Document ID: EPA-HQ-OPP-2008-0327-0003
Agency: epa
Document Type: Rule
Title: Pesticide Tolerances: Prothioconazole
Posted Date: 2009-04-01T04:00Z

[Federal Register: April 1, 2009 (Volume 74, Number 61)]
[Rules and Regulations]               
[Page 14744-14749]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr01ap09-15]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2008-0327; FRL- 8403-9]

 
Prothioconazole; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation increases a tolerance for combined residues of 
prothioconzole and prothioconazole-desthio, calculated as parent in or 
on, wheat, forage. Bayer CropScience requested this tolerance under the 
Federal Food, Drug, and Cosmetic Act (FFDCA).

DATES: This regulation is effective April 1, 2009. Objections and 
requests for hearings must be received on or before June 1, 2009 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-2008-0327. 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: Bryant Crowe, Registration Division 
(7505P), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 305-0025; e-mail address: crowe.bryant@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 Access Electronic Copies of this Document?

    In addition to accessing electronically available documents at 
http://www.regulations.gov, you may access this Federal Register 
document electronically through the EPA Internet under the ``Federal 
Register'' listings at http://www.epa.gov/fedrgstr. You may also access 
a frequently updated electronic version of EPA's tolerance regulations 
at 40 CFR part 180 through the Government Printing Office's e-CFR cite 
at http://www.gpoaccess.gov/ecfr.

C. Can I File an Objection or Hearing Request?

    Under section 408(g) of FFDCA, 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-2008-0327 in the subject line on the first 
page of your submission. All requests must be in writing, and must be 
mailed or delivered to the Hearing Clerk as required by 40 CFR part 178 
on or before June 1, 2009.
    In addition to filing an objection or hearing request with the 
Hearing Clerk as described in 40 CFR part 178, please

[[Page 14745]]

submit a copy of the filing that does not contain any CBI for inclusion 
in the public docket that is described in ADDRESSES. Information not 
marked confidential pursuant to 40 CFR part 2 may be disclosed publicly 
by EPA without prior notice. Submit this copy, identified by docket ID 
number EPA-HQ-OPP-2008-0327, 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. Petition for Tolerance

    In the Federal Register of June 4, 2008 (73 FR 31863) (FRL-8365-3), 
EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21 U.S.C. 
346a(d)(3), announcing the filing of a pesticide petition (PP 7F7279) 
by Bayer CropScience, P.O. Box 12014, 2 T.W. Alexander Dr., Research 
Triangle Park, NC 27709. The petition requested that 40 CFR 180.626 be 
amended by increasing a tolerance for combined residues of the 
fungicide prothioconazole, 2-[2-(1-chlorocyclopropyl)-3-(2-
chlorophenyl)-2-hydroxypropyl]-1,2-dihydro-3H-1,2,4-triazole-3-thione, 
and prothioconazole-desthio, in or on, wheat, forage from 6.0 to 8.0 
parts per million (ppm). That notice referenced a summary of the 
petition prepared by Bayer CropScience, the registrant, which is 
available to the public in the docket, http://www.regulations.gov. 
There were no comments received in response to the notice of filing.

