Document ID: EPA-HQ-OPP-2006-0292-0003
Agency: epa
Document Type: Rule
Title: S-metolachlor; Pesticide Tolerance
Posted Date: 2006-08-30T12:47:11Z

[Federal Register: August 30, 2006 (Volume 71, Number 168)]
[Rules and Regulations]               
[Page 51505-51510]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30au06-19]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2006-0292; FRL-8090-2]

 
S-metolachlor; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for combined residues 
of S-metolachlor in or on pumpkin, and squash, winter. Interregional 
Research Project Number 4 (IR-4) requested these tolerances 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 August 30, 2006. Objections and 
requests for hearings must be received on or before October 30, 2006, 
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-2006-0292. 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: Shaja R. Brothers, Registration 
Division (7505P), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001; telephone number: (703) 308-3194; e-mail address: 
brothers.shaja@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.
 To access the OPPTS Harmonized Guidelines 

referenced in this document, go directly to the guidelines at http://www.epa.gpo/opptsfrs/home/guidelin.htm

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-2006-0292 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 October 30, 2006.
    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

[[Page 51506]]

EPA-HQ-OPP-2006-0292, 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 
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 21, 2006 71 FR 20663 FRL-8064-6, 
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 5E7015) 
by IR-4, 681 Highway 1 South, North Brunswick, NJ 08902-3390. The 
petition requested that 40 CFR 180.368(a)(3) be amended by establishing 
tolerances for combined residues of the herbicide S-metolachlor, S-2-
chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-
methylethyl)acetamide], its R-enantiomer, and its metabolites, 
determined as the derivatives, 2-[2-ethyl-6-methylphenyl)amino]-1-
propanol and 4-(2-ethyl-6-methylphenyl)-2-hydroxy-5-methyl-3-
morpholinone, in or on pumpkin and squash, winter at 1.0 part per 
million (ppm), respectively. The tolerances were subsequently amended 
to 0.1 ppm for raw agricultural commodities previously mentioned. This 
notice included a summary of the petition prepared by Syngenta, the 
registrant. There were no comments received in response to the notice 
of filing.
    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 S-
metolachlor on pumpkin at 0.1 ppm, and squash, winter at 0.1 ppm. EPA's 
assessment of exposure and risk associated with establishing the 
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 metolachlor and S-metolachlor 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 (Docket No. EPA-HQ-OPP- 2006-0292-0003; pages 53-

64).

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no 
appreciable risk, the dose at which no adverse effects are observed 
(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 lowest dose at which adverse effects of 
concern are identified (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 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 metolachlor and S-
metolachlor used for human risk assessment is discussed at 
http://www.regulations.gov (Docket No. EPA-HQ-OPP-2006-0292; pages 20-21).

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. Tolerances have been 
established (40 CFR 180.368) for the combined residues of S-
metolachlor, in or on a variety of raw agricultural commodities. Meat, 
milk, poultry and egg tolerances have also been established. Risk 
assessments were conducted by EPA to assess dietary exposures from S-
metolachlor in food as follows:
    Both the acute and chronic analyses assume tolerance-level residues 
on all crops with established, pending, or proposed tolerances for 
metolachlor and/or S-metolachlor. In cases where separate tolerance 
listings occur for both metolachlor and S-metolachlor on the same 
commodity, the higher value of the two is used in the analyses.
    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.
     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 USDA 1994-1996 and 1998 
Nationwide Continuing Surveys of Food Intake by Individuals (CSFII), 
and accumulated

