[Federal Register: April 7, 2004 (Volume 69, Number 67)]
[Rules and Regulations]               
[Page 18255-18263]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07ap04-5]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-2003-0257; FRL-7351-4]

 
Mesosulfuron-Methyl; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This regulation establishes a tolerance for residues of 
mesosulfuron-methyl in or on wheat. Bayer CropScience requested this 
tolerance under the Federal Food, Drug, and Cosmetic Act (FFDCA), as 
amended by the Food Quality Protection Act of 1996 (FQPA).

DATES: This regulation is effective April 7, 2004. Objections and 
requests for hearings, identified by docket ID

[[Page 18256]]

number OPP-2003-0257, must be received on or before June 7, 2004.

ADDRESSES: Written objections and hearing requests may be submitted 
electronically, by mail, or through hand delivery/courier. Follow the 
detailed instructions as provided in Unit VI. of the SUPPLEMENTARY 
INFORMATION.

FOR FURTHER INFORMATION CONTACT: Jim 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 Get Copies of this Document and Other Related Information?

    1. Docket. EPA has established an official public docket for this 
action under docket identification (ID) number OPP-2003-0257. The 
official public docket consists of the documents specifically 
referenced in this action, any public comments received, and other 
information related to this action. Although a part of the official 
docket, the public docket does not include Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. The official public docket is the collection of materials 
that is available for public viewing at the Public Information and 
Records Integrity Branch (PIRI), Rm. 119, Crystal Mall 2, 1921 
Jefferson Davis Hwy., 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.
    2. Electronic access. 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 on E-CFR Beta Site 
Two at http://www.gpoaccess.gov/ecfr/. To access the OPPTS Harmonized 

Guidelines referenced in this document, go directly to the guidelines 
at http://www.epa.gov/opptsfrs/home/guidelin.htm/.

    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public 

comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Although not all docket materials may be 
available electronically, you may still access any of the publicly 
available docket materials through the docket facility identified in 
Unit I.B.1. Once in the system, select ``search,'' then key in the 
appropriate docket ID number.

II. Background and Statutory Findings

    In the Federal Register of October 22, 2003 (68 FR 60378) (FRL-
7322-5), EPA issued a notice pursuant to section 408 of FFDCA, 21 
U.S.C. 346a, as amended by FQPA (Public Law 104-170), announcing the 
filing of a pesticide petition (PP 1F6298) by Bayer CropScience, 2 T.W. 
Alexander Dr., Research Triangle Park, NC 27709. That notice included a 
summary of the petition prepared by Bayer CropScience, the registrant. 
One comment was received in response to the notice of filing from a 
private citizen.
    The petition requested that 40 CFR 180.428 be amended by 
establishing a tolerance for residues of the herbicide methyl 2-
[[[[(4,6-dimethoxy-2-pyrimidinyl) amino]carbonyl]amino]sulfonyl]-4- 
[[(methylsulfonyl)amino] methyl]benzoate, mesosulfuron-methyl, in or on 
the raw agricultural commodities wheat grain at 0.03, wheat forage at 
0.60, wheat straw at 0.30, wheat hay at 0.06, wheat germ at 0.10, 
aspirated grain fractions at 0.25, and milled byproducts at 0.03 parts 
per million (ppm). EPA determined that the tolerance for aspirated 
grain fractions should be 0.60 ppm instead of 0.25 ppm as was proposed 
by the registrant based on the results of submitted residue studies. 
Further, based on the results of submitted studies of residues in 
animal commodities, EPA determined that a tolerance should be set for 
meat byproducts of cattle, goat, horse, and sheep at the limit of 
quantitation (LOQ) for the enforcement method, which is 0.01 ppm. EPA 
also determined that no tolerance is needed for milled byproducts 
because mesosulfuron does not concentrate in milled byproducts and, 
therefore, residues in milled byproducts are covered by the tolerance 
for wheat grain.
    Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a 
tolerance (the legal limit for a pesticide chemical residue in or on a 
food) only if EPA determines that the tolerance is ``safe.'' Section 
408(b)(2)(A)(ii) of FFDCA defines ``safe'' to mean that ``there is a 
reasonable certainty that no harm will result from aggregate exposure 
to the pesticide chemical residue, including all anticipated dietary 
exposures and all other exposures for which there is reliable 
information.'' This includes exposure through drinking water and in 
residential settings, but does not include occupational exposure. 
Section 408(b)(2)(C) of FFDCA requires EPA to give special 
consideration to exposure of infants and children to the pesticide 
chemical residue in establishing a tolerance and to ``ensure that there 
is a reasonable certainty that no harm will result to infants and 
children from aggregate exposure to the pesticide chemical 
residue....''
    EPA performs a number of analyses to determine the risks from 
aggregate exposure to pesticide residues. For further discussion of the 
regulatory requirements of section 408 of FFDCA and a complete 
description of the risk assessment process, see the final rule on 
Bifenthrin Pesticide Tolerances (62 FR 62961, November 26, 1997) (FRL-
5754-7).

