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Myclobutanil; Pesticide Tolerance

 
[Federal Register: December 20, 2006 (Volume 71, Number 244)]
[Rules and Regulations]
[Page 76167-76173]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20de06-13]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[EPA-HQ-OPP-2006-0282; FRL-8105-1]

Myclobutanil; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for combined residues
of myclobutanil in or on hops, soybean seed, soybean forage, soybean
hay, aspirated grain fractions, and soybean refined oil. Interregional
Research Project #4 (IR-4) requested the tolerance for hops and
Dow AgroSciences requested the tolerances for the soybean commodities
under the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by
the Food Quality Protection Act of 1996 (FQPA).

DATES: This regulation is effective December 20, 2006. Objections and
requests for hearings must be received on or before February 20, 2007,
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-2006-0282. All documents in the
docket are listed in the index for the docket. 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 Building), 2777 S. Crystal Drive,
Arlington, VA. The Docket Facility is open from 8:30 a.m. to 4 p.m.,
Monday through Friday, excluding legal holidays. The Docket telephone
number is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: Barbara Madden, Registration Division
(7505P), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone
number: (703) 305-6463; e-mail address: madden.barbara@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:
    • Crop production (NAICS 111), e.g., agricultural workers;
greenhouse, nursery, and floriculture workers; farmers.
    • Animal production (NAICS 112), e.g., cattle ranchers and
farmers, dairy cattle farmers, livestock farmers.
    • Food manufacturing (NAICS 311), e.g., agricultural
workers; farmers; greenhouse, nursery, and floriculture workers;
ranchers; pesticide applicators.
    • Pesticide manufacturing (NAICS 32532), e.g., agricultural
workers; commercial applicators; farmers; greenhouse, nursery, and
floriculture workers; residential users.
    This listing is not intended to be exhaustive, but rather provides
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 an electronic copy of this Federal Register
document through the electronic docket 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 40 CFR part 180 through the Government Printing
Office's pilot e-CFR site at http://www.gpoaccess.gov/ecfr.

C. Can I File an Objection or Hearing Request?

    Under section 408(g) of the FFDCA, as amended by the FQPA, any
person may file an objection to any aspect of this regulation and may
also request a hearing on those objections. The EPA procedural
regulations which govern the submission of objections and requests for
hearings appear in 40 CFR part 178. 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-2006-0282 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 on or
before February 20, 2007.
    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 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 your copies, identified by docket ID
number EPA-HQ-OPP-2006-0282, by one of the following methods:
    • Federal eRulemaking Portal: http://www.regulations.gov.
Follow the on-line instructions for submitting comments.

[[Page 76168]]

    • 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
Building), 2777 S. Crystal Drive, Arlington, VA. Deliveries are only
accepted during the Docket'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 telephone number is (703) 305-5805.

