Bifenthrin; Pesticide Tolerance
[Federal Register: June 30, 1999 (Volume 64, Number 125)]
[Rules and Regulations]
[Page 35051-35058]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30jn99-28]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300888; FRL-6089-9]
RIN 2070-AB78
Bifenthrin; Pesticide Tolerance
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes 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-
dimethylcyclopropanecarboxylate, in or on the food commodities: cabbage
at 4.0 part per million (ppm); the cucurbit vegetable crop group (Crop
Group 9) at 0.4 ppm; edible- podded legume vegetable subgroup (Crop
Subgroup 6A) at 0.6 ppm; eggplant at 0.05 ppm; globe artichoke at 1.0
ppm; head and stem Brassica subgroup (Crop Subgroup 5A), except
cabbage, at 0.6 ppm; rapeseed at 0.05 ppm, succulent shelled pea and
bean subgroup (Crop Subgroup 6B) at 0.05 ppm; sweet corn kernel plus
cob with husk removed at 0.05 ppm; and corn forage at 3.0 ppm. The
Interregional Research Project (IR-4) and FMC Corporation requested
these tolerances under the Federal Food, Drug, and Cosmetic Act, as
amended by the Food Quality Protection Act of 1996.
DATES: This regulation is effective June 30, 1999. Objections and
requests for hearings must be received by EPA on or before August 30,
1999.
ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [OPP-300888], must be submitted to: Hearing
Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M St.,
SW., Washington, DC 20460. Fees accompanying objections and hearing
requests shall be labeled ``Tolerance Petition Fees'' and forwarded to:
EPA Headquarters Accounting Operations Branch, OPP (Tolerance Fees),
P.O. Box 360277M, Pittsburgh, PA 15251. A copy of any objections and
hearing requests filed with the Hearing Clerk identified by the docket
control number, [OPP-300888], must also be submitted to: Public
Information and Records Integrity Branch, Information Resources and
Services Division (7502C), Office of Pesticide Programs, Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460. In person,
bring a copy of objections and hearing requests to Rm. 119, Crystal
Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA.
A copy of objections and hearing requests filed with the Hearing
Clerk may be submitted electronically by sending electronic mail (e-
mail) to: opp-docket@epa.gov. Copies of objections and hearing requests
must be submitted as an ASCII file avoiding the use of special
characters and any form of encryption. Copies of objections and hearing
requests will also be accepted on disks in WordPerfect 5.1/6.1 file
format or ASCII file format. All copies of objections and hearing
requests in electronic form must be identified by the docket control
number [OPP-300888]. No Confidential Business Information (CBI) should
be submitted through e-mail. Electronic copies of objections and
hearing requests on this rule may be filed online at many Federal
Depository Libraries.
FOR FURTHER INFORMATION CONTACT: By mail: Hoyt Jamerson, Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460. Office
location, telephone number, and e-mail address: Rm. 272, Crystal Mall
#2, 1921 Jefferson Davis Hwy., Arlington, VA, (703) 308-9368, e-mail:
jamerson.hoyt@epa.gov.
SUPPLEMENTARY INFORMATION: In the Federal Register of October 7, 1998
(63 FR 53902) (FRL-6026-3), and May 19, 1999 (64 FR 27262) (FRL-6079-
8), EPA issued notices pursuant to section 408 of the Federal Food,
Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a as amended by the Food
Quality Protection Act of 1996 (FQPA) (Public Law 104-170) announcing
the filing of pesticide petitions for tolerances by the Interregional
Research Project Number 4 (IR-4), New Jersey Agricultural Experimental
Station, P.O. Box 231, Rutgers University, New Brunswick, NJ, and FMC
Corporation, 1753 Market Street, Philadelphia, PA 19103. 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.
The petitions requested that 40 CFR 180.442 be amended by
establishing tolerances for residues of the insecticide bifenthrin, in
or on various food commodities, as follows:
1. IR-4 petition 6E4629 proposes the establishment of a tolerance
for globe artichoke at 1.0 ppm. IR-4 first proposed the tolerance for
the commodity ``artichokes,'' but the petition was amended to specify
the food commodity as ``globe artichoke.''
[[Page 35052]]
2. IR-4 petition 6E4760 proposes the establishment of a tolerance
for the cucurbit vegetable crop group at 0.4 ppm.
3. IR-4 petition 8E4993 proposes the establishment of a tolerance
for the edible-podded legume vegetable subgroup at 0.6 ppm. The initial
proposal was for a tolerance for the edible- podded legume vegetable
group at 0.2 ppm. Based on EPA's review of the field residue data
submitted by IR-4, the petition was revised by the petitioner to
propose the tolerance at 0.6 ppm.
4. IR-4 petition 8E5009 proposes the establishment of a tolerance
for eggplant at 0.05 ppm.
5. IR-4 petition 9E5084 proposes the establishment of a tolerance
for rapeseed (including canola and crambe seed) at 0.05 ppm.
6. IR-4 petition 9E5064 proposes the establishment of a tolerance
for succulent shelled pea and bean subgroup at 0.05 ppm.
7. IR-4 petition 9E5069 proposes the establishment of a tolerance
for the head and stem Brassica subgroup, except cabbage, at 0.6 ppm;
and cabbage at 4.0 ppm.
8. FMC Corporation petition 8F5014 proposes the establishment of a
tolerance for sweet corn grain at 0.05 ppm and corn forage at 3.0 ppm.
The petition was amended by changing the commodity term ``sweet corn
grain'' to read ``sweet corn kernel plus cob with husk removed.''
