Hexythiazox; Pesticide Tolerances for Emergency Exemptions

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

[Federal Register: November 10, 2004 (Volume 69, Number 217)]
[Rules and Regulations]
[Page 65073-65081]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr10no04-7]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-2004-0329; FRL-7684-2]

AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.

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SUMMARY: This regulation establishes time-limited tolerances for
combined residues of hexythiazox (trans-5-(4-chlorophenyl)-N-
cyclohexyl-4-methyl-2-oxothiazolidine-3-carboxamide) and its
metabolites containing the (4-chlorophenyl)-4-methyl-2-oxo-3-
thiazolidine moiety in or on field corn grain, stover, and fodder. This
action is in response to EPA's granting of an emergency exemption under
section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act
(FIFRA) authorizing use of the pesticide on field corn. This regulation
establishes maximum permissible levels for residues of hexythiazox in
these food commodities. The tolerances will expire and are revoked on
December 31, 2007.

DATES: This regulation is effective November 10, 2004. Objections and
requests for hearings must be received on or before January 10, 2005.

ADDRESSES: To submit a written objection or hearing request follow the
detailed instructions as provided in Unit VII. of the SUPPLEMENTARY
INFORMATION. EPA has established a docket for this action under docket
identification (ID) number OPP-2004-0329. All documents in the docket
are listed in the EDOCKET index at http://www.epa.gov/edocket. Although
listed in the index, some information is not publicly available, i.e.,
CBI or other information whose disclosure is restricted by statute.
Certain other material, such as copyrighted material, is not placed on
the Internet and will be publicly available only in hard copy form.
Publicly available docket materials are available either electronically
in EDOCKET or in hard copy at the Public Information and Records
Integrity Branch (PIRIB), Rm. 119, Crystal Mall #2, 1801 S. Bell St.,

[[Page 65074]]

Arlington, VA. This docket facility is open from 8:30 a.m. to 4 p.m.,
Monday through Friday, excluding legal holidays. The docket telephone
number is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: Andrew Ertman, Registration Division
(7505C), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone
number: (703) 308-9367; e-mail address: sec-18-mailbox@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 affected entities may include, but are not limited to:
? Crop production (NAICS 111)
? Animal production (NAICS 112)
? Food manufacturing (NAICS 311)
? Pesticide manufacturing (NAICS 32532)
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 this unit could also be
affected. The North American Industrial Classification System (NAICS)
codes have been provided to assist you and others in determining
whether this action might apply to certain entities. If you have any
questions regarding the applicability of this action to a particular
entity, consult the person listed under FOR FURTHER INFORMATION CONTACT.

B. How Can I Access Electronic Copies of this Document and Other
Related Information?

In addition to using EDOCKET (http://www.regulations.gov/), you may
access this Federal Register document electronically through the EPA
Internet under the ``Federal Register'' listings at http://www.epa.gov/
fedrgstr/. A frequently updated electronic version of 40 CFR part 180
is available at E-CFR Beta Site Two at http://www.gpoaccess.gov/ecfr/.

II. Background and Statutory Findings

EPA, on its own initiative, in accordance with sections 408(e) and
408(1)(6) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21
U.S.C. 346a, is establishing tolerances for combined residues of
hexythiazox (trans-5-(4-chlorophenyl)-N-cyclohexyl-4-methyl-2-
oxothiazolidine-3-carboxamide) and its metabolites containing the (4-
chlorophenyl)-4-methyl-2-oxo-3-thiazolidine moiety in or on corn,
field, grain at 0.05 ppm; corn, field, forage at 2.0 ppm; and corn,
field, stover at 2.0 ppm. These tolerances will expire and are revoked
on December 31, 2007. EPA will publish a document in the Federal
Register to remove the revoked tolerances 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 of the FFDCA and the new safety standard to
other tolerances and exemptions. Section 408(e) of the FFDCA allows EPA
to establish a tolerance or an exemption from the requirement of a
tolerance on its own initiative, i.e., without having received any
petition from an outside party.
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) of the FFDCA 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) of the FFDCA 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 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 of 1996
(FQPA). EPA has established regulations governing such emergency
exemptions in 40 CFR part 166.

