[Federal Register: April 30, 2003 (Volume 68, Number 83)]
[Rules and Regulations]
[Page 23056-23068]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30ap03-9]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-2002-0358; FRL-7304-4]
Bifenthrin; Pesticide Tolerance
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes tolerances for residues of
bifenthrin in or on almond, hulls; banana; fruit, citrus, group; herb
subgroup; pear; nut, tree, group; spinach; tomato; and food/feed
products in food/feed handling establishments. FMC Corporation and the
Interregional Research Project Number 4 (IR-4) requested these
tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA) , as
amended by the Food Quality Protection Act of 1996 (FQPA).
DATES: This regulation is effective April 30, 2003. Objections and
requests for hearings, identified by docket ID number OPP-2002-0358,
must be received on or before June 30, 2003.
ADDRESSES: Written objections and hearing requests may be submitted
electronically, by mail, or through hand delivery/courier. Follow the
detailed instructions as provided in Unit VI. of the SUPPLEMENTARY
INFORMATION.
FOR FURTHER INFORMATION CONTACT: Susan Stanton, Registration Division
(7505C), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW.,Washington, DC 20460-0001; telephone
number: (703) 305-5218; e-mail address: stanton.susan@epa.gov.
SUPPLEMENTARY INFORMATION:
I. General Information
A. Does this Action Apply to Me?
You may be affected by this action if you are an agricultural
producer; food/feed or beverage manufacturer, wholesale or retailer;
restaurant owner/worker; or pesticide manufacturer. Potentially
affected entities may include, but are not limited to:
[sbull] Crop producers (NAICS 111), e.g., tree fruit and nut
growers, tomato growers and herb producers
[sbull] Animal producers (NAICS 112), including cattle, sheep,
swine, dairy, and poultry producers
[sbull] Food and beverage manufacturers (NAICS 311), including
canners, bottlers, brewers, bakers and other food and beverage
processors
[sbull] Food and beverage stores (NAICS 445)
[sbull] Restaurants (NAICS 722)
[sbull] Pesticide manufacturers (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 Get Copies of this Document and Other Related Information?
1. Docket. EPA has established an official public docket for this
action under docket identification (ID) number OPP-2002-0358. The
official public docket consists of the documents specifically
referenced in this action, any public comments received, and other
information related to this action. Although a part of the official
docket, the public docket does not include Confidential Business
Information (CBI) or other information whose disclosure is restricted
by statute. The official public docket is the collection of materials
that is available for public viewing at the Public Information and
Records Integrity Branch (PIRIB), Rm. 119, Crystal Mall 2,
1921 Jefferson Davis Hwy., 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.
2. Electronic access. 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 http://www.access.gpo.gov/nara/cfr/cfrhtml_00/Title_40/40cfr180_00.html
, a
beta site currently under development. To access the OPPTS Harmonized
Guidelines referenced in this document, go directly to the guidelines
at http://www.epa.gov/opptsfrs/home/guidelin.htm.
An electronic version of the public docket is available through
EPA's electronic public docket and comment system, EPA Dockets. You may
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public
comments, access the index listing of the contents of the official
public docket, and to access those documents in the public docket that
are available electronically. Although not all docket materials may be
available electronically, you may still access any of the publicly
available docket materials through the docket facility identified in
Unit I.B.1. Once in the system, select ``search,'' then key in the
appropriate docket ID number.
II. Background and Statutory Findings
In the Federal Register of February 15, 2002 (67 FR 7159-7163)
(FRL-6823-3); February 14, 2001 (66 FR 10289-10292) (FRL-6768-7); and
April 25, 2001 (66 FR 20811-20815) (FRL-6778-4), EPA issued notices
pursuant to section 408 of FFDCA, 21 U.S.C. 346a, as amended by FQPA
(Public Law 104-170), announcing the filing of pesticide petitions (PP
2F6390, 6F3454, 0E6216 and 1F6266) by FMC Corporation; (PP 6E4630,
0E6157, 1E6330 and 2E6402) by the Interregional Research Project Number
4 (IR-4); and (PP 1E6234) by the Taipei Economic and Cultural
Representative Office. These notices included summaries of the
petitions prepared by FMC Corporation, the registrant. There were no
comments received in response to the notices of filing.
These petitions requested that 40 CFR 180.442 be amended by
establishing tolerances for residues of the insecticide bifenthrin, (2-
methyl[1,1'-biphenyl]-3-yl)methyl-3-(2-chloro-3,3,3-trifluoro-1-
propenyl)-2,2-dimethylcyclopropane-carboxylate, as follows:
1. PP 2F6390 proposed establishment of a tolerance for food
products in food handling establishments at 0.01 ppm.
2. PP 6F3454 proposed establishment of a tolerance for pears at 1.0
ppm; almond hulls at 2 ppm; and tree nuts crop group at 0.05 ppm.
3. PP 0E6216 proposed establishment of a tolerance for imported
bananas at 0.1 ppm.
4. PP 1F6266 proposed establishment of a tolerance for citrus whole
fruits, citrus dried pulp, citrus cold pressed oil and citrus juice at
0.05 ppm.
5. PP 6E4630 proposed establishment of a tolerance for leaf
petioles subgroup (4B) at 2.0 ppm.
6. PP 0E6157 proposed establishment of a tolerance for herb
subgroup (19A) at 0.05 ppm.
7. PP 1E6330 proposed establishment of a tolerance for tomato at
0.15 ppm.
[[Page 23057]]
8. PP 2E6402 proposed establishment of a tolerance for spinach at
0.2 ppm.
9. PP 1E6234 proposed establishment of a tolerance for carambola
(starfruit) at 1.0 ppm.
The residue chemistry data submitted in support of PP 6E4630 (leaf
petioles subgroup) and PP 1E6234 (carambola) were determined by EPA to
be insufficient to support the proposed tolerances. PP 1E6234 was
subsequently withdrawn by the Taipei Economic and Cultural
Representative Office. The requested tolerance for the leaf petioles
subgroup (PP 6E4630) cannot be established until adequate residue
chemistry data are submitted and reviewed.
