Emamectin Benzoate; Pesticide Tolerances for Emergency Exemptions

Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 [Federal Register: May 16, 1997 (Volume 62, Number 95)]
[Rules and Regulations]
[Page 26941-26946]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16my97-9]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300490; FRL-5718-1]
RIN 2070-AB78

Emamectin Benzoate; Pesticide Tolerances for Emergency Exemptions

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

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SUMMARY: This regulation establishes a time-limited tolerance for
residues of the insecticide emamectin benzoate: 4''-epi-methylamino-
4''-deoxyavermectin B1 benzoate in or on the raw agricultural
commodities head and Napa (chinese) cabbage in connection with EPA's
granting an emergency exemption under section 18 of the Federal
Insecticide, Fungicide, and Rodenticide Act authorizing use of the
pesticide on head and Napa cabbage in Hawaii. The tolerance will expire
and is revoked on December 31, 1998.

DATES: This regulation becomes effective May 16, 1997. Objections and
requests for hearings must be received by EPA on or before July 15, 1997.

ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [OPP-300490], 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-300490], must be submitted to: Public Information
and Records Integrity Branch, Information Resources and Services
Division (7506C), 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. 1132, 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 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-300490]. 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: Olga Odiott, Registration
Division (7505W), Office of Pesticide Programs, Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460. Office
location, telephone number, and e-mail: Sixth Floor, Crystal Station
#1, 2800 Jefferson Davis Highway, Arlington, VA. (703) 308-6418, e-
mail: odiott.olga@epamail.epa.gov.

SUPPLEMENTARY INFORMATION: The regulations governing section 18 require
that the Agency publish a notice of receipt in the Federal Register and
solicit public comment on an application for a specific exemption
proposing the use of an unregistered chemical [40 CFR 166.24].
Emamectin benzoate is an active ingredient not currently found in any
registered product. Accordingly, a notice of receipt of this request
was published in the Federal Register on April 11, 1997. One comment
was received regarding the requirement for a groundwater monitoring
study. EPA is not requiring such study under section 18. Based on the
available environmental fate data, the Agency has determined that the
use proposed by this emergency exemption will not cause unreasonable
adverse effects on the environment. EPA, on its own initiative,
pursuant to section 408(e) and (l)(6) of the Federal Food, Drug, and
Cosmetic Act (FFDCA), 21 U.S.C. 346a(e) and (l)(6), is establishing a
tolerance for residues of the insecticide 4''-epi-methylamino-4''-
deoxyavermectin B1 benzoate, also referred to in this document as
emamectin benzoate, in or on head and Napa cabbage at 0.025 part per
million (ppm). This tolerance will expire and be revoked by EPA on
December 31, 1998. After December 31, 1998, EPA will publish a document
in the Federal Register to remove the revoked tolerance from the Code
of Federal Regulations.

I. Background and Statutory Authority

    The Food Quality Protection Act of 1996 (FQPA) (Pub. L. 104-170)
was signed into law August 3, 1996. FQPA amends both the Federal Food,
Drug and Cosmetic Act (FFDCA), 21 U.S.C. 301 et seq., and the Federal
Insecticide, Fungicide, and Rodenticide Act (FIFRA), 7 U.S.C. 136 et
seq. Among other things, FQPA amends FFDCA to bring all EPA pesticide
tolerance-setting activities under section 408 with a new safety
standard and new procedures. These activities are described below and
discussed in greater detail in the final rule establishing the time-
limited tolerance associated with the emergency exemption for use of
propiconazole on sorghum (61 FR 58135, November 13, 1996) (FRL-5572-9).
    New section 408(b)(2)(A)(i) of the FFDCA allows EPA to establish a
tolerance (the legal limit for a pesticide chemical residue in or on a
food) only if EPA determines that the tolerance is ``safe.'' Section
408(b)(2)(A)(ii) defines ``safe'' to mean that ``there is a reasonable
certainty that no harm will result from aggregate exposure to the
pesticide chemical residue, including all anticipated dietary exposures
and all other exposures for which there is reliable information.'' This
includes exposure through drinking water and in residential settings,
but does not include occupational exposure. Section 408(b)(2)(C)
requires EPA to give special consideration to exposure of infants and
children to the pesticide chemical residue in establishing a tolerance
and to ``ensure that there is a reasonable certainty that no harm will
result to infants and children from aggregate exposure to the pesticide
chemical residue....''
    Section 18 of 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 FQPA. EPA has established regulations governing such
emergency exemptions in 40 CFR part 166. 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

