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sethoxydim (Poast) Pesticide Tolerances for Emergency Exemptions 10/99

  

[Federal Register: October 21, 1999 (Volume 64, Number 203)]
[Rules and Regulations]               
[Page 56697-56703]
>From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21oc99-10]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-300932; FRL-6385-9]
RIN 2070-AB78

 
Sethoxydim; Pesticide Tolerances for Emergency Exemptions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes a time-limited tolerance for 
combined residues of sethoxydim and its metabolites containing the 2-
cyclohexen-1-one moiety (calculated as the herbicide) in or on 
buckwheat. This action is in connection with a crisis exemption 
declared under section 18 of the Federal Insecticide, Fungicide, and 
Rodenticide Act authorizing use of the pesticide on buckwheat. This 
regulation establishes a maximum permissible level for residues of 
sethoxydim in this food commodity. The tolerance will expire and is 
revoked on December 31, 2001.

DATES: This regulation is effective October 21, 1999. Objections and 
requests for hearings, identified by docket control number OPP-300932, 
must be received by EPA on or before December 20, 1999.

ADDRESSES: Written objections and hearing requests may be submitted by 
mail, in person, or by courier. Please follow the detailed instructions 
for each method as provided in Unit VII. of the ``SUPPLEMENTARY 
INFORMATION.'' To ensure proper receipt by EPA, your objections and 
hearing requests must identify docket control number OPP-300932 in the 
subject line on the first page of your response.

FOR FURTHER INFORMATION CONTACT: By mail: Libby Pemberton, Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 401 M St., SW., Washington, DC 20460; telephone 
number: (703) 308-9364; and e-mail address: pemberton.libby@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you are an 
agricultural producer, food manufacturer, or pesticide manufacturer. 
Potentially

[[Page 56698]]

affected categories and entities may include, but are not limited to:

------------------------------------------------------------------------
 Categories    NAICS        Examples of Potentially Affected Entities
------------------------------------------------------------------------
   Industry        111  Crop production
                   112  Animal production
                   311  Food manufacturing
                 32532  Pesticide manufacturing
------------------------------------------------------------------------

    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in the table could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether or not this action might apply to certain entities. If you have 
questions regarding the applicability of this action to a particular 
entity, consult the person listed under ``FOR FURTHER INFORMATION 
CONTACT.''

B. How Can I Get Additional Information, Including Copies of This 
Document and Other Related Documents?

    1. Electronically.You may obtain electronic copies of this 
document, and certain other related documents that might be available 
electronically, from the EPA Internet Home Page at http://www.epa.gov/. 
To access this document, on the Home Page select ``Laws and 
Regulations'' and then look up the entry for this document under the 
``Federal Register--Environmental Documents.'' You can also go directly 
to the Federal Register listings at http://www.epa.gov/fedrgstr/.
    2. In person. The Agency has established an official record for 
this action under docket control number OPP-300932. The official record 
consists of the documents specifically referenced in this action, and 
other information related to this action, including any information 
claimed as Confidential Business Information (CBI). This official 
record includes the documents that are physically located in the 
docket, as well as the documents that are referenced in those 
documents. The public version of the official record does not include 
any information claimed as CBI. The public version of the official 
record, which includes printed, paper versions of any electronic 
comments submitted during an applicable comment period is available for 
inspection in the Public Information and Records Integrity Branch 
(PIRIB), Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy., 
Arlington, VA, from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. The PIRIB telephone number is (703) 305-5805.

II. Background and Statutory Findings

    EPA, on its own initiative, in accordance with sections 408 (l)(6) 
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a, is 
establishing a tolerance for combined residues of the herbicide 
sethoxydim (2-[1-(ethoxyimino]butyl)-5-[2-(ethylthio)propyl]-3-hydroxy-
2- cyclohexen-1-one) and its metabolites containing the 2-cyclohexen-1-
one moiety (calculated as the herbicide), in or on buckwheat at 10 part 
per million (ppm). This tolerance will expire and is revoked on 
December 31, 2001. EPA will publish a document in the Federal Register 
to remove the revoked tolerance from the Code of Federal Regulations.
    Section 408(l)(6) of the FFDCA requires EPA to establish a time-
limited tolerance or exemption from the requirement for a tolerance for 
pesticide chemical residues in food that will result from the use of a 
pesticide under an emergency exemption granted by EPA under section 18 
of FIFRA. Such tolerances can be established without providing notice 
or period for public comment. EPA does not intend for its actions on 
section 18 related tolerances to set binding precedents for the 
application of section 408 and the new safety standard to other 
tolerances and exemptions.
    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 and in residential settings, 
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....''
    Section 18 of the Federal Insecticide, Fungicide, and Rodenticide 
Act (FIFRA) authorizes EPA to exempt any Federal or State agency from 
any provision of FIFRA, if EPA determines that ``emergency conditions 
exist which require such exemption.'' This provision was not amended by 
the Food Quality Protection Act (FQPA). EPA has established regulations 
governing such emergency exemptions in 40 CFR part 166.