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 the petitioned-for 
tolerances for combined residues of prothioconazole, and 
prothioconazole-desthio, calculated as parent, in or on wheat, forage 
at 8.0 ppm. EPA's assessment of exposures and risks associated with 
establishing tolerances 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. Prothioconazole has low acute toxicity by oral, dermal, and 
inhalation routes. It is not a dermal sensitizer, or a skin or eye 
irritant. Prothioconazole's metabolite, prothioconazole-desthio, also 
has low acute toxicity by oral, dermal, and inhalation routes. It is 
not a dermal sensitizer, or a skin irritant, but it is a slight eye 
irritant. The subchronic and chronic studies show that the target 
organs at the lowest-observed-adverse effect level (the LOAEL) include 
the liver, kidney, urinary bladder, thyroid and blood. In addition, the 
chronic studies showed body weight and food consumption changes, and 
toxicity to the lymphatic and GI systems. Prothioconazole and its 
metabolites may be primary developmental toxicants, producing effects 
including malformations in the conceptus at levels equal to or below 
maternally toxic levels in some studies; particularly those conducted 
using prothioconazole-desthio. Reproduction studies in the rat with 
prothioconazole and prothioconazole-desthio suggested that these 
chemicals may not be primary reproductive toxicants. Acute and 
subchronic neurotoxicity studies were conducted in the rat using 
prothioconazole. A developmental neurotoxicity study was conducted in 
the rat using prothioconazole-desthio. The available data show that the 
prothioconazole-desthio metabolite produces toxicity at the lowest dose 
levels in the areas of subchronic, developmental, reproductive, and 
neurotoxic toxicities compared with prothioconazole and the two 
additional metabolites that were tested. The available carcinogenicity 
and/or chronic studies in the mouse and rat, using both prothioconazole 
and prothioconazole-desthio, show no increase in tumor incidence. 
Therefore, EPA has concluded prothioconazole or its metabolites are not 
carcinogenic, and are classified ``Not likely to be Carcinogenic to 
Humans'' according to the 2005 Cancer Guidelines. Specific information 
on the studies received and the nature of the adverse effects caused by 
prothioconazole as well as the no-observed-adverse-effect-level (NOAEL) 
and LOAEL from the toxicity studies can be found at http://
www.regulations.gov in document Prothioconazole; Pesticide Tolerance 
pages 14714-14719 in docket ID number EPA-HQ-OPP-2007-0178.

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no 
appreciable risk, a toxicological point of departure (POD) is 
identified as the basis for derivation of reference values for risk 
assessment. The POD may be defined as the highest dose at which no 
adverse effects are observed (the NOAEL) in the toxicology study 
identified as appropriate for use in risk assessment. However, if a 
NOAEL cannot be determined, the LOAEL at which adverse effects of 
concern are identified (the LOAEL) or a Benchmark Dose (BMD) approach 
is sometimes used for risk assessment. Uncertainty/safety factors (UFs) 
are used in conjunction with the POD to take into account uncertainties 
inherent in the extrapolation from laboratory animal data to humans and 
in the variations in sensitivity among members of the human population 
as well as other unknowns. Safety is assessed for acute and chronic 
dietary risks by comparing aggregate food and water exposure to the 
pesticide to the acute population adjusted dose (aPAD) and chronic 
population adjusted dose (cPAD). The

[[Page 14746]]