Based on EPA's review, the remaining petitions described in Unit II
were revised by the petitioners (FMC Corporation and IR-4) to propose
tolerances for residues of bifenthrin in or on almond, hulls at 2.0
ppm; banana at 0.1 ppm; fruit, citrus, group at 0.05 ppm; herb subgroup
at 0.05 ppm; pear at 0.5 ppm; nut, tree, group at 0.05 ppm; spinach at
0.2 ppm; tomato at 0.15 ppm; and food/feed products in food/feed
handling establishments at 0.05 ppm. The revisions were requested for
the following reasons:
EPA determined that the tolerance for pear should be set at 0.5
ppm, not 1.0 ppm as the petitioner originally proposed, based on the
results of submitted field residue data, showing a maximum residue of
0.38 ppm. EPA determined that the tolerance for food/feed products in
food/feed handling establishments should be set at 0.05 ppm, the limit
of quantitation (LOQ) of the analytical method, rather than 0.01 ppm,
the limit of detection (LOD), as the petitioner originally proposed. It
is Agency policy to use the LOQ for setting tolerances when detectable
residues are not found in the residue trials. No other changes to the
originally proposed tolerance levels were requested; however, EPA did
request minor changes in commodity terms to reflect current
nomenclature practices.
Although EPA requested changes to the initial petitions, the nature
of the changes is not considered significant. Therefore, EPA is issuing
this as a final action.
EPA is also deleting time-limited tolerances established for
residues of bifenthrin in or on citrus, dried pulp, at 0.3 ppm, citrus
oil at 0.3 ppm and citrus, whole fruit, at 0.05 ppm in connection with
section 18 emergency exemptions granted by EPA. With the establishment
of the citrus fruit group tolerance (PP 1F6266), these tolerances are
no longer needed.
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....''
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).
III. Aggregate Risk Assessment and Determination of Safety
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 and to
make a determination on aggregate exposure, consistent with section
408(b)(2) of the FFDCA, for a tolerance for residues of bifenthrin in
or on almond, hulls at 2.0 ppm; banana at 0.1 ppm; fruit, citrus, group
10 at 0.05 ppm; herb subgroup 19A at 0.05 ppm; pear at 0.5 ppm; nut,
tree, group 14 at 0.05 ppm; spinach at 0.2 ppm; tomato at 0.15 ppm; and
food/feed products in food/feed handling establishments at 0.05 ppm.
EPA's assessment of exposures and risks associated with establishing
the tolerance follows.
A. Toxicological Profile
EPA has evaluated the available toxicity data and considered its
validity, completeness, and reliability as well as the relationship of
the results of the studies to human risk. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and
children. The nature of the toxic effects caused by bifenthrin are
discussed in Table 1 of this unit as well as the no-observed-adverse-
effect-level (NOAEL) and the lowest-observed-adverse-effect-level
(LOAEL) from the toxicity studies reviewed.
Table 1.--Subchronic, Chronic, and Other Toxicity
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Guideline Number Study Type Results
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870.3100 90-Day Oral Toxicity - Rat NOAEL = 3.8 mg/kg/day (males); 4.3 mg/kg/
(1984) day (females)
LOAEL = 7.5 mg/kg/day (males), 8.5 mg/kg/
day (females), based on increased
incidence of tumors.
Classification: Acceptable-Guideline
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870.3150 90-Day Oral Toxicity - Dog NOAEL = 2.21 mg/kg/day (males and females)
(1984) LOAEL = 4.42 mg/kg/day (males and females)
based on increased incidence of tremors.
Classification: Acceptable-Guideline
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870.3700 Developmental Toxicity Maternal Toxicity
(Gavage; corn oil NOAEL = 0.88 mg/kg/day
vehicle) - Rat (1983) LOAEL = 1.77 mg/kg/day based on tremors
during gestation.
Developmental Toxicity
NOAEL = not determined (fetuses not
examined)
LOAEL = not determined (fetuses not
examined)
Classification: Acceptable-Guideline
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[[Page 23058]]
870.3700 Developmental Toxicity Maternal Toxicity
(Gavage; corn oil NOAEL = 0.88 mg/kg/day
vehicle) - Rat (1984) LOAEL = 1.77 mg/kg/day based on tremors
during gestation.
Developmental Toxicity
NOAEL = 0.88 mg/kg/day
LOAEL = 1.77 mg/kg/day based on increased
fetal and litter incidence of hydroureter
without nephrosis.
Classification: Acceptable-Guideline
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870.3700 Developmental Toxicity Maternal Toxicity
(Dietary) - Rat (2001) NOAEL = 7.1 mg/kg/day
LOAEL = 15.5 mg/kg/day based clinical signs
and decreased food consumption, body
weight gains, and body weight gains
adjusted for gravid uterine weight.
Developmental Toxicity
NOAEL = 15.5 mg/kg/day
LOAEL = not observed.
Classification: Acceptable-Guideline
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870.3700 Developmental Toxicity - Maternal Toxicity
Rabbit (1984) NOAEL = 2.36 mg/kg/day
LOAEL = 3.5 mg/kg/day based on treatment-
related head and forelimb twitching.
Developmental Toxicity
NOAEL = greater than 7 mg/kg/day
LOAEL = not observed
Classification: Acceptable-Guideline
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870.3800 Multigeneration Parental/Systemic Toxicity
Reproductive Toxicity - NOAEL = 3.0 mg/kg/day for females and 5.0
Rat (1986) mg/kg/day for males
LOAEL = 5.0 mg/kg/day for females, based on
tremors and decreased body weight; not
observed for males.
Reproductive/offspring Toxicity
NOAEL = not observed.
LOAEL = not observed.
Classification: Acceptable-Guideline
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870.4100 Chronic Toxicity - Dog NOAEL = 1.3 mg/kg/day (males and females)
(1985) LOAEL = 2.7 mg/kg/day (males and females)
based on increased incidence of tremors.
Classification: Acceptable-Guideline
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870.4300 Combined Chronic Toxicity/ NOAEL = 3.0 mg/kg/day (females); 4.7 mg/kg/
Carcinogenicity - Rat day (males)
(1986) LOAEL = 6.1 mg/kg/day (females), based on
increased incidence of tremors; 9.7 mg/kg/
day (males), based on increased incidence
of tremors.
Carcinogenicity - No conclusive evidence of
carcinogenic potential.
Classification: Acceptable-Guideline
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870.4200 Carcinogenicity - Mice NOAEL = 6.7 mg/kg/day (males); 8.8 mg/kg/
(1986) day (females)
LOAEL = 25.6 mg/kg/day (males) and 32.7 mg/
kg/day (females), based on increased
incidence of tremors.
Carcinogenicity - carcinogenic potential
was evidenced by a dose-related increased
in the incidence of leiomyosarcomas in the
urinary bladder, a significant dose-
related trend for combined hepatocellular
adenomas and carcinomas in males, and a
significantly higher incidence of combined
lung adenomas and carcinomas in females.
Classification: Acceptable-Guideline
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870.6200 Acute Neurotoxicity - Rat NOAEL = 35 mg/kg (32.8 mg ai/kg/day).
