[Federal Register Volume 68, Number 188 (Monday, September 29, 2003)]
[Rules and Regulations]
[Pages 55858-55870]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-24562]


-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-2003-0315; FRL-7328-6]


Sethoxydim; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This regulation establishes a tolerance for combined residues 
of sethoxydim (2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-
hydroxy-2-cyclohexen-1-one) and its metabolites containing the 2-
cyclohexen-1-one moiety (calculated as the herbicide) in or on corn, 
sweet, forage; corn, sweet, stover; juneberry; lingonberry; pistachio; 
salal; and safflower and increases the tolerance on cattle, meat by 
products; corn, sweet, kernels plus cob with husk removed; goat, meat 
byproducts; hog, meat byproducts; horse, meat byproducts; milk; and 
sheep, meat byproducts. BASF Corporation requested the tolerances for 
corn, sweet, forage; corn, sweet, stover and the increase in tolerance 
for corn, sweet, kernels plus cob with husk removed; milk; and meat 
products under the Federal Food, Drug, and Cosmetic Act (FFDCA), as 
amended by the Food Quality Protection Act of 1996 (FQPA). 
Interregional Project 4 (IR-4) requested the tolerances on 
juneberry, lingonberry, pistachio, salal, and safflower 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 September 29, 2003. Objections and 
requests for hearings, identified by docket ID number OPP-2003-0315, 
must be received on or before November 28, 2003.

ADDRESSES: Written objections and hearing requests may be submitted 
electronically, by mail, or through hand delivery/courier. Follow the 
detailed instructions as provided in Unit VI. of the SUPPLEMENTARY 
INFORMATION.

FOR FURTHER INFORMATION CONTACT: Jim Tompkins, Registration Division 
(7505C), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 305-5697; e-mail address: [email protected].

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:
    [sbull] Crop Production (NAICS 111)
    [sbull] Animal Production (NAICS 112)
    [sbull] Food Manufacturing (NAICS 311)
    [sbull] Pesticide Manufacturing (NAICS 32532)
    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. To determine 
whether you or your business may be affected by

[[Page 55859]]

this action, you should carefully examine the applicability provisions 
in Unit II. 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 Get Copies of this Document and Other Related Information?

    1. Docket. EPA has established an official public docket for this 
action under docket identification (ID) number OPP-2003-0315. The 
official public docket consists of the documents specifically 
referenced in this action, any public comments received, and other 
information related to this action. Although a part of the official 
docket, the public docket does not include Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. The official public docket is the collection of materials 
that is available for public viewing at the Public Information and 
Records Integrity Branch (PIRIB), Rm. 119, Crystal Mall 2, 
1921 Jefferson Davis Hwy., Arlington, VA. This 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.
    2. Electronic access. You may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr/. A frequently updated 
electronic version of 40 CFR part 180 is available at http://www.access.gpo.gov/nara/cfr/cfrhtml_00/Title_40/40cfr180_00.html/, a 
beta site currently under development. To access the OPPTS Harmonized 
Guidelines referenced in this document, go directly to the guidelines 
at http://www.epa.gov/opptsfrs/home/guidelin.htm/.
    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public 
comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Although not all docket materials may be 
available electronically, you may still access any of the publicly 
available docket materials through the docket facility identified in 
Unit I.B.1. Once in the system, select ``search,'' then key in the 
appropriate docket ID number.

II. Background and Statutory Findings

    In the Federal Register of January 18, 2000 (65 FR 2612) (FRL-6486-
4), August 7, 2002 (67 FR 51267) (FRL-7191-3), and September 11, 2002 
(67 FR 57593) (FRL-7198-11), EPA issued a notice pursuant to section 
408 of FFDCA, 21 U.S.C. 346a, as amended by FQPA (Public Law 104-170), 
announcing the filing of pesticide petitions (9E6012, 9E6021, and 
0E6150) by the Interregional Research Project Number 4, Technology 
Centre and Rutgers State University of New Jersey, 681 U.S. Highway 
1 South, North Brunswick, NJ 08902-3390 and pesticide petition 
(2F4075) by BASF Corporation, P.O. Box 13528, Research Triangle Park, 
NC 27709-3528. These notices included summaries of the petitions 
prepared by BASF Corporation, the registrant. There were no comments 
received in response to these notices of filing.
    These petitions requested that 40 CFR part 180 be amended to 
establish tolerances for cyclohexen-1-one moiety (calculated as the 
herbicide), in or on corn, sweet, forage at 3.0 parts per million 
(ppm); corn, sweet, stover at 3.5 ppm; lingonberry at 5.0 ppm; 
juneberry at 5.0 ppm; pistachios at 0.2 ppm; safflower at 15.0 ppm and 
salal at 5.0 ppm, and increase the tolerance in cattle, meat byproducts 
from 0.2 ppm to 1.0 ppm; corn, sweet, kernels plus cob with husk 
removed from 0.2 ppm to 0.4 ppm; goat, meat byproducts from 0.2 ppm to 
1.0 ppm; horse, meat byproducts from 0.2 ppm to 1.0 ppm; milk from 0.05 
ppm to 0.5 ppm, and sheep, meat byproducts from 0.2 ppm to 1.0 ppm. The 
tolerance increases were a result of a 15-day reduction in the pre-
harvest interval for sweet corn requested by the registrant.
    Section 408(b)(2)(A)(i) of the 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 the 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 the 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 the final rule on 
Bifenthrin Pesticide Tolerances November 26, 1997 (62 FR 62961) (FRL-
5754-7).

III. Aggregate Risk Assessment and Determination of Safety

    Consistent with section 408(b)(2)(D) of the 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 the FFDCA, for a tolerance for combined residues of the 
herbicide sethoxydim, (2-[1-(ethoxyimino)butyl]-5-[2-
(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one) and its metabolites 
containing the 2-cyclohexen-1-one moiety (calculated as the herbicide), 
in or on corn, sweet, kernels plus cob with husk removed at 0.4 ppm; 
corn, sweet, forage at 3.0 ppm; corn, sweet, stover at 3.5 ppm; 
lingonberry at 5.0 ppm; juneberry at 5.0 ppm; milk at 0.5 ppm; cattle, 
meat byproducts at 1.0 ppm; goat, meat byproducts at 1.0 ppm; hog, meat 
byproducts at 1.0 ppm; horse, meat byproducts at 1.0 ppm and sheep meat 
byproducts at 1.0 ppm; pistachio at 0.2 ppm; safflower at 15.0 ppm and 
salal at 5.0 ppm. EPA's assessment of exposures and risks associated 
with establishing the tolerance 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. The natures of the toxic effects caused by sethoxydim are 
discussed in Table 1 of this unit as well as the no observed adverse 
effect level (NOAEL) and the lowest observed-adverse effect level 
(LOAEL) from the toxicity studies reviewed.

