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Tralkoxydim - Time-Limited Pesticide Tolerances 12/98

[Federal Register: December 16, 1998 (Volume 63, Number 241)]
[Rules and Regulations]
[Page 69194-69200]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16de98-11]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300764; FRL-6048-4]
RIN 2070-AB78
Tralkoxydim; Time-Limited Pesticide Tolerances
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.

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SUMMARY: This regulation establishes time-limited tolerances for
residues of the herbicide tralkoxydim in or on certain raw agricultural
commodities. Zeneca Ag Products requested this tolerance under the
Federal Food, Drug and Cosmetic Act (FFDCA), as amended by the Food
Quality Protection Act of 1996 (Pub. L. 104-170). These tolerances will
expire on February 28, 2003.

DATES: This regulation is effective December 16, 1998. Objections and
requests for hearings must be received by EPA on or before February 16,
1999.

ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [OPP-300764], must 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 identified by the docket
control number, [OPP-300764], must also be submitted 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,
bring a copy of objections and hearing requests to Rm. 119, Crystal
Mall 2 (CM #2), 1921 Jefferson Davis Hwy., Arlington, VA.
    A copy of objections and hearing requests filed with the Hearing
Clerk may also be submitted electronically 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 5.1/6.1
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-300764]. 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: James A. Tompkins,
Registration Division 7505C, Office of Pesticide Programs,
Environmental Protection Agency, 401 M St., S.W., Washington, DC 20460.
Office location, telephone number, and e-mail address: Rm. 239, CM #2,
1921 Jefferson Davis Hwy., Arlington, VA, (703) 305-5697, e-mail:
tompkins.jim@epamail.epa.gov.

SUPPLEMENTARY INFORMATION: In the Federal Register of July 2, 1997 (62
FR 35804)(FRL-5722-9), 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 a pesticide petition (PP 6F4631) for tolerance
by Zeneca Ag Products, 1800 Concord Pike, P.O. Box 15458, Wilmington,
DE 19850-5458. This notice included a summary of the petition prepared
by Zeneca Ag Products, the registrant. There were no comments received
in response to the notice of filing.
    The petition requested that 40 CFR part 180 be amended by
establishing time-limited tolerances for residues of the herbicide,
tralkoxydim, 2-(Cyclohexen-1-one, 2-[1-(ethoxyimino)propyl]-3-hydroxy-
5-(2,4,6-trimethylphenyl)-(9Cl), in or on the raw agricultural
commodities barley grain, barley straw, barley hay, wheat grain, wheat
forage, wheat straw, and wheat hay at 0.1 parts per million (ppm).
Zeneca Ag Products subsequently amended the proposed tolerances to
lower the residue levels, as follows; barley grain, barley hay, wheat
grain and wheat hay at 0.02 ppm, and barley straw, wheat forage and
wheat straw at 0.05 ppm. These tolerances will expire on February 28,
2003.

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 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...."
    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).

A. Toxicity

    1. Threshold and non-threshold effects. For many animal studies, a
dose response relationship can be determined, which provides a dose
that causes adverse effects (threshold effects) and doses causing no
observed effects (the "no-observed adverse effect level" or

"NOAEL").
    Once a study has been evaluated and the observed effects have been
determined to be threshold effects, EPA generally divides the NOAEL
from the study with the lowest NOAEL by an uncertainty factor (usually
100 or more) to determine the Reference Dose (RfD). The RfD is a level
at or below which daily aggregate exposure over a lifetime will not
pose appreciable risks to human health. An uncertainty factor
(sometimes called a "safety factor") of 100 is commonly used since it
is assumed that people may be up to 10 times more sensitive to
pesticides than the test animals, and that one person or subgroup of
the population (such as infants and children) could be up to 10 times
more sensitive to a pesticide than another. In addition, EPA assesses
the potential risks to infants and children based on the weight of the
evidence of the toxicology studies and determines whether an additional
uncertainty factor is warranted. Thus, an aggregate daily exposure to a
pesticide residue at or below the Rfd (expressed as 100% or less of the
RfD) is generally considered acceptable by EPA. EPA generally uses

