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Acetochlor; Pesticide Tolerance

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[Federal Register: May 16, 2007 (Volume 72, Number 94)]
[Rules and Regulations]
[Page 27463-27469]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16my07-21]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[EPA-HQ-OPP-2006-0203; FRL-8126-2]

Acetochlor; Pesticide Tolerance

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

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SUMMARY: This regulation revises and separates the tolerances for
acetochlor in 180.470 into paragraphs (a) through (d) and reassigns
many of the current entries from paragraph (a) to paragraph (d), which
applies to tolerances for indirect and inadvertent residues. This
regulation also establishes several new tolerances and amends several
existing tolerances under paragraph (a). It further establishes several
new tolerances under paragraph (d); and amends and revises two
tolerances moved to that paragraph. Details of these changes are
outlined in Unit II. of this document. The Acetochlor Registration
Partnership (ARP) and Monsanto Company requested these changes as
submitted by petitions to EPA pursuant to the Federal Food, Drug and
Cosmetic Act (FFDCA).

DATES: This regulation is effective May 16, 2007. Objections and
requests for hearings must be received on or before July 16, 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-2006-0203. To access the
electronic docket, go to http://www.regulations.gov, select ``Advanced
Search,'' then ``Docket Search.'' Insert the docket ID number where
indicated and select the ``Submit'' button. Follow the instructions on
the regulations.gov web site to view the docket index or access
available documents. All documents in the docket are listed in the
docket index available in 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 telephone number
is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: Vickie Walters, Registration Division
(7505P), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone
number: (703) 305-5704; e-mail address: walters.vickie@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), e.g., agricultural
workers; greenhouse, nursery, and floriculture workers; farmers.
    • Animal production (NAICS code 112), e.g., cattle ranchers
and farmers, dairy cattle farmers, livestock farmers.
    • Food manufacturing (NAICS code 311), e.g., agricultural
workers; farmers; greenhouse, nursery, and floriculture workers;
ranchers; pesticide applicators.
    • Pesticide manufacturing (NAICS code 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 to
provide a guide for readers regarding entities likely to be

[[Page 27464]]

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 EPA's tolerance regulations at
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 FFDCA, 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-2006-0203 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 July 16, 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 this copy, identified by docket ID number
EPA-HQ-OPP-2006-0203, 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'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. Petition for Tolerance