III. Emergency Exemption for Hexythiazox on Corn and FFDCA Tolerances

The applicant stated that the development of resistance in spider
mite populations to the standard acaricide used to control mites has
created an urgent and non-routine situation. EPA has authorized under
FIFRA section 18 the use of hexythiazox on corn for control of Banks
grass mite and two-spotted spider mite in Texas. After having reviewed
the submission, EPA concurs that emergency conditions exist for this State.
As part of its assessment of this emergency exemption, EPA assessed
the potential risks presented by residues of hexythiazox in or on field
corn grain, stover, and fodder. In doing so, EPA considered the safety
standard in section 408(b)(2) of the FFDCA, and EPA decided that the
necessary tolerance under section 408(l)(6) of the FFDCA 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 these tolerances
without notice and opportunity for public comment as provided in
section 408(l)(6) of the FFDCA. Although these tolerances will expire
and are revoked on December 31, 2007, under section 408(l)(5) of the
FFDCA, residues of the pesticide not in excess of the amounts specified
in the tolerances remaining in or on field corn grain, stover, and
fodder 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 levels that were authorized by these tolerances at the time
of that application. EPA will take action to revoke these tolerances
earlier if any experience with, scientific data on, or other relevant
information on this pesticide indicate that the residues are not safe.
Because these tolerances are being approved under emergency
conditions, EPA has not made any decisions about whether hexythiazox
meets EPA's registration requirements for use on corn or whether
permanent tolerances for this use would be appropriate. Under these
circumstances, EPA does not believe that these tolerances serve as a
basis for registration of hexythiazox by a State for special local
needs under FIFRA section 24(c). Nor do these tolerances serve as the
basis for any State other than Texas to use this pesticide on this crop
under section 18 of FIFRA without following all

[[Page 65075]]

provisions of EPA's regulations implementing FIFRA section 18 as
identified in 40 CFR part 166. For additional information regarding the
emergency exemption for hexythiazox, 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 of the FFDCA 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) of the FFDCA, 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
hexythiazox and to make a determination on aggregate exposure,
consistent with section 408(b)(2) of the FFDCA, for time-limited
tolerances for combined residues of hexythiazox (trans-5-(4-
chlorophenyl)-N-cyclohexyl-4-methyl-2-oxothiazolidine-3-carboxamide)
and its metabolites containing the (4-chlorophenyl)-4-methyl-2-oxo-3-
thiazolidine moiety in or on corn, field, grain at 0.05 ppm; corn,
field, forage at 2.0 ppm; and corn, field, stover at 2.0 ppm. EPA's
assessment of the dietary exposures and risks associated with
establishing the tolerance follows.

A. Toxicological Endpoints

The dose at which no observed adverse effect level (the NOAEL) from
the toxicology study identified as appropriate for use in risk
assessment is used to estimate the toxicological endpoint. However, the
lowest dose at which adverse effects of concern are identified (the
lowest observed adverse effect level (LOAEL)) is sometimes used for
risk assessment if NOAEL was achieved in the toxicology study selected.
An uncertainty factor (UF) is applied to reflect uncertainties inherent
in the extrapolation from laboratory animal data to humans and in the
variations in sensitivity among members of the human population as well
as other unknowns. An UF of 100 is routinely used, 10X to account for
interspecies differences and 10X for intraspecies differences.
For dietary risk assessment (other than cancer) the Agency uses the
UF to calculate an acute or chronic reference dose (aRfD or cRfD) where
the RfD is equal to the NOAEL divided by the appropriate UF (RfD =
NOAEL/UF). Where an additional safety factor is retained due to
concerns unique to the FQPA, this additional factor is applied to the
RfD by dividing the RfD by such additional factor. The acute or chronic
Population Adjusted Dose (aPAD or cPAD) is a modification of the RfD to
accommodate this type of FQPA SF.
For non-dietary risk assessments (other than cancer) the UF is used
to determine the level of concern (LOC). For example, when 100 is the
appropriate UF (10X to account for interspecies differences and 10X for
intraspecies differences) the LOC is 100. To estimate risk, a ratio of
the NOAEL to exposures (margin of exposure (MOE) = NOAEL/exposure) is
calculated and compared to the LOC.
The linear default risk methodology (Q*) is the primary method
currently used by the Agency to quantify carcinogenic risk. The Q*
approach assumes that any amount of exposure will lead to some degree
of cancer risk. A Q* is calculated and used to estimate risk which
represents a probability of occurrence of additional cancer cases
(e.g., risk is expressed as 1 x10-6 or one in a million).
Under certain specific circumstances, MOE calculations will be used for
the carcinogenic risk assessment. In this non-linear approach, a
``point of departure'' is identified below which carcinogenic effects
are not expected. The point of departure is typically a NOAEL based on
an endpoint related to cancer effects though it may be a different
value derived from the dose response curve. To estimate risk, a ratio
of the point of departure to exposure (MOE_cancer = point of
departure/exposures) is calculated.