I. Background and Statutory Findings
Section 408(b)(2)(A)(i) of the FFDCA allows EPA to establish a
tolerance (the legal limit for a pesticide chemical residue in or on a
food) only if EPA determines that the tolerance is ``safe.'' Section
408(b)(2)(A)(ii) defines ``safe'' to mean that ``there is a reasonable
certainty that no harm will result from aggregate exposure to the
pesticide chemical residue, including all anticipated dietary exposures
and all other exposures for which there is reliable information.'' This
includes exposure through drinking water and in residential settings,
but does not include occupational exposure. Section 408(b)(2)(C)
requires EPA to give special consideration to exposure of infants and
children to the pesticide chemical residue in establishing a tolerance
and to ``ensure that there is a reasonable certainty that no harm will
result to infants and children from aggregate exposure to the pesticide
chemical residue....''
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 and a complete description of
the risk assessment process, see the final rule on Bifenthrin Pesticide
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).
II. Aggregate Risk Assessment and Determination of Safety
Consistent with section 408(b)(2)(D), EPA has reviewed the
available scientific data and other relevant information in support of
this action. EPA has sufficient data to assess the hazards of
bifenthrin and to make a determination on aggregate exposure,
consistent with section 408(b)(2), for tolerances for residues of
bifenthrin on cabbage at 4.0 ppm; the cucurbit vegetable crop group at
0.4 ppm; edible-podded legume vegetable subgroup at 0.6 ppm; eggplant
at 0.05 ppm; globe artichoke at 1.0 ppm; head and stem Brassica
subgroup, except cabbage, at 0.6 ppm; rapeseed at 0.05 ppm; succulent
shelled pea and bean subgroup at 0.05 ppm; sweet corn kernel plus cob
with husk removed at 0.05 ppm; and corn forage at 3.0 ppm. EPA's
assessment of the dietary exposures and risks associated with
establishing the 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. The nature of the toxic effects caused by bifenthrin are
discussed in this unit.
1. Genotoxicity. The following genotoxicity tests conducted with
bifenthrin all yielded negative results including: gene mutation in
Salmonella (Ames); chromosomal aberrations in Chinese hamster ovary and
rat bone marrow cells; HGPRT locus mutation in mouse lymphoma cells;
and unscheduled DNA synthesis in rat hepatocytes. Bifenthrin tested
positive in a mouse lymphoma forward mutation assay, with and without
metabolic activation.
2. Developmental toxicity. In the rabbit developmental toxicity
study, there were no developmental effects observed in the fetuses
exposed to bifenthrin. The maternal no observed adverse effect level
(NOAEL) was 2.67 milligrams (mg)/kilogram (kg)/day based on head and
forelimb twitching at the lowest observed adverse effect level (LOAEL)
of 4 mg/kg/day. In the rat developmental study, the maternal NOAEL was
1 mg/kg/day, based on tremors at the LOAEL of 2 mg/kg/day. The
developmental (pup) NOAEL was also 1 mg/kg/day, based upon increased
incidence of hydroureter at the LOAEL of 2 mg/kg/day. There were 5 of
23 (22 percent) litters affected with each litter having only one
affected pup in the 2 mg/kg/day group, compared with zero in the
control, 1 and 0.5 mg/kg/day groups. According to recent historical
data (1992-1994) for this strain of rat, incidence of distended ureter
averaged 11 percent with a maximum incidence of 90 percent.
3. Reproductive toxicity. In the rat reproduction study, parental
toxicity occurred as decreased body weight at 5.0 mg/kg/day with a
NOAEL of 3.0 mg/kg/day. There were no developmental (pup) or
reproductive effects up to 5.0 mg/kg/day (highest dose tested)(HDT).
4. Chronic toxicity/carcinogenicity. In a 1-year chronic/
carcinogenicity study dogs were fed diets containing 0, 0.75, 1.5, 3,
or 5 mg/kg/day. No mortality occurred during the study and there were
no treatment-related effects on body weight, food consumption, organ
weights, and gross or microscopic pathology. In addition, there were no
treatment-related ophthalmological changes. Tremors were noted in all
males and females at 5 mg/kg/day during weeks 15-29 and in 1 of 4 males
and 2 of 4 females at 3 mg/kg/day during weeks 16-23. A significant
increase in platelets was noted at 52 weeks in males fed 5 mg/kg/day .
Serum sodium levels were significantly increased in males at 3 and 5
mg/kg/day and serum chloride was increased in males fed 5 mg/kg/day.
The LOAEL for this study is 3 mg/kg/day based on the increased
incidence of tremors in both sexes. The NOAEL is 1.5 mg/kg/day.
5. Chronic/carcinogenicity study. In this study mice were fed doses
of 0, 50, 200, 500, or 600 ppm (0, 2.5, 10, 25, or 30 mg/kg/day) in the
diet for 87 weeks (males) or 92 weeks (females). The chronic LOAEL was
established at 10 mg/kg/day based on the incidence of tremors in both
sexes. The chronic NOAEL is established at 2.5 mg/kg/day. Carcinogenic
potential was evidenced by a statistically significant increased trend
for hemangiopericytomas in the urinary bladders of males, 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.
6. Chronic/carcinogenicity study. In this study rats were fed diets
containing 0, 12, 50, 100, or 200 ppm (0, 0.6, 2.5,
[[Page 35053]]
5, or 10 mg/kg/day). The chronic LOAEL is 5 mg/kg/day based on the
increased incidence of tremors in both sexes and possible increases in
organ-to-body weight ratios in males, and the chronic NOAEL is
established at 2.5 mg/kg/day. Under the conditions of this study, there
was no evidence of carcinogenic potential.
