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d-Phenothrin; Pesticide Tolerances

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PDF Version (7 pp, 135K, About PDF)

[Federal Register: July 8, 2009 (Volume 74, Number 129)]
[Rules and Regulations]
[Page 32437-32443]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08jy09-16]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[EPA-HQ-OPP-2008-0140; FRL-8417-4]

d-Phenothrin; Pesticide Tolerances

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

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SUMMARY: This regulation establishes tolerances for residues of the
insecticide d-phenothrin [(3-phenoxyphenyl)methyl] 2,2-Dimethyl-3-(2-
methyl-1-propenyl)cyclopropanecarboxylate in or on all food/feed crops
at 0.01 parts per million (ppm) following wide-area mosquito adulticide
applications. McLaughlin Gormley King Company requested these
tolerances under the Federal Food, Drug and Cosmetic Act (FFDCA).

DATES: This regulation is effective July 8, 2009. Objections and
requests for hearings must be received on or before September 8, 2009,
and must be filed in accordance with the instructions provided in 40
CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).

ADDRESSES: EPA has established a docket for this action under docket
identification (ID) number EPA-HQ-OPP-2008-0140. All documents in the
docket are listed in the docket index available at http://
www.regulations.gov. Although listed in the index, some information is
not publicly available, e.g., Confidential Business Information (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 in the electronic
docket at http://www.regulations.gov, or, if only available in hard
copy, at the OPP Regulatory Public Docket in Room S-4400, One Potomac
Yard (South Building), 2777 S. Crystal Dr., Arlington, VA 22202-4501.
The Docket Facility is open from 8:30 a.m. to 4 p.m., Monday through
Friday, excluding legal holidays. The Docket Facility telephone number
is (703) 305-5805.

FOR FURTHER INFORMATION CONTACT: Carmen Rodia, Registration Division
(7505P), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Avenue, NW., Washington, DC 20460-0001; telephone
number: (703) 306-0327; fax number: (703) 308-0029; e-mail address:
rodia.carmen@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,
those engaged in the following activities:
    • Crop production (NAICS code 111).
    • Animal production (NAICS code 112).

[[Page 32438]]

    • Food manufacturing (NAICS code 311).
    • Pesticide manufacturing (NAICS code 32532).
    This listing is not intended to be exhaustive, but rather to
provide 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?

    In addition to accessing electronically available documents at
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. You may also access
a frequently updated electronic version of EPA's tolerance regulations
at 40 CFR part 180 through the Government Printing Office's e-CFR cite
at http://www.gpoaccess.gov/ecfr.

C. Can I File an Objection or Hearing Request?

    Under section 408(g) of FFDCA, 21 U.S.C. 346a, any person may file
an objection to any aspect of this regulation and may also request a
hearing on those objections. You must file your objection or request a
hearing on this regulation in accordance with the instructions provided
in 40 CFR part 178. To ensure proper receipt by EPA, you must identify
docket ID number EPA-HQ-OPP-2008-0140 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 as required by 40 CFR part 178
on or before September 8, 2009.
    In addition to filing an objection or hearing request with the
Hearing Clerk as described in 40 CFR part 178, please submit a copy of
the filing that does not contain any CBI for inclusion in the public
docket that is described in ADDRESSES. Information not marked
confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA
without prior notice. Submit this copy, identified by docket ID number
EPA-HQ-OPP-2008-0140, by one of the following methods:
    • Federal eRulemaking Portal: http://www.regulations.gov.
Follow the on-line instructions for submitting comments.
    • Mail: Office of Pesticide Programs (OPP) Regulatory Public
Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania
Avenue, NW., Washington, DC 20460-0001.
    • Delivery: OPP Regulatory Public Docket (7502P),
Environmental Protection Agency, Room S-4400, One Potomac Yard (South
Building), 2777 S. Crystal Dr., Arlington, VA 22202-4501. Deliveries
are only accepted during the Docket Facility's normal hours of
operation (8:30 a.m. to 4 p.m., Monday through Friday, excluding legal
holidays). Special arrangements should be made for deliveries of boxed
information. The Docket Facility telephone number is (703) 305-5805.