Table 1.--Summary of Toxicological Dose and Endpoints for Hexythiazox for Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
Dose Used in Risk FQPA SF and Endpoint Study and Toxicological
Exposure Scenario Assessment, UF for Risk Assessment Effects
----------------------------------------------------------------------------------------------------------------
Acute dietary females (13-50 years of Developmental NOAEL = FQPA SF = 1X Developmental toxicity
age) 240 mg/kg/day aPAD= acute RfD/FQPA study - rat
UF = 100............... SF = 2.4 mg/kg/day. Developmental LOAEL =
Acute RfD = 2.4 mg/kg/ 720 mg/kg/day based on
day. delayed ossification
----------------------------------------------------------------------------------------------------------------
Acute dietary (general population A dose and endpoint attributable to a single exposure were not identified
including infants and children) from the available oral toxicity studies, including maternal toxicity in
the developmental toxicity studies.
----------------------------------------------------------------------------------------------------------------
Chronic dietary (all populations) NOAEL= 2.5 mg/kg/day FQPA SF = 1X One-Year toxicity
UF = 100 chronic....... cPAD= chronic RfD/FQPA feeding study - dog
RfD= 0.025 mg/kg/day... SF = 0.025 mg/kg/day. LOAEL = 12.5 mg/kg/day
based on increased
absolute and relative
adrenal weights and
associated adrenal
histopathology
----------------------------------------------------------------------------------------------------------------
Cancer (oral, dermal, inhalation) Category C (possible Q1* = 2.22 x 10-2 Increases in incidence
human carcinogen) of malignant and
combined benign/
malignant liver tumors
in mice
----------------------------------------------------------------------------------------------------------------

[[Page 65076]]

