
[Federal Register Volume 76, Number 169 (Wednesday, August 31, 2011)]
[Rules and Regulations]
[Pages 54127-54133]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-22138]



[[Page 54127]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[ EPA-HQ-OPP-2011-0120; FRL-8885-4]


Tebuconazole; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for residues of 
tebuconazole in or on wheat, grain; oats, grain; wheat, shorts; and 
wheat, germ. Bayer CropScience requested these tolerances under the 
Federal Food, Drug, and Cosmetic Act (FFDCA).

DATES: This regulation is effective August 31, 2011. Objections and 
requests for hearings must be received on or before October 31, 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-2011-0120. 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: Tracy Keigwin, Registration Division 
(7505P), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 305-6605; e-mail address: keigwin.tracy@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.

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-2011-0120 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 
October 31, 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-2011-0120, 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 March 29, 2011 (76 FR 17374) (FRL-8867-
4), 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 0F7792 
by Bayer CropScience, 2 T.W. Alexander Drive, P.O. Box 12014, Research 
Triangle Park, NC 27709. The petition requested that 40 CFR 180.474 be 
amended by revising tolerances for residues of the fungicide 
tebuconazole in or on wheat, grain; and oats, grain to 0.15 ppm in 
order to harmonize with MRLs established in Canada by PMRA. That notice 
referenced a summary of the petition prepared by Bayer CropScience, 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 
determined that tolerances on the following processed forms of wheat 
and oats are needed also: Wheat, shorts and wheat, germ, each at 0.20 
ppm. Additionally, the Agency is establishing tolerances for 
tebuconazole of 0.20 ppm in shorts and germ of wheat. The reasons these 
additional tolerances are needed 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

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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 tebuconazole including 
exposure resulting from the tolerances established by this action. 
EPA's assessment of exposures and risks associated with tebuconazole 
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.
    Tebuconazole has low acute toxicity by the oral or dermal route of 
exposure, and moderate toxicity by the inhalation route. It is not a 
dermal sensitizer or a dermal irritant; however, it is slightly to 
mildly irritating to the eye. With repeated dosing, the primary target 
organs of tebuconazole toxicity are the liver, the adrenals, the 
hematopoetic system and the nervous system. Effects on these target 
organs were seen in both rodent and non-rodent species. In addition, 
ocular lesions were seen in dogs (including lenticular degeneration and 
increased cataract formation) following subchronic or chronic exposure. 
Oral administration of tebuconazole caused developmental toxicity in 
all species evaluated (rat, rabbit and mouse), with the most prominent 
effects in the nervous system. The developmental toxicity studies, 
including the developmental neurotoxicity study, demonstrated an 
increase in susceptibility in developing fetuses both quantitatively 
and qualitatively.
    Tebuconazole was classified as a Group C possible human carcinogen 
based on an increase in the incidence of hepatocellular adenomas, 
carcinomas, and combined adenomas/carcinomas in male and female mice. 
Mutagenicity data did not demonstrate any evidence of mutagenic 
potential for tebuconazole.
    Specific information on the studies received and the nature of the 
adverse effects caused by tebuconazole 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 entitled ``Tebuconazole: Human Health 
Risk Assessment to harmonize Tolerances of Tebuconazole in/on Oats and 
Wheat with Canada,'' pp. 32-37 in docket ID number EPA-HQ-OPP-2011-
0120.

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 tebuconazole used for 
human risk assessment is shown in the Table of this unit.