III. Aggregate Risk Assessment and Determination of Safety

    Consistent with section 408(b)(2)(D) of FFDCA, EPA has reviewed the 
available scientific data and other relevant information in support of 
this

[[Page 18257]]

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 mesosulfuron-methyl on the 
raw agricultural commodities aspirated grain fractions at 0.60 ppm, 
meat byproducts of cattle, goat, horse, and sheep meat byproducts at 
0.01 ppm, wheat forage at 0.60 ppm, wheat germ at 0.10 ppm, wheat grain 
at 0.03 ppm, wheat hay at 0.06 ppm, and wheat straw at 0.30 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 mesosulfuron-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.--Toxicology Profile for Mesosulfuron-Methyl
------------------------------------------------------------------------
         Guideline No.              Study Type            Results
------------------------------------------------------------------------
870.3100                        90-Day oral        NOAEL = 908/977 Male/
                                 toxicity rodents   Female (M/F)
                                                    milligram/kilogram/
                                                    day (mg/kg/day)
                                                   LOAEL = not observed.
---------------------------------------------------

-------------------------------
870.3150                        90-Day oral        NOAEL = 648/734 M/F
                                 toxicity in        mg/kg/day
                                 nonrodents        LOAEL = not observed.
-------------------------------
870.3200                        21/28-Day dermal   Study not required.
                                 toxicity
-------------------------------
870.3250                        90-Day dermal      Study not required.
                                 toxicity
-------------------------------
870.3465                        90-Day inhalation  Study not required.
                                 toxicity
-------------------------------
870.3700                        Prenatal           Maternal NOAEL =
                                 developmental in   1,000 mg/kg/day
                                 rodents           LOAEL = not observed
                                                   Developmental NOAEL =
                                                    1,000 mg/kg/day
                                                   LOAEL = not observed
-------------------------------
870.3700                        Prenatal           Maternal NOAEL =
                                 developmental in   1,000 mg/kg/day
                                 nonrodents        LOAEL = not observed
                                                   Developmental NOAEL =
                                                    1,000 mg/kg/day
                                                   LOAEL = not observed
-------------------------------
870.3800                        Reproduction and   Parental/Systemic
                                 fertility          NOAEL = 1,175.2/
                                 effects            1,387.6 M/F mg/kg/
                                                    day
                                                   LOAEL = not observed
                                                   Reproductive NOAEL =
                                                    1,175.2/ 1,387.6 M/F
                                                    mg/kg/day
                                                   LOAEL = not observed
                                                   Offspring NOAEL =
                                                    1,175.2/ 1,387.6 M/F
                                                    mg/kg/day
                                                   LOAEL = not observed
-------------------------------
870.4100                        Chronic toxicity   NOAEL = 764/ 952 M/F
                                 rodents            mg/kg/day
                                                   LOAEL = not observed.
-------------------------------
870.4100                        Chronic toxicity   NOAEL = 155 M mg/kg/
                                 dogs               day
                                                   LOAEL = 574 M mg/kg/
                                                    day based on
                                                    increased mucus
                                                    secretion in the
                                                    cardiac and fundic
                                                    sections of the
                                                    stomach of the males
                                                    dogs (highest dose
                                                    tested (HDT)) and
                                                    chronic superficial
                                                    gastritis (1/6).
-------------------------------
870.4200                        Carcinogenicity    NOAEL = 764/952 M/F
                                 rats               mg/kg/day
                                                   LOAEL = not observed.
                                                   (no) evidence of
                                                    carcinogenicity
-------------------------------
870.4300                        Carcinogenicity    NOAEL = 1,069.4/
                                 mice               1,355.6 M/F mg/kg/
                                                    day
                                                   LOAEL = not observed.
                                                   (no) evidence of
                                                    carcinogenicity
-------------------------------
870.5100                        Bacterial reverse  Negative  S9
                                                    up to cytotoxic
                                                    5,000 [mu]gram (g)/
                                                    milliliter (ml)
                                                    plate
-------------------------------
870.5300                        Mammalian cell     Negative  S9
                                                    up to cytotoxic
                                                    2,500 [mu]g/ml and
                                                    precipitation 250
                                                    [mu]g/ml
-------------------------------
870.5395                        Micronucleus test  Negative at the HDT
Cytogenetics..................   on mouse           (limit dose) 2,000
                                                    mg/kg.
-------------------------------

