[Federal Register Volume 62, Number 46 (Monday, March 10, 1997)]
[Rules and Regulations]
[Pages 10703-10708]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-5874]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300459; FRL-5591-9]
RIN AB-78
Sulfentrazone; Establishment of Tolerances
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This document establishes tolerances for residues of the
herbicide sulfentrazone (N-[2,4-dichloro-5-[4-(difluoromethyl)-4,5-
dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]phenyl]methanesulfonamide)
and its major metabolite 3-hydroxymethyl sulfentrazone (N-[2,4-
dichloro-5-[4-(difluoromethyl)-4,5-dihydro-3-hydroxymethyl-5-oxo-1H-
1,2,4-triazol-1-yl]phenyl]methanesulfonamide), in or on the raw
agricultural commodity soybean seed at 0.05 ppm and for combined
inadvertent residues of sulfentrazone, and its metabolites, 3-
hydroxymethyl sulfentrazone and 3-desmethyl sulfentrazone [N-[2,4-
dichloro-5-[4-(difluoromethyl)-4,5-dihydro-5-oxo-1H-1,2,4-triazol-l-
yl]phenyl]methanesulfonamide] in cereal grains (excluding sweet corn)
forage at 0.2 ppm, straw at 0.6 ppm, hay at 0.2 ppm, grain at 0.1 ppm,
stover at 0.1 ppm, bran at 0.15 ppm and hulls at 0.30 ppm. FMC
Corporation submitted a petition to EPA under the Federal Food, Drug
and Cosmetic Act as amended by the Food Quality Protection Act of l996
(Pub. L. 104-170) requesting the tolerances.
EFFECTIVE DATE: This regulation becomes effective March 10, 1997.
ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [PF-670/OPP-300459], may be submitted to:
Hearing Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M
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 Hwy., 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 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 PF-670/OPP-300459. 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.
FOR FURTHER INFORMATION CONTACT: By mail: Joanne I. Miller, Product
Manager (PM) 23, Registration Division (7505C), Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460. Office
location and telephone number: Rm. 237, CM #2, 1921 Jefferson Davis
Hwy., Arlington, VA 22202, (703)-305-6224; e-mail:
miller.joanne@epamail.epa.gov.
SUPPLEMENTARY INFORMATION: In the Federal Register of November 6, 1996
(60 FR 57420) (FRL-5571-4), EPA issued a notice pursuant to section
408(d) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C.
346a(d), announcing the filing of a pesticide tolerance petition by FMC
Corporation, 1735 Market Street, Philadelphia, PA 19103. The petition
requested to amend 40 CFR part 180 by establishing a tolerance for
residues of the herbicide sulfentrazone (N-[2,4-dichloro-5-[4-
(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]
phenyl]methanesulfona- mide) in or on raw agricultural commodity
soybean seed at 0.05 ppm and rotational crop tolerances in cereal
grains from 0.1 to 0.5 ppm. There were no comments received in response
to the notice of filing.
The data submitted in the petition and other relevant material have
been evaluated. The toxicology data listed below were considered in
support of these tolerances.
I. Toxicological Profile
1. A battery of acute toxicity studies placed technical
sulfentrazone in Toxicity Categories III and IV. No evidence of
sensitization was observed following dermal application in guinea pigs.
2. A 90-day subchronic toxicity study was conducted in rats, with
dietary intake levels of 0, 3.3, 6.7, 19.9, 65.8, 199.3, or 534.9 mg/
kg/day for males and 0, 4, 7.7, 23.1, 78.1, 230.5, or 404.3 milligrams/
kilograms/day (mg/kg/day) for females respectively. No Observed Effect
Levels (NOELs) of 19.9 mg/kg/day in males and 23.1 mg/kg/day in females
were based on clinical anemia.
3. A 90-day subchronic feeding study was conducted in mice by
dietary admix
[[Page 10704]]
at doses of 0, 10.3, 17.8, 60.0, 108.4, or 194.4 mg/kg/day for males
and 0, 13.9, 29.0, 79.8, 143.6, or 257.0 mg/kg/day for females,
respectively. NOELs of 60 mg/kg/day (males) and 79.8 mg/kg/day
(females) were based on decreases in body weights and/or gains;
decreased erythrocytes, hemoglobin and hematocrit values; and splenic
microscopic pathology.
