Document ID: EPA-HQ-OPP-2009-0002-0004
Agency: epa
Document Type: Rule
Title: Acetochlor; Pesticide Tolerances
Posted Date: 2009-09-16T04:00Z

[Federal Register: September 16, 2009 (Volume 74, Number 178)]
[Rules and Regulations]               
[Page 47445-47451]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16se09-6]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2009-0002; FRL-8434-1]

 
Acetochlor; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for residues of 
acetochlor, including its metabolites and degradates, in or on cotton, 
gin byproducts; cotton, undelinted seed; soybean, meal; and soybean, 
seed. Monsanto Company requested these tolerances under the Federal 
Food, Drug, and Cosmetic Act (FFDCA). This regulation also removes the 
existing tolerance for indirect or inadvertent residues of acetochlor 
on soybean, seed.

DATES: This regulation is effective September 16, 2009. Objections and 
requests for hearings must be received on or before November 16, 2009, 
and must be filed in accordance with the instructions provided in 40 
CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).

ADDRESSES: EPA has established a docket for this action under docket 
identification (ID) number EPA-HQ-OPP-2009-0002. All documents in the 
docket are listed in the docket index available at http://
www.regulations.gov. Although listed in the index, some information is 
not publicly available, e.g., Confidential Business Information (CBI) 
or other information whose disclosure is restricted by statute. Certain 
other material, such as copyrighted material, is not placed on the 
Internet and will be publicly available only in hard copy form. 
Publicly available docket materials are available in the electronic 
docket at http://www.regulations.gov, or, if only available in hard 
copy, at the OPP Regulatory Public Docket in Rm. S-4400, One Potomac 
Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The Docket 
Facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. The Docket Facility telephone number is (703) 
305-5805.

FOR FURTHER INFORMATION CONTACT: Susan Stanton, Registration Division 
(7505P), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 305-5218; e-mail address: stanton.susan@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you are an 
agricultural producer, food manufacturer, or pesticide manufacturer. 
Potentially affected entities may include, but are not limited to those 
engaged in the following activities:
     Crop production (NAICS code 111).
     Animal production (NAICS code 112).
     Food manufacturing (NAICS code 311).
     Pesticide manufacturing (NAICS code 32532).
    This listing is not intended to be exhaustive, but rather to 
provide a guide for readers regarding entities likely to be affected by 
this action. Other types of entities not listed in this unit could also 
be affected. The North American Industrial Classification System 
(NAICS) codes have been provided to assist you and others in 
determining whether this action might apply to certain entities. If you 
have any questions regarding the applicability of this action to a 
particular entity, consult the person listed under FOR FURTHER 
INFORMATION CONTACT.

B. How Can I Access Electronic Copies of this Document?

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

C. Can I File an Objection or Hearing Request?

    Under section 408(g) of FFDCA, 21 U.S.C. 346a, any person may file 
an objection to any aspect of this regulation and may also request a 
hearing on those objections. You must file your objection or request a 
hearing on this regulation in accordance with the instructions provided 
in 40 CFR part 178. To ensure

[[Page 47446]]

proper receipt by EPA, you must identify docket ID number EPA-HQ-OPP-
2009-0002 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 November 16, 
2009.
    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-2009-0002, by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     Mail: Office of Pesticide Programs (OPP) Regulatory Public 
Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460-0001.
     Delivery: OPP Regulatory Public Docket (7502P), 
Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South 
Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only 
accepted during the Docket Facility's normal hours of operation (8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays). 
Special arrangements should be made for deliveries of boxed 
information. The Docket Facility telephone number is (703) 305-5805.