7. Animal metabolism. Metabolism studies in rats demonstrated that
distribution patterns and excretion rates in multiple oral dose studies
are similar to single-dose studies. There was an accumulation of
unchanged compound in fat upon chronic administration with slow
elimination. Otherwise, bifenthrin was rapidly metabolized and
excreted. Unchanged bifenthrin is the major residue component of
toxicological concern in meat and milk.
B. Toxicological Endpoints
1. Acute dietary toxicity. The acute reference doses (RfD) for
dietary exposure is established at 0.01 mg/kg/day. The acute RfD is
based on a developmental toxicity study in the rat with a maternal
NOAEL of 1.0 mg/kg of body weight/day and an uncertainty factor (UF) of
100. The FQPA Safety Factor for the protection of infants and children
was reduced to 1x. (See Unit II.E.iv. in the preamble of this document
for discussion of pre- and post-natal sensitivity to bifenthrin.) The
acute population adjusted dose (acute PAD) is determined by dividing
the acute RFD by the FQPA factor: acute PAD = 0.01 / 1 = 0.01 mg/kg /
day. Since the FQPA Safety Factor is 1X, the acute RfD is identical to
the acute PAD. This acute PAD applies to all population subgroups.
2. Short- and intermediate-term residential dermal toxicity. For
short- and intermediate- term dermal endpoints, EPA selected the
maternal NOAEL of 1.0 mg/kg/day from the oral developmental toxicity
study in rats (same study as for acute dietary exposure). The dermal
absorption rate is 25% and a MOE of 100 was selected, which includes
FQPA considerations.
3. Chronic residential dermal exposure. For the chronic dermal
endpoint, EPA selected the NOAEL of 1.5 mg/kg/day from the 1-year oral
study in dogs (same study as for chronic dietary exposure). The dermal
absorption rate is 25% and a MOE of 100 was selected, which includes
FQPA considerations.
4. Chronic dietary toxicity. EPA has established the chronic RfD
for bifenthrin at 0.015 mg/kg/day. This RfD is based on a 1-year oral
feeding study in dogs with a NOAEL of 1.5 mg/kg/day and an uncertainty
factor (UF) of 100. The FQPA Safety Factor for the protection of
infants and children was reduced to 1x. The chronic population adjusted
dose (chronic PAD) is determined by dividing the chronic RfD by the
FQPA factor. Since the FQPA safety factor is 1X, the chronic RfD is
identical to the chronic PAD. This chronic PAD applies to all
population subgroups.
5. Carcinogenicity. Bifenthrin has been classified as a Group C
Carcinogen (a possible human carcinogen). A cancer risk assessment
using the RfD approach is required.
C. Exposures and Risks
1. From food and feed uses. Tolerances have been established (40
CFR 180.442) for the residues of bifenthrin, in or on a variety of food
commodities. Tolerances are established on plant commodities ranging
from 0.05 ppm on field corn grain to 10 ppm on dried hops. Tolerances
are also established on animal commodities including meat, meat
byproducts and fat of cattle, goats, hogs, horses, poultry, sheep, and
milk and eggs. Risk assessments were conducted by EPA to assess dietary
exposures from bifenthrin as follows:
The acute dietary (food only) risk assessment was conducted by
Novigen Science, Inc. In this acute analysis, Monte Carlo analysis
(Tier 3) was used. For those foods identified by EPA as single-serving
commodities, Monte Carlo simulation is based on iterative sampling from
individual residue values from field trial data reflecting maximum
application rates and minimum preharvest intervals. For those
considered to be blended or processed, mean field trial residues were
calculated, substituting those samples for which residues were reported
at or below the limit of detection (LOD) with one-half of the LOD. It
was assumed that 100% crop treated for all pending registrations:
citrus, snap beans, peas, lima beans, canola, sweet corn, cucurbits,
eggplant, and Brassica vegetable. Secondary residues for meat and milk
were derived from the total dietary burden and tissue- to- feed ratio,
using the highest ratio for meat, and the average ratio for milk.
This analysis evaluates individual food consumption as reported by
respondents in the USDA Continuing Surveys of Food Intake by
Individuals conducted in 1989 through 1992. The model accumulates
exposure to the chemical for each commodity and expresses risk as a
function of exposure to residues in food. This is a highly refined
assessment since percent of crop treated was used for registered crops
and anticipated residues for all crops.
In conducting this DEEM analysis for chronic food risk assessment,
Novigen used anticipated residue values which were determined from
field trial data conducted at maximum label conditions of maximum
application rates and minimum preharvest intervals. Mean anticipated
residue values were calculated, substituting one-half of the LOD for
those samples for which residues were reported below the LOD. It was
assumed that 100% crop treated for all crops except hops at 43%,
cottonseed-oil and cottonseed-meal at 4%. Secondary residues for meat
and milk were derived from the total dietary burden and tissue- to-
feed ratio, using the average ratio for meat and milk. The analysis
evaluates individual food consumption as reported by respondents in the
USDA Continuing Surveys of Food Intake by Individuals conducted in 1989
through 1992.
Section 408(b)(2)(E) 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), 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
these tolerances.
Section 408(b)(2)(F) states that the Agency may use data on the
actual percent of food treated (PCT) for assessing chronic dietary risk
only if the Agency can make the following findings: 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; that the exposure estimate does not underestimate exposure for
any significant subpopulation group; and 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 percent of crop treated as required by the section 408(b)(2)(F), EPA
may
[[Page 35054]]
require registrants to submit data on PCT.