  Table--Summary of Toxicological Doses and Endpoints for Tebuconazole 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 (General population    LOAEL = 8.8 mg/kg/day.  Acute RfD = 0.029 mg/   Developmental Neurotoxicity
 including infants and children)     UF = 300..............   kg/day.                 Study--Rat. LOAEL = 8.8 mg/
 (Females 13-50 years of age).       UFA = 10x.............  aPAD = 0.029 mg/kg/day   kg/day based on decreases
                                     UFH = 10x.............                           in body weights, absolute
                                     FQPA (UFL) = 3x.......                           brain weights, brain
                                                                                      measurements and motor
                                                                                      activity in offspring.
Chronic dietary (All populations)..  LOAEL = 8.8 mg/kg/day.  Chronic RfD = 0.029 mg/ Developmental Neurotoxicity
                                     UF = 300..............   kg/day.                 Study--Rat.
                                     UFA = 10x.............  cPAD = 0.029 mg/kg/day  LOAEL = 8.8 mg/kg/day based
                                     UFH = 10x.............                           on decreases in body
                                     FQPA (UFL) = 3x.......                           weights, absolute brain
                                                                                      weights, brain
                                                                                      measurements and motor
                                                                                      activity in offspring.
Incidental oral short-term/          LOAEL = 8.8 mg/kg/day.  Residential LOC for     Developmental Neurotoxicity
 Intermediate term (1 to 30 days/1   UF = 300..............   MOE = 300.              Study--Rat. LOAEL = 8.8 mg/
 to 6 months).                       UFA = 10x.............                           kg/day based on decreases
                                     UFH = 10x.............                           in body weights, absolute
                                     FQPA (UFL) = 3x.......                           brain weights, brain
                                                                                      measurements and motor
                                                                                      activity in offspring.

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Dermal short-term/Intermediate term  LOAEL = 8.8 mg/kg/day.  Residential LOC for     Developmental Neurotoxicity
 (1 to 30 days/1 to 6 months).       UF = 300..............   MOE = 300.              Study--Rat.
                                     UFA = 10x.............                          LOAEL = 8.8 mg/kg/day based
                                     UFH = 10x.............                           on decreases in body
                                     UFL = 3x..............                           weights, absolute brain
                                     DAF = 23.1%...........                           weights, brain
                                                                                      measurements and motor
                                                                                      activity in offspring.
Inhalation short-term/Intermediate   LOAEL = 8.8 mg/kg/day.  Residential LOC for     Developmental Neurotoxicity
 term (1 to 30 days/1 to 6 months).  UF = 300..............   MOE = 300.              Study--Rat.
                                     UFA = 10x.............                          LOAEL = 8.8 mg/kg/day based
                                     UFH = 10x.............                           on decreases in body
                                     UFL = 3x..............                           weights, absolute brain
                                     Inhalation and oral                              weights, brain
                                      absorption are                                  measurements and motor
                                      assumed to be                                   activity in offspring.
                                      equivalent..
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Cancer (Oral, dermal, inhalation)..  Classification: Group C--possible human carcinogen based on statistically
                                      significant increase in the incidence of hepatocellular adenoma,
