[Federal Register Volume 62, Number 70 (Friday, April 11, 1997)]
[Rules and Regulations]
[Pages 17735-17742]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-9374]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 180, 185, and 186

[OPP-300467; FRL-5598-7]
RIN 2070-AB78


Sethoxydim; Extension of Time-limited Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This document extends the effective dates for the established 
time-limited tolerances for combined residues of the herbicide 2-[1-
(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-
one (also referred to in this document as sethoxydim) and its 
metabolites in or on various raw agricultural commodities. The 
Interregional Research Project Number 4 (IR-4) requested these time 
extensions under the Federal Food, Drug and Cosmetic Act, as amended by 
the Food Quality Protection Act of 1996.

DATES: This regulation becomes effective April 11, 1997. Objections and 
hearing request must be received by June 10, 1997.

ADDRESSES: Written objections and hearing requests, identified by the 
docket control number, [OPP-300467; PP 0E3909, 2E4052, 2E4065, 2E4092, 
and 3E4162], may be submitted to: Hearing Clerk (1900), Environmental 
Protection Agency, Rm. M3708, 401 M

[[Page 17736]]

St., SW., Washington, DC 20460. Fees accompanying objections and 
hearing requests shall be labeled ``Tolerance Petition Fees'' and 
forwarded to: EPA Headquarters Accounting Operations Branch, OPP 
(Tolerance Fees), P.O. Box 360277M, Pittsburgh, PA 15251. A copy of any 
objections and hearing requests filed with the Hearing Clerk should be 
identified by the docket control number and submitted to: Public 
Response and Program Resources Branch, Field Operations Division 
(7506C), Office of Pesticide Programs, Environmental Protection Agency, 
401 M St., SW., Washington, DC 20460. In person, bring copy of 
objections and hearing requests to: Rm. 1132, CM #2, 1921 Jefferson 
Davis Highway, Arlington, VA 22202.
    A copy of objections and hearing requests filed with the Hearing 
Clerk may also be submitted electronically to the OPP by sending 
electronic mail (e-mail) to: <a href="/cdn-cgi/l/email-protection#026d72722f666d61696776426772636f636b6e2c6772632c656d74"><span class="__cf_email__" data-cfemail="4b243b3b662f2428202e3f0b2e3b2a262a2227652e3b2a652c243d">[email protected]</span></a>. Copies of 
objections and hearing requests must be submitted as an ASCII file 
avoiding the use of special characters and any form of encryption. 
Copies of objections and hearing requests will also be accepted on 
disks in WordPerfect in 5.1 file format or ASCII file format. All 
copies of objections and hearing requests in electronic form must be 
identified by the docket control number [OPP-300467; PP 0E3909, 2E4052, 
2E4065, 2E4092, and 3E4162]. No Confidential Business Information (CBI) 
should be submitted through e-mail. Electronic copies of objections and 
hearing requests on this rule may be filed online at many Federal 
Depository Libraries. Additional information on electronic submissions 
can be found in Unit IV. of this document.

FOR FURTHER INFORMATION CONTACT: By mail: Hoyt L. Jamerson, 
Registration Division (7505W), Office of Pesticide Programs, 
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460. 
Office location, telephone number and e-mail address: Sixth Floor, 
Crystal Station #1, 2800 Jefferson Davis Highway, Arlington, VA 22202, 
(703) 308-8783, e-mail:<a href="/cdn-cgi/l/email-protection#a9c3c8c4ccdbdac6c787c1c6d0dde9ccd9c8c4c8c0c587ccd9c887cec6df"><span class="__cf_email__" data-cfemail="85efe4e8e0f7f6eaebabedeafcf1c5e0f5e4e8e4ece9abe0f5e4abe2eaf3">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: In the Federal Register of January 8, 1997 
(62 FR 1114)(FRL-5582-6), EPA issued a notice pursuant to section 408 
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a, 
announcing the filing of amendments to pesticide petitions (PP) for 
tolerances by the Interregional Research Project No. 4 (IR-4), New 
Jersey Agricultural Experiment Station, P.O. Box 231, Rutgers 
University, New Brunswick, NJ 08903. This notice included a summary of 
the petitions prepared by BASF Corporation, the registrant. There were 
no comments received in response to the notice of filing. The amended 
petitions requested that 40 CFR 180.412 be amended by extending the 
effective dates to expire on December 31, 1998, for the time-limited 
tolerances established for combined residues of the herbicide 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 asparagus at 4.0 parts per 
million (ppm), carrot at 1.0 ppm, cranberry and endive at 2.0 ppm, and 
peppermint and spearmint at 30.0 ppm. Registration for use of 
sethoxydim on endive is limited to Florida based on the geographical 
representation of the residue data submitted. Additional residue data 
will be required to expand the area of usage. Persons seeking 
geographically broader registration should contact the Agency's 
Registration Division at the address provided above.
    These tolerances were established as time-limited tolerances since 
an acceptable carcinogenicity study is needed in one rodent species. A 
repeat chronic feeding/carcinogenicity study in rats was submitted to 
EPA in November of 1995 and is awaiting review. The Agency will 
reassess sethoxydim tolerances based on the outcome of the rat chronic 
feeding/carcinogenicity study and, if appropriate, will establish 
permanent tolerances for asparagus, carrot, cranberry, endive, 
peppermint and spearmint.