III. Emergency Exemption for Sethoxydim on Buckwheat and FFDCA 
Tolerances

    On June 18, 1999, the North Dakota Department of Agriculture 
availed itself of the authority to declare the existence of a crisis 
situation within the state, thereby authorizing use under FIFRA section 
18 of sethoxydim on buckwheat for control of volunteer grains, foxtail, 
and quackgrass. Abnormal weather consisting of above average rainfall 
and cooler temperatures combined with a lack of labeled products 
available for grass control in buckwheat has resulted in increased 
germination of volunteer cereal grains, foxtail and quackgrass. The 
densities of these pests would cause economic loss if not controlled.
    As part of its assessment of this emergency exemption, EPA assessed 
the potential risks presented by residues of sethoxydim in or on 
buckwheat. In doing so, EPA considered the safety standard in FFDCA 
section 408(b)(2), and EPA decided that the necessary tolerance under 
FFDCA section 408(l)(6) would be consistent with the safety standard 
and with FIFRA section 18. Consistent with the need to move quickly on 
the emergency exemption in order to address an urgent non-routine 
situation and to ensure that the resulting food is safe and lawful, EPA 
is issuing this tolerance without notice and opportunity for public 
comment as provided in section 408(l)(6). Although this tolerance will 
expire and is revoked on December 31, 2001, under FFDCA section 
408(l)(5), residues of the pesticide not in excess of the amounts 
specified in the tolerance remaining in or on buckwheat after that date 
will not be unlawful, provided the pesticide is applied in a manner 
that was lawful under FIFRA, and the residues do not exceed a level 
that was authorized by this tolerance at the time of that application. 
EPA will take action to revoke this tolerance earlier if any experience 
with, scientific data on, or other relevant information on this 
pesticide indicate that the residues are not safe.
    Because this tolerance is being approved under emergency 
conditions, EPA has not made any decisions about whether sethoxydim 
meets EPA's registration requirements for use on buckwheat or whether a 
permanent

[[Page 56699]]

tolerance for this use would be appropriate. Under these circumstances, 
EPA does not believe that this tolerance serves as a basis for 
registration of sethoxydim by a State for special local needs under 
FIFRA section 24(c). Nor does this tolerance serve as the basis for any 
State other than North Dakota to use this pesticide on this crop under 
section 18 of FIFRA without following all provisions of EPA's 
regulations implementing section 18 as identified in 40 CFR part 166. 
For additional information regarding the emergency exemption for 
sethoxydim, contact the Agency's Registration Division at the address 
provided under ``FOR FURTHER INFORMATION CONTACT.''

IV. Aggregate Risk Assessment and Determination of Safety

    EPA performs a number of analyses to determine the risks from 
aggregate exposure to pesticide residues. For further discussion of the 
regulatory requirements of section 408 and a complete description of 
the risk assessment process, see the final rule on Bifenthrin Pesticide 
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).
    Consistent with section 408(b)(2)(D), EPA has reviewed the 
available scientific data and other relevant information in support of 
this action. EPA has sufficient data to assess the hazards of 
sethoxydim and to make a determination on aggregate exposure, 
consistent with section 408(b)(2), for a time-limited tolerance for 
combined residues of sethoxydim (2-[1- (ethoxyimino]butyl)-5-[2-
(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one) and its metabolites 
containing the 2-cyclohexen-1-one moiety (calculated as the herbicide) 
on buckwheat at 10 ppm. EPA's assessment of the dietary exposures and 
risks associated with establishing the tolerance follows.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its 
validity, completeness, and reliability as well as the relationship of 
the results of the studies to human risk. EPA has also considered 
available information concerning the variability of the sensitivities 
of major identifiable subgroups of consumers, including infants and 
children. The nature of the toxic effects caused by sethoxydim are 
discussed in this unit.