II. Petition for Tolerance

    In the Federal Register of September 28, 2007 (72 FR 55204) (FRL-8147-1) 
(EPA-HQ-OPP-2007-0880), EPA issued a notice pursuant to section
408(d)(3) of FFDCA, 21 U.S.C. 346a(d)(3), announcing the filing of a
pesticide petition (PP 7F7251) by McLaughlin Gormley King Company, 8810
Tenth Avenue, North, Minneapolis, MN 55427-4319.
    The petition requested that 40 CFR part 180 be amended by
establishing permanent tolerances for residues of the insecticide d-
phenothrin, [(3-phenoxyphenyl)methyl] 2,2-Dimethyl-3-(2-methyl-1-
propenyl)cyclopropanecarboxylate), in or on all food/feed crops at 0.01
ppm following wide-area mosquito adulticide applications. That notice
referenced a summary of the petition prepared by McLaughlin Gormley
King Company, the registrant, which is available to the public in the
docket, http://www.regulations.gov. There were no comments received in
response to the notice of filing.

III. Aggregate Risk Assessment and Determination of Safety

    Section 408(b)(2)(A)(i) of 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 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 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....''
    Consistent with section 408(b)(2)(D) of FFDCA, and the factors
specified in section 408(b)(2)(D) of 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 and to
make a determination on aggregate exposure for the petitioned-for
tolerances for residues of the insecticide d-phenothrin in or on all
food/feed crops at 0.01 ppm following wide-area mosquito adulticide
treatments. EPA's assessment of exposures and risks associated with
establishing tolerances follows.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its
validity, completeness and reliability as well as the relationship of
the results of the studies to human risk. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and children.
    d-Phenothrin has low acute toxicity via the oral, dermal and
inhalation routes of exposure, is only a mild eye irritant, is non-
irritating to the dermis and tests negative for skin sensitization. The
effects on the liver are the most systemically sensitive endpoint
following repeated oral exposure based on acceptable subchronic and
chronic toxicity studies in rodents and dogs, specifically, increased
liver weight, hepatocellular vacuolization and hypertrophy and, at
higher doses, increased liver serum enzymes. Based on a 90-day
inhalation study in rats, the most sensitive effects from repeated
inhalation exposure are portal of entry effects (histopathological
changes in the nasal turbinates in both sexes). This inhalation study
also indicated histological effects on the liver, thyroid and adrenal
which are of borderline toxicological significance alone, but which are
supported in part by the increased organ weights and histological
findings of similar occurrence in some oral studies. d-Phenothrin was
not associated with any systemic toxicity up to the limit dose of 1,000
mg/kg/day in a 3-week dermal toxicity study in rats.
    Currently, d-phenothrin is lacking acceptable neurotoxicity studies
and these studies are considered data gaps. The only available, but
unacceptable/non-guideline, neurotoxicity study in

[[Page 32439]]