[[Page 55860]]



          Table 1.--Toxicology Profile for Sethoxydim Technical
------------------------------------------------------------------------
         Guideline No.               Study Type            Results
------------------------------------------------------------------------
870.1100                         Acute oral--rats   LD50 = male (M):
                                                     3,125 milligram/
                                                     kilogram (mg/kg);
                                                     female (F) 2,676 mg/
                                                     kg (category III)
------------------------------------------------------------------------
870.1200                         Acute dermal--     LD50 = > 5,000 mg/kg
                                  rats               (category III)
------------------------------------------------------------------------
870.1300                         Acute inhalation-- LC50 = M: 6.03 meter/
                                  rats               Liter (m/L); F 6.28
                                                     m/L (category III)
------------------------------------------------------------------------
870.2400                         Primary eye        No irritation
                                  irritation--rabb   (category IV)
                                  its
------------------------------------------------------------------------
870.2500                         Primary skin       No irritation
                                  irritation--rabb   (category IV)
                                  its
------------------------------------------------------------------------
870.2600                         Dermal             Waived based on lack
                                  sensitization--g   of sensitization in
                                  uinea pigs         guinea pigs with a
                                                     formulated product
------------------------------------------------------------------------
870.3100                         90-Day oral        Males
                                  toxicity rodents  NOAEL = 60.4
                                  (rats)            LOAEL = 196.3 mg/kg/
                                                     day
                                                    Females
                                                    NOAEL = 66.2
                                                    LOAEL = 200.5 mg/kg/
                                                     day Based on
                                                     decreases in body
                                                     weight, body weight
                                                     gain, and food
                                                     efficiency
------------------------------------------------------------------------
870.3100                         90-Day oral        Males
                                  toxicity rodents  NOAEL = 45.6
                                  (mice)            LOAEL = 137.1 mg/kg/
                                                     day
                                                    Females
                                                    NOAEL = 52.7
                                                    LOAEL = 164.4 mg/kg/
                                                     day based on
                                                     increased liver
                                                     weight and
                                                     histopathological
                                                     evidence of
                                                     hepatocellular
                                                     hypertrophy
------------------------------------------------------------------------
870.3150                         90-Day oral        Males and females
                                  toxicity          NOAEL not identified
                                  (nonrodents-      LOAEL = 3.4 mg/kg/
                                  dogs)              day (tentative)
                                                     based on possible
                                                     treatment-related
                                                     clinical findings
                                                     of cystitis of
                                                     urinary bladders
------------------------------------------------------------------------
870.3200                         21-Day dermal      Males and females
                                  toxicity          NOAEL = 1,000 mg/kg/
                                  (rabbits)          day higest dose
                                                     tested (HDT)
                                                    LOAEL not
                                                     established. No
                                                     localized or
                                                     systemic effects
------------------------------------------------------------------------
870.3465                         4-Week inhalation  Males and females
                                  toxicity (rats)   NOAEL = 0.3 mg/L (81
                                                     mg/kg/day)
                                                    LOAEL of 2.4 mg/L
                                                     (651 mg/kg/day),
                                                     based on increased
                                                     liver weight,
                                                     clinical chemistry
                                                     (increased total
                                                     serum bilirobin),
                                                     and liver
                                                     histopathology
------------------------------------------------------------------------
870.3700                         Prenatal           Maternal
                                  developmental     NOAEL = 180 mg/kg/
                                  toxicity (rats)    day
                                                    LOAEL = 650 mg/kg/
                                                     day (irregular
                                                     gaits, decreased
                                                     activity, excessive
                                                     salivation, and
                                                     anogenital
                                                     staining)
                                                    Developmental
                                                    NOAEL = 180 mg/kg/
                                                     day
                                                    LOAEL = 650 mg/kg/
                                                     day (21-22%
                                                     decrease in fetal
                                                     weights,
                                                     filamentous tail
                                                     and lack of tail
                                                     due to the absence
                                                     of sacral, and/or
                                                     caudal vertebrae,
                                                     and delayed
                                                     ossification in the
                                                     hyoids, vertebral
                                                     centrum, and/or
                                                     transverse
                                                     processes,
                                                     sternebrae and/or
                                                     metatarsals, and
                                                     pubes)
------------------------------------------------------------------------
870.3700                         Prenatal           Maternal
                                  developmental     NOAEL = 320 mg/kg/
                                  toxicity           day
                                  (rabbits)         LOAEL = 400 mg/kg/
                                                     day, (based on 37%
                                                     reduction in body
                                                     weight gain without
                                                     significant
                                                     differences in
                                                     group mean body
                                                     weights, and
                                                     decreased food
                                                     consumption during
                                                     dosing)
                                                    Developmental
                                                    NOAEL 320 mg/kg/day
                                                    LOAEL = 400 mg/kg/
                                                     day HDT based on an
                                                     increase in the
                                                     incidence of
                                                     incompletely
                                                     ossified 6th
                                                     sternebrae
------------------------------------------------------------------------

[[Page 55861]]

 
870.3800                         Reproduction and   Systemic
                                  fertility         NOAEL >=150 mg/kg/
                                  effects (rats)     day
                                                    LOAEL >150 mg/kg/day
                                                    Reproductive
                                                    NOAEL >=150 mg/kg/
                                                     day
                                                    LOAEL >150 mg/kg/day
                                                    Offspring
                                                    NOAEL = 30 mg/kg/day
                                                    LOAEL = 150 mg/kg/
                                                     day, based on
                                                     decreased body
                                                     weight in F2b pups
                                                     during lactation
                                                     and tail
                                                     abnormalities seen
                                                     in F1a and F1b
                                                     offspring
------------------------------------------------------------------------
870.4100                         Chronic toxicity   Males
                                  (dogs)            NOAEL = 17.5 mg/kg/
                                                     day
                                                    LOAEL = 110 mg/kg/
                                                     day
                                                    Females
                                                    NOAEL = 19.9 mg/kg/
                                                     day
                                                    LOAEL = 129 mg/kg/
                                                     day, based on
                                                     increase
                                                     hemosiderosis in
                                                     the spleen and
                                                     depressed myeloid
                                                     erythropoiesis in
                                                     the sternal bone
                                                     marrow, increased
                                                     absolute and
                                                     relative liver
                                                     weights, increased
                                                     alkaline
                                                     phosphatase and ALT
                                                     levels
------------------------------------------------------------------------
870.4200                         Carcinogenicity    Males
                                  (mice)            NOAEL = 13.8 mg/kg/
                                                     day
                                                    LOAEL = 41.2 mg/kg/
                                                     day, based on early
                                                     onset of liver
                                                     effects including
                                                     hepatocellular
                                                     hypertrophy and
                                                     fatty degeneration
                                                     in male mice. No
                                                     evidence of
                                                     carcinogenicity
------------------------------------------------------------------------
870.4300                         Combined chronic/  Male
                                  carcinogenicity   NOAEL = 12 mg/kg/day
                                  (rats)            LOAEL = 48 mg/kg/
                                                     day, based on liver
                                                     toxicity
                                                     (centrilobular
                                                     hepatocellular
                                                     hypertrophy)
                                                    Females
                                                    NOAEL = 66 mg/kg/day
                                                    LOAEL = 204 mg/kg/
                                                     day, based on
                                                     decreased body
                                                     weight, body weight
                                                     gain, liver
                                                     toxicity
                                                     (centrilobular
                                                     hepatocellular
                                                     hypertrophy), and
                                                     lung lesions (heart
                                                     failure cells and
                                                     interstitial
                                                     fibrosis)
                                                    No evidence of
                                                     carcinogenicity
------------------------------------------------------------------------
870.5100                         Bacterial reverse  Negative
                                  mutation          Concentrations 313-
                                                     5,000 [mu]g/plate
------------------------------------------------------------------------
870.5300                         In vitro           Negative
                                  mammalian cell    Concentrations 500-
                                  gene mutation      5,000 [mu]g/mL
------------------------------------------------------------------------
870.5300                         In vitro           Negative
                                  mammalian cell    10,000 mg/kg
                                  gene mutation
------------------------------------------------------------------------
870.5300                         In vitro           Negative
                                  mammalian cell
                                  gene mutation
------------------------------------------------------------------------
870.5550                         Unscheduled DNA    Negative
                                  synthesis (rat    Concentrations 10 to
                                  hepatocyte         507 [mu]g/mL
                                  cells)
------------------------------------------------------------------------
870.5915                         In vivo sister     Negative
                                  chromatid         Dose 0, 0.5, 1.67, 5
                                  exchange           gram (g)/kg
                                  (chinese hamster
                                  bone marrow)
------------------------------------------------------------------------
870.7485                         Metabolism and     Excretion is
                                  pharmacokinetics   extremely rapid and
                                  (rats)             tissue accumulation
                                                     is negligible,
                                                     assuming DMSO
                                                     vehicle does not
                                                     affect excretion or
                                                     storage of NP-55,
                                                     78% excreted into
                                                     urine and 20.1% in
                                                     feces
------------------------------------------------------------------------
870.7485                         Metabolism and     Administration of
                                  pharmacokinetics   radioactively
                                  (rats)             labeled NP-55
                                                     yielded 0.8%
                                                     radioactivity in
                                                     urine identified as
                                                     hydroxymetabolites
                                                     represented by 6-OH
                                                     M2SO2 and 2 other
                                                     metabolites found
                                                     by mass
                                                     spectrometry were
                                                     MSO and M1SO
------------------------------------------------------------------------