    In the Federal Register of February 7, 2007 (72 FR 5706) (FRL-8111-
8, EPA issued a notice pursuant to section 408(d)(3) of FFDCA, 21
U.S.C. 346a(d)(3), announcing the filing of pesticide petitions (PP
1F6263, 4F4505, 6F4791) by the Acetochlor Registration Partnership
(ARP) and Monsanto Company, 1300 ``I'' St., NW., Washington, DC 20005,
and PP 5F6918 by Monsanto Company, 1300 ``I'' St., NW., Suite 450 East,
Washington, DC 20005. The petitions requested that 40 CFR 180.470(a) be
amended by establishing tolerances for residues of the herbicide,
acetochlor [2-chloro-2-methyl-6-ethyl-N-ethoxymethylacetamide) and its
metabolites containing the ethyl methyl aniline (EMA) moiety and the
hydroxyethyl methyl-aniline (HEMA) moiety, and expressed as acetochlor
equivalents in or on the food commodities corn, field, forage at 3.0
ppm (5F4505) corn, pop, grain at 0.05 part per million (ppm); corn,
pop, stover at 1.5 ppm (PP 1F6263); corn, sweet, fodder and forage at
1.5 ppm; and corn, sweet, kernels plus cob with husks removed at 0.05
ppm (6F4791); sorghum, forage at 1.0 ppm; sorghum, grain at 0.05 ppm;
and sorghum, grain, stover at 1.5 ppm (5F6918). These petitions also
requested that 40 CFR 180.470(d) be amended by establishing tolerances
for residues of the herbicide, acetochlor (2-chloro-2-methyl-6-ethyl-N-
ethoxymethylacetamide) and its metabolites containing the ethyl methyl
aniline (EMA) moiety and the hydroxyethyl methyl-aniline (HEMA) moiety,
and expressed as acetochlor equivalents in or on the food commodities
beet, sugar, root and tops/ pea and bean (except soybean) dried and
shelled (subgroup 6C)/potato/ and grain, cereal (except rice) (group
15),at 0.05 ppm; grain, grain, cereal (except rice), forage/fodder/
straw (group 16) forage at 0.5 ppm; grain, cereal (except rice) forage/
fodder/straw (group 16) hay at 2.0 ppm; grain, cereal (except rice)
forage/fodder/straw (group 16) stover at 0.1 ppm; grain, cereal (except
rice) forage/fodder/straw (group 16), straw at 0.3 ppm (1F6263); non-
grass animal feeds (group 18) forage at 1.3 ppm; and non-grass animal
feeds (group 18) hay at 3.5ppm (6F4791). That notice referenced a
summary of the petitions prepared by Acetochlor Registration
Partnership and Monsanto Company, the registrants, which have been
placed in the public docket, http://www.regulations.gov. There were no
comments received in response to the notice of filing.
    Based upon review of the data supporting the petitions EPA is
reassigning the entries for soybean, forage at 0.7 ppm; soybean, grain
at 0.1 ppm; soybean, hay at1.0 ppm; wheat, forage at 0.5 ppm; wheat,
grain at 0.02 ppm; and wheat, straw at 0.1 ppm; from 180.470(a) to
180.470(d) and establishing a tolerance for wheat, hay at 2.0 ppm under
40.CFR 180.470(d). The terminology for soybean, grain is being updated
to read soybean, seed to conform to Agency procedures. Additionally,
EPA is increasing the tolerance for corn, field, forage to 3.0 from 1.0
ppm. This tolerance will be listed in 180.470(a).
    Based upon review of the data submitted and Agency procedures
concerning commodity names, the Agency is correcting the terminology
for pending crops under 40 CFR 180.470(a) as follows: corn, field,
forage at 3.0 ppm; corn, pop, grain at 0.05 ppm; corn, pop, stover at
1.5 ppm; corn, sweet, kernels plus cob with husks removed at 0.05 ppm;
corn, sweet, forage at 1.5 ppm; and sorghum, grain, grain at 0.05 ppm.
The Agency is also correcting the tolerance levels and terminology for
pending crops under 40 CFR 180.470(a) as follows: corn, sweet, stover
at 1.0 ppm; sorghum, grain, forage at 1.6 ppm; sorghum, grain, grain at
0.05 ppm; and sorghum, grain, stover at 1.7 ppm. The above listings for
corn, field, forage; sorghum, grain, forage; sorghum, grain, grain; and
sorghum, grain, stover; replace the current listings for corn, field
forage; sorghum, forage; sorghum, grain; and sorghum, grain, stover.
    The Agency also determined that the tolerance expression and
correct terminology for the pending crops under 40 CFR 180.470(d)
should be written as follows: Tolerances are also established for
indirect or inadvertent residues of acetochlor (2-chloro-2'-methyl-6-
ethyl-N-ethoxymethylacetamide) and its metabolites containing the ethyl
methyl aniline (EMA) moiety and the hydroxyethyl methyl aniline (HEMA)
moiety, to be analyzed as acetochlor and expressed as acetochlor
equivalents, in or on the following raw agricultural commodities when
present therein as a

