Document ID: EPA-HQ-OPP-2010-0267-0003
Agency: epa
Document Type: Rule
Title: Pesticide Tolerances: Mefenpyr-diethyl
Posted Date: 2011-04-29T04:00Z

[Federal Register Volume 76, Number 83 (Friday, April 29, 2011)]
[Rules and Regulations]
[Pages 23898-23903]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-10439]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2010-0267; FRL-8870-9]

Mefenpyr-diethyl; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for residues of 
mefenpyr-diethyl in or on multiple commodities. Bayer CropScience LLC 
requested these tolerances under the Federal Food, Drug, and Cosmetic 
Act (FFDCA). This regulation also moves established tolerances for 
canola and soybean commodities to correct an administrative error.

DATES: This regulation is effective April 29, 2011. Objections and 
requests for hearings must be received on or before June 28, 2011, and 
must be filed in accordance with the instructions provided in 40 CFR 
part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION ).

ADDRESSES: EPA has established a docket for this action under docket 
identification (ID) number EPA-HQ-OPP-2010-0267. All documents in the 
docket are listed in the docket index available at http://www.regulations.gov. Although listed in the index, some information is 
not publicly available, e.g., Confidential Business Information (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 in the electronic 
docket at http://www.regulations.gov, or, if only available in hard 
copy, at the OPP Regulatory Public Docket in Rm. S-4400, One Potomac 
Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The Docket 
Facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. The Docket Facility telephone number is (703) 
305-5805.

FOR FURTHER INFORMATION CONTACT: Bethany Benbow, Registration Division 
(7505P), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 347-8072; e-mail address: benbow.bethany@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 those 
engaged in the following activities:
     Crop production (NAICS code 111).
     Animal production (NAICS code 112).
     Food manufacturing (NAICS code 311).
     Pesticide manufacturing (NAICS code 32532).
    This listing is not intended to be exhaustive, but rather to 
provide 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 electronic access to other related information?

    You may access a frequently updated electronic version of EPA's 
tolerance regulations at 40 CFR part 180 through the Government 
Printing Office's e-CFR site at http://www.gpoaccess.gov/ecfr.

C. How can I file an objection or hearing request?

    Under FFDCA section 408(g), 21 U.S.C. 346a, any person may file an 
objection to any aspect of this regulation and may also request a 
hearing on those objections. You must file your objection or request a 
hearing on this regulation in accordance with the instructions provided 
in 40 CFR part 178. To ensure proper receipt by EPA, you must identify 
docket ID number EPA-HQ-

[[Page 23899]]

OPP-2010-0267 in the subject line on the first page of your submission. 
All objections and requests for a hearing must be in writing, and must 
be received by the Hearing Clerk on or before June 28, 2011. Addresses 
for mail and hand delivery of objections and hearing requests are 
provided in 40 CFR 178.25(b).
    In addition to filing an objection or hearing request with the 
Hearing Clerk as described in 40 CFR part 178, please submit a copy of 
the filing that does not contain any CBI for inclusion in the public 
docket. Information not marked confidential pursuant to 40 CFR part 2 
may be disclosed publicly by EPA without prior notice. Submit a copy of 
your non-CBI objection or hearing request, identified by docket ID 
number EPA-HQ-OPP-2010-0267, by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     Mail: Office of Pesticide Programs (OPP) Regulatory Public 
Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460-0001.
     Delivery: OPP Regulatory Public Docket (7502P), 
Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South 
Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only 
accepted during the Docket Facility's normal hours of operation (8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays). 
Special arrangements should be made for deliveries of boxed 
information. The Docket Facility telephone number is (703) 305-5805.