II. Petition for Tolerance

    In the Federal Register of April 8, 2009 (74 FR 15971) (FRL-8407-
4), 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 
8F7443 and PP 8F7448) by Monsanto Company, 1300 I St., NW., Suite 450 
East, Washington DC 20052. The petitions requested that 40 CFR 180.470 
be amended by establishing tolerances for combined residues of the 
herbicide acetochlor, 2-chloro-2'-methyl-6'-ethyl-N-
ethoxymethylacetanilide, and its metabolites containing either the 2-
ethyl-6-methyl-aniline (EMA) or the 2-(1-hydroxyethyl)-6-methyl-aniline 
(HEMA) moiety, to be expressed as acetochlor equivalents, in or on 
cotton, gin byproducts; and cotton, undelinted seed at 4.0 parts per 
million (ppm) and 0.6 ppm, respectively (PP 8F7443); and soybean, seed 
at 1.0 ppm (PP 8F7448). That notice referenced a summary of the 
petition prepared by Monsanto Company, the registrant, which is 
available to the public in the docket, http://www.regulations.gov. 
There were no comments received in response to the notice of filing.
    Based upon review of the data supporting the petition, EPA has 
determined that a tolerance for residues of acetochlor and its 
metabolites is also required on soybean, meal at 1.2 ppm. EPA has also 
revised the tolerance expression for acetochlor to clarify the chemical 
moieties that are covered by the tolerances and specify how compliance 
with the tolerances is to be measured. The reasons for these changes 
are explained in Unit IV.C.

III. Aggregate Risk Assessment and Determination of Safety

    Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a 
tolerance (the legal limit for a pesticide chemical residue in or on a 
food) only if EPA determines that the tolerance is ``safe.'' Section 
408(b)(2)(A)(ii) of FFDCA defines ``safe'' to mean that ``there is a 
reasonable certainty that no harm will result from aggregate exposure 
to the pesticide chemical residue, including all anticipated dietary 
exposures and all other exposures for which there is reliable 
information.'' This includes exposure through drinking water and in 
residential settings, but does not include occupational exposure. 
Section 408(b)(2)(C) of FFDCA requires EPA to give special 
consideration to exposure of infants and children to the pesticide 
chemical residue in establishing a tolerance and to ``ensure that there 
is a reasonable certainty that no harm will result to infants and 
children from aggregate exposure to the pesticide chemical residue. . . 
.''
    Consistent with section 408(b)(2)(D) of FFDCA, and the factors 
specified in section 408(b)(2)(D) of FFDCA, EPA has reviewed the 
available scientific data and other relevant information in support of 
this action. EPA has sufficient data to assess the hazards of and to 
make a determination on aggregate exposure for the petitioned-for 
tolerances for residues of acetochlor, including its metabolites and 
degradates, on cotton, gin byproducts at 4.0 ppm; cotton, undelinted 
seed at 0.6 ppm; soybean, meal at 1.2 ppm; and soybean, seed at 1.0 
ppm. EPA's assessment of exposures and risks associated with 
establishing tolerances follows.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its 
validity, completeness, and reliability as well as the relationship of 
the results of the studies to human risk. EPA has also considered 
available information concerning the variability of the sensitivities 
of major identifiable subgroups of consumers, including infants and 
children.
    Acetochlor has low acute toxicity by the oral, dermal, and 
inhalation routes of exposure and is mildly irritating to the eyes. The 
results of two dermal irritation studies indicate that it is a mild to 
strong skin irritant. Acetochlor is also a strong dermal sensitizer.
    Evidence of neurotoxicity was observed in acute and subchronic 
neurotoxicity screening studies in rats, developmental toxicity studies 
in rats, and subchronic and chronic studies in dogs. In addition to the 
nervous system, the major target organs affected in subchronic and 
chronic studies in rats, dogs and mice exposed to acetochlor are the 
liver, thyroid (secondary to liver), kidney, testes, and erythrocytes. 
Species-specific target organs include the nasal olfactory epithelium 
in rats and the lungs in mice.
    There is no evidence of increased qualitative or quantitative 
susceptibility of fetuses or offspring to acetochlor exposure in the 
developmental and reproduction toxicity studies in rats and rabbits. In 
two developmental toxicity studies in rats, fetal effects (increased 
early resorptions, postimplantation loss, and decreased fetal weight) 
occurred at doses that also resulted in maternal toxicity (mortality, 
clinical signs of toxicity, and decreased maternal body weight gain). 
In two rabbit developmental toxicity studies there were no adverse 
fetal effects at the highest doses tested (HDT) (190 milligrams/
kilogram/day (mg/kg/day) and 300 mg/kg/day); whereas maternal toxicity 
(body weight loss) was seen at 50 mg/kg/day in one study. In three 
reproduction toxicity studies in rats, offspring effects (decreased pup 
weights in the first two studies; decreased pup weights, decreased F2 
litter size at birth, and focal hyperplasia and polypoid adenomata in 
nasal epithelium of adult F1 offspring at study termination in the 
third study) occurred at the same or higher doses than those resulting 
in parental toxicity (decreased body weight or weight gain in the first 
two studies; focal hyperplasia and polypoid adenomata in nasal 
epithelium of adult F1 offspring at study termination in the third 
study). There was no evidence of reproductive toxicity observed at any 
dose tested in two of the three reproductive toxicity studies in rats. 
The third reproduction study in rats showed a decreased number of 
implantations at the HDT of 1,750 ppm.