[[Page 51507]]

exposure to the chemical for each commodity. The following assumptions 
were made for the acute exposure assessments: An acute dietary analysis 
for S-metolachlor was conducted using tolerance level residues and 100 
% crop treated (CT) for all existing 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 chronic dietary analysis for S-metolachlor was conducted 
using tolerance level residues and 100 %CT data for all existing and 
proposed uses.
    iii. Cancer. Metolachlor has been classified as a Group C, possible 
human carcinogen based on liver tumors in rats at the highest dose 
tested (HDT). The chronic NOAEL of 15 mg/kg/day that was established 
based on tumors in the rat (seen at the HDT of 150 mg/kg/day) is 
comparable to the NOAEL of 9.7 mg/kg/day selected for establishing the 
chronic reference dose for metolachlor. EPA has concluded that the 
chronic dietary PAD is protective for cancer dietary risk. Therefore, a 
separate cancer aggregate risk assessment was not conducted.
    2. Dietary exposure from drinking water. The Agency lacks 
sufficient monitoring exposure data to complete a comprehensive dietary 
exposure analysis and risk assessment for s-metolachlor 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 s-metolachor. 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.

     A drinking water assessment was conducted based on monitoring data 
from several sources, as well as on Tier 1 FIRST and SCI-GROW modeling 
results. This assessment is a worst-case scenario and demonstrates high 
end numbers. The analytical methods used to obtain the monitoring data 
are not able to distinguish between metolachlor and S-metolachlor; 
therefore, the estimated environmental concentrations (EECs) presented 
in this risk assessment are representative of both racemic metolachlor 
and S-metolachlor.
    EECs for metolachlor and S-metolachlor were calculated for both the 
parent compound and the ethanesulfonic acid (ESA) and oxanilic acid 
(OA) degradates. Although it was determined by the EPA that the ESA and 
OA metabolites appear to be less toxic than parent metolachlor, they 
are included in the risk assessment since they were found in greater 
abundance than the parent in water monitoring studies.
    The crops with the highest maximum seasonal application rates are 
turf (S-metolachlor only) and corn (racemic metolachlor and S-
metolachlor) with a maximum seasonal application rate of 4.0 lbs ai/A. 
Based on PRZM/EXAMS modeling the maximum peak and annual average 
concentrations of metolachlor/ S-metolachlor in surface water were 199 
ug/l and 9.2 ug/l, respectively. Based on FIRST modeling results, the 
estimate of the drinking water concentration from surface water sources 
of metolachlor ESA, a major degradate of metolachlor, is not likely to 
exceed 31.9 ug/L for the annual peak concentration and 22.8 ug/L for 
the annual average exposure for use on turf/corn at a maximum annual 
application rate of 4.0 lbs ai/A. Based on FIRST modeling results, the 
estimate of the drinking water concentration from surface water sources 
of metolachlor OA, another major degradate of metolachlor, is not 
likely to exceed 91.4 ug/L for the annual peak concentration and 65.1 
ug/L for the annual average exposure for use on turf/corn at a maximum 
annual application rate of 4.0 lbs ai/A (ground application with no 
spray drift).
    The SCI-GROW screening model was used to estimate groundwater 
concentrations. The estimated concentration of metolachlor/ S-
metolachlor in drinking water from shallow groundwater sources is 5.5 
ug/l for application on corn at a seasonal maximum rate of 4.0 lbs ai/
A. This concentration is appropriate for both the peak and annual 
average exposures. The EEC for metolachlor degradate ESA based on 
metolachlor use on turf/corn is not expected to exceed 65.8 ug/l for 
peak and annual average exposures. The EEC for metolachlor OA from 
metolachlor use on turf/corn is not expected to exceed 31.7 ug/l for 
peak and annual average exposures.

                                           Table 1: Metolachlor EEC's
----------------------------------------------------------------------------------------------------------------
                                         Surface Water (peak)   Surface Water (average)        Ground Water
----------------------------------------------------------------------------------------------------------------
Parent                                                     199                      9.2                      5.5
----------------------------------------------------------------------------------------------------------------
metolachlor ESA                                           31.9                     22.8                     65.8
----------------------------------------------------------------------------------------------------------------
metolachlor OA                                            91.4                     65.1                     31.7
----------------------------------------------------------------------------------------------------------------
Total EECs (ppb)                                         322.3                     97.1                    103.0
----------------------------------------------------------------------------------------------------------------