B. Toxicological Endpoint

    1. Acute toxicity. In a rat developmental study rats received doses 
of 0, 50, 180, 650, and 1,000 milligrams/kilogram/day (mg/kg/day). The 
maternal toxicity no-observed-adverse-effect level (NOAEL) was 180 mg/
kg/day and the lowest-observed-adverse-effect level (LOAEL) was 650 mg/
kg/day based on irregular gait, decreased activity, excessive 
salivation, and ano-genital staining. For developmental toxicity the 
NOAEL was 180 mg/kg/day and the LOAEL was 650 mg/kg/day based on 21-22% 
decrease in fetal weights, filamentous tail and lack of tail due to the 
absence of accral and/or caudal vertebrae, and delayed ossification in 
the hyoids, vertebral centrum and/or transverse processes, sternebrae 
and/or metatarsal, and pubes. The end point for use in the risk 
assessment is the maternal NOAEL of 180 mg/kg/day. The end point is set 
on maternal effects because the NOAEL for developmental effects is also 
180 mg/kg/day.
    2. Short- and intermediate-term toxicity. No short- or 
intermediate-dermal or inhalation endpoints were identified. In a 21 
day dermal study with rabbits dosed at 0, 40, 200, or 1,000 mg/kg/day, 
there was no evidence of compound related toxicity on clinical signs, 
body weights, food consumption, food efficiency, eye health, clinical 
pathology, organ weights, or gross pathology. The NOAEL was greater 
than 1,000 mg/kg/day (limit dose) in the acute inhalation study with 
rats the LC<INF>50</INF> was 6.03 mg/l (males) and 6.28 mg/l (females), 
placing sethoxydim in category IV.
    3. Chronic toxicity. EPA has established the Reference Dose (RfD) 
for sethoxydim at 0.9 mg/kg/day. This RfD is based on a finding of 
equivocal anemia in the 1-year dog study. The NOAEL was 8.86 mg/kg in 
males and 9.41 mg/kg in females.
    4. Carcinogenicity. Sethoxydim is not classified. Available studies 
show no evidence of carcinogenicity in rats or mice.

C. Exposures and Risks

    1. From food and feed uses. Tolerances have been established (40 
CFR 180.412) for the combined residues of (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 a variety of raw agricultural commodities. Risk 
assessments were conducted by EPA to assess dietary exposures and risks 
from sethoxydim as follows:
    i. Acute exposure and risk. Acute dietary risk assessments are 
performed for a food-use pesticide if a toxicological study has 
indicated the possibility of an effect of concern occurring as a result 
of a 1-day or single exposure. The acute dietary endpoint is 180 mg/kg/
day based on NOAEL's of 180 mg/kg/day for maternal and developmental 
effects in the rabbit developmental study. The FQPA safety factor of 3x 
was applied to females 13+ only because the endpoint (based on decrease 
in fetal weights, filamentous tail and lack of tail due to absence of 
sacral and/or caudal vertebrae, delayed ossification in the hyoids, 
vertebral centrum and/or transverse processes, sternebrae and/or 
metatarsal) occurs only during in utero exposure and is not a postnatal 
effect. Since the effects occur during in utero exposure, it is not an 
appropriate endpoint for acute dietary risk assessment of infants and 
children.
     In conducting this acute dietary risk assessment, the Agency made 
very conservative assumptions--100% of all commodities having 
sethoxydim tolerances will contain sethoxydim regulable residues and 
those residues will be at the level of the tolerance--which result in 
an over estimation of human dietary exposure.
     From the acute dietary (food only) risk assessment, a high-end 
exposure estimate of 0.2 mg/kg/day was calculated. This exposure 
yielded dietary (food only) margins of exposure (MOEs) ranging from 420 
for children (1-6 years old) to 622 for female 13+ and greater than 500 
for all other subgroups.
    ii. Chronic exposure and risk. The FQPA Safety Factor will not be 
applied for chronic dietary risk assessment because the endpoint is 
based on anemia in male dogs. The endpoint for which the FQPA safety 
factor is based is an in utero effect and can not result from postnatal 
exposure. There was no indication of increased susceptibility in the 
prenatal developmental study in rabbits following in utero exposure. In 
the 2-generation reproduction study in rats, effects in offspring were 
observed only at above treatment levels which resulted in evidence of 
appreciable parental toxicity. No increased susceptibility was 
demonstrated in the developmental toxicity study with rats when the 
maternal and developmental NOAELs/LOAELs were compared.
     In conducting this chronic dietary risk assessment, the Agency has 
made very conservative assumptions no percent crop-treated data were 
used and all commodities having sethoxydim tolerances will contain 
sethoxydim residues and those residues will be at the level of the 
tolerance which will result in an overestimate of human dietary 
exposure.
     The sethoxydim tolerances (published and pending) result in a 
Theoretical Maximum Residue Contribution

[[Page 56700]]