[[Page 27465]]

result of application of acetochlor to growing crops listed in
paragraph (a) of this section: Animal feed, nongrass, group 18, forage
at 1.3 ppm; animal feed, nongrass, group 18, hay at 3.5 ppm; beet,
sugar, root at 0.05 ppm; beet, sugar, tops at 0.05 ppm; grain, cereal,
group 15 except for corn, grain sorghum, rice and wheat, grain at 0.05
ppm; grain, cereal, forage, fodder and straw, group 16 except for corn,
grain sorghum, rice and wheat, forage at 0.5 ppm; grain, cereal,
forage, fodder and straw, group 16,except corn, grain sorghum, rice and
wheat, hay at 2.0 ppm; grain, cereal, forage, fodder and straw, Group
16, except corn, grain sorghum, rice and wheat, stover at 0.1 ppm;
grain, cereal, forage, fodder and straw, group 16, except corn, grain
sorghum, rice and wheat, straw at 0.3 ppm; pea and bean, dried shelled,
except soybean, subgroup 6C at 0.05 ppm; potato at 0.05; sunflower,
seed at 0.05 ppm and wheat, hay at 2.0 ppm.

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. . .
.'' These provisions were added to FFDCA by the Food Quality Protection
Act (FQPA) of 1996.
    Consistent with FFDCA section 408(b)(2)(D), and the factors
specified in section 408(b)(2)(D), 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
and amendments for tolerances for residues of acetochlor (2-chloro-2'-
methyl-6-ethyl-N-ethoxymethylacetamide) and its metabolites containing
the ethyl methyl aniline (EMA) moiety and the hydroxyethyl methyl
aniline (HEMA) moiety, to be analyzed as acetochlor and expressed as
acetochlor equivalents.

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 adverse effects caused by acetochlor as well as the no-observed-
adverse-effect-level (NOAEL) and the lowest-observed-adverse-effect-
level (LOAEL) from the toxicity studies can be found at 
http://www.regulations.gov. The referenced document is entitled
``Acetochlor-RED Phase 2 Revised HED Chapter of the TRED'' and is
available in the docket (EPA-HQ-OPP-2005-0227 identified as document 0004.

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no
appreciable risk, the toxicological level of concern (LOC) is derived
from 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 lowest
dose at which adverse effects of concern are identified (the LOAEL) is
sometimes used for risk assessment. Uncertainty/safety factors (UF) are
used in conjunction with the LOC 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
risks by comparing aggregate exposure to the pesticide to the acute
population adjusted dose (aPAD) and chronic population adjusted dose
(cPAD). The aPAD and cPAD are calculated by dividing the LOC by all
applicable uncertainty/safety factors. Short-, intermediate, and long-
term risks are evaluated by comparing aggregate exposure to the LOC to
ensure that the margin of exposure (MOE) called for by the product of
all applicable uncertainty/safety factors is not exceeded.
    For non-threshold risks, the Agency assumes that any amount of
exposure will lead to some degree of risk and estimates risk in terms
of the probability of occurrence of additional adverse cases.
Generally, cancer risks are considered non-threshold. 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/fedrgstr/EPA-PEST/1997/November/Day-26/p30948.htm.
    A summary of the toxicological endpoints for acetochlor used for
human risk assessment can be found at http://www.regulations.gov in document
Acetochlor: Human Health Risk Assessment to Support the Proposed Uses
on Sorghum and Sweet Corn and Rotational Crops of Nongrass Animal Feeds
(Group 18), Sugar Beets, Dried Shelled Beans and Peas (Subgroup 6C),
Sunflowers, Potatoes Cereal Grains (Group 15), and Forage, Fodder and
Straw of Cereal Grains (Group 16) on page 11 in Docket ID EPA-HQ-OPP-
2006-0203.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary
exposure to acetochlor, EPA considered exposure under the petitioned-
for tolerances as well as all existing acetochlor tolerances in (40 CFR
180.470). EPA assessed dietary exposures from acetochlor 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 USDA 1994-1996
and 1998 Nationwide Continuing Surveys of Food Intake by Individuals
(CSFII). As to residue levels in food, EPA assumed all foods for which
there are tolerances or for which tolerances are proposed, were treated
and contain tolerance-level residues. Experimentally derived processing
factors were used for cereal grain commodities. Default values were
used for all other processed commodities.
    ii. Chronic exposure. In conducting the chronic dietary exposure
assessment EPA used the food consumption data from the USDA 1994-1996
and 1998; Nationwide CSFII. As to residue levels in food, EPA chronic
dietary analysis included anticipated residues from field trial data
and assumed that all crop were treated. Experimentally derived
processing factors were used for cereal grain commodities. Default
values were used for all other processed commodities.
    iii. Cancer. Previously, EPA has treated acetochlor as a non-threshold