[[Page 18258]]


870.5375                        Chromosomal        Negative  S9
                                                    precipitation =100 [mu]g/ml
-------------------------------
870.5550                        Unscheduled DNA    Negative  S9
                                                    precipitation =100 [mu]g/ml
-------------------------------
870.6200                        Acute              Study not required.
                                 neurotoxicity
                                 screening
                                 battery
-------------------------------
870.6200                        Subchronic         Study not required.
                                 neurotoxicity
                                 screening
                                 battery
-------------------------------
870.6300                        Developmental      Study not required.
                                 neurotoxicity
-------------------------------
870.7485                        Metabolism and     Overall recovery of
                                 pharmacokinetics   the radioactive dose
                                                    was 98-103%,
                                                    predominantly
                                                    recovered in the
                                                    feces within 24
                                                    hours (80-97% dose).
                                                    The onset of
                                                    absorption was quick
                                                    (detected in the
                                                    blood 15 minutes
                                                    post-dose), but the
                                                    quantity absorbed
                                                    was low. At 72 hours
                                                    post-dose (or 168
                                                    hours following the
                                                    final dose of the
                                                    repeated study),
                                                    urinary excretion
                                                    accounted for 1-4%
                                                    (except 13-14% in
                                                    the 10 mg/kg
                                                    animals), and
                                                    radioactivity in the
                                                    bile of the 10 mg/kg
                                                    animals was only 7-
                                                    9% dose by 12 hours
                                                    post-dose. The 10 mg/
                                                    kg rats had slightly
                                                    more radioactivity
                                                    in urine and
                                                    slightly less
                                                    radioactivity in
                                                    feces compared to
                                                    the 1,000 mg/kg
                                                    rats.
                                                    Bioaccumulation was
                                                    not observed, and
                                                    radioactivity in
                                                    tissues was <0.1%
                                                    dose in all animals
                                                    at each study
                                                    termination.
-------------------------------
870.7600                        Dermal             100% dermal
                                 penetration        absorption factor
                                                    (default value)
-------------------------------
Special studies                                    Study not required.
------------------------------------------------------------------------

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 mesosulfuron-methyl 
used for human risk assessment is shown in Table 2 of this unit:


[[Page 18259]]