[[Page 26942]]

by EPA under section 18 of FIFRA. Such tolerances can be established
without providing notice or period for public comment.
    Because decisions on section 18-related tolerances must proceed
before EPA reaches closure on several policy issues relating to
interpretation and implementation of the FQPA, EPA does not intend for
its actions on such tolerances to set binding precedents for the
application of section 408 and the new safety standard to other
tolerances and exemptions.

II. Emergency Exemption for Emamectin Benzoate on Head and Napa
Cabbage and FFDCA Tolerances

    The Hawaii Department of Agriculture has requested a specific
exemption for the use of emamectin benzoate on head and Napa cabbage to
control the diamondback moth (Plutella xylostella). The Applicant
states that although there are numerous insecticides registered for use
against the diamondback moth (DBM) on cabbage in Hawaii, these
pesticides do not provide effective control. DMB has become resistant
to most of these insecticides and label restrictions on others render
their control inadequate for this pest. Growers using these products
have experienced significant yield reductions due to feeding damage by
DBM larvae. Bacillus thuringiensis (Bt) based insecticides were once
very effective, but in 1990 scientists at the University of Hawaii
documented DBM resistance to first generation Bt products; more
recently these same scientists have documented a 20-fold resistance to
Bt toxin CryIC. Based on these trends, it is expected that the DBM will
quickly develop resistance to these second generation Bt products if
they are overused. Alternative control practices include the use of
tolerant cabbage varieties, natural enemy augmentation, and the
application of overhead irrigation. Management programs incorporating
these practices have been adopted by many cabbage growers; however the
growers continued to experience moderate to excessive yield losses due
to DBM injury. Thus, without an effective control such as emamectin
benzoate, cabbage growers in Hawaii will likely suffer severe economic
losses. EPA has authorized under FIFRA section 18 the use of emamectin
benzoate on cabbage for control of the DBM. 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 emamectin benzoate in or
on cabbage. In doing so, EPA considered the new safety standard in
FFDCA section 408(b)(2), and decided that the necessary tolerance under
FFDCA section 408(l)(6) would be consistent with the new safety
standard and with FIFRA section 18. This tolerance will permit the
marketing of head and Napa cabbage treated in accordance with the
provisions of the section 18 emergency exemption. Consistent with the
need to move quickly on the emergency exemption in order to address an
urgent non-routine situation and to ensure that the resulting food is
safe and lawful, EPA is issuing this tolerance without notice and
opportunity for public comment under section 408(e), as provided in
section 408(l)(6). Although this tolerance will expire and is revoked
on December 31, 1998, under FFDCA section 408(l)(5), residues of the
pesticide not in excess of the amounts specified in the tolerance
remaining in or on head and Napa cabbage after that date will not be
unlawful, provided the pesticide is applied during the term of, and in
accordance with all the conditions of, section 18 of FIFRA. EPA will
take action to revoke this tolerance earlier if any experience with,
scientific data on, or other relevant information on this pesticide
indicate that the residues are not safe.
    EPA has not made any decisions about whether emamectin benzoate
meets EPA's registration requirements for use on head and Napa cabbage
or whether a permanent tolerance for this use would be appropriate.
This tolerance does not serve as a basis for registration of emamectin
benzoate by a State for special local needs under FIFRA section 24(c).
Nor does this tolerance serve as the basis for any State other than
Hawaii to use this pesticide on this crop under section 18 of FIFRA
without following all provisions of section 18 as identified in 40 CFR
part 166. For additional information regarding the emergency exemption
for emamectin benzoate, contact the Agency's Registration Division at
the address provided above.