[[Page 55862]]

B. Toxicological Endpoints

    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. A UF of 100 is routinely used, 10X to account for 
interspecies differences and 10X for intraspecies differences. 
Acceptable developmental toxicity studies were performed in rats and 
rabbits, with evidence of neurotoxicity in the rat study, and an 
acceptable 2-generation reproduction study in rats. The developmental 
toxicity rabbit study did not exhibit either quantitative of 
qualitative susceptibility. Neurotoxicity studies are not available. 
Although, the Agency has concluded that there is a concern for prenatal 
and/or postnatal toxicity resulting from exposure to sethoxydim, the 
concern is reduced because the fetal effects in the developmental rat 
study were seen only at the high dose. Concern is also low because the 
LOAEL for offspring toxicity for the 2-generation reproduction rat 
study is based on conservative determinations of offspring toxicity. 
However, due to lack of subchronic and developmental neurotoxicity 
studies with evidence of developmental (tail) abnormalities in the rat 
developmental and reproductive studies the additional 10X FQPA safety 
factor (SF) in the form of a data base UF was retained.
    For dietary risk assessment (other than cancer) the Agency uses the 
UF to calculate an acute or chronic reference dose (aRfD or cRfD) where 
the reference dose (RfD) is equal to the NOAEL divided by the 
appropriate UF (RfD = NOAEL/UF). Where an additional SF is retained due 
to concerns unique to the FQPA, this additional factor is applied to 
the RfD by dividing the RfD by such additional factor. The acute or 
chronic Population Adjusted Dose (aPAD or cPAD) is a modification of 
the RfD to accommodate this type of FQPA SF.
    For non-dietary risk assessments (other than cancer) the UF is used 
to determine the LOC. For example, when 100 is the appropriate UF (10X 
to account for interspecies differences and 10X for intraspecies 
differences, the LOC is 100. To estimate risk, a ratio of the NOAEL to 
exposures (margin of exposure (MOE) = NOAEL/exposure) is calculated and 
compared to the LOC.
    The linear default risk methodology (Q*) is the primary method 
currently used by the Agency to quantify carcinogenic risk. The Q* 
approach assumes that any amount of exposure will lead to some degree 
of cancer risk. A Q* is calculated and used to estimate risk which 
represents a probability of occurrence of additional cancer cases 
(e.g., risk is expressed as 1 x 10-\6\ or one in a million). 
Under certain specific circumstances, MOE calculations will be used for 
the carcinogenic risk assessment. In this non-linear approach, a 
``point of departure'' is identified below which carcinogenic effects 
are not expected. The point of departure is typically a NOAEL based on 
an endpoint related to cancer effects though it may be a different 
value derived from the dose response curve. To estimate risk, a ratio 
of the point of departure to exposure (MOEcancer = point of 
departure/exposures) is calculated. A summary of the toxicological 
endpoints for sethoxydim used for human risk assessment is shown in the 
following Table 2:

      Table 2.--Summary of Toxicological Dose and Endpoints for Sethoxydim for Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
                                                                  Special FQPA SF* and
          Exposure Scenario               Dose Used in Risk       Level of Concern for   Study and Toxicological
                                            Assessment, UF          Risk Assessmentk             Effects
----------------------------------------------------------------------------------------------------------------
Acute dietary (Females 13-50 years of  NOAEL = 180 mg/kg/day)   Special FQPA SF = 1X     Rat developmental
 age and including infants and         UF = 1,000.............  aPAD = acute RfD /.....   toxicity
 children)                             Acute RfD = 0.18 mg/kg/  Special FQPA SF = 0.18   Developmental
                                        day.                     mg/kg/day.              LOAEL = 650 mg/kg/day
                                                                                          based on decreased
                                                                                          fetal body weight,
                                                                                          tail abnormalities,
                                                                                          delayed ossification
----------------------------------------------------------------------------------------------------------------
Acute dietary                          NOAEL = 180 mg/kg/day    Special FQPA SF = 1X     Rat developmental
(General population).................  UF = 1,000.............  aPAD = acute RfD /.....   toxicity
                                       Acute RfD = 0.18 mg/kg/  Special FQPA SF = 0.18   Maternal
                                        day.                     mg/kg/day.              LOAEL = 650 mg/kg/day
                                                                                          based on irregular
                                                                                          gait that was observed
                                                                                          in 12/34 dams on the
                                                                                          first day of dosing
----------------------------------------------------------------------------------------------------------------
Chronic dietary                        NOAEL= 14 mg/kg/day      Special FQPA SF = 1X     Mouse carcinogenicity
(All populations)....................  UF = 1,000.............  cPAD = chronic RfD /...   study
                                       Chronic RfD = 0.014 mg/  Special FQPA SF = 0.014  LOAEL = 41 mg/kg/day
                                        kg/day.                  mg/kg/day.               based on liver
                                                                                          hypertrophy and fatty
                                                                                          degeneration
----------------------------------------------------------------------------------------------------------------
Short-term                             NOAEL= 180 mg/kg/day     Residential              Rat developmental
Incidental oral (1-30 days)..........                           LOC for MOE = 1,000....   toxicity
                                                                                         Maternal
                                                                                         LOAEL = 650 mg/kg/day
                                                                                          based on irregular
                                                                                          gait that was observed
                                                                                          in 12/34 dams on the
                                                                                          first day of dosing
----------------------------------------------------------------------------------------------------------------
Intermediate-term                      NOAEL = 45.6 mg/kg/day   Residential              90-Day mouse oral
Incidental oral (1-6 months).........                           LOC for MOE = 1,000....   toxicity
                                                                                         LOAEL = 137 mg/kg/day
                                                                                          based on increased
                                                                                          liver weight and
                                                                                          hepatocellular
                                                                                          hypertrophy
----------------------------------------------------------------------------------------------------------------

[[Page 55863]]

