Document ID: EPA-HQ-OPP-2011-0428-0007
Agency: epa
Document Type: Rule
Title: Pesticide Tolerances: Carfentrazone-ethyl
Posted Date: 2012-05-04T04:00Z

[Federal Register Volume 77, Number 87 (Friday, May 4, 2012)]
[Rules and Regulations]
[Pages 26456-26462]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-10688]

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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2011-0428; FRL-9346-5]

Carfentrazone-ethyl; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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

SUMMARY: This regulation establishes tolerances for residues of 
carfentrazone-ethyl in or on crop group 18, non-grass animal feed 
(forage, hay, and seed). FMC Corporation requested these tolerances 
under the Federal Food, Drug, and Cosmetic Act (FFDCA).

DATES: This regulation is effective May 4, 2012. Objections and 
requests for hearings must be received on or before July 3, 2012, 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-2011-0428. 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; email 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

[[Page 26457]]

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://ecfr.gpoaccess.gov/cgi/t/text/text-idx?&c=ecfr&tpl=/ecfrbrowse/Title40/40tab_02.tpl.

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-OPP-2011-0428 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 
July 3, 2012. 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-2011-0428, by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the online 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 July 6, 2011 (76 FR 39360) (FRL-8875-6), 
EPA issued a notice pursuant to FFDCA section 408(d)(3), 21 U.S.C. 
346a(d)(3), announcing the filing of a pesticide petition (PP 1F7839) 
by FMC Corporation, 1735 Market St., Philadelphia, PA 19103. The 
petition requested that 40 CFR 180.515 be amended by establishing 
tolerances for residues of the herbicide, carfentrazone-ethyl and its 
metabolite, carfentrazone-ethyl chloropropionic acid, in or on alfalfa, 
forage at 5 parts per million (ppm); alfalfa, hay at 18 ppm; alfalfa, 
seed at 10 ppm; clover, forage at 5 ppm; clover, hay at 18 ppm; and 
clover, seed at 10 ppm. That notice referenced a summary of the 
petition prepared by FMC Corporation, 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 
revised the proposed individual alfalfa and clover tolerances to crop 
group 18 tolerances. The reason for this change is explained in Unit 
IV.C.

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 FFDCA section 408(b)(2)(D), and the factors 
specified in FFDCA section 408(b)(2)(D), EPA has reviewed the available 
scientific data and other relevant information in support of this 
action. EPA has sufficient data to assess the hazards of and to make a 
determination on aggregate exposure for carfentrazone-ethyl including 
exposure resulting from the tolerances established by this action. 
EPA's assessment of exposures and risks associated with carfentrazone-
ethyl 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.
    Carfentrazone-ethyl was ranked low in acute oral toxicity in rats 
via the oral, dermal, and inhalation routes of exposure. It was 
minimally irritating to eyes, non-irritating to skin, and not a skin 
sensitizer.
    The proposed mode of action of carfentrazone-ethyl in target plants 
is through inhibition of the enzyme protoporphyrinogen oxidase (PPO) 
which is involved in chlorophyll biosynthesis. In mammals, PPO is also 
an important enzyme in heme biosynthesis and its inhibition can lead 
toxic effects where heme is utilized (e.g., red blood cells). Some of 
the toxicities reported for carfentrazone-ethyl are consistent with 
this mode of action. The target tissues/organs identified are the blood 
and liver and the most sensitive species was the rat. Subchronic 
toxicity studies in rats, mice, and dogs demonstrated that the primary 
effects were on hematological parameters (decreased mean corpuscular 
hemoglobin (MCH) and mean corpuscular volume (MCV)). There was also 
increased urinary porphyrin excretion, increased liver weights, and 
liver histopathology findings consisting of hepatic pigment deposition, 
hepatocytomegaly, single cell necrosis, and cell mitosis. Similarly, 
chronic toxicity studies in rats and dogs demonstrated increased 
urinary porphyrin excretion and liver histopathology findings in rats 
and mice consisting of liver pigmentation and increases in red 
fluorescence. Fluorescence microscopy on liver sections also revealed 
red fluorescent granules consistent with porphyrin deposits in rats and 
mice.