    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure model (DEEM-FCID\TM\). For acute 
dietary risk, since the surface water EDWCs are higher than the 
groundwater EDWC, the peak concentration of 322.3 ppb was used to 
access the contribution to drinking water. For chronic dietary risk 
assessment, since the ground water EDWCs are higher than the surface 
water EDWC the ground water concentration of 103.0 ppb was used to 
access the contribution to drinking water.
    3. From non-dietary exposure. The term ``residential exposure'' is 
used in this document to refer to non-occupational, non-dietary 
exposure (e.g., for lawn and garden pest control, indoor pest control, 
termiticides, and flea and tick control on pets).
    The formulated S-metolachlor end-use product is labeled under the 
trade name Pennant MAGNUM\TM\ (EPA Reg. No. 100-950) to distinguish the 
new product from the original metolachlor formulation named Pennant\TM\ 
(EPA Reg. No. 100-691). Pennant MAGNUM\TM\ (7.62 lbs. active ingredient 
per gallon) is labeled for use on commercial (sod farm) and residential 
warm-season turfgrasses and other

[[Page 51508]]

noncrop land including golf courses, sports fields, and ornamental 
gardens. Although not labeled as a restricted-use pesticide, Pennant 
MAGNUM\TM\, as currently marketed, is not intended for homeowner 
purchase or use (intended for use by professionals). On this basis, 
with regard to the requirements of FQPA, metolachlor and S-metolachlor 
are assessed only for post application exposure and risk. Pennant 
MAGNUM\TM\ and Pennant\TM\ are both emulsifiable concentrates (EC).
    For this risk assessment, small children are the population group 
of concern. Although the type of site that S-metolachlor may be used on 
varies from golf courses to ornamental gardens, the scenario chosen for 
risk assessment (residential turf use) represents what the Agency 
considers the likely upper-end of possible exposure. Post application 
exposures from various activities following lawn treatment are 
considered to be the most common and significant in residential 
settings. Since toxicity was not observed in a dermal toxicity study, 
up to a dose level of 1,000 mg/kg/day, the only parameter of risk 
addressed in this assessment is the possible oral exposure of small 
children from treated turf, or soil.
    The estimate for hand-to-mouth exposure on the day of treatment is 
0.037 mg/kg/day (MOE = 1,400) for S-metolachlor and 0.06 mg/kg/day (MOE 
= 840) for metolachlor. (MOE estimates are based on the short-term 
NOAEL of 50 mg/kg/day).
    The estimate for object-to-mouth exposure on the day of treatment 
is 0.0092 mg/kg/day (MOE = 5,400) for S-metolachlor and 0.015 mg/kg/day 
(MOE = 3,300) for metolachlor. (MOE estimates are based on the short-
term NOAEL of 50 mg/kg/day).
    The estimate for soil ingestion exposure on the day of treatment is 
0.00012 mg/kg/day (MOE = 400,000) for S-metolachlor and 0.0002 mg/kg/
day (MOE = 250,000) for metolachlor. (MOE estimates are based on the 
short-term NOAEL of 50 mg/kg/day).
    The estimate for hand-to-mouth, object-to-mouth, and soil ingestion 
combined (on the day of treatment) is 0.046 mg/kg/day (MOE = 1,100) for 
S-metolachlor and 0.075 mg/kg/day (MOE = 670) for metolachlor. (MOE 
estimates are based on the short-term NOAEL of 50 mg/kg/day).
    The MOE estimates are greater than 100 and indicate that the 
potential metolachlor/S-metolachlor exposure (to children) associated 
with residential use is not of concern. Although considered an upper-
bound, the exposure estimate for the three scenarios, combined, is 
recommended for aggregate (residential, food, and drinking water) risk 
estimates.
    4. 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.''
    Unlike other pesticides for which EPA has followed a cumulative 
risk approach based on a common mechanism of toxicity, EPA has not made 
a common mechanism of toxicity finding as to S-metolachlor and any 
other substances and S-metolachlor does not appear to produce a toxic 
metabolite produced by other substances. For the purposes of this 
tolerance action, therefore, EPA has not assumed that S-metolachlor has 
a common mechanism of toxicity with other substances. 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 the policy statements released by EPA's Office of 
Pesticide Programs concerning common mechanism determinations and 
procedures for cumulating effects from substances found to have a 
common mechanism on EPA's website at http://www.epa.gov/pesticides/cumulative
.