B. Exposure Assessment

1. Dietary exposure from food and feed uses. Tolerances have been
established (40 CFR 180.448) for the combined of hexythiazox, in or on
a variety of raw agricultural commodities. Risk assessments were
conducted by EPA to assess dietary exposures from hexythiazox in food
as follows:
i. Acute exposure. 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 Dietary Exposure Evaluation Model
(DEEMTM) analysis evaluated the individual food consumption
as reported by respondents in the United States Department of
Agriculture (USDA) 1994-1996, and 1998 nationwide Continuing Surveys of
Food Intake by Individuals (CSFII) and accumulated exposure to the
chemical for each commodity. Published and proposed tolerance level
residues were used. Default and specially assigned processing factors
were assumed for all commodities.
ii. Chronic exposure. In conducting this chronic dietary risk
assessment, the DEEMTM analysis evaluated the individual
food consumption as reported by respondents in the USDA 1994-1996, and
1998 nationwide CSFII and accumulated exposure to the chemical for each
commodity. The following assumptions were made for the chronic exposure
assessments: Partially refined, deterministic assessment using
tolerance-level residue or anticipated residues, average weighted
percent crop treated (% CT) information and modified DEEMTM
(version 2.0) processing factors for some commodities based on
guideline processing studies.
iii. Cancer. The Agency believes that pesticidal use of hexythiazox
is likely to pose a carcinogenic hazard to humans. Thus, a cancer
dietary risk assessment is required. Hexythiazox was classified by the
Agency as a ``Group C'' - possible human carcinogen-chemical. It has
been assigned a Q1* = 2.22 x 10-2 milligrams/kilogram/day
(mg/kg/day) for purposes of risk assessment. The estimated exposure of
the U.S. population (total) to hexythiazox is 3.0 x 10-5 mg/kg/day.
iv. Anticipated residue and PCT information. Section 408(b)(2)(E)
of the FFDCA authorizes EPA to use available data and information on
the anticipated residue levels of pesticide residues in food and the
actual levels of pesticide chemicals that have been measured in food.
If EPA relies on such information, EPA must require that data be
provided 5 years after the tolerance is established, modified, or left
in effect, demonstrating that the levels in food are not above the
levels anticipated. Following the initial data submission, EPA is
authorized to require similar data on a time frame it deems
appropriate. As required by section 408(b)(2)(E) of the FFDCA, EPA will
issue a Data Call-In for information relating to anticipated residues
to be submitted no later than 5 years from the date of issuance of this
tolerance.
Section 408(b)(2)(F) of the FFDCA states that the Agency may use
data on the actual percent of food treated for assessing chronic
dietary risk only if the Agency can make the following findings:
Condition 1, that the data used are reliable and provide a valid basis
to show what percentage of the food derived from such crop is likely to
contain such pesticide residue; Condition 2, that the exposure estimate
does not underestimate exposure for any significant subpopulation
group; and Condition 3, if data are available on pesticide use and food
consumption in a particular area, the exposure estimate does not
understate exposure for the population in such area. In addition, the
Agency must provide for periodic evaluation of any estimates used. To
provide for the periodic evaluation of the estimate of PCT as required
by section 408(b)(2)(F) of the FFDCA, EPA may require registrants to
submit data on PCT.
The Agency used PCT information as follows:
Almond nutmeat, 2%; pecans, < 1%; other nutmeat, < 1%; almond hulls,
2%; apricots, 2%; cherries, < 1%; peaches, 1%; nectarines, 2%; plum, 1%;
plum, prune, fresh, < 1%; plum, prune, dried, < 1%; caneberry crop
subgroup, 15%; spearmint tops, 5%; peppermint, tops, 5%; undelinted
cottonseed, 1%; cottonseed meal, 1%; refined cottonseed oil, 1%;
apples, 4%; apple juice, 4%; wet apple pomace, 4%; pears, 3%; hops,
45%; dates, 45%; strawberries, 14%.
The Agency believes that the three conditions listed above have
been met. With respect to Condition 1, PCT estimates are derived from
Federal and private market survey data, which are reliable and have a
valid basis. EPA uses a weighted average PCT for chronic dietary
exposure estimates. This weighted average PCT figure is derived by
averaging State-level data for a period of up to 10 years, and
weighting for the more robust and recent data. A weighted average of
the PCT reasonably represents a person's dietary exposure over a
lifetime, and is unlikely to underestimate exposure to an individual
because of the fact that pesticide use patterns (both regionally and
nationally) tend to change continuously over time, such that an
individual is unlikely to be exposed to more than the average PCT over
a lifetime. For acute dietary exposure estimates, EPA uses an estimated
maximum PCT. The exposure estimates resulting from this approach
reasonably represent the highest levels to which an individual could be
exposed, and are unlikely to underestimate an individual's acute
dietary exposure. The Agency is reasonably certain that the percentage
of the food treated is not likely to be an underestimation. As to
Conditions 2 and 3, regional consumption information and consumption
information for significant subpopulations is taken into account
through EPA's computer-based model for evaluating the exposure of
significant subpopulations including several regional groups. Use of
this consumption information in EPA's risk assessment process ensures
that EPA's exposure estimate does not understate exposure for any
significant subpopulation group and allows the Agency to be reasonably
certain that no regional population is exposed to residue levels higher
than those estimated by the Agency. Other than the data available
through national food consumption surveys, EPA does not have available
information on the regional consumption of food to which hexythiazox
may be applied in a particular area.
2. Dietary exposure from drinking water. The Agency lacks
sufficient monitoring exposure data to complete a comprehensive dietary
exposure analysis and risk assessment for hexythiazox in drinking
water. Because the Agency does not have comprehensive monitoring data,
drinking water concentration estimates are made by reliance on
simulation or modeling taking into account data on the physical
characteristics of hexythiazox.
The Agency uses the Generic Estimated Environmental Concentration
(GENEEC) or the Pesticide Root Zone/Exposure Analysis Modeling System
(PRZM/EXAMS) to estimate pesticide concentrations in surface water and
SCI-GROW, which predicts pesticide concentrations in ground water. In
general, EPA will use GENEEC (a Tier 1 model) before using PRZM/EXAMS
(a Tier 2 model) for a screening-level assessment for surface water.
The GENEEC model is a subset of the PRZM/EXAMS model that uses a
specific high-end runoff scenario for pesticides. GENEEC incorporates a
farm pond scenario, while PRZM/EXAMS incorporate an index reservoir
environment in place of the previous