II. Summary of Petitioned-For Tolerance

    In the Federal Register of June 23, 2010 (75 FR 35804) (FRL-8831-
3), 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 
9F7679) by Bayer CropScience LLC, 2 T.W. Alexander Drive, Research 
Triangle Park, NC 27709. The petition requested that 40 CFR 180.509 be 
amended by establishing tolerances for residues of the herbicide 
safener, mefenpyr-diethyl including its metabolites and degradates with 
compliance to be determined by measuring residues of mefenpyr-diethyl, 
(1-(2,4-dichlorophenyl)-4,5-dihydro-5-methyl-1H-pyrazole-3,5-
dicarboxylic acid, diethyl ester) and its dichlorophenyl-pyrazoline 
metabolites, in or on grass, forage at 1.5 parts per million (ppm); 
grass, hay at 0.05 ppm; sorghum, forage at 0.1 ppm; sorghum, grain at 
0.01 ppm; and sorghum, stover at 0.05 ppm. That notice referenced a 
summary of the petition prepared by Bayer CropScience LLC, the 
registrant, which is available in the docket, http://www.regulations.gov. There were no comments received in response to the 
notice of filing.
    Based upon review of the data supporting the petition, EPA has 
increased the proposed tolerance for all proposed commodities as 
follows: Grass, forage from 1.5 to 1.6 ppm; grass, hay from 0.05 to 0.2 
ppm; sorghum, forage from 0.1 to 0.4 ppm; sorghum, grain from 0.01 to 
0.04 ppm; and sorghum, stover from 0.05 to 0.2 ppm. The reasons for 
these changes are explained in Unit IV.C.
    In the Federal Register of December 10, 2008 (73 FR 74977) (FRL-
8390-8), EPA established tolerances for residues of mefenpyr-diethyl in 
or on canola, seed; soybean, forage; soybean, hay; and soybean, seed. 
These tolerances were identified as rotational crop tolerances in the 
final rule; however, they were placed in paragraph (a) of 40 CFR 
180.509 in error. They should have been placed in paragraph (d) as 
tolerances for indirect or inadvertent residues. EPA is moving these 
tolerances from paragraph (a) to paragraph (d) to correct this 
administrative error. Moving these tolerances between subsections has 
no substantive effect, it merely makes them easier to identify as 
rotational crop tolerances.

III. Aggregate Risk Assessment and Determination of Safety

    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. * * 
*''
    Consistent with section 408(b)(2)(D) of FFDCA, and the factors 
specified in 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 for mefenpyr-diethyl 
including exposure resulting from the tolerances established by this 
action. EPA's assessment of exposures and risks associated with 
mefenpyr-diethyl 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.
    Mefenpyr-diethyl has low acute toxicity by the oral, dermal, and 
inhalation routes of exposure. It is not a dermal irritant but is a 
slight ocular irritant and dermal sensitizer. Repeated exposure of rats 
via the dermal route did not induce any treatment-related effects at 
dose levels up to and including the limit dose. Repeated exposure 
studies via the oral route demonstrate that the target organs are the 
liver and hematopoietic system in dogs, mice, and rats. Effects 
observed in dogs included increased liver weight and alkaline 
phosphatase activity (both sexes), focal liver lesions (females), 
slight anemia (both sexes), decreased mean body weight and body weight 
gain (females) and decreased food consumption (both sexes). Effects 
observed in mice included decreased body weight and kidney weight, 
increased liver weight, and hepatocyte hypertrophy (males), as well as 
decreased bilirubin and increased lactic acid dehydrogenase values 
(females). Effects observed in rats included increases in reticulocyte 
counts (both sexes), and decreased red blood count, hemoglobin, and 
hematocrit values (females). Mefenpyr-diethyl was negative for 
carcinogenicity in rats and mice, and is classified as ``not likely to 
be carcinogenic to humans.'' The available studies did not indicate any 
genotoxic or neurotoxic potential. Developmental toxicity was not 
observed in the rat but was observed in the rabbit (abortions) at the 
same dose level producing maternal toxicity. Mefenpyr-diethyl did not 
induce any signs of reproductive toxicity. The developmental toxicity 
studies in rats and rabbits, as well as the reproductive toxicity study 
in rats, did not demonstrate any pre- or post-natal sensitivity.

[[Page 23900]]

    Specific information on the studies received and the nature of the 
adverse effects caused by mefenpyr-diethyl as well as the no-observed-
adverse-effect-level (NOAEL) and the lowest-observed-adverse-effect-
level (LOAEL) from the toxicity studies can be found at http://www.regulations.gov in document, Mefenpyr-diethyl (HOE 107892) Safener: 
Revised Human Health Risk Assessment to Support the New use Petition on 
Sorghum [grain, stover, and forage] and Grass Grown for Seed (including 
Conservation Reserve Program areas), at pages 31-36 in docket ID number 
EPA-HQ-OPP-2010-0267.

