[Federal Register Volume 69, Number 180 (Friday, September 17, 2004)]
[Rules and Regulations]
[Pages 55975-55982]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-20983]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-2004-0277; FRL-7679-4]


Thifensulfuron Methyl; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes a tolerance for residues of 
thifensulfuron methyl in or on canola, seed; cotton, gin byproducts; 
cotton, undelinted seed; and flax, seed. E. I. DuPont de Nemours & 
Company requested this tolerance under the Federal Food, Drug, and 
Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of 
1996 (FQPA). In addition, this regulatory action is part of the 
tolerancere assessment requirements of section 408 (q) of the Federal 
Food, Drug, and Cosmetic Act (FFDCA) 21 U. S. C. 346a (q), as amended 
by the Food Quality Protection Act (FQPA) of 1996. By law, EPA is 
required to reassess 100% of the tolerances in existence on August 2, 
1996, by August 2006. This regulatory action will count for 10 
reassessments toward the August 2006 deadline.

DATES: This regulation is effective September 17, 2004. Objections and 
requests for hearings must be received on or before November 16, 2004.

ADDRESSES: To submit a written objection or hearing request follow the 
detailed instructions as provided in Unit VI. of the SUPPLEMENTARY 
INFORMATION. EPA has established a docket for this action under Docket 
identification (ID) number OPP-2004-0277. All documents in the docket 
are listed in the EDOCKET index at http://www.epa.gov/edocket. Although 
listed in the index, some information is not publicly available, i.e., 
CBI or other information whose disclosure is restricted by statute. 
Certain other material, such as copyrighted material, is not placed on 
the Internet and will be publicly available only in hard copy form. 
Publicly available docket materials are available either electronically 
in EDOCKET or in hard copy at the Public Information and Records 
Integrity Branch (PIRIB), Rm. 119, Crystal Mall 2, 1801 S. 
Bell St., Arlington, VA. This docket facility is open from 8:30 a.m. to 
4 p.m., Monday through Friday, excluding legal holidays. The docket 
telephone number is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: James A. Tompkins, Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW.,Washington, DC 20460-
0001; telephone number: (703) 305-5697; 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 entities may include, but are not limited to:
     Crop production (NAICS 111), e.g., agricultural workers; 
greenhouse, nursery, and floriculture workers; farmers.
     Animal production (NAICS 112), e.g., cattle ranchers and 
farmers, dairy cattle farmers, livestock farmers.
     Food manufacturing (NAICS 311), e.g., agricultural 
workers; farmers; greenhouse, nursery, and floriculture workers; 
ranchers; pesticide applicators.
     Pesticide manufacturing (NAICS 32532), e.g., agricultural 
workers; commercial applicators; farmers; greenhouse, nursery, and 
floriculture workers; residential users.
    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in this unit could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether this action might apply to certain entities. If you have any 
questions regarding the applicability of this action to a particular 
entity, consult the person listed under FOR FURTHER INFORMATION 
CONTACT.

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

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

II. Background and Statutory Findings

    In the Federal Register of July 7, 2004 (69 FR 40920) (FRL-7364-7), 
EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C. 
346a(d)(3), announcing the filing of a pesticide petition (PP 0F6152) 
by E.I. DuPont de Nemours and Company, DuPont Agricultural Products, 
Barley Mill Plaza, Wilmington, DE 19880-0038. The petition requested 
that 40 CFR 180.439 be amended by establishing a tolerance for residues 
of the herbicide thifensulfuron methyl, (methyl-3-[[[[(4-methoxy-6-
methyl-1, 3, 5, -triazin-2-yl)amino]carbonyl]amino]sulfonyl]-2-
thiophenecarboxylate), in or on imazethapyr tolerant canola seed at 
0.02 parts per million (ppm), cotton seed at 0.02 ppm, cotton gin trash 
at 0.02 ppm, and CDC triffid flax at 0.02 ppm. That notice included a 
summary of the petition prepared by E. I. DuPont de Nemours & Company, 
the registrant. There were no comments received in response to the 
notice of filing.
    During the course of the review the Agency decided to correct the 
Company address and correct the listings for the commodities canola, 
cotton gin trash, cottonseed, and flax. The company address is changed 
to DuPont Crop Protection, Stine-Haskell Research Center, Newark, DE 
19714. The listing of the commodities imazethapyr tolerant canola, 
cotton seed, cotton gin trash, and Crop Development Center (CDC) 
triffid flax are corrected to read canola, seed; cotton, gin 
byproducts; cotton, undelinted seed; and flax, seed; respectively.
    Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a 
tolerance (the legal limit for a pesticide chemical residue in or on a 
food) only if EPA determines that the tolerance is ``safe.'' Section 
408(b)(2)(A)(ii) of FFDCA defines ``safe'' to mean that`` there is a 
reasonable certainty that no harm will result from aggregate exposure 
to the pesticide chemical residue, including all anticipated dietary 
exposures and all other exposures for which there is reliable 
information.'' This includes exposure through drinking water and in

[[Page 55976]]

residential settings, but does not include occupational exposure. 
Section 408(b)(2)(C) of FFDCA requires EPA to give special 
consideration to exposure of infants and children to the pesticide 
chemical residue in establishing a tolerance and to ``ensure that there 
is a reasonable certainty that no harm will result to infants and 
children from aggregate exposure to the pesticide chemical 
residue....''
    EPA performs a number of analyses to determine the risks from 
aggregate exposure to pesticide residues. For further discussion of the 
regulatory requirements of section 408 of FFDCA and a complete 
description of the risk assessment process, see the final rule on 
Bifenthrin Pesticide Tolerances (62 FR 62961, November 26, 1997) (FRL-
5754-7).