[[Page 69195]]

the RfD to evaluate the chronic risks posed by pesticide exposure. For
shorter term risks, EPA calculates a margin of exposure (MOE) by
dividing the estimated human exposure into the NOAEL from the
appropriate animal study. Commonly, EPA finds MOEs lower than 100 to be
unacceptable. This 100-fold MOE is based on the same rationale as the
100-fold uncertainty factor.
    Lifetime feeding studies in two species of laboratory animals are
conducted to screen pesticides for cancer effects. When evidence of
increased cancer is noted in these studies, the Agency conducts a
weight of the evidence review of all relevant toxicological data
including short-term and mutagenicity studies and structure activity
relationship. Once a pesticide has been classified as a potential human
carcinogen, different types of risk assessments (e.g., linear low dose
extrapolations or MOE calculation based on the appropriate NOAEL) will
be carried out based on the nature of the carcinogenic response and the
Agency's knowledge of its mode of action.
    2. Differences in toxic effect due to exposure duration. The
toxicological effects of a pesticide can vary with different exposure
durations. EPA considers the entire toxicity data base, and based on
the effects seen for different durations and routes of exposure,
determines which risk assessments should be done to assure that the
public is adequately protected from any pesticide exposure scenario.
Both short and long durations of exposure are always considered.
Typically, risk assessments include "acute", "short-term",
"intermediate term", and "chronic" risks. These assessments are
defined by the Agency as follows.
    Acute risk, by the Agency's definition, results from 1-day
consumption of food and water, and reflects toxicity which could be
expressed following a single oral exposure to the pesticide residues.
High end exposure to food and water residues are typically assumed.
    Short-term risk results from exposure to the pesticide for a period
of 1-7 days, and therefore overlaps with the acute risk assessment.
Historically, this risk assessment was intended to address primarily
dermal and inhalation exposure which could result, for example, from
residential pesticide applications. However, since enaction of FQPA,
this assessment has been expanded to include both dietary and non-
dietary sources of exposure, and will typically consider exposure from
food, water, and residential uses when reliable data are available. In
this assessment, risks from average food and water exposure, and high-
end residential exposure, are aggregated. High-end exposures from all
three sources are not typically added because of the very low
probability of this occurring in most cases, and because the other
conservative assumptions built into the assessment assure adequate
protection of public health. However, for cases in which high-end
exposure can reasonably be expected from multiple sources (e.g.
frequent and widespread homeowner use in a specific geographical area),
multiple high-end risks will be aggregated and presented as part of the
comprehensive risk assessment/characterization. Since the toxicological
endpoint considered in this assessment reflects exposure over a period
of at least 7 days, an additional degree of conservatism is built into
the assessment; i.e., the risk assessment nominally covers 1-7 days
exposure, and the toxicological endpoint/NOAEL is selected to be
adequate for at least 7 days of exposure. (Toxicity results at lower
levels when the dosing duration is increased.)
    Intermediate-term risk results from exposure for 7 days to several
months. This assessment is handled in a manner similar to the short-
term risk assessment.
    Chronic risk assessment describes risk which could result from
several months to a lifetime of exposure. For this assessment, risks
are aggregated considering average exposure from all sources for
representative population subgroups including infants and children.

B. Aggregate Exposure

    In examining aggregate exposure, FFDCA section 408 requires that
EPA take into account available and reliable information concerning
exposure from the pesticide residue in the food in question, residues
in other foods for which there are tolerances, residues in groundwater
or surface water that is consumed as drinking water, and other non-
occupational exposures through pesticide use in gardens, lawns, or
buildings (residential and other indoor uses). 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. In evaluating food
exposures, EPA takes into account varying consumption patterns of major
identifiable subgroups of consumers, including infants and children.
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% of the crop is treated by pesticides that have
established tolerances. If the TMRC exceeds the 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.
    Percent of crop treated estimates are derived from federal and
private market survey data. Typically, a range of estimates are
supplied and the upper end of this range is assumed for the exposure
assessment. By using this upper end estimate of percent of crop
treated, the Agency is reasonably certain that exposure is not
understated for any significant subpopulation group. Further, regional
consumption information is taken into account through EPA's computer-
based model for evaluating the exposure of significant subpopulations
including several regional groups, to pesticide residues. For this
pesticide, the most highly exposed population subgroup children 1-6
years was not regionally based.