rats indicated piloerection in animals administered at 5,000 mg/kg for
5 consecutive days; however, the rabbit developmental study provides
evidence of neurotoxicity. Indications of neurotoxicity from the rabbit
developmental study include presence of spina bifida at the mid-dose of
100 mg/kg/day, microphthalmia at 300 mg/kg/day and hydrocephaly at the
high-dose of 500 mg/kg/day. While these neurodevelopmental effects were
seen in only a single fetus each, the observations of spina bifida and
microphthalmia can be considered significant because they are uncommon
in untreated rabbits, yet they occurred together in the d-phenothrin
rabbit development study.
    As noted, developmental effects were observed in the rabbit
developmental study. Minimal adverse effects were observed at the
highest dose treated in the rat developmental study. In two acceptable
rat reproduction studies, both systemic and reproductive/offspring
toxicity occurred at the same doses with similar effects for offspring
and dams in each study (organ weight changes in the 1986 study and
decreased body weight gain in the 1995 study).
    Endocrine-related effects were observed in tests which indicated
potential estrogen, androgen and/or thyroid-mediated toxicity. d-
Phenothrin produced adrenal cortex vacuolation in the 1-year dog
feeding study and 90-day inhalation toxicity study in rats. In
addition, the 90-day inhalation toxicity study also resulted in
follicular thyroid cell enlargement. Hepatocellular enlargement was
produced in the 26-week dog feeding study, the 1-year dog feeding study
and the 90-day inhalation study, but was not always associated with
thyroid toxicity in these studies at the doses tested. The endpoints
selected for chronic dietary, incidental oral and inhalation exposure
are protective of endocrine-related effects.
    d-Phenothrin has been classified as ``Not Likely to be Carcinogenic
to Humans.'' Rat liver tumors, namely hepatocellular carcinomas,
occurred only at excessively toxic doses (limit dose) and were;
therefore, discounted and mouse liver hepatocellular adenomas, which
are common, did not achieve statistical significance (p <0.01). In
addition, an acceptable battery of mutagenicity studies was negative
for mutagenic potential.
    More detailed information on the studies received and the nature of
the adverse effects caused by d-phenothrin as well as the no-observed-
adverse-effect-level (NOAEL) and the lowest-observed-adverse-effect-
level (LOAEL) from the toxicity studies can be found in the document
entitled, ``d-Phenothrin (Sumithrin[reg]) Risk Assessment for
Reregistration Eligibility Decision (RED) and Associated Section 3
Registration Action,'' dated July 2, 2008, by going to 
http://www.regulations.gov. The referenced document is available in the
docket established by this action, which is described under ADDRESSES, and is
identified as EPA-HQ-OPP-2008-0140-0024 in that docket. Locate and
click on the hyperlink for docket ID number EPA-HQ-OPP-2008-0140.
Double-click on the document to view the referenced information on
pages 50-54 of 66.

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no
appreciable risk, a toxicological point of departure (POD) is
identified as the basis for derivation of reference values for risk
assessment. The POD may be defined as the NOAEL in the toxicology study
identified as appropriate for use in risk assessment. However, if a
NOAEL cannot be determined, the LOAEL or a Benchmark Dose (BMD)
approach is sometimes used for risk assessment. Uncertainty/safety
factors (UFs) are used in conjunction with the POD to take into account
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. Safety is assessed for
acute and chronic dietary risks by comparing aggregate food and water
exposure to the pesticide to the acute population adjusted dose (aPAD)
and chronic population adjusted dose (cPAD). The aPAD and cPAD are
calculated by dividing the POD by all applicable UFs. Aggregate short-
term, intermediate-term and chronic-term risks are evaluated by
comparing food, water and residential exposure to the POD to ensure
that the margin of exposure (MOE) called for by the product of all
applicable UFs is not exceeded. This latter value is referred to as the
Level of Concern (LOC).
    For non-threshold risks, the Agency assumes that any amount of
exposure will lead to some degree of risk. Thus, the Agency estimates
risk in terms of the probability of an occurrence of the adverse effect
greater than that expected in a lifetime. For more information on the
general principles EPA uses in risk characterization and a complete
description of the risk assessment process, see http://www.epa.gov/
pesticides/factsheets/riskassess.htm.
    A summary of the toxicological endpoints for d-phenothrin used for
human risk assessment can be found in the document entitled, ``d-
Phenothrin (Sumithrin[reg]) Risk Assessment for Reregistration
Eligibility Decision (RED) and Associated Section 3 Registration
Action,'' dated July 2, 2008, by going to http://www.regulations.gov.
The referenced document is available in the docket established by this
action, which is described under ADDRESSES, and is identified as EPA-
HQ-OPP-2008-0140-0024 in that docket. Locate and click on the hyperlink
for docket ID number EPA-HQ-OPP-2008-0140. Double-click on the document
to view the referenced information on pages 23-24 of 66.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary
exposure to d-phenothrin, EPA considered exposure under the petitioned-
for tolerances and assessed dietary exposures from d-phenothrin in food
as follows:
    i. Acute exposure. Quantitative acute dietary exposure and 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. In estimating acute dietary
exposure, EPA conducted a screening level acute dietary and drinking
water exposure assessment for the proposed new food use of d-phenothrin
for all commodities and incorporated the Agency's estimated surface
water peak concentration of 1 part per billion (ppb). An acute dietary
exposure analysis was performed for the population subgroup females 13-
49 years old only as no acute endpoint was identified for the remaining
population subgroups. The acute dietary assessment assumed tolerance-
level residues in plant and livestock commodities and 100 pecent crop
treated (PCT).
    ii. Chronic exposure. In estimating chronic dietary exposure, EPA
conducted a screening level chronic dietary and drinking water exposure
assessment for the proposed new food use of d-phenothrin and
incorporated the Agency's chronic or estimated surface water
concentration of 0.0407 ppb. The assessment assumed tolerance-level
residues in plant and livestock commodities and 100 PCT.
    iii. Cancer. As explained in Unit III.A., d-phenothrin is
considered to be ``Not Likely to be Carcinogenic to Humans.'' As a
result, an exposure assessment to evaluate cancer risk is not needed
for d-phenothrin.
    iv. Anticipated residue and PCT information. EPA did not use
anticipated residue information in the