aPAD and cPAD are calculated by dividing the POD by all applicable UFs. 
Aggregate short-term, intermediate-term, and chronic-term risks are 
evaluated by comparing food, water, and residential exposure to the POD 
to ensure that the margin of exposure (MOE) called for by the product 
of all applicable UFs is not exceeded. This latter value is referred to 
as the Level of Concern (LOC).
    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 
greater than that 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/
oppfead1/trac/science; http://www.epa.gov/pesticides/factsheets/
riskassess.htm; and http://www.epa.gov/pesticides/trac/science/
aggregate.pdf.
    A summary of the toxicological endpoints for prothioconazole used 
for human risk assessment can be found at http://www.regulations.gov in 
document Prothioconazole: Human Health Risk Assessment for Proposed 
Section 3 Seed treatment Use on Wheat, Barley, and Triticale, Plus 
Increase Tolerance on Forage of Wheat, Barley, and Triticale pages 20-
21 in docket ID number EPA-HQ-OPP-2008-0327.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to prothioconazole, EPA considered exposure under the 
petitioned-for tolerances as well as all existing prothioconazole 
tolerances in (40 CFR 180.626). EPA assessed dietary exposures from 
prothioconazole residues 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 U.S. Department of Agriculture (USDA) 1994-1996 
and 1998 Nationwide Continuing Surveys of Food Intake by Individuals 
(CSFII). A moderately refined acute dietary exposure (food and drinking 
water) assessment was conducted for prothioconazole. Average field 
trial values, empirical processing factors, and livestock maximum 
residues were incorporated into the refined acute assessment. The 
assessment also assumed 100 percent of crops covered by the existing 
tolerances, as well as the changed tolerance on wheat forage, are 
treated with prothioconazole.
    ii. Chronic exposure. In conducting the chronic dietary exposure 
assessment EPA used the food consumption data from the USDA 1994-1996 
and 1998 CSFII. A moderately refined chronic dietary exposure (food and 
drinking water) assessment was conducted for prothioconazole. Average 
field trial values, empirical processing factors, and livestock maximum 
residues were incorporated into the refined acute assessment. The 
assessment also assumed 100 percent of crops covered by the existing 
tolerances, as well as the changed tolerance on wheat forage, are 
treated with prothioconazole.
    iii. Cancer. The available toxicology studies in the mouse and rat 
showed no increase in tumor incidence, and therefore the Agency has 
concluded that neither prothioconazole, nor its metabolites are 
carcinogenic. Thus classified, by the Agency, as ``Not Likely to 
Carcinogenic to Humans'' according to the 2005 Cancer Guidelines. 
Consequently, a quantitative dietary cancer assessment was not 
performed.
    iv. Anticipated residue and percent crop treated (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 section 408(f)(1) of FFDCA 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 section 408(b)(2)(E), and authorized under section 
408(f)(1) of FFDCA. Data will be required to be submitted no later than 
5 years from the date of issuance of this tolerance. Average residues 
and 100 PCT were assumed for all food commodities.
    2. Dietary exposure from drinking water. The Agency used screening 
level water exposure models in the dietary exposure analysis and risk 
assessment for prothioconazole in drinking water. These simulation 
models take into account data on the physical, chemical, and fate/
transport characteristics of prothioconazole. 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 
prothioconazole for acute exposures are estimated to be 29 parts per 
billion (ppb) for surface water and 0.67 ppb for ground water. The 
EDWCs for chronic exposures are estimated to be 13 ppb for surface 
water and 0.67 ppb for ground water.
    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure models. For acute dietary risk 
assessment, the water concentration value of 29 ppb was used to assess 
the contribution from drinking water. For the chronic dietary risk 
assessment, the water concentration value of 13 ppb was used to assess 
the contribution from drinking water. EPA used the EDWCs from surface 
water only in assessing the risk from prothioconazole because the EDWCs 
for ground water source are less than 1 ppb, and considered minimal in 
comparison to 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).
    Prothioconazole is not registered for use patterns that would 
result in residential exposure.
    4. Cumulative effects from substances with a common mechanism of 
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when 
considering whether to establish, modify, or revoke a tolerance, the 
Agency consider ``available information'' concerning the cumulative 
effects of a particular pesticide's residues and ``other substances 
that have a common mechanism of toxicity.''
    Prothioconazole is a member of the triazole-containing class of 
pesticides, often referred to as the conazoles. EPA is not currently 
following a cumulative risk approach based on a common mechanism of 
toxicity for the conazoles. The conazole pesticides, as a whole, tend 
to exhibit carcinogenic, developmental, reproductive, and/or 
neurological effects in mammals. Additionally, all the members of this 
class of compounds are capable of forming, via environmental and 
metabolic activities, 1,2,4-triazole, triazolylalanine and/or 
triazolylacetic acid. These metabolites have also been shown to cause 
developmental, reproductive, and/or neurological effects. Structural 
similarities and sharing a common effect does not constitute a common 
mechanism of toxicity. Evidence is needed to establish

[[Page 14747]]

