Document ID: EPA-HQ-OPP-2010-0524-0022
Agency: epa
Document Type: Rule
Title: Pesticide Tolerances: Trinexapac-ethyl
Posted Date: 2012-03-02T05:00Z

[Federal Register Volume 77, Number 42 (Friday, March 2, 2012)]
[Rules and Regulations]
[Pages 12740-12746]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-4984]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2010-0524; FRL-9337-9]

Trinexapac-ethyl; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for residues of 
trinexapac-ethyl in or on multiple commodities which are identified and 
discussed later in this document. Syngenta Crop Protection, Inc. 
requested these tolerances under the Federal Food, Drug, and Cosmetic 
Act (FFDCA).

DATES: This regulation is effective March 2, 2012. Objections and 
requests for hearings must be received on or before May 1, 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-2010-0524. 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 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. To access the 
OCSPP test guidelines referenced in this document electronically, 
please go to http://www.epa.gov/ocspp and select ``Test Methods and 
Guidelines.''

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

[[Page 12741]]

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-2010-0524 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 May 1, 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-2010-0524, 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 August 4, 2010, (75 FR 46925) (FRL-8834-
9), EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 
U.S.C. 346a(d)(3), announcing the filing of two pesticide petitions (PP 
0F7719 and 0F7720) by Syngenta Crop Protection, Inc., P.O. Box 18300, 
Greensboro, NC 27419. Petition 0F7719 requested that 40 CFR part 180 be 
amended by establishing tolerances for residues of the plant growth 
regulator, trinexapac-ethyl and its primary metabolite CGA-179500, in 
or on grass, forage, grown for seed at 1.60 parts per million (ppm); 
grass, hay, grown for seed at 3.5 ppm; grass, seed screenings, grown 
for seed at 45.0 ppm; grass, straw, grown for seed at 12 ppm; cattle 
(fat, meat, meat byproducts) at 0.05 ppm; goat (fat, meat, meat 
byproducts) at 0.05 ppm; horse (fat, meat, meat byproducts) at 0.05 ppm 
and sheep (fat, meat, meat byproducts) at 0.05 ppm. Petition 0F7720 
requested that 40 CFR part 180 be amended by establishing tolerances 
for residues in or on barley, grain at 1.6 ppm; barley, hay at 0.7 ppm; 
barley, straw at 0.35 ppm; cattle, kidney at 0.05 ppm; hog, kidney at 
0.05 ppm; oat, forage at 1.0 ppm; oat, grain at 4.1 ppm; oat, hay at 
1.3 ppm; oat, straw at 0.7 ppm; sugarcane, cane at 0.8 ppm; wheat, 
forage at 1.0 ppm; wheat, grain at 4.1 ppm; wheat, hay at 1.3 ppm and 
wheat, straw at 0.7 ppm.
    That notice referenced a summary of the petitions prepared by 
Syngenta Crop Protection, Inc., the registrant, which is available in 
the docket, http://www.regulations.gov.
    Based upon review of the data supporting the petition, EPA has 
revised most of the proposed tolerance levels, added tolerances for hog 
fat and meat, and deleted the proposed tolerance for cattle kidney. The 
reasons for these changes are explained in Unit IV.D.

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 trinexapac-ethyl 
including exposure resulting from the tolerances established by this 
action. EPA's assessment of exposures and risks associated with 
trinexapac-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.
    The acute toxicity of trinexapac-ethyl is low via the oral, eye, 
dermal, or inhalation routes of exposure, and it is not a dermal 
sensitizer.
    In adult animals (rats, rabbits, mice, dogs), no systemic adverse 
effects are seen below the limit dose following subchronic or chronic 
oral exposure with the exception of dogs. The 90-day subchronic dog 
study showed decreased body weight gain and food consumption, diffuse 
thymic atrophy, and changes in the epithelial cells of the renal 
tubules at 516/582 milligrams/kilogram/day (mg/kg/day) (males/females). 
Following chronic exposure, dose-related neuropathology of the brain 
was seen at >=365/357 mg/kg/day in male and female dogs respectively. 
The lesions remained confined to the supporting cells in the central 
nervous system and did not progress to more advanced or more extensive 
damage of the nervous tissue. They were not associated with other 
neuropathological findings or overt neurological signs so their 
biological significance is unknown. Similar lesions were not observed 
in the rat or mouse following acute, subchronic or chronic dietary 
exposure, and there was no other evidence in any other species tested 
to indicate a neurotoxicity potential. Furthermore, the brain lesions 
observed in the chronic dog study were not observed in the sub-chronic 
dog study up to 890 mg/kg/day and are thus not likely to develop from a 
short-term exposure.
    Evidence of increased qualitative and quantitative susceptibility 
to offspring exists at or above the limit dose of the developmental and 
reproduction studies. Developmental toxicity was observed in the rat 
(increased incidence of asymmetrical sternebrae) and rabbit (decreased 
number of live fetuses/litter and increased post-implantation loss) at 
the highest dose tested, with no evidence of maternal toxicity observed 
in either species. In the rat reproduction study, reproductive toxicity 
was not observed, but decreased pup survival