[[Page 26458]]

    There was no evidence of increased susceptibility in prenatal 
developmental toxicity studies (rats and rabbits) or the 
multigenerational reproductive toxicity study in rats. Carfentrazone-
ethyl induced a significant increase in litter incidences of wavy and 
thickened ribs in rats at a dose (1,250 mg/kg/day) much higher than the 
dose (600 mg/kg/day) that caused maternal toxicity consistent with 
interference with porphyrin metabolism (i.e., staining of the 
abdominogenital area and of the cage pan liner). The rabbit prenatal 
developmental toxicity study did not yield any evidence of treatment-
related prenatal developmental toxicity even at the highest dose tested 
(HDT) (300 mg/kg/day). The offspring effects from the 2-generation 
reproduction study consisted of decreased pup body weight in both sexes 
of the F2 generation at the HDT (343 mg/kg/day) and at which 
maternal toxicity was observed in the form of decreased body-weight 
gains, increased liver weights, liver and bile duct histopathology, and 
reductions in the mean cell volume (F0 and F1 
males, F1 females), mean cell hemoglobin (F0 and 
F1 males, F1 females), hematocrit (F1 
males), and hemoglobin (F1 males).
    There is no concern for neurotoxicity. The results of the acute 
neurotoxicity study indicate clinical signs (i.e., salivation) and mild 
decreases in motor activity only on the treatment day and the 
subchronic neurotoxicity showed no signs of neurotoxicity up to the 
limit dose (1,178 mg/kg/day for males and 1,434 mg/kg/day for females).
    In a 21-day dermal toxicity study, carfentrazone-ethyl did not 
induce any type of dermal or systemic toxicity up to the limit dose of 
1,000 mg/kg/day. There are no toxicity studies based on repeated 
inhalation exposures to carfentrazone-ethyl. A waiver of a 28-day 
inhalation toxicity study was previously accepted based on its 
relatively low volatility, low acute inhalation lethality, and the 
large inhalation MOEs associated with the requested applications.
    The mutagenic test battery demonstrated that carfentrazone-ethyl is 
not mutagenic. In accordance with the Draft Proposed Guidelines for 
Carcinogen Risk Assessment (April, 1999), carfentrazone-ethyl is 
classified as a ``not likely human carcinogen,'' based on the lack of 
evidence for carcinogenicity in the mouse and rat.
    Specific information on the studies received and the nature of the 
adverse effects caused by carfentrazone-ethyl 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: ``Carfentrazone-ethyl. Section 3 
Registration for Application to the Non-grass Animal Feed Crop Group 
18. Human-Health Risk Assessment'' pp. 30-32 in docket ID number EPA-
HQ-OPP-2011-0428.

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 carfentrazone-ethyl 
used for human risk assessment is shown in the Table of this unit.

    Table--Summary of Toxicological Doses and Endpoints for Carfentrazone-ethyl for Use in Human Health Risk
                                                   Assessment
----------------------------------------------------------------------------------------------------------------
                                    Point of departure
        Exposure/scenario            and  uncertainty/    RfD, PAD, LOC for     Study and toxicological effects
                                      safety factors       risk assessment
----------------------------------------------------------------------------------------------------------------
Acute dietary (General population  NOAEL = 500 mg/kg/    Acute RfD = 5 mg/kg/ Acute neurotoxicity--rat.
 including infants and children).   day.                  day.                LOAEL = 1000 mg/kg/day based on
                                   UFA = 10x...........  aPAD = 5 mg/kg/day.   clinical observations
                                   UFH = 10x...........                        (salivation) and decreased motor
                                   FQPA SF = 1x........                        activity.
----------------------------------------------------------------------------------------------------------------
Chronic dietary (All populations)  NOAEL = 3 mg/kg/day.  Chronic RfD = 0.03   Chronic toxicity--rat.
                                   UFA = 10x...........   mg/kg/day.          LOAEL = 12 mg/kg/day based on
                                   UFH = 10x...........  cPAD = 0.03 mg/kg/    liver histopath-ology (increases
                                   FQPA SF = 1x........   day.                 in microscopic red fluor-escence
                                                                               and pigmentation) and increased
                                                                               urinary porphyrin levels in both
                                                                               sexes.
----------------------------------------------------------------------------------------------------------------
Incidental oral short-term (1 to   NOAEL = 50 mg/kg/day  LOC for MOE <=100..  Subchronic toxicity--dog.
 30 days) and intermediate term    UFA = 10x...........                       LOAEL = 150 mg/kg/day based on
 (1 to 6 months).                  UFH = 10x...........                        decreased body weight gain and
                                   FQPA SF = 1x........                        increased urinary excretion of
                                                                               porphyrins.
----------------------------------------------------------------------------------------------------------------
Dermal short-term (1 to 30 days)   Dermal risk assessment is not required--No toxicity seen at the limit-dose
 and intermediate-term (1 to 6      (1,000 mg/kg/day) in a 21-day rat dermal toxicity study and low level of
 months).                           concern for developmental effects.
----------------------------------------------------------------------------------------------------------------