LOAEL = 75 mg/kg (70.3 mg ai/kg/day) based
on mortality (females only), clinical and
functional operational battery (FOB)
findings and differences in motor
activity.
Classification: Acceptable-Guideline
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870.6200 Subchronic Neurotoxicity - NOAEL = 50 ppm (equivalent to 2.9 mg/kg/day
Rat in males and 3.7 mg/kg/day in females).
LOAEL =100 ppm (equivalent to 6.0 mg/kg/day
in males and 7.2 mg/kg/day in females)
based on neuromuscular findings (tremors,
changes in grip strength and landing foot-
splay).
Classification: Acceptable-Guideline
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870.3200 Dermal Toxicity - Rabbit NOAEL = 88 mg ai/kg/day (males and females)
LOAEL = 442 mg ai/kg/day (males and
females), based on loss of muscle
coordination and increased incidence of
tremors.
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[[Page 23059]]
870.3200 Dermal Toxicity - Rat NOAEL = 47 mg ai/kg/day (males and females)
LOAEL = 93 mg ai/kg/day (males and
females), based on loss of muscle
coordination and increased incidence of
tremors.
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870.7485 Metabolism - Rat Very little of the administered radioactive
dose was expired as 14C-CO2 (0.028% for
males and 0.053% for females). The
majority (about 70%) of the administered
radioactivity was found in the feces with
about 20% in the urine. A complication of
this study is that males were administered
a radioactive dose with the label in the
acid position, while females were
administered a radioactive dose with the
label in the alcohol position. This could
make comparisons between males and females
difficult. Despite the difference in 14C-
labeling position in the bifenthrin
administered to males and females, the
study is acceptable. This conclusion is
based on the fact that most (>90%) of the
radioactivity was eliminated via the urine
and feces, with no significant differences
between the sexes in this respect.
Further, there were no significant
differences between dosage groups in
percentages excreted. This suggests that
most of the compound is excreted with
little or no change, or in a form
incorporating both of the labeled sites.
The results also show that females
retained slightly more radioactivity in
their bodies (particularly in adipose
tissue) than did males, particularly at
the high-dose. Labeling of the material
given to the females was in the biphenyl
group, and, given a splitting of the
molecule between the two labeling sites,
this would have tended to give a more
lipophilic radiolabeled residue.
Classification: Acceptable-Guideline
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870.7485 Metabolism - Rat Plasma radioactivity in the low-dose (4 mg/
kg) animals after dosing slowly rose,
indicating a slow rate of absorption from
the gastrointestinal tract. The half-life
of absorption was calculated to be about
1.5 hours, with a lag-time of 0.5 hours
following first order kinetics.
Radioactivity peaked in plasma for low-
dose animals in 4 hours. The elimination
of 14C-bifenthrin from the plasma was
equally slow, with significant
radioactivity still remaining in blood at
72 hours. Plasma radioactivity in the high-
dose (35 mg/kg) animals appeared to follow
a similar course as seen in the low-dose
animals. The peak radioactivity for the
high-dose group appeared to be somewhat
delayed, peaking at about 6 hours.
Significant radioactivity still remained
after 72 hours in the high-dose animals.
Classification: Acceptable-Guideline
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870.7485 Metabolism - Rat The major metabolic route of radiolabeled
bifenthrin appeared to be hydrolysis of
the ester linkage with oxidation of the
resulting alcohol to the acid. Protein
binding of radioactive components or
metabolites appears to increase with time.
Classification: Acceptable-Guideline
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870.7485 Metabolism - Rat Fat and skin half-lives were the longest
with half-lives of 51 and 50 days,
respectively. The half-lives for ovaries,
liver, kidneys and sciatic nerve were
37.4, 19.0, 28.5, and 42 days,
respectively. Radioactive components were
measured in fat at numerous time
intervals, before and after daily dosing.
The major component in fat is parent
compound with a half-life of 47.5 days.
Other unidentified components included a
somewhat polar (Rf = 0.65) compound and
two other relatively minor components.
Classification: Acceptable-Guideline
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870.7485 Metabolism - Rat Within 7 days, nearly all bifenthrin and/or
metabolites were excreted in either urine
or feces. The majority of radioactivity
was excreted in the feces within 48 hours.
Tissues that retained bifenthrin and/or
metabolites beyond 7 days included fat and
skin in males and females, and gonads in
females.
Classification: Unacceptable-Guideline.
Although the number of animals/group in
this study was 3, and not 5/sex/group as
recommended by guidelines, and a quality
assurance statement was lacking, the
results of this study provide useful
information.
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[[Page 23060]]
870.7485 Metabolism - Rat Results showed minimal breakage of the
ester linkage of the parent compound in
the material eliminated via the feces in
the period of 0-48 hours after dosage,
when most of the administered
radioactivity is identifiable as coming
from unmodified parent compound. However,
the material was subsequently eliminated,
although a relatively small proportion of
the administered dose appears to have
undergone more modification. Since a
greater proportion of the radioactivity
was eliminated via the feces in the period
of 48-168 hours in the form of 2-Methyl-3-
phenylbenzyl alcohol and 2-Methyl-3-
phenylbenzoic acid than the parent
compound, this is evidence that extensive
breakage of the ester linkage does occur,
either in the material retained in the
intestines for more than 46 hours, or in
the material absorbed and subsequently
eliminated via the feces.
Classification: Unacceptable-Guideline.
While this study is limited, it dose
provide some insight into the incomplete
absorption of bifenthrin from the
intestine, and the lack of modification of
most of the unabsorbed material,
particularly that eliminated via the feces
during the period of 0-48 hours. However,
the metabolism of the absorbed compound
(radioactivity primarily excreted via the
urine, despite differences in labeling) is
less clear.
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870.7485 Metabolism - Rat The results of the study demonstrated that
the majority of radioactivity excreted in
the feces was the parent compound and its
intact hydroxylated metabolites. Much of
the radioactivity excreted in urine was
hydrolytic and hydrolytic/oxidative
degradation products of the parent
compound.
Classification: Unacceptable-Guideline.
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870.7600 Dermal Penetration - Rats For animals in group A, means of 4.6, 14.2,
12.8 and 14.7% total dose were recovered
from the skin at 0, 4, 10 and 24 hours
post-dose; corresponding percentages in
the wash were 94.6, 80.8, 78.6 and 70%.
For animals in group B, means of 20.0,
37.9, 42.0 and 41.2% remained (and were
recovered from) the skin at 0, 4, 10 and
24 hours post-dose; corresponding
percentages in the wash were 73.9, 50.6,
41.3 and 37.7% respectively.
