[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
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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
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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
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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
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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]
BILLING CODE 6560-50-S