III. Aggregate Risk Assessment and Determination of Safety

    Consistent with section 408(b)(2)(D) of FFDCA, EPA has reviewed the 
available scientific data and other relevant information in support of 
this action. EPA has sufficient data to assess the hazards of and to 
make a determination on aggregate exposure, consistent with section 
408(b)(2) of FFDCA, for a tolerance for residues of thifensulfuron 
methyl on canola, seed at 0.02 ppm; cotton, gin byproducts at 0.02 ppm; 
cotton, undelinted seed at 0.02 ppm; and flax, seed at 0.02 ppm. EPA's 
assessment of exposures and risks associated with establishing the 
tolerance follows.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its 
validity, completeness, and reliability as well as the relationship of 
the results of the studies to human risk. EPA has also considered 
available information concerning the variability of the sensitivities 
of major identifiable subgroups of consumers, including infants and 
children. The nature of the toxic effects caused by thifensulfuron 
methyl are discussed in Table 1 of this unit as well as the no-
observed-adverse-effect-level (NOAEL) and the lowest-observed-adverse-
effect-level (LOAEL) from the toxicity studies reviewed.

                                Table 1.--Subchronic, Chronic, and Other Toxicity
----------------------------------------------------------------------------------------------------------------
             Guideline No.                       Study Type                            Results
----------------------------------------------------------------------------------------------------------------
870.3100                                 90-day oral toxicity--      NOAEL = 7 and 9 milligrams/kilogram/day (mg/
                                          rodents                     kg/day) males and females, respectively
                                                                     LOAEL = 177(males) and 216(females) mg/kg/
                                                                      day based on decreased body weight, body
                                                                      weight gain and organ weight
----------------------------------------
870.3150                                 90-day oral toxicity--      NOAEL = 37.5 mg/kg/day
                                          nonrodents                 LOAEL = 187.5 mg/kg/day based on decreased
                                                                      body weight and actual weight in high dose
                                                                      males
----------------------------------------
870.3700                                 Prenatal developmental--    Maternal NOAEL = 725 mg/kg/day
                                          rodents                    Maternal LOAEL = could not be determined.
                                                                      No overt toxicity detected in dose tested
                                                                     Developmental NOAEL = 159 mg/kg/day
                                                                     Developmental LOAEL = 725 mg/kg/day based
                                                                      on decrease mean fetal body weight
----------------------------------------
870.3700                                 Prenatal developmental--    Maternal NOAEL = 158 mg/kg/day
                                          nonrodents                 Maternal LOAEL = 511 mg/kg/day based on
                                                                      decrease mean body weight
                                                                     Developmental NOAEL = 511 mg/kg/day
                                                                     Developmental LOAEL = could not be
                                                                      determined
----------------------------------------
870.3800                                 Reproduction and fertility  Parental/Systemic NOAEL = 175 (males) and
                                          effects                     244 (females) mg/kg/day
                                                                     Parental/Systemic LOAEL = could not be
                                                                      determined
                                                                     Reproductive NOAEL = 180 (males) and 212
                                                                      (females) highest dose tested (HDT) mg/kg/
                                                                      day
                                                                     Reproductive LOAEL = could not be
                                                                      determined
                                                                     Offspring NOAEL = 180 (males) and 212
                                                                      (females) HDT mg/kg/day
                                                                     Offspring LOAEL = could not be determined
----------------------------------------
870.4100                                 Chronic toxicity--rodents   NOAEL = 20 (males) and 26 (females) mg/kg/
                                                                      day
                                                                     LOAEL = 120 (males) and 133 (females) mg/kg/
                                                                      day based on decreased body weight and
                                                                      body weight gain
----------------------------------------
870.4100                                 Chronic toxicity--dogs      NOAEL = 18.75 mg/kg/day
                                                                     LOAEL = 18.75 mg/kg/day based on increased
                                                                      liver weight in high dose males and
                                                                      increased thyroid/ parathyroid-to-body
                                                                      weight ratios in females at the high dose,
                                                                      and decreased body weight and body weight
                                                                      gain in females after week 22
----------------------------------------
870.4200                                 Carcinogenicity--rats       NOAEL = 20 (males) and 26 (females) mg/kg/
                                                                      da y
                                                                     LOAEL = 120 (males) and 133 (females) mg/kg/
                                                                      day based on decreased body weight and
                                                                      body weight gain
                                                                     No evidence of carcinogenicity
----------------------------------------
870.4300                                 Carcinogenicity--mice       NOAEL = 4.3 ( females) and 979 (males) HDT
                                                                      mg/kg/da
                                                                     LOAEL = 750 mg/kg/day based on decrease in
                                                                      terminal body weights in the mid and high
                                                                      dose female mice. LOAEL could not be
                                                                      determined in males
                                                                     No evidence of carcinogenicity
----------------------------------------