[[Page 12742]]

and decreased pup body weight/body-weight gain during lactation were 
observed above the limit dose with only reduced body weight and food 
consumption observed in the parental animals (>1,200 mg/kg/day).
    Trinexapac-ethyl is classified as ``Not likely to be carcinogenic 
to humans.'' The combined chronic toxicity/carcinogenicity study in the 
rat did not demonstrate an increase in any tumor type that would be 
relevant to humans. In the mouse, there was no evidence of 
carcinogenicity. The mutagenicity database is also complete, with no 
evidence of mutagenicity.
    Specific information on the studies received and the nature of the 
adverse effects caused by trinexapac-ethyl as well as the no-observed-
adverse-effect-level and the lowest-observed-adverse-effect-level from 
the toxicity studies can be found at http://www.regulations.gov in the 
document, ``Trinexapac-ethyl: Human Health Risk Assessment for the 
Section 3 Registration Action on Cereal Grains, Sugarcane, and Grasses 
Grown for Seed'' p. 48 in docket ID number EPA-HQ-OPP-2010-0524.

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 (LOC) 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 (U/SF) 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 trinexapac-ethyl used 
for human risk assessment is shown in Table 1 of this unit.

     Table 1--Summary of Toxicological Doses and Endpoints for Trinexapac-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 (Females 13-49       NOAEL = 60 mg/kg/     Acute RfD = 0.6 mg/  Developmental rabbit study.
 years of age).                     day.                  kg/day.             LOAEL = 360 mg/kg/day, based on a
                                   UFA = 10x.            aPAD = 0.6 mg/kg/     decrease in mean number of
                                   UFH = 10x.             day.                 fetuses/litter and an increase in
                                   FQPA SF = 1x.                               post-implantation loss.
����������������������������������
Acute dietary (General population     No appropriate endpoint for the general population including infants and
 including infants and children).                                     children
����������������������������������
Chronic dietary (All populations)  NOAEL = 31.6 mg/kg/   Chronic RfD = 0.32   Chronic oral toxicity study--dog.
                                    day.                  mg/kg/day.          LOAEL = 357 mg/kg/day, based on
                                   UFA = 10x.            cPAD = 0.32 mg/kg/    elevated serum cholesterol values
                                   UFH = 10x.             day.                 in females, mucoid feces in
                                   FQPA SF = 1x.                               females and bloody feces in both
                                                                               sexes, and minimal, focal
                                                                               vacuolation of the dorsal medial
                                                                               hippocampus and/or lateral
                                                                               midbrain in both sexes.
����������������������������������
Incidental oral (short and             No appropriate endpoint for the incidental oral scenario for children
 intermediate-term).
����������������������������������
Dermal & Inhalation (short- and    Dermal (or oral)      Residential........  Developmental rabbit study.
 intermediate-term-adults only).    study NOAEL = 60 mg/ LOC for MOE = 100..  LOAEL = 360 mg/kg, based on a
                                    kg/day (dermal       Occupational.......   decrease in mean number of
                                    absorption rate =    LOC for MOE = 100..   fetuses/litter and an increase in
                                    77.5%.                                     post-implantation loss.
                                   UFA = 10x.
                                   UFH = 10x.
                                   FQPA SF = 1x.
����������������������������������
Cancer (Oral, dermal, inhalation)           Classification: ``Not likely to be Carcinogenic to Humans''
----------------------------------------------------------------------------------------------------------------
UFA = extrapolation from animal to human (interspecies). UFH = potential variation in sensitivity among members
  of the human population (intraspecies). 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. Mg/kg/day--milligrams per day.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to trinexapac-ethyl, EPA considered exposure under the 
petitioned-for tolerances. There are no tolerances currently 
established for trinexapac-ethyl. EPA assessed dietary exposures from 
trinexapac-ethyl 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