This dermal absorption study is classified
as acceptable. However, because only one
dose was used, this study, by itself, does
not satisfy the guideline requirement for
a dermal penetration study in the rat for
technical bifenthrin (FMC 54800). However,
it can be used, in conjunction with other
dermal penetration studies, as supporting
data for the purposes of registration and/
or reregistration of products containing
or consisting of bifenthrin.
----------------------------------------------------------------------------------------------------------------
870.7600 Dermal Penetration - Rats Means of 96.83, 84.75, 76.86 and 72.88% of
the radioactivity were recovered in the
skin wash at 0, 4, 10 and 24 hours post
dosage, respectively. By the time the 4-
hour post-dose and later skin samples were
collected the emulsifying solvents had
evaporated. Means of 4.04, 12.00, 16.55
and 19.44% total dose were recovered from
the washed skin of the application site at
0, 4, 10 and 24 hours respectively;
corresponding mean percentages recovered
from the carcass were 0.09, 0.87, 0.85 and
1.67%. Mean percentages recovered in urine
and feces were 0, 0.14, 0.43 and 3.23%.
This dermal absorption study is classified
as acceptable. However, because only one
dose was used, this study, by itself, does
not satisfy the guideline requirement for
a dermal penetration study in the rat for
technical bifenthrin (FMC 54800). However,
it can be used, in conjunction with other
dermal penetration studies, as supporting
data for the purposes of registration and/
or reregistration of products containing
or consisting of bifenthrin.
----------------------------------------------------------------------------------------------------------------
870.7600 Dermal Penetration - Rats In general, only very small amounts of
radioactivity were present in blood,
excrement, and carcasses, with almost all
(approximately 99%) of the absorbed
radioactivity localized in skin at the
application site, and in the skin adjacent
to the application site. Average
percentages of FMC 54800 dosages absorbed
at 10 hours were 55.8%, 54.1%, and 37.5%
for the 49.2, 514 and 5253 [mu]g/rat
groups respectively. Corresponding
percentages for the 3 groups at the 0.5
hour sacrifice were 54.6%, 56.4%, and
52.5%, so the percentage absorption of FMC
54800 did not seem to depend on time-to-
sacrifice. At 10 hours and the lowest dose
level, the percentages present were as
follows: excreta: <0.44%; carcass: <1.8%;
skin at application site: 50.3%; skin
adjacent to application site: 5.5%. At 10
hours and the highest dose level, the
percentages of total dose present were as
follows: excreta: 0.07%; carcass: 0.5%;
skin at application site: 34.6%; skin
adjacent to application site: 2.7%.
Classification: This dermal absorption
study is classified as acceptable.
However, by itself, does not satisfy the
guideline requirement for a dermal
penetration study in the rat for technical
bifenthrin (FMC 54800). However, it can be
used, in conjunction with other dermal
penetration studies, as supporting data
for the purposes of registration and/or
reregistration of products containing or
consisting of bifenthrin.
----------------------------------------------------------------------------------------------------------------
[[Page 23061]]
870.7600 Dermal Penetration - Rats The report states that at 24 hours
postdose, 5.11% of the dose was absorbed
(application-site skin + carcass + urine +
feces) in this second trial. However, it
is noted that there was poor recovery (68%
of the total dose) from one of the rats
(C32545) sacrificed at 24 hours in the
second trial; disregarding the findings
from this one animal then the mean value
of the dose that was absorbed was 5.88%,
and this can be taken as a reasonable
estimate of the dermal absorption at this
dose level.
This dermal absorption study is classified
as acceptable. However, because only one
dose was used, this study, by itself, does
not satisfy the guideline requirement for
a dermal penetration study in the rat for
technical bifenthrin (FMC 54800). However,
it can be used, in conjunction with other
dermal penetration studies, as supporting
data for the purposes of registration and/
or reregistration of products containing
or consisting of bifenthrin.
----------------------------------------------------------------------------------------------------------------
B. Toxicological Endpoints
The dose at which no adverse effects are observed (the NOAEL) from
the toxicology study identified as appropriate for use in risk
assessment is used to estimate the toxicological level of concern
(LOC). However, the lowest dose at which adverse effects of concern are
identified (the LOAEL) is sometimes used for risk assessment if no
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. In this
case, EPA has determined that an additional 10X data base uncertainty
factor (UFDB) is needed to account for the lack of a
developmental neurotoxicity (DNT) study when assessing acute (single
dose) exposure scenarios. EPA has further determined that for repeated
dose exposure scenarios (i.e., chronic dietary; short- and
intermediate-term incidental oral; and short-, intermediate-, and long-
term dermal and inhalation scenarios) a 3X UFDB is adequate
to account for the lack of the DNT study. The factors which EPA
considered in making these determinations are discussed in detail below
in Unit III.D.3.
For dietary risk assessment (other than cancer) the Agency uses the
UF to calculate an acute or chronic reference dose (acute RfD or
chronic RfD) where the RfD is equal to the NOAEL divided by the
appropriate UF (RfD = NOAEL/UF). Where an additional safety factor (SF)
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 LOC. For example, when 100 is the appropriate UF (10X
to account for interspecies differences and 10X for intraspecies
differences) the LOC is 100. In this case, since 300 is the appropriate
UF for repeated dose exposure scenarios (10X to account for
interspecies differences;10X for intraspecies differences and 3X for
data base uncertainty) the LOC is 300. 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 x 10-6 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 (MOEcancer = point of
departure/exposures) is calculated. A summary of the toxicological
endpoints for bifenthrin used for human risk assessment is shown in
Table 2 of this unit:
Table 2.--Summary of Toxicological Dose and Endpoints for Bifenthrin for Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
FQPA SF* and Level of
Exposure Scenario Dose Used in Risk Concern for Risk Study and Toxicological
Assessment, UF Assessment Effects
----------------------------------------------------------------------------------------------------------------
Acute Dietary (General population NOAEL = 32.8 mg ai/kg FQPA SF = 1X Acute Neurotoxicity
including infants and children) UF = 1,000............. aPAD = acute RfD / FQPA Study in Rats
Acute RfD = 0.033 mg/kg/ SF = 0.033 mg/kg/day. LOAEL = 70.3 mg/kg/day
day. based on observations
of mortality (females
only), clinical and
functional operational
battery (FOB) findings
and differences in
motor activity.
----------------------------------------------------------------------------------------------------------------
Chronic Dietary (All populations) NOAEL = 1.3 mg/kg/day FQPA SF = 1X 1-Year Oral Study in
UF = 300............... cPAD = chronic RfD / Dogs
Chronic RfD = 0.004 mg/ FQPA SF = 0.004 mg/kg/ LOAEL = 2.7 mg/kg/day
kg/day. day. based on observations
of increased incidence
of tremors in both
sexes.