 
Short-term dermal (1 to 30 days)       Dermal (or oral) study   Residential              Quantification of
                                       NOAEL= NA..............  LOC for MOE = NA.......   dermal exposure risk
                                                                                          assessment is not
                                                                                          required because of
                                                                                          lack of dermal and pre-
                                                                                          natal toxicity in
                                                                                          rabbits, and the low
                                                                                          dermal absorption
                                                                                          physical and chemical
                                                                                          properties of
                                                                                          sethoxydim
----------------------------------------------------------------------------------------------------------------
Intermedia-term dermal (1 to 6         Dermal (or oral) study   Residential              Quantification of
 months)                               NOAEL = NA.............  LOC for MOE = NA.......   dermal exposure risk
                                                                                          assessment is not
                                                                                          required because of
                                                                                          lack of dermal and
                                                                                          prenatal toxicity in
                                                                                          rabbits, and the low
                                                                                          dermal absorption
                                                                                          physical and chemical
                                                                                          properties of
                                                                                          sethoxydim
----------------------------------------------------------------------------------------------------------------
Long-term dermal > 6 months)           Dermal (or oral) study   Residential              Quantification of
                                       NOAEL= NA..............  LOC for MOE = NA.......   dermal exposure risk
                                                                                          assessment is not
                                                                                          required because of
                                                                                          lack of dermal and
                                                                                          prenatal toxicity in
                                                                                          rabbits, and the low
                                                                                          dermal absorption
                                                                                          physical and chemical
                                                                                          properties of
                                                                                          sethoxydim
----------------------------------------------------------------------------------------------------------------
Short-term                             Inhalation study         Residential              28-Day rat inhalation
Inhalation (1 to 30 days)............  NOAEL= 81 mg/kg/day....  LOC for MOE = 1,000....  LOAEL = 651 mg/kg/day
                                                                                          based on increased
                                                                                          liver weight, clinical
                                                                                          chemistry (increased
                                                                                          total serum
                                                                                          bilirobin), and liver
                                                                                          histopathology
----------------------------------------------------------------------------------------------------------------
Intermediate-term                      Inhalation study         Residential              28-Day rat inhalation
Inhalation (1 to 6 months)...........  NOAEL = 81 mg/kg/day...  LOC for MOE = 1,000....  LOAEL = 651 mg/kg/day
                                                                                          based on increased
                                                                                          liver weight, clinical
                                                                                          chemistry (increased
                                                                                          total serum
                                                                                          bilirobin), and liver
                                                                                          histopathology
----------------------------------------------------------------------------------------------------------------
Cancer (oral, dermal, inhalation)           ``Not likely human carcinogen'' based on the lack of evidence of
                                                            carcinogenicity in rats and mice
----------------------------------------------------------------------------------------------------------------
UF = uncertainty factor, FQPA SF = Special FQPA safety factor, NOAEL = no-observed-adverse-effect-level, LOAEL =
  lowest-observed-adverse-effect-level, PAD = population-adjusted dose (a = acute, c = chronic) RfD = reference
  dose, MOE = margin of exposure, LOC = level of concern, NA = Not Applicable.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. Tolerances have been 
established (40 CFR 180.412) for the combined residues of sethoxydim 
and its metabolites, in or on a variety of raw agricultural 
commodities. Tolerances are also currently established for secondary 
residues in meat, fat, and meat byproducts of cattle, goats, hogs, 
horses, poultry, and sheep at 0.2 ppm (except 2.0 ppm in poultry meat 
byproducts); eggs at 2.0 ppm, and milk at 0.05 ppm. Time limited 
tolerances (to expire by 12/31/03) are established for residues in milk 
at 0.5 ppm and the meat byproducts of cattle, goats, hogs, horses, and 
sheep at 1.0 ppm. Risk assessments were conducted by EPA to assess 
dietary exposures from sethoxydim in food as follows:
    i. Acute exposure. Acute dietary 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. This acute assessment used tolerance level residues 
for most of the crops but limited refinement was obtained though the 
incorporation of field trial data and experimental processing factors 
for some of the crops expected to be more highly associated with 
dietary exposure to sethoxydim. Specifically, field trial data were 
incorporated for apples, pears, and other pome fruits, grapes, oranges, 
potatoes, strawberries, peaches, succulent green peas, succulent green 
beans, and succulent lima beans. Empirical processing data for apples, 
grapes, tomatoes, potatoes and oranges were also used. The processing 
data for orange juice was also translated to other citrus juices. 
Percent crop treated (PCT) information was available for most crops and 
was used wherever possible to refine the assessment. Tolerance level 
residues were used for meat, poultry, milk and eggs. With the 
refinements incorporated in this assessment, the acute dietary analyses 
for sethoxydim show that the estimated risks from acute dietary 
exposure to sethoxydim are below <100% aPAD for the U.S. population.
    ii. Chronic exposure. In conducting this chronic dietary risk 
assessment the Dietary Exposure Evaluation Model (DEEMTM) 
analysis evaluated the individual food consumption as reported by 
respondents in the U.S. Department of Agriculture (USDA) 1989-1992 
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: The chronic 
analyses (limited refined dietary risk assessment) used tolerance level 
residues for all crops and the PCT for many crops. For the chronic 
analyses, refinement was obtained by calculation of anticipated 
residues for meat and

[[Page 55864]]