[[Page 47447]]

    There was evidence of carcinogenicity in studies conducted with 
acetochlor in rats and mice. A 23-month mouse carcinogenicity study 
showed weak evidence for increased benign lung tumors in females, and a 
78-week study showed weak evidence for increased benign lung tumors in 
males. The increases were considered equivocal, based on increases in 
benign tumors only, inconsistent dose-responses between the two 
studies, inconsistencies in the responses of males and females between 
the two studies, lack of pre-neoplastic lung lesions in the 23-month 
study (while the 78-week study showed an increase in bronchiolar 
hyperplasia), and the variable incidence of lung tumors known to occur 
in older mice.
    Two carcinogenicity studies in rats showed an increase in nasal 
epithelial tumors and thyroid follicular cell tumors. Thyroid tumor 
incidence was relatively low, and there was evidence that the tumors 
were due to disruption of thyroid-pituitary homeostasis. There are 
acceptable mode of action data for the rat tumors (nasal olfactory 
epithelial tumors and thyroid follicular cell tumors) which are 
adequate to support a non-linear, margin of exposure (MOE), approach 
for assessment of cancer risk. The data show that, like the related 
compounds, alachlor and butachlor, tumor formation is dependent upon 
local cytotoxicity secondary to oxidative damage by a reactive quinone 
imine intermediate. The mechanistic data on nasal tumorigenesis of 
acetochlor in the rat, when considered together with the mutagenicity 
data on acetochlor and consistent findings in mechanistic and 
mutagenicity studies on the closely related compound alachlor, are 
considered adequate to demonstrate a cytotoxic, non-mutagenic mode of 
tumor induction.
    Because a clear mode of action was demonstrated for the rat tumors, 
EPA based the cancer classification on the data from the mouse. Given 
the weakness of these data (benign lung tumors in male and female mice 
and histiocytic sarcomas in female mice), EPA has classified acetochlor 
as having ``Suggestive Evidence of Carcinogenic Potential'' and 
determined that linear quantification of carcinogenic potential would 
not be appropriate for the mouse tumors. The rat nasal tumors, with a 
point of departure (POD) of 10 mg/kg/day, are the most sensitive effect 
for cancer risk. The chronic population adjusted dose (cPAD), based on 
the no-observed-adverse-effect level (NOAEL) of 2.0 mg/kg/day from the 
chronic dog study, will be protective of both non-cancer and cancer 
effects, including rat nasal tumors, thyroid tumors, and mouse tumors.
    Specific information on the studies received and the nature of the 
adverse effects caused by acetochlor as well as the NOAEL and the 
lowest-observed-adverse-effect level (LOAEL) from the toxicity studies 
can be found at http://www.regulations.gov in the document Acetochlor 
Human Health Risk Assessment for Proposed New Use of Acetochlor on 
Cotton and Soybeans, page 41 in docket ID number EPA-HQ-OPP-2009-0002.