4. In a 90-day subchronic feeding study in dogs administered by
dietary admix at doses of 0, 10, 28, or 57 mg/kg/day for males and 0,
10, 28, or 73 mg/kg/day for females, a NOEL of 28 mg/kg/day was
determined for both males and females based on decreases in hemoglobin
and hematocrit, elevated alkaline phosphatase levels, increased liver
weights and microscopic liver as well as splenic changes.
5. A 12-month feeding study in dogs was dosed at levels of 0.0,
9.9, 24.9, or 61.2 mg/kg/day for male dogs and 0.0, 10.4, 29.6, or 61.9
mg/kg/day for female dogs in the control through high-dose groups,
respectively, with a NOEL of 24.9 mg/kg/day for males and 29.6 mg/kg/
day for females based on hematology effects and microscopic liver
changes.
6. An 18-month feeding/carcinogenicity study in mice was conducted
with dietary intake of 0, 46.6, 93.9, 160.5, or 337.6 mg/kg/day for
males and 0, 58.0, 116.9, 198.0, or 407.1 mg/kg/day for females. A NOEL
of 93.9 mg/kg/day in males and 116.9 mg/kg/day in females was based on
decreases in hemoglobin and hematocrit. There were no treatment-related
increases in tumors of any kind observed at any dose level.
7. In a 24-month chronic feeding/oncogenicity study in rats at
dietary doses of 0, 24.3, 40.0, 82.8, or 123.5 mg/kg/day for males and
0, 20.0, 36.4, 67.0, or 124.7 mg/kg/day for females, an overall NOEL of
40.0 mg/kg/day in males and 36.4 mg/kg/day in females was based on
hematology effects and reduced body weights. There was no evidence of
an oncogenic response.
8. A prenatal oral developmental toxicity study in the rat with
dose levels at 25.0 or 50.0 mg/kg/day established a maternal NOEL of 25
mg/kg/day based on decreased body weight gain, increased spleen weight,
and microscopic changes in the spleen, and a fetal NOEL of 10 mg/kg/day
was based on fetal death, reduced body weights, and alterations in
skeletal development at higher doses.
9. A supplemental oral developmental toxicity study conducted in
rats at oral dose levels of 25.0 and 50.0 mg/kg/day to test for cardiac
effects at the request of the EPA, did not reveal any significant
effects on fetal cardiac development. The results of this study
confirmed the maternal and fetal findings of the previously-conducted
developmental study on sulfentrazone in rats and did not alter the
study conclusions.
10. In a dermal developmental study in the rat at doses of 0, 5,
25, 50, 100 and 250 mg/kg/day, a maternal (systemic) No Observed
Adverse Effect Level (NOAEL) was established at 250 mg/kg/day.
Significant treatment-related increases in the fetal and litter
incidences of incompletely ossified lumbar vertebral arches,
hypoplastic or wavy ribs, and incompletely ossified or nonossified
ischia or pubes occurred at the high-dose (250 mg/kg/day). An
additional significant increase in the high-dose fetal incidence of
variations in the sternebrae (incompletely ossified or unossified) was
not judged to be treatment-related. At 250 mg/kg/day, the mean numbers
of thoracic vertebral and rib ossification sites were significantly
decreased, a high-dose effect of treatment with sulfentrazone
consistent with the significant treatment-related hypoplasia observed
in the skeletal evaluation of the ribs. Therefore, the developmental
(fetal) Lowest Observed Effect Level (LOEL) is 250 mg/kg/day based on
decreased fetal body weight; increased incidences of fetal variations:
hypoplastic or wavy ribs, incompletely ossified lumbar vertebral
arches, and incompletely ossified ischia or pubes; and reduced number
of thoracic vertebral and rib ossification sites. The developmental
(fetal) NOEL is 100 mg/kg/day.