(TMRC) that is equivalent to the following percentages of the RfD:


------------------------------------------------------------------------
                        Subgroup                           TMRC    %RFD
------------------------------------------------------------------------
U.S. Population........................................  0.03966      44

All Infants............................................  0.06666      74

Nursing Infants........................................  0.02027      22

Non-Nursing Infants (< 1 year old).....................  0.08619      96

Children (1-6 years old)...............................  0.08635      95

Children (7-12 years old)..............................  0.05859      65

Female (13+, nursing)..................................  0.04115      46

Males (13-19 years old)................................  0.04074      45

U.S Population (Autumn Season).........................  0.04115      46

Northeast Region.......................................  0.04121      46

Hispanics..............................................  0.04016      45

Non-Hispanic Others....................................  0.04119      46
------------------------------------------------------------------------

    The subgroups listed above are (1) the U.S. population (48 states); 
(2) those for infants, children, females, 13+ nursing; and other 
subgroups for which the percentage of RfD occupied is greater than 
occupied by the subgroup U.S. population.
    2. From drinking water. Based on information available, sethoxydim 
is a non-persistent, but highly mobile compound in soil and water 
environments. There are no Maximum Contaminant Levels or Health 
Advisories established for sethoxydim residues in drinking water.
    For this proposed Section 18 use, EPA used the Screening 
Concentration In GROund Water (SCI-GROW) model to estimate the 
concentration of sethoxydim residues in ground water. The maximum long-
term estimated concentration is not expected to exceed 3 parts per 
billion (ppb) (chronic), and the maximum residue concentration using an 
average anaerobic half-life of 85 days, is predicted to be 33 ppb 
(acute); EPA used the generic expected environmental concentration 
(GENEEC) model to estimate the concentration of sethoxydim residues in 
surface water. The peak expected environmental concentration (EEC) was 
42 ppb (acute), while the 56-day average EEC was 27 ppb (chronic).
    3. From non-dietary exposure. Sethoxydim is currently registered 
for use on the following residential non-food sites: ornamentals and 
flowering plants, recreational areas, and buildings/structures (outdoor 
non-agricultural). These residential uses comprise a short- and 
intermediate-term exposure scenario, but do not comprise a chronic 
exposure scenario.
    i. Acute exposure and risk. There is a potential for exposure to 
sethoxydim by homeowner mixers/applicators. However, since no endpoints 
for dermal or inhalation were selected, the use on residential non-food 
sites is not expected to pose an unacceptable acute risk.
    ii. Chronic exposure and risk. The registered uses for sethoxydim 
do not comprise a chronic exposure scenario. A chronic non-dietary 
endpoint was not selected; therefore, the use on residential non-food 
sites is not expected to pose an unacceptable chronic risk.
    iii. Short- and intermediate-term exposure and risk. Short-term or 
intermediate-term endpoints were not identified. However, the following 
scenarios may result if herbicides containing sethoxydim are applied to 
residential turf, and/or ornamental plants: incidental non-dietary 
ingestion of residues on lawns from hand-to-mouth transfer, ingestion 
of pesticide-treated turfgrass, and incidental ingestion of soil from 
treated lawns. A residential exposure estimate and risk assessment was 
conducted for postapplication exposure following the application of 
sethoxydim on turf and ornamental gardens. The acute dietary endpoint 
was used for this risk assessment because the acute dietary endpoint 
provides the worst case estimate of risk and exposure for these use 
patterns. The assessment was performed using Draft SOPs for Residential 
Exposure Assessments (12/18/98). The proposed postapplication aggregate 
exposure assessment takes into account chronic dietary exposure plus 
outdoor residential exposures. These exposure assessments assume that 
20 percent of the application rate is available from the turf grass as 
dislodgeable residue and 2 hours as the duration of exposure. These 
assumptions are considered conservative and protective.
     Exposures and MOEs were calculated to be 0.053 mg/kg/day (MOE of 
3400) for hand to mouth transfer for treated lawns (toddlers), 0.0012 
mg/kg/day (MOE of 150,000) for ingestion of treated turf grass 
(toddler), and 0.000025 (MOE of 7,000,000) for incidental ingestion of 
soil (toddlers). MOEs exceeded 100 for all three scenarios. MOEs 
greater than or equal to 100 do not exceed the Agency's level of 
concern.
    4. Cumulative exposure to substances with a 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.''
    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 substances. For more information regarding EPA's efforts to 
determine which chemicals have a common mechanism of toxicity and to 
evaluate the cumulative effects of such chemicals, see the final rule 
for Bifenthrin Pesticide Tolerances (62 FR 62961, November 26, 1997).