milk, and without using field trial data. The results of this analysis 
indicate that the chronic dietary risk (food only) associated with 
existing uses of sethoxydim is below <100% cPAD for the U.S. 
population.
    iii. Cancer. Sethoxydim is classified as ``not likely to be a human 
carcinogen''. Therefore, a quantitative assessment of aggregate cancer 
risk was not performed.
    iv. Anticipated residue and PCT information. Section 408(b)(2)(E) 
of the 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 chemicals that have been measured in food. 
If EPA relies on such information, EPA must 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. Following the initial data submission, EPA is 
authorized to require similar data on a time frame it deems 
appropriate. As required by section 408(b)(2)(E) of the FFDCA, EPA will 
issue a Data Call-In for information relating to anticipated residues 
to be submitted no later than 5 years from the date of issuance of this 
tolerance.
    Section 408(b)(2)(F) of the FFDCA states that the Agency may use 
data on the actual percent of food treated for assessing chronic 
dietary risk only if the Agency can make the following findings: 
Condition 1, that the data used are reliable and provide a valid basis 
to show what percentage of the food derived from such crop is likely to 
contain such pesticide residue; condition 2, that the exposure estimate 
does not underestimate exposure for any significant subpopulation 
group; and condition 3, if data are available on pesticide use and food 
consumption in a particular area, the exposure estimate does not 
understate exposure for the population in such area. In addition, the 
Agency must provide for periodic evaluation of any estimates used. To 
provide for the periodic evaluation of the estimate of PCT as required 
by section 408(b)(2)(F) of the FFDCA, EPA may require registrants to 
submit data on PCT.
    The Agency used PCT information as follows.
    Alfalfa 0.1%; apples 0.1%; apricot 0.02%; asparagus 5%; beans, lima 
9%; beans/peas, dried 14%; beets, sugar 8%; broccoli 1%; cabbage 1%; 
canola 4%; cantaloupe 8%; carrots 2%; cauliflower 2%; cherries 0.4%; 
collards 2%; corn, field 0.1%; corn, sweet 0.5%; cotton 0.5%; 
cranberries 8%; cucumbers 6%; eggplant/peppers 5%; flax 38%; grapefruit 
1%; grapes 1%; lemons 5%; lettuce 1%; nectarines 0.1%; oranges 3%; 
peaches 0.4%; peanuts 5%; peppers, bell 3%; peppers, chili 11%; pears 
0.03%; peas, green 2%; potatoes 4%; potatoes, sweet 18%; pumpkins 8%; 
root/tuber vegetables (other than carrots, potatoes, and sugar beets) 
5%; soybeans 2%; spinach 0.3%; squash 8%; strawberries 5%; sunflowers 
14%; tomatoes 4%; vegetables, other 6%; watermelons 12%.
    The Agency believes that the three conditions listed in Unit IV 
have been met. With respect to condition 1, PCT estimates are derived 
from Federal and private market survey data, which are reliable and 
have a valid basis. EPA uses a weighted average PCT for chronic dietary 
exposure estimates. This weighted average PCT figure is derived by 
averaging State-level data for a period of up to 10 years, and 
weighting for the more robust and recent data. A weighted average of 
the PCT reasonably represents a person's dietary exposure over a 
lifetime, and is unlikely to underestimate exposure to an individual 
because of the fact that pesticide use patterns (both regionally and 
nationally) tend to change continuously over time, such that an 
individual is unlikely to be exposed to more than the average PCT over 
a lifetime. For acute dietary exposure estimates, EPA uses an estimated 
maximum PCT. The exposure estimates resulting from this approach 
reasonably represent the highest levels to which an individual could be 
exposed, and are unlikely to underestimate an individual's acute 
dietary exposure. The Agency is reasonably certain that the percentage 
of the food treated is not likely to be an underestimation. As to 
conditions 2 and 3, regional consumption information and consumption 
information for significant subpopulations is taken into account 
through EPA's computer-based model for evaluating the exposure of 
significant subpopulations including several regional groups. Use of 
this consumption information in EPA's risk assessment process ensures 
that EPA's exposure estimate does not understate exposure for any 
significant sub population group and allows the Agency to be reasonably 
certain that no regional population is exposed to residue levels higher 
than those estimated by the Agency. Other than the data available 
through national food consumption surveys, EPA does not have available 
information on the regional consumption of food to which sethoxydim may 
be applied in a particular area.
    2. Dietary exposure from drinking water. The Agency lacks 
sufficient monitoring exposure data to complete a comprehensive dietary 
exposure analysis and risk assessment for sethoxydim in drinking water. 
Because the Agency does not have comprehensive monitoring data, 
drinking water concentration estimates are made by reliance on 
simulation or modeling taking into account data on the physical 
characteristics of sethoxydim.
    The Agency uses the First Index Reservoir Screening Tool (FIRST) or 
the Pesticide Root Zone/Exposure Analysis Modeling System (PRZM/EXAMS), 
to produce estimates of pesticide concentrations in an index reservoir. 
The Screening Concentration in Groundwater (SCI-GROW) model is used to 
predict pesticide concentrations in shallow ground water. For a 
screening-level assessment for surface water EPA will use FIRST (a Tier 
1 model) before using PRZM/EXAMS (a Tier 2 model). The FIRST model is a 
subset of the PRZM/EXAMS model that uses a specific high-end runoff 
scenario for pesticides. While both FIRST and PRZM/EXAMS incorporate an 
index reservoir environment, the PRZM/EXAMS model includes a percent 
crop area factor as an adjustment to account for the maximum percent 
crop coverage within a watershed or drainage basin.
    None of these models include consideration of the impact processing 
(mixing, dilution, or treatment) of raw water for distribution as 
drinking water would likely have on the removal of pesticides from the 
source water. The primary use of these models by the Agency at this 
stage is to provide a coarse screen for sorting out pesticides for 
which it is highly unlikely that drinking water concentrations would 
ever exceed human health levels of concern.
    Since the models used are considered to be screening tools in the 
risk assessment process, the Agency does not use estimated 
environmental concentrations (EECs) from these models to quantify 
drinking water exposure and risk as a percent reference dose (%RfD or 
percent population adjusted dose (%PAD)). Instead, drinking water 
levels of comparison (DWLOCs) are calculated and used as a point of 
comparison against the model estimates of a pesticide's concentration 
in water. DWLOCs are theoretical upper limits on a pesticide's 
concentration in drinking water in light of total aggregate exposure to 
a pesticide in food, and from residential uses. Since DWLOCs address 
total aggregate exposure to sethoxydim they are further discussed in 
the aggregate risk section Unit III. E.
    Based on the FIRST and SCI-GROW models the EECs of sethoxydim for

[[Page 55865]]

acute exposures are estimated to be 100 parts per billion (ppb) for 
surface water and 1 ppb for ground water. The EECs for chronic 
exposures are estimated to be 20 ppb for surface water and 1 ppb for 
ground 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). Sethoxydim is 
currently registered for use on the following residential non-dietary 
sites: Ornamentals and flowering plants, recreational areas, and 
buildings/structures (non-agricultural-outdoor). The risk assessment 
was conducted using the following exposure assumptions:

    i. Residential handler. There is potential sethoxydim exposure to 
residential handlers who mix, load and apply sethoxydim for use on 
residential turf and ornamentals. Because dermal toxicity endpoints 
were not identified, only the following exposure scenarios were 
assessed:
    [sbull] Adult inhalation exposure from mixing/loading/applying 
sethoxydim for spot treatment with a low-pressure handwand.
    [sbull] Adult inhalation exposure from mixing/loading/applying 
sethoxydim for spot treatment with a hose-end sprayer.
    ii. Residential post-application. The labeled use pattern for 
sethoxydim only suggests spot treatments for non-agricultural sites 
(e.g., fence lines, at base of ornamental plantings, etc.). The Agency 
considered the potential residential post-application exposure from 
spot treatment to be negligible. However, an exposure/risk assessment 
for broadcast turf treatment, using the applicable endpoints, was 
included in this assessment because there is no labeled recommendation 
against broadcast treatment of lawns. Sethoxydim treatment may take up 
to 3 weeks before visible burnback of turf is seen, and the previous 
risk assessment for other agricultural use sites included residential 
post-application exposure from turf use.
    Broadcast turf treatment would result in the potential for dermal 
(adults and children) and incidental oral exposure (children only) 
during post-application activities. However, because the appropriate 
dermal toxicity endpoints for sethoxydim were not identified, and 
because inhalation is considered negligible for post-application 
exposure, only the following post-application exposure scenarios were 
assessed:
    1. Incidental non-dietary ingestion of pesticide residues on lawns 
from hand-to-mouth transfer.
    2. Incidental non-dietary ingestion of residues from object-to-
mouth activities (pesticide-treated turfgrass).
    3. Incidental non-dietary ingestion of soil (base of pesticide-
treated ornamentals).
    Post-application exposures from various activities following lawn 
treatment are considered to be the most common and significant in 
residential settings.
    The exposure via incidental non-dietary ingestion involving other 
plant material (i.e., resulting from children's handling of treated 
ornamentals) may occur but is considered negligible.
    The exposure and risk estimates for the three residential exposure 
scenarios are assessed for the day of application (day ``0'') because 
it is assumed that toddlers could contact the lawn immediately after 
application. On the day of application, it was assumed that 5% of the 
application rate is available from the turf grass as transferrable 
residue (20% for object-to-mouth activities). Intermediate-term 
exposure is also expected (up to 6 months) because reapplications are 
not limited, and may be necessary to continue suppression of grass. The 
application rates used for turf and ornamental gardens are 0.33 and 
0.49 lb active ingredient acres (ai/A) respectively.
    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.''
    EPA does not have, at this time, available data to determine 
whether sethoxydim has a common mechanism of toxicity with other 
substances. 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 sethoxydim 
and any other substances and sethoxydim 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 sethoxydim 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 the FFDCA provides that EPA will 
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 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 margin of exposure 
(MOE) analysis or through using uncertainty (safety) factors in 
calculating a dose level that poses no appreciable risk to humans.
    2. Prenatal and postnatal sensitivity. EPA determined that there 
are no residual uncertainties for prenatal and/or postnatal toxicity 
based on the following:
    i. There was evidence of qualitative susceptibility in the 
developmental rat study with the occurrence of more severe effects in 
the fetuses (tail abnormalities and delayed ossification) than the 
maternal animals (clinical signs of neurotoxicity). Tail abnormalities 
were also seen in the F1a and F1b offspring of the 2-generation 
reproduction rat study. However, the degree of concern is low for the 
fetal effects in the developmental rat study since the fetal anomalies 
were seen only at the high dose 650 mg/kg/day which is close to the 
Limit Dose (LTD) (1,000 mg/kg/day). They were seen in the presence of 
maternal toxicity (clinical signs of neurotoxicity) and clear NOAELs/
LOAELs were established for maternal and developmental toxicities.
    ii. Evidence of quantitative susceptibility was indicated in the 2-
generation reproduction rat study, by a slightly higher decrease (11-
13%) in the body weights of offspring during lactation as compared to 
an 8-10% decrease in the body weights of the parental animals. Again, 
the degree of concern is also low for the 2-generation reproduction rat 
study since the LOAEL for offspring toxicity is based on a conservative 
determination of a minimal response in pup body weight decrements at 
the same dose that also caused decreases in body weights in the 
parental animals.