[[Page 26459]]

 
Inhalation short-term (1 to 30     Oral NOAEL = 50 mg/   LOC for MOE <=100..  Subchronic toxicity--dog.
 days) and intermediate term (1     kg/day.                                   LOAEL = 150 mg/kg/day based on
 to 6 months).                     UFA = 10x...........                        decreased body weight gain and
                                   UFH = 10x...........                        increased urinary excretion of
                                   FQPA SF = 1x........                        porphyrins.
----------------------------------------------------------------------------------------------------------------
Cancer (Oral, dermal, inhalation)  Classification: ``not likely to be carcinogen;'' therefore, a quantitative
                                    cancer risk assessment is not necessary.
----------------------------------------------------------------------------------------------------------------
FQPA SF = Food Quality Protection Act Safety Factor. LOAEL = lowest-observed-adverse-effect-level. LOC = level
  of concern. mg/kg/day = milligram/kilogram/day. MOE = margin of exposure. NOAEL = no-observed-adverse-effect-
  level. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. UF = uncertainty factor.
  UFA = extrapolation from animal to human (interspecies). UFH = potential variation in sensitivity among
  members of the human population (intraspecies).

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to carfentrazone-ethyl, EPA considered exposure under the 
petitioned-for tolerances as well as all existing carfentrazone-ethyl 
tolerances in 40 CFR 180.515. EPA assessed dietary exposures from 
carfentrazone-ethyl in food as follows:
    i. Acute and chronic 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. Since such 
effects were identified for carfentrazone-ethyl, both acute and chronic 
dietary risk assessments were conducted. In estimating acute and 
chronic dietary exposure, EPA used food consumption information from 
the United States Department of Agriculture (USDA) 1994-1996 and 1998 
Nationwide Continuing Surveys of Food Intake by Individuals (CSFII). As 
to residue levels in food, EPA assumed tolerance-level residues or, if 
necessary, tolerance-level residues adjusted to account for the 
residues of concern for risk assessment, 100 PCT.
    ii. Cancer. Based on the data summarized in Unit III.A., EPA has 
concluded that carfentrazone-ethyl does not pose a cancer risk to 
humans. Therefore, a dietary exposure assessment for the purpose of 
assessing cancer risk was not conducted.
    2. Dietary exposure from drinking water. The Agency used screening 
level water exposure models in the dietary exposure analysis and risk 
assessment for carfentrazone-ethyl in drinking water. These simulation 
models take into account data on the physical, chemical, and fate/
transport characteristics of carfentrazone-ethyl. 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 Tier 1 Rice Model and Screening Concentration in 
Ground Water (SCI-GROW) models, the estimated drinking water 
concentrations (EDWCs) of carfentrazone-ethyl for acute exposures are 
estimated to be 126 parts per billion (ppb) for surface water and 13 
ppb for ground water. Chronic exposures for non-cancer assessments are 
estimated to be 48 ppb for surface water and 13 ppb for ground water.
    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure model. For acute dietary risk 
assessment, the water concentration value of 126 ppb was used to assess 
the contribution to drinking water. For chronic dietary risk 
assessment, the water concentration of value 48 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). Carfentrazone-ethyl 
is currently registered for the following uses that could result in 
residential exposures: Golf courses, residential lawns, and aquatic 
areas. EPA assessed residential exposure with the assumption that 
homeowner handlers wear shorts, short-sleeved shirts, socks, and shoes, 
and that they complete all tasks associated with the use of a pesticide 
product including mixing/loading, if needed, as well as the 
application. Residential handler exposure scenarios for residential 
lawn applications are considered to be short-term only, due to the 
infrequent use patterns associated with homeowner products. Therefore, 
short-term inhalation risk was assessed for residential handlers; 
however, since no hazard was identified via the dermal route of 
exposure, a dermal risk assessment was not conducted for residential 
handlers.
    EPA uses the term ``post-application'' to describe exposure to 
individuals that occur as a result of being in an environment that has 
been previously treated with a pesticide. Carfentrazone-ethyl can be 
used in many areas that can be frequented by the general population 
including home lawns, golf courses and aquatic recreational areas such 
as ponds and lakes that have been treated for removal of aquatic 
vegetation. As a result, individuals can be exposed by entering these 
areas if they have been previously treated. Therefore, short-term post-
application exposure and risk were also assessed for carfentrazone-
ethyl. The most conservative exposure scenario for adults, the aquatic 
exposure scenario (combined incidental oral and inhalation), was used 
to estimate post-application risk. For children, the most conservative 
exposure scenario, the hand-to-mouth exposure in residential turf 
scenario (incidental oral), was used to estimate post-application risk. 
Further information regarding EPA standard assumptions and generic 
inputs for residential exposures may be found at http://www.epa.gov/pesticides/science/residential-exposure-sop.html.
    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 
carfentrazone-ethyl to share a common mechanism of toxicity with any 
other substances, and carfentrazone-ethyl does not appear to produce a 
toxic metabolite produced by other