D. Aggregate Risks and Determination of Safety for U.S. Population

    1. Acute risk. Using the published and pending tolerances, the 
dietary (food only) acute MOEs range from 420 for children (1-6 year) 
to 622 for females 13+ years. The level of concern for females 13 + 
years is 300 (includes 3X safety factor) for acute sethoxydim exposure 
and 100 for all other population subgroups. This risk estimate should 
be viewed as highly conservative; refinement using anticipated residue 
values and percent crop treated data in conjunction with Monte Carlo 
analysis will result in a lower acute dietary exposure estimate. The 
dietary exposure does not exceed the Agency's level of concern.
     Sethoxydim is a non persistent, but highly mobile compound in soil 
and water environments. The modeling data for sethoxydim in drinking 
water indicate levels less than OPP`s DWLOC for acute exposure. Since a 
refined acute risk for food only would not exceed EPA's levels of 
concern for acute dietary exposures and the monitoring and modeling 
levels in water are less than the acute DWLOC, EPA does not expect 
aggregate acute exposure to sethoxydim will pose an unacceptable risk 
to human health.
    2. Chronic risk. Using the TMRC exposure assumptions described in 
this unit, EPA has concluded that aggregate exposure to sethoxydim from 
food will utilize 44 percent of the RfD for the U.S. population. The 
major identifiable subgroup with the highest aggregate exposure is 95% 
for children 1 to 6 years; discussed below. EPA generally

[[Page 56701]]

has no concern for exposures below 100% of the RfD because the RfD 
represents the level at or below which daily aggregate dietary exposure 
over a lifetime will not pose appreciable risks to human health. 
Despite the potential for exposure to sethoxydim in drinking water and 
from non- dietary, non-occupational exposure, EPA does not expect the 
aggregate exposure to exceed 100% of the RfD.
    3. Short- and intermediate-term risk.  Short- and intermediate-term 
aggregate exposure takes into account chronic dietary food and water 
(considered to be a background exposure level) plus indoor and outdoor 
residential exposure.
    Endpoints for short or intermediate term were not selected. An 
aggregate exposure estimate and risk assessment was conducted for post-
application exposure to sethoxydim on turf and ornamental plants taking 
into account chronic exposure from food and the acute dietary NOAEL. 
The resulting MOEs (1390-2350) are not of concern to the Agency.
    4. Aggregate cancer risk for U.S. population. Sethoxydim has not 
ben classified. Available studies do not show evidence of 
carcinogenicity in rats or mice.
    5. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
from aggregate exposure to sethoxydim residues.