[[Page 55866]]

    iii. The developmental toxicity study in the rabbits did not 
exhibit either quantitative or qualitative susceptibility.
    3. Conclusion. Exposure data for sethoxydim are complete or are 
estimated based on data that reasonably accounts for potential 
exposures. The toxicity data base, however, is not complete. Due to 
evidence of developmental (Tail) abnormalities in the rat developmental 
and reproductive studies, EPA has required submission of subchronic and 
developmental neurotoxicity studies. After reviewing the data base, EPA 
concluded that there was not a reliable basis for establishing an 
additional safety factor for the protection of children at a value 
different than the statutory default of 10X. Accordingly, EPA has 
retained the additional 10X FQPA safety factor in the form of a Data 
base Uncertainty Factor.

E. Aggregate Risks and Determination of Safety

    To estimate total aggregate exposure to a pesticide from food, 
drinking water, and residential uses, the Agency calculates DWLOCs 
which are used as a point of comparison against the model estimates of 
a pesticide's concentration in water (EECs). DWLOC values are not 
regulatory standards for drinking water. DWLOCs are theoretical upper 
limits on a pesticide's concentration in drinking water in light of 
total aggregate exposure to a pesticide in food and residential uses. 
In calculating a DWLOC, the Agency determines how much of the 
acceptable exposure (i.e., the PAD) is available for exposure through 
drinking water [e.g., allowable chronic water exposure (mg/kg/day) = 
cPAD - (average food + residential exposure)]. This allowable exposure 
through drinking water is used to calculate a DWLOC.
    A DWLOC will vary depending on the toxic endpoint, drinking water 
consumption, and body weights. Default body weights and consumption 
values as used by the U.S. EPA Office of Water are used to calculate 
DWLOCs: 2 L/70 kg (adult male), 2L/60 kg (adult female), and 1L/10 kg 
(child). Default body weights and drinking water consumption values 
vary on an individual basis. This variation will be taken into account 
in more refined screening-level and quantitative drinking water 
exposure assessments. Different populations will have different DWLOCs. 
Generally, a DWLOC is calculated for each type of risk assessment used: 
Acute, short-term, intermediate-term, chronic, and cancer.
    When EECs for surface water and ground water are less than the 
calculated DWLOCs, OPP concludes with reasonable certainty that 
exposures to the pesticide in drinking water (when considered along 
with other sources of exposure for which EPA has reliable data) would 
not result in unacceptable levels of aggregate human health risk at 
this time. Because EPA considers the aggregate risk resulting from 
multiple exposure pathways associated with a pesticide's uses, levels 
of comparison in drinking water may vary as those uses change. If new 
uses are added in the future, EPA will reassess the potential impacts 
of residues of the pesticide in drinking water as a part of the 
aggregate risk assessment process.
    1. Acute risk. Using the exposure assumptions discussed in this 
unit for acute exposure, the acute dietary exposure from food to 
sethoxydim will occupy 52% of the aPAD for the U.S. population, 92% of 
the aPAD for children aged 1-2 and 92% of the aPAD for children aged 3-
5. In addition, there is potential for acute dietary exposure to 
sethoxydim in drinking water. After calculating DWLOCs and comparing 
them to the EECs for surface and ground water, EPA does not expect the 
aggregate exposure to exceed 100% of the aPAD, as shown in the 
following Table 3:

                      Table 3.--Aggregate Risk Assessment for Acute Exposure to Sethoxydim
----------------------------------------------------------------------------------------------------------------
                                                               Acute Food    Surface       Ground
              Population Subgroup                 aPAD (mg/    Exp mg/kg/   Water EEC    Water EEC   Acute DWLOC
                                                     kg)          day         (ppb)1       (ppb)1       (ppb)2
----------------------------------------------------------------------------------------------------------------
General U.S. population                                 0.18        0.096          100          1.0        2,940
----------------------------------------------------------------------------------------------------------------
Children 1-2 years                                      0.18        0.165          100          1.0          150
----------------------------------------------------------------------------------------------------------------
Children 3-5 years                                      0.18        0.165          100          1.0          152
----------------------------------------------------------------------------------------------------------------
1 The crop producing the highest risk level was used.
2 Chronic DWLOC( [mu]g/L) = maximum chronic water exposure (mg/kg/day) x body weight (kg) water consumption (L)
  x 103 mg/[mu]g.

    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that exposure to 
sethoxydim from food will utilize 24% of the cPAD for the U.S. 
population, and 75% of the cPAD for infants <1 year old. Based on the 
use pattern, chronic residential exposure to residues of sethoxydim is 
not expected. In addition, there is potential for chronic dietary 
exposure to sethoxydim in drinking water. After calculating DWLOCs and 
comparing them to the EECs for surface and ground water, EPA does not 
expect the aggregate exposure to exceed 100% of the cPAD, as shown in 
the following Table 4:

              Table 4.-- Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Sethoxydim.
----------------------------------------------------------------------------------------------------------------
                                                                Chronic      Surface       Ground      Chronic
              Population Subgroup                 cPAD (mg/   Food Exp mg/  Water EEC    Water EEC      DWLOC
                                                     kg)         kg/day       (ppb)1       (ppb)1       (ppb)2
----------------------------------------------------------------------------------------------------------------
General U.S. population                                0.014       0.0038           20          1.0          358
----------------------------------------------------------------------------------------------------------------
Infants (<1 year)                                      0.014       0.0105           20          1.0         35.3
----------------------------------------------------------------------------------------------------------------
1 The crop producing the highest level was used.
2 Chronic DWLOC ([mu]g/L) = [maximum chronic water exposure (mg/kg/day) x body weight (kg)] / [water consumption
  (L) x 10-3 mg/[mu]g.]


[[Page 55867]]

    3. Short-term risk (1-30 days). Short-term aggregate exposure takes 
into account residential exposure plus chronic exposure to food and 
water (considered to be a background exposure level).
    Sethoxydim is currently registered for uses that could result in 
short-term residential exposure and the Agency has determined that it 
is appropriate to aggregate chronic food and water and short-term 
exposures for sethoxydim.