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no 
appreciable risk, a toxicological POD is identified as the basis for 
derivation of reference values for risk assessment. The POD may be 
defined as the highest dose at which no adverse effects are observed 
(the NOAEL) in the toxicology study identified as appropriate for use 
in risk assessment. However, if a NOAEL cannot be determined, the 
lowest dose at which adverse effects of concern are identified (the 
LOAEL) or a Benchmark Dose (BMD) approach is sometimes used for risk 
assessment. Uncertainty/safety factors (UFs) are used in conjunction 
with the POD to take into account uncertainties inherent in the 
extrapolation from laboratory animal data to humans and in the 
variations in sensitivity among members of the human population as well 
as other unknowns. Safety is assessed for acute and chronic dietary 
risks by comparing aggregate food and water exposure to the pesticide 
to the acute population adjusted dose (aPAD) and cPAD. The aPAD and 
cPAD are calculated by dividing the POD by all applicable UFs. 
Aggregate short-term, intermediate-term, and chronic-term risks are 
evaluated by comparing food, water, and residential exposure to the POD 
to ensure that the MOE called for by the product of all applicable UFs 
is not exceeded. This latter value is referred to as the level of 
concern (LOC).
    For non-threshold risks, the Agency assumes that any amount of 
exposure will lead to some degree of risk. Thus, the Agency estimates 
risk in terms of the probability of an occurrence of the adverse effect 
greater than that expected in a lifetime. For more information on the 
general principles EPA uses in risk characterization and a complete 
description of the risk assessment process, see http://www.epa.gov/
pesticides/factsheets/riskassess.htm.
    A summary of the toxicological endpoints for acetochlor used for 
human risk assessment can be found at http://www.regulations.gov in the 
document Acetochlor Human Health Risk Assessment for Proposed New Use 
of Acetochlor on Cotton and Soybeans page 25 in docket ID number EPA-
HQ-OPP-2009-0002.

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 U.S. Department of Agriculture (USDA) 1994-1996 
and 1998 Nationwide Continuing Surveys of Food Intakes by Individuals 
(CSFII). As to residue levels in food, EPA assumed that residues are 
present in all commodities at the tolerance level and that 100% of 
commodities are treated with acetochlor. Dietary Exposure Evaluation 
Model 7.81 (DEEM\TM\ 7.81) default concentration factors were used to 
estimate residues of acetochlor in 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 CSFII. As to residue levels in food, EPA assumed that residues 
are present in soybeans and cotton at the tolerance level and that 100% 
of cotton and soybeans are treated with acetochlor. For existing uses 
of acetochlor, EPA assumed average field trial levels and 100 percent 
crop treated (PCT). DEEM\TM\ 7.81 default concentration factors were 
used to estimate residues of acetochlor in processed commodities.
    iii. Cancer. Based on the results of carcinogenicity studies in 
rats and mice, EPA classified acetochlor as having ``Suggestive 
Evidence of Carcinogenic Potential'' but determined that the chronic 
risk assessment will be protective of both non-cancer and cancer 
effects. Therefore, a separate exposure assessment to evaluate cancer 
risk is unnecessary.
    iv. Anticipated residue and PCT information. EPA used anticipated 
residues derived from the results of field trials in the chronic 
dietary exposure assessment. EPA did not use PCT

[[Page 47448]]