[[Page 12743]]

occurring as a result of a 1-day or single exposure. In estimating 
acute dietary exposure, EPA used food consumption information from the 
U.S. 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 that residues are present in all 
commodities at the tolerance level and that 100% of commodities with 
tolerances are treated with trinexapac-ethyl. Dietary Exposure 
Evaluation Model (DEEM\TM\) 7.81 default concentration factors were 
used to estimate residues of trinexapac-ethyl in processed commodities. 
The acute dietary exposure was only estimated for females 13 to 49 
years old based on an in utero effect (decrease in mean number of 
fetuses/litter and an increase in post-implantation loss) identified in 
the rabbit developmental study. An endpoint of concern was not 
identified for the general U.S. population; however, the acute dietary 
assessment is protective of women that may become pregnant.
    ii. Chronic exposure. In estimating chronic dietary exposure, EPA 
used food consumption information from the USDA 1994-1996 and 1998 
CSFII. As to residue levels in food, EPA assumed that residues are 
present in all commodities at the tolerance level and that 100% of 
commodities with tolerances are treated with trinexapac-ethyl. DEEM\TM\ 
7.81 default concentration factors were used to estimate residues of 
trinexapac-ethyl in processed commodities.
    iii. Cancer. Based on the data summarized in Unit III.A., EPA has 
concluded that trinexapac-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 trinexapac-ethyl in drinking water. These simulation 
models take into account data on the physical, chemical, and fate/
transport characteristics of trinexapac-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 Pesticide Root Zone Model/Exposure Analysis Modeling 
System (PRZM/EXAMS) and Screening Concentration in Ground Water (SCI-
GROW) models, the estimated drinking water concentrations (EDWCs) of 
trinexapac-ethyl for acute exposures are estimated to be 12.61 parts 
per billion (ppb) for surface water and 0.009 ppb for ground water. 
Chronic exposures for non-cancer assessments are estimated to be 1.56 
ppb for surface water and 0.009 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 of value of 12.61 ppb was used to 
assess the contribution to drinking water. For chronic dietary risk 
assessment, the water concentration of value 1.56 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).
    Trinexapac-ethyl is currently registered for the following uses 
that could result in residential exposures: Residential lawns, athletic 
fields, parks, and golf courses. 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 both dermal and inhalation are considered to be short-
term only, due to the infrequent use patterns associated with homeowner 
products.
    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. Trinexapac-ethyl can be used 
in many areas that can be frequented by the general population 
including residential areas (e.g., home lawns, recreational turf). As a 
result, individuals can be exposed by entering these areas if they have 
been previously treated. Therefore, short-term dermal post-application 
exposures and risks were also assessed for trinexapac-ethyl. There is 
the potential for incidental oral exposure; however, since there is no 
toxicological endpoint of concern for that route, a quantitative 
assessment was not conducted. Further information regarding EPA 
standard assumptions and generic inputs for residential exposures may 
be found at http://www.epa.gov/pesticides/trac/science/trac6a05.pdf.
    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 
trinexapac-ethyl to share a common mechanism of toxicity with any other 
substances, and trinexapac-ethyl does not appear to produce a toxic 
metabolite produced by other substances. For the purposes of this 
tolerance action, therefore, EPA has assumed that trinexapac-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 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. Evidence of increased 
susceptibility to offspring exists at or above the limit dose of the 
developmental and reproduction studies. Developmental toxicity was 
observed in the rat (increased incidence of asymmetrical sternebrae) 
and rabbit (decreased number of live fetuses/litter and increased post-
implantation loss) at the highest dose tested, with no evidence of 
maternal toxicity observed in either species. In the rat reproduction 
study, reproductive toxicity was not observed, but decreased pup 
survival and decreased pup body weight/body-weight gain during 
lactation were observed above the limit dose with only reduced body 
weight and food consumption observed in the parental animals (>1,200 
mg/kg/day).
    3. Conclusion. EPA has determined that reliable data show the 
safety of infants and children would be adequately protected if the 
FQPA SF