[[Page 32440]]

dietary exposure assessment for d-phenothrin.
    2. Dietary exposure from drinking water. The Agency used screening
level water exposure models in the dietary exposure analysis and risk
assessment for d-phenothrin in drinking water. These simulation models
take into account data on the physical, chemical and fate/transport
characteristics of d-phenothrin. Further information regarding EPA
drinking water models used in pesticide exposure assessment can be
found at http://www.epa.gov/oppefed1/models/water/index.htm.
    Based on the Pesticide Root Zone Model/Exposure Analysis Modeling
System (PRZM/EXAMS) and Screening Concentration in Ground Water (SCI-
GROW) models, the estimated drinking water concentrations (EDWCs) of d-
phenothrin for acute exposures are estimated to be 0.1002 ppb for
surface water and 0.00600 ppb for ground water. Chronic exposures for
non-cancer assessments are estimated to be 0.0407 ppb for surface water
and 0.00600 ppb for ground water. Chronic exposures for cancer
assessments are estimated to be 0.0369 ppb for surface water and
0.00600 ppb for ground water.
    Modeled estimates of drinking water concentrations were directly
entered into the dietary exposure model. For acute dietary risk
assessment, the estimated surface water peak concentration value of 1
ppb was used to assess the contribution to drinking water. For chronic
dietary risk assessment, the chronic or estimated surface water
concentration value of 0.0407 ppb was used to assess the contribution
to drinking 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). Based on a review of
active labels and proposed new uses, 12 residential exposure scenarios
have been assessed for d-phenothrin. Inhalation and incidental
ingestion exposure assessments have been conducted for the residential
scenarios. Short-term and intermediate-term exposures are expected and
assessed for residential handler and post-application exposure
scenarios based on use and expected exposure patterns.
    Risk assessments were conducted for residential exposure pathways
based on registered uses. Residential post-application exposure and
risk to d-phenothrin was assessed using both deterministic and
probabilistic modeling approaches.
    The residential exposure assessment includes 2 handler and 10 post-
application residential exposure scenarios. The term ``handler''
applies to individuals who mix, load and apply the pesticide product.
The term ``post-application'' describes individuals who are exposed to
pesticides after entering areas previously treated with pesticides. d-
Phenothrin products for outdoor residential use are almost exclusively
available as aerosol sprays. There are a small number of outdoor fogger
products containing d-phenothrin (at least one); however, due to the
absence of scenario-specific exposure data for outdoor foggers, the
fact that there are very few fogger products for residential outdoor
use and the fact that assessment of aerosol sprays and mosquito ultra
low volume (ULV) applications are likely to address risks from foggers,
residential use of outdoor foggers was not assessed separately for this
analysis.
    EPA assessed residential exposure using the following assumptions:
Primary assumptions for assessing post-application exposure to use of
foggers and aerosols in indoor residential settings were based on data
provided by the Non-Dietary Exposure Task Force (NDETF). The NDETF was
formed in 1996 by members of the Pyrethrin Joint Venture and Piperonyl
Butoxide Task Force II to respond to reregistration needs and to
produce scientifically sound data on non-dietary exposures to
pyrethrins, the pyrethroids, piperonyl butoxide and MGK[reg] 264
insecticide synergist.
    EPA used the AGricultural DISPersal model (AGDISP), version
8.15.0.4, to calculate airborne concentrations of d-phenothrin from
aerial ULV mosquito abatement spray applications. ULV sprayers disperse
very fine aerosol droplets that stay aloft and kill flying mosquitoes
on contact. ULV applications involve small quantities of the
insecticide formulation in relation to the size of the area treated,
typically less than 3 ounces per acre. AGDISP provides estimates of the
1-hour average concentration and the downwind deposition of spray