III. Risk Assessment and Statutory Findings

    EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. First, EPA determines the
toxicity of pesticides based primarily on toxicological studies using
laboratory animals. These studies address many adverse health effects,
including (but not limited to) reproductive effects, developmental
toxicity, toxicity to the nervous system, and carcinogenicity. For many
of these 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 effect level'' or
``NOEL'').
    Once a study has been evaluated and the observed effects have been
determined to be threshold effects, EPA generally divides the NOEL from
the study with the lowest NOEL 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 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 NOEL 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 NOEL will be
carried out based on the nature of the carcinogenic response and the
Agency's knowledge of its mode of action.
    In examining aggregate exposure, FFDCA section 408 requires that
EPA take into account available and reliable information concerning
exposure from

[[Page 26943]]

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. 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.

IV. 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.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its
validity, completeness, and reliability as well as the relationship of
the results of the studies to human risk. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and
children. The nature of the toxic effects caused by emamectin benzoate
are discussed below.
    1. Acute toxicity. The Agency has determined that the NOEL of 0.075
mg/kg/day from a 15-day feeding study in mice should be used to
evaluate acute dietary risk. At the lowest effect level (LEL) of 0.10
mg/kg/day, there were clinical signs of tremors and histological
evidence of degenerative effects in the sciatic nerve. This acute
dietary risk assessment evaluates neurological risks to all population
subgroups.
    2. Short- and intermediate-term dermal and inhalation toxicity. The
Agency has determined that a NOEL of 2.4 mg/kg/day from a 21-day dermal
toxicity study in rabbits should be used to assess risks from short and
intermediate-term dermal toxicity. At the LEL of 6.0 mg/kg/day, there
were axonal degenerative lesions in the sciatic nerve and spinal cord.
For the short- and intermediate-term inhalation toxicity, the Agency
has determined that a NOEL of 0.075 mg/kg/day from the 15-day feeding
study in mice [same study used in the acute dietary risk assessment]
should be used to assess risks for occupational scenarios since no
suitable inhalation toxicity study is available. At the LEL of 0.10 mg/
kg/day, there were tremors, and histological degenerative effects in
the sciatic nerve.
    3. Chronic risk. The Agency has established a provisional RfD for
emamectin benzoate at 0.000083 mg/kg/day. The provisional RfD was based
on one-year and 90-day feeding studies in dogs with a NOEL of 0.25 mg/
kg/day and an uncertainty factor of 3000 based on severe neurological
effects, the steep dose response in the dog studies, data gaps in the
chronic studies in mice and rats, and the extra-sensitivity for infants
and children which was seen in the developmental neurotoxicity study.
At the LEL of 0.50 mg/kg/day, effects in both sexes consist of axonal
degeneration in the pons; medulla, sciatic, sural, and tibial; whole
body tremors; stiffness of hind legs; spinal cord axonal degeneration;
and muscle fiber degeneration in females. At the highest dose tested,
0.75 mg/kg/day, males were sacrificed after 7 weeks, and additional
effects were mydriasis, cellular degeneration of retina, axonal
degeneration of optic nerve, decreased body weight gain and decreased
food consumption.
    The Agency has also determined that a non-dietary chronic toxicity
endpoint does not exist for emamectin benzoate and a chronic risk
assessment is not required for occupational exposures.
    4. Cancer risk. The carcinogenicity studies for emamectin benzoate
have not been fully evaluated, therefore a cancer risk assessment is
not possible at this time.

B. Exposures and Risks

    In examining aggregate exposure, FQPA directs EPA to consider
available information concerning exposures from the pesticide residue
in food and all other non-occupational exposures. The primary non-food
sources of exposure the Agency looks at include drinking water (whether
from groundwater or surface water), and exposure through pesticide use
in gardens, lawns, or buildings (residential and other indoor uses). In
evaluating food exposures, EPA takes into account varying consumption
patterns of major identifiable subgroups of consumers, including
infants and children.
    1. From food and feed uses. Emamectin benzoate is not currently
registered for food uses and no tolerances have been established. Risk
assessments were conducted by EPA to assess dietary exposures and risks
from emamectin benzoate as follows:
    i. Acute 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.
    Since emamectin benzoate is not currently registered for food uses,
the use proposed by this Section 18 is the only commodity considered in
the acute dietary risk assessment. In conducting this risk assessment,
the Agency used the tolerance value of 0.025 ppm and assumed 100% crop
treated. Thus, the acute dietary risk estimates are considered
conservative and therefore protective of any acute exposure scenario.
The acute dietary risks from this proposed Section 18 use do not exceed
the Agency's level of concern. The resulting MOEs for the different
population subgroups ranged from 150 to 540. Further refinement using
anticipated residue values and percent crop-treated data would result
in lower acute dietary risk estimates.
    ii. Chronic risk. For the chronic dietary risk assessment, the
Agency used the tolerance value of 0.025 ppm, and assumed that all
cabbage consumed in the U.S. will contain residues at the tolerance
level. Thus, in making a safety determination for this tolerance, EPA
is taking into account a conservative exposure assessment. With this
Section 18 use of emamectin benzoate on cabbage, the TMRC estimates