II. Background and Statutory Findings

    In the Federal Register of April 12, 2006 (71 FR 18740) (FRL-7773-9), 
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
1E6265) by Interregional Research Project No. 4 (IR-4), 500 College
Road East, Suite 201 W, Princeton, NJ 08540. The petition requested
that 40 CFR 180.443 be amended by establishing a tolerance for combined
residues of the fungicide myclobutanil, alpha-butyl-alpha-(4-
chlorophenyl)-1H-1,2,4-triazole-1-propanenitrile and its alcohol
metabolite (alpha-(3-hydroxybutyl)-alpha-(4-chlorophenyl)-1H-1,2,4-
triazole-1-propanenitrile (free and bound), in or on hop, dried cones
at 10 parts per million (ppm). That notice included a summary of the
petition prepared by Dow AgroSciences, the registrant. There were no
comments received in response to the notice of filing.
    In the Federal Register of August 23, 2006 (71 FR 49448) (FRL-8073-2), 
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
5F6997) by Dow AgroSciences, 9330 Zionsville Road, Indianapolis, IN
46268. The petition requested that 40 CFR 180.443 be amended by
establishing tolerances for combined residues of the fungicide
myclobutanil, alpha-butyl-alpha-(4-chlorophenyl)-1H-1,2,4-triazole-1-
propanenitrile and its alcohol metabolite (alpha-(3-hydroxybutyl)-
alpha-(4-chlorophenyl)-1H-1,2,4-triazole-1-propanenitrile (free and
bound), in or on soybean, aspirated grain fractions at 1.1 ppm;
soybean, forage at 5.0 ppm; soybean, hay at 13.0 ppm; soybean, hulls at
0.06 ppm; soybean, meal at 0.03 ppm; soybean, oil at 0.1 ppm; and
soybean, seed at 0.05 ppm. That notice included a summary of the
petition prepared by Dow AgroSciences, the registrant. There were no
comments received in response to the notice of filing.
    Upon completing review of the current myclobutanil database, the
Agency concluded that the appropriate tolerance levels for myclobutanil
residues in or on pending crops should be established as follows: Hop,
dried cones at 10 ppm; soybean, seed at 0.25 ppm; soybean, forage at
3.5 ppm; soybean, hay at 15 ppm; aspirated grain fractions at 35 ppm;
and soybean, refined oil at 0.40 ppm. In addition, the proposed
tolerances for soybean, hulls and soybean, meal were withdrawn because
based on available processing data, tolerances for these commodities
are not needed.
    EPA is also deleting several established tolerances in 40 CFR
180.443(b) that are no longer needed as a result of this action. The
tolerance deletions under 40 CFR 180.443(b) are time-limited tolerances
established under section 18 emergency exemptions that are superseded
by the establishment of general tolerances for myclobutanil and its
metabolites under 40 CFR 180.443(a).
    The revisions to 40 CFR 180.443(b) are as follows:
    Delete the time-limited tolerance for hop, dried cone at 5.0 ppm. A
tolerance for hop, dried cones at 10 ppm is established by this action
under 40 CFR 180.443(a).
    Delete the time-limited tolerance for soybean at 0.05 ppm. A
tolerance for soybean, seed at 0.25 ppm is established by this action
under 40 CFR 180.443(a).
    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....''
    EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 of the FFDCA and a complete
description of the risk assessment process, see 
http://www.epa.gov/fedrgstr/EPA-PEST/1997/November/Day-26/p30948.htm.

III. Aggregate Risk Assessment and Determination of Safety

    Consistent with 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, consistent with section
408(b)(2) of FFDCA, for tolerances for combined residues of
myclobutanil alpha-butyl-alpha-(4-chlorophenyl)-1H-1,2,4-triazole-1-
propanenitrile and its alcohol metabolite (alpha-(3-hydroxybutyl)-
alpha-(4-chlorophenyl)-1H-1,2,4-triazole-1-propanenitrile (free and
bound), in or on hop, dried cones at 10 ppm; soybean, seed at 0.25 ppm;
soybean, forage at 3.5 ppm; soybean, hay at 15 ppm; grain, aspirated
fractions at 35 ppm; and soybean, refined oil at 0.40 ppm. EPA's
assessment of exposures and risks associated with establishing these
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. Specific information on the studies received and the nature
of the toxic effects caused by myclobutanil 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.epa.gov/fedrgstr/EPA-PEST/2000/May/Day-10/p11571.htm
(Federal Register of May 10, 2000 (65 FR 29963) (FRL-6555-5).

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no
appreciable risk, the NOAEL from the toxicology study identified as
appropriate for use in risk assessment is used to estimate the
toxicological level of concern (LOC). However, the LOAEL is sometimes
used for risk assessment if no NOAEL was achieved in the toxicology
study selected. An uncertainty factor (UF) is applied to reflect
uncertainties inherent in the extrapolation from laboratory

[[Page 76169]]

animal data to humans and in the variations in sensitivity among
members of the human population as well as other unknowns.
    The linear default risk methodology (Q*) is the primary method
currently used by the Agency to quantify non-threshold hazards such as
cancer. The Q* approach assumes that any amount of exposure will lead
to some degree of cancer risk, estimates risk in terms of the
probability of occurrence of additional cancer cases. More information
can be found on the general principles EPA uses in risk
characterization at http://www.epa.gov/pesticides/health/human.htm.