[[Page 55977]]

 
870.5100                                 Gene mutation               Not mutagenic with or without metabolic
                                                                      activation in an in vitro bacterial gene
                                                                      mutation assay using Salmonella
                                                                      typhimurium
----------------------------------------
870.5300                                 Cytogenetics                Not mutagenic in the in vitro CHO/HPRT at
                                                                      concentrations up to 2,712 mg/L in Chinese
                                                                      hamster ovary cells
----------------------------------------
870.5375                                 Chromosomal aberrations     Did not induce cytogenetic damage in the
                                                                      bone marrow cells at a dose of 5,000 mg/kg
----------------------------------------
870.7485                                 Metabolism and              In the rat metabolism study most of the
                                          pharmacokinetics            radioactivity (triazine 2-\14\C was
                                                                      recovered in the urine and feces with
                                                                      almost tissue and carcass accumulation of
                                                                      radioactivity. Of the radioactivity
                                                                      eliminated in the urine and feces, most
                                                                      was parent compound with 5 minor
                                                                      metabolites
----------------------------------------------------------------------------------------------------------------

B. Toxicological Endpoints

    The dose at which no adverse effects are observed (the NOAEL) from 
the toxicology study identified as appropriate for use in risk 
assessment is used to estimate the toxicological level of concern 
(LOC). However, the lowest dose at which adverse effects of concern are 
identified (the LOAEL) is sometimes used for risk assessment if no 
NOAEL was achieved in the toxicology study selected. An uncertainty 
factor (UF) is applied to reflect uncertainties inherent in the 
extrapolation from laboratory animal data to humans and in the 
variations in sensitivity among members of the human population as well 
as other unknowns. An UF of 100 is routinely used, 10X to account for 
interspecies differences and 10X for intraspecies differences.
    Three other types of safety or uncertainty factors may be used: 
``Traditional uncertainty factors;'' the ``special FQPA safety 
factor;'' and the `` default FQPA safety factor.'' By the term 
``traditional uncertainty factor,'' EPA is referring to those 
additional uncertainty factors used prior to FQPA passage to account 
for database deficiencies. These traditional uncertainty factors have 
been incorporated by the FQPA into the additional safety factor for the 
protection of infants and children. The term`` special FQPA safety 
factor'' refers to those safety factors that are deemed necessary for 
the protection of infants and children primarily as a result of the 
FQPA. The ``default FQPA safety factor'' is the additional 10X safety 
factor that is mandated by the statute unless it is decided that there 
are reliable data to choose a different additional factor (potentially 
a traditional uncertainty factor or a special FQPA safety factor).
    For dietary risk assessment (other than cancer) the Agency uses the 
UF to calculate an acute or chronic reference dose (acute RfD or 
chronic RfD) where the RfD is equal to the NOAEL divided by an UF of 
100 to account for interspecies and intraspecies differences and any 
traditional uncertainty factors deemed appropriate (RfD = NOAEL/UF). 
Where a special FQPA safety factor or the default FQPA safety factor is 
used, this additional factor is applied to the RfD by dividing the RfD 
by such additional factor. The acute or chronic Population Adjusted 
Dose (aPAD or cPAD) is a modification of the RfD to accommodate this 
type of safety factor.
    For non-dietary risk assessments (other than cancer) the UF is used 
to determine the LOC. For example, when 100 is the appropriate UF (10X 
to account for interspecies differences and 10X for intraspecies 
differences) the LOC is 100. To estimate risk, a ratio of the NOAEL to 
exposures (margin of exposure (MOE) = NOAEL/exposure) is calculated and 
compared to the LOC.
    The linear default risk methodology (Q*) is the primary method 
currently used by the Agency to quantify carcinogenic risk. The Q* 
approach assumes that any amount of exposure will lead to some degree 
of cancer risk. A Q* is calculated and used to estimate risk which 
represents a probability of occurrence of additional cancer cases 
(e.g., risk). An example of how such a probability risk is expressed 
would be to describe the risk as one in one hundred thousand (1 X 
10-\5\), one in a million (1 X 10-\6\), or one in 
ten million (1 X 10-\7\). Under certain specific 
circumstances, MOE calculations will be used for the carcinogenic risk 
assessment. In this non-linear approach, a ``point of departure'' is 
identified below which carcinogenic effects are not expected. The point 
of departure is typically a NOAEL based on an endpoint related to 
cancer effects though it may be a different value derived from the dose 
response curve. To estimate risk, a ratio of the point of departure to 
exposure (MOEcancer = point of departure/exposures) is 
calculated.
    A summary of the toxicological endpoints for thifensulfuron methyl 
used for human risk assessment is shown in Table 2 of this unit:

Table 2.--Summary of Toxicological Dose and Endpoints for Thifensulfuron Methyl for Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
                                          Dose Used in Risk
                                             Assessment,          Special FQPA SF and
          Exposure Scenario                Interspecies and       Level of Concern for   Study and Toxicological
                                         Intraspecies and any       Risk Assessment              Effects
                                            Traditional UF
----------------------------------------------------------------------------------------------------------------
Acute Dietary (Females 13-50 years of  NOAEL = 158.9 mg/kg/day  Special FQPA SF = 1X     Developmental oral
 age)                                  UF = 100...............  aPAD = acute RfD/         toxicity study in rats
                                       Acute RfD = 1.59 mg/kg/   Special FQPA SF = 1.59  LOAEL = 725 mg/kg/day
                                        day.                     mg/kg/day.               based on decreased
                                                                                          mean fetal body weight
                                                                                          and increase in the
                                                                                          incidence of small
                                                                                          renal papillae.
--------------------------------------

[[Page 55978]]

 
Chronic Dietary (All populations)      NOAEL= 20 mg/kg/day      Special FQPA SF = 1X     Combined chronic/
                                       UF = 100...............  cPAD = chronic RfD/       carcinogenicity oral
                                       Chronic RfD = 0.20 mg/    Special FQPA SF = 0.20   toxicity in rats
                                        kg/day.                  mg/kg/day.              LOAEL = 120 (males) mg/
                                                                                          kg/day based on
                                                                                          decrease body weight
                                                                                          and body weight gain.
----------------------------------------------------------------------------------------------------------------

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. Tolerances have been 
established (40 CFR 180.439) for the residues of thifensulfuron methyl, 
in or on a variety of raw agricultural commodities. Risk assessments 
were conducted by EPA to assess dietary exposures from thifensulfuron 
methyl in food as follows:
    i. Acute exposure. Acute dietary risk assessments are performed for 
a food-use pesticide, if a toxicological study has indicated the 
possibility of an effect of concern occurring as a result of a one-day 
or single exposure.
    Dietary exposure estimates were conducted using the Lifeline model 
(Version 2.0) which incorporates consumption data from the USDA 
Continuing Surveys of Food Intakes by Individuals (CSFII), 1994-1996 
and 1998. The 1994-1996, 1998 data are based on reported consumption of 
more than 20,000 individuals over two non-consecutive survey days. 
Foods as consumed are linked to EPA-defined food commodities using 
publicly available recipe translation files (developed jointly by USDA/
ARS and EPA). Lifeline models individual dietary exposures over a 
season by selecting a new CSFII diary each day from a set of similar 
individuals, based on age and season attributes. Further information 
regarding the Lifetime model can be found at the following web site: 
http://www.LifelineTMgroup.org.
    The following assumptions were used for the acute exposure 
assessments: Tolerance level residues, 100% crop treated (CT), and 
default processing factors. Percent crop treated (PCT) or anticipated 
residues were not used.
    ii. Chronic exposure. Dietary exposure estimates were conducted 
using the Lifeline model (Version 2.0) which incorporates consumption 
data from the USDA Continuing Surveys of Food Intakes by Individuals 
(CSFII), 1994-1996 and 1998. The 1994-1996, 1998 data are based on 
reported consumption of more than 20,000 individuals over two non-
consecutive survey days. Foods as consumed are linked to EPA-defined 
food commodities using publicly available recipe translation files 
(developed jointly by USDA/ARS and EPA). Lifeline models individual 
dietary exposures over a season by selecting a new CSFII diary each day 
from a set of similar individuals, based on age and season attributes. 
The Lifeline chronic dietary exposure estimate is based on an average 
daily exposure from a profile of 1,000 individuals over a one year 
period. Further information regarding the Lifetime model can be found 
at the following web site: http://www.LifelineTMgroup.org.
    The following assumptions were used for the chronic exposure 
assessments: Tolerance level residues, 100% crop treated (CT), and 
default processing factors were used. Percent crop treated (PCT) or 
anticipated residues were not used.
    iii. Cancer. Thifensulfuron methyl has no carcinogenic potential. 
It is classified as not likely to be carcinogenic to humans based on 
the lack of evidence of carcinogenicity in both the rat and the mouse 
studies. Therefore, a cancer risk quantitative assessment was not 
performed.
    2. Dietary exposure from drinking water. The Agency lacks 
sufficient monitoring exposure data to complete a comprehensive dietary 
exposure analysis and risk assessment for thifensulfuron methyl 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 thifensulfuron methyl.
    The Agency uses the FQPA Index Reservoir Screening Tool (FIRST) or 
the Pesticide Root Zone Model/Exposure Analysis Modeling System (PRZM/
EXAMS), to produce estimates of pesticide concentrations in an index 
reservoir. The SCI-GROW model is used to predict pesticide 
concentrations in shallow ground water. For a screening-level 
assessment for surface water EPA will use FIRST (a tier 1 model) before 
using PRZM/EXAMS (a tier 2 model). The FIRST model is a subset of the 
PRZM/EXAMS model that uses a specific high-end runoff scenario for 
pesticides. Both FIRST and PRZM/EXAMS incorporate an index reservoir 
environment, and both models include a percent crop area factor as an 
adjustment to account for the maximum percent crop coverage within a 
watershed or drainage basin.
    None of these models include consideration of the impact processing 
(mixing, dilution, or treatment) of raw water for distribution as 
drinking water would likely have on the removal of pesticides from the 
source water. The primary use of these models by the Agency at this 
stage is to provide a screen for sorting out pesticides for which it is 
unlikely that drinking water concentrations would exceed human health 
levels of concern.
    Since the models used are considered to be screening tools in the 
risk assessment process, the Agency does not use estimated 
environmental concentrations (EECs), which are the model estimates of a 
pesticide's concentration in water. EECs derived from these models are 
used to quantify drinking water exposure and risk as a %RfD or %PAD. 
Instead drinking water levels of comparison (DWLOCs) are calculated and 
used as a point of comparison against the model estimates of a 
pesticide's concentration in water. DWLOCs are theoretical upper limits 
on a pesticide's concentration in drinking water in light of total 
aggregate exposure to a pesticide in food, and from residential uses. 
Since DWLOCs address total aggregate exposure to thifensulfuron methyl 
they are further discussed in the aggregate risk sections in 
Unit.III.E.
    Based on the FIRST and SCI-GROW models, the EECs of thifensulfuron 
methyl for acute exposures are estimated to be 0.331 to 4.358 part per 
billion (ppb) for surface water and 0.00002 to 0.0003 ppb for ground 
water. The EECs for chronic exposures are estimated to be 0.047 to .618 
ppb ppb for surface water and 0.00002 to 0.0003 ppb for ground water.