11. A developmental toxicity study in rabbits was conducted at
gavage dose levels of 0, 100, 250, or 375 mg/kg/day. Treatment-related
incidences of decreased feces and hematuria were noted at 250 mg/kg/day
or greater. In addition, at the 375 mg/kg/day dose level, five rabbits
aborted. Significant reductions in mean body weight change were
observed for the dosing period (GD 7- 19) and for the study duration
(GD 0-29, both before and after adjustment for gravid uterine weight)
at the 250 and 375 mg/kg/day dose levels. Therefore, the maternal
(systemic) LOEL is 250 mg/kg/day, based upon increased abortions,
clinical signs (hematuria and decreased feces), and reduced body weight
gain. The maternal (systemic) NOEL is 100 mg/kg/day. Skeletal
evaluation in fetuses revealed dose- and treatment-related findings at
the 375 mg/kg/day dose level. These included significant increases in
both the fetal and litter incidences of fused caudal vertebrae (a
malformation) and of partially fused nasal bones (a variation). In
addition, at 375 mg/kg/day, significant treatment-related reductions in
ossification site averages were observed for metacarpals and both fore-
and hindpaw phalanges. Therefore, the developmental (fetal) LOEL is 250
mg/kg/day, based upon increased resorptions, decreased live fetuses per
litter, and decreased fetal weight. The developmental (fetal) NOEL is
100 mg/kg/day.
12. A two-generation reproduction study in the rat at dietary
levels of 14, 33, or 46 mg/kg/day in males and 16, 40, or 56 mg/kg/day
in females established a NOEL for systemic and reproductive/
developmental parameters of 14 mg/kg/day for males and 16 mg/kg/day for
females. The LOEL for systemic and reproductive/development parameters
was 33 mg/kg/day for males and 40 mg/kg/day for females. Systemic
effects were comprised of decreased body weight gains, while
reproductive/developmental effect at the LOEL included degeneration
and/or atrophy in the testes, with epididymal sperm deficits, in the
second (F1) generation males. Male fertility in the F1 generation was
reduced at higher doses; litter size, pup survival, and pup body weight
for both generations were also effected at higher doses.
13. A supplemental two-generation rat reproduction study was
conducted at dietary intake levels of 50, 100, 200, or 500 ppm with a
NOEL for reproductive parameters of 200 ppm. This study confirmed the
reproductive/developmental effects observed in the first two-generation
reproductive toxicity study. It was the conclusion of the RfD/Peer
Review Committee that, under the conditions of the studies reviewed,
sulfentrazone caused developmental and reproductive toxicity. The
results of these studies elicited a high level of concern by the
Committee, since the developmental toxicity studies demonstrated
embryo/fetal toxicity at treatment levels that were not maternally
toxic, and significant toxic effects were observed primarily in the
second generation animals of the reproduction study. Because these
animals had been exposed to sulfentrazone in utero, the possibility
that the observed reproductive toxicity resulted from a developmental
and/or genotoxic mechanism was suggested.
14. A reverse gene mutation assay (salmonella typhimurium) yielded
negative results, both with and without metabolic activation.
15. A mouse lymphoma forward gene mutation assay yielded negative
results with equivocal results without activation.
[[Page 10705]]
16. A mouse micronucleus assay test was negative following
intraperitoneal injection of 340 mg/kg.
17. In an acute neurotoxicity study in rats at gavage doses of 0,
250, 750, or 2,000 mg/kg, a NOEL of 250 mg/kg and a LOEL of 750 mg/kg
were based upon increased incidences of clinical signs, Functional
Observation Battery (FOB) findings, and decreased motor activity which
were reversed by day 14 post-dose. There was no evidence of
neuropathology.
18. A 90-day subchronic neurotoxicity study in the rat was
conducted at dietary levels of 30, 150, or 265 mg/kg/day in males, and
37, 180, or 292 mg/kg/day in females, with a NOEL of 30 mg/kg/day in
males and 37 mg/kg/day in females. The LOEL was 150 mg/kg/day for males
and 180 mg/kg/day for females based on increased incidences of clinical
signs, decreased body weights, body weight gains, and food consumption
in females and increased motor activity in females at week 13. There
were no neurohistopathological effects on the peripheral or central
nervous system.