    A summary of the toxicological endpoints for myclobutanil used for
human risk assessment can be found at http://www.regulations.gov in document
0002 (pages 6 and 7) in docket ID number EPA-HQ-OPP-2006-0282. To
locate this information on the Regulations.gov website follow these steps:
    • Select ``Advanced Search'', then ``Docket Search''
    • In the ``Keyword'' field type the chemical name or insert
the applicable ``Docket ID number.'' (example: EPA-HQ-OPP-2005-9999)
    • Click the ``Submit'' button.
     Follow the instructions on the regulations.gov web site to view
the index for the docket and access available documents.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. Tolerances have been
established (40 CFR 180.443) for the combined residues of myclobutanil,
in or on a variety of raw agricultural commodities. Tolerances have
also been established for combined residues of myclobutanil in or on
milk, egg, and fat, liver, meat, and meat byproducts of cattle, goat,
hog, horse, and sheep as well as fat, meat, and meat byproducts of
poultry. Risk assessments were conducted by EPA to assess dietary
exposures from myclobutanil 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 one-day or single exposure.
    An acute dietary exposure assessment was performed for females 13-
49 years old (no endpoint was identified for the general U.S.
population or any other population subgroup). In conducting the acute
dietary exposure assessment EPA used the Dietary Exposure Evaluation
Model software with the Food Commodity Intake Database (DEEM-FCID\TM\),
which incorporates food consumption data as reported by respondents in
the United States Department of Agriculture (USDA) 1994-1996 and 1998
Nationwide Continuing Surveys of Food Intake by Individuals (CSFII),
and accumulated exposure to the chemical for each commodity. The
following assumptions were made for the acute exposure assessments:
Tolerance-level residues and 100 percent crop treated (PCT) information
for all registered and proposed uses.
    ii. Chronic exposure. In conducting the chronic dietary exposure
assessment EPA used the Dietary Exposure Evaluation Model software with
the Food Commodity Intake Database (DEEM-FCID\TM\), which incorporates
food consumption data as reported by respondents in the USDA 1994-1996
and 1998 Nationwide Continuing Surveys of Food Intake by Individuals
(CSFII), and accumulated exposure to the chemical for each commodity.
The following assumptions were made for the chronic exposure
assessments: A partially refined, chronic dietary exposure assessment
was performed for the general U.S. population and various population
subgroups using USDA Pesticide Data Program (PDP) monitoring data for
apple juice, bananas (not plantains) and milk and assuming all other
commodities covered by registered and proposed tolerances have residues
at the appropriate tolerance value. Average PCT information was used
for apple (except juice), apricots, asparagus, blackberry, cantaloupe,
cherry, cucumber, grape, nectarine, peach, plum, pumpkin, raspberry,
squash, strawberry, tomato, and watermelon; 100 PCT was assumed for all
other registered and proposed uses.
    iii. Cancer. The Agency has classified myclobutanil as Group E -
not likely to be a human carcinogen. Myclobutanil was determined to be
not carcinogenic in two acceptable animal studies. Therefore, a cancer
dietary exposure assessment was not performed.
    iv. Anticipated residue and PCT information. 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 the Agency can
make the following findings: Condition 1, that 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 such pesticide residue;
Condition 2, that the exposure estimate does not underestimate exposure
for any significant subpopulation group; and Condition 3, if 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 section 408(b)(2)(F)
of FFDCA, EPA may require registrants to submit data on PCT.
    The Agency used PCT information as follows:
    40% of apples (except juice), 25% of apricots, 5% of asparagus, 15%
of blackberry, 10 % of cantaloupe, 35 % of cherry, 1% of cucumber, 25%
of grape, 15% of nectarine, 10% of peach, 10% of plum, 15% of pumpkin,
25% of raspberry, 10% of squash, 35% of strawberry, 5% of tomato, and
5% of watermelon.
    EPA uses an average PCT for chronic dietary risk analysis. The
average PCT figure for each existing use is derived by combining
available federal, state, and private market survey data for that use,
averaging by year, averaging across all years, and rounding up to the
nearest multiple of five percent except for those situations in which
the average PCT is less than one. In those cases < 1% is used as the
average and < 2.5% is used as the maximum.
    EPA uses a maximum PCT for acute dietary risk analysis. The maximum
PCT figure is the single maximum value reported overall from available
federal, state, and private market survey data on the existing use,
across all years, and rounded up to the nearest multiple of five
percent. In most cases, EPA uses available data from USDA/National
Agricultural Statistics Service (USDA/NASS), Proprietary Market
Surveys, and the National Center for Food and Agriculture Policy
(NCFAP) for the most recent six years.
    The Agency believes that the three conditions listed in Unit
III.C.iv. have been met. With respect to Condition 1, 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 2 and 3, 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