----------------------------------------------------------------------------------------------------------------
[[Page 23062]]
Incidental Oral Short-Term (1 - 30 NOAEL = 2.21 mg ai/kg/ FQPA SF = 1X 90-Day Oral Study in
Days) Residential Only day LOC for MOE = 300...... Dogs
UF = 300............... LOAEL = 4.42 mg ai/kg/
day based on
observations of
increased incidence of
tremors in both sexes.
----------------------------------------------------------------------------------------------------------------
Incidental Oral Intermediate-Term (1 - NOAEL = 2.21 mg ai/kg/ FQPA SF = 1X 90-Day Oral Study in
6 Months) Residential Only day LOC for MOE = 300...... Dogs
UF = 300............... LOAEL = 4.42 mg ai/kg/
day based on
observations of
increased incidence of
tremors in both sexes.
----------------------------------------------------------------------------------------------------------------
Short-Term Dermal (1 to 30 days) dermal study NOAEL = 47 FQPA SF = 1X 21-Day Dermal Study in
(Residential) mg/kg/day LOC for MOE = 300 Rats
(Residential). LOAEL = 93 mg/kg/day
based on observations
of clinical signs
(staggered gait and
exaggerated hindlimb
flexion).
----------------------------------------------------------------------------------------------------------------
Intermediate-Term Dermal (1 to 6 dermal study NOAEL = 47 FQPA SF = 1X 21-Day Dermal Study in
months) (Residential) mg/kg/day LOC for MOE = 300 Rats
(Residential). LOAEL = 93 mg/kg/day
based on observations
of clinical signs
(staggered gait and
exaggerated hindlimb
flexion).
----------------------------------------------------------------------------------------------------------------
Long-Term Dermal (several months to dermal study NOAEL = 47 FQPA SF = 1X 21-Day Dermal Study in
lifetime) (Residential) mg/kg/day LOC for MOE = 300 Rats
(Residential). LOAEL = 93 mg/kg/day
based on observations
of clinical signs
(staggered gait and
exaggerated hindlimb
flexion).
----------------------------------------------------------------------------------------------------------------
Short-Term Inhalation (1 to 30 days) oral study NOAEL = 2.21 FQPA SF = 1X 90-Day Oral Study in
(Residential) mg/kg/day LOC for MOE = 300 Dogs
(Residential). LOAEL = 4.42 mg/kg/day
based on observations
of increased incidence
of tremors in both
sexes.
----------------------------------------------------------------------------------------------------------------
Intermediate-Term Inhalation (1 to 6 oral study NOAEL = 2.21 FQPA SF = 1X 90-Day Oral Study in
months) (Residential) mg/kg/day LOC for MOE = 300 Dogs
(Residential). LOAEL = 4.42 mg/kg/day
based on observations
of increased incidence
of tremors in both
sexes.
----------------------------------------------------------------------------------------------------------------
Long-Term Inhalation (several months oral study NOAEL = 1.3 FQPA SF = 1X 1-Year Oral Study in
to lifetime) (Residential) mg/kg/day LOC for MOE = 300 Dogs
(Residential). LOAEL = 2.7 mg/kg/day
based on observations
of increased incidence
of tremors in both
sexes.
----------------------------------------------------------------------------------------------------------------
Cancer (oral, dermal, inhalation) EPA's Carcinogenicity Peer Review Committee (CPRC) has characterized
bifenthrin as a Category C (possible human) carcinogen, primarily on the
basis of the mouse carcinogenicity study in which the high-dose males
(81.3 mg/kg/day) showed a highly significant increased incidence of
urinary bladder tumors. Other findings in the mouse study included a
dose-related trend of increased combined incidences of adenoma and
adenocarcinoma of the liver (males only), and increased incidences of
bronchioalveolar adenomas and adenocarcinomas of the lung in females at
some, but not all, doses relative to their controls. The Agency did not
recommend assignment of a Q1* but has determined that the reference dose
(RfD) approach should be used for quantification of human risk.
----------------------------------------------------------------------------------------------------------------
*The reference to the FQPA SF refers to any additional SF retained due to concerns unique to the FQPA.
C. Exposure Assessment
1. Dietary exposure from food and feed uses. Tolerances have been
established (40 CFR 180.442) for the residues of bifenthrin in or on a
variety of raw agricultural commodities. Tolerances have been
established on plant commodities ranging from 0.05 ppm for corn grain,
peas, beans and eggplant to 10 ppm for dried hops and on animal
commodities ranging from 0.01 ppm for meat byproducts to 1.0 ppm for
milk fat and fat of cattle, goats, hogs, horses, and sheep. Risk
assessments were conducted by EPA to assess dietary exposures from
bifenthrin 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 one day
or single exposure. The Dietary Exposure Evaluation Model (DEEM[reg])
analysis evaluated the individual food consumption as reported by
respondents in the USDA 1989-1992 nationwide Continuing Surveys of Food
Intake by Individuals (CSFII) and accumulated exposure to the chemical
for each commodity. The following assumptions were made for the acute
exposure assessments: A probabilistic dietary exposure assessment was
conducted for the general U.S. population and all population subgroups,
including infants and children. The highly refined assessment
incorporated the most recent USDA Pesticide Data Program (PDP)
monitoring data, field trial data and processing factor data (for
grapes and pending uses). It assumed 100% crop treated for the new and
existing uses.
ii. Chronic exposure. In conducting this chronic dietary risk
assessment the DEEM[reg] analysis evaluated the
[[Page 23063]]
individual food consumption as reported by respondents in the USDA
1989-1992 nationwide CSFII and accumulated exposure to the chemical for
each commodity. The following assumptions were made for the chronic
exposure assessments: A highly refined chronic exposure assessment was
conducted which incorporated the most recent PDP monitoring data, field
trial data and processing factor data (for grapes and pending uses). It
assumed 100% crop treated for the new and existing uses.
iii. Cancer. Bifenthrin has been classified as a Category C
(possible human) carcinogen. The Agency has determined that the
reference dose (RfD) approach should be used for quantification of
human risk. For further discussion of the weight-of-the-evidence
considered by EPA in making this determination, see the proposed rule
for Bifenthrin tolerances (59 FR 9167, February 25, 1994) (FRL-4756-1).
Under this approach, chronic dietary exposures that are less than the
RfD (or cPAD) are assumed to be protective for cancer dietary exposure
as well. Therefore, a separate cancer dietary risk assessment was not
conducted.
iv. Anticipated residue and percent crop treated (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 did not use percent crop treated information for
assessing dietary risk from bifenthrin.
