[Federal Register Volume 65, Number 245 (Wednesday, December 20, 2000)]
[Rules and Regulations]
[Pages 79755-79762]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-32400]



[[Page 79755]]

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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: [email protected].

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 =     Acute mammalian
 including infants and children         UF = 100; Acute RfD =    acute RfD/FQPA SF =      neurotoxicity study in
                                        1 mg/kg/day              0.1 mg/kg/day            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 =     2-Generation
                                        UF = 100; Chronic RfD    chronic RfD/FQPA SF =    reproduction study
                                        = 0.006 mg/kg/day        0.0006 mg/kg/day
                                                                                         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.
----------------------------------------------------------------------------------------------------------------
\*\ 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: 
[email protected].

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 [email protected], 
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: [email protected]. 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