                                      carcinoma, and combined adenoma/carcinomas in both sexes of NMRI mice.
                                      Considering that there was no evidence of carcinogenicity in rats, there
                                      was no evidence of genotoxicity for tebuconazole, and tumors were only
                                      seen at a high and excessively toxic dose in mice, EPA concluded that the
                                      chronic RfD would be protective of any potential carcinogenic effect. The
                                      chronic RfD value is 0.029 mg/kg/day which is approximately 9,600 fold
                                      lower than the dose that would induce liver tumors (279 mg/kg/day).
----------------------------------------------------------------------------------------------------------------
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. DAF = dermal absorption factor.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to tebuconazole, EPA considered exposure under the petitioned-
for tolerances as well as all existing tebuconazole tolerances in 40 
CFR 180.474. EPA assessed dietary exposures from tebuconazole 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.
    In estimating acute 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, anticipated residues 
for bananas, grapes, raisins, nectarines, peaches, and peanut butter 
were derived using the 2002-2006 USDA Pesticide Data Program (PDP) 
monitoring data. Anticipated residues for all other registered food 
commodities were based on field trial data. For uses associated with PP 
0F7792, 100 percent crop treated (PCT) was assumed. DEEM (ver. 7.81) 
default processing factors were assumed for processed commodities 
associated with petition 0F7792. For several other uses EPA used PCT 
data as specified in Unit III.C.1.iv.
    ii. Chronic exposure. In conducting the chronic dietary exposure 
assessment, EPA used the same data sources as stated in Unit III. C. 1. 
i. for acute exposure.
    iii. Cancer. As explained in Unit III.B., the chronic risk 
assessment is considered to be protective of any cancer effects; 
therefore, a separate quantitative cancer dietary risk assessment was 
not conducted.
    iv. Anticipated residue and PCT information. Section 408(b)(2)(E) 
of FFDCA authorizes EPA to use available data and information on the 
anticipated residue levels of pesticide residues in food and the actual 
levels of pesticide residues that have been measured in food. If EPA 
relies on such information, EPA must require pursuant to FFDCA section 
408(f)(1) that data be provided 5 years after the tolerance is 
established, modified, or left in effect, demonstrating that the levels 
in food are not above the levels anticipated. For the present action, 
EPA will issue such data call-ins as are required by FFDCA section 
408(b)(2)(E) and authorized under FFDCA section 408(f)(1). Data will be 
required to be submitted no later than 5 years from the date of 
issuance of these tolerances.
    Section 408(b)(2)(F) of FFDCA states that the Agency may use data 
on the actual percent of food treated for assessing chronic dietary 
risk only if:
     Condition a: The data used are reliable and provide a 
valid basis to show what percentage of the food derived from such crop 
is likely to contain the pesticide residue.
     Condition b: The exposure estimate does not underestimate 
exposure for any significant subpopulation group.
     Condition c: Data are available on pesticide use and food 
consumption in a particular area, the exposure estimate does not 
understate exposure for the population in such area.
    In addition, the Agency must provide for periodic evaluation of any 
estimates used. To provide for the periodic evaluation of the estimate 
of PCT as required by FFDCA section 408(b)(2)(F), EPA may require 
registrants to submit data on PCT.
    The Agency estimated the PCT for existing uses as follows:
    Grapes: 25% acute assessment, 15% chronic assessment; grape, 
raisin: 25% acute assessment, 15% chronic assessment; nectarine: 25% 
acute assessment, 20% chronic assessment; peach: 20% acute assessment, 
15% chronic assessment; and peanuts: 45% acute assessment, 15% chronic 
assessment.
    In most cases, EPA uses available data from United States 
Department of Agriculture/National Agricultural Statistics Service 
(USDA/NASS), proprietary market surveys, and the National Pesticide Use 
Database for the chemical/crop combination for the most