[[Page 26944]]

represented 0% to 4% of the RfD (all TMRCs were <0.00001 mg/kg/day).
The EPA has therefore concluded that the chronic dietary risks from the
proposed Section 18 use do not exceed our level of concern.
    2. From drinking water. No Maximum Concentration Level has been
established for residues of emamectin benzoate in drinking water. No
Health Advisory Levels for emamectin benzoate in drinking water have
been established.
    Because the Agency lacks sufficient water-related exposure data to
complete a comprehensive drinking water risk assessment for many
pesticides, EPA has commenced and nearly completed a process to
identify a reasonable yet conservative bounding figure for the
potential contribution of water related exposure to the aggregate risk
posed by a pesticide. In developing the bounding figure, EPA estimated
residue levels in water for a number of specific pesticides using
various data sources. The Agency then applied the estimated residue
levels, in conjunction with appropriate toxicological endpoints (RfD's
or acute dietary NOEL's) and assumptions about body weight and
consumption, to calculate, for each pesticide, the increment of
aggregate risk contributed by consumption of contaminated water. While
EPA has not yet pinpointed the appropriate bounding figure for exposure
from contaminated water, the ranges the Agency is continuing to examine
are all below the level that would cause emamectin benzoate to exceed
the RfD if the tolerance being considered in this document is granted.
The Agency has therefore concluded that the potential exposures
associated with emamectin benzoate in water, even at the higher levels
the Agency is considering as a conservative upper bound, would not
prevent the Agency from determining that there is a reasonable
certainty of no harm if the tolerance is granted.
    3. From non-dietary exposure. Emamectin benzoate is not currently
registered for non-food uses.

C. Cumulative Exposure to Substances with Common Mechanism of Toxicity

    Section 408(b)(2)(D)(v) requires that, when considering whether to
establish, modify, or revoke a tolerance, the Agency consider
``available information'' concerning the cumulative effects of a
particular pesticide's residues and ``other substances that have a
common mechanism of toxicity.'' The Agency believes that ``available
information'' in this context might include not only toxicity,
chemistry, and exposure data, but also scientific policies and
methodologies for understanding common mechanisms of toxicity and
conducting cumulative risk assessments. For most pesticides, although
the Agency has some information in its files that may turn out to be
helpful in eventually determining whether a pesticide shares a common
mechanism of toxicity with any other substances, EPA does not at this
time have the methodologies to resolve the complex scientific issues
concerning common mechanism of toxicity in a meaningful way. EPA has
begun a pilot process to study this issue further through the
examination of particular classes of pesticides. The Agency hopes that
the results of this pilot process will increase the Agency's scientific
understanding of this question such that EPA will be able to develop
and apply scientific principles for better determining which chemicals
have a common mechanism of toxicity and evaluating the cumulative
effects of such chemicals. The Agency anticipates, however, that even
as its understanding of the science of common mechanisms increases,
decisions on specific classes of chemicals will be heavily dependent on
chemical specific data, much of which may not be presently available.
    Although at present the Agency does not know how to apply the
information in its files concerning common mechanism issues to most
risk assessments, there are pesticides as to which the common mechanism
issues can be resolved. These pesticides include pesticides that are
toxicologically dissimilar to existing chemical substances (in which
case the Agency can conclude that it is unlikely that a pesticide
shares a common mechanism of activity with other substances) and
pesticides that produce a common toxic metabolite (in which case common
mechanism of activity will be assumed).
    EPA does not have, at this time, available data to determine
whether emamectin benzoate has a common mechanism of toxicity with
other substances or how to include this pesticide in a cumulative risk
assessment. For the purposes of this tolerance action, therefore, EPA
has not assumed that emamectin benzoate has a common mechanism of
toxicity with other substances.