2. Dietary exposure from drinking water. The Agency lacks
sufficient monitoring exposure data to complete a comprehensive dietary
exposure analysis and risk assessment for bifenthrin 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 bifenthrin.
The Agency uses the FQPA Index Reservoir Screening Tool (FIRST) or
the Pesticide Root Zone/Exposure Analysis Modeling System (PRZM/EXAMS),
to produce estimates of pesticide concentrations in an index reservoir.
The SCI-GROW model is used to predict pesticide concentrations in
shallow groundwater. For a screening-level assessment for surface water
EPA will use FIRST, a tier 1 model, before using PRZM/EXAMS, a tier 2
model. The FIRST model is a subset of the PRZM/EXAMS model that uses a
specific high-end runoff scenario for pesticides. While both FIRST and
PRZM/EXAMS incorporate an index reservoir environment, the PRZM/EXAMS
model includes a percent crop area factor as an adjustment to account
for the maximum percent crop 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 bifenthrin they are further
discussed in the aggregate risk sections in Unit III.E.
Based on the FIRST and SCI-GROW models the estimated environmental
concentrations (EECs) of bifenthrin for acute exposures are estimated
to be 0.1 parts per billion (ppb) for surface water and 0.006 ppb for
ground water. The EECs for chronic exposures are estimated to be 0.1
ppb for surface water and 0.006 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).
Bifenthrin is currently registered for use on the following
residential non-dietary sites: ornamental gardens, lawns, turf, and
general insect control in, around and on buildings, structures, and
immediate surroundings. There are also uses for spot treatments and
crack and crevice treatments for insects in, on, and around homes,
buildings, and other structures and for subsoil treatment around
structures for control of termites (termiticide use). The risk
assessment was conducted using the following residential exposure
assumptions: Adults and children are potentially exposed to bifenthrin
residues after application of bifenthrin products in residential
settings. Short- and intermediate-term post-application dermal
exposures for adults, and short- and intermediate-term post-application
dermal and incidental oral exposures for children are anticipated. Risk
estimates were generated for potential contact with lawn, soil, and
treated indoor surfaces using EPA's Draft Standard Operating Procedures
for Residential Exposure Assessment; and for the lawn exposure
scenarios, dissipation data from a chemical specific turf transferable
residue (TTR) study. Indoor surface residues in homes were based on
crack and crevice data collected for bifenthrin and another
insecticide, malathion. These estimates are considered conservative
screening level estimates, since the study data were adjusted to
reflect maximum application rates.
4. Cumulative effects from substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) of the FFDCA
[[Page 23064]]
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 bifenthrin has a common mechanism of toxicity with other
substances. Unlike other pesticides for which EPA has followed a
cumulative risk approach based on a common mechanism of toxicity, EPA
has not made a common mechanism of toxicity finding as to bifenthrin
and any other substances and bifenthrin 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 bifenthrin 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 policy statements released by EPA's Office of
Pesticide Programs concerning common mechanism determinations and
procedures for cumulating effects from substances found to have a
common mechanism on EPA's Web site at http://www.epa.gov/pesticides/cumulative/
.
D. 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. Prenatal and postnatal sensitivity. EPA concluded that there is
not a concern for pre- and/or postnatal toxicity resulting from
exposure to bifenthrin. There was no quantitative or qualitative
evidence of increased susceptibility of rat or rabbit fetuses to in
utero exposure to Bifenthrin in developmental toxicity studies and no
quantitative or qualitative evidence of increased susceptibility of
neonates (as compared to adults) to bifenthrin in a 2-generation
reproduction study in rats. In addition, there are no concerns or
residual uncertainties for pre and/or post-natal toxicity following
exposure to Bifenthrin.
3. Conclusion. No special FQPA safety factor is needed based on
concerns for pre- and/or postnatal toxicity to bifenthrin. However, EPA
has concluded that in light of the lack of the DNT study there is no
reliable basis for removing the additional FQPA 10X safety factor when
assessing acute (single dose) exposure scenarios. The following points
were considered in this determination:
i. It is assumed that the DNT study will be conducted at dose
levels similar to those used in the rat reproduction study with
Bifenthrin wherein the offspring NOAEL was 5.0 mg/kg/day, the highest
dose tested (no effects were observed in offspring at this dose); but
that the DNT study would not be conducted at dose levels higher than 10
mg/kg/day since a range-finding study indicates excessive fetotoxicity
occurred at this dose (all pups from 2 of the 4 litters at 10 mg/kg/day
died within 14 days of birth).
ii. The DNT study may impact the currently selected acute
regulatory dose since the NOAEL used to establish the acute Reference
dose for dietary risk assessment is 33 mg/kg/day, a level which is more
than 5-fold higher than the offspring NOAEL in the rat reproduction
study of 5.0 mg/kg/day ( a level which is similar to dose levels likely
to be used in the DNT study).
EPA has further determined that for repeated dose exposure
scenarios a 3X UFDB is adequate to account for the lack of
the DNT study. Repeated dose exposure scenarios include chronic dietary
exposure; short-term (repeated exposure up to 30 days) and
intermediate-term (repeated exposure from 1 to 6 months) incidental
oral exposure; and short-term, intermediate-term, and long-term
(several months to lifetime) dermal and inhalation exposure scenarios.
EPA's determination that a 3X UFDB is adequate for repeated
dose exposure scenarios is based on the following considerations:
a. As stated above, the DNT study will likely be conducted at dose
levels similar to the rat reproduction study.
b. The results of the DNT study are not expected to impact the
current regulatory doses selected for repeated exposure scenarios since
the NOAELs used for these risk assessment endpoints (e.g., 1.3 mg/kg/
day from the chronic dog study for chronic RfD) are approximately 4-
fold lower than the offspring NOAEL (5.0 mg/kg/day) in the rat
reproduction study conducted with Bifenthrin. Although the results of
the DNT are not expected to impact the current regulatory dose given
the 4-fold difference observed in the rat and dog studies, EPA does not
have sufficient reliable data to apply no additional FQPA safety
factor. Rather, EPA believes that the 4X difference between the
offspring NOAEL in the rat reproduction study and the NOAELs used for
risk assessment endpoints provides reliable data supporting a 3X UF for
repeated dose exposure scenarios. The use of a 3X provides roughly a
10-fold difference between the NOAEL associated with the identified
effects in the rat necessitating the DNT study and the NOAELs used for
setting regulatory doses. Therefore, a UFDB of 3X will be
applied as a FQPA safety factor to repeated dose exposure scenarios to
account for the lack of the DNT study with Bifenthrin.
E. 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 + residential 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 are used to calculate DWLOCs: 2 liter (L)/
70 kg (adult male), 2L/60 kg (adult female), and 1L/10 kg (child).