that the chemicals operate ``by the same, or essentially the same 
sequence of major biochemical events. Hence, the underlying basis of 
toxicity is the same, or essentially the same for each chemical.'' 
(EPA, 2002) A number of potential events could contribute to the 
toxicity of conazoles (e.g., altered cholesterol levels, stress 
responses, altered DNA methylation). At this time, there is not 
sufficient evidence to determine whether conazoles share common 
mechanisms of toxicity. Without such understanding, there is no basis 
to make a common mechanism of toxicity finding for the diverse range of 
effects found. Investigations into the conazoles are currently being 
undertaken by the EPA's Office of Research and Development. When the 
results of this research are available, the Agency will make a 
determination of whether there is a common mechanism of toxicity and, 
therefore, a basis for assessing cumulative risk. 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 website at http://www.epa.gov/pesticides/
cumulative.
     Triazole-derived pesticides can form the common metabolite 1,2,4-
triazole and three triazole conjugates (triazole alanine, triazole 
acetic acid, and triazolylpyruvic acid). To support existing tolerances 
and to establish new tolerances for triazole-derivative pesticides, 
including prothioconazole, EPA conducted a human health risk assessment 
for exposure to 1,2,4-triazole, triazole alanine, and triazole acetic 
acid resulting from the use of all current and pending uses of any 
triazole-derived fungicide as of September 1, 2005. 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 included evaluations of risks for various subgroups, 
including those comprised of infants and children. The Agency's 
September 1, 2005 risk assessment can be found in the propiconazole 
reregistration docket at http://www.regulations.gov (Docket ID EPA-HQ-
OPP-2005-0497). In October and December of 2008, EPA updated the 
dietary and aggregate risk assessments for exposure to 1,2,4-triazole, 
triazole alanine, triazole acetic acid, and triazolylpyruvic acid 
resulting from the use of all current and pending uses of any triazole-
derived fungicide to support existing tolerances and to establish new 
tolerances for new uses of metconazole (canola, corn, cotton, and 
sugarcane; PP 7F7221, 7F7292, and 08FL03), propiconazole (beets, 
parsley, and pineapple; PP 7F7300), prothioconazole (wheat and barley; 
PP 7F7279), and tetraconazole (grapes; PP 7E7273). These updated 
dietary and aggregate assessments are below the Agency's level of 
concern. These updated triazole risk assessments can be found in the 
Rule's docket (EPA-HQ-OPP-2008-0327) and the following associated 
dockets at http://www.regulations.gov (Docket IDs EPA-HQ-OPP-2007-514 
and EPA-HQ-OPP-2008-0718).

D. Safety Factor for Infants and Children

    1. In general. Section 408(b)(2)(c) of FFDCA provides that EPA 
shall apply an additional tenfold (10X) margin of safety for infants 
and children in the case of threshold effects to account for prenatal 
and postnatal toxicity and the completeness of the database on toxicity 
and exposure unless EPA determines based on reliable data that a 
different margin of safety will be safe for infants and children. This 
additional margin of safety is commonly referred to as the FQPA safety 
factor (SF). In applying this provision, EPA either retains the default 
value of 10X, or uses a different additional safety factor when 
reliable data available to EPA support the choice of a different 
factor.
    2. Prenatal and postnatal sensitivity. There is evidence of 
increased susceptibility following prematal/or postnatal exposure in:
    i. Rat developmental toxicity studies with prothioconazole as well 
as its prothioconazole-desthio and sulfonic acid K salt metabolites.
    ii. Rabbit developmental toxicity studies with prothioconazole-
desthio.
    iii. A rat developmental neurotoxicity study with prothioconazole-
desthio; and
    iv. Multi-generation reproduction studies in the rat with 
prothioconazole-desthio. Effects include skeletal structural 
abnormalities, such as cleft palate, deviated snout, malocclusion, 
extra ribs, and developmental delays. Available data also show that the 
skeletal effects such as extra ribs are not completely reversible after 
birth in the rat, but persist as development continues. Although 
increased susceptibility was seen in these studies, the Agency 
concluded that there is a low concern and no residual uncertainties for 
prenatal and/or postnatal toxicity effects of prothioconazole because:
     Developmental toxicity NOAELs and LOAELs from prenatal 
exposure are well characterized after oral and dermal exposure
     The off-spring toxicity NOAELs and LOAELs from postnatal 
exposures are well characterized; and
     The NOAEL for the fetal effect malformed vertebral body 
and ribs is used for assessing acute risk of females 13 years and older 
and, because it is lower than the NOAELs in other developmental 
studies, is protective of all potential developmental effects.
    3. Conclusion. EPA has determined that reliable data show the 
safety of infants and children would be adequately protected if the 
FQPA SF were reduced to 1X. That decision is based on the following 
findings:
     i. The toxicity database for prothioconazole is complete, except 
for immunotoxicity testing. EPA began requiring functional 
immunotoxicity testing of all food and non-food use pesticides on 
December 26, 2007. Although an immunotoxicity study in the mouse is 
part of the existing prothioconazole toxicity data base, this study as 
reported does not satisfy the current guideline requirements for an 
immunotoxicity study (OPPTS 870.7800). As such, EPA is requiring that 
an immunotoxicity study be submitted which meets guideline 
requirements. EPA has evaluated the available prothioconazole toxicity 
database (including the non-guideline study in the mouse) to determine 
whether an additional database uncertainty factor is needed to account 
for potential immunotoxicity. In one chronic study in the rat (but not 
in the mouse or dog), blood leukocyte counts were significantly 
elevated at the high dose level (750 milligrams/kilogram/day (mg/kg/
day)) along with increased thrombocyte counts and decrease hemoglobin. 
However, this finding is made in the presence of toxicity to a broad 
range of organ systems such as the liver, urinary bladder, kidney, 
thyroid, and decreased body weight gains. Furthermore, no signs of 
immunotoxicity, including evidence of toxicity to the lymphatic system, 
were observed at dose levels up to 400 mg/kg/day in the non-guideline 
immunotoxicity study in the mouse. There appears to be no basis for 
concern for immunotoxicity, particularly at the Points of Departure 
(POD) for prothioconazole and its metabolites which, at 2.0 and 1.1 mg/
kg/day (Acute and Chronic Reference Dose (aRfD and cRfD), respectively) 
are two orders of

