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Thiamethoxam - Pesticide Tolerances for Emergency Exemptions 12/00

ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-301080; FRL-6755-8]
RIN 2070-AB78
Thiamethoxam; Pesticide Tolerances for Emergency Exemptions
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.

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SUMMARY: This regulation establishes time-limited tolerances for
combined residues of thiamethoxam and its CGA-322704 metabolite in or
on cotton, milk, and meat and meat byproducts of cattle, goats, horses
and sheep. This action is in response to EPA's granting of an emergency
exemption under section 18 of the Federal Insecticide, Fungicide, and
Rodenticide Act authorizing use of the pesticide on cotton. This
regulation establishes maximum permissible levels for residues of
thiamethoxam in this food commodity. These tolerances will expire and
are revoked on December 31, 2002.

DATES: This regulation is effective December 20, 2000.Objections and
requests for hearings, identified by docket control number OPP-301080,
must be received by EPA on or before February 20, 2001.

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 VII. of the SUPPLEMENTARY
INFORMATION. To ensure proper receipt by EPA, your objections and
hearing requests must identify docket control number OPP-301080 in the
subject line on the first page of your response.

FOR FURTHER INFORMATION CONTACT: By mail: Stephen Schaible,
Registration Division (7505C), Office of Pesticide Programs,
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460; telephone number:703-308-9362; and e-mail
address: schaible.stephen@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 categories and entities may include, but are not
limited to:

------------------------------------------------------------------------
                                                 Examples of Potentially
             Categories                 NAICS       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 this
document, 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/. 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 control number OPP-301080. 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, 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

    EPA, on its own initiative, in accordance with sections 408(e) and
408 (l)(6) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21
U.S.C. 346a, is 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 CGA-322704
metabolite in or on cotton, undelinted seed at 0.1 part per million
(ppm); cotton, gin byproducts at 1.5 ppm; milk at 0.02 ppm; meat of
cattle, goats, horses and sheep at 0.02 ppm; and meat byproducts of
cattle, goats, horses and sheep at 0.02 ppm. These tolerances will
expire and are revoked on December 31, 2002. EPA will publish a
document in the Federal Register to remove the revoked tolerances from
the Code of Federal Regulations.
    Section 408(l)(6) of the FFDCA requires EPA to establish a time-
limited tolerance or exemption from the requirement for a tolerance for
pesticide chemical residues in food that will result from the use of a
pesticide under an emergency exemption granted by EPA under section 18
of FIFRA. Such tolerances can be established without providing notice
or period for public comment. EPA does not intend for its actions on
section 18 related tolerances to set binding precedents for the
application of section 408 and the new safety standard to other
tolerances and exemptions. Section 408(e) of the FFDCA allows EPA to
establish a tolerance or an exemption from the requirement of a
tolerance on its own initiative, i.e., without having received any
petition from an outside party.
    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

[[Page 79756]]

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. . . ."
    Section 18 of the Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA) authorizes EPA to exempt any Federal or State agency from
any provision of FIFRA, if EPA determines that "emergency conditions
exist which require such exemption." This provision was not amended by
the Food Quality Protection Act (FQPA). EPA has established regulations
governing such emergency exemptions in 40 CFR part 166.