B. Toxicological Points of Departure/Levels of Concern

    Once a pesticide's toxicological profile is determined, EPA 
identifies toxicological points of departure (POD) and levels of 
concern to use in evaluating the risk posed by human exposure to the 
pesticide. For hazards that have a threshold below which there is no 
appreciable risk, the toxicological POD is used as the basis for 
derivation of reference values for risk assessment. PODs are developed 
based on a careful analysis of the doses in each toxicological study to 
determine the dose at which no adverse effects are observed (the NOAEL) 
and the lowest dose at which adverse effects of concern are identified 
(the LOAEL). Uncertainty/safety factors are used in conjunction with 
the POD to calculate a safe exposure level--generally referred to as a 
population-adjusted dose (PAD) or a reference dose (RfD)--and a safe 
margin of exposure (MOE). For non-threshold risks, the Agency assumes 
that any amount of exposure will lead to some degree of risk. Thus, the 
Agency estimates risk in terms of the probability of an occurrence of 
the adverse effect expected in a lifetime. For more information on the 
general principles EPA uses in risk characterization and a complete 
description of the risk assessment process, see http://www.epa.gov/pesticides/factsheets/riskassess.htm.
    A summary of the toxicological endpoints for mefenpyr-diethyl used 
for human risk assessment is shown in Table 1 of this unit.

     Table 1--Summary of Toxicological Doses and Endpoints for Mefenpyr-Diethyl for Use in Human Health Risk
                                                   Assessment
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                                        Point of departure and
          Exposure/scenario               uncertainty/safety     RfD, PAD, LOC for risk  Study and toxicological
                                               factors                 assessment                effects
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Acute dietary (Females 13-50 years of  No hazard was identified in any toxicity study for this duration of
 age).                                  exposure.
                                      --------------------------------------------------------------------------
Acute dietary (General population      No hazard was identified in any toxicity study for this duration of
 including infants and children).       exposure.
                                      --------------------------------------------------------------------------
Chronic dietary (All populations)....  NOAEL = 51 mg/kg/day...  Chronic RfD = 0.51 mg/   chronic oral toxicity
                                       UFA = 10x..............   kg/day.                  study (dog).
                                       UFH = 10x..............  cPAD = 0.51 mg/kg/day..  LOAEL = 260 mg/kg/day,
                                       FQPA SF = 1x...........                            based on increased
                                                                                          liver weight in both
                                                                                          sexes, cholestasis,
                                                                                          and increased alkaline
                                                                                          phosphatase.
                                                                                         chronic toxicity/
                                                                                          carcinogenicity study
                                                                                          (rat).
                                                                                         LOAEL = 252 (males)/318
                                                                                          (females) mg/kg/day,
                                                                                          based on statistically
                                                                                          significant increases
                                                                                          in reticulocyte counts
                                                                                          in both sexes, and
                                                                                          decreased RBC,
                                                                                          hemoglobin, and
                                                                                          hematocrit values in
                                                                                          females. NOAEL = 48.5
                                                                                          (males)/60 (females)
                                                                                          mg/kg/day.
                                      --------------------------------------------------------------------------
Cancer (oral)........................  Classification: Not likely to be carcinogenic to humans.
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UFA = extrapolation from animal to human (interspecies). UFH = potential variation in sensitivity among members
  of the human population (intraspecies). UFL = use of a LOAEL to extrapolate a NOAEL. UFS = use of a short-term
  study for long-term risk assessment. UFDB = to account for the absence of data or other data deficiency. FQPA
  SF = Food Quality Protection Act Safety Factor. PAD = population adjusted dose (a = acute, c = chronic). RfD =
  reference dose. MOE = margin of exposure. LOC = level of concern.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to mefenpyr-diethyl, EPA considered exposure under the 
petitioned-for tolerances as well as all existing mefenpyr-diethyl 
tolerances in 40 CFR 180.509. EPA assessed dietary exposures from 
mefenpyr-diethyl in food as follows:
    i. Acute exposure. Quantitative acute dietary exposure and 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. No such effects were 
identified in the toxicological studies for mefenpyr-diethyl; 
therefore, a quantitative acute dietary exposure assessment is 
unnecessary.
    ii. Chronic exposure. In conducting the chronic dietary exposure 
assessment EPA used the food consumption data from the USDA 1994-1996 
and 1998 CSFII. As to residue levels in food, EPA conducted a highly 
conservative chronic dietary risk assessment for mefenpyr-diethyl using 
tolerance level residues and assuming 100% crop treated for all 
commodities.
    iii. Cancer. Based on the data summarized in Unit III.A., EPA 
classified mefenpyr-diethyl as ``not likely to be carcinogenic to 
humans.'' Therefore, an exposure assessment to evaluate cancer risk is 
unnecessary for this chemical.
    2. Dietary exposure from drinking water. The Agency used screening 
level water exposure models in the dietary exposure analysis and risk 
assessment for mefenpyr-diethyl in drinking water. These simulation 
models take into