E. Aggregate Risks and Determination of Safety for Infants and Children

    1. Safety factor for infants and children-- i. In general. In 
assessing the potential for additional sensitivity of infants and 
children to residues of sethoxydim, EPA considered data from 
developmental toxicity studies in the rat and rabbit and a 2-generation 
reproduction study in the rat. The developmental toxicity studies are 
designed to evaluate adverse effects on the developing organism 
resulting from maternal pesticide exposure during gestation. 
Reproduction studies provide information relating to effects from 
exposure to the pesticide on the reproductive capability of mating 
animals and data on systemic toxicity.
    FFDCA section 408 provides that EPA shall apply an additional 
tenfold margin of safety for infants and children in the case of 
threshold effects to account for prenatal and postnatal toxicity and 
the completeness of the data base unless EPA determines that a 
different margin of safety will be safe for infants and children. 
Margins of safety are incorporated into EPA risk assessments either 
directly through use of a margin of exposure (MOE) analysis or through 
using uncertainty (safety) factors in calculating a dose level that 
poses no appreciable risk to humans. EPA believes that reliable data 
support using the standard MOE and uncertainty factor (usually 100 for 
combined interspecies and intraspecies variability) and not the 
additional tenfold MOE/uncertainty factor 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/safety factor.
    ii. Prenatal and postnatal sensitivity. There was no indication of 
increased susceptibility in the prenatal developmental toxicity study 
in rabbits following in utero exposure. In the 2-generation 
reproduction study in rats, effects in the offspring were observed only 
at or above treatment levels which resulted in evidence of appreciable 
parental toxicity. No increased susceptibility was demonstrated in the 
developmental toxicity studies; however developmental toxic effects, 
were observed at the highest dose tested (LOAEL).
     Acceptable developmental toxicity studies have been performed in 
rats and rabbits; an acceptable 2-generation reproduction study has 
also been performed in rats. A chronic feeding/carcinogenicity 
guideline study in rats has been submitted and is currently undergoing 
review. An initial examination of the study supports the current 
findings of no evidence of carcinogenicity. There is a complete 
toxicity database for sethoxydim and exposure data is complete or is 
estimated based on data that reasonably accounts for potential 
exposures.
    The FQPA Safety Factor is to be retained in case of developmental 
toxicity in the absence of maternal toxicity. Since malformations were 
seen in the rat study at levels that produced minimal maternal 
toxicity. The Agency concluded that an FQPA safety factor is needed. 
However, it was determined that the 10X safety factor need not be 
retained, instead, the safety factor should be reduced to 3X based on 
the following weight of evidence considerations: (1) developmental 
toxicity was seen in only one species, in the presence of maternal 
toxicity, and at a very high dose (650 mg/kg/day) that approached the 
Limit-Dose of 1,000 mg/kg/day; (2) no developmental toxicity was 
observed in the rabbit study at the highest dose tested (400 mg/kg/
day); (3) there was no increased susceptibility seen in the 2-
generation reproduction study in rats at doses up to 150 mg/kg/day 
(highest dose tested); and (4) lack of concern for structure activity 
relationship (i.e. no significant developmental or reproductive 
toxicity was seen with the structural analog, clethodim.)
     Exposure assessments do not indicate a concern for potential risk 
to infants and children based on; (1) the dietary exposure assessments 
use field study data and assume 100% crop treated which results in an 
overestimate of dietary exposure; (2) limited monitoring data is used 
for ground and surface source drinking water exposure assessments, 
resulting in estimates considered to be reasonable upper-bound 
concentrations; (3) there is a potential for post-application hand-to-
mouth exposure to toddlers associated with lawn use, however, the use 
of conservative models and/or assumptions in the residential exposure 
assessment provide adequate protection of infants and children.
     The FQPA safety factor is applicable for acute dietary risk 
assessment for females 13 + because the endpoint occurs only during in 
utero exposure and is not a postnatal effect. Since the effects occur 
during in utero exposure, it is not an appropriate endpoint for acute 
dietary risk assessment of infants and children. The FQPA safety factor 
is not applied for chronic risk assessment because the endpoint is an 
in utero effect and can not result from postnatal exposure. The FQPA 
safety factor is not applicable to the post-application hand-to-mouth 
exposure associated with the lawn use since this exposure scenario 
would only be expected for toddlers and not for females 13+.
    iii. Conclusion. There is a complete toxicity data base for 
sethoxydim and exposure data are complete or are estimated based on 
data that reasonably accounts for potential exposures.
    2. Acute risk. Using the conservative exposure assumptions that 
100% of the commodities having sethoxydim tolerances will contain 
sethoxydim regulable residues and that those residues will be at the 
level of the tolerance, EPA calculated acute dietary (food only) MOEs 
ranging from 420 for children (1-6 years old) to 622 for females 13+ 
years. The level of concern is 300 (3x safety factor x 100) for females 
13+ years and 100 for all other subgroups.
    3. Chronic risk. Using the exposure assumptions described in this 
unit, EPA has concluded that aggregate exposure to sethoxydim from food 
will utilize less than 100% of the RfD for nursing infants, non-nursing 
infants (< 1 years old), children (1-6 years old), and

[[Page 56702]]

children (7-12 years old). EPA generally has no concern for exposures 
below 100% of the RfD because the RfD represents the level at or below 
which daily aggregate dietary exposure over a lifetime will not pose 
appreciable risks to human health. Despite the potential for exposure 
to sethoxydim in drinking water and from non-dietary, non-occupational 
exposure, EPA does not expect the aggregate exposure to exceed 100% of 
the RfD.
    4. Short- or intermediate-term risk. An aggregate exposure estimate 
and risk assessment was conducted for post-application exposure to 
sethoxydim on turf and ornamental plants taking into account chronic 
exposure from food and the acute dietary NOAEL. The resulting MOEs 
(1,390-2,350) are not of concern to EPA.
    5. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to infants and children from aggregate exposure to sethoxydim residues.

V. Other Considerations

A. Metabolism in Plants and Animals

     The metabolism of sethoxydim in plants and animals is understood. 
The tolerances for plant and animal commodities are expressed as the 
combined residues of sethoxydim and its metabolites containing the 2-
cyclohexen-1-one moiety (calculated as the herbicide).

B. Analytical Enforcement Methodology

    Adequate enforcement methodology (gas-liquid chromatography GLC 
with flame photometric detection) is available (Method I, PAM II) to 
enforce the tolerance expression.