[[Page 14748]]

magnitude lower than the 400 and 750 mg/kg/day dose levels mentioned in 
this Unit. This finding, along with the absence of immunotoxicity 
observed in the subchronic and chronic studies with prothioconazole and 
its metabolites supports the reduction of the FQPA factor to 1X in the 
interim, pending receipt of an acceptable guideline immunotoxicity 
study.
    ii. Previously, because of incomplete data reporting, there were 
uncertainties regarding dose levels at which neurotoxicities (brain 
morphometrics and peripheral nerve degeneration) were occurring in the 
pups. Because of this database uncertainty, the FQPA safety factor was 
retained at 10X in previous hazard characterizations. Critical data on 
brain morphometry and peripheral nerve lesions in a rat developmental 
neurotoxicity study have now been submitted and reviewed. Upon 
evaluation of these new data, neither the apparent increases in axonal 
degeneration at the high dose or the brain morphometric changes at the 
low and mid doses were considered treatment-related. Therefore, these 
data support the reduction of the FQPA factor to 1X.
    iii. Although increased susceptibility was seen in the 
developmental and reproduction studies, the Agency concluded that there 
is a low concern and no residual uncertainties for prenatal and/or 
postnatal toxicity effects of prothioconazole for the reasons explained 
in Unit III.D.2.
    iv. There are no residual uncertainties identified in the exposure 
databases. The dietary food exposure assessments were performed based 
on 100 PCT and tolerance-level or anticipated residues derived from 
reliable residue field trials. EPA made conservative (protective) 
assumptions in the ground water and surface water modeling used to 
assess exposure to prothioconazole in drinking water. Residential 
exposures are not expected. These assessments will not underestimate 
the exposure and risks posed by prothioconazole.