[[Page 27466]]

carcinogen and conducted a linear low-dose quantitative cancer risk
assessment in evaluating its safety. The determination that a
quantitative linear low-dose cancer assessment was appropriate was
based on findings that acetochlor caused mouse lung tumors and
histiocytic sarcomas in female mice. The Agency has reexamined the data
and concluded they do not support use of a quantitative linear low-dose
cancer assessment. The Agency determined that the relationship of the
mouse lung tumors to treatment was equivocal, due to some
inconsistencies in dose-response between the two available mouse
studies, the relatively frequent occurrence of the tumor in older mice
and the lack of evidence of direct genotoxicity of acetochlor. Further
the Agency found that the increase in the histiocytic sarcomas in
female mice in one study was also equivocal. EPA concludes that this
equivocal evidence of cancer shows no greater than a negligible risk of
cancer. Nonetheless, acetochlor has been associated with nasal tumors
in the rats and these tumors remain as a tumor of concern for human
exposure to acetochlor. Because, however, the nasal tumors have been
found to be a threshold effect, EPA has not used quantitative linear
low-dose cancer assessment in assessing this cancer risk. Rather, EPA
has relied on the chronic risk assessment because the chronic Reference
Dose (cRfD), which is based on a NOAEL of 2 milligrams/kilograms/day
(mg/kg/day), is considered to be protective of nasal tumors for which a
point of departure of 10 mg/kg/day was identified. EPA has used the
same exposure assumptions in assessing cancer risk as in assessing
other chronic risks.
    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 pursuant
to section 408(f)(1) of FFDCA require 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) of FFDCA 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.
    2. Dietary exposure from drinking water. The drinking water values
used in the dietary risk assessments were based on information provided
by the Acetochlor Registration Partner ship water monitoring program to
support the current use on field corn. The Agency has determined that
the new uses of acetochlor are not likely to result in concentrations
exceeding those seen in the field corn monitoring data; therefore this
data can be used to estimate drinking water concentrations resulting
from the new uses on sweet corn and sorghum. In the monitoring data,
exposure to acetochlor parent was significantly higher in the surface
water monitoring sites than the ground water monitoring sites;
therefore, the concentration used in the acute dietary assessment was
from a surface water monitoring site that produced the highest
concentration of 0.01821 ppm. The drinking water value used in the
chronic dietary risk assessment was from a surface water monitoring
site that produced the highest time-weighted annualized mean (TWAM)
concentration for a single year of 0.00143 ppm.
    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). Acetochlor is not
registered for use on any sites 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.''
    Acetochlor is a member of the chloroacetanilide cumulative
assessment group (CAG) which includes alachlor and butachlor. The
Agency previously conducted a cumulative risk assessment for the CAG
based on a common mode of action for the production of tumors of the
nasal olfactory epithelium in rats. Butachlor was determined to be part
of the CAG, however, there are currently no U.S. registrations for the
chemical; therefore, it was excluded from the cumulative risk
assessment. This risk assessment is fully discussed in the document:
Cumulative Risks from Chloroacetanilide Pesticides dated March 6, 2006
identified as document EPA-HQ-OPP-2005-0050-0061 which is available on
the internet at http://www.regulations.gov in docket number EPA-HQ-OPP-
2005-0050. Based on that cumulative risk assessment (CRA), the Agency
concluded that the cumulative risks from alachlor and acetochlor did
not exceed the Agency's level of concern since cumulative MOEs were
above 13,000 for all populations compared to a cumulative level of
concern of 100.
    For this risk assessment the Agency believes that the cumulative
risk from these new uses in addition to the current existing uses of
acetochlor and alachlor will not exceed The Agency's level of concern.
Individual risk assessments were conducted based on a point of
departure of 10 mg/kg/day for nasal tumors. Anticipated residues based
on field trial data and 100% crop treated was assumed for all existing
and new uses for acetochlor. The individual acetochlor assessment from
food resulted in MOEs raging from 49,000 for children 1-2 years old and
children 3-5 years old to 179,000 for adults 50+. The addition of water
to the assessment using surrogate data from the corn monitoring
studies, resulted in MOEs ranging from 40,000 for children 1-2 years
old to 116,000 for adults 50+. The MOEs for the General U.S. population
were 111,000 from food and 83,000 from both food and water.
    As noted in the March, 2006 cumulative risk assessment for the
chloroacetanilide chemicals, alachlor is the index chemical and
acetochlor is included in the assessment with a relative potency of 1/
20th of alachlor. Further, as noted in the cumulative risk assessment,
acetochlor commodities were not considered to be risk drivers in the
chloroacetanilide CRA; therefore given the individual MOEs for
acetochlor, it is unlikely that the addition of the new uses for
acetochlor will cause an unacceptable cumulative risk when considered
with the existing alachlor and acetochlor uses.