II. Aggregate Risk Assessment and Determination of Safety

    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
tralkoxydim and to make a determination on aggregate exposure,
consistent with section 408(b)(2), for a time-limited tolerance for
residues of tralkoxydim in certain raw agricultural commodities. 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

[[Page 69196]]

toxic effects caused by tralkoxydim are discussed below.
    1. A rat acute oral study with a LD50 of 1,258
milligrams (mg)/kilogram (kg) for males and 934 mg/kg for females.
    2. A mouse acute oral study with a LD50 of 1,231 mg/kg
for males and 1,100 mg/kg for females.
    3. A 90-day rat feeding study with a NOAEL of 250 ppm [20.5 mg/kg/
day] and a Lowest Observed Adverse Effect Level (LOAEL) of 2,500 ppm
[204.8 mg/kg/day] based on decreased food efficacy and minor
hematologic changes.
    4. A 90-day dog dietary study with a NOAEL of 0.5 mg/kg/day and a
LOAEL of 5 mg/kg/day based on increased liver weights in males and
increases in APDM in males and females, indicating minimal
hepatotoxicity.
    5. A 90-day hamster feeding study with a NOAEL of 5,000 ppm [328
mg/kg/day] and a LOAEL of 10,000 ppm [650 mg/kg/day] based on decreased
body weight gains and increased liver weights in both sexes.
    6. A 21-day rat dermal study with a NOAEL of 1,000 mg/kg/day, the
highest dose tested [HDT].
    7. A 1-year dog chronic feeding study with a NOAEL of 0.5 mg/kg/day
and a LOAEL of 5 mg/kg/day based on changes in liver function and
morphology in males.
    8. A rat chronic feeding / carcinogenicity study with a NOAEL for
systemic toxicity of 500 ppm [23.1 mg/kg/day in males and 30.1 mg/kg/
day in females] and a LOAEL for systemic toxicity of 2,500 ppm [117.9
mg/kg/day in males and 162.8 mg/kg/day in females] based on decreased
body weight gain, decreased food consumption, increased liver weights,
and increased hepatic clear cell areas and increased ALT levels in
females. Based on the incidence of Leydig cell tumors of the testes in
males, tralkoxydim was considered to have a positive carcinogenic
response.
    9. A 3-generation rat reproduction study with a parental systemic
NOAEL of 200 ppm [20 mg/kg/day] and a systemic LOAEL of 1,000 ppm [100
mg/kg/day] based on reduced body weights and body weight gains in
females. No reproductive toxicity was observed. The developmental NOAEL
of 200 ppm and a LOAEL of 1,000 ppm based on decreased mean pup weights
(F1a and F3a) and pup weight gains (F2a).
    10. A rat developmental study with a maternal NOAEL of 30 mg/kg/day
and with a maternal LOAEL of 200 mg/kg/day based on maternal mortality,
reduced body weights, and reduced food consumption and a developmental
NOAEL of 30 mg/kg/day and a developmental LOAEL of 200 mg/kg/day based
on reduced ossification of the centrum and hemicentrum, centrum
bipartite, misshapen centra and fused centra.
    11. A rabbit developmental study with a maternal NOAEL of 20 mg/kg/
day and a maternal LOAEL of 100 mg/kg/day based on reduced food
consumption and a developmental NOAEL of 20 mg/kg/day and a
developmental LOAEL of 100 mg/kg/day based on abortions and increases
in late resorptions.
    12. Tralkoxydim was negative for mutagenic/genotoxic effects in a
Gene mutation Ames Assay in bacteria, a forward gene mutation in mouse
lymphoma cells in culture, chromosome damage/In vitro assay in human
lymphocyte cells, DNA damage repair in vivo assay in rat hepatocytes,
and chromosome damage in vivo mouse micronuclei.
    13. Based on the results of the hamster and rat metabolism studies,
tralkoxydim was readily absorbed and excreted within 24 and 48 hours
after dosing, respectively. In hamsters, the metabolic profile in urine
was similar for males and females; no unchanged tralkoxydim was
detected and two major metabolites were identified: tralkoxydim acid
and tralkoxydim acid oxazole. The metabolic profile in the urine of
rats included two additional metabolites, tralkoxydim alcohol and
tralkoxydim diol.
    14. Several mechanistic studies and subchronic feeding studies were
submitted to support the selection of hamster in preference to the
mouse in assessing the carcinogenic potential of tralkoxydim. The
submitted data indicate that of all the species tested only the mouse
is susceptible to porphydrin accumulation in the liver following
treatment with tralkoxydim. The mouse was considered an inappropriate
species to use for carcinogenicity testing of tralkoxydim because of
its distinctive method of metabolism. However, the submitted hamster
cancer study was unacceptable owing to unacceptably high mortality in
the females. An acceptable second species carcinogenicity study is
required.