C. Magnitude of Residues

    Residues of sethoxydim and its metabolites containing the 2-
cyclohexen-1-one moiety are not expected to exceed 10.0 ppm in/on 
buckwheat or its processed commodity flour as a result of this Section 
18 use. Secondary residues are not expected in animal commodities as no 
feed items are associated with this Section 18 use.

D. International Residue Limits

    There are no Codex, Canadian, or Mexican residue limits for 
sethoxydim on buckwheat. Therefore, harmonization is not an issue for 
this Section 18 use.

E. Rotational Crop Restrictions

     No rotational crop restrictions are specified in the Section 18 or 
Federal label.

VI. Conclusion

    Therefore, the tolerance is established for combined residues of 
(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 buckwheat at 10 ppm.

VII. Objections and Hearing Requests

    Under section 408(g) of the FFDCA, as amended by the FQPA, any 
person may file an objection to any aspect of this regulation and may 
also request a hearing on those objections. The EPA procedural 
regulations which govern the submission of objections and requests for 
hearings appear in 40 CFR part 178. Although the procedures in those 
regulations require some modification to reflect the amendments made to 
the FFDCA by the FQPA of 1996, EPA will continue to use those 
procedures, with appropriate adjustments, until the necessary 
modifications can be made. The new section 408(g) provides essentially 
the same process for persons to ``object'' to a regulation for an 
exemption from the requirement of a tolerance issued by EPA under new 
section 408(d), as was provided in the old FFDCA sections 408 and 409. 
However, the period for filing objections is now 60 days, rather than 
30 days.

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

    You must file your objection or request a hearing on this 
regulation in accordance with the instructions provided in this unit 
and in 40 CFR part 178. To ensure proper receipt by EPA, you must 
identify docket control number OPP-300932 in the subject line on the 
first page of your submission. All requests must be in writing, and 
must be mailed or delivered to the Hearing Clerk on or before December 
20, 1999.
    1. Filing the request. Your objection must specify the specific 
provisions in the regulation that you object to, and the grounds for 
the objections (40 CFR 178.25). If a hearing is requested, the 
objections must include a statement of the factual issues(s) on which a 
hearing is requested, the requestor's contentions on such issues, and a 
summary of any evidence relied upon by the objector (40 CFR 178.27). 
Information submitted in connection with an objection or hearing 
request may be claimed confidential by marking any part or all of that 
information as CBI. Information so marked will not be disclosed except 
in accordance with procedures set forth in 40 CFR part 2. A copy of the 
information that does not contain CBI must be submitted for inclusion 
in the public record. Information not marked confidential may be 
disclosed publicly by EPA without prior notice.
    Mail your written request to: Office of the Hearing Clerk (1900), 
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460. 
You may also deliver your request to the Office of the Hearing Clerk in 
Rm. M3708, Waterside Mall, 401 M St., SW., Washington, DC 20460. The 
Office of the Hearing Clerk is open from 8 a.m. to 4 p.m., Monday 
through Friday, excluding legal holidays. The telephone number for the 
Office of the Hearing Clerk is (202) 260-4865.
    2. Tolerance fee payment. If you file an objection or request a 
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or 
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must 
mail the fee to: EPA Headquarters Accounting Operations Branch, Office 
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please 
identify the fee submission by labeling it ``Tolerance Petition Fees.''
    EPA is authorized to waive any fee requirement ``when in the 
judgement of the Administrator such a waiver or refund is equitable and 
not contrary to the purpose of this subsection.'' For additional 
information regarding the waiver of these fees, you may contact James 
Tompkins by phone at (703) 305-5697, by e-mail at tompkins.jim@epa.gov, 
or by mailing a request for information to Mr. Tompkins at Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 401 M St., SW., Washington, DC 20460.
    If you would like to request a waiver of the tolerance objection 
fees, you must mail your request for such a waiver to: James Hollins, 
Information Resources and Services Division (7502C), Office of 
Pesticide Programs, Environmental Protection Agency, 401 M St., SW., 
Washington, DC 20460.
    3.  Copies for the Docket. In addition to filing an objection or 
hearing request with the Hearing Clerk as described in Unit VII.A., you 
should also send a copy of your request to the PIRIB for its inclusion 
in the official record that is described in Unit I.B.2. Mail your 
copies, identified by the docket control number OPP-300932, to: Public 
Information and Records Integrity Branch, Information Resources and 
Services Division (7502C), Office of Pesticide Programs, Environmental 
Protection Agency, 401 M St., SW., Washington, DC 20460. In person or 
by courier, bring a copy to the location of the PIRIB described in Unit 
I.B.2. You may also send an electronic copy of your request via e-mail 
to: opp-

[[Page 56703]]

docket@epa.gov. Please use an ASCII file format and avoid the use of 
special characters and any form of encryption. Copies of electronic 
objections and hearing requests will also be accepted on disks in 
WordPerfect 6.1/8.0 file format or ASCII file format. Do not include 
any CBI in your electronic copy. You may also submit an electronic copy 
of your request at many Federal Depository Libraries.