 Table 2.--Summary of Toxicological Doses and Endpoints for Mesosulfuron-Methyl for Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
                                                                  Special FQPA SF* and
          Exposure Scenario               Dose Used in Risk       Level of Concern for   Study and Toxicological
                                            Assessment, UF          Risk Assessment              Effects
----------------------------------------------------------------------------------------------------------------
Acute Dietary:                          No study in the toxicology database indicated there is an acute dietary
(All populations)....................                             endpoint of concern.
--------------------------------------
Chronic Dietary:                       NOAEL= 155 mg/kg/day     FQPA SF = 1X             Chronic oral toxicity
(All populations)....................  UF = 100...............  cPAD = chronic RfD/FQPA   study in dogs.
                                       Chronic RfD = 1.55 mg/    SF = 1.55 mg/kg/day.    LOAEL = 574 mg/kg/day
                                        kg/day.                                           [M] based on increased
                                                                                          mucus secretion in the
                                                                                          cardiac and fundic
                                                                                          sections of the
                                                                                          stomach, and chronic
                                                                                          superficial gastritis
                                                                                          (1/6) of male dogs.
--------------------------------------
Incidental Oral:                               No residential uses are proposed for mesosulfuron-methyl.
(Short- and Intermediate-Term).......
--------------------------------------
Dermal Exposure:                        Quantification of dermal risk is not required for this route of exposure
(Short-, Intermediate-, and Long-         due to the lack of dermal, systemic, neurological, and developmental
 Term).                                                            toxicity concerns.
--------------------------------------
Inhalation Exposure:                   Oral                     Residential LOC for MOE  Chronic oral toxicity
(Short-, Intermediate-, and Long-      NOAEL= 155 mg/kg/day      = NA                     study in dogs.
 Term).                                 (100% Oral Absorption   Occupational LOC for     LOAEL = 574 mg/kg/day
                                        Factor).                 MOE = 100.               [M] based on increased
                                                                                          mucus secretion in the
                                                                                          cardiac and fundic
                                                                                          sections of the
                                                                                          stomach, and chronic
                                                                                          superficial gastritis
                                                                                          (1/6) of male dogs.
--------------------------------------
Cancer:                                ``Not likely to be carcinogenic to humans'' based on the lack of evidence
(Oral, Dermal, and Inhalation).......                   of carcinogenicity in the rats and mice.
----------------------------------------------------------------------------------------------------------------
UF = uncertainty factor, FQPA SF = Special FQPA safety factor, NOAEL = no-observed-adverse-effect-level, LOAEL =
  lowest-observed-adverse-effect-level, PAD = population adjusted dose (a = acute, c = chronic), RfD = reference
  dose, MOE = margin of exposure, LOC = level of concern, NA = Not Applicable.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. Tolerances have been 
proposed wheat and meat byproducts of cattle, goat, horse, and sheep. 
Risk assessments were conducted by EPA to assess dietary exposures from 
mesosulfuron-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 1-day or 
single exposure.
    Based on available data, a suitable endpoint for acute dietary risk 
assessment was not identified because no effects were observed in oral 
toxicity studies (including developmental studies) which could be 
attributed to a single-dose exposure. Therefore, an acute dietary risk 
assessment was not performed.
    ii. Chronic exposure. In conducting the chronic dietary risk 
assessment EPA used the Dietary Exposure Evaluation Model software with 
the Food Commodity Intake Database (DEEM-FCID\T\) and the Lifeline\T\ 
Model Version 2.0,, which incorporates food consumption data as 
reported by respondents in the USDA 1994-1996 and 1998 Nationwide 
Continuing Surveys of Food Intake by Individuals (CSFII), and 
accumulated exposure to the chemical for each commodity. The following 
assumptions were made for the chronic exposure assessments: tolerance 
level residues, default processing factors, and 100% crop treated data, 
with no refinements.
    iii. Cancer. A quantitative cancer dietary exposure cancer dietary 
assessment was not conducted because mesosulfuron-methyl was classified 
as ``not likely to be carcinogenic to humans.''
    2. Dietary exposure from drinking water. The Agency lacks 
sufficient monitoring exposure data to complete a comprehensive dietary 
exposure analysis and risk assessment for mesosulfuron-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 mesosulfuron-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

[[Page 18260]]

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 mesosulfuron-
methyl they are further discussed in the aggregate risk sections in 
Unit III.E.
    EPA determined that three degradates may be present at sufficient 
quantities (found in aerobic soil and aerobic and anaerobic aquatic 
environments at levels ranging from 5% to 20% of the applied dose) to 
warrant inclusion in the drinking water assessment. The three 
degradates are 2-[3-(4,6-dimethoxypyrimidin-2-yl)ureidosulfonyl]-4-
methanesulfonamidomethyl benzoic acid (AE F154851), methyl-2-[3-(4-
hydroxy-6-methoxypyrimidin-2-yl)ureidosulfonyl]-4-
methanesulfonamidomethylbenzoate (AE F160459), and 2-[3-(4-hydroxy-6-
methoxypyrimidine-2-yl)ureidosulfonyl]-4-methanesulfonamidomethyl 
benzoic acid (AE F160460). EPA determined that these degradates were 
not of concern for food due to low toxicity and low level of exposure 
in food, and that, for food, parent mesosulfuron-methyl is the only 
residue of concern.
    Based on the FIRST and SCI-GROW models, the EECs of mesosulfuron-
methyl and its degradates for chronic exposures are estimated to be 
0.15 parts per billion (ppb) for surface water and 0.015 ppb for ground 
water.
    3. From non-dietary exposure. The term ``residential exposure'' is 
used in this document to refer to non-occupational, non-dietary 
exposure (e.g., for lawn and garden pest control, indoor pest control, 
termiticides, and flea and tick control on pets).
    Mesosulfuron-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 mesosulfuron-methyl and 
any other substances and mesosulfuron-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 
mesosulfuron-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 10 X 
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. There are no concerns or 
residual uncertainties for pre- and/or post-natal toxicity.
    3. Conclusion. There is a complete toxicity data base for 
mesosulfuron-methyl and exposure data are complete or are estimated 
based on data that reasonably accounts for potential exposures. EPA 
determined that the 10X FQPA safety factor to protect infants and 
children should be removed. The FQPA factor is removed because:
    i. There is no evidence of increased quantitative/qualitative 
susceptibility in the available acceptable guideline studies.
    ii. There are no residual uncertainties for pre- and/or post-natal 
toxicity.
    iii. Clear NOAELs have been identified for the effects of concern.
    iv. No adverse effects were noted at the highest dose tested in the 
acceptable guideline developmental toxicity and reproduction studies in 
rats, and developmental toxicity study in rabbits.
    v. There are no proposed residential uses.