information in the acute or chronic exposure assessments.
    Section 408(b)(2)(E) of FFDCA authorizes EPA to use available data 
and information on the anticipated residue levels of pesticide residues 
in food and the actual levels of pesticide residues that have been 
measured in food. If EPA relies on such information, EPA must require 
pursuant to FFDCA section 408(f)(1) that data be provided 5 years after 
the tolerance is established, modified, or left in effect, 
demonstrating that the levels in food are not above the levels 
anticipated. For the present action, EPA will issue such Data Call-Ins 
as are required by FFDCA section 408(b)(2)(E) and authorized under 
FFDCA section 408(f)(1). Data will be required to be submitted no later 
than 5 years from the date of issuance of these tolerances.
    2. Dietary exposure from drinking water. The Agency used screening 
level water exposure models in the dietary exposure analysis and risk 
assessment for acetochlor in drinking water. These simulation models 
take into account data on the physical, chemical, and fate/transport 
characteristics of acetochlor. Further information regarding EPA 
drinking water models used in pesticide exposure assessment can be 
found at http://www.epa.gov/oppefed1/models/water/index.htm.
    Based on the Pesticide Root Zone Model/Exposure Analysis Modeling 
System (PRZM/EXAMS), the estimated drinking water concentration (EDWC) 
of acetochlor for acute exposures is estimated to be 75 parts per 
billion (ppb) for surface water. The EDWC for chronic exposures for 
non-cancer assessments is estimated to be 4.8 ppb for surface water. 
Residues of parent acetochlor in ground water are expected to be 
insignificant compared to residues in surface water.
    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure model. For acute dietary risk 
assessment, the water concentration value of 75 ppb was used to assess 
the contribution to drinking water. For chronic dietary risk 
assessment, the water concentration of value 9.5 ppb was used to assess 
the contribution to drinking water. This value is higher than the 
modeled EDWC for chronic exposures (4.8 ppm) and was derived from 
preliminary modeling that was subsequently refined. Since chronic 
exposure estimates using the higher value are below EPA's LOC, EPA did 
not revise the dietary exposure assessment to reflect the final modeled 
EDWC.
    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 any specific use patterns that would result in 
residential exposure.
    4. Cumulative effects from substances with a common mechanism of 
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when 
considering whether to establish, modify, or revoke a tolerance, the 
Agency consider ``available information'' concerning the cumulative 
effects of a particular pesticide's residues and ``other substances 
that have a common mechanism of toxicity.''
    The chloroacetanilides have been evaluated by the Agency and the 
FIFRA Scientific Advisory Panel (SAP) as a related group of chemicals 
for this purpose. Acetochlor is included in a Cumulative Assessment 
Group (CAG) of Chloroacetanilide pesticides. Structurally related 
chloroacetanilides include acetochlor, alachlor, butachlor, propachlor 
and metolachlor. For purposes of a cumulative risk assessment, it was 
determined that the common mechanism of toxicity group consists of 
alachlor, acetochlor and butachlor. Butachlor is excluded from the 
group for risk assessment purposes at present since there are no 
registered uses or tolerances for this chemical in the United States. 
The group was selected based on common endpoints of:
    i. Nasal turbinate tumors in rats, and a known mechanism of 
toxicity for development of these tumors.
    ii. Induction of hepatic UDP-Glucuronosyl Transferase (UDPGT), 
which results in increased incidence of thyroid follicular cell tumors 
secondary to disruption of pituitary-thyroid homeostasis. Thyroid 
effects were not included in the final cumulative assessment of the 
chloroacetanilide herbicides because they were determined to occur at 
excessively toxic dose levels, and therefore were not considered 
relevant to human risk assessment. Nasal tumors represent the most 
sensitive endpoint for both compounds.
    An updated cumulative risk assessment of the Chloroacetanilide CAG 
pesticides, acetochlor and alachlor, was conducted in April 2007. The 
risk assessment ``ACETOCHLOR/ALACHLOR: Revised Cumulative Risk 
Assessment for the Chloroacetanilides to Support the Proposed New Uses 
on Alachlor and Acetochlor''. PP 8F05000 and 8F5025 (Alachlor), PP 
6F4791, 1F6263 and 5F6918 (Acetochlor) is available in the docket 
established for this action (EPA-HQ-OPP-2009-0002). Based on the most 
recent Chloroacetanilide CAG cumulative risk assessment, cumulative 
risk is not of concern. A revised quantitative cumulative assessment 
was not conducted for the current assessment of proposed new uses for 
acetochlor, because the proposed new uses on cotton and soybeans would 
not affect the cumulative risk results. Acetochlor is a very minor 
contributor to cumulative risk when compared to alachlor, and the 
proposed new uses (cotton and soybeans) are minor contributors to 
acetochlor dietary risk.
    For information regarding EPA's efforts to determine which 
chemicals have a common mechanism of toxicity and to evaluate the 
cumulative effects of such chemicals, see EPA's website at http://
www.epa.gov/pesticides/cumulative.