[[Page 76170]]

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 information on the regional consumption of food to
which myclobutanil may be applied in a particular area.
    3. Dietary exposure from drinking water. The Agency lacks
sufficient monitoring exposure data to complete a comprehensive dietary
exposure analysis and risk assessment for myclobutanil in drinking
water. Because the Agency does not have comprehensive monitoring data,
drinking water concentration estimates are made by reliance on
simulation or modeling taking into account data on the physical
characteristics of myclobutanil. 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 PRZM/EXAMS and SCI-GROW models, the estimated
environmental concentrations (EECs) of myclobutanil for acute exposures
are estimated to be 15.3 parts per billion (ppb) for surface water and
0.35 ppb for ground water. The EECs for chronic exposures are estimated
to be 8.5 ppb for surface water and 0.35 ppb for ground water.
    Modeled estimates of drinking water concentrations were directly
entered into the dietary exposure model (DEEM-FCID\TM\). The estimates
were calculated using the application rate for hops, which has the
highest use rate among all existing and proposed uses. For acute
dietary risk assessment the 1- in 10-year peak acute of 15.3 ppb was
used to assess the contribution to drinking water and for chronic
dietary risk assessment the 1- in 10-year estimated annual mean of 8.5
ppb was used to assess the contribution to drinking water.
    4. 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).
    Myclobutanil is currently registered for use on the following
residential non-dietary sites: Turf, ornamentals, and home garden uses
on fruit trees, nut trees, berries, mint and vegetables. The risk assessment
was conducted using the following residential exposure assumptions:
    The homeowner use with the greatest potential for exposure is
small-scale lawn application. Since myclobutanil is applied at 7- to
14-day intervals, only short-term exposure is expected for the
residential handler. Short- and intermediate-term residential post-
application exposures are also expected.
    The current use patterns and labeling indicate that a variety of
application equipment could be used by the homeowner to apply
myclobutanil to ornamental plants, shrubs, fruit trees, home garden
vegetables and lawns. Therefore, the following scenarios were assessed:
    i. Aerosol Spray Can Application to Ornamentals and Fruit Trees
    ii. Hose End Sprayer Application to Ornamentals and Fruit Trees
    iii. Low-pressure (LP) Handwand Application to Ornamentals
    iv. LP Handwand Application to Vegetables
    v. Ready to use (RTU) Sprayer Application to Vegetables
    vi. Hose End Sprayer Application to Vegetables
    vii. Hose End Sprayer - Mix Your Own - Application to Turf
    viii. Hose End Sprayer - Ready to Use - Application to Turf
    ix. Belly Grinder Application to Turf
    x. Broadcast Spreader Application to Turf
    Unit exposure data were either taken from Pesticide Handler's
Exposure Database (PHED) or from the home garden and turf application
studies that were sponsored by the Outdoor Residential Exposure Task
Force (ORETF).
    Home garden post-application exposures can occur when home
gardeners perform tasks such as weeding, pruning or hand harvesting
following application of myclobutanil. In order to address these risks,
the post-application exposure to home gardens and orchard scenarios
were assessed based upon the Residential standard operating procedures
(SOP) 3.0 for Garden Plants and SOP 4.0 for Trees.
    Two dislodgeable foliar residue (DFR) studies on grapes in
California were used to assess the home garden exposures. The studies
were performed using airblast sprayers while the proposed home garden
applications would be made with LP handwand or hose end sprayers. Based
upon experience with other fungicides, however, it is anticipated that
DFRs resulting from handwand applications would be similar to DFRs from
airblast applications. The initial DFR was assumed to be 23% of the
application rate.
    ``Pick your own'' exposures can occur at commercially operated
``pick your own'' strawberry farms and orchards where myclobutanil has
been applied. To address these risks, post-application exposure for
pick your own strawberries and tree fruit were assessed based upon the
Residential SOP 15.0 for ``pick your own'' strawberries. The DFR data
that were used for the home gardener post-application risks were also
used to assess ``pick your own'' exposures. The exposure estimates used
for pick your own exposures are considered conservative because that
scenario is based upon a screening-level transfer coefficient (TC) and
a dermal absorption factor of 50%.
    The following scenarios were assessed for residential turf post-
application exposures and risks:
    a. Toddlers Playing on Treated Turf
    b. Adults Performing Yard work on Treated Turf
    c. Adults Playing Golf on Treated Turf
    A turf transferable residue (TTR) study was used to assess the turf
exposures. The field portion of this study was in North Carolina and
California. The initial TTR for dermal exposures was assumed to be 2.4%
of the application rate and was based upon an average of the days after
treatment (DAT) of 0 and DAT of 3 for the California site. The maximum
application rate for turf of 0.62-0.68 pounds active ingredient per
acre (lb ai/A) was use to assess the turf exposures.
    Additional information on residential exposure assumptions can be
found at http://www.regulations.gov (Docket ID number EPA-HQ-OPP-2006-
0282-0005, pages 13 through 17).
    5. Cumulative effects from substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) of the 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.''
    Myclobutanil is a member of the triazole-containing class of
pesticides. Although conazoles 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 (EPA, 2002). In conazoles, however, a variable
pattern of toxicological responses is found. Some are hepatotoxic and
hepatocarcinogenic in mice. Some induce thyroid tumors in rats. Some