19. A metabolism study in rats indicated that approximately 84 to
104% of the orally administered dose of sulfentrazone was excreted in
the urine, and that the pooled urinary radioactivity consisted almost
entirely of 3-hydroxymethyl sulfentrazone. Pooled fecal radioactivity
showed that the major metabolite consisted of 3-hydroxymethyl-
sulfentrazone (1.26 to 2.55% of the administered dose). The proposed
metabolic pathway appeared to be conversion of the parent compound
mainly to 3-hydroxymethyl-sulfentrazone (excreted in urine and feces).
II. Aggregate Exposures
1. Food and feed uses. The primary source for human exposure to
sulfentrazone will be from ingestion of both raw and processed
agricultural commodities from soybeans. A DRES chronic exposure
analysis was performed using tolerance level residues and 100% crop
treated information to estimate the Theoretical Maximum Residue
Contribution (TMRC) for the general population and 22 subgroups. The
chronic analysis showed that exposure from the proposed new tolerance,
in/on soybeans, on cereal grains (excluding sweet corn), on bran of
cereal grains, milk, eggs, and meat for children 1 to 6 years old (the
subgroup with the highest exposure) would be 38.8% of the RfD. The
exposure for the general U.S. population would be 16.7% of the RfD.
The analysis for sulfentrazone is a worst case estimate of dietary
exposure with all residues at tolerance level and 100 percent of the
commodities assumed to be treated with sulfentrazone. Even without
refinements, the chronic dietary risk exposure to sulfentrazone appears
to be minimal for this petition.
2. Potable water. A ground water exposure estimate for
sulfentrazone is based on findings from a voluntary prospective ground
water study conducted in a sandy (worst case) site in North Carolina.
Although this single ground water monitoring study was incomplete,
enough data were collected to confirm that sulfentrazone leaches
substantially to ground water in areas with sandy soils. Sulfentrazone
was found in ground water at concentrations as high as 37 parts per
billion (ppb) in shallow wells and 19 ppb in deeper wells. Residues in
shallow ground water were highly persistent and only slowly dissipated,
with little change in concentrations over a 1-year period, at which
time sampling was terminated. The use of 37 ppb in estimating dietary
exposure through ground water represents the worst case. The worst case
is based on soil type (sandy) and a limited population that would
obtain their drinking water from wells in this type of soil. However,
HED feels that due to sulfentrazone's mobility (Koc = 43; Kd = 0.2-0.8)
and persistence (9 year half life), over time the worst case
values may be approached in more typical ground water settings. Using
37 ppb, the dietary exposure from potable water is 0.00105 mg/kg/day to
adults and 0.0037 mg/kg/day for children 1 to 6 years old.
3. Non-dietary uses. Since the petition for use of sulfentrazone is
limited to commercial soybean production, no non-dietary exposures are
expected for the general population.
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.'' While 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 capability to
resolve the scientific issues concerning common mechanism of toxicity
in a meaningful way. EPA is commencing 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 enable the Agency to apply common mechanism issues to its
pesticide risk assessments. At present, however, the Agency does not
know how to apply the information in its files concerning common
mechanism issues to risk assessments, and therefore believes that in
most cases there is no ``available information'' concerning common
mechanism that can be scientifically applied to tolerance decisions.
Where it is clear that a particular pesticide may share a significant
common mechanism with other chemicals, or where it is clear that a
pesticide does not share a common mechanism with other chemicals, a
tolerance decision may be affected by common mechanism issues. The
Agency expects that most tolerance decisions will fall into the area in
between, where EPA cannot reasonably determine whether a pesticide does
or does not share a common mechanism of toxicity with other chemicals
(and, if so, how that common mechanism should be factored into a risk
assessment). In such circumstances, the Agency will reach a tolerance
decision based on the best, currently-available and usable information,
without regard to common mechanism issues. However, the Agency will
also revisit such decisions when the Agency determines how to apply
common mechanism information to pesticide risk assessments.
