[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: opp-docket@epamail.epa.gov. 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:jamerson.hoyt@epamail.epa.gov.
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:
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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="">g)/liter (L) in consumed water) x (l0-3 mg/
micrograms (g)) divided by (70 kg body weight) x (2 L
water consumed/day).
Children (1 to 6 years): Exposure = (chemical concentration in
g/L in consumed water) x (l0-3 mg/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) =
(1g/L) x (10-3 mg/g) divided by (70 kg
body weight) x (2 L/day) = 2.85 x 10-5 mg/kg/day, which
accounts for < 1%="" of="" the="" rfd.="" b.="" adult="" (male)="" exposure="" (based="" on="" highest="" concentration="" detected="" in="" ground="" water)="(42">g/L) x (10-3 mg/
g) divided by (70 kg body weight) x (2 L/day) = 1.2 x
10-3 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 g)/L) x
(10-3 mg/g) divided by (10 kg body weight) x (1
L/day) = 1 x 10-4 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">g)/L) x
(10-3 mg/g) divided by (10 kg body weight) x (1
L/day) = 4.2 x 10-3 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 g)/L in consumed water) x
(10-3 mg/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 g)/L) x
(10-3 mg/g) divided by (60 kg body weight) x (2
L/day) = 1.4 x 10-3 g)/kg/day.
c. Children (1 to 6 years old) exposure (based on highest
concentration of sethoxydim detected in ground water) = (42
g)/L) x (10-3 mg/g) divided by 10 kg
body weight) x (1 L/day) = 4.2 x 10-3.
d. Margins of Exposure were calculated based on the above exposure
estimates as follows:
(i) For female adults consuming water containing 42 g/L of
sethoxydim the MOE is equal to 180/1.4 x 10-3 = 130,000.
(ii) For children (1 to 6 years old) consuming water containing 42
g)/L of sethoxydim the MOE is equal to 180/1.4 x
10-3 = 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
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