[[Page 76171]]

induce developmental, reproductive, and neurological effects in
rodents. Furthermore, the conazoles 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 conazoles share common mechanisms of toxicity and EPA is
not following a cumulative risk approach based on a common mechanism of
toxicity for the conazoles. For information regarding EPA's procedures
for cumulating effects from substances found to have a common mechanism
of toxicity, see EPA's website at 
http://www.epa.gov/pesticides/cumulative.
    Myclobutanil is a triazole-derived pesticide. This class of
compounds can form the common metabolite 1,2,4-triazole and two
triazole conjugates (triazole alanine and triazole acetic acid). To
support existing tolerances and to establish new tolerances for
triazole-derivative pesticides, including myclobutanil, U.S. 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.
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 in the propiconazole
reregistration docket 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 of FFDCA provides that EPA shall apply
an additional tenfold 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. Margins of safety are
incorporated into EPA risk assessments either directly through use of a
MOE analysis or through using uncertainty (safety) factors in
calculating a dose level that poses no appreciable risk to humans. In
applying this provision, EPA either retains the default value of 10X
when reliable data do not support the choice of a different factor, or,
if reliable data are available, EPA uses a different additional safety
factor value based on the use of traditional uncertainty factors and/or
special FQPA safety factors, as appropriate.
    2. Prenatal and postnatal sensitivity. There is no indication of
quantitative or qualitative increased susceptibility in rats or rabbits
from in utero and/or postnatal exposure to myclobutanil. In the rat
developmental toxicity study, maternal toxicity, which included rough
hair coat and salivation, alopecia, desquamation and red exudate around
mouth occurs at the same dose level as increases in incidences of 14th
rudimentary and 7th cervical ribs in the fetuses. The maternal and
developmental toxicity NOAELs in the rat developmental toxicity study
were 93.8 mg/kg/day. EPA concludes that there is no evidence
qualitative susceptibility in rat developmental toxicity study since
the fetal variations (14th rudimentary ribs and 7th cervical ribs) are
normal occurance control animals that occurred in the presence severe
maternal toxicity (red exudate around mouth and salivation). In the
rabbit developmental toxicity study there is reduced body weight and
body weight gain during the dosing period, clinical signs of toxicity
such as bloody urine and bloody urogenital or anal area and a possible
increase in abortions (blood and/or aborted material in the cage pan)
in the does at the same dose level as developmental toxicity manifested
as increased resorptions, decreased litter size and decreased viability
index. The maternal and developmental toxicity NOAELs in the rabbit
developmental toxicity study were 93.8 mg/kg/day. EPA concludes that
there is no evidence qualitative susceptibility in rabbit developmental
toxicity study since the fetal effects (resorptions, decreased litter
size and viability) occurred in the presence equally severe maternal
toxicity (abortions, bloody urine and bloody urogenital or anal area).