D. Safety Factor for Infants and Children

    1.In general. Section 408 of FFDCA provides that EPA shall apply an
additional (``10X'') 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 data base 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. In applying
this provision, EPA either retains the default value of 10X when
reliable data do not support the choice of a different

[[Page 27467]]

factor, or, if reliable data are available, EPA uses a different
additional FQPA safety factor value based on the use of traditional
uncertainty/safety factors and/or special FQPA safety factors, as
appropriate.
    2. Prenatal and postnatal sensitivity. Concern for prenatal and
postnatal susceptibility is low for acetochlor since toxicity to
offspring was observed only at maternal toxic doses in developmental
toxicity studies in the rat and rabbit and in three multi-generation
reproductive toxicity studies in the rat. In addition, clear NOAELS
were established in all of these three studies.
    3. Conclusion. A 10X FQPA safety factor was applied to the acute
dietary risk in the form of a database uncertainty factor to account
for the lack of a developmental neurotoxicity study. The following
findings support this determination.
    i. The toxicity database for acetochlor is not complete at this
time. A developmental neurotoxicity study is required based on
neurological observations, primarily in the dog or an alternative test
which addresses the sensitivity of the dog to neurological effects. In
addition, submission of positive control studies for validation of the
laboratory methodology used in the acute and subchronic rat oral
neurotoxicity screening studies is required as confirmatory data and to
upgrade those studies to acceptable.
    ii. Evidence of neurotoxicity from exposure to acetochlor was
observed in several studies. Salvation and other clinical signs
(anogential staining, diarrhea) were reported in some studies in both
the rat (two developmental studies) and the dog (subchronic and chronic
oral). The dog appears to be more sensitive than the rat or mouse to
effects on the nervous system, in that salivation occurred at lower
dose levels and frank neuropathology of the brain was observed in one
study. In the 1-year oral toxicity study in the dog pronounced
neurological signs (ataxia, abnormal head movements, tremor, depressed
righting, hoping and flexor reflexes, exaggerated tonic neck reflex and
stiffness and rigidity of the hindlimbs) were observed at the high dose
and were associated with degenerative lesions of the cerebellum. Other
evidence of neurotoxicity is discussed on page 46 of the document
entitled ``Acetochlor-RED Phase 2 Revised HED Chapter of the TRED''
which is available on the internet at http://www.regulations.gov in the
docket identified as EPA-HQ-OPP-2005-0227 document 0004.
    iii. The acute dietary endpoint of concern for the general
population including females 13-49 years of age, was derived from an
acute oral neurotoxicity screening study in rats (NOAEL of 150 mg/kg/
day based on decreased motor activity in females. Given the likely
dosing in the developmental neurotoxicity study, it is possible that
this study could lower the acute RfD by a factor of 10.
    EPA has determined that reliable data show that it would be safe
for infants and children to reduce the FQPA safety factor to 1X for the
chronic dietary risk. That decision is based on the following findings.
    • The toxicity database for acetochlor is complete other
than the lack of a developmental neurotoxicity study.
    • Given likely dosing in the developmental neurotoxicity
study, it is unlikely that this study would lower the cRFD. The chronic
dietary endpoint of concern for all populations was derived from the
chronic oral toxicity study in dogs with a NOAEL of 2 mg/kg/day based
on the increased salivation and histopathology in testes, kidney and
liver at 10 mg/kg/day. The cRFD of 2.0 mg/kg/day is less than the
NOAELs in the reproductive study of 21 mg/kg/day. A developmental
neurotoxicity study will likely be conducted at dose levels similar to
those of the 2-generation rat reproduction study. No evidence of
neuropathology or overt neurobehavioral effects were observed in the 2-
generation reproductive study with rats.
    • There is no evidence that acetochlor results in increased
susceptibility in in utero rats or rabbits in the prenatal
developmental studies or in young rats in the 2-generation reproduction
study. The FQPA safety factor was reduces to 1X.
    • There are no residual uncertainties identified in the
chronic exposure database. The chronic dietary food exposure assessment
was based on the assumption of all crops treated and anticipated
residues from acceptable field trial data for all commodities. For
chronic dietary food exposure assessments, experimentally derived
processing factors were used for cereal grain commodities and default
processing factors were used for all other processed commodities. The
drinking water values used in the dietary risk assessments were based
on information provided by the Acetochlor Registration Partnership
water monitoring program to support the current use on field corn.
These assessments will not underestimate the exposure and risks posed
by acetochlor.