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 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. 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--i. Metolachlor. The prenatal 
developmental studies in the rat and rabbit revealed no evidence of a 
qualitative or quantitative susceptibility in fetal animals. In the 
rabbit prenatal developmental toxicity study, at 360 mg/kg/day, 
maternal animals had persistent anorexia and decreased body weight 
gain; the NOAEL was 120 mg/kg/day. In the rat prenatal developmental 
toxicity study, frank toxicity [death, clinical signs (clonic and/or 
tonic convulsions, excessive salivation, urine-stained abdominal fur 
and/or excessive salivation) and decreased body weight gain] was 
observed at the limit dose of 1,000 mg/kg/day in maternal animals; the 
NOAEL was 300 mg/kg/day. The developmental effects at 1,000 mg/kg/day 
included slightly decreased number of implantations per dam, decreased 
number of live fetuses/dam, increased number of resorptions/dam and 
significant decrease in mean fetal body weight.
    In the two-generation reproduction study in rats, there was no 
evidence of parental or reproductive toxicity at approximately 80 mg/
kg/day, the HDT. At this dose, there was a minor decrease in fetal body 
weight beginning at lactation day 4; the NOAEL was approximately 25 mg/
kg/day. Since a similar body weight decrease was not seen on lactation 
day zero, the cause of the effect on later lactation days is most 
likely due to exposure of the pups to metolachlor in the diet and/or 
milk and therefore is not evidence of an increased quantitative 
susceptibility in post-natal animals.
    ii. S-metolachlor. There was no evidence of increased quantitative 
or qualitative fetal susceptibility in the prenatal developmental 
studies in rats and rabbits. In the rat, maternal toxicity [increased 
clinical signs of toxicity (pushing head through bedding) and decreased 
body weights/body weight gains, food consumption and food efficiency 
was observed at 500 mg/kg/day; the NOAEL was 50 mg/kg/day. There were 
no developmental effects at 1,000 mg/kg/day, the HDT. In the rabbit, 
clinical signs of toxicity (little/none/soft stool) were observed at 
100 mg/kg/day; the NOAEL was 20 mg/kg/day. No developmental effects 
were observed at 500 mg/kg/day, the HDT.
    3. Conclusion. There is a complete toxicity data base for S-
metolachlor and exposure data are complete or are estimated based on 
data that reasonably accounts for potential exposures. EPA determined 
that the 10X SF to protect infants and children should be reduced to 1X 
for the following reasons:
    i. The toxicology database is complete for the FQPA assessment.

[[Page 51509]]

    ii. There is no indication of quantitative or qualitative increased 
susceptibility of rats or rabbits to in utero and/or postnatal exposure 
to metolachlor or S-metolachlor in the available toxicity data.
    iii. A developmental neurotoxicity study is not required for 
metolachlor or S-metolachlor.
    iv. The dietary (food and drinking water) and non-dietary exposure 
(residential) assessments will not underestimate the potential 
exposures for infants and children from the use of metolachlor or S-
metolachlor.

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 S-metolachlor will occupy < 1% of the aPAD for the US population and 
other population subgroups, and 2% of the aPAD for all infants < 1 year 
old. 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 S-
metolachlor from food and water will utilize 4% of the cPAD for the 
U.S. population, 10% of the cPAD for all infants <  1 year old, and 8% 
of the cPAD for children 1-2 years old. 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). A short-term aggregate 
risk assessment considers potential exposure from food, drinking water, 
and short-term, non-occupational (residential) pathways of exposure for 
a duration of 1 to 30 days.
    Potential short-term, non-occupational risk scenarios for S-
metolachlor consist of oral exposure of children to treated lawns only. 
In this aggregate short-term risk assessment, exposure from food, 
drinking water, and residential lawns has been considered. The exposure 
to food and water has already been considered in the chronic dietary 
risk assessment. Since only children have the potential for non-
occupational, short-term risk, they are the only population subgroup 
for which an aggregate short-term risk assessment was conducted. 
Toddlers' S-metolachlor incidental oral exposure is assumed to include 
hand-to-mouth exposure, object-to-mouth exposure and exposure through 
incidental ingestion of soil.