[[Page 23901]]

account data on the physical, chemical, and fate/transport 
characteristics of mefenpyr-diethyl. Further information regarding EPA 
drinking water models used in pesticide exposure assessment can be 
found at http://www.epa.gov/oppefed1/models/water/index.htm.
    Based on the First Index Reservoir Screening Tool (FIRST) and 
Screening Concentration in Ground Water (SCI-GROW2) models, the 
estimated drinking water concentrations (EDWCs) of mefenpyr-diethyl for 
chronic exposures for non-cancer assessments are estimated to be 3 ppb 
for surface water and 4 ppb for ground water.
    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure model. For chronic dietary risk 
assessment, the water concentration of value 4 ppb was used to assess 
the contribution to drinking 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). Mefenpyr-diethyl is 
not registered for any specific use patterns 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.'' EPA has not found mefenpyr-
diethyl to share a common mechanism of toxicity with any other 
substances, and mefenpyr-diethyl does not appear to produce a toxic 
metabolite produced by other substances. For the purposes of this 
tolerance action, therefore, EPA has assumed that mefenpyr-diethyl does 
not have 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 EPA's Web site at http://www.epa.gov/pesticides/cumulative cumulative.

 D. Safety Factor for Infants and Children

    1. In general. Section 408(b)(2)(C) of FFDCA provides that EPA 
shall apply an additional tenfold (10X) 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 database on toxicity 
and exposure unless EPA determines based on reliable data that a 
different margin of safety will be safe for infants and children. This 
additional margin of safety is commonly referred to as the FQPA Safety 
Factor (SF). In applying this provision, EPA either retains the default 
value of 10X, or uses a different additional safety factor when 
reliable data available to EPA support the choice of a different 
factor.
    2. Prenatal and postnatal sensitivity. There is little concern for 
prenatal toxicity resulting from exposure to mefenpyr-diethyl. There is 
no evidence of increased susceptibility [qualitative and quantitative] 
following in utero exposure to mefenpyr-diethyl in either the rat or 
rabbit developmental toxicity study, and there is no evidence of 
increased susceptibility [qualitative or quantitative] following in 
utero and/or pre-/post-natal exposure in the 2-generation reproduction 
study in rats. Developmental toxicity was not observed in the rat at 
the limit dose (1000 mg/kg/day) in one of two available rat 
developmental studies. In the second study, the only effects observed 
were decreased body-weight gain and food efficiency during the first 
week of dosing and increased spleen weights in the maternal animal and 
a marginal decrease in fetal body weight/body-weight gain during 
lactation (postnatal study). Developmental toxicity (abortions) was 
observed in the rabbit at a dose level of 250 mg/kg/day. In the 
reproduction study, decreased body weight and body-weight gain 
(parental animal and offspring) and an increase in spleen weight and in 
the severity (not incidence) of splenic extramedullary hematopoiesis 
were observed in females. There is no evidence of neurotoxicity, and 
there are no residual concerns.
    3. Conclusion. EPA has determined that reliable data show the 
safety of infants and children would be adequately protected if the 
FQPA safety factor were reduced to 1X. That decision is based on the 
following findings:
    i. The toxicology database for mefenpyr-diethyl is largely 
complete, missing only acute and subchronic neurotoxicity studies and 
an immunotoxicity study. EPA has determined that an additional 
uncertainty factor is not needed to account for the lack of these 
studies for the following reasons:
     There is no evidence in the existing studies to suggest 
that mefenpyr-diethyl targets either the immune system or the nervous 
system. EPA considered the entire toxicity database (subchronic, 
chronic, carcinogenicity, developmental and reproductive studies) of 
mefenpyr-diethyl for evidence of potential immunotoxic and neurotoxic 
effects. EPA did note that enlarged spleens, more severe hematopoiesis 
and hemosiderin deposits, and increased spleen weights were observed in 
mice at doses greater than the limit dose. However, these were 
determined to be non-specific changes not indicative of immunotoxicity. 
Additionally, no evidence of neurotoxicity was found. Therefore, based 
on the above considerations, EPA does not believe that conducting acute 
and subchronic neurotoxicity or immunotoxicity studies will result in a 
NOAEL less than the NOAEL of 51 mg/kg/day already set for mefenpyr-
diethyl.
     Overall, the toxicity of mefenpyr-diethyl is low. The 
endpoints were assumed by EPA to be treatment-related, a conservative 
assumption intended to ensure the risk assessment is protective of 
potential effects.
    Based on these considerations, EPA does not expect the required 
studies to provide lower points of departure than those currently 
selected for risk assessment, and an additional uncertainty factor is 
not needed to account for the lack of these studies.
    ii. There is no evidence of neurotoxicity in the available 
toxicology database and no evidence of significant developmental 
toxicity in either the rat or rabbit developmental toxicity studies. 
Based on these considerations, there is no need for a developmental 
neurotoxicity study or additional UFs to account for neurotoxicity.
    iii. There is no evidence of increased susceptibility in in utero 
rats or rabbits in the prenatal developmental studies or in young rats 
in the 2-generation reproduction study.
    iv. There are no residual uncertainties identified in the exposure 
databases. The dietary food exposure assessments were performed based 
on 100% CT and tolerance-level residues. EPA made conservative 
(protective) assumptions in the ground and surface water modeling used 
to assess exposure to mefenpyr-diethyl in drinking water. These 
assessments will not underestimate the exposure and risks posed by 
mefenpyr-diethyl.