D. Safety Factor for Infants and Children

    1. In general. Section 408(b)(2)(C) of FFDCA provides that EPA 
shall apply an additional tenfold (10X) margin of safety for infants 
and children in the case of threshold effects to account for prenatal 
and postnatal toxicity and the completeness of the database on toxicity 
and exposure unless EPA determines based on reliable data that a 
different margin of safety will be safe for infants and children. This 
additional margin of safety is commonly referred to as the FQPA safety 
factor (SF). In applying this provision, EPA either retains the default 
value of 10X, or uses a different additional SF when reliable data 
available to EPA support the choice of a different factor.
    2. Prenatal and postnatal sensitivity. The prenatal and postnatal 
toxicity database for acetochlor includes two rat and two rabbit 
developmental toxicity studies and three reproduction toxicity studies 
in rats. As discussed in Unit III.A., there was no evidence of 
qualitative or quantitative susceptibility of fetuses or offspring to 
acetochlor exposure in any of these studies.
    3. Conclusion. EPA has determined that the FQPA safety factor of 
10X must be retained as a database UF for acetochlor acute risk 
assessment. This decision is based on the following findings:
    i. The toxicity database for acetochlor is incomplete. Additional 
data pertaining to acetochlor's potential to cause developmental 
neurotoxicity (DNT) or immunotoxicity are outstanding.
    ii. Evidence of neurotoxicity was observed in acute and subchronic 
neurotoxicity screening studies in rats,

[[Page 47449]]

developmental toxicity studies in rats, and subchronic and chronic 
studies in dogs. Frank neuropathology was seen in a chronic study in 
the dog. EPA has required a DNT study in rats to assess susceptibility 
of offspring to neurotoxic effects relative to adult animals. Results 
of the DNT study could impact the current dose selected for assessing 
acute oral exposure, since the NOAEL used for acute dietary risk 
assessment (150 mg/kg/day) is greater than the NOAEL from a 
reproductive toxicity study (21 mg/kg/day) for acetochlor, and the DNT 
study will likely be conducted at dose levels similar to those of the 
reproductive toxicity study. The results of the DNT study are not 
expected to impact the dose selected for chronic risk assessment, which 
is based on the lower NOAEL of 2.0 mg/kg/day from the chronic dog 
study.
    iii. In accordance with 40 CFR part 158 Toxicology Data 
requirements, an immunotoxicity study (870.7800) is required for 
acetochlor. In the absence of specific immunotoxicity studies, EPA has 
evaluated the available acetochlor toxicity data to determine whether 
an additional database UF is needed to account for potential 
immunotoxicity. There are no indications in the available studies that 
organs associated with immune function, such as the thymus and spleen, 
are affected by acetochlor, and acetochlor does not belong to a class 
of chemicals (e.g., the organotins, heavy metals, or halogenated 
aromatic hydrocarbons) that would be expected to be immunotoxic.
    iv. There is no evidence that acetochlor results in increased 
susceptibility in in utero rats or rabbits in the prenatal 
developmental studies or in offspring in the 2-generation reproduction 
studies.
    v. There are no residual uncertainties identified in the exposure 
databases. The dietary food exposure assessments were performed based 
on 100% crop treated and tolerance-level residues or average residue 
levels derived from reliable field trials. EPA made conservative 
(protective) assumptions in the ground and surface water modeling used 
to assess exposure to acetochlor in drinking water. Residential 
exposure to acetochlor is not expected. These assessments will not 
underestimate the exposure and risks posed by acetochlor.
    After weighing this evidence, EPA retains significant uncertainty 
regarding potential neurotoxic effects in infants and children but does 
not have such concerns for immunotoxicity. Given the findings of 
neurotoxicity and the uncertainty regarding the sensitivity of fetal 
and neonatal animals to neurotoxic effects, EPA has concluded that it 
lacks reliable data to remove the FQPA 10X safety factor for acute 
exposures. For chronic exposures, EPA concludes that reliable data show 
that removal of the FQPA 10X factor will be safe for infants and 
children. Three factors predominate here. First, given the expected 
dosing in the DNT study, that study is unlikely to affect the cPAD, 
even if effects were seen at the lowest dose tested. Second, there is 
no evidence of increased susceptibility in multiple studies in multiple 
species. Third, although neurotoxic effects have been observed in the 
database, at lower doses the more significant effects are not related 
to neurotoxicity.