III. Emergency Exemption for Thiamethoxam on Cotton and FFDCA
Tolerances

    According to the Applicant, cotton aphid infestations have begun to
develop earlier in the production season and consistent control of this
pest has become difficult to achieve with currently available
materials. It is claimed that cotton aphid has developed resistance to
most currently labeled and recommended insecticides in Mississippi, and
laboratory assays, field experiments and field experience indicate that
insecticides currently recommended for aphid control are variable in
effectiveness. EPA has authorized under FIFRA section 18 the use of
thiamethoxam on cotton for control of cotton aphids in Mississippi.
After having reviewed this submission, EPA concurs that an emergency
condition exists for this State.
    As part of its assessment of this emergency exemption, EPA assessed
the potential risks presented by residues of thiamethoxam and its
metabolite in or on cotton, as well as the potential risk presented by
secondary residues of thiamethoxam and its metabolite in milk, meat,
and meat byproducts of cattle, goats, horses and sheep. In doing so,
EPA considered the safety standard in FFDCA section 408(b)(2), and EPA
decided that the necessary tolerances under FFDCA section 408(l)(6)
would be consistent with the safety standard and with FIFRA section 18.
Consistent with the need to move quickly on the emergency exemption in
order to address urgent non-routine situations and to ensure that the
resulting food is safe and lawful, EPA is issuing these tolerances
without notice and opportunity for public comment as provided in
section 408(l)(6). Although these tolerances will expire and are
revoked on December 31, 2002, under FFDCA section 408(l)(5), residues
of the pesticide not in excess of the amounts specified in the
tolerances remaining in or on cotton, undelinted seed; cotton, gin
byproducts; milk; meat of cattle, goats, horses and sheep; and meat
byproducts of cattle, goat, horses and sheep after that date will not
be unlawful, provided the pesticide is applied in a manner that was
lawful under FIFRA, and the residues do not exceed levels that were
authorized by these tolerances at the time of that application. EPA
will take action to revoke these tolerances earlier if any experience
with, scientific data on, or other relevant information on this
pesticide indicate that the residues are not safe.
    Because these tolerances are being approved under emergency
conditions, EPA has not made any decisions about whether thiamethoxam
meets EPA's registration requirements for use on cotton or whether
permanent tolerances for this use would be appropriate. Under these
circumstances, EPA does not believe that these tolerances serve as a
basis for registration of thiamethoxam by a State for special local
needs under FIFRA section 24(c). Nor do these tolerances serve as the
basis for any State other than Mississippi to use this pesticide under
section 18 of FIFRA without following all provisions of EPA's
regulations implementing section 18 as identified in 40 CFR part 166.
For additional information regarding the emergency exemption for
thiamethoxam, contact the Agency's Registration Division at the address
provided under FOR FURTHER INFORMATION CONTACT.

IV. Aggregate Risk Assessment and Determination of Safety

    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).
    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
thiamethoxam and to make a determination on aggregate exposure,
consistent with section 408(b)(2), for time-limited tolerances for
combined residues of thiamethoxam and its metabolite in or on cotton,
undelinted seed at 0.1 ppm; cotton, gin byproducts at 1.5 ppm; milk at
0.02 ppm; meat of cattle, goats, horses and sheep at 0.02 ppm; and meat
byproducts of cattle, goats, horses and sheep at 0.02 ppm. EPA's
assessment of the dietary exposures and risks associated with
establishing these tolerances follows.

A. 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 endpoint. However, the
lowest dose at which adverse effects of concern are identified (the
LOAEL) is sometimes used for risk assessent 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 level of concern (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 as 1  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

[[Page 79757]]

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
(MOEcancer = point of departure/exposures) is calculated. A
summary of the toxicological endpoints for thiamethoxam used for human
risk assessment is shown in the following Table 1:

Table 1.--Summary of Toxicological Dose and Endpoints for Thiamethoxam
 for Use in Human Risk Assessment
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                                        FQPA SF\*\ and Level of
Exposure Scenario    Dose Used in Risk Concern for Risk     Study and Toxicological
                              Assessment, UF Assessment                Effects
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Acute Dietary general population   NOAEL = 100 mg/kg/day;   FQPA SF = 10; aPAD =
 including infants and children     UF = 100; Acute RfD = acute RfD/FQPA SF =
                                      1 mg/kg/day              0.1 mg/kg/day
Acute mammalian
neurotoxicity study in the rat
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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Chronic Dietary all populations  NOAEL= 0.6 mg/kg/day;    FQPA SF = 10; cPAD =
                                        UF = 100; Chronic RfD chronic RfD/FQPA SF =
                                        = 0.006 mg/kg/day 0.0006 mg/kg/day
2-Generation
reproduction study
LOAEL = 1.8 mg/kg/day
based on increased
incidence and severity
of tubular atrophy in
testes of F1
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)-1 is 3.77  x  10-2 in human equivalents.
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\*\ The reference to the FQPA Safety Factor refers to any additional safety
 factor retained due to concerns unique to the FQPA.