Actual body weights and drinking water consumption values vary on an
individual basis. This variation will be 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
[[Page 23065]]
calculated DWLOCs, EPA concludes with reasonable certainty that
exposures to the pesticide 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 residues of the pesticide in 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
bifenthrin will occupy 32% of the aPAD for the U.S. population, 19% of
the aPAD for females 13 to 50 years old, 52% of the aPAD for infants
less than 1 year old and 38% of the aPAD for children 1 to 6 years old.
In addition, there is potential for acute dietary exposure to
bifenthrin in drinking water. After calculating DWLOCs and comparing
them to the EECs for surface and ground water, EPA does not expect the
aggregate exposure to exceed 100% of the aPAD, as shown in Table 3 of
this unit:
Table 3.--Aggregate Risk Assessment for Acute Exposure to Bifenthrin
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup aPAD (mg/ % aPAD Water EEC Water EEC Acute DWLOC
kg) (Food) (ppb) (ppb) (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. population 0.033 32 0.1 0.006 780
----------------------------------------------------------------------------------------------------------------
All Infants (<1 year old) 0.033 52 0.1 0.006 160
----------------------------------------------------------------------------------------------------------------
Children (1-6 years old) 0.033 38 0.1 0.006 200
----------------------------------------------------------------------------------------------------------------
Females (13-50 years old) 0.033 19 0.1 0.006 800
----------------------------------------------------------------------------------------------------------------
2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that exposure to
bifenthrin from food will utilize 12% of the cPAD for the U.S.
population, 13% of the cPAD for infants less than 1 year old and 24% of
the cPAD for children 1 to 6 years old. Based on the use pattern,
chronic residential exposure to residues of bifenthrin is not expected.
In addition, there is potential for chronic dietary exposure to
bifenthrin in drinking water. After calculating DWLOCs and comparing
them to the EECs for surface and ground water, EPA does not expect the
aggregate exposure to exceed 100% of the cPAD, as shown in Table 4 of
this unit:
Table 4.--Aggregate Risk Assessment for Chronic Exposure to Bifenthrin
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup cPAD mg/kg/ % cPAD Water EEC Water EEC Chronic
day (Food) (ppb) (ppb) DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. Population 0.004 12 0.1 0.006 120
----------------------------------------------------------------------------------------------------------------
All Infants (<1 year old) 0.004 13 0.1 0.006 35
----------------------------------------------------------------------------------------------------------------
Children (1-6 years old) 0.004 24 0.1 0.006 30
----------------------------------------------------------------------------------------------------------------
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).
Bifenthrin is currently registered for use that could result in
short-term residential exposure and the Agency has determined that it
is appropriate to aggregate chronic food and water and short-term
exposures for bifenthrin.
Using the exposure assumptions described in this unit for short-
term exposures, EPA has concluded that food and residential exposures
aggregated result in aggregate MOEs of 544 to 1,070 for adult male and
female homeowners applying bifenthrin to turf, treating structural wood
or making crack and crevice applications indoors. EPA has further
concluded that food and residential exposures aggregated result in
aggregate MOEs of 354 for children (toddlers) with post-application
exposure outdoors and 694 for children (toddlers) with post-application
exposure following indoor crack and crevice treatments. These aggregate
MOEs do not exceed the Agency's level of concern for aggregate exposure
to food and residential uses. In addition, short-term DWLOCs were
calculated and compared to the EECs for chronic exposure of bifenthrin
in ground and surface water. After calculating DWLOCs and comparing
them to the EECs for surface and ground water, EPA does not expect
short-term aggregate exposure to exceed the Agency's level of concern,
as shown in Table 5 of this unit:
[[Page 23066]]
Table 5.--Aggregate Risk Assessment for Short-Term Exposure to Bifenthrin
----------------------------------------------------------------------------------------------------------------
Aggregate
Aggregate Level of Surface Ground Short-Term
Population Subgroup MOE (Food + Concern Water EEC Water EEC DWLOC (ppb)
Residential) (LOC) (ppb) (ppb)
----------------------------------------------------------------------------------------------------------------
Adult Female: Structural Wood Treatment 544 300 0.1 0.006 100
----------------------------------------------------------------------------------------------------------------
Adult Male: Structural Wood Treatment 546 300 0.1 0.006 120
----------------------------------------------------------------------------------------------------------------
Adult Female: Indoor Crack and Crevice 855 300 0.1 0.006 140
Treatment
----------------------------------------------------------------------------------------------------------------
Adult Male: Indoor Crack and Crevice Treatment 858 300 0.1 0.006 170
----------------------------------------------------------------------------------------------------------------
Children (Toddler): Outdoor Post-application 354 300 0.1 0.006 11
Exposure
----------------------------------------------------------------------------------------------------------------
Children (Toddler): Indoor Post-application 694 300 0.1 0.006 42
Exposure
----------------------------------------------------------------------------------------------------------------
4. Intermediate-term risk. Intermediate-term aggregate exposure
takes into account residential exposure plus chronic exposure to food
and water (considered to be a background exposure level).
Bifenthrin is currently registered for use(s) that could result in
intermediate-term residential exposure and the Agency has determined
that it is appropriate to aggregate chronic food and water and
intermediate-term exposures for bifenthrin. However, since short-term
risk estimates for residential handler and post-application exposures
to bifenthrin represent worst-case risk estimates for intermediate-term
scenarios, separate intermediate-term aggregate risks were not
estimated. Short-term risk estimates are considered to represent worst-
case risk estimates for intermediate-term scenarios for the following
reasons.
The toxic endpoints used to estimate risks for intermediate-term
dermal, incidental oral, and inhalation exposures for bifenthrin are
the same as those used to estimate risks from short-term exposures. In
addition, EPA used the same residue data from outdoor (turf) and indoor
(hard-surface) studies to estimate short and intermediate-term
exposures. Any differences in the exposure estimates are a result of
the assumptions used for activity patterns, which may differ for short
versus intermediate-term exposure depending on the scenario assessed.
As a result of these differences, exposure estimates for intermediate-
term exposure scenarios are either equal to or lower than exposure
estimates for short-term scenarios. Consequently, risk estimates (MOEs)
for intermediate-term exposures are equal to or greater than MOEs for
short-term exposures. Since short-term risk estimates are below levels
of concern, intermediate-term risk estimates are also below levels of
concern.
5. Aggregate cancer risk for U.S. population. Bifenthrin has been
classified as a Category C (possible human) carcinogen. The Agency has
determined that the reference dose (RfD) approach should be used for
quantification of human risk. Therefore, the chronic aggregate risk
assessment described above in Unit III.E.2. also encompasses chronic
aggregate cancer risk from bifenthrin.