[[Page 12744]]

were reduced to 1x. That decision is based on the following findings:
    i. The toxicology database for trinexapac-ethyl is largely 
complete, with the exception of a subchronic neurotoxicity study, which 
is a new data requirement under 40 CFR part 158 for registration of a 
pesticide (food and non-food uses OPPTS 870.6200b). Though dose-related 
neuropathology of the brain was observed in the dog, EPA has concluded 
that there is no need for a developmental neurotoxicity (DNT) study or 
additional UFs to account for neurotoxicity for the following reasons:
     These effects in the dog study were observed only at high 
doses (>357 mg/kg/day) and with chronic exposure, and no associated 
neurological signs or other neuropathology were observed. Furthermore, 
the lesions remained confined to the supporting cells in the central 
nervous system (CNS) and did not progress to more advanced or more 
extensive damage of the nervous tissue. There are clear NOAELs/LOAELs 
for this effect; in which the NOAEL dose is 10-fold lower than the 
LOAEL dose at which neuropathology is observed, and is therefore 
sufficiently protective. Furthermore, similar lesions were not observed 
in the rat or mouse following subchronic or chronic dietary exposure, 
and there was no other evidence in any species tested to indicate a 
neurotoxicity potential.
     Results of the acute neurotoxicity study show no 
indications of neurotoxicy at the highest dose.
    Although subchronic inhalation data on trinexapac-ethyl are not 
available and an oral study was selected for inhalation risk 
assessment, the selected points of departure are considered adequately 
protective for all exposed populations. Therefore, an additional 10x 
database UF was not retained for lack of inhalation toxicity data and 
these data are not being required.
    ii. Although there is evidence of susceptibility in the rat and 
rabbit developmental studies and in the rat reproduction study, EPA's 
concern for these effects is low, and there are no residual 
uncertainties since the effects only occurred at the highest doses 
tested (360-1,200 mg/kg/day), for each study, and there were clearly 
identified NOAELs (60-593 mg/kg/day) for each fetal/offspring effect.
    iii. There are no residual uncertainties in the exposure database. 
Because the acute and chronic dietary exposure estimates were based on 
several conservative assumptions (100% of crops treated with residues 
present at tolerance levels, default processing factors and screening 
level drinking water estimates), EPA is confident that the dietary 
exposure assessments do not underestimate risk to the general U.S. 
population and various population subgroups. Similarly, EPA does not 
believe that the non-dietary residential exposures are underestimated 
because they are based on the conservative assumptions of EPA's Draft 
Standard Operating Procedures (SOPs) for Residential Exposure 
Assessments (December 1997), and updates contained in the Science 
Advisory Council Policy 12 (February 2001) as well as the uses 
specified in the proposed labels.

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. Acute aggregate risk takes into account exposure to 
residues in food and drinking water alone. Therefore, acute aggregate 
risk is equivalent to the acute dietary risk as discussed in Unit 
III.C.1.i. All risk estimates are below EPA's level of concern. The 
acute dietary exposure estimate for females 13 to 49 years old will 
only utilize 2% of the aPAD, which is well below the Agency's level of 
concern (100% of the aPAD).
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that chronic exposure to 
trinexapac-ethyl from food and water will utilize 6% of the cPAD for 
children 1 to 2 years old, the population group receiving the greatest 
exposure. Based on the residential use patterns for trinexapac-ethyl, 
chronic residential exposure to residues is not expected.
    3. Short- and intermediate-term risk. Since the short- and 
intermediate-term toxicological endpoints for trinexapac-ethyl are the 
same for each route of exposure, only short-term exposures were 
assessed. Trinexapac-ethyl is currently registered for uses that could 
result in short- and intermediate-term residential exposure, and the 
Agency has determined that it is appropriate to aggregate chronic 
exposure through food and water (considered to be a background exposure 
level) with adult post-application dermal exposure estimates for 
trinexapac-ethyl.
    Using the exposure assumptions described in this unit, EPA has 
concluded the combined food, water, and adult post-application dermal 
exposures result in aggregate MOEs of 761 for liquid products and 601 
for granular products. Because EPA's level of concern for trinexapac-
ethyl is a MOE of 100 or below, these MOEs are not of concern.
    4. Aggregate cancer risk for U.S. population. Based on the lack of 
evidence of carcinogenicity in two adequate rodent carcinogenicity 
studies, trinexapac-ethyl is not expected to pose a cancer risk to 
humans.
    5. 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 trinexapac-ethyl residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology (Method GRM020.01A, which utilizes 
high performance liquid chromatography with triple-quadrupole mass 
spectrometry (LC-MS/MS)) is available to enforce the tolerance 
expression.
    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 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.
    There are no established or proposed Codex, Canadian, or Mexican 
MRLs for trinexapac-ethyl in or on any food or feed crops.