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.

[[Page 18261]]

    1. Acute risk. Based on available data, a suitable endpoint for 
acute dietary risk assessment was not identified because no effects 
were observed in oral toxicity studies (including developmental 
studies) which could be attributed to a single-dose exposure. 
Therefore, mesosulfuron-methyl is not expected to pose an acute dietary 
risk.
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that exposure to 
mesosulfuron-methyl from food will utilize <1% of the cPAD for the U.S. 
population, <1% of the cPAD for infants < 1 year old, and <1% of the 
cPAD for children 1-12. There are no residential uses for mesosulfuron-
methyl that result in chronic residential exposure to mesosulfuron-
methyl. In addition, there is potential for chronic dietary exposure to 
mesosulfuron-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 3 of this unit:


          Table 3.--Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Mesosulfuron-Methyl
----------------------------------------------------------------------------------------------------------------
                                                                             Surface       Ground
              Population Subgroup                cPAD mg/kg/     % cPAD     Water EEC    Water EEC     Chronic
                                                     day         (Food)       (ppb)        (ppb)     DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
General U.S. Population                                 1.55           <1        0.154        0.015       54,000
------------------------------------------------
All Infants (< 1 year old)                              1.55           <1        0.154        0.015       16,000
------------------------------------------------
Children 1-2 years old                                  1.55           <1        0.154        0.015       16,000
------------------------------------------------
Children 3-5 years old                                  1.55           <1        0.154        0.015       16,000
------------------------------------------------
Children 6-12 years old                                 1.55           <1        0.154        0.015       16,000
------------------------------------------------
Youth 13-19 years old                                   1.55           <1        0.154        0.015       47,000
------------------------------------------------
Females 13-49 years old                                 1.55           <1        0.154        0.015       47,000
------------------------------------------------
Adults 20-49 years old                                  1.55           <1        0.154        0.015       54,000
----------------------------------------------------------------------------------------------------------------


    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).
    Mesosulfuron-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).
    Mesosulfuron-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. The EPA classified 
mesosulfuron-methyl as ``not likely to be carcinogenic to humans.'' 
Therefore, mesosulfuron-methyl is not expected to pose a cancer risk.
    6. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to the general population, and to infants and children from aggregate 
exposure to mesosulfuron-methyl residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Method EM F08/99-0 (liquid chromatography/mass spectroscopy/mass 
spectroscopy ) is adequate for tolerance enforcement for mesosulfuron-
methyl in plant commodities. The method has been subjected to 
successful independent laboratory validations (ILVs), satisfactory 
radiovalidation data have been submitted, and the method has been 
reviewed by an EPA chemist.
    Method EM F07/00-0 (liquid chromatography/mass spectroscopy/mass 
spectroscopy) is adequate for tolerance enforcement for mesosulfuron-
methyl in livestock commodities. The method has been reviewed by an EPA 
chemist. Although there has been no independent lab validation of this 
method in animal commodities, EPA determined that independent lab 
validation is not necessary because:
    1. This method (F07/00-0) is essentially identical to the plant 
method (EM F08/99-0), which was succesfully validated in an independent 
laboratory, and
    2. EPA has previously validated single-analyte methods for members 
of this class of chemicals which use similar extraction and cleanup 
procedures.
Both methods 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, Canadian, or Mexican MRL's or 
tolerances for mesosulfuron-methyl on wheat.