The maternal NOAEL in the 2-generation reproduction study was 50 ppm
(2.5 mg/kg/day) based on hepatocellular hypertrophy and increased in
liver weight seen at 200 ppm (10 mg/kg/day; LOAEL). The offspring
toxicity NOAEL was 200 ppm (10 mg/kg/day) based on decreased in pup
body weight gain during lactation seen at 1,000 ppm (50 mg/kg/day;
LOAEL). The reproductive toxicity NOAEL was 200 ppm (10 mg/kg/day)
based on increased incidences in the number of still born pups and
atrophy of the testes, epididymides and prostate observed at 1,000 ppm
(50 mg/kg/day; LOAEL). EPA concludes that there is no evidence on
increased susceptibility (qualitative or quantitative) in the 2-
generation reproduction study in rats because the offspring and
reproductive toxicity were observed at a higher dose than the dose that
caused maternal toxicity.
    3. Conclusion. EPA has determined that reliable data show that it
would be safe for infants and children to reduce the FQPA safety factor
to 1X. The decision is base on the following findings:
    i. There is a complete toxicity data base for myclobutanil.
    ii. There was no evidence of increased susceptibility in the
developmental toxicity studies with rats and rabbits.
    iii. A developmental neurotoxicity study is not required because
neurotoxic compounds of similar structure were not identified and there
was no evidence of neurotoxicity in the current toxicity database.
    iv. The exposure assessments will not underestimate the potential
dietary (food and drinking water) and residential (non-occupational)
exposures for infants and children from the use of myclobutanil.
    v. The acute dietary food exposure assessment (females 13-49 years
old only) utilizes existing and proposed tolerance level residues and
100 PCT information for all commodities. By using these screening-level
assessments, actual exposures/risks will not be underestimated.
    vi. The chronic dietary food exposure assessment utilizes existing
and proposed tolerance level residues; USDA Pesticide Data Program
(PDP) monitoring data for apple juice, bananas (not plantains) and
milk; average PCT data for some commodities and 100 PCT information for
all other registered and proposed uses. The chronic assessment is
somewhat refined and based on reliable data and will not underestimate
exposure/risk.
    vii. The dietary drinking water assessment utilizes water
concentration values generated by model and associated modeling
parameters, which are designed to provide conservative, health
protective, high-end estimates of water concentrations which will not
likely be exceeded.
    viii. The residential handler assessment is based upon the
residential SOPs and utilized unit exposure data

[[Page 76172]]

from the ORETF and the PHED. The residential post-application
assessment is based upon chemical-specific turf transferable residue
(TTR) data and DFR data. The chemical-specific study data as well as
the surrogate study data used are reliable and also are not expected to
underestimate risk to adults as well as to children. In a few cases
where chemical-specific data were not available, the SOPs were used
alone. The residential SOPs are based upon reasonable ``worst-case''
assumptions and are not expected to underestimate risk. These
assessments of exposure are not likely to underestimate the resulting
estimates of risk from exposure to myclobutanil.