B. Toxicological Endpoints

    1. Acute dietary toxicity. EPA has established an acute RfD for
tralkoxydim of 0.3 milligrams/kilogram/day (mg/kg/day). This RfD is
based on the NOAEL of 30 mg/kg/day established in the rat developmental
study and using an uncertainty factor of 100 based on 10 X for inter-
species extrapolation and 10X for intra-species variation.
    2. Short - and intermediate - term toxicity. EPA could not identify
any toxicological effects that could be attributable to short or
intermediate-term dietary exposure .
    3. Chronic toxicity. EPA has established the RfD for tralkoxydim at
0.005 mg/kg/day. This RfD is based on NOAEL of 0.5 mg/kg/day in the
chronic toxicity study in dogs with a 100-fold uncertainty factor to
account for inter-species extrapolation (10 x) and intra-species
variability (10 x).
    4. Carcinogenicity. The Health Effects Division Cancer Assessment
Review Committee has classified Tralkoxydim in accordance with the
Agency's Proposed Guidelines for Carcinogen Risk Assessment (April 10,
1996) as a "likely to be human carcinogen". This classification is
based on the following factors:
    i. Occurrence of benign Leydig cell tumors at all dose levels with
the incidences at the high dose exceeding the concurrent and historical
control range.
    ii. Lack of an acceptable carcinogenicity study in a second species
as required by Subdivision F Guidelines.
    iii. The relevance of the testicular tumors to human exposure can
not be discounted

C. Exposures and Risks

    1. From food and feed uses.  The proposed tolerances in or on the
raw agricultural commodities: barley grain, barley hay, wheat grain and
wheat hay at 0.02 ppm, and barley straw, wheat forage and wheat straw
at 0.05 ppm are the first to be established for tralkoxydim, 2-
(Cyclohexen-1-one, 2-[1-(ethoxyimino)propyl]-3-hydroxy-5-(2,4,6-
trimethylphenyl)-(9Cl). There is no reasonable expectation of residues
of tralkoxydim occurring in meat, milk, poultry, or eggs from its use
on wheat and barley. Risk assessments were conducted by EPA to assess
dietary exposures from tralkoxydim 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 one day or single exposure. An acute dietary risk assessment was
conducted for tralkoxydim based on the NOAEL of 30 mg/kg/day from the
rat developmental study. The acute dietary analysis using the DEEM
computer program estimates that the distribution of single-day
exposures utilizes 0.02% of acute RfD.
    ii. Chronic exposure and risk. The Reference Dose (RfD) for
Tralkoxydim is 0.005 mg/kg/day. This value is based on

[[Page 69197]]