    Using the exposure assumptions described in this unit for short-
term exposures, EPA has concluded that food and residential exposures 
aggregated result in aggregate MOEs of greater than 1,000 for all 
exposure scenarios in children aged 1-2 years, which includes oral 
hand-to-mouth, oral object-to-mouth and soil ingestion. These aggregate 
MOEs do not exceed the Agency's level of concern for aggregate exposure 
to food and residential uses. Short-term aggregate risk assessments 
were not calculated for adult handlers because oral and inhalation 
endpoints lack a common toxicity endpoint. The children 1-2 years-of-
age scenario was chosen because it was the highest estimated food 
exposure and thus, also protective of children 3-5 years of age. In 
addition, short-term DWLOCs were calculated and compared to the EECs 
for chronic exposure of sethoxydim in ground and surface water. After 
calculating DWLOCs and comparing them to the EECs for surface water and 
ground water, EPA does not expect short-term aggregate exposure to 
exceed the Agency's level of concern, as shown in the following Table 
5:

                    Table 5.--Aggregate Risk Assessment for Short-Term Exposure to Sethoxydim
----------------------------------------------------------------------------------------------------------------
                                                                 Target
                                                                Maximum      Surface       Ground     Short-Term
              Population Subgroup                 Target MOE   Exposure1    Water EEC2   Water EEC2  DWLOC (ppb)
                                                              (mg/kg/day)     (ppb)        (ppb)
----------------------------------------------------------------------------------------------------------------
Children 1-2 years old                                 1,000         0.18          2 0            1        1,650
----------------------------------------------------------------------------------------------------------------
1 Target Maximum Exposure = NOAEL/Target MOE.
2 Estimate for the highest use rate was chosen.

    4. Intermediate-term risk (1-6 months). Intermediate-term aggregate 
exposure takes into account residential exposure plus chronic exposure 
to food and water (considered to be a background exposure level).
    Sethoxydim is currently registered for use(s) that could result in 
intermediate-term residential exposure and the Agency has determined 
that it is appropriate to aggregate chronic food and water and 
intermediate-term exposures for sethoxydim.
    Using the exposure assumptions described in this unit for 
intermediate-term exposures, EPA has concluded that food and 
residential exposures aggregated result in aggregate MOEs of greater 
than 1,000 for all exposure scenarios in children aged 1-2 years old, 
which includes oral hand-to-mouth, oral object-to-mouth and soil 
ingestion. These aggregate MOEs do not exceed the Agency's level of 
concern for aggregate exposure to food and residential uses. 
Intermediate term aggregate risk assessments were not calculated for 
adult handlers because oral and inhalation endpoints lack a common 
toxicity endpoint. The children 1-2 years- of -age scenario were chosen 
because it was the highest estimated food exposure and thus, also 
protective of children 3-5 years of age. After calculating DWLOCs and 
comparing them to the EECs for surface water and ground water, EPA does 
not expect intermediate-term aggregate exposure to exceed the Agency's 
level of concern, as shown in the following Table 6:

                Table 6.--Aggregate Risk Assessment for Intermediate-Term Exposure to Sethoxydim
----------------------------------------------------------------------------------------------------------------
                                                               Target
                                                              Maximum      Surface       Ground    Intermediate-
             Population Subgroup                Target MOE   Exposure1    Water EEC2   Water EEC     Term DWLOC
                                                            (mg/kg/day)     (ppb)        (ppb)         (ppb)
----------------------------------------------------------------------------------------------------------------
Children 1-2 years old                               1,000        0.046           20            1           330
----------------------------------------------------------------------------------------------------------------
1Target Maximum Exposure = NOAEL/Target MOE.
2Estimate for the highest use rate was chosen.

    5. Aggregate cancer risk for U.S. population. Sethoxydim is not 
expected to pose a cancer risk because no evidence of carcinogenicity 
was found in adequate animal tests in two different species.
    6. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to the general population, and to infants and children from aggregate 
exposure to sethoxydim residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology (gas-liquid chromatography with 
flame photometric detection (GLC/FPD) in the sulfur mode) is available 
[BASF Wyandotte Corporation's (BWC's) Method No. 30, 3/15/82; MRID 
44864501; Method I, PAM II] to enforce the tolerance expression in 
plant and livestock commodities.

B. International Residue Limits

    There are no Codex, Canadian, or Mexican maximum residue limits or 
tolerances for sethoxydim on lingonberry, juneberry, salal, or 
safflower. Therefore, international harmonization is not an issue for 
the proposed uses of sethoxydim on lingonberry, juneberry, salal, 
pistachio, or safflower.
    There are no Codex or Mexican maximum residue limits or tolerances 
for sethoxydim on sweet corn. There is a Canadian tolerance on corn of 
0.5 ppm for sethoxydim and metabolites

[[Page 55868]]

containing the cyclohex-2-enone moiety expressed as sethoxydim. The 
tolerance for the proposed use of sethoxydim on sweet corn is not being 
harmonized with the Canadian tolerance until the Agency can revise its 
risk assessment to evaluate the risks of the harmonization with the 
Canadian tolerance.

C. Conditions

    As a condition of registration, the registrant must submit:
    1. Residue chemistry. i. To support the proposed use on safflower, 
storage stability data for sethoxydim, MSO, and 5-OH-MSO2 in safflower 
oil (or another oil) stored frozen for 1 year are needed since storage 
stability data for sethoxydim residues in oil have not previously been 
submitted.
    ii. As recommended in OPPTS 860.1500, five field trials are 
required for safflower, with suggested distribution in Region 7 (two 
Trials) and Region 10 (three Trials). Four studies, which were 
conducted in 1988, were submitted from Region 10 (one study), Region 5 
(two studies), and Region 7 (one study). EPA has determined that two 
additional studies from Region 10 must be submitted.
    2. Toxicology. i. Subchronic neurotoxicity study--rat.
    ii. Developmental neurotoxicity study (DNT)--rat.

V. Conclusion

    Therefore, tolerances are established for the combined residues of 
sethoxydim, (2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-
hydroxy-2-cyclohexen-1-one) and its metabolites containing the 2-
cyclohexen-1-one moiety (calculated as the herbicide), in or on corn, 
sweet, kernels plus cob with husk removed at 0.4 parts per million 
(ppm); corn, sweet, forage at 3.0 ppm; corn, sweet, stover at 3.5 ppm; 
lingonberry at 5.0 ppm; juneberry at 5.0 ppm; milk at 0.5 ppm; cattle, 
meat byproducts at 1.0 ppm; goat, meat byproducts at 1.0 ppm; hog, meat 
byproducts at 1.0 ppm; horse, meat byproducts at 1.0 ppm; sheep, meat 
byproducts at 1.0 ppm; pistachio at 0.2 ppm; safflower at 15.0 ppm and 
salal at 5.0 ppm.

VI. Objections and Hearing Requests

    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. EPA's procedural 
regulations which govern the submission of objections and requests for 
hearings appear in 40 CFR part 178. Although the procedures in those 
regulations require some modification to reflect the amendments made to 
the FFDCA by the FQPA, EPA will continue to use those procedures, with 
appropriate adjustments, until the necessary modifications can be made. 
The new section 408(g) of the FFDCA provides essentially the same 
process for persons to ``object'' to a regulation for an exemption from 
the requirement of a tolerance issued by EPA under new section 408(d) 
of FFDCA, as was provided in the old sections 408 and 409 of the FFDCA. 
However, the period for filing objections is now 60 days, rather than 
30 days.