                  Table 2.--Aggregate Risk Assessment for Short-Term Exposure to S-metolachlor
----------------------------------------------------------------------------------------------------------------
                                                                     Short-Term Scenario
                                            --------------------------------------------------------------------
                                                                         Average
                 Population                                              Food and   Residential   Aggregate MOE
                                             NOAEL mg/kg/    LOC\1\       Water     Exposure mg/   (food, water
                                                 day                   Exposure mg/  kg/day\2\         and
                                                                          kg/day                 residential)\3\
----------------------------------------------------------------------------------------------------------------
All infants < 1 yr old                                 50          100     0.010003        0.046            890
----------------------------------------------------------------------------------------------------------------
\1\ The level of concern (LOC) MOE is 100, based on inter- and intra-species safety factors totaling 100.
\2\ Residential Exposure = [Incidental Oral exposure from all possible sources-combined hand-to-mouth, object-to-
  mouth, and soil ingestion oral exposure]. No residential oral exposure is expected for adults
\3\ Aggregate MOE = [NOAEL / (Avg Food and Water Exposure + Residential Exposure)]

    4. Aggregate cancer risk for U.S. population. S-metolachlor is 
classified as classified as a Group C, possible human carcinogen. EPA 
has concluded that the chronic dietary PAD is protective for cancer 
dietary risk and, as noted above, chronic exposure is below the chronic 
dietary PAD.
    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, and to infants and children from aggregate 
exposure to S-metolachlor residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate methodology is available for enforcing the current and 
proposed tolerances. The Pesticide Analytical Manual (PAM, Vol. II) 
lists a GC/NPD method (Methods I) for determining residues in/on plants 
and a GC/MSD method (Method II) for determining residues in livestock 
commodities. These methods determine residues of S-metolachlor and its 
metabolites as either CGA-37913 or CGA-49751 following acid hydrolysis. 
A modified version of this method (Syngenta Method No. 1848-01) which 
uses liquid chromotography/mass spectrometry/mass spectrometry (LC/MS/
MS) has also been used. Adequate data are available on the recovery of 
metolachlor through Multi-residue Method Testing Protocols. The FDA 
PESTDATA database indicates that S-metolachlor is completely recovered 
through Method 302, PAM Vol. I.

B. International Residue Limits

    There are currently no Codex, Canadian or Mexican MRLs for S-
metolachlor; therefore there are no international harmonization issues 
for these actions.

V. Conclusion

    Therefore, the tolerances are established for combined residues of 
S-metolachlor, S-2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-
methylethyl)acetamide], its R-enantiomer, and its metabolites, 
determined as the derivatives, 2-[2-ethyl-6-methylphenyl)amino]-1-
propanol and 4-(2-ethyl-6-methylphenyl)-2-hydroxy-5-methyl-3-
morpholinone, in or on pumpkin and squash, winter at 0.1 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

[[Page 51510]]

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 (65 FR 67249, 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: August 23, 2006.
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 180.368 is amended in paragraph (a)(3) by adding commodities 
to the table to read as follows:

Sec.  180.368  Metolachlor; tolerances for residues.

    (a)* * *
    (3) * * *

------------------------------------------------------------------------
                   Commodity                        Parts per million
------------------------------------------------------------------------
                                * * * * *
Pumpkin                                                              0.1
                                * * * * *
Squash, winter                                                       0.1
                                * * * * *
------------------------------------------------------------------------

* * * * *

[FR Doc. E6-14443 Filed 8-29-06; 8:45 am]

BILLING CODE 6560-50-S