 E. Aggregate Risks and Determination of Safety

    1. Acute risk. Using the exposure assumptions discussed in this
unit for acute exposure, the acute dietary exposure from food and water
to myclobutanil will occupy 2.4% of the acute Adjusted Population Dose
(aPAD) for females 13 years and older. No endpoint was identified for
the general U.S. population or any other population subgroup.
Therefore, EPA does not expect the aggregate exposure to exceed 100% of
the aPAD.
    2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that exposure to
myclobutanil from food and water will utilize 10% of the chronic
Population Adjusted Dose (cPAD) for the U.S. population, 17% of the
cPAD for all infants less that 1 year old, and 25% of the cPAD for
children 1-2 years old, the subpopulation at greatest exposure. There
are no residential uses for myclobutanil that result in chronic
residential exposure. Therefore, chronic residential exposure to
residues of myclobutanil is not expected. EPA does not expect the
aggregate exposure to exceed 100% of the cPAD.
    3. Short-term risk. Short-term aggregate exposure takes into
account residential exposure plus chronic exposure to food and water
(considered to be a background exposure level). The short-term
aggregate risk assessments estimate risks likely to result from 1-30
days of exposure to myclobutanil residues in food, drinking water, and
residential pesticide uses.
    Myclobutanil 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 food, water and short-term
exposures for myclobutanil.
    Using the exposure assumptions described in this unit for short-
term exposures, EPA has concluded that food, water and residential
exposures aggregated result in aggregate margin of exposures (MOEs) of
180 for the general U.S. population for handler exposures; 300 for the
general U.S. population for home gardens post application exposures;
110 for the general U.S. population for ``Pick Your Own'' fruit tree
post application exposures; 130 for the general U.S. population for
heavy yard work for turf post application exposures; 1,300 for the
general U.S. population for exposures when playing golf and 130 for
children 1-2 years old when playing on the lawn post application
exposures. These aggregate MOEs do not exceed the Agency's LOC for
aggregate exposure to food, water and residential uses. Therefore, EPA
does not expect short-term aggregate exposure to exceed the Agency's LOC.
    4. Intermediate-term risk. Intermediate-term aggregate exposure
takes into account residential exposure plus chronic exposure to food
and water (considered to be a background exposure level). The
intermediate-term aggregate risk assessment estimates risks likely to
result from 1 to 6 months exposure to myclobutanil residues in food,
drinking water, and residential pesticide scenarios.
    Myclobutanil 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 food and water and
intermediate-term exposures for myclobutanil.
    Using the exposure assumptions described in this unit for
intermediate-term exposures, EPA has concluded that food, water, and
residential exposures aggregated result in aggregate MOEs of 300 for
the general U.S. population for home garden post application exposures;
110 for the general U.S. population for ``Pick Your Own'' fruit tree
post application exposures; 130 for the general U.S. population for
heavy yard work for turf post application exposures; 1,300 for the
general U.S. population for exposures when playing golf and 130 for
children 1-2 years old when playing on the lawn post application
exposures. These aggregate MOEs do not exceed the Agency's LOC for
aggregate exposure to food, water, and residential uses. Therefore, EPA
does not expect intermediate-term aggregate exposure to exceed the
Agency's LOC.
    5. Aggregate cancer risk for U.S. population. The Agency has
classified myclobutanil as Group E - not likely to be a human
carcinogen. Myclobutanil was determined to be not carcinogenic in two
acceptable animal studies. Myclobutanil 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, and to infants and children from aggregate
exposure to myclobutanil residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    An adequate enforcement method is available to enforce the proposed
tolerances on soybeans and hops. Quantitation is by gas-liquid
chromatography (GLC) using a nitrogen/phosphorus (N/P) detector for
myclobutanil and an electron capture detector (Ni63) for residues
measured as the alcohol metabolite. The EPA has conducted a successful
method validation of Method 34S-88-10, and the method has been
forwarded to the Food and Drug Administration (FDA) for inclusion in
Pesticide Analytical Method Volume II (PAM) Vol. II.
    Enforcement methods for the established tolerances on livestock
commodities are Methods 34S-88-22, 34S-88-15, 31S-87-02, and 34S-88-21
These methods have been submitted for publication in PAM II.
    These 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 current Codex, Canadian or Mexican maximum residue
limits (MRLs) for residues of myclobutanil in/on soybeans. Therefore,
harmonization is not an issue. There are no current Canadian or Mexican
maximum residue limits (MRLs) for residues of myclobutanil in/on hops.
However, there is a Codex MRL of 2 ppm for the parent compound
myclobutanil in/on hops, dry. EPA has concluded the submitted residue
chemistry data support a tolerance of 10 ppm for residues of
myclobutanil and its alcohol metabolite RH-9090 (free and bound).
Therefore, harmonization with the Codex MRL is not possible.