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 bifenthrin residues.
IV. Other Considerations
A. Analytical Enforcement Methodology
Adequate enforcement methods are available for determination of the
regulated bifenthrin residue in plants. Crop field trial samples were
analyzed for residues of bifenthrin using FMC Methods P-1073, P-1089,
P-1645M, P-2132M, P-3133, or P-3346. These methods are variations of
two other methods which have been submitted for inclusion in PAM II
(FMC's Methods P-1031 and RAN-0140). These methods have been adequately
validated and are adequate for data collection.
The methods 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
The Codex Alimentarius Commission has established several maximum
residue limits (MRLs) for residues of bifenthrin in/on various
commodities. The Codex MRLs are expressed in terms of bifenthrin per
se. The Codex MRL and the U.S. tolerance expressions are compatible.
Of the new commodities for which tolerances are being established,
Codex MRLS exist only for pear, grapefruit, lemon and orange. The Codex
MRLs of 0.5 ppm for pear and 0.05 ppm for grapefruit, lemon and orange
are compatible with the new U.S. tolerances for pear (0.5 ppm) and
citrus fruit (0.05 ppm). Codex MRLs have not been established for
bananas, herbs, tomatoes, spinach or tree nuts.
The following conclusions can be made regarding efforts to
harmonize existing (i.e., previously established) U.S. tolerances with
Codex MRLs: (i) Compatibility between the U.S. tolerances and Codex
MRLs exists for maize and chicken commodities except eggs; (ii)
incompatibility of the U.S. tolerances and Codex MRLs remains for maize
forage and fodder, strawberry, eggs, and cattle commodities because of
differences in agricultural practices and/or method limits of
quantitation. No questions of compatibility exist with respect to
commodities where Codex MRLs have been established but U.S. tolerances
do not exist.
There are no Canadian MRLs established for bifenthrin. Mexican MRLs
have been established for bifentrin at 0.5 ppm for cottonseed, 0.05 ppm
for maize, and 3 ppm for strawberry. These levels are compatible with
the U.S. tolerance levels.
V. Conclusion
Therefore, tolerances are established for residues of bifenthrin,
(2-methyl[1,1'-biphenyl]-3-yl)methyl-3-(2-chloro-3,3,3-trifluoro-1-
propenyl)-2,2-dimethylcyclopropane-carboxylate, in or on almond, hulls
at 2.0 ppm; banana at 0.1 ppm; fruit, citrus, group 10 at 0.05 ppm;
herb subgroup 19A at 0.05 ppm; pear at 0.5 ppm; nut, tree, group 14 at
0.05 ppm; spinach at 0.2 ppm; tomato at 0.15 ppm; and food/feed
products in food/feed handling establishments at 0.05 ppm.
[[Page 23067]]
VI. 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 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 ID number OPP-2002-0358 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 June 30,
2003.
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 (1900C),
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 Rm. 104, Crystal Mall 2, 1921
Jefferson Davis Hwy., Arlington, VA. 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
(703) 603-0061.
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, PO 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 VI.A., you
should also send a copy of your request to the PIRIB for its inclusion
in the official record that is described in Unit I.B.1. Mail your
copies, identified by docket ID number OPP-2002-0358, 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 Unit I.B.1. 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).
VII. Statutory and Executive Order Reviews
This final rule establishes a tolerance under section 408(d) of the
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 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
[[Page 23068]]
tolerances and exemptions that are established on the basis of a
petition under section 408(d) of the 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. 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 (65 FR
67249, 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.
VIII. 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: April 16, 2003.
Debra Edwards,
Director, Registration Division, Office of Pesticide Programs.
0
Therefore, 40 CFR chapter I is amended as follows:
PART 180--[AMENDED]
0
1. The authority citation for part 180 continues to read as follows:
Authority: 21 U.S.C. 321(q), 346(a) and 371.
0
2. Section 180.442 is amended in paragraph (a) by designating the text
following the paragraph heading as paragraph (a)(1); by adding
alphabetically commodities to the table in newly designated paragraph
(a)(1), by adding paragraph (a)(2), and in the table to paragraph (b)
by deleting the entries for ``Citrus;'' ``Citrus, dried pulp;'' and
``Citrus, oil.''.
Sec. 180.442 Bifenthrin; tolerances for residues.
(a) General. (1) * * *
------------------------------------------------------------------------
Parts per
Commodity million
------------------------------------------------------------------------
Almond, hulls.............................................. 2.0
* * * * *
Banana\1\.................................................. 0.1
* * * * *
Fruit, citrus, group 10.................................... 0.05
* * * * *
Herb subgroup 19A.......................................... 0.05
* * * * *
Nut, tree, group 14........................................ 0.05
* * * * *
Pear....................................................... 0.5
* * * * *
Spinach.................................................... 0.2
* * * * *
Tomato..................................................... 0.15
* * * * *
------------------------------------------------------------------------
\1\ There are no U.S. registrations as of April 30, 2003.
(2) A tolerance of 0.05 ppm is established for residues of the
insecticide bifenthrin, (2-methyl[1,1'-biphenyl]-3-yl)methyl-3-(2-
chloro-3,3,3-trifluoro-1-propenyl)-2,2-dimethylcyclopropane-
carboxylate, as follows:
(i) In or on all food/feed items (other than those covered by a
higher tolerance as a result of use on growing crops) in food/feed
handling establishments.
(ii) The insecticide may be present as a residue from application
of bifenthrin in food handling establishments, including food service,
manufacturing and processing establishments, such as restaurants,
cafeterias, supermarkets, bakeries, breweries, dairies, meat
slaughtering and packing plants, and canneries, feed handling
establishments including feed manufacturing and processing
establishments, in accordance with the following prescribed conditions:
(A) Application shall be limited to general surface and spot and/or
crack and crevice treatment in food/feed handling establishments where
food/feed and food/feed products are held, processed, prepared and
served. General surface application may be used only when the facility
is not in operation provided exposed food/feed has been covered or
removed from the area being treated. Spot and/or crack and crevice
application may be used while the facility is in operation provided
exposed food/feed is covered or removed from the area being treated
prior to application. Spray concentration shall be limited to a maximum
of 0.06 percent active ingredient. Contamination of food/feed or food/
feed contact surfaces shall be avoided.
(B) To assure safe use of the insecticide, its label and labeling
shall conform to that registered with the U.S. Environmental Protection
Agency and shall be used in accordance with such label and labeling.
* * * * *
[FR Doc. 03-10400 Filed 4-29-03; 8:45 am]
BILLING CODE 6560-50-S