E. Aggregate Risks and Determination of Safety

    EPA determines whether acute and chronic dietary pesticide 
exposures are safe by comparing aggregate exposure estimates to the 
acute PAD (aPAD) and chronic PAD (cPAD). For linear cancer risks, EPA 
calculates the lifetime probability of acquiring cancer given the

[[Page 23902]]

estimated aggregate exposure. Short-, intermediate-, and chronic-term 
risks are evaluated by comparing the estimated aggregate food, water, 
and residential exposure to the appropriate PODs to ensure that an 
adequate MOE exists.
    1. Acute risk. An acute aggregate risk assessment takes into 
account acute exposure estimates from dietary consumption of food and 
drinking water. No adverse effect resulting from a single oral exposure 
was identified and no acute dietary endpoint was selected. Therefore, 
mefenpyr-diethyl is not expected to pose an acute risk.
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that chronic exposure to 
mefenpyr-diethyl from food and water will utilize less than 1% of the 
cPAD for infants, less than 1 year old, the population group receiving 
the greatest exposure. There are no residential uses for mefenpyr-
diethyl.
    3. Short-term risk. Short-term aggregate exposure takes into 
account short-term residential exposure plus chronic exposure to food 
and water (considered to be a background exposure level). Because 
mefenpyr-diethyl does not have residential uses that would result in 
residential exposure and chronic dietary exposure has already been 
assessed under the appropriately protective cPAD (which is at least as 
protective as the POD used to assess short-term risk), no further 
assessment of short-term risk is necessary, and EPA relies on the 
chronic dietary risk assessment for evaluating short-term risk for, 
mefenpyr-diethyl.
    4. Intermediate-term risk. Intermediate-term aggregate exposure 
takes into account intermediate-term residential exposure plus chronic 
exposure to food and water (considered to be a background exposure 
level). Because mefenpyr-diethyl does not have residential uses that 
would result in residential exposure and chronic dietary exposure has 
already been assessed under the appropriately protective cPAD (which is 
at least as protective as the POD used to assess short-term risk), no 
further assessment of intermediate-term risk is necessary, and EPA 
relies on the chronic dietary risk assessment for evaluating 
intermediate-term risk for, mefenpyr-diethyl.
    5. Aggregate cancer risk for U.S. population. Based on the lack of 
evidence of carcinogenicity in two adequate rodent carcinogenicity 
studies, mefenpyr-diethyl is not expected to pose a cancer risk to 
humans.
    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, or to infants and children from aggregate 
exposure to mefenpyr-diethyl residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology is available to enforce the 
tolerance expression. An enforcement method for plants entitled ``An 
Analytical Method for Determination of Residues of AE F107892 
(mefenpyr-diethyl) and its Metabolites in Wheat and Barley by Gas 
Chromatography using Mass Selective Detection'' is available. 
Radiovalidation and independent laboratory validation (ILV) data have 
been submitted for the plant method. The Agency determined that this 
method is suitable for food tolerance enforcement of mefenpyr-diethyl 
and the three metabolites AE F094270, AE F113225, and/or AE F109453.
    This 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