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recent 6-7 years. EPA uses an average PCT for chronic dietary risk 
analysis. The average PCT figure for each existing use is derived by 
combining available public and private market survey data for that use, 
averaging across all observations, and rounding to the nearest 5%, 
except for those situations in which the average PCT is less than one. 
In those cases, 1% is used as the average PCT and 2.5% is used as the 
maximum PCT. EPA uses a maximum PCT for acute dietary risk analysis. 
The maximum PCT figure is the highest observed maximum value reported 
within the recent 6 years of available public and private market survey 
data for the existing use and rounded up to the nearest multiple of 5%.
    The Agency also used PCT information for tebuconazole on the 
following recently approved uses: Apples, apricots, cherries 
(preharvest), sweetcorn, hops, plums, and turnips. The PCT for each 
crop is as follows: Apples, acute assessment 44%, chronic assessment 
41%; Apricots, acute assessment 56%, chronic assessment 43%; Cherries, 
preharvest, acute assessment 42%, chronic assessment 37%; Corn, sweet, 
acute assessment 22%, chronic assessment 14%; Hops, acute assessment 
64%, chronic assessment 64%; Plum, acute assessment 26%, chronic 
assessment 24%; Turnip, acute assessment 68%, chronic assessment 44%. 
EPA estimates PCT for a new pesticide use by assuming that its actual 
PCT during the initial five years of use on a specific use site will 
not exceed the recent PCT of the market leader (i.e. ,the one with the 
greatest PCT) on that site. An average market leader PCT, based on 
three recent surveys of pesticide usage, if available, is used for 
chronic risk assessment, while the maximum PCT from the same three 
recent surveys, if available, is used for acute risk assessment. The 
average and maximum market leader PCTs may each be based on one or two 
surveys if three are not available. Comparisons are only made among 
pesticides of the same pesticide type (i.e., the leading fungicide on 
the use site is selected for comparison with the new fungicide). The 
market leader PCTs used to determine the average and the maximum may be 
each for the same pesticide or for different pesticides since the same 
or different pesticides may dominate for each year. Typically, EPA uses 
USDA/NASS as the source for raw PCT data because it is publicly 
available. When a specific use site is not surveyed by USDA/NASS, EPA 
uses other sources including proprietary data.
    An estimated PCT, based on the average PCT of the market leaders, 
is appropriate for use in chronic dietary risk assessment, and an 
estimated projected percent crop treated (PPCT), based on the maximum 
PCT of the market leaders, is appropriate for use in acute dietary risk 
assessment. This method of estimating PCTs for a new use of a 
registered pesticide or a new pesticide produces high-end estimates 
that are unlikely, in most cases, to be exceeded during the initial 
five years of actual use. Predominant factors that bear on whether the 
PCTs could be exceeded may include PCTs of similar chemistries, pests 
controlled by alternatives, pest prevalence in the market and other 
factors. Based on these factors, EPA has adjusted upward the estimates 
for three crops: Cherries post-harvest, hops and turnip greens.
    The Agency believes that the three conditions discussed in Unit 
III.C.1.iv. have been met. With respect to Condition a, PCT estimates 
are derived from Federal and private market survey data, which are 
reliable and have a valid basis. The Agency is reasonably certain that 
the percentage of the food treated is not likely to be an 
underestimation. As to Conditions b and c, regional consumption 
information and consumption information for significant subpopulations 
is taken into account through EPA's computer-based model for evaluating 
the exposure of significant subpopulations including several regional 
groups. Use of this consumption information in EPA's risk assessment 
process ensures that EPA's exposure estimate does not understate 
exposure for any significant subpopulation group and allows the Agency 
to be reasonably certain that no regional population is exposed to 
residue levels higher than those estimated by the Agency. Other than 
the data available through national food consumption surveys, EPA does 
not have available reliable information on the regional consumption of 
food to which tebuconazole may be applied in a particular area.
    2. Dietary exposure from drinking water. The Agency used screening 
level water exposure models in the dietary exposure analysis and risk 
assessment for tebuconazole in drinking water. These simulation models 
take into account data on the physical, chemical, and fate/transport 
characteristics of tebuconazole. 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.
    Surface water estimated drinking water concentrations (EDWCs) 
resulting from the Pesticide Root Zone Model/Exposure Analysis Modeling 
System (PRZM/EXAMS) were used in the dietary assessment, since they 
were higher than the EDWCs resulting from the Screening Concentration 
in Ground Water (SCI GROW). A distribution of 30-year daily surface 
water concentrations was estimated for the EDWCs of tebuconazole for 
acute exposures. The EDWC for chronic, noncancer exposure is estimated 
to be 59.0 [mu]g/L for surface 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).
    Tebuconazole has currently registered uses that could result in 
residential exposures. Short-term dermal and inhalation exposures are 
possible for residential adult handlers mixing, loading, and applying 
tebuconazole products outdoors to ornamental plants. Short- and 
intermediate-term dermal postapplication exposures are also possible to 
golfers from treated golf turf and to adults and children from contact 
to treated wood structures. Children may also be exposed via the 
incidental oral route when playing on treated wood structures. Long-
term exposure is not expected. As a result, risk assessments have been 
completed for residential handler scenarios as well as residential 
post-application scenarios.
    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.''
    Tebuconazole is a member of the triazoles (and more specifically, 
triazole-derivative fungicides). Although triazoles act similarly in 
plants (fungi) by inhibiting ergosterol biosynthesis, there is not 
necessarily a relationship between their pesticidal activity and their 
mechanism of toxicity in mammals. Structural similarities do not 
constitute a common mechanism of toxicity. Evidence is needed to 
establish that the chemicals operate by the same, or essentially the 
same, sequence of major biochemical events. In triazole-