material released from the aircraft equipment and predicts the motion
of spray material released, including the mean position of the material
and the position variance about the mean as a result of turbulent
fluctuations, providing a prediction of spray drift.
    For the AGDISP modeling for d-phenothrin, label recommendations
were followed, but conservative assumptions were made. The resultant
data were used to assess inhalation exposure resulting from aerial
application of d-phenothrin as a mosquito adulticide. Deposition data
from the AGDISP model were not used to assess post-application
incidental oral exposure to d-phenothrin because residential
application of d-phenothrin products outdoors to patios and lawn areas
results in higher deposition. Therefore, post-application incidental
oral exposures were assessed using estimated deposition from homeowner
application of outdoor house and garden spray products.
    Air concentrations from truck-mounted ULV spray applications are
estimated based on the SOP for residential exposure assessment for
inhalation exposure from use of an outdoor space spray for pest
control. The approach was modified to assume that 1% of the highest
application rate for a truck-mounted ULV sprayer is available in the
breathing zone of the resident. It is assumed that the full application
rates for a truck-mounted ULV sprayer (with a 1% dilution factor) is
available in the breathing zone of the residential bystander, i.e., an
application rate expressed as lbs. a.i./ft2 is converted
into a concentration expressed in a per cubic foot (ft3) basis.
    Scenario-specific data on pyrethrins and/or permethrin from the
NDETF studies were used to determine deposition of d-phenothrin on
vinyl and carpet flooring following use of a total release indoor
fogger. Given the close structural similarity of pyrethrins, permethrin
and d-phenothrin and the similarity of use patterns for these
chemicals, EPA believes that the NDETF pyrethrins and/or permethrin
data provide appropriate surrogate data for d-phenothrin. Permethrin
data were used preferentially for this assessment, if available, since
permethrin and d-phenothrin are both synthetic pyrethroids.
    Inhalation following application of an indoor total release fogger
was not modeled separately because the aerosol spray application
scenario is likely to provide a more conservative exposure estimate
and; therefore, be protective of exposures following use of a total
release fogger. While application rates for total release foggers and
aerosol sprays are comparable, labels for use of total release foggers
require that the room be closed and vacated during release of the
fogger and that the room be opened and thoroughly ventilated for a
period of time (e.g. 30 minutes, 1 hour) prior to re-entry.
    4. Cumulative effects from substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when
considering whether to establish, modify or revoke a tolerance, the
Agency consider

[[Page 32441]]

``available information'' concerning the cumulative effects of a
particular pesticide's residues and ``other substances that have a
common mechanism of toxicity.''
    d-Phenothrin is a member of the pyrethroid class of pesticides.
Although all pyrethroids alter nerve function by modifying the normal
biochemistry and physiology of nerve membrane sodium channels, EPA is
not currently following a cumulative risk approach based on a common
mechanism of toxicity for the pyrethroids. Although all pyrethroids
interact with sodium channels, there are multiple types of sodium
channels and it is currently unknown whether the pyrethroids have
similar effects on all channels and there is also no clear
understanding of effects on key downstream neuronal function e.g.,
nerve excitability, and how these key events interact to produce their
compound-specific patterns of neurotoxicity. There is ongoing research
by the Agency's Office of Research and Development and pyrethroid
registrants to evaluate the differential biochemical and physiological
actions of pyrethroids in mammals. When available, EPA will consider
this research and make a determination of common mechanism as a basis
for assessing cumulative risk. 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 EPA's website at
http://www.epa.gov/pesticides/cumulative.