I. Risk Assessment and Statutory Findings

    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) 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, but does not include 
occupational exposure. Section 408(b)(2)(C) 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....''

A. Method of Determining Risks

    Dietary exposure to residues of a pesticide in a food commodity are 
estimated by multiplying the average daily consumption of the food 
forms of that commodity by the tolerance level or the anticipated 
pesticide residue level. The Theoretical Maximum Residue Contribution 
(TMRC) is an estimate of the level of residues consumed daily if each 
food item contained pesticide residues equal to the tolerance. The TMRC 
is a ``worst case'' estimate since it is based on the assumptions that 
food contains pesticide residues at the tolerance level and that 100 
percent of the crop is treated by pesticides that have established 
tolerances. If the TMRC exceeds the Reference Dose (RfD) or poses a 
lifetime cancer risk that is greater than approximately one in a 
million, EPA attempts to derive a more accurate exposure estimate for 
the pesticide by evaluating additional types of information 
(anticipated residue data and/or percent of crop treated data) which 
show, generally, that pesticide residues in most foods when they are 
eaten are well below established tolerances and that the total acreages 
for all crops with established tolerances are seldom treated with the 
pesticide.
    The RfD is assumed to be the exposure at or below which daily 
aggregate exposure over a lifetime will not pose an appreciable risk to 
human health. To assure the adequacy of the RfD, the Agency uses an 
uncertainty factor in deriving it. The factor is usually 100, based on 
the assumption that certain segments of the human population could be 
as much as 100 times more sensitive than the species represented by the 
toxicology data. The aggregate daily exposure to a pesticide residue at 
or below the RfD (expressed as l00 percent of the RfD) is generally 
considered acceptable by EPA.
    If the pesticide is determined to be a human carcinogen, the 
toxicological end-point must be determined based on the nature of the 
carcinogenic response and a knowledge of its mode of action. The Agency 
uses a weight of evidence approach in classifying the potential of the 
pesticide as a human carcinogen.
    In addition to assessing long-term, chronic exposure to pesticide 
residues in food, the Agency also evaluates single-day or single event, 
acute exposure. Acute dietary exposure to residues of a pesticide in a 
food commodity is estimated by multiplying individual, single-day 
consumption estimates of that food by the tolerance level or the 
anticipated pesticide residue level. Each individual's daily exposure 
to a pesticide is the sum of the

[[Page 17737]]

food commodities that individual consumed on that given day multiplied 
by the residue assumed to be present on each food commodity consumed. 
Using this method, a distribution of possible daily exposures for a 
given population is established.
    From this distribution, an upper end estimate of exposure is chosen 
and compared to the most sensitive no-observed-effect level (NOEL) from 
studies relating to the toxicological effect of acute concern (usually 
developmental toxicity or neurotoxicity) to derive a Margin of Exposure 
(MOE). The MOE is a measure of the level of safety that exists between 
the estimated exposure to a highly exposed individual and the level 
below which effects were observed in the available toxicological 
studies.