the systemic NOAEL of 0.5 mg/kg/day in the dog chronic feeding study
with a 100-fold safety factor to account for interspecies extrapolation
(10x) and intraspecies variability (10x).
    A DEEM chronic exposure analysis was conducted using tolerance
levels for wheat and barley and assuming that 100% of the crop is
treated to estimate dietary exposure for the general population and 22
subgroups. The chronic analysis showed that exposures from the
tolerance level residues in or on wheat, and barley for children 1-6
years old (the subgroup with the highest exposure) would be 1.4% of the
Reference Dose (RfD). The exposure for the general U.S. population
would be less than 1% of the RfD.
    iii. A lifetime dietary carcinogenicity exposure analysis was
conducted for tralkoxydim using the proposed tolerances along with the
assumption of 100% of the crop treated and a Q* of 1.68 x 10-
2 (mg/kg/day)-1. A lifetime risk exposure
analysis was also conducted using the DEEM computer analysis. The
estimated cancer risk (5 x 10-7) is less than the level that
the Agency usually considers for negligible cancer risk estimates.
    2. From drinking water. Drinking water estimated concentrations
(DWECs) for surface water (parent tralkoxydim) were calculated by PRIZM
computer models to be an average of 9.1 parts per billion (ppb). the
DWECs for ground water based on the computer model SCI-GROW2 were
calculated to be an average of .016 ppb.
    3.  From non-dietary exposure. There are no non-food uses of
tralkoxydim currently registered under the Federal Insecticide,
Fungicide and Rodenticide Act, as amended. 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."
    EPA does not have, at this time, available data to determine
whether tralkoxydim has a common mechanism of toxicity with other
substances or how to include this pesticide in a cumulative risk
assessment. Tralkoxydim is structurally a cyclohexanedione. Unlike
other pesticides for which EPA has followed a cumulative risk approach
based on a common mechanism of toxicity, tralkoxydim does not appear to
produce a toxic metabolite produced by other substances. For the
purposes of these tolerances action, therefore, EPA has not assumed
that tralkoxydim has a common mechanism of toxicity with other
substances. For information regarding EPA's efforts to determine which
chemicals have a common mechanism of toxicity and to evaluate the
cumulative effects of such chemicals, see the 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. The acute dietary analysis based on the NOAEL of 30
mg/kg/day from the rat developmental study using the DEEM computer
program estimates that the distribution of single-day exposures
utilizes 0.02% of acute RfD. The drinking water level of comparisons
(DWLOCs) for acute exposure to tralkoxydim in drinking water calculated
for females 13+ years old was 9,000 ppb. The estimated average
concentration in surface water for tralkoxydim is 9 ppb. EPA's acute
drinking water level of comparison is well above the estimated
exposures for tralkoxydim in water for the subgroup of concern. For
groundwater, the estimated environmental concentrations (EEC's) using
the SCI-GROW model were all less than 1 ppb.
    2. Chronic risk. A DEEM chronic exposure analysis showed that
exposure from tolerance level residues in or on wheat, and barley for
children 1-6 years old (the subgroup with the highest exposure) would
be 1.4% of the Reference Dose (RfD). The exposure for the general U.S.
population would be less than 1% of the RfD. The drinking water level
of comparisons (DWLOCs) for chronic exposure to tralkoxydim in drinking
water calculated for U.S. population was 150 ppb and for children (1-6
years old) the DWLOC was 50 ppb. The estimated average concentration in
surface water for tralkoxydim is 9 ppb. EPA's chronic drinking water
level of concern is above the estimated exposures for tralkoxydim in
water for the U.S. population and the subgroup of concern. Conservative
model estimates (SCI-GROW) of the concentrations of tralkoxydim in
groundwater indicate that exposure will be minimal.
    3. Cancer risk. A DWLOC for cancer was calculated as 1 ppb. The
estimated concentration in surface water and groundwater for
tralkoxydim for chronic exposure are 0.9 ppb [2.8 ppb (the 56-day
concentration)/3] and 0.1 ppb, respectively. The model exposure
estimates are less than the cancer DWLOC.
    EPA concludes that there is a reasonable certainty that no harm
will result from aggregate exposure to tralkoxydim residues.

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

    Safety factor for infants and children. In assessing the potential
for additional sensitivity of infants and children to residues of
tralkoxydim, 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 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 pre- and post-natal toxicity and the
completeness of the database unless EPA determines that a different
margin of safety will be safe for infants and children. The Agency
concluded that an extra safety factor to protect infants and children
is not needed based on the following considerations:
    \ The toxicology data base is complete for the assessment of
special sensitivity of infants and children
    \ The developmental and reproductive toxicity data do not indicate
increase susceptibility of rats or rabbits to in utero and/or postnatal
exposure
    \ The NOAEL used in deriving the RfD is based on changes in liver
function and morphology in male adult dogs (not developmental or
neurotoxic effects) after chronic exposure and thus are not relevant
for enhanced sensitivity to infants and children
    \ Unrefined dietary exposure estimates (assuming all commodities
contain tolerance level residues) overestimate dietary exposure
    \ Model data used for ground and surface source drinking water
exposure assessments result in estimates considered to be upper-bound
concentrations
    \ There are no registered uses for tralkoxydim that could result in
residential exposures.
    EPA concludes that there is a reasonable certainty that no harm
will result to children from aggregate exposure to tralkoxydim
residues.