D. Safety Factor for Infants and Children

    1. In general. Section 408(b)(2)(c) of FFDCA provides that EPA
shall apply an additional tenfold (10x) 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 database on toxicity
and exposure unless EPA determines based on reliable data that a
different margin of safety will be safe for infants and children. This
additional margin of safety is commonly referred to as the FQPA safety
factor (SF). In applying this provision, EPA either retains the default
value of 10x, or uses a different additional safety factor when
reliable data available to EPA support the choice of a different factor.
    2. Prenatal and postnatal sensitivity. d-Phenothrin demonstrated
qualitative and quantitative susceptibility in an acceptable rabbit
developmental study. Specifically, developmental toxicity (spina
bifida) occurred at a lower LOAEL (100 mg/kg/day) than the maternal
LOAEL (300 mg/kg/day) for decreased body weight gain and food
consumption. In rats, d-phenothrin was developmentally toxic only at a
dose of 3,000 mg/kg/day. The NOAELs and LOAELs for maternal animals and
fetuses were the same in this study. In the 1986 and 1995 rat
reproduction studies, the NOAELs/LOAELs for both maternal and
offspring/reproductive findings occurred at the same dose levels (both
studies) and the types of offspring effects (organ weight changes
(1986) and decreased mean pup weights (1995)) were also present in the
respective maternal animals from the two studies.
    3. Conclusion. The risk assessment and FFDCA safety finding for d-
phenothrin are based on a well characterized but incomplete toxicity
database. With the retention of the full FQPA SF of 10x, the toxicity
database is considered adequate to evaluate the risks to infants and
children based on the following findings:
    i. The toxicity database for d-phenothrin is incomplete for a full
hazard assessment. The toxicity database for d-phenothrin lacks
acceptable acute, subchronic and developmental neurotoxicity studies
and an immunotoxicity study. There are no indications in the available
studies that organs associated with immune function, such as the thymus
and spleen, are affected by d-phenothrin. An immunotoxicity study is
required, as a new data requirement under the 40 CFR part 158 data
requirements for registration of a pesticide (food and non-food uses).
    ii. The only available neurotoxicity study in rats is an
unacceptable/non-guideline study which demonstrated clinical signs of
piloerection but no axonal damage. The rabbit developmental study
provides evidence of neurotoxicity. Spina bifida at the mid-dose and
treatment-related presence of hydrocephaly, another serious
neurodevelopmental effect, was seen at the highest dose tested in the
rabbit developmental study. Generally, other specific neurotoxic
clinical signs were absent in other acute, subchronic and chronic d-
phenothrin studies in rats and dogs; however, d-phenothrin does not
display the full spectrum of Type 1 clinical signs in rats and dogs up
to the limit dose.
    iii. There is qualitative and quantitative evidence of increased
susceptibility for d-phenothrin in the rabbit developmental study in
the form of spina bifida at doses lower than those causing maternal
toxicity. There was no evidence of increased susceptibility in the 2-
generation reproduction study in rats. There is low concern for
quantitative and qualitative susceptibility observed in the rabbit
developmental study because the NOAELs/LOAELs in this study are well
characterized and are used to establish the acute Reference Dose
(aRfD). The NOAEL (7.1 mg/kg/day) selected for the chronic Reference
Dose (cRfD) is lower (14x) than the dose at which developmental effects
were observed.
    iv. There are no residual uncertainties identified in the exposure
databases. The dietary food exposure assessment utilizes proposed
tolerance-level or higher residues and assumes 100 PCT for all
commodities. Use of screening level dietary assessments ensures that
acute and chronic dietary risks will not be underestimated. The Tier 1
drinking water assessment uses model parameters designed to provide
conservative, health protective estimates of water concentrations.
Post-application exposure to children was assessed using maximum
application rates and established exposure assumptions. Based on
standard assumptions, most residential scenarios were not of concern
(MOEs > 1,000). For those assessments with MOEs < 1,000, a refined
probabilistic analysis was carried out and all scenarios passed (all
MOEs > 1,000) at the 99th percentile level.
    The FQPA 10x SF is to be retained primarily due to the absence of
needed acute, subchronic and developmental neurotoxicity studies in
conjunction with a finding of increased sensitivity for a neurological
effect in the rabbit developmental study. EPA finds that an additional
10x SF will protect the safety of infants and children because the
neurotoxic effects were generally not seen in the d-phenothrin toxicity
database and when those effects were seen it was at comparatively high doses.