[[Page 54131]]

derivative fungicides, however, a variable pattern of toxicological 
responses is found: Some are hepatotoxic and hepatocarcinogenic in 
mice; some induce thyroid tumors in rats; and some induce 
developmental, reproductive, and neurological effects in rodents. 
Furthermore, the triazoles produce a diverse range of biochemical 
events including altered cholesterol levels, stress responses, and 
altered DNA methylation. It is not clearly understood whether these 
biochemical events are directly connected to their toxicological 
outcomes. Thus, there is currently no evidence to indicate that 
triazole-derivative fungicides share common mechanisms of toxicity and 
EPA is not following a cumulative risk approach based on a common 
mechanism of toxicity for the triazole-derivative fungicides. For 
information regarding EPA's procedures for cumulating effects from 
substances found to have a common mechanism of toxicity, see EPA's Web 
site at http://www.epa.gov/pesticides/cumulative.
    However, the triazole-derivative fungicides can form the common 
metabolites 1,2,4-triazole and conjugated triazole metabolites. To 
support existing tolerances and to establish new tolerances for 
triazole-derivative fungicides, including tebuconazole, EPA conducted a 
human health risk assessment for exposure to 1,2,4-triazole, 
triazolylalanine, and triazolylacetic acid resulting from the use of 
all current and pending uses of any triazole-derivative fungicide. The 
risk assessment is a highly conservative, screening-level evaluation in 
terms of hazards associated with common metabolites (e.g., use of a 
maximum combination of uncertainty factors) and potential dietary and 
non-dietary exposures (i.e., high end estimates of both dietary and 
non-dietary exposures). In addition, the Agency retained the additional 
10X FQPA safety factor for the protection of infants and children. The 
assessment includes evaluations of risks for various subgroups, 
including those comprised of infants and children. The Agency's 
complete risk assessment is found at http://www.regulations.gov, docket 
ID number EPA-HQ-OPP-2011-0120 in the document entitled ``Common 
Triazole Metabolites: Updated Dietary (Food + Water) Exposure and Risk 
Assessment to Address the Amended Metconazole Section 3 Registration to 
Add Uses on Tuberous and Corm Vegetables (Group 1C) and Bushberry 
Subgroup 13-07B''. This document updates another EPA risk assessment on 
triazole-derived pesticides which can be found in the reregistration 
docket for propiconazole at http://www.regulations.gov, docket ID 
number EPA-HQ-OPP-2005-0497.

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. The toxicity database for 
tebuconazole includes prenatal developmental toxicity studies in three 
species (mouse, rat, and rabbit), a reproductive toxicity study in 
rats, acute and subchronic neurotoxicity studies in rats, and a 
developmental neurotoxicity study in rats. The data from prenatal 
developmental toxicity studies in mice and a developmental 
neurotoxicity study in rats indicated an increased quantitative and 
qualitative susceptibility following in utero exposure to tebuconazole. 
The NOAELs/LOAELs for developmental toxicity in these studies were 
found at dose levels less than those that induce maternal toxicity or 
in the presence of slight maternal toxicity. There was no indication of 
increased quantitative susceptibility in the rat and rabbit 
developmental toxicity studies, the NOAELs for developmental toxicity 
were comparable to or higher than the NOAELs for maternal toxicity. In 
all three species, however, there was indication of increased 
qualitative susceptibility. For most studies, minimal maternal toxicity 
was seen at the LOAEL (consisting of increases in hematological 
findings in mice, increased liver weights in rabbits and rats, and 
decreased body weight gain/food consumption in rats) and did not 
increase substantially in severity at higher doses; however, there was 
more concern for the developmental effects at each LOAEL which included 
increases in runts, increased fetal loss, and malformations in mice, 
increased skeletal variations in rats, and increased fetal loss and 
frank malformations in rabbits. Additionally, more severe developmental 
effects (including frank malformations) were seen at higher doses in 
mice, rats and rabbits. In the developmental neurotoxicity study, 
maternal toxicity was seen only at the high dose (decreased body 
weights, body weight gains, and food consumption, prolonged gestation 
with mortality, and increased number of dead fetuses), while offspring 
toxicity (including decreases in body weight, brain weight, brain 
measurements and functional activities) was seen at all doses.
    Available data indicated greater sensitivity of the developing 
organism to exposure to tebuconazole, as demonstrated by increases in 
qualitative sensitivity in prenatal developmental toxicity studies in 
rats, mice, and rabbits, and by increases in both qualitative and 
quantitative sensitivity in the developmental neurotoxicity study in 
rats with tebuconazole. However, the degree of concern is low because 
the toxic endpoints in the prenatal developmental toxicity studies were 
well characterized with clear NOAELs established and the most sensitive 
endpoint, which is found in the developmental neurotoxicity study, has 
been used for overall risk assessments. Therefore, there are no 
residual uncertainties for pre- and/or postnatal susceptibility.
    3. Conclusion. The Agency has determined that reliable data show 
the safety of infants and children would be adequately protected if the 
FQPA SF were reduced to 3x for all potential exposure scenarios. The 
decision is based on the following findings:
    i. The toxicity database for tebuconazole is complete with the 
exception of an immunotoxicity study requirement under the new 40 CFR 
part 158 guidelines for toxicity data. The available guideline studies 
do not suggest that tebuconazole directly targets the immune system. A 
peer-reviewed developmental neurotoxicity/immunotoxicity literature 
study found in high dose groups (60 mg/kg/day) increased spleen weights 
and alterations in splenic lymphocyte subpopulations. At the same dose 
there were no effects seen in the T-cell dependent antibody response to 
sheep red blood cells (SRBC) and natural killer (NK) cell activity 
indicating that tebuconazole did not alter the functional immune 
response in rats. Based on guideline and open literature, the overall 
weight of evidence suggests that tebuconazole does not directly target 
the immune system. The Agency does not believe that conducting a 
functional immunotoxicity study will result in a lower POD than 
currently used for overall risk assessment; therefore, a