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

    1. Acute risk. For the U.S. population, the calculated dietary
(food only) MOE value is 250. This MOE value does not exceed the
Agency's level of concern for acute dietary exposures. Despite the
potential for exposure to emamectin benzoate from drinking water, EPA
does not expect the aggregate acute risk (food + water) to exceed the
Agency's level of concern.
    2. Chronic risk. Using the conservative TMRC exposure assumptions
described above, EPA has concluded that exposure to emamectin benzoate
from food will utilize 1% of the RfD for the U.S. population. EPA
generally has no concern for exposures below 100% of the RfD because
the RfD represents the level at or below which daily aggregate dietary
exposure over a lifetime will not pose appreciable risks to human
health. Despite the potential for exposure to emamectin benzoate in
drinking water, EPA does not expect the aggregate exposure to exceed
100% of the RfD. EPA concludes that there is a reasonable certainty
that no harm will result from aggregate exposure to emamectin benzoate
residues.

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

    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. 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. EPA believes that reliable data support using the standard MOE
and uncertainty factor (usually 100 for combined inter- and intra-
species variability)) and not the additional tenfold margin of
exposure/uncertainty factor when EPA has a complete data base under
existing guidelines and when the severity of the effect in infants or
children or the potency or unusual toxic properties of a compound do
not raise concerns regarding the adequacy of the standard margin of
exposure/safety factor.
    In assessing the potential for additional sensitivity of infants
and children to residues of emamectin benzoate, EPA considered data
from developmental toxicity studies in rats and rabbits, developmental
neurotoxicity studies in rats, and a two-generation reproductive
toxicity study in rats. The developmental toxicity studies are designed
to evaluate adverse effects on the developing organism resulting from
maternal pesticide exposure during prenatal development. Reproduction
studies provide information relating to pre- and post-natal effects
from exposure to the

[[Page 26945]]

pesticide, information on the reproductive capability of mating
animals, and data on systemic toxicity.
    1. Developmental toxicity studies.--a. Developmental toxicity study
in rats. The maternal (systemic) NOEL was 2 mg/kg/day, based on
decreased weight gain at the lowest observed effect level (LOEL) of 4
mg/kg/day. The developmental (fetal) NOEL was 4 mg/kg/day, based on
altered growth and extra ribs at the LOEL of 8 mg/kg/day.
    b. Developmental neurotoxicity study in rats. The maternal
(systemic) NOEL was 2.5 mg/kg/day. The developmental (pup) NOEL was
0.10 mg/kg/day [lowest dose tested], based on neurotoxicity findings at
the LOEL of 0.60 mg/kg/day.
    c. Developmental study in rabbits. The maternal (systemic) NOEL was
3 mg/kg/day, based on decreased weight gain and neurotoxicity at the
LOEL of 6 mg/kg/day. The developmental (fetal) NOEL was 6 mg/kg/day
[highest dose tested].
    2. Reproductive toxicity studies.--a. Reproductive toxicity study
in rats. The parental (systemic) NOEL was 0.6 mg/kg/day, based on
neurological lesions and decreased weight gain at the LOEL of 1.8 mg/
kg/day. The developmental (pup) NOEL was 0.6 mg/kg/day, based on
neurological effects at the LEL of 1.8 mg/kg/day.
    The reproductive NOEL was 0.8 mg/kg/day, based on decreased
fecundity and fertility indices at the LEL of 1.8 mg/kg/day.
    3. Pre- and post-natal sensitivity. Based on the results of the
developmental neurotoxicity study for emamectin benzoate, the
developmental findings [neurotoxicity], which may be due to pre- or/and
post-natal extra-sensitivity, occurred in the absence of maternal
effects. These results indicate extra-sensitivity for infants and
children and an additional uncertainty factor of 3 was added to the
provisional RfD due to these results.
    Based on the reproductive toxicity study discussed above, for
emamectin benzoate there does not appear to be a special sensitivity
for post-natal effects. The NOELs and LOELs for both parental animals
and offspring occur at the same doses of 0.6 and 1.8 mg/kg/day,
respectively.
    4. Acute risk. The acute dietary (food only) MOE for infants (< 1
year) was calculated to be 150, and that for children (1-6 years) was
calculated to be 150. The acute dietary (food only) MOE for females 13+
years old (accounts for both maternal and fetal exposure) is 420. These
MOE calculations are based on the NOEL (0.075 mg/kg/day) from a 15-day
feeding study in mice. This risk assessment also assumed 100% crop-
treated with tolerance level residues on all treated crops consumed,
resulting in an over-estimate of dietary exposure. Despite the
potential for exposure to emamectin benzoate in drinking water, EPA
does not expect the aggregate acute exposure (food + water) to result
in an MOE of less than 100. The large acute dietary MOE calculated for
females 13+ years old provides assurance that there is a reasonable
certainty of no harm for both females 13+ years and the pre-natal
development of infants.
    5. Chronic risk. Using the conservative exposure assumptions
described above, EPA has concluded that the percent of the RfD that
will be utilized by dietary (food only) exposure to residues of
emamectin benzoate ranges from 0% for non-nursing infants less than one
year old, up to 1% for non-nursing infants (<1 year old), children (1-6
years old), and children (7-12 years old). Despite the potential for
exposure to emamectin benzoate in drinking water, EPA does not expect
the aggregate exposure to exceed 100% of the RfD. Therefore, taking
into account the completeness and reliability of the toxicity data and
the conservative exposure assessment, EPA concludes that there is a
reasonable certainty that no harm will result to infants and children
from aggregate exposure to emamectin benzoate residues.