B. Toxicological Profile

    1. A 1-year feeding study with dogs fed diets containing 0, 8.86/
9.41, 17.5/19.9, and 110/129 milligrams per kilogram per day (mg/kg/
day) (males/females) with a NOEL of 8.86/9.41 mg/kg/day (males/females) 
based on equivocal anemia in male dogs at the 17.5-mg/kg/day dose 
level.
    2. A 2-year chronic feeding/carcinogenicity study with mice fed 
diets containing 0, 40, 120, 360, and 1,080 ppm (equivalent to 0, 6, 
18, 54, and 162 mg/kg/day) with a systemic NOEL of 120 ppm (18 mg/kg/
day) based on non-neoplastic liver lesions in male mice at the 360 ppm 
(54 mg/kg/day) dose level. There were no carcinogenic effects observed 
under the conditions of the study. The maximum tolerated dose (MTD) was 
not achieved in female mice.
    3. A 2-year chronic feeding/carcinogenic study with rats fed diets 
containing 0, 2, 6, and 18 mg/kg/day with a systemic NOEL greater than 
or equal to 18 mg/kg/day (highest dose tested). There were no 
carcinogenic effects observed under the conditions of the study. This 
study was reviewed under current guidelines and was found to be 
unacceptable because the doses used were insufficient to induce a toxic 
response and an MTD was not achieved.
    4. A second chronic feeding/carcinogenic study with rats fed diets 
containing 0, 360, and 1,080 ppm (equivalent to 18.2/23.0, and 55.9/
71.8 mg/kg/day (males/females). The dose levels were too low to elicit 
a toxic response in the test animals and failed to achieve an MTD or 
define a lowest effect level (LEL). Slight decreases in body weight in 
rats at the 1,080-ppm dose level, although not biologically 
significant, support a free-standing no-observed-adverse-effect-level 
(NOAEL) of 1,080 ppm (55.9/71.8 mg/kg/day (males/females)). There were 
no carcinogenic effects observed under the conditions of the study.
    5. A developmental toxicity study in rats fed dosages of 0, 50, 
180, 650, and 1,000 mg/kg/day with a maternal NOAEL of 180 mg/kg/day 
and a maternal LEL of 650 mg/kg/day (irregular gait, decreased 
activity, excessive salivation, and anogenital staining); and a 
developmental NOAEL of 180 mg/kg/day and a developmental LEL of 650 mg/
kg/day (21 to 22 percent 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).
    6. A developmental toxicity study in rabbits fed doses of 0, 80, 
160, 320, and 400 mg/kg/day with a maternal NOEL of 320 mg/kg/day and a 
maternal lowest observed effect level (LOEL) of 400 mg/kg/day (37 
percent reduction in body weight gain without significant differences 
in group mean body weights and decreased food consumption during 
dosing); and a developmental NOEL greater than 400 mg/kg/day (highest 
dose tested).
    7. A 2-generation reproduction study with rats fed diets containing 
0, 150, 600, and 3,000 ppm (approximately 0, 7.5, 30, and 150 mg/kg/
day) with no reproductive effects observed under the conditions of the 
study.
    8. Mutagenicity studies including: Ames assays were negative for 
gene mutation in Salmonella typhimurium strains TA98, TA100, TA1535, 
and TA1537, with and without metabolic activity; a Chinese hamster bone 
marrow cytogenetic assay was negative for structural chromosomal 
aberrations at doses up to 5,000 mg/kg in Chinese hamster bone marrow 
cells in vivo; and recombinant assays and forward mutations tests in 
Bacillus subtilis, Escherichia coli, and S. typhimurium were all 
negative for genotoxic effects at concentrations of greater than or 
equal to 100 percent.
    9. In a rat metabolism study, excretion was extremely rapid and 
tissue accumulation was negligible.

C. Toxicological Endpoints

    1. Dietary-- i. Chronic risk. The RfD for sethoxydim is calculated 
at 0.09 milligrams per kilogram of body weight per day (mg/kg/ bwt/day. 
The RfD is based on a NOEL of 8.86 mg/kg/day from a 1-year feeding 
study in dogs and an uncertainty factor of 100. This study demonstrated 
equivocal anemia in male dogs at the LOEL of 17.5 mg/kg/day.
    ii. Acute risk. EPA has determined that an NOEL of 180 mg/kg/day 
from a developmental toxicity study in rats should be used to assess 
acute dietary risk. Decreased fetal weights, filamentous tail, lack of 
tail, and delayed ossification were observed at the LOEL of 650 mg/kg/
day. The population of concern for this risk assessment are females 13+ 
years old.
    iii. Cancer risk. EPA has not fully determined the carcinogenic 
potential of sethoxydim. No positive tumor findings have been reported 
at this time in the evaluations of rat or mouse carcinogenicity 
studies. A repeat carcinogenicity study in rats was submitted by the 
registrant and is under evaluation by EPA. There was no reported 
carcinogenicity in the repeat rat study.
    2. Non-dietary. i.  Short- and intermediate-term risk. A risk 
assessment is not needed since no effects were observed in a 21-day 
dermal toxicity study in rabbits at the highest dose tested (1,000 mg/
kg/day) or in a developmental toxicity study in rabbits at the highest 
dose tested (400 mg/kg/day).
    ii. Chronic risk. Chronic risk estimates are not required since 
non-dietary (occupational/residential) exposure will not be chronic.

D. Aggregate Exposures and Risks

    1. From food. Food exposure to sethoxydim will be from ingestion of 
raw and processed agricultural commodities, as listed in 40 CFR 180.412 
and 185.2800. The existing sethoxydim tolerances (published, including 
the current time-limited tolerances) result in a TMRC that is 
equivalent to the following percentages of the RfD:

------------------------------------------------------------------------
                                                                        
------------------------------------------------------------------------
              U.S Population                36%                         
     Non-Nursing Infants (<1 year old)      61%                         
        Children (1 to 6 years old)         72%                         
------------------------------------------------------------------------

    The chronic dietary risk assessment used conservative assumptions 
resulting in risk estimates as high as 72% of the reference dose. 
Actual risks using more realistic assumptions would likely result in 
significantly lower risk estimates.
    The acute dietary risk assessment resulted in a MOE of 1,200 for 
females (13+ years old), the population of concern. The assumptions in 
this assessment were: (1) All tolerance level residues, (2) 100% crop 
treated, (3) no mixing of commodities, and (4) all foods consumed in a 
day by a person had tolerance level residues. These