[[Page 54132]]

database uncertainty factor (UFDB) is not needed to account for the 
lack of the study.
    ii. Although there is qualitative evidence of increased 
susceptibility in the prenatal developmental studies in rats, the 
Agency did not identify any residual uncertainties after establishing 
toxicity endpoints and traditional UFs to be used in the risk 
assessment of tebuconazole. The degree of concern for residual 
uncertainties for prenatal and/or postnatal toxicity is low.
    iii. A 3x FQPA safety factor is needed to address the failure to 
achieve a NOAEL in the developmental neurotoxicity (DNT) study. 
Reduction of the FQPA safety factor from 10x to 3x is based on a 
Benchmark Dose (BMD) analysis of the datasets relevant to the adverse 
offspring effects (decreased body weight, decreases in absolute brain 
weights, changes in brain morphometric parameters, and decreases in 
motor activity) seen at the LOAEL in the DNT study. The BMD analysis 
models or estimates the dose (BMD) associated with a specified measure 
or change (e.g. a dose representing a 10% change) of a biological 
effect over the control. All of the BMDLs (the lower limit of a one-
sided 95% confidence interval on the BMD) modeled successfully on 
statistically significant effects are 1-2x lower than the LOAEL. The 
results indicate that the use of the FQPA safety factor of 3x would not 
underestimate risk. Using a 3x FQPA safety factor in the risk 
assessment (8.8 mg/kg/day / 3x = 2.9 mg/kg/day) is further supported by 
the NOAELs established in other studies in the tebuconazole toxicity 
database [i.e., 3 and 2.9 mg/kg/day, from a DNT study in mice and a 
chronic toxicity study in dogs, respectively (respective LOAELs 10 and 
4.5 mg/kg/day)].
    iv. There are no residual uncertainties identified in the exposure 
databases. Although the acute and chronic food exposure assessments are 
refined, EPA believes that the assessments are based on reliable data 
and will not underestimate exposure/risk. The drinking water estimates 
were derived from conservative screening models. The residential 
exposure assessment utilizes reasonable high-end variables set out in 
EPA's Occupational/Residential Exposure SOPs (Standard Operating 
Procedures). The aggregate assessment is based upon reasonable worst-
case residential assumptions, and is also not likely to underestimate 
exposure/risk to any subpopulation, including those comprised of 
infants and children.

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 
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 tebuconazole will occupy 33% of the aPAD for the U.S. population and 
62% of the aPAD for the population group (children 3-5 years old) 
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 
tebuconazole from food and water will utilize 8.8% of the cPAD for the 
U.S. population and 16% of the cPAD for the most highly exposed 
population group (all infants (< 1 year old).
    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). Tebuconazole 
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 tebuconazole.
    Using the exposure assumptions described in this unit for short 
term exposures, EPA has concluded that the short-term aggregate MOE 
from dietary exposure (food + drinking water) and non-occupational/
residential handler exposure for adults using a hose-end sprayer on 
ornamentals is 370. The short-term aggregate MOE from dietary exposure 
and exposure from golfing is 1,900. The likelihood of a residential 
handler treating ornamentals with tebuconazole and then playing golf on 
a tebuconazole-treated course is considered low; therefore, each 
scenario is considered separately with background dietary exposure. The 
short-term aggregate MOE to children from dietary exposure and exposure 
from wood surfaces treated at the above ground use rate is 470. The 
short-term aggregate MOE to children from dietary exposure and exposure 
to wood surfaces treated at the below ground use rate is 220. The 
combined and aggregate MOEs for wood treated for below ground uses are 
lower than the target MOE (300) and thus indicate a potential risk of 
concern. However, the combined MOE for wood treated for above-ground 
uses is not lower than the target MOE, and therefore is not of concern. 
Exposure to above-ground wood is expected to more closely represent 
actual exposures to children. Frequency of exposures to above-ground 
wood should greatly exceed any exposures to below-ground wood, and 
exposures to below ground wood would be minimal, or negligible. It is 
unrealistic to expect a full duration of exposure to below ground wood. 
Therefore, EPA concludes that there is not a concern for short-term 
aggregate risk.
    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). Tebuconazole is currently registered for uses that could result 
in intermediate-term residential exposure, and the Agency has 
determined that it is appropriate to aggregate chronic exposure through 
food and water with intermediate-term residential exposures to 
tebuconazole. Since the POD, relevant exposure scenarios and exposure 
assumptions used for intermediate-term aggregate risk assessments are 
the same as those used for short-term aggregate risk assessments, the 
short-term aggregate risk assessments represent and are protective of 
both short and intermediate-term exposure durations.
    5. Aggregate cancer risk for U.S. population. As discussed in this 
unit, the chronic risk assessment is considered to be protective of any 
cancer effects; therefore, because the chronic risk assessment 
indicates exposure is lower than the cPAD, tebuconazole does not pose a 
cancer risk of concern.
    6. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to the general population, or to infants and children from aggregate 
exposure to tebuconazole residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate gas chromatography/nitrogen phosphorous detector (GC/NPD) 
and liquid chromatography/mass