[[Page 69198]]

III. Other Considerations

A. Metabolism In Plants and Animals

    The nature of the residue in barley, wheat, rotational crops, and
livestock is adequately understood. The residues of concern for the
tolerance expression are parent per se. Based on the results of animal
metabolism studies it is unlikely that secondary residues would occur
in animal commodities from the use of tralkoxydim on wheat and barley.

B. Analytical Enforcement Methodology

    An adequate analytical method, gas chromatography/mass spectrometry
with selected ion monitoring, is available for enforcement purposes.
Because of the long lead time from establishing these tolerances to
publication of the enforcement methodology in the Pesticide Analytical
Manual, Vol. II, the analytical methodology is being made available in
the interim to anyone interested in pesticide enforcement when
requested from: Calvin Furlow, PRRIB, IRSD (7502C), Office of Pesticide
Programs, Environmental Protection Agency, 401 M St., SW., Washington,
DC 20460. Office location and telephone number: Rm 101FF, CM #2, 1921
Jefferson Davis Hwy., Arlington, VA 22202, (703-305-5229).

C. Endocrine Effects

    EPA is required to develop a screening program to determine whether
certain substances (including all pesticides and inerts) "may have an
effect in humans that is similar to an effect produced by a naturally
occurring estrogen, or such other effect ... " The Agency is
currently working with interested stakeholders, including other
government agencies, public interest groups, industry and research
scientists in developing a screening and testing program and a priority
setting scheme to implement this program. Congress has allowed 3 years
from the passage of FQPA (August 3, 1999) to implement this program. At
that time, EPA may require further testing of this active ingredient
and end use products for endocrine disrupter effects.

D. Magnitude of Residues

    Based on the results of animal metabolism studies it is unlikely
that significant residues would occur in secondary animal commodities
from the use of tralkoxydim on wheat and barley.
    The nature of the residue in plants is adequately understood for
the purposes of these time-limited tolerances.

E. International Residue Limits

    There are no Codex Alimentarius Commission (Codex) or Mexican
Maximum Residue Levels (MRLs) for tralkoxydim at this time.

F. Rotational Crop Restrictions.

    No tolerances for inadvertent residues of tralkoxydim are required
in rotational crops.

IV. Conclusion

    Due to the second species carcinogenicity study data gap: EPA
believes it is inappropriate to establish permanent tolerances for the
uses of tralkoxydim at this time. EPA believes that the existing data
support time-limited tolerances to February 28, 2003. Therefore, time-
limited tolerances are established for residues of the herbicide,
tralkoxydim, 2-(Cyclohexen-1-one, 2-[1-(ethoxyimino)propyl]-3-hydroxy-
5-(2,4,6-trimethylphenyl)-(9Cl), in or on the raw agricultural
commodities: barley grain, barley hay, wheat grain and wheat hay at
0.02 ppm, and barley straw, wheat forage and wheat straw at 0.05 ppm.
These time-limited tolerances will expire and be revoked on February
28, 2003.

V. 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 (l)(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 govern 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 February 16, 1999, 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) or a request for a fee waiver. If a hearing is requested,
the objections must include a statement of the factual issues on which
a hearing is requested, the requestor's contentions on such issues, and
a summary of any evidence relied upon by the requestor (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 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 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 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.

VI. Public Record and Electronic Submissions

    EPA has established a record for this rulemaking under docket
control number [OPP-300764] (including any comments and data submitted
electronically). A public version of this record, including printed,
paper versions of electronic comments, 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. 119 of the Public Information and Records
Integrity Branch, Information Resources and Services Division (7502C),
Office of Pesticide Programs, Environmental Protection Agency, CM #2,
1921 Jefferson Davis Highway, Arlington, VA.
    The official record for this rulemaking, as well as the public
version, as described above will be kept in paper form. Accordingly,
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 which
will also include all comments submitted directly in writing. The
official rulemaking record is the paper record maintained at the
Virginia

[[Page 69199]]

address in "ADDRESSES" at the beginning of this document.