V. Other Considerations

A. Metabolism in Plants and Animal

    Plant metabolism studies for emamectin benzoate on cabbage, head
lettuce, and sweet corn have been submitted to the Agency, however, the
studies have not been fully evaluated to determine the residue(s) of
concern. For the purposes of this Section 18, the regulated residues of
concern are the parent compound emamectin benzoate (including the
4''hylamino-4''-deoxyavermectin B1A and the 4''-epi-methylamino-4''-
deoxyavermectin B1B components), its delta-8,9-isomer, and the
degradation products 4''-deoxy-4''-epi-(N-formyl)-avermectin B1, 4''-
deoxy-4''-epi-(N-formyl-N-methyl)-avermectin B1, and 4''-deoxy-4''-epi-
amino avermectin B1.

B. Analytical Enforcement Methodology

    There is a practical analytical method for detecting and measuring
levels of emamectin benzoate in or on cabbage with a limit of detection
that allows monitoring of food with residues at or above the level set
in this tolerance. The method has undergone succesful independent
laboratory validation, but has not been forwarded to the EPA Analytical
Chemistry Laboratory pending EPA's determination of emamectin benzoate
regulable residues of concern.

C. Magnitude of Residues

    Regulable residues of emamectin benzoate are not expected to exceed
0.025 ppm in/on cabbage as a result of this Section 18 use. Secondary
residues are not expected in animal commodities as no feed items are
associated with this Section 18 use.

D. International Residue Limits

    No CODEX, Canadian, or Mexican maximum residue limits/tolerances
have been established for emamectin benzoate at this time.

VI. Conclusion

    Therefore, a tolerance in connection with the FIFRA section 18
emergency exemptions is established for residues of emamectin benzoate
in or on head and Napa cabbage at 0.025 ppm.