[[Page 55979]]

    3. 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).
    Thifensulfuron methyl is not registered for use on any sites that 
would result in residential exposure.
    4. Cumulative effects from substances with a common mechanism of 
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when 
considering whether to establish, modify, or revoke a tolerance, the 
Agency consider ``available information'' concerning the cumulative 
effects of a particular pesticide's residues and ``other substances 
that have a common mechanism of toxicity.''
    Unlike other pesticides for which EPA has followed a cumulative 
risk approach based on a common mechanism of toxicity, EPA has not made 
a common mechanism of toxicity finding as to thifensulfuron methyl and 
any other substances and thifensulfuron methyl 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 
thifensulfuron methyl has a common mechanism of toxicity with other 
substances. For information regarding EPA's efforts to determine which 
chemicals have a common mechanism of toxicity and to evaluate the 
cumulative effects of such chemicals, see the policy statements 
released by EPA's OPP concerning common mechanism determinations and 
procedures for cumulating effects from substances found to have a 
common mechanism on EPA's web site at http://www.epa.gov/pesticides/cumulative/.

D. Safety Factor for Infants and Children

    1. In general. Section 408 of FFDCA provides that EPA shall apply 
an additional tenfold margin of safety for infants and children in the 
case of threshold effects to account for prenatal and postnatal 
toxicity and the completeness of the data base on toxicity and exposure 
unless EPA determines based on reliable data that a different margin of 
safety will be safe for infants and children. Margins of safety are 
incorporated into EPA risk assessments either directly through use of a 
MOE analysis or through using uncertainty (safety) factors in 
calculating a dose level that poses no appreciable risk to humans. In 
applying this provision, EPA either retains the default value of 10X 
when reliable data do not support the choice of a different factor, or, 
if reliable data are available, EPA uses a different additional safety 
factor value based on the use of traditional uncertainty factors and/or 
special FQPA safety factors, as appropriate.
    2. Prenatal and postnatal sensitivity. The developmental rabbit and 
two generation reproductive toxicity studies suggest that there is no 
evidence of increased quantitative or qualitative susceptibility of the 
offspring after in utero or post-natal exposure to thifensulfuron 
methyl. However, the acceptable developmental toxicity study in rats 
revealed increased quantitative susceptibility of the fetus after in 
utero exposure. There are no residual uncertainties for pre and/ post 
natal toxicity because the developmental NOAEL serves as the basis for 
the acute dietary RfD. This RfD includes an uncertainty factor of 100 
and adequately addresses the concern for residual uncertainty with the 
need for an additional FQPA factor.
    3. Conclusion. There is a complete toxicity data base for 
thifensulfuron methyl and exposure data are complete or are estimated 
based on data that reasonably accounts for potential exposures. The 
impact of thifensulfuron methyl on the nervous system has not been 
specifically evaluated in neurotoxicity studies. However, no 
neuropathology or neurotoxicity was seen in either acute, subchronic, 
chronic, or reproductive studies, and there are no concerns from 
potential developmental neurotoxicity. Therefore, neurotoxicity data 
are not required for thifensulfuron methyl. EPA determined that the 10X 
SF to protect infants and children should be removed. The FQPA factor 
is removed because of the completeness of the toxicity and exposure 
database, because are no residual uncertainties for pre and/ post natal 
toxicity and because there are no concerns for potential developmental 
neurotoxicity.