B. Exposure Assessment

    1. Dietary exposure from food and feed uses. Thiamethoxam is a new
chemical with tolerance petitions pending at the Agency for a variety
of raw agricultural commodities, but no tolerances established at this
time. Risk assessments were conducted by EPA to assess dietary
exposures from residues of thiamethoxam and its metabolite in cotton as
well as secondary residues in milk, meat and meat byproducts resulting
from potential use of treated cotton as a feed item; descriptions of
these risk assessments are 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. The Dietary Exposure Evaluation Model (DEEM)
analysis evaluated 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 following assumptions were made for the acute
exposure assessments: tolerance level residues and 100% of crop treated
were assumed for all commodities evaluated. These assumptions are
highly conservative and result in overestimation of exposure.
    ii. Chronic exposure. In conducting this chronic dietary risk
assessment the Dietary Exposure Evaluation Model (DEEM)
analysis evaluated 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 following assumptions were made for the chronic
exposure assessments: a Tier 3 risk assessment was conducted in which
refined residues and percent of crop treated information were
incorporated.
    iii. Cancer. In conducting this chronic dietary risk assessment for
a cancer endpoint the Dietary Exposure Evaluation Model
(DEEM) analysis evaluated 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 following assumptions were made
for the chronic exposure assessments: a Tier 3 risk assessment was
conducted in which refined residues and percent of crop treated
information were incorporated.
    iv. Anticipated residue and percent crop treated information.
Section 408(b)(2)(E) 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 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. As required by section 408(b)(2)(E), EPA will
issue a data call-in for information relating to anticipated residues
to be submitted no later than 5 years from the date of issuance of this
tolerance.
    Section 408(b)(2)(F) 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

[[Page 79758]]

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), EPA may require registrants to submit data on
PCT.
    The Agency used percent crop treated (PCT) information as follows:
    A Tier 3 chronic dietary exposure analysis for the insecticide
thiamethoxam was based on 21% of the cotton crop being treated. The
estimate of 21% was calculated by comparing the projected base acres of
cotton to be treated annually to the total acres of cotton grown in the
United States according to market survey data. Base acres were
calculated by multiplying the percentage projected replacement of an
alternative by thiamethoxam to control a specific cotton pest by the
acres treated once by this alternative, summing across pests.
    Anticipated residue values (ARs) for cotton commodities which were
used in the chronic and cancer dietary risk assessments were calculated
from field trial data. Refined concentration/dilution factors derived
from a cottonseed processing study were also used. ARs for livestock
commodities used projected market share estimates and average residues
from field trials for feed items, in addition to residue data derived
from feeding and metabolism studies.
    The Agency believes that the three conditions previously discussed
have been met. With respect to Condition 1, EPA finds that the PCT
information described above for thiamethoxam used on cotton is reliable
and has a valid basis. The PCT estimate is derived from market survey
data relating to insecticide use on cotton. As the time-limited
tolerances being established for cotton commodities are in conjunction
with the section 18 use of thiamethoxam on cotton in Mississippi and
not use nationwide, this percent of crop treated value is considered an
overestimate for the purposes of this risk assessment. 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 Generic Estimated Environmental Concentration
(GENEEC) or the Pesticide Root Zone/Exposure Analysis Modeling System
(PRZM/EXAMS) to estimate pesticide concentrations in surface water and
SCI-GROW, which predicts pesticide concentrations in groundwater. In
general, EPA will use GENEEC (a tier 1 model) before using PRZM/EXAMS
(a tier 2 model) for a screening-level assessment for surface water.
The GENEEC model is a subset of the PRZM/EXAMS model that uses a
specific high-end runoff scenario for pesticides. GENEEC incorporates a
farm pond scenario, while PRZM/EXAMS incorporate an index reservoir
environment in place of the previous pond scenario. 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 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 below.
    Based on the PRZM/EXAMS and SCI-GROW models the estimated
environmental concentrations (EECs) of thiamethoxam for acute exposures
are estimated to be 8.0 parts per billion (ppb) for surface water and
1.55 ppb for ground water. The EECs for chronic exposures are estimated
to be 0.6 ppb for surface water and 1.55 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.
    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 thiamethoxam 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,
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 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).

[[Page 79759]]