[[Page 17738]]

assumptions are extremely conservative; risk assessment using more 
realistic assumptions would result in an estimated MOE significantly 
greater than 1,200.
    2. From drinking water. There is presently no established Maximum 
Concentration Level (MCL) for residues of sethoxydim in drinking water, 
and no health advisory levels for sethoxydim in drinking water have 
been established. Available monitoring studies, however, indicate that 
sethoxydim residues may migrate to ground water and surface water. In 
addition, the available data are inadequate to determine whether 
residues of the degradates of sethoxydim are likely to occur in water. 
Therefore, assessments of the risks posed to human health from exposure 
to potential sethoxydim residues in drinking water was conducted.
    The data used to estimate exposure in water wells are from one 
study conducted in Missouri involving 40 rural domestic drinking water 
wells and 25 public supply drinking water wells. All of the available 
monitoring data show nondetectable residues of sethoxydim. Therefore, 
to estimate sethoxydim exposure for the purposes of exposure and risk 
assessment, a value equal to one-half of the limit of detection for the 
analytical methods was used to determine sethoxydim residues in the 
drinking water samples. Samples from the rural domestic drinking water 
wells and the public supply drinking water wells were analyzed with 
different analytical methods with different limits of detection (0.2 
parts per billion (ppb) and 2 ppb, respectively). This risk assessment 
assumes exposure to be at 1 ppb based on one-half of the higher limit 
of detection (2 ppb). Exposure and risk was also estimated based on the 
highest sethoxydim residues (42 ppb) detected in ground water.
    Exposures and risks to residues of sethoxydim in drinking water 
were calculated using the following formulas:
    Adults (male): Exposure = (chemical concentration in micrograms 
(<greek-m>g)/liter (L) in consumed water)  x  (l0<SUP>-3</SUP> mg/
micrograms (<greek-m>g)) divided by (70 kg body weight)  x  (2 L 
water consumed/day).

    Children (1 to 6 years): Exposure = (chemical concentration in 
<greek-m>g/L in consumed water)  x  (l0<SUP>-3</SUP> mg/<greek-m>g)) 
divided by (10 kg body weight)  x  (1 L water consumed/day).

    i. Chronic exposures and risks from drinking water. a. Adult (male) 
exposure (based on estimated residues in public water wells) = 
(1<greek-m>g/L)  x  (10<SUP>-3</SUP> mg/<greek-m>g) divided by (70 kg 
body weight)  x  (2 L/day) = 2.85  x  10<SUP>-5</SUP> mg/kg/day, which 
accounts for < 1% of the RfD.
    b. Adult (male) exposure (based on highest concentration detected 
in ground water) = (42 <greek-m>g/L)  x  (10<SUP>-3</SUP> mg/
<greek-m>g) divided by (70 kg body weight)  x  (2 L/day) = 1.2  x  
10<SUP>-3</SUP> mg/kg/day, which accounts for 1% of the RfD.
    c. Children (1 to 6 years old) exposure (based on estimated 
residues in public water wells) = (1 <greek-m>g)/L)  x  
(10<SUP>-3</SUP> mg/<greek-m>g) divided by (10 kg body weight)  x  (1 
L/day) = 1  x  10<SUP>-4</SUP> mg/kg/day, which accounts for < 1% of 
the RfD.
    d. Children (1 to 6 years old) exposure (based on highest 
concentration detected in ground water) = (42 <greek-m>g)/L)  x  
(10<SUP>-3</SUP> mg/<greek-m>g) divided by (10 kg body weight)  x  (1 
L/day) = 4.2  x  10<SUP>-3</SUP> mg/kg/day, which accounts for 5% of 
the RfD.
    ii. Acute risk from drinking water. a. Acute risk from residues of 
sethoxydim in drinking water were calculated as follows: Exposure = 
(chemical concentration in <greek-m>g)/L in consumed water)  x  
(10<SUP>-3</SUP> mg/<greek-m>g) divided by (kg body weight)  x  (liters 
(L) of water consumed/day).
    b. Adult (female) exposure (based on highest concentration of 
sethoxydim detected in ground water) = (42 <greek-m>g)/L)  x  
(10<SUP>-3</SUP> mg/<greek-m>g) divided by (60 kg body weight)  x  (2 
L/day) = 1.4  x  10<SUP>-3</SUP> <greek-m>g)/kg/day.
    c. Children (1 to 6 years old) exposure (based on highest 
concentration of sethoxydim detected in ground water) = (42 
<greek-m>g)/L)  x  (10<SUP>-3</SUP> mg/<greek-m>g) divided by 10 kg 
body weight)  x  (1 L/day) = 4.2  x  10<SUP>-3</SUP>.
    d. Margins of Exposure were calculated based on the above exposure 
estimates as follows:
    (i) For female adults consuming water containing 42 <greek-m>g/L of 
sethoxydim the MOE is equal to 180/1.4  x  10<SUP>-3</SUP> = 130,000.
    (ii) For children (1 to 6 years old) consuming water containing 42 
<greek-m>g)/L of sethoxydim the MOE is equal to 180/1.4  x  
10<SUP>-3</SUP> = 43,000.
    3. From non-dietary (residential) exposure. Sethoxydim is currently 
registered for use by homeowners on the following residential use 
sites: vegetables, fruits, flowers, shrubs, trees, and bedding plants. 
However, this risk assessment is not required.
    4. Cumulative exposure to substances with common mechanism of 
toxicity. Section 408(b)(2)(D)(v) requires that, when considering 
whether to establish, modify, or revoke a tolerance, the Agency 
consider ``available information'' concerning the cumulative effects of 
a particular pesticide's residues and ``other substances that have a 
common mechanism of toxicity.'' The Agency believes that ``available 
information'' in this context might include not only toxicity, 
chemistry, and exposure data, but also scientific policies and 
methodologies for understanding common mechanisms of toxicity and 
conducting cumulative risk assessments. For most pesticides, although 
the Agency has some information in its files that may turn out to be 
helpful in eventually determining whether a pesticide shares a common 
mechanism of toxicity with any other substances, EPA does not at this 
time have the methodologies to resolve the complex scientific issues 
concerning common mechanism of toxicity in a meaningful way. EPA has 
begun a pilot process to study this issue further through the 
examination of particular classes of pesticides. The Agency hopes that 
the results of this pilot process will increase the Agency's scientific 
understanding of this question such that EPA will be able to develop 
and apply scientific principles for better determining which chemicals 
have a common mechanism of toxicity and evaluating the cumulative 
effects of such chemicals. The Agency anticipates, however, that even 
as its understanding of the science of common mechanisms increases, 
decisions on specific classes of chemicals will be heavily dependent on 
chemical specific data, much of which may not be presently available.
    Although at present the Agency does not know how to apply the 
information in its files concerning common mechanism issues to most 
risk assessments, there are pesticides as to which the common mechanism 
issues can be resolved. These pesticides include pesticides that are 
toxicologically dissimilar to existing chemical substances (in which 
case the Agency can conclude that it is unlikely that a pesticide 
shares a common mechanism of activity with other substances) and 
pesticides that produce a common toxic metabolite (in which case common 
mechanism of activity will be assumed).
    EPA does not have, at this time, available data to determine 
whether sethoxydim has a common mechanism of toxicity with other 
substances or how to include this pesticide in a cumulative risk 
assessment. Unlike other pesticides for which EPA has followed a 
cumulative risk approach based on a common mechanism of toxicity, 
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 subtances.