E. Aggregate Risks and Determination of Safety

    EPA determines whether acute and chronic pesticide exposures are
safe by comparing aggregate exposure estimates to the aPAD and cPAD.
The aPAD and cPAD represent the highest safe exposures, taking into
account all appropriate SFs. EPA calculates the aPAD and cPAD by
dividing the POD by all applicable UFs. For linear cancer risks, EPA
calculates the probability of additional cancer cases given the
estimated aggregate exposure. Short-term, intermediate-term and
chronic-term risks are evaluated by comparing the estimated aggregate
food, water and residential exposure to the POD to ensure that the MOE
called for by the product of all applicable UFs is not exceeded.

[[Page 32442]]

    The aggregate risk assessment integrates the assessments conducted
for dietary/drinking water and residential exposure. Since there is
potential for concurrent exposure via the food, water and residential
pathways, all routes of d-phenothrin exposure have been considered.
    1. Acute risk. An acute aggregate risk assessment takes into
account exposure estimates from acute dietary consumption of food and
drinking water. Acute dietary exposure analysis was performed for the
population subgroup females 13-49 years old only. No adverse effect
resulting from a single-oral exposure was identified and no acute
dietary endpoint was selected for the general population or other
population subgroups. Using the exposure assumptions discussed in this
unit for acute exposure, the acute dietary exposure from food and water
to d-phenothrin will occupy 1.3% of the aPAD for females 13-49 years
old, the population group receiving the greatest exposure.
    2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that chronic exposure to
d-phenothrin from food and water will utilize 13% of the cPAD for
children 1-2 years old, the population group receiving the greatest
exposure. Based on the explanation in Unit III.C.3., regarding
residential use patterns, chronic residential exposure to residues of
d-phenothrin is not expected.
    3. Short-term risk. The short- and itermediate-term aggregate risk
is the estimated risk associated with combined risks from average food
exposures, average drinking water exposures, incidental oral exposures
and inhalation exposures. Exposure from oral and inhalation exposure
pathways is not aggregated for d-phenothrin because the toxicity
endpoints for these exposure routes are not based on common specific
target organ toxicity effects. Aggregate risk from exposure to d-
phenothrin residues from food, drinking water and incidental oral
exposures do not present risks of concern.
    4. 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 or to infants and children from aggregate
exposure to d-phenothrin residues.
    For more detailed information on non-dietary (residential)
exposure, including the use of the AGDISP and CARES models and the
NDETF data as part of assessing residential exposure to d-phenothrin,
please refer to the document entitled, ``d-Phenothrin (Sumithrin[reg])
Risk Assessment for Reregistration Eligibility Decision (RED) and
Associated Section 3 Registration Action,'' dated July 2, 2008, by
going to http://www.regulations.gov. The referenced document is
available in the docket established by this action, which is described
under ADDRESSES, and is identified as EPA-HQ-OPP-2008-0140-0024 in that
docket. Locate and click on the hyperlink for docket ID number EPA-HQ-
OPP-2008-0140. Double-click on the document to view the referenced
information on pages 31-42 of 66.
    In addition, for more detailed information on the refinements
incorporated as part of the probabilistic assessment of d-phenothrin,
please refer to the document entitled, ``d-Phenothrin (Sumithrin[reg]):
Addendum to Residential Exposure Assessment,'' dated August 19, 2008,
by going to http://www.regulations.gov. The referenced document is
available in the docket established by this action, which is described
under ADDRESSES, and is identified as EPA-HQ-OPP-2008-0140-0029 in that
docket. Locate and click on the hyperlink for docket ID number EPA-HQ-
OPP-2008-0140. Double-click on the document to view the referenced information.