E. Aggregate Risks and Determination of Safety

    EPA determines whether acute and chronic pesticide exposures are 
safe by comparing aggregate exposure estimates to the aPAD and cPAD. 
The aPAD and cPAD represent the highest safe exposures, taking into 
account all appropriate SFs. EPA calculates the aPAD and cPAD by 
dividing the POD by all applicable UFs. For linear cancer risks, EPA 
calculates the probability of additional cancer cases given the 
estimated aggregate exposure. Short-term, intermediate-term, and 
chronic-term risks are evaluated by comparing the estimated aggregate 
food, water, and residential exposure to the POD to ensure that the MOE 
called for by the product of all applicable UFs is not exceeded.
    1. Acute risk. An acute aggregate risk assessment takes into 
account exposure estimates from acute dietary consumption of food and 
drinking water. Using the exposure assumptions discussed in this unit 
for acute exposure, the acute dietary exposure from food and water to 
acetochlor will occupy 11% of the aPAD for infants less than 1 year 
old, the population group receiving the greatest exposure.
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that chronic exposure to 
acetochlor from food and water will utilize 6% of the cPAD for infants 
less than 1 year old, the population group receiving the greatest 
exposure. There are no residential uses for acetochlor.
    3. Short-term/intermediate-term risk. Short-term and intermediate-
term aggregate exposure take into account short-term or intermediate-
term residential exposure plus chronic exposure from food and water 
(considered to be a background exposure level). Acetochlor is not 
registered for any use patterns that would result in residential 
exposure. Therefore, the short-term or intermediate-term aggregate risk 
is the sum of the risk from exposure to acetochlor through food and 
water and will not be greater than the chronic aggregate risk.
    4. Aggregate cancer risk for U.S. population. As explained in Unit 
III.A., risk assessments based on the endpoint selected for chronic 
risk assessment are considered to be protective of any potential 
carcinogenic risk from exposure to acetochlor. Based on the results of 
the chronic risk assessment discussed above in Unit E.2., EPA concludes 
that acetochlor is not expected to pose a cancer risk.
    5. 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

    Adequate enforcement methodology (high performance liquid 
chromatography (HPLC) method with oxidative coulometric electrochemical 
detection (OCED)) is available to enforce the tolerance expression. The 
method may be requested from: Chief, Analytical Chemistry Branch, 
Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD 20755-5350; 
telephone number: (410) 305-2905; e-mail address: 
residuemethods@epa.gov.

B. International Residue Limits

    There are no CODEX, Canadian or Mexican maximum residue limits 
established for residues of acetochlor on cotton or soybean 
commodities.

C. Revisions to Petitioned-For Tolerances

    The registrant proposed a tolerance for residues of acetochlor and 
its metabolites on soybean, seed at 1.0 ppm. Based on processing data 
for soybean showing the potential for residues of acetochlor to 
concentrate in soybean meal (1.2X), EPA determined that a tolerance is 
also needed for soybean, meal at 1.2 ppm.
    Tolerances for acetochlor are currently expressed in terms of 
``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.'' EPA is revising the tolerance expression

[[Page 47450]]

for existing tolerances and the new tolerances on cotton and soybeans 
to clarify the chemical moieties that are covered by the tolerances and 
specify how compliance with the tolerances is to be measured. The 
revised tolerance expression makes clear that the tolerance covers 
``residues of acetochlor, including its metabolites and degradates,'' 
and that compliance with the tolerance levels will be determined by 
measuring only ``acetochlor, 2-chloro-2'-methyl-6-ethyl-N-
ethoxymethylacetanilide, and its metabolites containing the EMA moiety 
and the HEMA moiety. Both parent and the named metabolites shall be 
determined as EMA and HEMA, and calculated as the stoichiometric 
equivalents of acetochlor.''
    EPA has determined that it is reasonable to make this change final 
without prior proposal and opportunity for comment, because public 
comment is not necessary, in that the change has no substantive effect 
on the tolerance, but rather is merely intended to clarify the existing 
tolerance expression.

V. Conclusion

    Therefore, tolerances are established for residues of acetochlor, 
including its metabolites and degradates, on cotton, gin byproducts at 
4.0 ppm; cotton, undelinted seed at 0.6 ppm; soybean, meal at 1.2 ppm; 
and soybean, seed at 1.0 ppm. Compliance with these tolerance levels is 
to be determined by measuring only acetochlor, 2-chloro-2'-methyl-6-
ethyl-N-ethoxymethylacetanilide, and its metabolites containing the EMA 
moiety and the HEMA moiety. Both parent and the named metabolites shall 
be determined as EMA and HEMA, and calculated as the stoichiometric 
equivalents of acetochlor.