C. Safety Factor for Infants and Children

    1. Safety factor for infants and children--i. 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.
    ii. Developmental toxicity studies. There is no quantitative or
qualitative evidence of increased susceptibility of rats or rabbit
fetuses to in utero exposure to thiamethoxam in the rat or rabbit
developmental toxicity studies. The developmental NOAELs are either
higher than or equal to the maternal NOAELs. The toxicological effects
in fetuses do not appear to be any more severe than those in the dams
or does.
    iii. Reproductive toxicity study. In the two-generation
reproduction study, there is evidence of increased quantitative
susceptibility for male pups. Reproductive effects in males appear in
the F1 generation in the form of increased incidence and
severity of testicular tubular atrophy at the LOAEL of 1.8 mg/kg/day
(NOAEL: 0.6 mg/kg/day). The increase in severity is based on an
increased incidence of grade 2 minute focal tubular changes. These
animals were exposed to the test material in utero whereas the
F0 males, which did not have these effects, were not exposed
to the test material in utero. For parents, the NOAEL is 1.8 mg/kg/day
for hyaline changes in renal tubules at the LOAEL of 61 mg/kg/day.
    iv. Prenatal and postnatal sensitivity. Since no data are available
to indicate how the testicular effects occur, whether or not they can
be considered an endocrine effect (effects are observed in other
endocrine organs in three species), or whether or not they can
definitively be considered adverse, the Agency has determined that
there is evidence of increased quantitative susceptibility for male
pups when compared to the parents.
    v. Conclusion. The toxicity data base for thiamethoxam is
incomplete. Based on 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, transient
clinical signs of neurotoxicity in several studies, and the fact that
the mode of action of this insecticide on insects is through a
neurologic mechanism, a developmental neurotoxicity study is being
required. Exposure data are complete or are estimated based on data
that reasonably accounts for potential exposures. The FQPA safety
factor was retained at 10x in assessing the acute and chronic risk
posed by this chemical for all populations based on increased
susceptibility of male pups in the reproduction study, lack of key
measurements in the reproduction study and the need for a developmental
neurotoxicity study.

D. 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 + chronic non-dietary, non-occupational 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 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-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 groundwater are less than the
calculated DWLOCs, OPP concludes with reasonable certainty that
exposures to thiamethoxam in drinking water (when considered along with
other sources of exposure for which OPP has reliable data) would not
result in unacceptable levels of aggregate human health risk at this
time. Because OPP 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, OPP will reassess the potential impacts of
thiamethoxam on drinking water as a part of the aggregate risk
assessment process.
    1. Acute risk. Using the Tier 1 exposure assumptions discussed in
this unit for acute exposure, the acute dietary exposure from food to
thiamethoxam and its metabolite will occupy less than 1% of the aPAD
for the U.S. population, 2% of the aPAD for non-nursing infants less
than 1 year old and 1% of the aPAD for children 1-6 years old at the
95th percentile of exposure. In addition, despite the potential for
acute dietary exposure to thiamethoxam in drinking water, after
calculating DWLOCs and comparing them to conservative model estimated
environmental concentrations of thiamethoxam in surface and ground
water, EPA does not expect the aggregate exposure to exceed 100% of the
aPAD, as shown in the following Table 2:

Table 2.--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)
---------------------------------------------------------------------------------------------------
U.S. population                             0.1 <1          8.0         1.55        3,479
---------------------------------------------------------------------------------------------------
All infants  <1 yr.                          0.1 2          8.0         1.55          986
---------------------------------------------------------------------------------------------------
Children 1-6 yrs.                           0.1 1          8.0         1.55          987
---------------------------------------------------------------------------------------------------

[[Page 79760]]

    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 less than 1% of the cPAD for the
U.S. population and all sensitive subpopulations of concern, including
infants and children. There are no residential uses for thiamethoxam
that result in chronic residential exposure to thiamethoxam. In
addition, despite the potential for chronic dietary exposure to
thiamethoxam in drinking water, after calculating DWLOCs and comparing
them to conservative model estimated environmental concentrations of
thiamethoxam in 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 Thiamethoxam
---------------------------------------------------------------------------------------------------
                                                  Surface       Ground
Population Subgroup      cPAD mg/kg/     % cPAD     Water EEC    Water EEC     Chronic
                                      day (Food)       (ppb)        (ppb)     DWLOC (ppb)
---------------------------------------------------------------------------------------------------
U.S. Population                          0.0006 <1         0.06         1.55           21
---------------------------------------------------------------------------------------------------
All infants < 1 yr.                      0.0006 <1         0.06         1.55            6
---------------------------------------------------------------------------------------------------
Children 1-6 yrs.                        0.0006 <1         0.06         1.55            6
---------------------------------------------------------------------------------------------------