E. Aggregate Risks and Determination of Safety

    Safety is assessed for acute and chronic risks by comparing
aggregate exposure to the pesticide to the aPAD and cPAD. The aPAD and
cPAD are calculated by dividing the LOC by all applicable uncertainty/
safety factors. For linear cancer risks, EPA calculates the probability
of additional cancer cases given aggregate exposure. Short-,
intermediate, and long-term risks are evaluated by comparing aggregate
exposure to the LOC to ensure that the MOE called for by the product of
all applicable uncertainty/safety factors is not exceeded.
    1. Acute risk. Using the exposure assumptions discussed in this
unit for acute exposure, the acute dietary exposure from food and water
to acetochlor will occupy < 1% of the aPAD at the 95th percentile for
the U.S. population and 2.6% of the aPAD at the 95th percentile for all
infants, the population subgroup receiving the greatest exposure.
    2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that exposure to
acetochlor from food and water will utilize < 1% of the cPAD for the
U.S. population and 1.2 % of the cPAD for children 1-2 years old, the
population subgroup receiving the greatest exposure. There are no
residential uses for acetochlor that result in chronic residential
exposure to acetochlor.
    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).
    Acetochlor is not registered for use on any sites that would result
in residential exposure. Therefore, an aggregate risk assessment for
this duration is not appropriate.
    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).
    Acetochlor is not registered for use on any sites that would result
in residential exposure. Therefore, an aggregate risk assessment for
this duration is not appropriate.
    5. Aggregate cancer risk for U.S. population. As explained above,
in Unit III.C.iii., the cRfD is considered to be protective of any
cancer risk posed by acetochlor and as discussed in Unit E2, EPA has
found that chronic acetochlor exposure does not exceed the cRfD;
therefore, aggregate cancer risks are not of concern.

[[Page 27468]]

    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 acetochlor residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    An adequate high performance liquid chromatography with oxidative
coulometric electrochemical detector (HPLC/OCED) method is available
for enforcing new tolerances for acetochlor and its metabolites in
sweet corn, sorghum, and rotational crops. This method is listed as
Method I for plants in PAM Vol. II.

B. International Residue Limits

    There are no Codex Maximum Residue Levels established for
acetochlor on agricultural commodities.