[[Page 65077]]

pond scenario. The PRZM/EXAMS model includes a percent crop (PC) area
factor as an adjustment to account for the maximum PC coverage within a
watershed or drainage basin.
None of these models include consideration of the impact processing
(mixing, dilution, or treatment) of raw water for distribution as
drinking water would likely have on the removal of pesticides from the
source water. The primary use of these models by the Agency at this
stage is to provide a coarse screen for sorting out pesticides for
which it is highly unlikely that drinking water concentrations would
ever exceed human health levels of concern.
Since the models used are considered to be screening tools in the
risk assessment process, the Agency does not use estimated
environmental concentrations (EECs) from these models to quantify
drinking water exposure and risk as a %RfD or %PAD. Instead drinking
water levels of comparison (DWLOCs) are calculated and used as a point
of comparison against the model estimates of a pesticide's
concentration in water. DWLOCs are theoretical upper limits on a
pesticide's concentration in drinking water in light of total aggregate
exposure to a pesticide in food, and from residential uses. Since
DWLOCs address total aggregate exposure to hexythiazox, they are
further discussed in the aggregate risk sections below.
Based on the GENEEC and SCI-GROW models, the EECs of hexythiazox
for acute exposures are estimated to be 1.81 parts per billion (ppb)
for surface water and 0.009 ppb for ground water. The EECs for chronic
exposures are estimated to be 0.91 ppb for surface water and 0.009 ppb
for ground water.
3. From non-dietary exposure. The term ``residential exposure'' is
used in this document to refer to non-occupational, non-dietary
exposure (e.g., for lawn and garden pest control, indoor pest control,
termiticides, and flea and tick control on pets).
Hexythiazox is not registered for use on any sites that would
result in residential exposure.
4. Cumulative exposure to substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) of the FFDCA 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 hexythiazox 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,
hexythiazox 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 hexythiazox 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).

C. Safety Factor for Infants and Children

1. In general. Section 408 of the FFDCA 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 on toxicity and exposure
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 MOE analysis or
through using uncertainty (safety) factors in calculating a dose level
that poses no appreciable risk to humans.
2. Developmental toxicity studies--a. rats. In the rat
developmental study, the maternal (systemic) NOEL was 240 mg/kg/day.
The maternal LOEL of 720 mg/kg/day was based on decreased food
consumption and decreased body weight. The developmental (fetal) NOEL
was 240 mg/kg/day. The developmental LOEL was based on slight delayed
ossification.
b. Rabbits. In the rabbit developmental toxicity study, the
maternal (systemic) NOEL was 1,080 mg/kg/day at the highest dose tested
(HDT). The developmental (fetal) NOEL was 1,080 mg/kg/day at the HDT.
3. Reproductive toxicity study--rats. In the 2-generation
reproductive toxicity study in rats, the parental (systemic) NOEL was
20 mg/kg/day. The LOEL of 120 mg/kg/day was based on decreased body
weight and decreased food consumption. The developmental NOEL was 20
mg/kg/day. The developmental LOEL of 120 mg/kg/day was based on
decreased body weight and delayed maturation. The reproductive NOEL was
120 mg/kg/day at the HDT.
4. Prenatal and postnatal sensitivity. The prenatal and postnatal
toxicology data base for hexythiazox is complete with respect to
current toxicological data requirements. There are no prenatal or
postnatal toxicity concerns for infants and children, based on the
results of the rat and rabbit developmental toxicity studies and the 2-
generation rat reproductive toxicity study. In the developmental study
in rats, the developmental NOEL and LOEL is the same as the maternal
NOEL and LOEL demonstrating that no extra-sensitivity for infants and
children is present. In rabbits, there are no maternal or developmental
effects up to the limit dose of 1,080 mg/kg/day HDT. In the 2-
generation reproductive toxicity study in rats, there are no pup
effects at doses below maternal effects and the common effects in both
pups and parental animals decreased body weight also demonstrates that
there is no extra-sensitivity for infants and children.
5. Conclusion. Based on the above, EPA concludes that reliable data
support use of the standard 100-fold uncertainty factor and that the
10x FQPA safety factor be removed since the hazard and exposure
assessments do not indicate a concern for potential risk to infants and
children.