In the case of sulfentrazone, EPA has determined that it does not
now have the capability to apply the information in its files to a
resolution of common mechanism issues in a manner that would be useful
in a risk assessment. This tolerance determination therefore does not
take into account common mechanism issues. The Agency will reexamine
the tolerances for sulfentrazone, if reexamination is appropriate,
after the Agency has determined how to apply common mechanism issues to
its pesticide risk assessments.
III. Determination of Safety for U.S. Population and Children
1. The U.S. population. Based on a NOEL of 14 mg/kg/day body weight
(bwt)/day from a two-generation rat reproduction study that
demonstrated histopathological findings in testes and epididymides of
second generation males as an endpoint, and using an uncertainty factor
of 1,000, the Agency has determined a reference dose (RfD) of 0.014 mg/
kg bwt/day for this assessment of risk. The extra factor of 10 and the
uncertainty factor of 1,000 is to provide
[[Page 10706]]
added protection for infants and children. Based on the available
toxicity data and the available exposure data identified above, the
proposed tolerances will utilize 16.7% of the RfD for the U.S.
population. Including an estimated exposure of 37 ppb in potable water,
and assuming the injection of two liters of water per day, the dietary
exposure for the U.S. adult population is increased and utilizes
approximately 25% of the RfD.
2. Children (1 to 6 years old). Using the RfD of 0.014 mg/kg bwt/
day, as described above, and a Theoretical Maximum Residue Contribution
(TMRC) of 0.005437 mg/kg bwt/day determined for children (1 to 6 years
old), the proposed tolerances will utilize 38.8% of the RfD. Including
an estimated exposure of 37 ppb in potable water, and assuming the
injection of 1 liter of water per day, the dietary exposure for
children (1 to 6 years old) population is increased and utilizes
approximately 65% of the RfD.
3. Non-food uses. There are no non-food uses of sulfentrazone
registered under the Federal Insecticide, Fungicide and Rodenticide
Act, as amended.
IV. Determination of Safety for Infants and Children
Risk to infants and children was determined by use of developmental
toxicity studies in rats and a two-generation reproduction study in
rats. The oral developmental toxicity studies resulted in a maternal
NOEL of 25 mg/kg/day based on decreased body weight gain, increased
spleen weight, and microscopic changes in the spleen, and a fetal NOEL
of 10 mg/kg/day based on fetal death, reduced body weights, and
alterations in skeletal development at higher doses. A dermal
developmental toxicity study in rats resulted in a developmental
(fetal) NOEL of 100 mg/kg/day based on decreased fetal body weight and
increased incidences of fetal alterations, comprised primarily of
skeletal variations and reductions in mean numbers of ossification
sites. A two-generation reproduction study in rats resulted in a NOEL
for systemic and reproductive/developmental parameters of 14 mg/kg/day
for males and 16 mg/kg/day for females. The LOEL for systemic and
reproductive/development parameters was 33 mg/kg/day for males and 40
mg/kg/day for females. Systemic effects were comprised of decreased
body weight gains, and reproductive/developmental effects at the LOEL
included degeneration and/or atrophy of the testes, with epididymal
sperm deficits in the second (F1) generation males. Male fertility in
the F1 generation was reduced at higher doses; litter size, pup
survival and pup body weight for both generations were also effected at
higher doses.
FFDCA section 408 provides that EPA shall apply an additional
safety factor for infants and children in the case of threshold effects
to account for pre- and post-natal toxicity and the completeness of the
data base, unless EPA determines that such an additional factor is not
necessary to protect the safety of infants and children. Based on
current data requirements, the data base relative to pre- and post-
natal toxicity is complete. EPA has determined that the toxicology data
profile for sulfentrazone contains clear, unequivocal evidence that
this chemical causes developmental and reproductive toxicity. Based
upon the available data and toxicity profile, the Agency RfD Peer
Review Committee considered sulfentrazone to be a relatively potent
reproductive/developmental toxicant, and determined that an additional
10-fold uncertainty factor for the protection of infants and children
was warranted.