    In making its tolerance decisions, EPA seeks to harmonize U.S. 
tolerances with international standards whenever possible, consistent 
with U.S. food safety standards and agricultural practices. EPA 
considers the international maximum residue limits (MRLs) established 
by the Codex Alimentarius Commission (Codex), as required by FFDCA 
section 408(b)(4). The Codex Alimentarius is a joint U.N. Food and 
Agriculture Organization/World Health Organization food standards 
program, and it is recognized as an international food safety 
standards-setting organization in trade agreements to which the United 
States is a party. EPA may establish a tolerance that is different from 
a Codex MRL; however, FFDCA section 408(b)(4) requires that EPA explain 
the reasons for departing from the Codex level. The Codex has not 
established a MRL for mefenpyr-diethyl.

C. Revisions to Petitioned-for Tolerances

    EPA has revised the sorghum commodity terms and the tolerances 
levels for both sorghum and grass commodities. The sorghum commodity 
terms have been revised from ``sorghum, grain;'' ``sorghum, forage;'' 
and ``sorghum, stover'' to ``sorghum, grain, grain;'' ``sorghum, grain, 
forage;'' and ``sorghum, grain, stover'' respectively to agree with the 
accepted terminology in the Agency's Food and Feed Vocabulary. EPA has 
increased the proposed tolerance for all proposed commodities as 
follows: Grass, forage from 1.5 to 1.6 ppm; grass, hay from 0.05 to 0.2 
ppm; sorghum, grain, forage from 0.1 to 0.4 ppm; sorghum, grain, grain 
from 0.01 to 0.04 ppm; and sorghum, grain, stover from 0.05 to 0.2 ppm. 
The grass, forage tolerance was increased from 1.5 ppm to 1.6 ppm 
because total mefenpyr-diethyl resides were detected up to 1.59 ppm at 
the proposed pre-harvest interval of 0 days in crop field trials. Since 
there were no detectible residues of parent or metabolites in the crop 
field trials for grass (hay) or sorghum, grain (forage; grain; or 
stover), the tolerances are being set based on the sum of the lowest 
level of method validation (LLMV) of the parent (mefenpyr-diethyl) and 
the three metabolites. The LLMV is 0.05 ppm for grass, hay and sorghum, 
grain, stover; 0.10 ppm in sorghum, grain, forage; and 0.01ppm in 
sorghum, grain, grain.
    Finally, as noted in Unit II, the petitioner requested that the 
proposed tolerances be established for residues of mefenpyr-diethyl, 
including its metabolites and degradates, but that compliance with the 
tolerance levels be determined by measuring only the sum of mefenpyr-
diethyl and its dichlorophenyl-pyrazoline metabolites, calculated as 
the stoichiometric equivalent of mefenpyr-diethyl, in or on the 
commodities. EPA is revising the tolerance expression for existing 
tolerances in 40 CFR 180.509 to agree with the tolerance expression 
proposed in this petition. EPA has determined that it is reasonable to 
make this change final without prior proposal and opportunity for 
comment, because public comment is not necessary, in that the change 
has no substantive effect on the tolerance, but rather is merely 
intended to clarify the existing tolerance expression.

V. Conclusion

    Therefore, tolerances are established for residues of the safener, 
mefenpyr-diethyl, including its metabolites and degradates, in or on 
grass, forage at 1.6 ppm; grass, hay at 0.2 ppm; sorghum, grain, forage 
at 0.4 ppm; sorghum, grain, grain at 0.04 ppm; and sorghum, grain, 
stover at 0.2 ppm. Compliance with these tolerances is to be determined 
by measuring the sum of mefenpyr-diethyl, (1-(2,4-dichlorophenyl)-4,5-
dihydro-5-methyl-1H-pyrazole-3,5-dicarboxylic acid, diethyl ester) and 
its dichlorophenyl-pyrazoline metabolites, calculated as the 
stoichiometric

[[Page 23903]]

equivalent of mefenpyr-diethyl, in or on the commodity.