D. Aggregate Risks and Determination of Safety

To estimate total aggregate exposure to a pesticide from food,
drinking water, and residential uses, the Agency calculates DWLOCs
which are used as a point of comparison against the model estimates of
a pesticide's concentration in water (EECs). DWLOC values are not
regulatory standards for drinking water. DWLOCs are theoretical upper
limits on a pesticide's concentration in drinking water in light of
total aggregate exposure to a pesticide in food and residential uses.
In calculating a DWLOC, the Agency determines how much of the
acceptable exposure (i.e., the PAD) is available for exposure through
drinking water e.g., allowable chronic water exposure (mg/kg/day) =
cPAD - (average food + chronic non-dietary, non-occupational exposure).
This allowable exposure through drinking water is used to calculate a
DWLOC.
A DWLOC will vary depending on the toxic endpoint, drinking water
consumption, and body weights. Default body weights and consumption
values as used by the USEPA Office of Water are used to calculate
DWLOCs: 2 liter (L)/70 kg (adult male), 2L/60 kg (adult female), and
1L/10 kg (child). Default body weights and drinking water consumption
values vary on an individual basis. This variation will be

[[Page 65078]]

taken into account in more refined screening-level and quantitative
drinking water exposure assessments. Different populations will have
different DWLOCs. Generally, a DWLOC is calculated for each type of
risk assessment used: Acute, short-term, intermediate-term, chronic,
and cancer.
When EECs for surface water and ground water are less than the
calculated DWLOCs, EPA concludes with reasonable certainty that
exposures to hexythiazox in drinking water (when considered along with
other sources of exposure for which EPA has reliable data) would not
result in unacceptable levels of aggregate human health risk at this
time. Because EPA considers the aggregate risk resulting from multiple
exposure pathways associated with a pesticide's uses, levels of
comparison in drinking water may vary as those uses change. If new uses
are added in the future, EPA will reassess the potential impacts of
hexythiazox on drinking water as a part of the aggregate risk
assessment process.
1. Acute risk. Using the exposure assumptions discussed in this
unit for acute exposure, the acute dietary exposure from food to
hexythiazox will occupy 0.12 of the aPAD for females 13-49 years old,
the population sub-group of concern. In addition, despite the potential
for acute dietary exposure to hexythiazox in drinking water, after
calculating DWLOCs and comparing them to conservative model EECs of
hexythiazox in surfacewater and ground water, EPA does not expect the
aggregate exposure to exceed 100% of the aPAD, as shown in the
following Table 2:

Table 2.--Aggregate Risk Assessment for Acute Exposure to Hexythiazox
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup aPAD (mg/ % aPAD Water EEC Water EEC Acute DWLOC
kg) (Food) (ppb) (ppb) (ppb)
----------------------------------------------------------------------------------------------------------------
Females (13-49 years old) 2.4 0.12 1.81 0.009 72,000
----------------------------------------------------------------------------------------------------------------