IV. Other Considerations

A. Analytical Enforcement Methodology

    No multiresidue monitoring protocol data were submitted by the
registrant for d-phenothrin. No analytical method was recommended by
the registrant for enforcement. However, the United States Food and
Drug Administration (FDA) has tested d-phenothrin through their
multiresidue protocols. d-Phenothrin is completely recovered through
protocol 302, but only 60% remains after florisil cleanup, which is
rarely used any more. No additional data are needed from the registrant.
    Adequate enforcement methodology is available to enforce the
tolerance expression. FDA's Pacific Regional Laboratory Northwest has
developed a gas chromatography/mass spectrometry detection (GC/MSD)
method that recovers d-phenothrin. 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 currently no established CODEX, Canadian or Mexican
maximum residue limits (MRLs) for residues of the insecticide d-
phenothrin in or on all food/feed crops following wide-area mosquito
adulticide applications.

V. Conclusion

    Therefore, tolerances are established for residues of the
insecticide d-phenothrin ([(3-phenoxyphenyl)methyl] 2,2-Dimethyl-3-(2-
methyl-1-propenyl)cyclopropanecarboxylate).

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances under section 408(d) of
FFDCA in response to a petition submitted to the Agency. The Office of
Management and Budget (OMB) has exempted these types of actions from
review under Executive Order 12866, entitled Regulatory Planning and
Review (58 FR 51735, October 4, 1993). Because this final rule has been
exempted from review under Executive Order 12866, this final rule is
not subject to Executive Order 13211, entitled Actions Concerning
Regulations That Significantly Affect Energy Supply, Distribution, or
Use (66 FR 28355, May 22, 2001) or Executive Order 13045, entitled
Protection of Children from Environmental Health Risks and Safety Risks
(62 FR 19885, April 23, 1997). 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., 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).
    Since tolerances and exemptions that are established on the basis
of a petition under section 408(d) of FFDCA, such as the tolerance in
this final rule, do not require the issuance of a proposed rule, the
requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et
seq.) do not apply.
    This final rule directly regulates growers, food processors, food
handlers and food retailers, not States or tribes, nor does this action
alter the relationships or distribution of power and responsibilities
established by Congress in the preemption provisions of section
408(n)(4) of FFDCA. As such, the Agency has determined that this action
will not have a substantial direct effect on States or tribal
governments, on the relationship between the national government and
the States or tribal governments or on the distribution of power and
responsibilities among the various levels of government or between the
Federal Government and Indian tribes. Thus, the Agency has determined

[[Page 32443]]

that Executive Order 13132, entitled Federalism (64 FR 43255, August
10, 1999) and Executive Order 13175, entitled Consultation and
Coordination with Indian Tribal Governments (59 FR 22951, November 9,
2000) do not apply to this final rule. In addition, this final rule
does not 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).
    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).

VII. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report 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: June 19, 2009.
Steven Bradbury,
Acting Director, Office of Pesticide Programs.

• Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

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

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

• 2. Section 180.647 is added to read as follows:

Sec.  180.647  d-Phenothrin; tolerances for residues.

    (a) General. A tolerance of 0.01 parts per million is established
for residues of the insecticide d-phenothrin in or on all food/feed
crops following wide-area mosquito adulticide applications.
    (b) Section 18 emergency exemptions. [Reserved]
    (c) Tolerances with regional registrations. [Reserved]
    (d) Indirect or inadvertent residues. [Reserved]

[FR Doc. E9-15937 Filed 7-7-09; 8:45 am]
BILLING CODE 6560-50-S

 
 


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