOAEL) and the lowest
observed adverse effect level (LOAEL) from the toxicity studies
reviewed are discussed in the Federal Register of September 17, 2003
(68 FR 54386) (FRL-7327-5). The nature of the toxic effects caused by
the metabolite clothianidin are discussed in the Federal Register of
May 30, 2003 (68 FR 32390) (FRL-7306-8).

B. Toxicological Endpoints

The dose at which the NOAEL from the toxicology study identified as
appropriate for use in risk assessment is used to estimate the
toxicological LOC. However, 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.
Three other types of safety or uncertainty factors may be used:
``Traditional uncertainty factors;'' the ``special FQPA safety
factor;'' and the ``default FQPA safety factor.'' By the term
``traditional uncertainty factor,'' EPA is referring to those
additional uncertainty factors used prior to FQPA passage to account
for database deficiencies. These traditional uncertainty factors have
been incorporated by the FQPA into the additional safety factor for the
protection of infants and children. The term ``special FQPA safety
factor'' refers to those safety factors that are deemed necessary for
the protection of infants and children primarily as a result of the
FQPA. The ``default FQPA safety factor'' is the additional 10X safety
factor that is mandated by the statute unless it is decided that there
are reliable data to choose a different additional factor (potentially
a traditional uncertainty factor or a special FQPA safety factor).
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 an UF of
100 to account for interspecies and intraspecies differences and any
traditional uncertainty factors deemed appropriate (RfD = NOAEL/UF).
Where a special FQPA safety factor or the default FQPA safety factor is
used, 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 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). An example of how such a probability risk is expressed
would be to describe the risk as one in one hundred thousand (1 x
10-\5\), one in a million (1 x 10-\6\), or one in
ten million (1 x 10-\7\). 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 thiamethoxam used for
human risk assessment is shown in Table 1 of this unit:

Table 1.--Summary of Toxicological Dose and Endpoints for Thiamethoxam for Use in Human Risk Assessment
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Dose Used in Risk FQPA SF and LOC for Study and Toxicological
Exposure Scenario Assessment, UF Risk Assessment Effects
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Acute dietary (general population NOAEL = 100 mg/kg/day FQPA SF = 10 Acute mammalian
including infants and children) UF = 100............... aPAD = acute RfD / FQPA neurotoxicity study in
Acute RfD = 1 mg/kg/day SF. the rat
= 0.1 mg/kg/day........ LOAEL = 500 mg/kg/day
based on treatment-
related
neurobehavioral
effects observed in
the FOB and LMA
testing (drooped
palpebral closure,
decreased rectal
temperature and
locomotor activity,
increased forelimb
grip strength)
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[[Page 711]]

Chronic dietary (all populations) NOAEL = 0.6 mg/kg/day FQPA SF = 10 2-Generation
UF = 100............... cPAD = chronic RfD / reproduction study
Chronic RfD = 0.006 mg/ FQPA SF. LOAEL = 1.8 mg/kg/day
kg/day. = 0.0006 mg/kg/day.... based on increased
incidence and severity
of tubular atrophy in
testes of F\1\
generation males.
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Oral nondietary (all durations) NOAEL = 0.6 mg/kg/day Residential LOC for MOE 2-Generation
= 1,000 reproduction study
LOAEL = 1.8 mg/kg/day
based on increased
incidence and severity
of tubular atrophy in
testes of F\1\
generation males.
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Dermal (all durations) Oral study Resdiential LOC for MOE 2-Generation
NOAEL = 0.6 mg/kg/day = 1,000 reproduction study
(dermal absorption LOAEL = 1.8 mg/kg/day
rate = 27%). based on increased
incidence and severity
of tubular atrophy in
testes of F\1\
generation males.
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Inhalation (all durations) Oral study NOAEL = 0.6 Residential LOC for MOE 2-Generation
mg/kg/day(inhalation = 1,000 reproduction study
absorption rate = LOAEL = 1.8 mg/kg/day
100%) based on increased
incidence and severity
of tubular atrophy in
testes of F\1\
generation males.
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Cancer (oral, dermal, inhalation) Likely carcinogen for humans based on increased incidence of
hepatocellular adenomas and carcinomas in male and female mice.
Quantification of risk based on most potent unit risk: Male mouse liver
adenoma and/or carcinoma combined tumor rate. The upper bound estimate
of unit risk, Q1* (mg/kg/day)\-\2 is 3.77 x 10\-\2 in human equivalents.
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A summary of the toxicological endpoints for the metabolite
clothianidin used for human risk assessment is shown in Table 2 of this
unit:

Table 2.--Summary of Toxicological Dose and Endpoints for Clothianidin for Use in Human Risk Assessment
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Dose Used in Risk
Assessment,
Exposure Scenario Interspecies and Special FQPA SF and LOC Study and Toxicological
Intraspecies and any for Risk Assessment Effects
Traditional UF
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Acute dietary (Females 13-50 years of Developmental NOAEL = FQPA SF = 1 Developmental rabbit
age) 25 mg/kg/day aPAD = acute RfD / FQPA study
UF = 1,000............. SF. Developmental LOAEL =
Acute RfD = 0.025 mg/kg = 0.025 mg/kg.......... 75 mg/kg/day based on
an increased litter
incidence of a missing
lobe of the lung.
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Acute dietary (General population) NOAEL = 25 mg/kg/day FQPA SF = 1 Special Neurotoxicity/
UF = 1,000............. aPAD = acute RfD / FQPA Pharmacology Study in
Acute RfD = 0.025 mg/kg SF. Mice and Rats
= 0.025 mg/kg.......... LOAEL = 50 mg/kg based
on transient signs of
decreased spontaneous
motor activity,
tremors and deep
respirations.
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Chronic dietary (All populations) Offspring NOAEL = 9.8 FQPA SF = 1 2-Generation
mg/kg/day cPAD = chronic RfD / Reproduction Study
UF = 1,000............. FQPA SF = 0.0098 mg/kg/ Offspring LOAEL = 31.2
Chronic RfD = 0.0098 mg/ day. mg/kg/day based on
kg/day. decreased mean body
weight gain and
delayed sexual
maturation, decreased
absolute thymus
weights in F\1\ pups
and an increase in
stillbirths in both
generations.
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Incidental Oral (All durations) NOAEL = 9.8 mg/kg/day Residential LOC for MOE 2-Generation
= 1,000 reproduction study
Offspring LOAEL = 31.2
mg/kg/day based on
decreased mean body
weight gain and
delayed sexual
maturation, decreased
absolute thymus
weights in F\1\ pups
and an increase in
stillbirths in both
generations.
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[[Page 712]]

Dermal (All durations) Oral study Residential LOC for MOE 2-Generation
NOAEL = 9.8 mg/kg/day = 1,000 reproduction study
(dermal absorption Offspring LOAEL = 31.2
rate = 1%). mg/kg/day based on
decreased mean body
weight gain and
delayed sexual
maturation, decreased
absolute thymus
weights in F\1\ pups
and an increase in
stillbirths in both
generations.
----------------------------------------------------------------
Inhalation (All durations) Oral study Residential LOC for MOE 2-Generation
NOAEL = 9.8 mg/kg/day = 1,000 reproduction study
(inhalation absorption Offspring LOAEL = 31.2
rate = 100%). mg/kg/day based on
decreased mean body
weight gain and
delayed sexual
maturation, decreased
absolute thymus
weights in F\1\ pups
and an increase in
stillbirths in both
generations.
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Cancer (oral, dermal, inhalation) Classification: Not likely to be carcinogenic to humans.
----------------------------------------------------------------------------------------------------------------