[[Page 12745]]

C. Response to Comments

    An anonymous citizen objected to the presence of any pesticide 
residues on food. The Agency understands the commenter's concerns and 
recognizes that some individuals believe that pesticides should be 
banned completely. However, the existing legal framework provided by 
section 408 of FFDCA contemplates that tolerances greater than zero may 
be set when persons seeking such tolerances or exemptions have 
demonstrated that the pesticide meets the safety standard imposed by 
that statute. This citizen's comment appears to be directed at the 
underlying statute and not EPA's implementation of it; the citizen has 
made no contention that EPA has acted in violation of the statutory 
framework.

D. Revisions to Petitioned-For Tolerances

    Many of the proposed tolerances are different from the tolerances 
being set by EPA. EPA is setting different levels than were proposed 
based on EPA's analysis of the field trial data using the Organization 
for Economic Cooperation and Development tolerance calculation 
procedures. Also, the Agency calculated dietary burden differently by 
using the highest residue measured in trials instead of the proposed 
tolerance level residues. Table 2.2.3, ``Tolerance Summary for 
Trinexapac-ethyl'' summarizes these differences on page 8 of the 
document, ``Trinexapac-ethyl: Human Health Risk Assessment for the 
Section 3 Registration Action on Cereal Grains, Sugarcane, and Grasses 
Grown for Seed'' which is located in docket ID number EPA-HQ-OPP-2010-
0524.

 V. Conclusion

    Therefore, tolerances are established for residues of trinexapac-
ethyl, including its metabolites and degradates, as set forth in the 
regulatory text. Compliance with the tolerance levels is to be 
determined by measuring both trinexapac-ethyl, ethyl 4-
(cyclopropylhydroxymethylene)-3,5-dioxocyclohexanecarboxylate and the 
associated metabolite trinexpac, 4-(cyclopropylhydroxymethylene)-3,5-
dioxocyclohexanecarboxylic acid, calculated as the stoichiometric 
equivalent of trinexapac-ethyl.

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances under section 408(d) of 
FFDCA in response to petitions 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: February 16, 2012.
Steven Bradbury,
Director, 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 180.662 is added to subpart C to read as follows:

Sec.  180.662  Trinexapac-ethyl; tolerances for residues.

    (a) General. Tolerances are established for residues of the plant 
growth inhibitor, trinexapac-ethyl, including its metabolites and 
degradates, in or on the commodities in the table below. Compliance 
with the tolerance levels specified below is to be determined by 
measuring both trinexapac-ethyl, ethyl 4-(cyclopropylhydroxymethylene)-
3,5-dioxocyclohexanecarboxylate and the associated metabolite, 
trinexpac, 4-(cyclopropylhydroxymethylene)-3,5-
dioxocyclohexanecarboxylic acid, calculated as the stoichiometric 
equivalent of trinexapac-ethyl, in or on the commodity.

------------------------------------------------------------------------
                                                              Parts per
                         Commodity                             million
------------------------------------------------------------------------
Barley, grain.............................................          2.0
Barley, hay...............................................          0.8
Barley, straw.............................................          0.4
Cattle, fat...............................................          0.02
Cattle, meat..............................................          0.02
Cattle, meat byproducts...................................          0.04
Goat, fat.................................................          0.02

[[Page 12746]]

 
Goat, meat................................................          0.02
Goat, meat byproducts.....................................          0.04
Grass, forage.............................................          1.5
Grass, hay................................................          4.0
Grass, seed screenings....................................         40.0
Grass, straw..............................................         10.0
Hog, fat..................................................          0.02
Hog, kidney...............................................          0.03
Hog, meat.................................................          0.02
Horse, fat................................................          0.02
Horse, meat...............................................          0.02
Horse, meat byproducts....................................          0.04
Oat, forage...............................................          1.0
Oat, grain................................................          4.0
Oat, hay..................................................          1.5
Oat, straw................................................          0.9
Sheep, fat................................................          0.02
Sheep, meat...............................................          0.02
Sheep, meat byproducts....................................          0.04
Sugarcane, cane...........................................          0.8
Wheat, forage.............................................          1.5
Wheat, grain..............................................          4.0
Wheat, hay................................................          1.5
Wheat, middlings..........................................          6.5
Wheat, straw..............................................          0.9
------------------------------------------------------------------------

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

[FR Doc. 2012-4984 Filed 3-1-12; 8:45 am]
BILLING CODE 6560-50-P