E. Determination of Safety for Infants and Children

    FFDCA section 408 provides that EPA shall apply an additional 
tenfold MOE (safety) for infants and children in the

[[Page 17739]]

case of threshold effects to account for pre-and post-natal toxicity 
and the completeness of the database unless EPA determines that a 
different MOE (safety) will be safe for infants and children. Margins 
of exposure (safety) are often referred to as uncertainty (safety) 
factors. EPA believes that reliable data support using the standard MOE 
(usually 100x for combined inter- and intra-species variability)) and 
not the additional tenfold MOE when EPA has a complete data base under 
existing guidelines and when the severity of the effect in infants or 
children or the potency or unusual toxic properties of a compound do 
not raise concerns regarding the adequacy of the standard MOE.
    The data base for sethoxydim realtive to pre- and post-natal 
toxicity is complete and is summarized as follows:
    1. Developmental toxicity studies. In the rat developmental 
toxicity study the maternal (systemic) NOEL is established at 180 mg/
kg/day, based on irregular gait, decreased activity, excessive 
salivation and anogenital staining at 650 mg/kg/day. The developmental 
(pup) NOEL is 180 mg/kg/day, based on decreased fetal weights, 
filamentous tail, lack of tail, and delayed-ossification at 650 mg/kg/
day.
    In the rabbit developmental toxicity study the maternal (systemic) 
NOEL is established at 320 mg/kg/day, based on a 37% reduction in body 
weight gain without significant differences in group mean body weights 
and food consumption at 400 mg/kg/day. The developmental (pup) NOEL is 
<gr-thn-eq>400 mg/kg/day (highest dose tested).
    2. Reproduction studies. In a 2-generation reproduction study in 
the rat the maternal/reproductive NOEL is approximately 150 mg/kg/day, 
the highest dose tested. This study did not fully meet the requirements 
of achieving toxicity as defined by the Pesticide Assessment Guidelines 
( OPPTS-870); however, this study is considered usable for regulatory 
purposes and a freestanding NOEL is established at approximately 150 
mg/kg/day (LOEL not established). There were no indications of 
toxicity, dose-related effects on fertility, or difficult deliveries in 
either parental generation.
    Conclusions. The toxicological database for evaluating pre- and 
postnatal toxicity for sethoxydim is complete. Available data indicate 
that no developmental toxicity was observed in the rabbit study at the 
highest dose tested (400 mg/kg/day). Maternal toxicity was observed in 
the rabbit at the highest dose tested and consisted of significant 
reductions in body weight gain and food consumption. In the rat 
developmental study developmental toxicity was observed in the presence 
of significant maternal toxicity at a high dose level (650 mg/kg/day). 
There was no parental or reproductive toxicity observed in a 
multigeneration reproduction study at doses up to 150 mg/kg/day 
(highest dose tested). These data taken together suggest minimal 
concern for developmental or reproductive toxicity and do not indicate 
any increased pre- or postnatal sensitivity; and no additional 
uncertainty factor for increased sensitivity in infants and children is 
appropriate. Therefore, EPA concludes that reliable data support using 
a hundredfold uncertainty factor and that uncertainty factor will 
protect the safety of infants and children without an additional 
tenfold uncertainty factor. Based on very conservative exposure 
assumptions, EPA concludes that aggregate exposure to children and 
infants will not exceed the RfD. EPA concludes that there is a 
reasonable certainty that no harm will result to infants and children 
from aggregate exposure.