[[Page 26460]]

substances. For the purposes of this tolerance action, therefore, EPA 
has assumed that carfentrazone-ethyl 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.

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. As discussed in Unit III.A., 
based on the results of the rat/rabbit prenatal developmental toxicity 
studies and the rat 2-generation reproductive toxicity study, there is 
no evidence of increased pre- and/or postnatal sensitivity.
    3. Conclusion. EPA has determined that reliable data show the 
safety of infants and children would be adequately protected if the 
FQPA SF were reduced to 1x. That decision is based on the following 
findings:
    i. Although an immunotoxicity study is currently lacking in the 
toxicity database for carfentrazone-ethyl, there is no evidence in the 
current database that the immune system organs are directly affected 
following carfentrazone-ethyl exposure.
    ii. There is no indication that carfentrazone-ethyl is a neurotoxic 
chemical and there is no need for a developmental neurotoxicity study 
or additional UFs to account for neurotoxicity.
    iii. There is no evidence that carfentrazone-ethyl results in 
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 PCT and tolerance-level residues. EPA made conservative 
(protective) assumptions in the ground and surface water modeling used 
to assess exposure to carfentrazone-ethyl in drinking water. EPA used 
similarly conservative assumptions to assess post-application exposure 
of children as well as incidental oral exposure of toddlers. These 
assessments will not underestimate the exposure and risks posed by 
carfentrazone-ethyl.