C. Exposure Assessment

1. Dietary exposure from food and feed uses. Tolerances have been
established (40 CFR 180.565) for the combined residues of thiamethoxam
and its metabolite clothianidin in or on a variety of raw agricultural
commodities. Tolerances for thiamethoxam are established on barley,
canola, cotton, sorghum, wheat, imported coffee, pecan, stone fruit,
succulent bean, sunflower, tuberous and corm vegetables crop subgroup,
fruiting vegetables, crop group, tomato paste, cucurbit vegetables crop
group, pome fruits crop group, field corn forage, field corn stover,
sweet corn stover, field corn grain, popcorn grain, sweet corn (kernal
and cob with husk removed), milk, and the meat and meat by products of
cattle, goats, horses, and sheep. Since clothianidin is a major
metabolite of thiamethoxam, residues of clothianidin that would
theoretically result from registered and pending uses of clothianidin
and residues that would theoretically result from the metabolism of
thiamethoxam are included in the analysis. Risk assessments were
conducted by EPA to assess dietary exposures from thiamethoxam 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. In conducting the acute dietary risk assessment EPA
used the Dietary Exposure Evaluation Model software with the Food
Commodity Intake Database (DEEM-FCID\TM\), which incorporates food
consumption data as reported by respondents in the United States
Department of Agriculture (USDA) 1994-1996 and 1998 Nationwide
Continuing Surveys of Food Intake by Individuals (CSFII), and
accumulated exposure to the chemical for each commodity. The following
assumptions were made for the acute exposure assessments: EPA conducted
the acute dietary exposure analysis based on highly conservative
assumptions. The residues of concern for the acute analysis are
thiamethoxam and its metabolite clothianidin. The assessment for
thiamethoxam assumed that 100% of the registered and proposed crops
were treated and that all treated crops and livestock had residues of
concern at the tolerance level. The general U.S. population and all
population subgroups have exposure and risk estimates which are below
EPA's LOC (i.e., the aPADs are all below 100%). The most highly exposed
subgroup is children 1 to 2 years of age. The exposure estimate for
children 1 to 2 years of age is 0.01099 mg/kg/day, which is equivalent
to 11% of the aPAD.
For the metabolite clothianidin, the acute analysis is a
conservative assessment that was based on tolerance level residues and
the assumption of 100 percent crop treated (PCT) for established and
proposed clothianidin uses. For the commodities that have both
thiamethoxam tolerances and established or proposed clothianidin
tolerances (i.e., sweet corn, field corn, pop corn, canola, milk, and
pome fruit), the proposed clothianidin tolerances are added to the
residues that could result from use of thiamethoxam. The general U.S.
population and all population subgroups have exposure and risk
estimates which are below EPA's LOC (i.e., the aPADs are all below
100%). The most highly exposed population subgroup is infants less than
1 year old, which utilizes 80% of the aPAD.
ii. Chronic exposure. In conducting the chronic dietary risk
assessment EPA used the DEEM-FCID\TM\, which incorporates food
consumption data as reported by respondents in the USDA 1994-1996 and
1998 Nationwide CSFII, and accumulated exposure to the chemical for
each commodity. The following assumptions were made for the chronic
exposure assessments: The residues of concern for the chronic analysis
are thiamethoxam and its metabolite clothianidin. The chronic analysis
for thiamethoxam was based on anticipated residues in the form of
average field trial residue values, and the analysis included percent
crop estimates. The general U.S. population and all population
subgroups have exposure and risk estimates which are below EPA's LOC
(i.e., the cPADs are all below 100%). The most highly exposed subgroup
is children 1 to 2 years of age. The exposure estimate for children 1
to 2 years of age is 0.000103 mg/kg/day, which is equivalent to 17% of
the cPAD.
For clothianidin, the chronic analysis is a relatively conservative
assessment that was based on tolerance level residues and the
assumption of 100% crop treated for established and proposed
clothianidin uses, with the exception of anticipated residues (AR) for
apples and pears. For the commodities that have both thiamethoxam
tolerances and established or proposed clothianidin tolerances (i.e.,
sweet corn, field corn, pop corn, canola, and milk), the

[[Page 713]]

proposed clothianidin tolerances are added to the residues that could
result from use of thiamethoxam. For apples and pears, the highest
average field trial (HAFT) levels from the residue field trials were
added to the residues that could result from use of thiamethoxam. The
general U.S. population and all population subgroups have exposure and
risk estimates which are below EPA's LOC (i.e., the cPADs are all below
100%). The most highly exposed population subgroup is children 1 to 2
years of age, which utilizes 15% of the cPAD.
iii. Cancer. The residue of concern for the cancer analysis is
thiamethoxam, per se. The residues of its metabolite clothianidin were
removed from the cancer analysis because the metabolite was found to be
``not likely to be carcinogenic to humans'' when it was evaluated as an
active ingredient. The cancer analysis was based on average field trial
residue values as well as PCT estimates. The estimated dietary exposure
to the U.S. population is 0.000263 mg/kg/day.
iv. Anticipated residue and PCT information. Section 408(b)(2)(E)
of the FFDCA authorizes EPA to use available data and information on
the anticipated residue levels of pesticide residues in food and the
actual levels of pesticide chemicals that have been measured in food.
If EPA relies on such information, EPA must pursuant to section
408(f)(1) require that data be provided 5 years after the tolerance is
established, modified, or left in effect, demonstrating that the levels
in food are not above the levels anticipated. Following the initial
data submission, EPA is authorized to require similar data on a time
frame it deems appropriate. For the present action, EPA will issue such
data call-ins for information relating to anticipated residues as are
required by FFDCA section 408(b)(2)(E) and authorized under FFDCA
section 408(f)(1). Such data call-ins will be required to be submitted
no later than 5 years from the date of issuance of this tolerance.
Section 408(b)(2)(F) of FFDCA states that the Agency may use data
on the actual percent of food treated for assessing chronic dietary
risk only if the Agency can make the following findings: Condition 1,
that the data used are reliable and provide a valid basis to show what
percentage of the food derived from such crop is likely to contain such
pesticide residue; Condition 2, that the exposure estimate does not
underestimate exposure for any significant subpopulation group; and
Condition 3, if data are available on pesticide use and food
consumption in a particular area, the exposure estimate does not
understate exposure for the population in such area. In addition, the
Agency must provide for periodic evaluation of any estimates used. To
provide for the periodic evaluation of the estimate of PCT as required
by section 408(b)(2)(F) of FFDCA, EPA may require registrants to submit
data on PCT.
The Agency used PCT information as follows:For existing uses, the
Agency used estimates of PCT for the chronic exposure assessment which
was determined using USDA's National Agricultural Statistics Service
(NASS) Usage Data (1999-2003) and EPA Proprietary Usage Data (2001-
2003). The chronic PCT estimates that were used for existing uses are
shown in Table 3:

Table 3.--Thiamethoxam Estimates of Crop Treated for Existing Uses
------------------------------------------------------------------------
Percent Crop
Commodity Treated
------------------------------------------------------------------------
Apples............................................... 5
------------------------------------------------------------------------
Barley............................................... 1
------------------------------------------------------------------------
Canola............................................... 55
------------------------------------------------------------------------
Cantaloupes.......................................... 13
------------------------------------------------------------------------
Casabas.............................................. 44
------------------------------------------------------------------------
Cottonseed........................................... 20
------------------------------------------------------------------------
Crabapples........................................... 20
------------------------------------------------------------------------
Cucumbers............................................ 5
------------------------------------------------------------------------
Field corn, grain.................................... 6
------------------------------------------------------------------------
Fruiting vegetables (except cucurbits - Crop group 8) 15
------------------------------------------------------------------------
Honeydew melons...................................... 13
------------------------------------------------------------------------
Loquats.............................................. 53
------------------------------------------------------------------------
Pears................................................ 9
------------------------------------------------------------------------
Popcorn.............................................. 6
------------------------------------------------------------------------
Potatoes............................................. 41
------------------------------------------------------------------------
Pumpkins............................................. 44
------------------------------------------------------------------------
Quinces.............................................. 53
------------------------------------------------------------------------
Sorghum (including milo)............................. 9
------------------------------------------------------------------------
Squash............................................... 44
------------------------------------------------------------------------
Sunflowers........................................... 25
------------------------------------------------------------------------
Sweet corn........................................... 6
------------------------------------------------------------------------
Tuberous and Corm Vegetables - Crop subgroup 1C 33
(except potatoes)...................................
------------------------------------------------------------------------
Watermelons.......................................... 13
------------------------------------------------------------------------
Wheat................................................ 2
------------------------------------------------------------------------

For the new uses, the Agency used PCT estimates for the chronic
exposure assessment based on usage data and market share projections as
follows. Market share projections for the new uses for thiamethoxam
were obtained from the registrant and compared to 1999-2003 USDA NASS
Usage Data and EPA 2001-2003 Proprietary Usage Data for the
historically, most widely used insecticide for control of insect pests
for each crop. As a result of this comparison, the highest, most
conservative PCT estimate for each crop was used for the chronic
exposure assessment. These highly conservative estimates should not
underestimate actual usage of thiamethoxam on the new crops/sites. To
further support the reliability of these PCT estimates, as a condition
of registration, the registrant will be required to agree to report
annually on the market share attained for the new uses for which
thiamethoxam is registered. As a condition of registration, they will
also be required to agree to mitigate dietary risk as deemed
appropriate by the Agency should the market share data raise a concern
for increased dietary risk. The Agency will then compare that market
share information with the PCT estimates used to evaluate potential
dietary risk. In those instances where percent market share is
approaching or exceeding the predicted PCT estimate used in the
Agency's risk assessment, EPA will conduct a new dietary risk
assessment to evaluate the new dietary risk. If the market share data
raise a concern for increased pesticide risk, the Agency will act to
mitigate that dietary risk and could employ several approaches,
including but not limited to production caps, geographical limitations,
removal of uses, or other means deemed appropriate by the Agency. The
chronic PCT estimates that were used for existing uses are shown in
Table 4:

[[Page 714]]

Table 4.--Thiamethoxam Estimates of Crop Treated for New Uses
------------------------------------------------------------------------
Percent Crop
Commodity Treated
------------------------------------------------------------------------
Beans, lima.......................................... 38
------------------------------------------------------------------------
Beans, snap.......................................... 37
------------------------------------------------------------------------
Bushberries.......................................... 55
------------------------------------------------------------------------
Carrots.............................................. 20
------------------------------------------------------------------------
Cranberries.......................................... 29
------------------------------------------------------------------------
Mint................................................. 9
------------------------------------------------------------------------
Peas, green processed................................ 36
------------------------------------------------------------------------
Peas (including dried peas).......................... 44
------------------------------------------------------------------------
Soybeans............................................. 11
------------------------------------------------------------------------
Strawberries......................................... 46
------------------------------------------------------------------------