F. Other Considerations

    1. Endocrine effects. An evaluation of the potential effects on the 
endocrine systems of mammals has not been determined; however, no 
evidence of such effects were reported in the chronic toxicology 
studies described above. There were no observed pathology of the 
endocrine organs in these studies. There is no evidence at this time 
that sethoxydim causes endocrine effects.
    2. Metabolism in plants and animals. The metabolism of sethoxydim 
in plants and animals is adequately understood for the purposes of 
these tolerances. The residues of concern in plants and animals are 
sethoxydim and its metabolites containing the 2-cyclohexen-l-one moiety 
calculated as sethoxydim, as specified in 40 CFR 180.412.
    3. Secondary residues. Carrot culls are the only animal feed items 
associated with these uses. Secondary residues in animal commodities 
are not expected to exceed existing tolerances as a result of this use.
    4.  Analytical method. There is a practical analytical method for 
detecting and measuring levels of sethoxydim and its metabolites in or 
on food with a limit of detection that allows monitoring of food with 
residues at or above the levels set in this tolerance. Method 30G, is 
available in PAM, Vol II to enforce the tolerance expression. Method 
30G is a capillary gas chromatography method which uses flame 
photometric detection in the sulfur mode and determines total residues 
of sethoxydim and its metabolites containing the 2-cyclohexen-l-one 
moiety.
    5. International tolerances. There are no Codex, Canadian, or 
Mexican Maximum Residue Levels or tolerances established for sethoxydim 
in/on asparagus, endive, carrots, cranberry, or mint.

II. Summary of Findings

    Both the chronic and acute dietary risk assessments are 
conservative and represent overestimates of risk because they assume 
tolerance level residues and 100% crop treated for all commodities 
having sethoxydim tolerances. Refinement of dietary exposure estimates 
using percent crop treated data and/or anticipated residue data would 
result in significantly lower dietary exposure estimates. Aggregate 
chronic risks are estimated at 37% of the RfD (36% for food and 1% for 
water) for the general population, and 77% of the RfD (72% for food and 
5% for water for children (1 to 6 years old)). For acute dietary risks, 
the calculated MOE's for the population subgroup of concern (females 
13+ years old) is 1,200 from residues of sethoxydim in food and > 
130,000 for residues in drinking water. The aggregate MOE is also 
1,200.
    Based on the information cited above, the Agency has determined 
that the establishment of the time-limited tolerances by amending 40 
CFR 180.412 will be safe; therefore, the time-limited tolerances are 
established as set forth below.
    In addition to the time-limited tolerances being amended, since for 
purposes of establishing tolerances FQPA has eliminated all 
distinctions between raw and processed food, EPA is combining the 
tolerances that now appear in Secs. 185.2800 and 186.2800 with the 
tolerances in Sec. 180.412 and is eliminating Secs. 185.2800 and 
186.2800.

III. Objections and Hearing Requests

    The new FFDCA section 408(g) provides essentially the same process 
for persons to ``object'' to a tolerance regulation issued by EPA under 
new section 408(e) and (1)(6) as was provided in the old section 408 
and in section 409. However, the period for filing objections is 60 
days, rather than 30 days. EPA currently has procedural regulations 
which governs the submission of objections and hearing requests. These 
regulations will require some modification to reflect the new law. 
However, until those modifications can be made, EPA will continue to 
use those procedural regulations with

[[Page 17740]]

appropriate adjustments to reflect the new law.
    Any person may, by June 10, 1997 file written objections to any 
aspect of this regulation and may also request a hearing on those 
objections. Objections and hearing requests must be filed with the 
Hearing Clerk, at the address given above (40 CFR 178.20). A copy of 
the objections and/or hearing requests filed with the Hearing Clerk 
should be submitted to the OPP docket for this rulemaking. The 
objections submitted must specify the provisions of the regulation 
deemed objectionable and the grounds for the objections (40 CFR 
178.25). Each objection must be accompanied by the fee prescribed by 40 
CFR 180.33(i). If a hearing is requested, the objections must include a 
statement of the factual issue(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). 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 
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 issue(s) in the manner sought by the requestor would be 
adequate to justify the action requested (40 CFR 178.32). Information 
submitted in connection with an objection or hearing request may be 
claimed confidential by marking any part or all of that information as 
Confidential Business Information (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.