E. Aggregate Risks and Determination of Safety

    To estimate total aggregate exposure to a pesticide from food, 
drinking water, and residential uses, the Agency calculates DWLOCs 
which are used as a point of comparison against EECs. DWLOC values are 
not regulatory standards for drinking water. DWLOCs are theoretical 
upper limits on a pesticide's concentration in drinking water in light 
of total aggregate exposure to a pesticide in food and residential 
uses. In calculating a DWLOC, the Agency determines how much of the 
acceptable exposure (i.e., the PAD) is available for exposure through 
drinking water e.g., allowable chronic water exposure (mg/kg/day) = 
cPAD - (average food + residential exposure). This allowable exposure 
through drinking water is used to calculate a DWLOC.
    A DWLOC will vary depending on the toxic endpoint, drinking water 
consumption, and body weights. Default body weights and consumption 
values as used by the EPA's Office of Water are used to calculate 
DWLOCs: 2 liter (L)/70 kg (adult male), 2L/60 kg (adult female), and 
1L/10 kg (child). Default body weights and drinking water consumption 
values vary on an individual basis. This variation will be taken into 
account in more refined screening-level and quantitative drinking water 
exposure assessments. Different populations will have different DWLOCs. 
Generally, a DWLOC is calculated for each type of risk assessment used: 
Acute, short-term, intermediate-term, chronic, and cancer.
    When EECs for surface water and ground water are less than the 
calculated DWLOCs, OPP concludes with reasonable certainty that 
exposures to the pesticide 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 residues of the pesticide in drinking water as a part of the 
aggregate risk assessment process.
    1. Acute risk. Using the exposure assumptions discussed in this 
unit for acute exposure, the acute dietary exposure from food to 
thifensulfuron methyl will occupy <1% of the aPAD for the U.S. 
population, <1 % of the aPAD for females 13 years and older, <1% of the 
aPAD for all infants less than one year old, and <1% of the aPAD for 
for children 1-2 years old. In addition, there is potential for acute 
dietary exposure to thifensulfuron methyl in drinking water. After 
calculating DWLOCs and comparing them to the EECs for surface and 
ground water, EPA does not expect the aggregate exposure to exceed 100% 
of the aPAD, as shown in Table 3 of this unit:

[[Page 55980]]



                 Table 3.--Aggregate Risk Assessment for Acute Exposure to Thifensulfuron Methyl
----------------------------------------------------------------------------------------------------------------
                                                                             Surface       Ground
              Population Subgroup                 aPAD (mg/      % aPAD     Water EEC    Water EEC   Acute DWLOC
                                                     kg)         (Food)       (ppb)        (ppt)        (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. Population                                     0.000514           <1        4.358        .0003       5,6000
------------------------------------------------
All infants (<1 year old                            0.000824           <1        4.358        .0003       16,000
------------------------------------------------
Children 1-2 years old                              0.000959           <1        4.358        .0003       16,000
------------------------------------------------
Children 37-5 years old                             0.000904           <1        4.358        .0003       16,000
------------------------------------------------
Females 13-59 years old                             0.000487           <1        4.358        .0003       48,000
----------------------------------------------------------------------------------------------------------------

    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that exposure to 
thifensulfuron methyl from food will utilize <1 % of the cPAD for the 
U.S. population, <1% of the cPAD for all infants less than 1 year old, 
and <1% of the cPAD for children 3-5 years old. There are no 
residential uses for thifensulfuron methyl that result in chronic 
residential exposure to thifensulfuron methyl. In addition, there is 
potential for chronic dietary exposure to thifensulfuron methyl in 
drinking water. After calculating DWLOCs and comparing them to the EECs 
for surface and ground water, EPA does not expect the aggregate 
exposure to exceed 100% of the cPAD, as shown in Table 4 of this unit:

         Table 4.--Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Thifensulfuron Methyl
----------------------------------------------------------------------------------------------------------------
                                                                             Surface       Ground
              Population Subgroup                cPAD mg/kg/     % cPAD     Water EEC    Water EEC     Chronic
                                                     day         (Food)       (ppb)        (ppb)     DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. Population                                     0.000203           <1         .618        .0003        7,000
------------------------------------------------
All Infants <1 year old                             0.000240           <1         .618        .0003        2,000
------------------------------------------------
Children 1-2 years old                              0.000410           <1         .618        .0003        2,000
------------------------------------------------
Children 3-5 years old                              0.000466           <1         .618        .0003        2,000
------------------------------------------------
Females 13-49 years old                             0.000206           <1         .618        .0003        6,000
----------------------------------------------------------------------------------------------------------------