V. Conclusion

    Therefore, tolerances are established for combined residues of
myclobutanil alpha-butyl-alpha-(4-chlorophenyl)-1H-1,2,4-triazole-1-
propanenitrile and its alcohol metabolite (alpha-(3-hydroxybutyl)-
alpha-(4-chlorophenyl)-1H-1,2,4-triazole-1-propanenitrile (free

[[Page 76173]]

and bound), in or on hop, dried cones at 10 ppm; soybean, seed at 0.25
ppm; soybean, forage at 3.5 ppm; soybean, hay at 15 ppm; grain,
aspirated fractions at 35 ppm; and soybean, refined oil at 0.40 ppm.

VI. Statutory and Executive Order Reviews

    This final rule establishes a tolerance 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 rule has been
exempted from review under Executive Order 12866 due to its lack of
significance, this rule is not subject to Executive Order 13211,
Actions Concerning Regulations That Significantly Affect Energy Supply,
Distribution, or Use (66 FR 28355, May 22, 2001). 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., or 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). 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); or OMB review or any Agency action under Executive
Order 13045, entitled Protection of Children from Environmental Health
Risks and Safety Risks (62 FR 19885, April 23, 1997). 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). 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. In addition, the Agency has determined that this
action will not have a substantial direct effect on States, on the
relationship between the national government and the States, or on the
distribution of power and responsibilities among the various levels of
government, as specified in Executive Order 13132, entitled Federalism
(64 FR 43255, August 10, 1999). Executive Order 13132 requires EPA to
develop an accountable process to ensure ``meaningful and timely input
by State and local officials in the development of regulatory policies
that have federalism implications.'' ``Policies that have federalism
implications'' is defined in the Executive order to include regulations
that have ``substantial direct effects on the States, on the
relationship between the national government and the States, or on the
distribution of power and responsibilities among the various levels of
government.'' This final rule directly regulates growers, food
processors, food handlers and food retailers, not States. This action
does not alter the relationships or distribution of power and
responsibilities established by Congress in the preemption provisions
of section 408(n)(4) of FFDCA. For these same reasons, the Agency has
determined that this rule does not have any ``tribal implications'' as
described in Executive Order 13175, entitled Consultation and
Coordination with Indian Tribal Governments (59 FR 22951, November 6,
2000). Executive Order 13175, requires EPA to develop an accountable
process to ensure ``meaningful and timely input by tribal officials in
the development of regulatory policies that have tribal implications.''
``Policies that have tribal implications'' is defined in the Executive
order to include regulations that have ``substantial direct effects on
one or more Indian tribes, on the relationship between the Federal
Government and the Indian tribes, or on the distribution of power and
responsibilities between the Federal Government and Indian tribes.''
This rule will not have substantial direct effects on tribal
governments, on the relationship between the Federal Government and
Indian tribes, or on the distribution of power and responsibilities
between the Federal Government and Indian tribes, as specified in
Executive Order 13175. Thus, Executive Order 13175 does not apply to
this rule.

VII. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
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: December 8, 2006.
Donald R. Stubbs,
Acting Director, Registration Division, Office of Pesticide Programs.

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

PART 180--[AMENDED]

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

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

• 2. Section 180.443 is amended:
• a. In paragraph (a), in the table, by alphabetically adding commodities
to read as set forth below; and
• b. In paragraph (b), in the table, by removing the commodities ``Hop,
dried cone'' and ``Soybean''.

Sec.  180.443   Myclobutanil; tolerances for residues.

    (a) * * *

------------------------------------------------------------------------
                                                              Parts per
                         Commodity                             million
------------------------------------------------------------------------
                                * * * * *
Grain, aspirated fractions.................................           35
                                * * * * *
Hop, dried cones...........................................           10
                                * * * * *
Soybean, forage............................................          3.5
 Soybean, hay..............................................           15
Soybean, refined oil.......................................         0.40
Soybean, seed..............................................         0.25
------------------------------------------------------------------------

* * * * *
[FR Doc. E6-21489 Filed 12-19-06; 8:45 am]
BILLING CODE 6560-50-S 

 
 


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