2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that exposure to
hexythiazox from food will utilize 0.1% of the cPAD for the U.S.
population, 0.2% of the cPAD for all infants, and 0.4% of the cPAD for
children 1-5 years old. There are no residential uses for hexythiazox
that result in chronic residential exposure to hexythiazox. In
addition, despite the potential for chronic dietary exposure to
hexythiazox in drinking water, after calculating DWLOCs and comparing
them to conservative model EECs of hexythiazox in surface water and
ground water, EPA does not expect the aggregate exposure to exceed 100%
of the cPAD, as shown in the following Table 3:

Table 3.--Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Hexythiazox
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup cPAD mg/kg/ % cPAD Water EEC Water EEC Chronic
day (Food) (ppb) (ppb) DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
General U.S. population 0.025 0.1 0.910 0.009 870
----------------------------------------------------------------------------------------------------------------
All Infants (< 1 year old) 0.025 0.2 0.910 0.009 250
----------------------------------------------------------------------------------------------------------------
Children (1-2 years old) 0.025 0.4 0.910 0.009 250
----------------------------------------------------------------------------------------------------------------
Females (13-49 years old) 0.025 0.1 0.910 0.009 750
----------------------------------------------------------------------------------------------------------------
Youth (13-19 years old) 0.025 0.1 0.910 0.009 750
----------------------------------------------------------------------------------------------------------------
Adults (20-49 years old) 0.025 0.1 0.910 0.009 870
----------------------------------------------------------------------------------------------------------------

3. Short-term risk. Short-term aggregate exposure takes into
account residential exposure plus chronic exposure to food and water
(considered to be a background exposure level).
Hexythiazox is not registered for use on any sites that would
result in residential exposure. Therefore, the aggregate risk is the
sum of the risk from food and water, which were previously addressed.
4. Intermediate-term risk. Intermediate-term aggregate exposure
takes into account non-dietary, non-occupational exposure plus chronic
exposure to food and water (considered to be a background exposure level).
Hexythiazox is not registered for use on any sites that would
result in residential exposure. Therefore, the aggregate risk is the
sum of the risk from food and water, which were previously addressed.
5. Aggregate cancer risk for U.S. population. Chronic (cancer)
aggregate risk estimates are below the Agency's level of concern. A
partially refined analysis was performed using anticipated residue
levels for most crops, processing factors where applicable, and PCT or
anticipated market share information for all crops. The chronic cancer
analysis applied to the U.S. population only. The carcinogenic risk
estimate (food only) for the general U.S. population was 6.6 x
10-7. The Agency's level of concern is for risks that exceed
1 x 10-6. Thus, the estimated dietary cancer risk to the
U.S. population associated with the existing and pending uses is below
the level the Agency generally considers negligible for excess lifetime
cancer risk.
The surface water and ground water EECs were used to compare
against back-calculated DWLOCs for aggregate risk assessments. For the
carcinogenic risk scenario, the DWLOC is 3.675 ppb for the U.S
population. For ground water and surface water, the EECs for
hexythiazox are less than EPA's DWLOCs for hexythiazox in drinking
water as a contribution to carcinogenic aggregate exposure. Therefore,
EPA concludes with reasonable certainty that residues of hexythiazox in
drinking water do not contribute significantly to

[[Page 65079]]

the carcinogenic aggregate human- health risk at the present time.
6. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to the general population, and to infants and children from aggregate
exposure to hexythiazox residues.

V. Other Considerations

A. Analytical Enforcement Methodology

Adequate enforcement methodology (example--gas chromatography) is
available to enforce the tolerance expression. The method may be
requested from: Chief, Analytical Chemistry Branch, Environmental
Science Center, 701 Mapes Rd., Ft. Meade, MD 20755-5350; telephone
number: (410) 305-2905; e-mail address: residuemethods@epa.gov.

B. International Residue Limits

There are no international residues limits for hexythiazox on field
corn, and therefore, this is not an issue.