    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 risks from food and water, which were previously addressed.
    4. Intermediate-term risk. Intermediate-term aggregate exposure
takes into account non-dietary, non-occupational 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 risks from food and water, which were previously addressed.
    5. Aggregate cancer risk for U.S. population. Using the exposure
assumptions described in this unit for cancer risk assessment and
applying the upper-bound potency factor (Q1*)
value of 0.0377 (mg/kg/day)-1, the dietary (food only)
cancer risk associated with thiamethoxam use on cotton and secondary
residues in milk, meat and meat byproducts is 2.9  x  10-8.
This risk estimate is fairly refined, incorporating both anticipated
residues (from field trial data) and percent of market share data into
the analysis. There are no residential uses for thiamethoxam that
result in chronic residential exposure to thiamethoxam and would be
considered in an aggregate cancer risk assessment. In addition, despite
the potential for chronic dietary exposure to thiamethoxam in drinking
water, after calculating a DWLOC and comparing it to conservative
models estimated environmental concentrations of thiamethoxam in
surface and ground water, EPA does not expect the aggregate exposure to
exceed the negligible risk. The calculated DWLOC for chronic, cancer
effects of 2.75 ppb is not exceeded by estimated environmental
concentrations of thiamethoxam in surface water and groundwater of 0.06
ppb and 1.55 ppb, respectively. Therefore, EPA concludes with
reasonable certainty that exposures to thiamethoxam in drinking water
(when considered along with other sources of exposure for which OPP has
reliable data) would not result in unacceptable levels of aggregate
human health risk at this time.
    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.

V. Other Considerations

A. Analytical Enforcement Methodology

    An adequate enforcement methodology for both plants and animals is
available to enforce the tolerance expression. Method AG-675 (HPLC/UV)
for residues of thiamethoxam and CGA-322704 has undergone a successful
independent laboratory validation (ILV) trial. The method may be
requested from: Calvin Furlow, PIRIB, IRSD (7502C), Office of Pesticide
Programs, Environmental Protection Agency, 1200 Pennsylvania Ave., NW,
Washington, DC 20460; telephone number: (703) 305-5229; e-mail address:
furlow.calvin@epa.gov.

B. International Residue Limits

    As there are no Codex, Canadian, or Mexican MRLs/tolerances
established for residues of thiamethoxam in plant or animal
commodities, a discussion of compatibility with U.S. tolerances is not
relevant at this time.

C. Conditions

    No conditions are required in conjunction with the establishment of
these time-limited tolerances.

VI. Conclusion

    Therefore, the tolerances are 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 CGA-322704, in or
on cotton, undelinted seed at 0.1 ppm; cotton, gin byproducts at 1.5
ppm; milk at 0.02 ppm; meat of cattle, goats, horses and sheep at 0.02
ppm; and meat byproducts of cattle, goats, horses and sheep at 0.02
ppm.

VII. 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.

[[Page 79761]]

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 control number OPP-301080 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 February
20, 2001.
    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 VII.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 the docket control number OPP-301080, 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 file format 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).

VIII. Regulatory Assessment Requirements

    This final rule establishes time-limited tolerances under FFDCA
section 408. 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).
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 prior consultation
as specified by Executive Order 13084, entitled Consultation and
Coordination with Indian Tribal Governments (63 FR 27655, May 19,
1998); special considerations as required by Executive Order 12898,
entitled Federal Actions to Address Environmental Justice in Minority
Populations and Low- Income Populations (59 FR 7629, February 16,
1994); or require 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 FIFRA
section 18 exemption under FFDCA section 408, such as the tolerances 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

[[Page 79762]]

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).

IX. Submission to Congress and the Comptroller General

    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 6, 2000.

Joseph J. Merenda,

Acting Director, 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 added to read as follows:

Sec. 180.565  Thiamethoxam; tolerances for residues.

    (a) General. [Reserved]
    (b) Section 18 emergency exemptions. Time-limited tolerances are
established 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 CGA-322704 metabolite in connection with use
of the pesticide under section 18 emergency exemptions granted by EPA.
These tolerances will expire and are revoked on the dates specified in
the following table.

------------------------------------------------------------------------
                                           Parts per      Expiration/
                Commodity                   million     revocation date
------------------------------------------------------------------------
Cattle, meat............................         0.02           12/31/02
Cattle, meat byproducts.................         0.02           12/31/02
Cotton, undelinted seed.................          0.1           12/31/02
Cotton, gin byproducts..................          1.5           12/31/02
Goat, meat..............................         0.02           12/31/02
Goat, meat byproducts...................         0.02           12/31/02
Horse, meat.............................         0.02           12/31/02
Horse, meat byproducts..................         0.02           12/31/02
Milk....................................         0.02           12/31/02
Sheep, meat.............................         0.02           12/31/02
Sheep, meat byproducts..................         0.02           12/31/02
------------------------------------------------------------------------

    (c) Tolerances with regional registrations. [Reserved]
    (d) Indirect or inadvertent residues. [Reserved]

[FR Doc. 00-32400 Filed 12-19-00; 8:45 am]
BILLING CODE 6560-50-S