[Federal Register: September 17, 2004 (Volume 69, Number 180)]
[Rules and Regulations]
[Page 55975-55982]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr17se04-11]
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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:
tompkins.jim@epa.gov.
SUPPLEMENTARY INFORMATION:
I. General Information
A. Does this Action Apply to Me?
You may be potentially affected by this action if you are an
agricultural producer, food manufacturer, or pesticide manufacturer.
Potentially affected entities may include, but are not limited to:
Crop production (NAICS 111), e.g., agricultural workers;
greenhouse, nursery, and floriculture workers; farmers.
Animal production (NAICS 112), e.g., cattle ranchers and
farmers, dairy cattle farmers, livestock farmers.
Food manufacturing (NAICS 311), e.g., agricultural
workers; farmers; greenhouse, nursery, and floriculture workers;
ranchers; pesticide applicators.
Pesticide manufacturing (NAICS 32532), e.g., agricultural
workers; commercial applicators; farmers; greenhouse, nursery, and
floriculture workers; residential users.
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
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Guideline No. Study Type Results
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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
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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
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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.
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[[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:
residuemethods@epa.gov.
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: opp-docket@epa.gov. Please use an ASCII
file format and avoid the use of special characters and any form of
encryption. Copies of electronic objections and hearing requests will
also be accepted on disks in WordPerfect 6.1/8.0 or ASCII file format.
Do not include any CBI in your electronic copy. You may also submit an
electronic copy of your request at many Federal Depository Libraries.
B. When Will the Agency Grant a Request for a Hearing?
A request for a hearing will be granted if the Administrator
determines that the material submitted shows the following: There is a
genuine and substantial issue of fact; there is a reasonable
possibility that available evidence identified by the requestor would,
if established resolve one or more of such issues in favor of the
requestor, taking into account uncontested claims or facts to the
contrary; and resolution of the factual issues(s) in the manner sought
by the requestor would be adequate to justify the action requested (40
CFR 178.32).
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