The Agency believes that the three conditions, discussed in section
408 (b)(2)(F) in this unit concerning the Agency's responsibilities in
assessing chronic dietary risk findings, have been met. The PCT
estimates are derived from Federal and private market survey data,
which are reliable and have a valid basis. A range of estimates are
supplied and the upper end of this range is assumed for the exposure
assessment. By using this upper end estimate of the PCT, the Agency is
reasonably certain that the percentage of the food treated is not
likely to be underestimated. The regional consumption information and
consumption information for significant subpopulations is taken into
account through EPA's computer-based model for evaluating the exposure
of significant subpopulations including several regional groups. Use of
this consumption information in EPA's risk assessment process ensures
that EPA's exposure estimate does not understate exposure for any
significant subpopulation group and allows the Agency to be reasonably
certain that no regional population is exposed to residue levels higher
than those estimated by the Agency. Other than the data available
through national food consumption surveys, EPA does not have available
information on the regional consumption of food to which bifenthrin may
be applied in a particular area.
i. Acute exposure and risk (food). Acute dietary risk assessments
are performed for a food-use pesticide if a toxicological study has
indicated the possibility of an effect of concern occurring as a result
of a 1-day or single exposure. The percentages of the acute PAD
utilized at the 99.9th percentile of exposure are 53% for the U.S.
population, 63% for infants (<1 year), 58% for non-nursing infants (< 1
year) and 96% for children (1-6 years old), the most highly exposed
population subgroup. An acute dietary exposure (food plus water) of
100% or less of the acute PAD is needed to protect the safety of all
population subgroups.
ii. Chronic exposure and risk (food). The most highly exposed
population subgroup (children 1-6 years) will utilize 6.7% of the
chronic PAD. The exposure for the U.S. population is 2.4% of the
chronic PAD. A chronic dietary exposure (food plus water) of 100% or
less of the chronic PAD is needed to protect the safety of all
population subgroups.
2. From drinking water. A Drinking Water Level of Comparison
(DWLOC) is a theoretical upper limit on a pesticide's concentration in
drinking water in light of total aggregate exposure to a pesticide in
food, drinking water, and through residential uses. A DWLOC will vary
depending on the toxic endpoint, drinking water consumption, and body
weights. Different populations will have different DWLOCs. The Agency
uses DWLOCs internally in the risk assessment process as a surrogate
measure of potential exposure associated with pesticide exposure
through drinking water. In the absence of monitoring data for
pesticides, it is used as a point of comparison against conservative
model estimates of a pesticide's concentration in water. DWLOC values
are not regulatory standards for drinking water. They do have an
indirect regulatory impact through aggregate exposure and risk
assessments. The estimated acute and chronic drinking water
concentrations were generated with the PRZMI/EXAMS model using the
highest application rate of 0.5 pounds/acre, which is registered for
use on cotton.
i. Acute exposure and risk (water). For purposes of this acute risk
assessment, the estimated acute maximum concentration for bifenthrin in
surface and ground waters is 0.10 <greek-m>g (micrograms)/L (liter),
which was used for comparison to the back- calculated DWLOCs for the
acute endpoint. The DWLOCs for various population categories are 165
<greek-m>g/L for the U.S. population, 200 <greek-m>g/L for females 13
years and older, and 4 <greek-m>g/L for children 1 to 6 years. Acute
exposure to bifenthrin in drinking water is below the calculated
drinking water levels of concern.
ii. Chronic exposure and risk (water). For purposes of chronic risk
assessment, the estimated chronic maximum concentration for bifenthrin
in surface and ground waters is 0.032 <greek-m>g/L, which was used for
comparison to the back-calculated human health DWLOCs from the chronic
(non-cancer) endpoint. These DWLOCs for various population categories
are 530 <greek-m>g/L for the U.S. population, 450 <greek-m>g/L for
females 13 years and older, and 140 <greek-m>g/L for children 1 to 6
years. Chronic exposure to bifenthrin in drinking water is below the
calculated drinking water levels of concern. iii. Short- and
intermediate-term exposure and risk (water). For purposes of short- and
intermediate-term risk assessment, the estimated chronic maximum
concentration for bifenthrin in surface and ground waters is 0.032
<greek-m>g/L, which was used for comparison to the back-calculated
human health DWLOCs from the short- and intermediate-term endpoints.
The DWLOCs for various population categories are 290 <greek-m>g/L for
the U.S. population, 250 <greek-m>g/L for females 13 years and older,
and 77 <greek-m>g/L for children 1 to 6 years. Short- and intermediate-
term exposure to bifenthrin in drinking water is below the calculated
drinking water levels of concern.
3. From non-dietary exposure. Bifenthrin is currently registered
for use on the residential non-food sites outdoor lawn and garden,
inside households and termiticide use. These registered uses constitute
short- and/or intermediate-term, and chronic exposure.
i. Chronic exposure and risk (residential). Although the registered
termiticide use of bifenthrin constitutes a chronic exposure scenario,
the exposure from this termiticide use is negligible considering the
application technique of the termiticide use (buried underground) and
the fact that vapor pressure of bifenthrin is extremely low (1.8 x 10
<SUP>-7</SUP> torr). .
ii. Short- and intermediate-term exposure and risk (residential).
This risk assessment is based on post-application to treated lawns
(turf use), a worst case scenario estimate of residential exposure. An
assessment of applicator exposure was not included since the registered
products are primarily limited to commercial use and, therefore,
applied by professional lawn care operators. Inhalation, dermal and
oral non-dietary routes of exposure were evaluated by this short- and
intermediate-term risk assessment. For adults, the routes of exposure
from these registered residential uses include dermal and inhalation,
and for infants and children, the routes of exposure include dermal,
inhalation, and oral (nondietary). The MOEs for residential exposures
are 1600 for adults, 610 for children (1 to 6 years), and 600 for
infants (<1 year). These MOE's are well above the acceptable short-term
aggregate MOE of 100.