A. What Do I Need to Do to File an Objection or Request a Hearing?

    You must file your objection or request a hearing on this 
regulation in accordance with the instructions provided in this unit 
and in 40 CFR part 178. To ensure proper receipt by EPA, you must 
identify docket ID number OPP-2003-0315 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 November 
28, 2003.
    1. Filing the request. Your objection must specify the specific 
provisions in the regulation that you object to, and the grounds for 
the objections (40 CFR 178.25). If a hearing is requested, the 
objections must include a statement of the factual issues(s) on which a 
hearing is requested, the requestor's contentions on such issues, and a 
summary of any evidence relied upon by the objector (40 CFR 178.27). 
Information submitted in connection with an objection or hearing 
request may be claimed confidential by marking any part or all of that 
information as CBI. Information so marked will not be disclosed except 
in accordance with procedures set forth in 40 CFR part 2. A copy of the 
information that does not contain CBI must be submitted for inclusion 
in the public record. Information not marked confidential may be 
disclosed publicly by EPA without prior notice.
    Mail your written request to: Office of the Hearing Clerk (1900C), 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001. You may also deliver your request to the 
Office of the Hearing Clerk in Rm.104, Crystal Mall 2, 1921 
Jefferson Davis Hwy., Arlington, VA. The Office of the Hearing Clerk is 
open from 8 a.m. to 4 p.m., Monday through Friday, excluding legal 
holidays. The telephone number for the Office of the Hearing Clerk is 
(703) 603-0061.
    2. Tolerance fee payment. If you file an objection or request a 
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or 
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must 
mail the fee to: EPA Headquarters Accounting Operations Branch, Office 
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please 
identify the fee submission by labeling it ``Tolerance Petition Fees.''
    EPA is authorized to waive any fee requirement ``when in the 
judgement of the Administrator such a waiver or refund is equitable and 
not contrary to the purpose of this subsection.'' For additional 
information regarding the waiver of these fees, you may contact James 
Tompkins by phone at (703) 305-5697, by e-mail at [email protected], 
or by mailing a request for information to Mr. Tompkins at Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001.
    If you would like to request a waiver of the tolerance objection 
fees, you must mail your request for such a waiver to: James Hollins, 
Information Resources and Services Division (7502C), Office of 
Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460-0001.
    3. Copies for the Docket. In addition to filing an objection or 
hearing request with the Hearing Clerk as described in Unit VI.A., you 
should also send a copy of your request to the PIRIB for its inclusion 
in the official record that is described in Unit I.B.1. Mail your 
copies, identified by docket ID number OPP-2003-0315, to: Public 
Information and Records Integrity Branch, Information Resources and 
Services Division (7502C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001. In person or by courier, bring a copy to the location of the 
PIRIB described in Unit I.B.1. You may also send an electronic copy of 
your request via e-mail to: [email protected]. Please use an ASCII 
file format and avoid the use of special characters and any form of 
encryption. Copies of electronic objections and hearing requests will 
also be accepted on disks in WordPerfect 6.1/8.0 or ASCII file format. 
Do not include any CBI in your electronic copy. You may also submit an 
electronic copy of your request at many Federal Depository Libraries.

B. When Will the Agency Grant a Request for a Hearing?

    A request for a hearing will be granted if the Administrator 
determines that the material submitted shows the following: There is a 
genuine and substantial issue

[[Page 55869]]

of fact; there is a reasonable possibility that available evidence 
identified by the requestor would, if established, resolve one or more 
of such issues in favor of the requestor, taking into account 
uncontested claims or facts to the contrary; and resolution of the 
factual issues(s) in the manner sought by the requestor would be 
adequate to justify the action requested (40 CFR 178.32).

VII. Statutory and Executive Order Reviews

    This final rule establishes a tolerance under section 408(d) of the 
FFDCA in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled Regulatory Planning and 
Review (58 FR 51735, October 4, 1993). Because this rule has been 
exempted from review under Executive Order 12866 due to its lack of 
significance, this rule is not subject to Executive Order 13211, 
Actions Concerning Regulations That Significantly Affect Energy Supply, 
Distribution, or Use (66 FR 28355, May 22, 2001). This final rule does 
not contain any information collections subject to OMB approval under 
the Paperwork Reduction Act (PRA), 44 U.S.C. 3501 et seq., or impose 
any enforceable duty or contain any unfunded mandate as described under 
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA) (Public Law 
104-4). Nor does it require any special considerations under Executive 
Order 12898, entitled Federal Actions to Address Environmental Justice 
in Minority Populations and Low-Income Populations (59 FR 7629, 
February 16, 1994); or OMB review or any Agency action under Executive 
Order 13045, entitled Protection of Children from Environmental Health 
Risks and Safety Risks (62 FR 19885, April 23, 1997). This action does 
not involve any technical standards that would require Agency 
consideration of voluntary consensus standards pursuant to section 
12(d) of the National Technology Transfer and Advancement Act of 1995 
(NTTAA), Public Law 104-113, section 12(d) (15 U.S.C. 272 note). Since 
tolerances and exemptions that are established on the basis of a 
petition under section 408(d) of the 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 the 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.

VIII. 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 record 
keeping requirements.

    Dated: September 23, 2003.
Debra Edwards,
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), 346(a) and 371.

0
2. Section 180.412 is amended as follows:
0
i. In the table to paragraph (a) by revising the entries for cattle, 
meat byproducts; corn, sweet, kernel plus cob with husks removed; goat 
meat byproducts; hog, meat byproduct; horse, meat byproduct; milk; and 
sheep, meat byproduct, and by alphabetically adding the commodities 
corn, sweet, forage; corn sweet, stover, juneberry; lingonberry; 
pistachio; salal; and safflower.
0
ii. By removing the text from paragraph (b) and reserving the paragraph 
designation and heading.
0
The amended, added, and revised portions of Sec.  180.412 read as 
follows:


Sec.  180.412  Sethoxydim; tolerances for residues.

    (a) * * *

------------------------------------------------------------------------
                                                             Expiration/
                   Commodity                     Parts per    Revocation
                                                  million        Date
------------------------------------------------------------------------
                                * * * * *
Cattle, meat byproducts.......................          1.0         None
                                * * * * *
Corn, sweet, forage...........................          3.0         None
Corn, sweet, kerenel plus cob with husks                0.4         None
 removed......................................

[[Page 55870]]

 
Corn, sweet stover............................          3.5         None
                                * * * * *
Goat, meat byproducts.........................          1.0         None
                                * * * * *
Hog, meat byproducts..........................          1.0         None
                                * * * * *
Horse, meat byproducts........................          1.0         None
                                * * * * *
Juneberry.....................................          5.0         None
                                * * * * *
Lingonberry...................................          5.0         None
                                * * * * *
Milk..........................................          0.5         None
                                * * * * *
Pistachio.....................................          0.2         None
                                * * * * *
Salal.........................................          5.0         None
Safflower.....................................         15.0         None
                                * * * * *
Sheep, meat byproducts........................          1.0         None
                                * * * * *
------------------------------------------------------------------------

    (b) Section 18 emergency exemptions. [Reserved]
* * * * *
[FR Doc. 03-24562 Filed 9-26-03; 8:45 am]
BILLING CODE 6560-50-S