C. Conditions

    The following are being imposed as conditions of registration of 
mesosulfuron-methyl:
     A one year storage stability (guideline 
830.6317) and corrosion characteristics (guideline 830.6320) must be 
submitted to EPA by October 1, 2005.
     Storage stability data must be submitted to 
demonstrate the stability of mesosulfuron-methyl residues in/on wheat 
forage stored frozen for up to 26 months and in/on wheat grain and 
straw stored frozen for up to 25 months by October 1, 2005.

D. Response to Comments

    The one comment received on the tolerance petition stated: ``I 
oppose any tolerance allowance granted for mesosulfuron-methyl on any 
food product. I am totally against any chemicals in the food I eat. I 
do not think we should allow these chemical polluters in our food. I 
know industry waves lots of money to get these

[[Page 18262]]

approvals. The American public disapproves of EPA granting these. EPA 
is even being sued for these approvals. I am totally against granting 
approval of this pesticide on any food in any amount at all. I prefer 
zero tolerance.''
    Response: This commenter has a disagreement not with how EPA is 
implementing FFDCA section 408 as it applies to the tolerance petition 
on mesosulfuron-methyl but with FFDCA section 408 itself. The 
commenter--and in the commenter's view the general American public as 
well--would prefer that FFDCA section 408 bar the establishment of any 
tolerance permitting any pesticide residues to remain on food. That, 
however, is not the law. Rather, FFDCA section 408 as it is currently 
written establishes a safety standard under which EPA must evaluate 
petitions to establish tolerances. EPA has applied that safety standard 
in ruling on the mesosulfuron-methyl tolerance petition. EPA cannot 
take a commenter's policy preference on what the FFDCA should say into 
account in ruling on application of the FFDCA to a particular 
situation.

V. Conclusion

    Therefore, the tolerance is established for residues of methyl 2-
[[[[(4,6-dimethoxy-2-pyrimidinyl) amino]carbonyl]amino] sulfonyl]-4-
[[(methylsulfonyl)amino] methyl]benzoate]], mesosulfuron-methyl, in or 
on the raw agricultural commodities aspirated grain fractions at 0.60 
ppm; meat byproducts of cattle, goat, horse, and sheep at 0.01 ppm; 
wheat forage at 0.60 ppm; wheat germ at 0.10 ppm; wheat grain at 0.03 
ppm; wheat hay at 0.06 ppm; and wheat straw at 0.30 ppm.

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-2003-0257 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 June 7, 
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 (1900C), 
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 Rm.104, Crystal Mall 2, 1921 
Jefferson Davis Hwy., Arlington, VA. 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 
(703) 603-0061.
    2. Tolerance fee payment. If you file an objection or request a 
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or 
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must 
mail the fee to: EPA Headquarters Accounting Operations Branch, Office 
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please 
identify the fee submission by labeling it ``Tolerance Petition Fees.''
    EPA is authorized to waive any fee requirement ``when in the 
judgement of the Administrator such a waiver or refund is equitable and 
not contrary to the purpose of this subsection.'' For additional 
information regarding the waiver of these fees, you may contact James 
Tompkins by phone at (703) 305-5697, by e-mail at tompkins.jim@epa.gov, 
or by mailing a request for information to Mr. Tompkins at Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001.
    If you would like to request a waiver of the tolerance objection 
fees, you must mail your request for such a waiver to: James Hollins, 
Information Resources and Services Division (7502C), Office of 
Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460-0001.
    3. 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 Unit I.B.1. Mail your 
copies, identified by docket ID number OPP-2003-0257, 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 Unit I.B.1. You may also send an electronic copy of 
your request via e-mail to: opp-docket@epa.gov. Please use an ASCII 
file format and avoid the use of special characters and any form of 
encryption. Copies of electronic objections and hearing requests will 
also be accepted on disks in WordPerfect 6.1/8.0 or ASCII file format. 
Do not include any CBI in your electronic copy. You may also submit an 
electronic copy of your request at many Federal Depository Libraries.