VII. Regulatory Assessment Requirements

A. Certain Acts and Executive Orders

    This final rule establishes tolerances under FFDCA section 408(d)
in response to a petition submitted to the Agency. The Office of
Management and Budget (OMB) has exempted these types of actions from
review under Executive Order 12866, entitled Regulatory Planning and
Review (58 FR 51735, October 4, 1993). 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) (Pub. L. 104-4). Nor does
it require any special considerations as required by 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).
    In addition, since tolerances and exemptions that are established
on the basis of a petition under FFDCA section 408(d), such as the
tolerances 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. Nevertheless, the Agency has
previously assessed whether establishing tolerances, exemptions from
tolerances, raising tolerance levels or expanding exemptions might
adversely impact small entities and concluded, as a generic matter,
that there is no adverse economic impact. The factual basis for the
Agency's generic certification for tolerance actions published on May
4, 1981 (46 FR 24950) and was provided to the Chief Counsel for
Advocacy of the Small Business Administration.

B. Executive Order 12875

    Under Executive Order 12875, entitled Enhancing the
Intergovernmental Partnership (58 FR 58093, October 28, 1993), EPA may
not issue a regulation that is not required by statute and that creates
a mandate upon a State, local, or tribal government, unless the Federal
government provides the funds necessary to pay the direct compliance
costs incurred by those governments. If the mandate is unfunded, EPA
must provide to OMB a description of the extent of EPA's prior
consultation with representatives of affected State, local, and tribal
governments, the nature of their concerns, copies of any written
communications from the governments, and a statement supporting the
need to issue the regulation. In addition, Executive Order 12875
requires EPA to develop an effective process permitting elected
officials and other representatives of State, local, and tribal
governments "to provide meaningful and timely input in the development
of regulatory proposals containing significant unfunded mandates."
    Today's rule does not create an unfunded Federal mandate on State,
local, or tribal governments. The proposed rule does not impose any
enforceable duties on these entities. Accordingly, the requirements of
section 1(a) of Executive Order 12875 do not apply to this rule.

C. Executive Order 13084

    Under Executive Order 13084, entitled Consultation and Coordination
with Indian Tribal Governments (63 FR 27655, May 19, 1998), EPA may not
issue a regulation that is not required by statute, that significantly
or uniquely affects the communities of Indian tribal governments, and
that imposes substantial direct compliance costs on those communities,
unless the Federal government provides the funds necessary to pay the
direct compliance costs incurred by the tribal governments. If the
mandate is unfunded, EPA must provide to OMB, in a separately
identified section of the preamble to the rule, a description of the
extent of EPA's prior consultation with representatives of affected
tribal governments, a summary of the nature of their concerns, and a
statement supporting the need to issue the regulation. In addition,
Executive Order 13084 requires EPA to develop an effective process
permitting elected officials and other representatives of Indian tribal
governments "to provide meaningful and timely input in the development
of regulatory policies on matters that significantly or uniquely affect
their communities."
    Today's rule does not significantly or uniquely affect the
communities of Indian tribal governments. This action does not involve
or impose any requirements that affect Indian tribes. Accordingly, the
requirements of section 3(b) of Executive Order 13084 do not apply to
this rule.

VIII. 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 the 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 record
keeping requirements.

    Dated: December 3, 1998.

Stephen L. Johnson,
Acting Director, 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. 346a and 371.

    2. By adding Sec. 180.548, to read as follows:

Sec. 180.548  Tralkoxydim; tolerances for residues.

    (a) General. Time-limited tolerances are established for residues
of the herbicide, tralkoxydim, 2-(Cyclohexen-1-one, 2-[1-
(ethoxyimino)propyl]-3-hydroxy-5-(2,4,6-trimethylphenyl)-(9Cl) in or on
the raw agricultural commodities:

-------------------------------------------------------------------
                                                    Expiration/
       Commodity            Parts per million     Revocation Date
-------------------------------------------------------------------
Barley, grain...................  0.02                2/28/03
Barley, hay.....................  0.02                2/28/03
Barley, straw...................  0.05                2/28/03
Wheat, forage...................  0.05                2/28/03
Wheat, grain....................  0.02                2/28/03
Wheat, hay......................  0.02                2/28/03
Wheat, straw....................  0.05                2/28/03
-------------------------------------------------------------------

    (b) Section 18 emergency exemptions. [Reserved]

[[Page 69200]]

    (c) Tolerances with regional registrations. [Reserved]
    (d) Indirect or inadvertent residues. [Reserved]

[FR Doc. 98-33121 Filed 12-15-98; 8:45 am]
BILLING CODE 6560-50-F