    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).
    Thifensulfuron methyl is not registered for use on any sites that 
would result in residential exposure. Therefore, the aggregate risk is 
the sum of the risk from food and water, which do not exceed the 
Agency's level of concern.
    4. Intermediate-term risk. Intermediate-term aggregate exposure 
takes into account residential exposure plus chronic exposure to food 
and water (considered to be a background exposure level).
    Thifensulfuron methyl is not registered for use on any sites that 
would result in residential exposure. Therefore, the aggregate risk is 
the sum of the risk from food and water, which do not exceed the 
Agency's level of concern.
    5. Aggregate cancer risk for U.S. population. Thifensulfuron methyl 
has no carcinogenic potential. Therefore, the aggregate risk is the sum 
of the risk from food and water, which do not exceed the Agency`s level 
of concern.
    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 thifensulfuron methyl residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology including liquid chromatography 
with a photoconductivity detector and high-performance liquid 
chromatography with UV detector (HPLC/UV) are available for enforcement 
of the reassessed tolerances. These methods are published in PAM II.
    Adequate enforcement methodology liquid chromatography with 
detection via electospray mass spectoscopy (LC/MS) is available to 
enforce the tolerance expression for canola, flax, and cotton. The 
method may be requested from: Chief, Analytical Chemistry Branch, 
Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD 20755-5350; 
telephone number: (410) 305-2905; e-mail address: 
[email protected].

B. International Residue Limits

    There are currently no Codex maximum residue limits (MRLs) for 
thifensulfuron methyl, therefore no questions of compatibility exist. 
Mexico has established tolerances on wheat and barley at 0.05 ppm. 
Canada has established tolerances for tomato at 0.07 ppm, flax at 0.02 
ppm, and canola at 0.02 ppm. the established Mexican tolerances for 
wheat and barley are compatible with the reassessed tolerances on 
barley, grain, and wheat, grain. Canadian MRLs on flax and canola are 
compatible with the proposed tolerances of canola, seed and flax, seed.

C. Conditions

    There are no conditions of registration for either the reassessed 
tolerances or the tolerances for canola, cotton, and flax.

V. Conclusion

    Therefore, the tolerance is established for residues of 
thifensulfuron methyl,

[[Page 55981]]

methyl-3-[[[[(4-methoxy-6-methyl-1, 3, 5, -triazin-2-
yl)amino]carbonyl]amino]sulfonyl]-2-thiophenecarboxylate, in or on 
canola, seed at 0.02 ppm; cotton, gin byproducts at 0.02 ppm; cotton, 
undelinted seed at 0.02 ppm; and flax, seed at 0.02 ppm. This action 
results in the reassessment of 10 tolerances as follows: barley, grain 
at 0.05 ppm; barley, straw at 0.1 ppm; oat grain at 0.05 ppm; oat, 
straw at 0.1 ppm; soybean at 0.1 ppm; wheat, grain at 0.05 ppm; wheat, 
straw at 0.1 ppm and also three corn tolerances (corn, field, forage at 
0.1 ppm; corn, field, grain at 0.05 ppm; and corn, field, stover at 
0.10 ppm) which were inadvertently removed from 40 CFR 180. 439. On May 
12, 2004 (69 FR 26348) (FRL-7358-5), EPA proposed to reinstate the 
three corn tolerances for thifensulfuron methyl in 40 CFR 180.439. In 
the near future, EPA intends to publish the reinstatement of the corn 
tolerances for thifensulfuron methyl in the Federal Register.

VI. Objections and Hearing Requests

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

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

    You must file your objection or request a hearing on this 
regulation in accordance with the instructions provided in this unit 
and in 40 CFR part 178. To ensure proper receipt by EPA, you must 
identify docket ID number OPP-2004-0277 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 November 
16, 2004.
    1. Filing the request. Your objection must specify the specific 
provisions in the regulation that you object to, and the grounds for 
the objections (40 CFR 178.25). If a hearing is requested, the 
objections must include a statement of the factual issues(s) on which a 
hearing is requested, the requestor's contentions on such issues, and a 
summary of any evidence relied upon by the objector (40 CFR 178.27). 
Information submitted in connection with an objection or hearing 
request may be claimed confidential by marking any part or all of that 
information as CBI. Information so marked will not be disclosed except 
in accordance with procedures set forth in 40 CFR part 2. A copy of the 
information that does not contain CBI must be submitted for inclusion 
in the public record. Information not marked confidential may be 
disclosed publicly by EPA without prior notice.
    Mail your written request to: Office of the Hearing Clerk (1900L), 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001. You may also deliver your request to the 
Office of the Hearing Clerk in Suite 350, 1099 14th St., NW., 
Washington, DC 20005. The Office of the Hearing Clerk is open from 8 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
telephone number for the Office of the Hearing Clerk is (202) 564-6255.
    2. Copies for the Docket. In addition to filing an objection or 
hearing request with the Hearing Clerk as described in Unit VI.A., you 
should also send a copy of your request to the PIRIB for its inclusion 
in the official record that is described in ADDRESSES. Mail your 
copies, identified by docket ID number OPP-2004-0277, to: Public 
Information and Records Integrity Branch, Information Resources and 
Services Division (7502C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001. In person or by courier, bring a copy to the location of the 
PIRIB described in ADDRESSES. You may also send an electronic copy of 
your request via e-mail to: [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 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).