[[Page 54133]]

spectrometry/mass spectrometry (LC/MS/MS) methods are available for 
both collecting and enforcing tolerances for tebuconazole and its 
metabolites in plant commodities, livestock matrices and processing 
studies. The methods have been adequately validated by an independent 
laboratory in conjunction with a previous petition. The method may be 
requested from: Chief, Analytical Chemistry Branch, Environmental 
Science Center, 701 Mapes Rd., Ft. Meade, MD 20755-5350; telephone 
number: (410) 305-2905; e-mail address: residuemethods@epa.gov.

B. International Residue Limits

    Codex and Canada have established maximum residue limits (MRLs) for 
tebuconazole in/on a variety of plant and livestock commodities. The 
tolerance expression for tebuconazole is harmonized between U.S., 
Codex, and Canada. The proposed tolerances will harmonize established 
U.S. tolerances on oat and wheat with current Canadian MRLs.
    There are currently no Codex MRLs for wheat and oats.

C. Revisions to Petitioned-For Tolerances

    The Agency concluded that residues of tebuconazole do not 
concentrate in wheat bran, flour or middlings, but do concentrate in 
shorts and germ (2.5X). As a result, a tolerance in/on wheat, shorts 
and wheat, germ, each at 0.20 ppm (highest average field trial (HAFT) 
value = 0.08 ppm), is required.

V. Conclusion

    Therefore, tolerances are established for residues of tebuconazole, 
in or on wheat, grain, and oat, grain at 0.15 ppm and wheat, shorts, 
and wheat, germ at 0.20 ppm.

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: August 17, 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 180.474, paragraph (a)(1) is amended by:
0
i. Revising the introductory text;
0
ii. Revising the entries for ``oat, grain'' and ``wheat, grain'' in the 
table; and
0
iii. Alphabetically adding entries for ``wheat, shorts'' and ``wheat, 
germ'' to the table.
    The amendments read as follows:


Sec.  180.474  Tebuconazole; tolerances for residues.

    (a) * * *
    (1) Tolerances are established for residues of tebuconazole, alpha-
[2-(4-chlorophenyl)ethyl]-alpha-(1,1-dimethylethyl)-1H-1,2,4-triazole-
1-ethanol, 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 only tebuconazole 
[[alpha]-[2-(4-chlorophenyl) ethyl]-[alpha]-(1,1-dimethylethyl)-1H-
1,2,4-triazole-1-ethanol], in or on the commodity.

------------------------------------------------------------------------
                                                                 Parts
                          Commodity                               per
                                                                million
------------------------------------------------------------------------
 
                                * * * * *
Oat, grain...................................................       0.15
Wheat, grain.................................................       0.15
Wheat, shorts................................................       0.20
Wheat, germ..................................................       0.20
 
                                * * * * *
------------------------------------------------------------------------

* * * * *
[FR Doc. 2011-22138 Filed 8-30-11; 8:45 am]
BILLING CODE 6560-50-P