V. Conclusion

    Therefore, tolerances are established for residues of acetochlor
(2-chloro-2'-methyl-6-ethyl-N-ethoxymethylacetamide) and its
metabolites containing the ethyl methyl aniline (EMA) moiety and the
hydroxyethyl methyl aniline (HEMA) moiety to be analyzed as acetochlor,
and expressed as acetochlor equivalents as discussed in Unit II.

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, 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) 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 (59 FR 22951, November 6,
2000) do not apply to this rule. In addition, This 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: May 8, 2007.
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 180.470 is revised to read as follows:

Sec.  180.470  Acetochlor; tolerances for residues.

    (a) General. Tolerances are established for residues of acetochlor;
2-chloro-2'-methyl-6-ethyl-N-ethoxymethylacetanilide, and its
metabolites containing the ethyl methyl aniline (EMA) moiety and the
hydroxyethyl methyl aniline (HEMA) moiety, to be analyzed as acetochlor
and expressed as acetochlor equivalents, in or on the following raw
agricultural commodities.

------------------------------------------------------------------------
                      Commodity                        Parts per million
------------------------------------------------------------------------
Corn, field, forage..................................                3.0
Corn, field, grain...................................               0.05
Corn, field, stover..................................                1.5
Corn, pop, grain.....................................               0.05
Corn, pop, stover....................................                1.5
Corn, sweet, forage..................................                1.5
Corn, sweet, kernels plus cob with husks removed.....               0.05
Corn, sweet, stover..................................                1.0
Sorghum, grain, forage...............................                1.6
Sorghum, grain, grain................................               0.05
Sorghum, grain, stover...............................                1.7
------------------------------------------------------------------------

    (b) Section 18 emergency exemptions. [Reserved].
    (c) Tolerances with regional registrations. [Reserved].
    (d) Indirect or inadvertent residues. Tolerances are established
for indirect or inadvertent residues of acetochlor; 2-chloro-2'-methyl-
6-ethyl-N-ethoxymethylacetanilide, and its metabolites containing the
ethyl methyl aniline (EMA) moiety and the hydroxyethyl methyl aniline
(HEMA) moiety, to be analyzed as acetochlor and expressed as acetochlor
equivalents, in or on the following raw agricultural commodities when
present therein as a result of application of acetochlor to the growing
crops in paragraph (a) of this section:

[[Page 27469]]

------------------------------------------------------------------------
                                                            Parts per
                       Commodity                             million
------------------------------------------------------------------------
Animal feed, nongrass, group 18, forage...............               1.3
Animal feed, nongrass, group 18, hay..................               3.5
Beet, sugar, root.....................................              0.05
Beet, sugar, tops.....................................              0.05
Grain, cereal, forage, fodder and straw, group 16,                   0.5
 except corn, grain sorghum, rice and wheat, forage...
Grain, cereal, forage, fodder and straw, group 16,                   2.0
 except corn, grain sorghum, rice and wheat, hay......
Grain, cereal, forage, fodder and straw, group 16,                   0.1
 except corn, grain sorghum, rice and wheat, stover...
Grain, cereal, forage, fodder and straw, group 16,                   0.3
 except corn, grain sorghum, rice and wheat, straw....
Grain, cereal, group 15, except corn, grain sorghum,                0.05
 rice, and wheat, grain...............................
Pea and bean, dried shelled, except soybean, subgroup               0.05
 6C...................................................
Potato................................................              0.05
Soybean, forage.......................................               0.7
Soybean, hay..........................................               1.0
Soybean, seed.........................................               0.1
Sunflower, seed.......................................              0.05
Wheat, forage.........................................               0.5
Wheat, grain..........................................              0.02
Wheat, hay............................................               2.0
Wheat, straw..........................................               0.1
------------------------------------------------------------------------

[FR Doc. E7-9430 Filed 5-15-07; 8:45 am]
BILLING CODE 6560-50-S

 
 


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