The Agency believes that the three conditions listed in this Unit
III. have been met. With respect to Condition 1, PCT estimates are
derived from Federal and private market survey data, which are reliable
and have a valid basis. EPA uses a weighted average PCT for chronic
dietary exposure estimates. This weighted average PCT figure is derived
by averaging State-level data for a period of up to 10 years, and
weighting for the more robust and recent data. A weighted average of
the PCT reasonably represents a person's dietary exposure over a
lifetime, and is unlikely to underestimate exposure to an individual
because of the fact that pesticide use patterns (both regionally and
nationally) tend to change continuously over time, such that an
individual is unlikely to be exposed to more than the average PCT over
a lifetime. As to Conditions 2 and 3, regional consumption information
and consumption information for significant subpopulations is taken
into account through EPA's computer-based model for evaluating the
exposure of significant subpopulations including several regional
groups. Use of this consumption information in EPA's risk assessment
process ensures that EPA's exposure estimate does not understate
exposure for any significant subpopulation group and allows the Agency
to be reasonably certain that no regional population is exposed to
residue levels higher than those estimated by the Agency. Other than
the data available through national food consumption surveys, EPA does
not have available information on the regional consumption of food to
which thiamethoxam may be applied in a particular area.
2. Dietary exposure from drinking water. The Agency lacks
sufficient monitoring exposure data to complete a comprehensive dietary
exposure analysis and risk assessment for thiamethoxam 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 thiamethoxam.
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
reservoir. The screening concentration in ground water (SCIGROW) 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 LOC.
Since the models used are considered to be screening tools in the
risk assessment process, the Agency does not use estimated
environmental concentrations (EECs), which are the model estimates of a
pesticide's concentration in water. EECs derived from these models are
used to quantify drinking water exposure and risk as a %RfD or %PAD.
Instead drinking water levels of comparison (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 thiamethoxam they are
further discussed in the aggregate risk sections in Unit E.
Based on the PRZM/EXAMS and SCIGROW models, the EECs of
thiamethoxam for acute exposures are estimated to be 11.4 parts per
billion (ppb) for surface water and 5 ppb for ground water. The EECs
for chronic non-cancer exposures are estimated to be 0.77 ppb for
surface water and 1.94 ppb for ground water. The EECs for cancer
exposures are estimated to be 0.31 ppb for surface water and 1.94 ppb
for ground water.
Clothianidin is not a significant degradate of thiamethoxam in
water. Therefore, residues of clothianidin in water were estimated
based on applications of clothianidin as an active ingredient. Based on
the FIRST and SCIGROW models, the EECs of clothianidin for acute
exposures are estimated to be 7.29 parts per billion (ppb) for surface
water and 5.84 ppb for ground water. The EECs for chronic exposures are
estimated to be 1.35 ppb for surface water and 5.84 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). Thiamethoxam is not
registered for use on any sites that would result in residential exposure.
Clothianidin is currently registered for use on turfgrasses.
Exposures and risk resulting from clothianidin residues on turfgrasses
are included in the aggregate risk assessment for clothianidin.
4. 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 thiamethoxam and any other
substances and thiamethoxam 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 thiamethoxam has
a common mechanism of toxicity with other substances. For information
regarding EPA's efforts to determine

[[Page 715]]

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/.

D. Safety Factor for Infants and Children

1. In general. Section 408 of FFDCA 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 based on reliable data 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
MOE analysis or through using uncertainty (safety) factors in
calculating a dose level that poses no appreciable risk to humans. In
applying this provision, EPA either retains the default value of 10X
when reliable data do not support the choice of a different factor, or,
if reliable data are available, EPA uses a different additional safety
factor value based on the use of traditional uncertainty factors and/or
special FQPA safety factors, as appropriate.
2. Prenatal and postnatal sensitivity. The developmental toxicity
studies indicated no quantitative or qualitative evidence of increased
susceptibility of rat or rabbit fetus to in utero exposure based on the
fact that the developmental NOAELs are either higher than or equal to
the maternal NOAELs. However, the reproductive studies indicate effects
in males rats in the form of increased incidence and severity of
testicular tubular atrophy. These data are considered to be evidence of
increased quantitative susceptibility for male pups when compared to
the parents.
3. Conclusion. There is a complete toxicity data base for
thiamethoxam and exposure data are complete or are estimated based on
data that reasonably accounts for potential exposures. EPA determined
that the 10X special safety factor to protect infants and children
should be retained, based on the following factors: Effects on
endocrine organs observed across species; the significant decrease in
alanine amino transferase levels in the companion animal studies and in
the dog studies; the mode of action of this chemical in insects
(interferes with the nicotinic acetyl choline receptors of the insect's
nervous system); the transient clinical signs of neurotoxicity in
several studies across species; and the suggestive evidence of
increased quantitative susceptibility in the rat reproduction study.