IV. Public Docket

    A record has been established for this rulemaking under docket 
number [OPP-300467; PP 0E3909, 2E4052, 2E4065, 2E4092, and 3E4162]. A 
public version of this record, which does not include any information 
claimed as CBI, is available for inspection from 8:30 a.m. to 4 p.m., 
Monday through Friday,excluding legal holidays. The public record is 
located in Room 1132 of the Public Response and Program Resources 
Branch, Field Operations Division (7506C), Office of Pesticide 
Programs, Environmental Protection Agency, Crystal Mall #2, 1921 
Jefferson Davis Highway, Arlington, VA.
    The official record for this rulemaking, as well as the public 
version, as described above, is kept in paper form. Accordingly, in the 
event there are objections and hearing requests, EPA will transfer any 
copies of objections and hearing requests received electronically into 
printed, paper form as they are received and will place the paper 
copies in the official rulemaking record. The official rulemaking 
record is the paper record maintained at the address in ``ADDRESSES'' 
at the beginning of this document.

V. Regulatory Assessment Requirements

    Under Executive Order 12866 (58 FR 51735, Oct. 4, 1993), this 
action is not a ``significant regulatory action'' and since this action 
does not impose any information collection requirements subject to 
approval under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq., it 
is not subject to review by the Office of Management and Budget. In 
addition, this action does not impose any enforceable duty, or contain 
any ``unfunded mandates'' as described in Title II of the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4), or require prior 
consultation as specified by Executive Order 12875 (58 FR 58093, 
October 28, l993), or special considerations as required by Executive 
Order 12898 (59 FR 7629, February 16, l994).
    Because tolerances established on the basis of a petition under 
section 408(d) of FFDCA do not require issuance of a proposed rule, the 
regulatory flexibility analysis requirements of the Regulatory 
Flexibility Act (RFA), 5 U.S.C. 604(a), do not apply. Prior to the 
recent amendment of the FFDCA, EPA had treated such rulemakings as 
subject to the RFA; however, the amendments to the FFDCA clarify that 
no proposal is required for such rulemakings and hence that the RFA is 
inapplicable. Nonetheless, the Agency has previously assessed whether 
establishing tolerances or exemptions from tolerance, raising tolerance 
levels, or expanding exemptions adversely impact small entities and 
concluded, as a generic matter, that there is no adverse impact. (46 FR 
24950) (May 4, 1981).
    Pursuant to 5 U.S.C. 801(a)(1)(A), EPA submitted 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 
General Accounting Office prior to publication of the rule in today's 
Federal Register. This rule is not a major rule as defined by 5 U.S.C. 
804(2).

List of Subjects

40 CFR Part 180

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Pesticides and pests, Reporting and 
recordkeeping requirements.

40 CFR Part 185

    Environmental protection, Food additives, Pesticides and pests.

40 CFR Part 186

    Environmental protection, Animal feeds, Pesticides and pests.

    Dated: April 4, 1997.

Penelope A. Fenner-Crisp,
Acting Director, Office of Pesticide Programs.
    Therefore, 40 CFR chapter I is amended as follows:

PART 180-- [AMENDED]

    1. In part 180:
    a. The authority citation for part 180 continues to read as 
follows:
    Authority: 21 U.S.C. 346a and 371.

    b. Section 180.412 is amended as follows:
    i. By revising the section heading to read as set forth below.
    ii. By revising paragraph (a).
    iii. In paragraph (b) by removing the text and by adding the 
heading ``Section 18 emergency exemptions.'', and reserving it.
    iv. By revising paragraph (c).
    v. By removing the text of paragraph (d), adding a heading entitled 
``Indirect and inadvertent residues.'' and reserving it.


Sec. 180.412   Sethoxydim; tolerances for residues.

    (a) General. Tolerances are established for combined residues of 
the herbicide 2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-
hydroxy-2-cyclohexen-1-one (CAS Reg. No. 74051-80-2) and its 
metabolites containing the 2-cyclohexen-1-one moiety (calculated as the 
herbicide) in or on the following commodities:

[[Page 17741]]