VII. Statutory and Executive Order Reviews

    This final rule establishes a tolerance under section 408(d) of 
FFDCA in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled Regulatory Planning and 
Review (58 FR 51735, October 4, 1993). Because this rule has been 
exempted from review under Executive Order 12866 due to its lack of 
significance, this rule is not subject to Executive Order 13211, 
entitled Actions Concerning Regulations That Significantly Affect 
Energy Supply, Distribution, or Use (66 FR 28355, May 22, 2001). This 
final rule does not contain any information collections subject to OMB 
approval under the Paperwork Reduction Act (PRA), 44 U.S.C. 3501 et 
seq., or impose any enforceable duty or contain any unfunded mandate as 
described under Title II of the Unfunded Mandates Reform Act of 1995 
(UMRA) (Public Law 104-4). Nor does it require any special 
considerations under Executive Order 12898, entitled Federal Actions to 
Address Environmental Justice in Minority Populations and Low-Income 
Populations (59 FR 7629, February 16, 1994); or OMB review or any 
Agency action under Executive Order 13045, entitled Protection of 
Children from Environmental Health Risks and Safety Risks (62 FR 19885, 
April 23, 1997). This action does not involve any technical standards 
that would require Agency consideration of voluntary consensus 
standards pursuant to section 12(d) of the National Technology Transfer 
and Advancement Act of 1995 (NTTAA), Public Law 104-113, section 12(d) 
(15 U.S.C. 272 note). Since tolerances and exemptions that are 
established on the basis of a petition under section 408(d) of FFDCA, 
such as the tolerance in this final rule, do not require the issuance 
of a proposed rule, the requirements of the Regulatory Flexibility Act 
(RFA) (5 U.S.C. 601 et seq.) do not apply. In addition, the Agency has 
determined that this action will not have a substantial direct effect 
on States, on the relationship between

[[Page 55982]]

the national government and the States, or on the distribution of power 
and responsibilities among the various levels of government, as 
specified in Executive Order 13132, entitled Federalism (64 FR 43255, 
August 10, 1999). Executive Order 13132 requires EPA to develop an 
accountable process to ensure ``meaningful and timely input by State 
and local officials in the development of regulatory policies that have 
federalism implications.'' ``Policies that have federalism 
implications'' is defined in the Executive order to include regulations 
that have ``substantial direct effects on the States, on the 
relationship between the national government and the States, or on the 
distribution of power and responsibilities among the various levels of 
government.'' This final rule directly regulates growers, food 
processors, food handlers and food retailers, not States. This action 
does not alter the relationships or distribution of power and 
responsibilities established by Congress in the preemption provisions 
of section 408(n)(4) of FFDCA. For these same reasons, the Agency has 
determined that this rule does not have any ``tribal implications'' as 
described in Executive Order 13175, entitled Consultation and 
Coordination with Indian Tribal Governments (65 FR 67249, November 6, 
2000). Executive Order 13175, requires EPA to develop an accountable 
process to ensure ``meaningful and timely input by tribal officials in 
the development of regulatory policies that have tribal implications.'' 
``Policies that have tribal implications'' is defined in the Executive 
order to include regulations that have ``substantial direct effects on 
one or more Indian tribes, on the relationship between the Federal 
Government and the Indian tribes, or on the distribution of power and 
responsibilities between the Federal Government and Indian tribes.'' 
This rule will not have substantial direct effects on tribal 
governments, on the relationship between the Federal Government and 
Indian tribes, or on the distribution of power and responsibilities 
between the Federal Government and Indian tribes, as specified in 
Executive Order 13175. Thus, Executive Order 13175 does not apply to 
this rule.

VIII. Congressional Review Act

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

List of Subjects in 40 CFR Part 180

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


    Dated: September 10, 2004.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

0
Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

0
1. The authority citation for part 180 continues to read as follows:

    Authority: 21 U.S.C. 321(q), 346a and 371.


0
2. Section 180.439 is revised to read as follows:


Sec.  180.439  Thifensulfuron methyl; tolerances for residues.

    (a) General. Tolerances are established for residues of the 
herbicide thifensulfuron methyl (methyl-3-[[[[(4-methoxy-6-methyl-
1,3,5-triazin-2-yl)amino] carbonyl] amino] sulfonyl]-2-thiophene 
carboxylate) in or on the following raw agricultural commodities:

------------------------------------------------------------------------
                                                                    Parts
                   Commodity                                         per
                                                                   million
----------------------------------------------------------------- ---------
Barley, grain.................................               0.05
Barley, straw.................................               0.10
Canola, seed..................................               0.02
Cotton, gin byproducts........................               0.02
Cotton, undelinted seed.......................               0.02
Flax, seed....................................               0.02
Oat, grain....................................               0.05
Oat, straw....................................               0.10
 Soybean......................................               0.10
Wheat, grain..................................               0.05
Wheat, straw..................................               0.10
------------------------------------------------------------------------

    (b) Section 18 emergency exemptions. [Reserved]
    (c) Tolerances with regional registrations. [Reserved]
    (d) Indirect or inadvertent residues. [Reserved]

[FR Doc. 04-20983 Filed 9-16-04; 8:45 am]
BILLING CODE 6560-50-S