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 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 water
consumption, and body weights. Default body weights and consumption
values as used by the EPA's Office of Water are used to calculate
DWLOCs: 2 liter (L)/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-level and 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
calculated DWLOCs, 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 a pesticide'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. Using the exposure assumptions discussed in this
unit for acute exposure, the acute dietary exposure from food to
thiamethoxam will occupy 4% of the aPAD for the U.S. population, 2% of
the aPAD for females 13 years and older, 10% of the aPAD for infants
less than one year old, and 11% of the aPAD for children 1 to 2 years
old. In addition, there is potential for acute dietary exposure to
thiamethoxam 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 aPAD, as shown in Table 5 of
this unit:

Table 5.--Aggregate Risk Assessment for Acute Exposure to Thiamethoxam
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup aPAD (mg/ % aPAD Water EEC Water EEC Acute DWLOC
kg) (Food) (ppb) (ppb) (ppb)
----------------------------------------------------------------------------------------------------------------
General U.S. Population........................ 0.1 4 11.4 5 3,400
--------------------------------------------------------------
All infants (less than one year old)........... 0.1 10 11.4 5 900
---------------------------------------------------------------------------
Children 1-2 years old......................... 0.1 11 11.4 5 890
---------------------------------------------------------------------------
Females 13-49 years old........................ 0.1 2 11.4 5 2,900
----------------------------------------------------------------------------------------------------------------

[[Page 716]]

Sources of clothianidin residues in food include uses of both
thiamethoxam and clothianidin. Toxicological doses and endpoints for
clothianidin were used to calculate risk. The acute dietary exposure
from food to the metabolite clothianidin will occupy 18% of the aPAD
for the U.S. population, 12% of the aPAD for females 13 years and
older, 80% of the aPAD for infants less than one year old, and 60% of
the aPAD for children 1 to 2 years old. In addition, there is potential
for acute dietary exposure to clothianidin in drinking water. 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, as shown in Table 6 of this unit:

Table 6.--Aggregate Risk Assessment for Acute Exposure to Clothianidin
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup aPAD (mg/ % aPAD Water EEC Water EEC Acute DWLOC
kg) (Food) (ppb) (ppb) (ppb)
----------------------------------------------------------------------------------------------------------------
General U.S. Population........................ 0.025 18 7.29 5.84 710
--------------------------------------------------------------
All infants (less than one year old)........... 0.025 80 7.29 5.84 48
--------------------------------------------------------------
Children 1-2 years old......................... 0.025 60 7.29 5.84 92
--------------------------------------------------------------
Females 13-49 years old........................ 0.025 12 7.29 5.84 640
----------------------------------------------------------------------------------------------------------------

2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that exposure to
thiamethoxam from food will utilize 6% of the cPAD for the U.S.
population, 11% of the cPAD for infants less than one year old, and 17%
of the cPAD for children 1 to 2 years old. There are no residential
uses for thiamethoxam that result in chronic residential exposure to
thiamethoxam. In addition, there is potential for chronic dietary
exposure to thiamethoxam 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 Table 7 of this unit:

Table 7.--Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Thiamethoxam
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup cPAD (mg/ % cPAD Water EEC Water EEC Chronic
kg) (Food) (ppb) (ppb) DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. population................................ 0.0006 6 0.77 1.94 20
--------------------------------------------------------------
All infants (less than one year old)........... 0.0006 11 0.77 1.94 5.4
--------------------------------------------------------------
Children 1-2 years old......................... 0.0006 17 0.77 1.94 5
--------------------------------------------------------------
Females 13-49 years old........................ 0.0006 5 0.77 1.94 17
----------------------------------------------------------------------------------------------------------------

Sources of clothianidin residues in food include uses of both
thiamethoxam and clothianidin. Toxicological doses and endpoints for
clothianidin were used to calculate risk. Exposure to the metabolite
clothianidin from food will utilize 6% of the cPAD for the U.S.
population, 13% of the cPAD for infants less than one year old, and 15%
of the cPAD for children 1 - 2 years old. Combined residential exposure
estimates range from an MOE of 1,300 for combined oral and dermal
exposure to toddlers (treated turf + treated soil + dermal) to 8,900
for dermal exposure to adults (application + post-application) adults.
In addition, there is potential for chronic dietary exposure to the
metabolite clothianidin 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
Table 8 of this unit:

Table 8.--Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Clothianidin
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup cPAD (mg/ % cPAD Water EEC Water EEC Chronic
kg) (Food) (ppb) (ppb) DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. population................................ 0.0098 6 1.35 5.84 320
--------------------------------------------------------------
All infants (less than one year old)........... 0.0098 13 1.35 5.84 85
--------------------------------------------------------------
Children 1-2 years old......................... 0.0098 15 1.35 5.84 83
--------------------------------------------------------------
Females 13-49 years old........................ 0.0098 5 1.35 5.84 280
--------------------------------------------------------------
Adults 50+ years old........................... 0.0098 5 1.35 5.84 330
----------------------------------------------------------------------------------------------------------------

[[Page 717]]