4. Cumulative exposure to substances with common mechanism of
toxicity. Section 408(b)(2)(D)(v) requires that, when considering
whether to establish, modify, or revoke a tolerance, the Agency
consider ``available information'' concerning the cumulative effects of
a particular pesticide's residues and ``other substances that have a
common mechanism of toxicity.''
Bifenthrin is a member of a class of chemicals commonly referred to
as ``Synthetic Pyrethroids.'' Other members of this class include
cyfluthrin, cypermethrin, lambda- cyhalothrin, zeta-cypermethrin,
deltamethrin, esfenvalerate,
[[Page 35055]]
fenpropathrin, tefluthrin and tralomethrin.
EPA does not have, at this time, available data to determine
whether bifenthrin has a common mechanism of toxicity with other
substances or how to include this pesticide in a cumulative risk
assessment. Unlike other pesticides for which EPA has followed a
cumulative risk approach based on a common mechanism of toxicity,
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 final rule
for Bifenthrin Pesticide Tolerances (62 FR 62961, November 26, 1997).
5. Endocrine disrupter effects. EPA is required to develop a
screening program to determine whether certain substances (including
all pesticides and inerts) ``may have an effect in humans that is
similar to an effect produced by a naturally occurring estrogen, or
such other endocrine effect...'' The Agency is currently working with
interested stakeholders, including other government agencies, public
interest groups, industry and research scientists in developing a
screening and testing program and a priority setting scheme to
implement this program. Congress has allowed 3 years from the passage
of FQPA (August 3, 1999) to implement this program. At that time, EPA
may require further testing of this active ingredient and end use
products for endocrine disrupter effects.
D. Aggregate Risks and Determination of Safety for U.S. Population
1. Acute risk (food + water). Using the Monte Carlo analysis, it
is estimated that the acute exposure to bifenthrin from food for the
U.S. population subgroup will utilize 53% of the acute PAD. Children 1
to 6 years are the most highly exposed population subgroup. (See
discussion in Unit II.E.) An acute dietary exposure (food plus water)
of 100% or less of the acute PAD is needed to protect the safety of all
population subgroups. Despite the potential for exposure to bifenthrin
in drinking water, EPA does not expect the aggregate exposure to exceed
100% of the acute PAD for adults, infants and children. The estimated
maximum concentration of bifenthrin in surface and ground water for
acute exposure is below the DWLOC.
2. Chronic risk (food + water + residential). Using the exposure
assumptions described in this unit, EPA has concluded that aggregate
exposure to bifenthrin from food will utilize 2.4% of the chronic PAD
for the U.S. population. The major identifiable subgroup with the
highest aggregate exposure is children 1 to 6 years. [See discussion in
Unit II.E. in the preamble of this document] EPA generally has no
concern for exposures below 100% of the chronic PAD because the chronic
PAD represents the level at or below which daily aggregate dietary
exposure over a lifetime will not pose appreciable risks to human
health. Despite the potential for exposure to bifenthrin in drinking
water, EPA does not expect the aggregate exposure to exceed 100% of the
chronic PAD, the estimated maximum concentration of bifenthrin in
surface and ground water for chronic exposure is very small compared to
the DWLOC. Although the registered termiticide use of bifenthrin
constitutes a chronic exposure scenario, the exposure from this
termiticide use is negligible considering the application technique of
the termiticide use (buried underground) and the fact that vapor
pressure of bifenthrin is extremely low (1.8 x 10 <SUP>-7</SUP> torr).
3. Short- and intermediate-term risk. Short- and intermediate-term
aggregate exposure takes into account chronic dietary food and water
(considered to be a background exposure level) plus indoor and outdoor
residential exposure. In the case of bifenthrin, the registered
residential use sites include outdoor lawn/gardens, inside households
and termiticide. These uses constitute a short- and intermediate-term
exposure scenario. The short- and intermediate-term aggregate risk
assessment for bifenthrin includes inhalation, dermal, oral non-
dietary, chronic food, and water exposure routes. The acceptable MOEs
for short- and intermediate-term exposures are all at 100. For adults,
the routes of exposure from these registered, residential uses include
dermal and inhalation, and for infants and children, the routes of
exposure include dermal, inhalation, and oral (nondietary). The MOEs
for food (excluding water) and residential exposures is 1200 for
adults, 430 for children 1 to 6 years, and 500 for infants less than 1
year. These MOEs are well above the acceptable short-term aggregate MOE
of 100.
Since residue values in drinking water are not available, the
DWLOCs have to be back- calculated. The short- and intermediate-term
DWLOCs are 290 <greek-m>g/L for adult males, 250 <greek-m>g/L for adult
females, 77 <greek-m>g/L for children 1 to 6 years, and 77 <greek-m>g/L
for infants (less than 1 year old). The estimated maximum concentration
of bifenthrin in surface and ground water for chronic exposure 0.032
<greek-m>g/L is very small compared to the DWLOCs.
4. Aggregate cancer risk for U.S. population. Bifenthrin has been
classified as a group C carcinogen, using the RfD approach. Based on
the recommendation that the RfD approach be used, a quantitative (q*)
dietary cancer risk assessment was not performed. Dietary risk concerns
due to long-term consumption of bifenthrin are adequately addressed by
the DEEM chronic exposure analysis using the chronic PAD (RfD). For the
U.S. population, only 2.4% of the chronic PAD (RfD) is occupied by
chronic food exposure. As stated previously, based on a comparison of
the calculated DWLOCs and the estimated exposure to bifenthrin in
drinking water (0.032 g/L), EPA does not expect the aggregate exposure
to exceed 100% of the chronic PAD (RfD) for adults.