This decision was based upon the data described above. The
following facts were considered in reaching this conclusion:
(1) The lowest NOEL for chronic exposure, which is used to
determine the RfD, is based upon severe, irreversible reproductive/
developmental effects, observed in the two-generation reproduction
study in rats.
(2) Developmental toxicity was observed in the absence of maternal
effects in the prenatal developmental toxicity studies in rats
(developmental NOELs were lower than maternal NOELs). This apparent
increased sensitivity of the fetuses occurred following administration
of sulfentrazone by either the dermal or the oral route, both of which
are relevant to human exposure.
(3) A steep dose-response curve exists for the reproductive and
developmental endpoints of concern. The reproductive and/or
developmental LOELs for the prenatal developmental toxicity studies in
rats and the two-generation reproduction study are only approximately
2.5 times greater than the corresponding NOELs in each of these
studies. The reproductive and developmental NOELs are extremely low
(i.e., in the range of 10 to 13 mg/kg/day). Additionally, in the rat
prenatal developmental toxicity and two-generation reproduction
studies, the reproductive/developmental effects increase in incidence
and/or severity at higher doses.
(4) The reproductive/developmental toxicity profile is consistent
and reproducible, providing a large measure of confidence in the
endpoints and dose levels.
The percent of the RfD that will be utilized by the aggregate
exposure to sulfentrazone for the most exposed subgroup would be 65%
for children (1 to 6 years old) Therefore, EPA concludes that there is
a reasonable certainty that no harm will result to infants and children
from aggregate exposure.
V. 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 or reproductive
toxicology studies described above. There was no observed pathology of
the endocrine organs in these studies. There is no evidence at this
time that sulfentrazone causes endocrine effects.
2. Metabolism in plants and animals. The metabolism of
sulfentrazone in plants and animals is adequately understood for the
purposes of these tolerances. Crop residues found after the pre-
emergence use were the major metabolites 3-hydroxymethyl sulfentrazone
and 3-desmethyl sulfentrazone. In rotational crops, sulfentrazone is
metabolized via four different pathways: (i) Oxidation of the 3-methyl
group to form 3-hydroxymethyl sulfentrazone, followed by further
oxidation to form sulfentrazone carboxylic acid which is decarboxylated
to 3-desmethyl sulfentrazone; (ii) hydrolysis of the trifluoromethyl
group to form desdifluoromethyl sulfentrazone which is oxidized and
decarboxylated to form desdifluoromethyl desmethyl sulfentrazone; (iii)
hydrolysis of the sulfonamide group to form desmethylsulfonyl
sulfentrazone; and (iv) scission of the phenyl and triazole rings to
produce methyl triazole. The corresponding phenyl metabolites are
believed to remain bound. In animal metabolism sulfentrazone per se was
the predominant component of the residue. The metabolite 3-
hydroxymethyl sulfentrazone was also identified. It was determined by
EPA that a soybean tolerance based on the parent and 3-hydroxymethyl
sulfentrazone is therefore appropriate.
3. Analytical method. There is a practical analytical method for
detecting and measuring levels of sulfentrazone 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 these tolerances. The
proposed analytical method for determining residues is hydrolysis
[[Page 10707]]
followed by gas chromatographic separation. EPA will provide
information on this method to the Food and Drug Administration. Because
of the long lead time from establishing these tolerances to publication
the enforcement methodology is being made available in the interim to
anyone interested in pesticide enforcement when requested by mail from:
Calvin Furlow, Public Response Branch, Field Operations Division
(7506C), Office of Pesticide Programs, Environmental Protection Agency,
401 M St., SW., Washington, DC 20460. Office location and telephone
number: Rm. 1130A, CM #2, 1921 Jefferson Davis Highway, Arlington, VA
22202, (703) 305-5937.
4. International tolerances. There are no Codex Alimentarius
Commission (Codex) Maximum Residue Levels (MRLs) for sulfentrazone.
5. Data Gaps. Data gaps currently exist for a 21-day dermal study
in rabbits, in vivo cytogenetics dominant lethal assay in rats, a wheat
processing study, additional rice field trials and residue data for
sorghum aspirated grain fractions. Based on the toxicological data and
the levels of exposure, EPA has determined that the proposed tolerances
will be safe.