3. Short-term risk. Short-term aggregate exposure takes into
account residential exposure plus chronic exposure to food and water
(considered to be a background exposure level). Thiamethoxam 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 LOC.
Short-term aggregate exposures from the metabolite clothianidin
result in aggregate MOEs of 5,900 for the general U.S. population,
1,100 for children 1 to 2 years old, and 6,200 for females 13 to 49
years old. These aggregate MOEs do not exceed the Agency's LOC for
aggregate exposure to food and residential uses. In addition, short-
term DWLOCs were calculated and compared to the EECs for chronic
exposure of clothianidin in ground and surface water. After calculating
DWLOCs and comparing them to the EECs for surface water and ground
water, EPA does not expect short-term aggregate exposure to exceed the
Agency's LOC, as shown in Table 9 of this unit:

Table 9.--Aggregate Risk Assessment for Short-Term Exposure to Clothianidin
----------------------------------------------------------------------------------------------------------------
Aggregate Surface Ground
Population Subgroup MOE (Food + Aggregate Water EEC Water EEC Short-Term
Residential) LOC (ppb) (ppb) DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
General U.S. population....................... 5,900 1,000 1.35 5.84 280
--------------------------------------------------------------
Children 1-2 years old........................ 1,100 1,000 1.35 5.84 8.7
--------------------------------------------------------------
Females 13-49 years old....................... 6,200 1,000 1.35 5.84 250
----------------------------------------------------------------------------------------------------------------

4. Intermediate-term risk. Intermediate-term aggregate exposure
takes into account residential exposure plus chronic exposure to food
and water (considered to be a background exposure level). Thiamethoxam
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 LOC.
Intermediate-term aggregate exposures from the metabolite
clothianidin result in aggregate MOEs of 5,900 for the general U.S.
population, 1,100 for children 1 to 2 years old, and 6,200 for females
13 to 49 years old. These aggregate MOEs do not exceed the Agency's LOC
for aggregate exposure to food and residential uses. In addition,
intermediate-term DWLOCs were calculated and compared to the EECs for
chronic exposure of clothianidin in ground water and surface water.
After calculating DWLOCs and comparing them to the EECs for surface
water and ground water, EPA does not expect intermediate-term aggregate
exposure to exceed the Agency's LOC, as shown in Table 10 of this unit:

Table 10.--Aggregate Risk Assessment for Intermediate-Term Exposure to Clothianidin
----------------------------------------------------------------------------------------------------------------
Aggregate Surface Ground Intermediate-
Population Subgroup MOE (Food + Aggregate Water EEC Water EEC Term DWLOC
Residential) LOC (ppb) (ppb) (ppb)
----------------------------------------------------------------------------------------------------------------
General U.S. population..................... 5,900 1,000 1.35 5.84 280
------------------------------------------------------------
Children 1-2 years old...................... 1,100 1,000 1.35 5.84 8.7
------------------------------------------------------------
Females 13-49 years old..................... 6,200 1,000 1.35 5.84 250
----------------------------------------------------------------------------------------------------------------

5. Aggregate cancer risk for U.S. population. In conducting the
aggregate cancer risk assessment, only dietary and drinking water
pathways of exposure were considered. At this time, there are no uses
for thiamethoxam that would result in any non-occupational, non-dietary
exposure (i.e., there are no dermal or inhalation routes of exposure
that should be included in an aggregate assessment). A DWLOC was
derived for the general U.S. population based on EPA's LOC for cancer
or a risk in the range of 1 in 1 million. The DWLOC is compared to the
estimated environmental concentrations of thiamethoxam in surface and
ground water and is used to determine whether or not aggregate cancer
exposures are likely to result in risk estimates that exceed EPA's LOC.
Table 11 of this unit summarizes the drinking water estimated
concentrations of thiamethoxam in surface water and ground water and
the associated DWLOC for cancer:

Table 11.--Aggregate Risk Assessment for Cancer Exposure to Thiamethoxam
----------------------------------------------------------------------------------------------------------------
Maximum
Maximum Food Water Cancer Ground Surface
Population Subgroup Exposure mg/ Exposure mg/ Exposure mg/ DWLOC ppb Water EEC Water EEC
kg/day kg/day kg/day ppb ppb
----------------------------------------------------------------------------------------------------------------
General U.S. population........... 7.96 x 10\- 7.96 x 10\- 7.96 x 10\- 1.87 1.94 0.31
\5 \5 \5
----------------------------------------------------------------------------------------------------------------

[[Page 718]]

For cancer, the DWLOC is slightly less than the ground water EEC.
However, the cancer DWLOC is based on a conservative estimate of
dietary exposure. Available information from actual prospective ground
water monitoring data demonstrates that actual thiamethoxam residues in
groundwater occur at or below 0.05 ppb. This interim analysis suggests
that actual long-term residues of thiamethoxam in ground water will be
significantly less than the levels predicted by the SCIGROW model. A
significant decrease in the level of thiamethoxam in drinking water
results in an aggregate risk estimate that is unlikely to exceed EPA's
LOC for cancer. Further, the DWLOC numerical computation was done using
a cancer risk figure of 1 in 1 million although EPA has repeatedly
found that risk figures marginally higher than 1 in 1 million fall
within the range of a 1 in 1 million risk.
6. 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 thiamethoxam residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