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
from aggregate exposure to bifenthrin residues.
E. Aggregate Risks and Determination of Safety for Infants and Children
1. Safety factor for infants and children -- i. In general. In
assessing the potential for additional sensitivity of infants and
children to residues of bifenthrin, EPA considered data from
developmental toxicity studies in the rat and rabbit and a 2-generation
reproduction study in the rat. The developmental toxicity studies are
designed to evaluate adverse effects on the developing organism
resulting from maternal pesticide exposure gestation. Reproduction
studies provide information relating to effects from exposure to the
pesticide on the reproductive capability of mating animals and data on
systemic toxicity.
FFDCA section 408 provides that EPA shall apply an additional
tenfold margin of safety for infants and children in the case of
threshold effects to account for pre-and post-natal toxicity and the
completeness of the database unless EPA determines that a different
margin of safety will be safe for infants and children. Margins of
safety are incorporated into EPA risk assessments either directly
through use of a margin of exposure (MOE) analysis or through using
uncertainty (safety) factors in calculating a dose level that poses no
appreciable risk to humans. EPA believes that reliable data support
using the standard uncertainty factor (usually
[[Page 35056]]
100 for combined inter- and intra-species variability) and not the
additional tenfold MOE/uncertainty factor when EPA has a complete data
base under existing guidelines and when the severity of the effect in
infants or children or the potency or unusual toxic properties of a
compound do not raise concerns regarding the adequacy of the standard
MOE/safety factor.
ii. Developmental toxicity studies. In the rabbit developmental
study, there were no developmental effects observed in the fetuses
exposed to bifenthrin. The maternal NOEL was 2.67 mg/kg/day based on
head and forelimb twitching at the LOAEL of 4 mg/kg/day. In the rat
developmental study, the maternal NOEL was 1 mg/kg/day, based on
tremors at the LOAEL of 2 mg/kg/day. The developmental (pup) NOEL was
also 1 mg/kg/day, based upon increased incidence of hydroureter at the
LOAEL 2 mg/kg/day. There were 5 of 23 (22%) litters affected with each
litter having only one affected pup in the in the 2 mg/kg/day group,
compared with zero in the control, 1 and 0.5 mg/kg/day groups.
According to recent historical data (1992-1994) for this strain of rat,
incidence of distended ureter averaged 11% with a maximum incidence of
90%.
iii. Reproductive toxicity study. In the rat reproduction study,
parental toxicity occurred as decreased bwt at 5.0 mg/kg/day with a
NOEL of 3.0 mg/kg/day. There were no developmental (pup) or
reproductive effects up to 5.0 mg/kg/day (HDT).
iv. Pre- and post-natal sensitivity -- a. Pre-natal. Since there
was not a dose-related finding of hydroureter in the rat developmental
study and in the presence of similar incidences in the recent
historical control data, the marginal finding of hydroureter in rat
fetuses at 2 mg/kg/day (in the presence of maternal toxicity) is not
considered a significant developmental finding. Nor does it provide
sufficient evidence of a special dietary risk (either acute or chronic)
for infants and children which would require an additional safety
factor.
b. Post-natal. Based on the absence of pup toxicity up to dose
levels which produced toxicity in the parental animals, there is no
evidence of special post-natal sensitivity to infants and children in
the rat reproduction study.
v. Conclusion. There is a complete toxicity database for bifenthrin
and exposure data is complete or is estimated based on data that
reasonably accounts for potential exposures. Based on the completeness
of the toxicity data and pre- and post-natal toxicity of bifenthrin, no
additional safety factor is needed to protect infants and children.
2. Acute risk. (Food + Water.) The percentages of the acute PAD
utilized at the 99.9th percentile of exposure are 63% for infants (less
than 1 year) and 96% for children (1 to 6 years), the most highly
exposed population subgroup. An acute dietary exposure (food plus
water) of 100% or less of the acute PAD is needed to protect the safety
of all population subgroups. Despite the potential for exposure to
bifenthrin in drinking water, EPA does not expect the aggregate
exposure to exceed 100% of the acute PAD for infants and children. The
estimated maximum concentration of bifenthrin in surface and ground
water for acute exposure is below the DWLOC.
3. Chronic risk. Using the exposure assumptions described in this
unit, EPA has concluded that aggregate exposure to bifenthrin from food
will utilize 6.7% of the chronic PAD (RfD) for children (1 to 6 years).
EPA generally has no concern for exposures below 100% of the RfD
because the RfD represents the level at or below which daily aggregate
dietary exposure over a lifetime will not pose appreciable risks to
human health. Despite the potential for exposure to bifenthrin in
drinking water and from non-dietary, non-occupational exposure, EPA
does not expect the aggregate exposure to exceed 100% of the RfD.
4. Short- or intermediate-term risk. The MOEs for food (excluding
water) and residential exposures is 430 for children (1 to 6 years),
and 500 for infants (less than 1 year). These MOEs are well above the
acceptable short-term aggregate MOE of 100. The short- and
intermediate-term DWLOCs are 77 <greek-m>g/L for children (1 to 6
years), and 77 <greek-m>g/L for infants (less than 1 year). The
estimated maximum concentration of bifenthrin in surface and ground
water for chronic exposure (<greek-m>g/L) is very small compared to the
DWLOCs.
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to infants and children from aggregate exposure to bifenthrin residues.
III. Other Considerations
A. Metabolism In Plants and Animals
The metabolism of bifenthrin in plants and animals is adequately
understood. Studies conducted to delineate the metabolism of radio-
labeled bifenthrin in various crops and animals show similar results.