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances under section 408(d) of 
FFDCA in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled Regulatory Planning and 
Review (58 FR 51735, October 4, 1993). Because this final rule has been 
exempted from review under Executive Order 12866, this final rule is 
not subject to Executive Order 13211, entitled Actions Concerning 
Regulations That Significantly Affect Energy Supply, Distribution, or 
Use (66 FR 28355, May 22, 2001) or Executive Order 13045, entitled 
Protection of Children from Environmental Health Risks and Safety Risks 
(62 FR 19885, April 23, 1997). This final rule does not contain any 
information collections subject to OMB approval under the Paperwork 
Reduction Act (PRA), 44 U.S.C. 3501 et seq., nor does it require any 
special considerations under Executive Order 12898, entitled Federal 
Actions to Address Environmental Justice in Minority Populations and 
Low-Income Populations (59 FR 7629, February 16, 1994).
    Since tolerances and exemptions that are established on the basis 
of a petition under section 408(d) of FFDCA, such as the tolerance in 
this final rule, do not require the issuance of a proposed rule, the 
requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et 
seq.) do not apply.
    This final rule directly regulates growers, food processors, food 
handlers, and food retailers, not States or tribes, nor does this 
action alter the relationships or distribution of power and 
responsibilities established by Congress in the preemption provisions 
of section 408(n)(4) of FFDCA. As such, the Agency has determined that 
this action will not have a substantial direct effect on States or 
tribal governments, on the relationship between the national government 
and the States or tribal governments, or on the distribution of power 
and responsibilities among the various levels of government or between 
the Federal Government and Indian tribes. Thus, the Agency has 
determined that Executive Order 13132, entitled Federalism (64 FR 
43255, August 10, 1999) and Executive Order 13175, entitled 
Consultation and Coordination with Indian Tribal Governments (65 FR 
67249, November 9, 2000) do not apply to this final rule. In addition, 
this final rule does not impose any enforceable duty or contain any 
unfunded mandate as described under Title II of the Unfunded Mandates 
Reform Act of 1995 (UMRA) (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: August 31, 2009.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

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

PART 180--[AMENDED]

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

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

0
2. Section 180.470 is amended by revising the introductory text in 
paragraphs (a) and (d); alphabetically adding the entries cotton, gin 
byproducts; cotton, undelinted seed; soybean, meal; and soybean, seed 
to the table in paragraph (a), and by removing the entry for ``soybean, 
seed'' from the table in paragraph (d) to read as follows.

Sec.  180.470  Acetochlor; tolerances for residues.

    (a) General. Tolerances are established for residues of acetochlor, 
including its metabolites and degradates, in or on the commodities in 
the table below. Compliance with the tolerance levels specified below 
is to be determined by measuring only 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. Both parent and the named metabolites shall be 
determined as ethyl methyl aniline (EMA) and hydroxyethyl methyl 
aniline (HEMA), and calculated as the stoichiometric equivalents of 
acetochlor, in or on the following commodities:

[[Page 47451]]

----------------------------------------------------------------------------------------------------------------
                            Commodity                                            Parts per million
----------------------------------------------------------------------------------------------------------------
                                                    * * * * *
Cotton, gin byproducts...........................................                                            4.0
Cotton, undelinted seed..........................................                                            0.6
                                                    * * * * *
Soybean, meal....................................................                                            1.2
Soybean, seed....................................................                                            1.0
----------------------------------------------------------------------------------------------------------------

* * * * *
    (d) Indirect or inadvertent residues. Tolerances are established 
for indirect or inadvertent residues of acetochlor, including its 
metabolites and degradates, in or on the raw agricultural commodities 
in the table to this paragraph when present therein as a result of 
application of acetochlor to the growing crops in the table to 
paragraph (a) of this section. Compliance with the tolerance levels 
specified below is to be determined by measuring only 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. Both parent and the named metabolites 
shall be determined as ethyl methyl aniline (EMA) and hydroxyethyl 
methyl aniline (HEMA), and calculated as the stoichiometric equivalents 
of acetochlor, in or on the following commodities.
* * * * *
[FR Doc. E9-21845 Filed 9-15-09; 8:45 am]

BILLING CODE 6560-50-S