Adequate enforcement methodology (aqueous acetonitrile solvent
extraction, liquid-liquid partitioning and solid-phase extraction
cleanup, and high pressure liquid chromatography/ultraviolet (HPLC/UV)
analysis) is available to enforce the tolerance expression. The method
may be requested from: Chief, Analytical Chemistry Branch,
Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD 20755-5350;
telephone number: (410) 305-2905; e-mail address:
residuemethods@epa.gov.

B. International Residue Limits

There are no international residue limits for thiamethoxam.

V. Conclusion

Therefore, the tolerance is established for combined residues of
thiamethoxam, 3-[(2-chloro-5-thiazolyl)methyl]tetrahydro-5-methyl-N-
nitro-4H-1,3,5-oxadiazin-4-imine and its metabolite (N-(2-chloro-
thiazol-5-ylmethyl)-N`-methyl-N'`-nitro-guanidine), in or on legume
vegetables group 6 at 0.02 ppm, peppermint and spearmint at 1.5 ppm;
root vegetables (except sugar beet) crop subgroup 1B at 0.02 ppm and
for radish tops at 0.80 ppm; strawberry at 0.30 ppm; cranberry at 0.02
ppm; bushberry crop subgroup 13B and juneberry, lingonberry and salal
at 0.20 ppm; rapeseed seed, mustard seed, flax seed, safflower seed,
crambe seed, and borage seed at 0.02 ppm; and potato at 0.25 ppm. In
addition, the tolerance expression for tuberous and corm crop subgroup
1C is revised to a tolerance expression for tuberous and corm (except
potato) crop subgroup 1D.

VI. Objections and Hearing Requests

Under section 408(g) of FFDCA, as amended by 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 FFDCA by FQPA, EPA
will continue to use those procedures, with appropriate adjustments,
until the necessary modifications can be made. The new section 408(g)
of FFDCA 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) of FFDCA, as was
provided in the old sections 408 and 409 of FFDCA. 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-2004-0394 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 March 7,
2005.
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 (1900L),
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460-0001. You may also deliver your request to the
Office of the Hearing Clerk in Suite 350, 1099 14th St., NW.,
Washington, DC 20005. 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) 564-6255.
2. 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 ADDRESSES. Mail your
copies, identified by docket ID number OPP-2004-0394, 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-
0001. In person or by courier, bring a copy to the location of the
PIRIB described in ADDRESSES. 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 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).

[[Page 719]]

VII. Statutory and Executive Order Reviews

This final rule establishes a tolerance under section 408(d) of
FFDCA 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 section 408(d) of FFDCA, 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, entitled Federalism
(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 section 408(n)(4) of FFDCA. 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 (59 FR 22951, 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. Congressional Review Act

The Congressional Review Act, 5 U.S.C. 801 et seq., as added by 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 the U.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: December 22, 2004.
Lois Rossi,
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), 346a and 371.

? 2. Section 180.565 is amended by alphabetically adding commodities to
the table in paragraph (a) to read as follows:

Sec. 180.565 Thiamethoxam; tolerances for residues.

(a) * * *

------------------------------------------------------------------------
Commodity Parts per million
------------------------------------------------------------------------
* * * * *
Borage, seed......................................... 0.02
* * * * *
Bushberry, subgroup 13B.............................. 0.20
* * * * *
Crambe, seed......................................... 0.02
Cranberry............................................ 0.02
Flax, seed........................................... 0.02
* * * * *
Juneberry............................................ 0.20
Lingonberry.......................................... 0.20
* * * * *
Mustard, seed........................................ 0.02
Peppermint........................................... 1.5
Potato............................................... 0.25
Radish, tops......................................... 0.80
Rapeseed, seed....................................... 0.02
Safflower, seed...................................... 0.02
Salal................................................ 0.20
* * * * *
Spearmint............................................ 1.5
Strawberry........................................... 0.3
* * * * *
Vegetable, legume, group 6........................... 0.02
Vegetable, root, except sugar beet, subgroup 1B...... 0.02
------------------------------------------------------------------------

* * * * *
? 3. Section 180.565 is amended by revising the tolerance expression for
Tuberous and Corm Vegetables Crop Subgroup in the table in paragraph
(a) to

[[Page 720]]

read Vegetable, tuberous and corm, except potato, subgroup 1D.
* * * * *

[FR Doc. 05-89 Filed 1-4-05; 8:45 am]
BILLING CODE 6560-50-S

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