B. When Will the Agency Grant a Request for a Hearing?

    A request for a hearing will be granted if the Administrator 
determines that the material submitted shows the following: There is a 
genuine and substantial issue of fact; there is a reasonable 
possibility that available evidence identified by the requestor would, 
if established resolve one or more of such issues in favor of the 
requestor, taking into account uncontested claims or facts to the 
contrary; and resolution of the factual issues(s) in the manner sought 
by the requestor would be adequate to justify the action requested (40 
CFR 178.32).

[[Page 18263]]

VII. Statutory and Executive Order Reviews

    This final rule establishes a tolerance under section 408(d) of 
FFDCA in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled Regulatory Planning and 
Review (58 FR 51735, October 4, 1993). Because this rule has been 
exempted from review under Executive Order 12866 due to its lack of 
significance, this rule is not subject to Executive Order 13211, 
Actions Concerning Regulations That Significantly Affect Energy Supply, 
Distribution, or Use (66 FR 28355, May 22, 2001). This final rule does 
not contain any information collections subject to OMB approval under 
the Paperwork Reduction Act (PRA), 44 U.S.C. 3501 et seq., or impose 
any enforceable duty or contain any unfunded mandate as described under 
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA) (Public Law 
104-4). Nor does it require any special considerations under Executive 
Order 12898, entitled Federal Actions to Address Environmental Justice 
in Minority Populations and Low-Income Populations (59 FR 7629, 
February 16, 1994); or OMB review or any Agency action under Executive 
Order 13045, entitled Protection of Children from Environmental Health 
Risks and Safety Risks (62 FR 19885, April 23, 1997). This action does 
not involve any technical standards that would require Agency 
consideration of voluntary consensus standards pursuant to section 
12(d) of the National Technology Transfer and Advancement Act of 1995 
(NTTAA), Public Law 104-113, section 12(d) (15 U.S.C. 272 note). Since 
tolerances and exemptions that are established on the basis of a 
petition under section 408(d) of FFDCA, such as the tolerance in this 
final rule, do not require the issuance of a proposed rule, the 
requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et 
seq.) do not apply. In addition, the Agency has determined that this 
action will not have a substantial direct effect on States, on the 
relationship between the national government and the States, or on the 
distribution of power and responsibilities among the various levels of 
government, as specified in Executive Order 13132, entitled Federalism 
(64 FR 43255, August 10, 1999). Executive Order 13132 requires EPA to 
develop an accountable process to ensure ``meaningful and timely input 
by State and local officials in the development of regulatory policies 
that have federalism implications.'' ``Policies that have federalism 
implications'' is defined in the Executive order to include regulations 
that have ``substantial direct effects on the States, on the 
relationship between the national government and the States, or on the 
distribution of power and responsibilities among the various levels of 
government.'' This final rule directly regulates growers, food 
processors, food handlers and food retailers, not States. This action 
does not alter the relationships or distribution of power and 
responsibilities established by Congress in the preemption provisions 
of section 408(n)(4) of FFDCA. For these same reasons, the Agency has 
determined that this rule does not have any ``tribal implications'' as 
described in Executive Order 13175, entitled Consultation and 
Coordination with Indian Tribal Governments (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: March 26, 2004.
James Jones,
Director, 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 180.597 is added to read as follows:


Sec.  180.597  Mesosulfuron-methyl; tolerances for residues.

    (a) General. Tolerances are established for residues of the 
herbicide mesosulfuron-methyl, (methyl 2-[[[[ (4,6-dimethoxy-2-
pyrimidinyl) amino]carbonyl]amino]sulfonyl] -4-[[(methylsulfonyl)amino] 
methyl]benzoate]) in or on the following raw agricultural commodities:

------------------------------------------------------------------------
                                                              Parts per
                         Commodity                             million
------------------------------------------------------------------------
Cattle, meat byproducts....................................         0.01
Goat, meat byproducts......................................         0.01
Grain, aspirated fractions                                          0.60
Horse, meat byproducts.....................................         0.01
Sheep, meat byproducts.....................................         0.01
Wheat, forage..............................................         0.60
Wheat, germ................................................         0.10
Wheat, grain...............................................         0.03
Wheat, hay.................................................         0.06
Wheat, straw...............................................         0.30
------------------------------------------------------------------------

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

[FR Doc. 04-7781 Filed 4-6-04; 8:45 am]

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