The residue of concern is the parent compound only.
B. Analytical Enforcement Methodology
Adequate enforcement methods are available for determination of
the regulated bifenthrin residue in plants and animals. Residues of
bifenthrin are recoverable under Protocols D and E of the FDA
Multiresidue Methods.
C. Magnitude of Residues
An adequate number of residue field trials reflecting the proposed
use rates were submitted to EPA to demonstrate that tolerances for
cabbage at 4.0 ppm; the cucurbit vegetable crop group at 0.4 ppm;
edible-podded legume vegetable subgroup at 0.6 ppm; eggplant at 0.05
ppm; globe artichoke at 1.0 ppm; head and stem Brassica subgroup,
except cabbage, at 0.6 ppm; rapeseed at 0.05 ppm, succulent shelled pea
and bean subgroup at 0.05 ppm; sweet corn at 0.05 ppm; and corn forage
at 0.6 ppm will not be exceeded when bifenthrin products labeled for
these uses are used as directed.
D. International Residue Limits
There are no Codex Maximum Residue Levels (MRL's) for these
commodities.
E. Rotational Crop Restrictions
Crops with established U.S. tolerances may be rotated at any time.
Leafy vegetable and root crops may be rotated 30 days following the
final application. All other crops may be rotated seven months
following the final application.
IV. Conclusion
Therefore, the tolerance is established for residues of bifenthrin
in cabbage at 4.0 part per million (ppm); the cucurbit vegetable crop
group (Crop Group 9) at 0.4 ppm; edible- podded legume vegetable
subgroup (Crop Subgroup 6A) at 0.6 ppm; eggplant at 0.05 ppm; globe
artichoke at 1.0 ppm; head and stem Brassica subgroup (Crop Subgroup
5A), except cabbage, at 0.6 ppm; rapeseed at 0.05 ppm, succulent
shelled pea and bean subgroup (Crop Subgroup 6B) at 0.05 ppm; sweet
corn kernel plus cob with husk removed at 0.05 ppm; and corn forage at
3.0 ppm.
V. Objections and Hearing Requests
The new FFDCA section 408(g) provides essentially the same process
for persons to ``object'' to a tolerance regulation as was provided in
the old section 408 and in section 409. However, the period for filing
objections is 60 days, rather than 30 days. EPA currently has
procedural regulations which govern the submission of objections and
hearing requests. These regulations will require some modification to
reflect the new law.
[[Page 35057]]
However, until those modifications can be made, EPA will continue to
use those procedural regulations with appropriate adjustments to
reflect the new law.
Any person may, by August 30, 1999, file written objections to any
aspect of this regulation and may also request a hearing on those
objections. Objections and hearing requests must be filed with the
Hearing Clerk, at the address given under the ``ADDRESSES'' section (40
CFR 178.20). A copy of the objections and/or hearing requests filed
with the Hearing Clerk should be submitted to the OPP docket for this
regulation. The objections submitted must specify the provisions of the
regulation deemed objectionable and the grounds for the objections (40
CFR 178.25). Each objection must be accompanied by the fee prescribed
by 40 CFR 180.33(I). 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 tolerance objection fee waivers,
contact James Tompkins, Registration Division (7505C), Office of
Pesticide Programs, Environmental Protection Agency, 401 M St., SW.,
Washington, DC 20460. Office location, telephone number, and e-mail
address: Rm. 239, Crystal Mall #2, 1921 Jefferson Davis Hwy.,
Arlington, VA, (703) 305-5697, tompkins.jim@epa.gov. Requests for
waiver of tolerance objection fees should be sent to James Hollins,
Information Resources and Services Division (7502C), Office of
Pesticide Programs, Environmental Protection Agency, 401 M St., SW.,
Washington, DC 20460.
If a hearing is requested, the objections must include a statement
of the factual issues on which a hearing is requested, the requestor's
contentions on such issues, and a summary of any evidence relied upon
by the requestor (40 CFR 178.27). A request for a hearing will be
granted if the Administrator determines that the material submitted
shows the following: There is genuine and substantial issue of fact;
there is a reasonable possibility that available evidence identified by
the requestor would, if established, resolve one or more of such issues
in favor of the requestor, taking into account uncontested claims or
facts to the contrary; and resolution of the factual issues in the
manner sought by the requestor would be adequate to justify the action
requested (40 CFR 178.32). Information submitted in connection with an
objection or hearing request may be claimed confidential by marking any
part or all of that information as CBI. Information so marked will not
be disclosed except in accordance with procedures set forth in 40 CFR
part 2. A copy of the information that does not contain CBI must be
submitted for inclusion in the public record. Information not marked
confidential may be disclosed publicly by EPA without prior notice.
VI. Public Record and Electronic Submissions
EPA has established a record for this regulation under docket
control number [OPP-300888] (including any comments and data submitted
electronically). A public version of this record, including printed,
paper versions of electronic comments, which does not include any
information claimed as CBI, is available for inspection from 8:30 a.m.
to 4 p.m., Monday through Friday, excluding legal holidays. The public
record is located in Room 119 of the Public Information and Records
Integrity Branch, Information Resources and Services Division (7502C),
Office of Pesticide Programs, Environmental Protection Agency, Crystal
Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA.
Objections and hearing requests may be sent by e-mail directly to
EPA at:
opp-docket@epa.gov.
E-mailed objections and hearing requests must be submitted as an
ASCII file avoiding the use of special characters and any form of
encryption.
The official record for this regulation, as well as the public
version, as described in this unit will be kept in paper form.