E. Aggregate Risks and Determination of Safety

    EPA determines whether acute and chronic pesticide exposures are 
safe by comparing aggregate exposure estimates to the Acute Percent 
Adjusted Dose and Chronic Percent Adjusted Dose (aPAD and cPAD). The 
aPAD and cPAD represent the highest safe exposures, taking into account 
all appropriate SFs. EPA calculates the aPAD and cPAD by dividing the 
POD by all applicable UFs. For linear cancer risks, EPA calculates the 
probability of additional cancer cases given the estimated aggregate 
exposure. Short-term, intermediate-term, and chronic-term risks are 
evaluated by comparing the estimated aggregate food, water, and 
residential exposure to the POD to ensure that the MOE called for by 
the product of all applicable UFs is not exceeded.
    1. Acute risk. An acute aggregate risk assessment takes into 
account exposure estimates from acute dietary consumption of food and 
drinking water. No adverse effect resulting from a single-oral exposure 
was identified and therefore no acute dietary endpoint was selected for 
the general population. However, an acute dietary endpoint was selected 
for the population subgroup females 13 to 49 years of age. Using the 
exposure assumptions discussed in this unit for acute exposure, the 
acute dietary exposure from food and drinking water to prothioconazole 
will occupy 8% of the aPAD for (female 13 to 49 years old).
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that chronic exposure to 
prothioconazole from food and water will utilize 22% of the cPAD for 
(infants less than 1 year old) the population group receiving the 
greatest exposure. There are no residential uses for prothioconazole.
    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).
    Prothioconazole is not registered for any use patterns that would 
result in residential exposure. Therefore, the short-term aggregate 
risk is the sum of the risk from exposure to prothioconazole through 
food and water and will not be greater than the chronic 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).
    Prothioconazole is not registered for any use patterns that would 
result in intermediate-term residential exposure. Therefore, the 
intermediate-term aggregate risk is the sum of the risk from exposure 
to prothioconazole through food and water, which has already been 
addressed, and will not be greater than the chronic aggregate risk.
    5. Aggregate cancer risk for U.S. population. Aggregate cancer risk 
for U.S. population. The available studies in the mouse and rat show no 
increase in tumor incidence, therefore the Agency has concluded that 
neither prothioconazole nor its metabolites are carcinogenic, and are 
classified ``Not likely to be Carcinogenic to Humans'' according to the 
2005 Cancer Guidelines. Therefore, prothioconazole is not expected to 
pose a cancer risk.
    6. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to the general population, or to infants and children from aggregate 
exposure to prothioconazole residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology are available to enforce the 
tolerance expression, consisting of liquid chromatography/tandem 
massspectrometry (LC/MS/MS) for both plant and livestock commodities, 
usingtandem mass spectrometry electrospray ionization in both the 
positive and negative modes. Both methods (LC/MS/MS Method RPA JA/03/01 
for plants and LC/MS/MS Method Bayer Report No. 200537 for animals) 
have successfully passed tolerance method validation at ACB/BEAD. 
Methods may be requested from: Chief, Analytical Chemistry Branch, 
Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD 20755-5350; 
telephone number: (410) 305-2905; e-mail address: 
residuemethods@epa.gov.

B. International Residue Limits

    There are no maximum residue limits (MRLs) (tolerances) established 
for prothioconazole in Codex or in Mexico. MRLs have been established 
in Canada on barley grain at 0.35 ppm and wheat grain at 0.07 ppm.

V. Conclusion

    Therefore, a tolerance is being revised for combined residues of 
prothioconazole, 2-[2-(1-chlorocyclopropyl)-3-(2-chlorophenyl)-2- 
hydroxypropyl]-1,2-dihydro-3H-1,2,4-triazole-3-thione, and 
prothioconazole-desthio, [alpha]-(1-chlorocyclopropyl)-[alpha]-[(2-
chlorophenyl)methyl]-1H-1,2,4-triazole-1-ethanol, calculated as parent, 
in or on wheat, forage, from 6.0 ppm to 8.0 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

[[Page 14749]]

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) (Public Law 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: March 19, 2009.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

0
Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

0
1. The authority citation for part 180 continues to read as follows:

    Authority: 21 U.S.C. 321(q), 346a and 371.

0
2. Section 180.626 is amended by revising the entry for ``wheat, 
forage'' in the table in paragraph (a)(1) to read as follows:

Sec.  180.626  Prothioconazole; tolerances for residues.

    (a) * * * (1) * * *

------------------------------------------------------------------------
                                                               Parts per
                          Commodity                             million
------------------------------------------------------------------------
                                * * * * *
Wheat, forage................................................          8
------------------------------------------------------------------------

* * * * *
[FR Doc. E9-7175 Filed 3-31-09; 8:45 am]

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