                                                                        
------------------------------------------------------------------------
                                Parts per                               
          Commodity              million     Expiration/Revocation Date 
------------------------------------------------------------------------
Alfalfa, forage..............    40.0                               None
Alfalfa, hay.................    40.0                               None
Almond hulls.................     2.0                               None
Apple pomace, wet and dry....     0.8                               None
Asparagus....................     4.0                  December 31, 1998
Beans, dry...................    20.0                               None
Beans, forage................    10.0                               None
Beans, hay...................    50.0                               None
Beans, succulent.............     5.0                               None
Blueberries..................     4.0                               None
Brassica leafy vegetables....     5.0                               None
Bulb vegetables..............     1.0                               None
Canola/rapeseed, meal........    40.0                               None
Canola/rapeseed..............    35.0                               None
Carrot.......................     1.0                  December 31, 1998
Cattle, fat..................     0.2                               None
Cattle, mbyp.................     0.2                               None
Cattle, meat.................     0.2                               None
Celery.......................     1.0                               None
Citrus fruits................     0.5                               None
Citrus molasses..............     1.5                               None
Citrus pulp, dried...........     1.5                               None
Clover, forage...............    35.0                               None
Clover, hay..................    50.0                               None
Cottonseed soapstock.........    15                                 None
Corn, field, grain...........     0.5                               None
Corn fodder..................     2.5                               None
Corn forage..................     2.0                               None
Corn, sweet (K+CWHR).........     0.2                               None
Cranberry....................     2.0                  December 31, 1998
Cottonseed...................     5.0                               None
Cucurbits vegetables.........     4.0                               None
Eggs.........................     2.0                               None
Flaxseed.....................     5.0                               None
Flaxseed meal................     7                                 None
Flax straw...................     2.0                               None
Fruiting vegetables..........     4.0                               None
Goats, fat...................     0.2                               None
Goats, mbyp..................     0.2                               None
Goats, meat..................     0.2                               None
Grape pomace, wet and dry....     6.0                               None
Grapes.......................     0.2                               None
Hogs, fat....................     0.2                               None
Hogs, mbyp...................     0.2                               None
Hogs, meat...................     0.2                               None
Horses, fat..................     0.2                               None
Horses, mbyp.................     0.2                               None
Horses, meat.................     0.2                               None
Lentils......................    30.0                               None
Lettuce, head................     1.0                               None
Lettuce, leaf................     2.0                               None
Milk.........................     0.05 (N)                          None
Peanuts......................    25.0                               None
Peanuts, hull................     5.0                               None
Peanut soapstock.............    75.0                               None
Peas, dry....................    40.0                               None
Peas, forage.................    20.0                               None
Peas, hay....................    40.0                               None
Peas, succulent..............    10.0                               None
Peppermint, tops (stems and                                             
 leaves).....................    30.0                  December 31, 1998
Pome fruits..................     0.2                               None
Potatoes.....................     4.0                               None
Potato flakes................     8.0                               None
Potato granules..............     8.0                               None
Potato waste, processed (wet                                            
 and dry)....................     8.0                               None
Poultry, fat.................     0.2                               None
Poultry, mbyp................     2.0                               None
Poultry, meat................     0.2                               None
Raisins......................     1.0                               None
Raisin waste.................     1.0                               None
Raspberries..................     5.0                               None

[[Page 17742]]

                                                                        
Sheep, fat...................     0.2                               None
Sheep, mbyp..................     0.2                               None
Sheep, meat..................     0.2                               None
Soybean, hay.................    10.0                               None
Soybeans.....................    10.0                               None
Spearmint, tops (stems and                                              
 leaves).....................    30.0                  December 31, 1998
Spinach......................     4.0                               None
Strawberries.................    10.0                               None
Sugar beet molasses..........    10.0                               None
Sugar beet, roots............     1.0                               None
Sugar beet, tops.............     3.0                               None
Sunflower meal...............    20.0                               None
Sunflower seeds..............     7.0                               None
Sweet potato.................     4.0                               None
Tomato pomace, dried.........    12.0                               None
Tomato products, concentrated    24                                 None
Tree nuts....................     0.2                               None
------------------------------------------------------------------------

    (b) Section 18 emergency exemptions. [Reserved]
    (c) Tolerances with regional registration. Tolerances with regional 
registration, as defined in Sec. 180.1(n), are established for the 
combined residues of the herbicide 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 the following commodities:

                                                                        
------------------------------------------------------------------------
                                Parts per                               
          Commodity              million     Expiration/Revocation Date 
------------------------------------------------------------------------
Artichokes...................     3.0                               None
Endive.......................     2.0                  December 31, 1998
Rhubarb......................     0.3                               None
------------------------------------------------------------------------

    (d)  Indirect and inadvertent residues.[Reserved]

PART 185--[AMENDED]

    2. In part 185:
    a. The authority citation for part 185 continues to read as 
follows:
    Authority: 21 U.S.C. 346a and 348.

Sec. 185.2800 [Removed]

    b. Section 185.2800 is removed.

PART 186--[AMENDED]

    3. In part 186:
    a. The authority citation for part 186 continues to read as 
follows:
    Authority: 21 U.S.C.342, 348, and 701.

Sec. 186.2800 [Removed]

    b. Section 186.2800 is removed.

[FR Doc. 97-9374 Filed 4-10-97; 8:45 am]
BILLING CODE 6560-50-F


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