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances 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 final rule has been 
exempted from review under Executive Order 12866, this final 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) or Executive Order 13045, entitled 
Protection of Children From Environmental Health Risks and Safety Risks 
(62 FR 19885, April 23, 1997). 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., 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).
    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.
    This final rule directly regulates growers, food processors, food 
handlers, and food retailers, not States or Tribes, nor does this 
action alter the relationships or distribution of power and 
responsibilities established by Congress in the preemption provisions 
of section 408(n)(4) of FFDCA. As such, the Agency has determined that 
this action will not have a substantial direct effect on States or 
Tribal governments, on the relationship between the national government 
and the States or Tribal governments, or on the distribution of power 
and responsibilities among the various levels of government or between 
the Federal Government and Indian Tribes. Thus, the Agency has 
determined that Executive Order 13132, entitled Federalism (64 FR 
43255, August 10, 1999) and Executive Order 13175, entitled 
Consultation and Coordination With Indian Tribal Governments (65 FR 
67249, November 9, 2000) do not apply to this final rule. In addition, 
this final rule does not impose any enforceable duty or contain any 
unfunded mandate as described under Title II of the Unfunded Mandates 
Reform Act of 1995 (UMRA) (Pub. L. 104-4).
    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).

VII. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report 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: April 21, 2011.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.
    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 180.509 is amended by revising paragraph (a) and adding 
paragraph (d) to read as follows:

Sec.  180.509  Mefenpyr-diethyl; tolerances for residues.

    (a) General. Tolerances are established for residues of the 
safener, mefenpyr-diethyl, including its metabolites and degradates, 
when applied at a rate no greater than 0.053 pound safener per acre per 
growing season in or on the commodities in the table below. Compliance 
with the tolerance levels specified below is to be determined by 
measuring only the sum of mefenpyr-diethyl (1-(2,4-dichlorophenyl)-4,5-
dihydro-5-methyl-1H-pyrazole-3,5-dicarboxylic acid, diethyl ester) and 
its 2,4-dichlorophenyl-pyrazoline metabolites, calculated as the 
stoichiometric equivalent of mefenpyr-diethyl, in or on the commodity.

------------------------------------------------------------------------
                                                              Parts per
                         Commodity                             million
------------------------------------------------------------------------
Barley, grain..............................................         0.05
Barley, hay................................................         0.2
Barley, straw..............................................         0.5
Cattle, meat byproducts....................................         0.1
Goat, meat byproducts......................................         0.1
Grass, forage..............................................         1.6
Grass, hay.................................................         0.2
Hog, meat byproducts.......................................         0.1
Horse, meat byproducts.....................................         0.1
Sheep, meat byproducts.....................................         0.1
Sorghum, grain, forage.....................................         0.4
Sorghum, grain, grain......................................         0.04
Sorghum, grain, stover.....................................         0.2
Wheat, forage..............................................         0.2
Wheat, grain...............................................         0.05
Wheat, hay.................................................         0.2
Wheat, straw...............................................         0.5
------------------------------------------------------------------------

* * * * *
    (d) Indirect or inadvertent residues. Tolerances are established 
for the indirect or inadvertent residues of mefenpyr-diethyl, including 
its metabolites and degradates, when applied at a rate no greater than 
0.053 pound safener per acre per growing season in or on the 
commodities identified in the table below. Compliance with the 
tolerance levels specified below is to be determined by measuring only 
the sum of mefenpyr-diethyl (1-(2,4-dichlorophenyl)-4,5-dihydro-5-
methyl-1H-pyrazole-3,5-dicarboxylic acid, diethyl ester) and its 2,4-
dichlorophenyl-pyrazoline metabolites, calculated as the stoichiometric 
equivalent of mefenpyr-diethyl, in or on the commodity.

------------------------------------------------------------------------
                                                              Parts per
                         Commodity                             million
------------------------------------------------------------------------
Canola, seed...............................................         0.02
Soybean, forage............................................         0.1
Soybean, hay...............................................         0.1
Soybean, seed..............................................         0.02
------------------------------------------------------------------------

[FR Doc. 2011-10439 Filed 4-28-11; 8:45 am]
BILLING CODE 6560-50-P