Accordingly, EPA will transfer any copies of objections and hearing
requests received electronically into printed, paper form as they are
received and will place the paper copies in the official record which
will also include all comments submitted directly in writing. The
official record is the paper record maintained at the Virginia address
in ``ADDRESSES'' at the beginning of this document.
VII. Regulatory Assessment Requirements
A. Certain Acts and Executive Orders
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). 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 prior consultation as specficed by Executive Order
12875, entitled Enhancing the Intergovernmental Partnership (58 FR
58093, October 28, 1993), or special considerations as required by
Executive Order 12898, entitled Federal Actions to Address
Environmental Justice in Minority Populations and Low-Income
Populations (59 FR 7629, February 16, 1994), or require OMB review in
accordance with Executive Order 13045, entitled Protection of Children
from Environmental Health Risks and Safety Risks (62 FR 19885, April
23, 1997).
In addition, since tolerances and exemptions that are established
on the basis of a petition under FFDCA section 408(d), such as the
tolerance/exemption in this final rule, do not require the issuance of
a proposed rule, the requirements of the Regulatory Flexibility Act
(RFA) (5 U.S.C. 601 et seq.) do not apply. Nevertheless, the Agency
previously assessed whether establishing tolerances, exemptions from
tolerances, raising tolerance levels or expanding exemptions might
adversely impact small entities and concluded, as a generic matter,
that there is no adverse economic impact. The factual basis for the
Agency's generic certification for tolerance actions published on May
4, 1981 (46 FR 24950), and was provided to the Chief Counsel for
Advocacy of the Small Business Administration.
B. Executive Order 12875
Under Executive Order 12875, entitled Enhancing the
Intergovernmental Partnership (58 FR 58093, October 28, 1993), EPA may
not issue a regulation that is not required by statute and that creates
a mandate upon a State, local or tribal government, unless the Federal
government provides the funds necessary to pay the direct compliance
costs incurred by those governments. If the mandate is unfunded, EPA
must provide to OMB a description of the extent of EPA's prior
consultation with representatives of affected State, local, and tribal
governments, the nature of their concerns, copies of any written
communications from the governments, and a statement supporting the
need to issue the regulation. In addition, Executive Order 12875
requires EPA to develop an effective process permitting elected
officials and other representatives of State, local, and tribal
governments ``to provide meaningful
[[Page 35058]]
and timely input in the development of regulatory proposals containing
significant unfunded mandates.''
Today's rule does not create an unfunded Federal mandate on State,
local, or tribal governments. The rule does not impose any enforceable
duties on these entities. Accordingly, the requirements of section 1(a)
of Executive Order 12875 do not apply to this rule.
C. Executive Order 13084
Under Executive Order 13084, entitled Consultation and Coordination
with Indian Tribal Governments (63 FR 27655, May 19, 1998), EPA may not
issue a regulation that is not required by statute, that significantly
or uniquely affects the communities of Indian tribal governments, and
that imposes substantial direct compliance costs on those communities,
unless the Federal government provides the funds necessary to pay the
direct compliance costs incurred by the tribal governments. If the
mandate is unfunded, EPA must provide OMB, in a separately identified
section of the preamble to the rule, a description of the extent of
EPA's prior consultation with representatives of affected tribal
governments, a summary of the nature of their concerns, and a statement
supporting the need to issue the regulation. In addition, Executive
Order 13084 requires EPA to develop an effective process permitting
elected officials and other representatives of Indian tribal
governments ``to provide meaningful and timely input in the development
of regulatory policies on matters that significantly or uniquely affect
their communities.''
Today's rule does not significantly or uniquely affect the
communities of Indian tribal governments. This action does not involve
or impose any requirements that affect Indian tribes. Accordingly, the
requirements of section 3(b) of Executive Order 13084 do not apply to
this rule.
VIII. Submission to Congress and the Comptroller General
The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the Agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and the Comptroller General of the United
States. EPA will submit a report containing this rule and other
required information to the U.S. Senate, the U.S. House of
Representatives and the Comptroller General of the United States prior
to publication of the rule in the Federal Register. This rule is not a
``major rule'' as defined by 5 U.S.C. 804(2).
List of Subjects in 40 CFR Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.
Dated: June 23, 1999.
James Jones,
Director, Registration Division, Office of Pesticide Programs.
Therefore, 40 CFR chapter I is amended as follows:
PART 180--[AMENDED]
1. The authority citation for part 180 continues to read as
follows:
Authority: 21 U.S.C. 346a and 371.
2. In Sec. 180.442, by amending paragraph (a) by revising the
introductory text and the tolerance level for ``corn forage'' and by
alphabetically adding the following entries to the table:
Sec. 180.442 Bifenthrin; tolerances for residues.
(a) General. Tolerances are 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-dimethylcyclopropanecarboxylate
in or on the following food commodities:
------------------------------------------------------------------------
Commodity Parts per million
------------------------------------------------------------------------
Artichoke, globe.......................... 1.0
Brassica, head and stem, subgroup, 0.6
excluding cabbage.
Cabbage................................... 4.0
* * * * * * *
Corn, forage.............................. 3.0
* * * * * * *
Corn, sweet, kernel plus cob with husk 0.05
removed.
Eggplant.................................. 0.05
* * * * * * *
Pea and bean, succulent shelled, subgroup. 0.05
* * * * * * *
Rapeseed.................................. 0.05
* * * * * * *
Vegetable, cucurbit, crop group........... 0.4
Vegetable, legume, edible podded, subgroup 0.6
------------------------------------------------------------------------
* * * * *
[FR Doc. 99-16575 Filed 6-29-99; 8:45 am]
BILLING CODE 6560-50-F
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