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

    A request for a hearing will be granted if the Administrator 
determines that the material submitted shows the following: There is a 
genuine and substantial issue of fact; there is a reasonable 
possibility that available evidence identified by the requestor would, 
if established resolve one or more of such issues in favor of the 
requestor, taking into account uncontested claims or facts to the 
contrary; and resolution of the factual issues(s) in the manner sought 
by the requestor would be adequate to justify the action requested (40 
CFR 178.32).

VIII. Regulatory Assessment Requirements

    This final rule establishes a tolerance under section 408 of the 
FFDCA. The Office of Management and Budget (OMB) has exempted these 
types of actions from review under Executive Order 12866, entitled 
Regulatory Planning and Review (58 FR 51735, October 4, 1993). This 
final rule does not contain any information collections subject to OMB 
approval under the Paperwork Reduction Act (PRA), 44 U.S.C. 3501 et 
seq., or impose any enforceable duty or contain any unfunded mandate as 
described under Title II of the Unfunded Mandates Reform Act of 1995 
(UMRA) (Public Law 104-4). Nor does it require prior consultation with 
State, local, and tribal government officials as specified by Executive 
Order 12875, entitled Enhancing the Intergovernmental Partnership (58 
FR 58093, October 28, 1993) and Executive Order 13084, entitled  
Consultation and Coordination with Indian Tribal Governments (63 FR 
27655, May 19, 1998), or special consideration of environmental justice 
related issues under Executive Order 12898, entitled  Federal Actions 
to Address Environmental Justice in Minority Populations and Low-Income 
Populations (59 FR 7629, February 16, 1994) or require OMB review in 
accordance with Executive Order 13045, entitled Protection of Children 
from Environmental Health Risks and Safety Risks (62 FR 19885, April 
23, 1997). The Agency has determined that this action will not have a 
substantial direct effect on States, on the relationship between the 
national government and the States, or on the distribution of power and 
responsibilities among the various levels of government, as specified 
in Executive Order 12612, entitled Federalism (52 FR 41685, October 30, 
1987). This action directly regulates growers, food processors, food 
handlers and food retailers, not States. This action does not alter the 
relationships or distribution of power and responsibilities established 
by Congress in the preemption provisions of the Federal Food, Drug, and 
Cosmetic Act, 21 U.S.C. 346a(n)(4). This action does not involve any 
technical standards that would require Agency consideration of 
voluntary consensus standards pursuant to section 12(d) of the National 
Technology Transfer and Advancement Act of 1995 (NTTAA), Public Law 
104-113, section 12(d) (15 U.S.C. 272 note). In addition, since 
tolerances and exemptions that are established under FFDCA section 
408(l)(6), such as the tolerance in this final rule, do not require the 
issuance of a proposed rule, the requirements of the Regulatory 
Flexibility Act (RFA) (5 U.S.C. 601 et seq.) do not apply.

IX. Submission to Congress and the Comptroller General

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. EPA will submit a report containing this rule and other 
required information to the U.S. Senate, the U.S. House of 
Representatives, and the Comptroller General of the United States prior 
to publication of this rule in the Federal Register. This rule is not a 
``major rule'' as defined by 5 U.S.C. 804(2).

List of Subjects in 40 CFR Part 180

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

    Dated: October 5, 1999.

James Jones,

Director, Registration Division, Office of Pesticide Programs.
    Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

    1. The authority citation for part 180 continues to read as 
follows:


     Authority: 21 U.S.C. 321(q), 346(a) and 371.

    2. In Sec. 180.412, the table in paragraph (b) is amended by adding 
an entry for ``buckwheat'' to read as follows:


Sec.  180.412   Sethoxydim; tolerances for residues.

*    *    *    *    *
    (b) *  *  *


------------------------------------------------------------------------
                                      Parts per    Expiration/revocation
             Commodity                 million             date
------------------------------------------------------------------------
Buckwheat..........................           10  12/31/01
          *            *            *            *            *
------------------------------------------------------------------------

*    *    *    *    *

[FR Doc. 99-27391 Filed 10-20-99; 8:45 am]
BILLING CODE 6560-50-F