VI. Summary of Findings
The analysis for sulfentrazone using tolerance level residues shows
the proposed uses on soybeans will not cause exposure to exceed the
levels at which the Agency believes there is an appreciable risk. All
population subgroups examined by EPA are exposed to sulfentrazone
residues at levels below 100% of the RfD for chronic effects.
Based on the information cited above, the Agency has determined
that the establishment of the tolerances by adding a new section to 40
CFR part 180 will be safe; therefore, the tolerances are established as
set forth below.
VII. 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 appropriate adjustments to
reflect the new law.
Any person may, by May 9, 1997, file written objections to any
aspect of this regulation (including the automatic revocation
provision) 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.
VIII. Public Docket
A record has been established for this rulemaking under docket
control number PF-670/OPP-300459. 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 Rm. 1132 of the Public
Response and Program Resources Branch, Field Operation Division
(7506C), Office of Pesticide Programs, Environmental Protection Agency,
Crystal Mall #2, 1921 Jefferson Davis Highway, Arlington, VA. EPA has
also established a special record for post-FQPA tolerances which
contains documents of general applicability. This record can be found
in the same location.
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.
IX. 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.
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).
[[Page 10708]]
List of Subjects in 40 CFR Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.
Dated: February 27, 1997.
Daniel M. Barolo,
Director, Office of Pesticide Programs.
Therefore, 40 CFR part 180 is amended as follows:
PART 180--[AMENDED]
1. The authority citation for part 180 continues to read as
follows:
Authority: 21 U.S.C. 346a and 371.
2. By adding Sec. 180.498 to read as follows:
Sec. 180.498 Sulfentrazone; tolerances for residues.
(a) Tolerance--general. A tolerance is established for combined
residues of the herbicide sulfentrazone N-[2,4-dichloro-5-[4-
(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-
yl]phenyl]methanesulfonamide and its major metabolite 3-hydroxymethyl
sulfentrazone N-[2,4-dichloro-5-[4-(difluoromethyl)-4,5-dihydro-3-
hydroxymethyl-5-oxo-1H-1,2,4-triazol-1-yl]phenyl]methanesulfonamide in
or on the following raw agricultural commodity:
------------------------------------------------------------------------
Parts per
Commodity million
------------------------------------------------------------------------
Soybean, seed.............................................. 0.05
------------------------------------------------------------------------
(b) Tolerances--inadvertent and indirect residues. Tolerances are
established for inadvertent and indirect combined residues of the
herbicide sulfentrazone (N-[2,4-dichloro-5-[4-(difluoromethyl)-4,5-
dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]phenyl]methanesulfonamide)
and its metabolites 3-hydroxymethyl sulfentrazone (N-[2,4-dichloro-5-
[4-(difluoromethyl)-4,5-dihydro-3-hydroxymethyl-5-oxo-1H-1,2,4-triazol-
1-yl]phenyl]methanesulfonamide) and 3-desmethyl sulfentrazone (N-[2,4-
dichloro-5-[4-(difluoromethyl)-4,5-dihydro-5-oxo-1H-1,2,4-triazol-l-
yl]phenyl]methanesulfonamide) in or on the following raw agricultural
commodities when present therein as a result of the application of
sulfentrazone to growing crops.
------------------------------------------------------------------------
Parts per
Commodity million
------------------------------------------------------------------------
Cereal Grains (excluding sweet corn), Bran................. 0.15
Cereal Grains (excluding sweet corn), Forage............... 0.2
Cereal Grains (excluding sweet corn), Grain................ 0.1
Cereal Grains (excluding sweet corn), Hay.................. 0.2
Cereal Grains (excluding sweet corn), Hulls................ 0.30
Cereal Grains (excluding sweet corn), Stover............... 0.1
Cereal Grains (excluding sweet corn), Straw................ 0.6
------------------------------------------------------------------------
[FR Doc. 97-5874 Filed 3-7-97; 8:45 am]
BILLING CODE 6560-50-F