VI. Conclusion

Therefore, the tolerances are established for combined residues of
hexythiazox (trans-5-(4-chlorophenyl)-N-cyclohexyl-4-methyl-2-
oxothiazolidine-3-carboxamide) and its metabolites containing the (4-
chlorophenyl)-4-methyl-2-oxo-3-thiazolidine moiety in or on corn,
field, grain at 0.05 ppm; corn, field, forage at 2.0 ppm; and corn,
field, stover at 2.0 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, EPA will continue to use those procedures, with
appropriate adjustments, until the necessary modifications can be made.
The new section 408(g) of the FFDCA 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)
of the FFDCA, as was provided in the old sections 408 and 409 of the
FFDCA. 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 identification (ID) number OPP-2004-0329 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 January 10, 2005.
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 (1900L),
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460-0001. You may also deliver your request to the
Office of the Hearing Clerk in Suite 350, 1099 14th St., NW.,
Washington, DC 20005. 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) 564-6255.
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, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001.
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, 1200 Pennsylvania
Ave., NW., Washington, DC 20460-0001.
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 ADDRESSES. Mail your
copies, identified by the docket ID number OPP-2004-0329, to: Public
Information and Records Integrity Branch, Information Resources and
Services Division (7502C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001. In person or by courier, bring a copy to the location of the
PIRIB described in ADDRESSES. You may also send an electronic copy of
your request via e-mail to: opp-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 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).

[[Page 65080]]

VIII. Statutory and Executive Order Reviews

This final rule establishes time-limited tolerances 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). Because this rule has been exempted from review under Executive
Order 12866 due to its lack of significance, this rule is not subject
to Executive Order 13211, Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355,
May 22, 2001). 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 any special considerations 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 OMB review or any Agency action under Executive Order 13045,
entitled Protection of Children from Environmental Health Risks and
Safety Risks (62 FR 19885, April 23, 1997). 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). Since
tolerances and exemptions that are established on the basis of a FIFRA
section 18 exemption under section 408 of the FFDCA, 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. In addition, 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 13132,
entitled Federalism (64 FR 43255, August 10, 1999). Executive Order
13132 requires EPA to develop an accountable process to ensure
``meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications.''
``Policies that have federalism implications'' is defined in the
Executive Order to include regulations that have ``substantial direct
effects on the 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.'' This final
rule 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 section 408(n)(4) of the
FFDCA. For these same reasons, the Agency has determined that this rule
does not have any ``tribal implications'' as described in Executive
Order 13175, entitled Consultation and Coordination with Indian Tribal
Governments (59 FR 22951, November 6, 2000). Executive Order 13175,
requires EPA to develop an accountable process to ensure ``meaningful
and timely input by tribal officials in the development of regulatory
policies that have tribal implications.'' ``Policies that have tribal
implications'' is defined in the Executive Order to include regulations
that have ``substantial direct effects on one or more Indian tribes, on
the relationship between the Federal Government and the Indian tribes,
or on the distribution of power and responsibilities between the
Federal Government and Indian tribes.'' This rule will not have
substantial direct effects on tribal governments, on the relationship
between the Federal Government and Indian tribes, or on the
distribution of power and responsibilities between the Federal
Government and Indian tribes, as specified in Executive Order 13175.
Thus, Executive Order 13175 does not apply to this rule.

IX. Congressional Review Act

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 final rule in the Federal Register. This final
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 27, 2004.
Lois Rossi,
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), 346a and 371.

? 2. Section 180.448 is amended by adding text to paragraph (b) to read
as follows:

Sec. 180.448 Hexythiazox; tolerances for residues.

* * * * *
(b) Section 18 emergency exemptions. Time-limited tolerances are
established for the combined residues of the insecticide hexythiazox
and its metabolites containing the (4-chlorophenyl)-4-methyl-2-oxo-3-
thiazolidine moiety in connection with use of the pesticide under
section 18 emergency exemptions granted by EPA. These tolerances will
expire and are revoked on the dates specified in the following table.

------------------------------------------------------------------------
Expiration/
Commodity Parts per million revocation date
------------------------------------------------------------------------
Corn, field, grain................ 0.05 ppm 12/31/07
Corn, field, forage............... 2.0 ppm 12/31/07
Corn, field, stover............... 2.0 ppm 12/31/07
------------------------------------------------------------------------

[[Page 65081]]

* * * * *
[FR Doc. 04-24926 Filed 11-9-04; 8:45 am]
BILLING CODE 6560-50-S

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Hexythiazox; Pesticide Tolerances for Emergency Exemptions

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