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 
aPAD and cPAD. For linear cancer risks, EPA calculates the lifetime 
probability of acquiring cancer given the 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. Using the exposure assumptions discussed in this 
unit for acute exposure, the acute dietary exposure from food and water 
to carfentrazone-ethyl will occupy 1% of the aPAD for all infants (<1 
year old), the population group receiving the greatest exposure.
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that chronic exposure to 
carfentrazone-ethyl from food and water will utilize 69% of the cPAD 
for children 1-2 years old, the population group receiving the greatest 
exposure. Based on the explanation in Unit III.C.3., regarding 
residential use patterns, chronic residential exposure to residues of 
carfentrazone-ethyl is not expected.
    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). 
Carfentrazone-ethyl is currently registered for uses that could result 
in short-term residential exposure, and the Agency has determined that 
it is appropriate to aggregate chronic exposure through food and water 
with short-term residential exposures to carfentrazone-ethyl. Using the 
exposure assumptions described in this unit for short-term exposures, 
EPA has concluded that children (1-2 years old) provide the most 
conservative short-term exposure scenario. Chronic dietary estimates 
(food + water) for this age group, combined with incidental oral 
exposure from turf use (hand-to-mouth) results in aggregate MOEs of 
2,300. Because EPA's level of concern for carfentrazone-ethyl is a MOE 
of 100 or below, these MOEs are not of concern.
    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). Although intermediate-term residential exposures are not 
anticipated, the relevant short-/intermediate-term PODs are the same 
and, therefore, the short-term risk assessment is protective of 
intermediate-term exposure.
    5. Aggregate cancer risk for U.S. population. Based on the lack of 
evidence of carcinogenicity in two adequate rodent carcinogenicity 
studies, carfentrazone-ethyl 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 carfentrazone-ethyl residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology is available to enforce the 
tolerance expression. This analytical enforcement method involves 
separate analyses for parent and the metabolite. The parent is analyzed 
by evaporation and reconstitution of the sample prior to analysis by 
LC/MS/MS GC/ECD. The metabolite is refluxed in the presence of acid and 
cleaned up with solid phase extraction prior to analysis by LC/MS/MS.
    The method may be requested from: Chief, Analytical Chemistry 
Branch, Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD 
20755-5350; telephone number: (410) 305-2905; email 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 United Nations 
Food and Agriculture Organization/World Health Organization food 
standards program, and it is recognized as an international

[[Page 26461]]

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.
    There are no Codex, Canadian, or Mexican MRLs established for 
carfentrazone-ethyl in or on the requested crops.

C. Revisions to Petitioned-For Tolerances

    Based on the proposed uses and the submitted data, the Agency 
concludes that crop group 18 tolerances are appropriate for 
carfentrazone-ethyl, as opposed to individual tolerances on alfalfa and 
clover as proposed. These crop group tolerances are based on the 
submitted field trial data, which were conducted on the representative 
commodities for crop group 18, and the Organization for Economic Co-
operation and Development (OECD) tolerance calculation procedure.

V. Conclusion

    Therefore, tolerances are established for residues of 
carfentrazone-ethyl, including its metabolites and degradates, as set 
forth in the regulatory text. Compliance with the tolerance levels is 
to be determined by measuring only the sum of carfentrazone-ethyl 
(ethyl-alpha-2-dichloro-5-[-4-(difluoromethyl)-4,5-dihydro-3-methyl-5-
oxo-1H-1,2,4-triazol-1-yl]-4-fluorobenzenepropanoate) and its 
metabolite carfentrazone-chloropropionic acid (alpha, 2-dichloro-5-[-4-
difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]-4-
fluorobenzenepropanoic acid), calculated as the stoichiometric 
equivalent of carfentrazone-ethyl.

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances under FFDCA section 408(d) 
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 FFDCA section 408(d), 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 FFDCA section 408(n)(4). 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 25, 2012.
Daniel J. Rosenblatt,
Acting 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 180.515 is amended in paragraph (a) by revising the 
introductory text and by alphabetically adding the following entries to 
the table to read as follows:

Sec.  180.515  Carfentrazone-ethyl; tolerances for residues.

    (a) General. Tolerances are established for residues of the 
herbicide carfentrazone-ethyl, including its metabolites and 
degradates, in or on the commodities listed in the following table. 
Compliance with the following tolerance levels is to be determined by 
measuring only the sum of carfentrazone-ethyl (ethyl-alpha-2-dichloro-
5-[-4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H -1,2,4-triazol-1-
yl]-4-fluorobenzenepropanoate) and its metabolite carfentrazone-
chloropropionic acid (alpha, 2-dichloro-5-[-4-difluoromethyl)-4,5-
dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]-4-fluorobenzenepropanoic 
acid), calculated as the stoichiometric equivalent of carfentrazone-
ethyl, in or on the following commodities:

[[Page 26462]]

------------------------------------------------------------------------
                                                               Parts per
                          Commodity                             million
------------------------------------------------------------------------
 
                                * * * * *
Animal feed, nongrass, crop group 18, forage................         2.0
Animal feed, nongrass, crop group 18, hay...................         5.0
Animal feed, nongrass, crop group 18, seed..................        15.0
 
                                * * * * *
------------------------------------------------------------------------

* * * * *
[FR Doc. 2012-10688 Filed 5-3-12; 8:45 am]
BILLING CODE 6560-50-P