VII. Objections and Hearing Requests

    The new FFDCA section 408(g) provides essentially the same process
for persons to ``object'' to a tolerance regulation issued by EPA under
new section 408(e) and (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 July 15, 1997 file written objections to any
aspect of this regulation (including the revocation provision) and may
also request a hearing on those objections. Objections and hearing
requests must be filed with the Hearing Clerk, at the address given
above (40 CFR 178.20). A copy of the objections and/or hearing requests
filed with the Hearing Clerk should be submitted to the OPP docket for
this rulemaking. The objections submitted must specify the provisions
of the regulation deemed objectionable and the grounds for the
objections (40 CFR 178.25). Each objection must be accompanied by the
fee prescribed by 40 CFR 180.33(I). If a hearing is requested, the
objections must include a statement of the factual 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

[[Page 26946]]

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 Confidential Business Information (CBI). Information so
marked will not be disclosed except in accordance with procedures set
forth in 40 CFR part 2. A copy of the information that does not contain
CBI must be submitted for inclusion in the public record. Information
not marked confidential may be disclosed publicly by EPA without prior
notice.

VIII. Public Docket

    A record has been established for this rulemaking under docket
control number [OPP-300490]. A public version of this record, which
does not include any information claimed as CBI, is available for
inspection from 8 a.m. to 4:30 p.m., Monday through Friday, excluding
legal holidays. The public record is located in Room 1132 of the Public
Information and Records Integrity Branch, Information Resources and
Services Division (7506C), Office of Pesticide Programs, Environmental
Protection Agency, Crystal Mall #2, 1921 Jefferson Davis Highway,
Arlington, VA.
    The official record for this rulemaking, as well as the public
version, as described above, is kept in paper form. Accordingly, in the
event there are objections and hearing requests, EPA will transfer any
copies of objections and hearing requests received electronically into
printed, paper form as they are received and will place the paper
copies in the official rulemaking record. The official rulemaking
record is the paper record maintained at the address in ``ADDRESSES''
at the beginning of this document.

IX. Regulatory Assessment Requirements

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), this
action is not a ``significant regulatory action'' and, since this
action does not impose any information collection requirements as
defined by the Paperwork Reduction Act, 44 U.S.C. 3501 et seq., it is
not subject to review by the Office of Management and Budget. In
addition, this action does not impose any enforceable duty or contain
any unfunded mandate as described in the Unfunded Mandates Reform Act
of 1995 (Pub. L. 104-4), or require prior consultation with State
officials as specified by Executive Order 12875 (58 FR 58093, October
28, 1993), or special considerations as required by Executive Order
12898 (59 FR 7629, February 16, 1994).
    Because FFDCA section 408(l)(6) permits establishment of this
regulation without a notice of proposed rulemaking, the regulatory
flexibility analysis requirements of the Regulatory Flexibility Act, 5
U.S.C. 604(a), do not apply. Nonetheless, the Agency has previously
assessed whether establishing tolerances or exemptions from tolerance,
raising tolerance levels, or expanding exemptions adversely impact
small entities and concluded, as a generic matter, that there is no
adverse impact. (46 FR 24950, May 4, 1981).
    Under 5 U.S.C. 801(a)(1)(A) of the Small Business Regulatory
Enforcement Fairness Act of 1996 (Title II of Pub. L. 104-121, 110
Stat. 847), EPA submitted a report containing this rule and other
required information to the U.S. Senate, the U.S. House of
Representatives and the Comptroller General of the General Accounting
Office prior to publication of the rule in today's Federal Register.
This rule is not a ``major rule'' as defined by 5 U.S.C. 804(2).

List of Subjects in 40 CFR Part 180

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

    Dated: May 8, 1997.

James Jones,

Acting 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. 346a and 371.

    2. Section 180.505 is added to read as follows:

Sec. 180.505  Emamectin benzoate; tolerances for residues.

    (a) General. [Reserved]
    (b) Section 18 emergency exemptions. A time-limited tolerance is
established for residues of the insecticide emamectin benzoate: 4''-
epi-methylamino-4''-deoxyavermectin B1 benzoate in connection with use
of the pesticide under section 18 emergency exemptions granted by EPA.
The tolerance will expire and is revoked on the date specified in the
following table.

--------------------------------------------------------------------------
                                                   Expiration/ Revocation
Commodity                    Parts per million               Date
--------------------------------------------------------------------------
Cabbage (head and Napa)...            0.025       December 31, 1998.
--------------------------------------------------------------------------

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

[FR Doc. 97-12787 Filed 5-15-97; 8:45 am]
BILLING CODE 6560-50-F
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Emamectin Benzoate; Pesticide Tolerances for Emergency Exemptions

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