Bifenthrin. Sept 27, 2001. Pesticide tolerances for Emergency Exemptions for residues in or on Sweet Potato at 0.05 ppm. Final Rule. Federal Register.

FLUORIDE ACTION NETWORK PESTICIDE PROJECT

Bifenthrin. September 27, 2001. Pesticide Tolerances for Emergency Exemptions for residues in or on Sweet Potato at 0.05 ppm. Final Rule. Federal Register.

http://www.epa.gov/fedrgstr/EPA-PEST/2001/September/Day-27/p24199.htm

[Federal Register: September 27, 2001 (Volume 66, Number 188)]
[Rules and Regulations]
[Page 49300-49308]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27se01-24]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-301169; FRL-6801-5]
RIN 2070-AB78

Bifenthrin; Pesticide Tolerances for Emergency Exemptions

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

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SUMMARY: This regulation establishes a time-limited tolerance for
residues of bifenthrin in or on sweet potato. This action is in
response to EPA's granting of an emergency exemption under section 18
of the Federal Insecticide, Fungicide, and Rodenticide Act authorizing
use of the pesticide on sweet potato. This regulation establishes a
maximum permissible level for residues of bifenthrin in this food
commodity. The tolerance will expire and is revoked on December 31,
2003.

DATES: This regulation is effective September 27, 2001. Objections and
requests for hearings, identified by docket control number OPP-301169,
must be received by EPA on or before November 26, 2001.

ADDRESSES: Written objections and hearing requests may be submitted by
mail, in person, or by courier. Please follow the detailed instructions
for each method as provided in Unit VII. of the SUPPLEMENTARY
INFORMATION: To ensure proper receipt by EPA, your objections and
hearing requests must identify docket control number OPP-301169 in the
subject line on the first page of your response.

FOR FURTHER INFORMATION CONTACT: By mail: Shaja R. Brothers,
Registration Division (7505C), Office of Pesticide Programs,
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460; telephone number: (703) 308-3194; and e-mail
address:brothers.shaja@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

You may be potentially affected by this action if you are an
agricultural producer, food manufacturer, or pesticide manufacturer.
Potentially affected categories and entities may include, but are not
limited to:

------------------------------------------------------------------------
Examples of
Categories NAICS codes potentially
affected entities
------------------------------------------------------------------------
Industry 111 Crop production
.............................. 112 Animal production
311 Food manufacturing
.............................. 32532 Pesticide
manufacturing
------------------------------------------------------------------------

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 the table could also be
affected. The North American Industrial Classification System (NAICS)
codes have been provided to assist you and others in determining
whether or not this actionmight apply to certain entities. If you have
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 Additional Information, Including Copies of This
Document and Other Related Documents?

1. Electronically. You may obtain electronic copies of this
document, and certain other related documents that might be available
electronically, from the EPA Internet Home Page at http://www.epa.gov/.
To access this document, on the Home Page select ``Laws and
Regulations,'' ``Regulations and Proposed Rules,'' and then look up the
entry for this document under the ``Federal Register--Environmental
Documents.'' You can also go directly to 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.
2. In person. The Agency has established an official record for
this action under docket control number OPP-301169. The official record
consists of the documents specifically referenced in this action, and
other information related to this action, including any information
claimed as Confidential Business Information (CBI). This official
record includes the documents that are physically located in the
docket, as well as the documents that are referenced in those
documents. The public version of the official record does not include
any information claimed as CBI. The public version of the official
record, which includes printed, paper versions of any electronic
comments submitted during an applicable comment period is available for
inspection in the Public Information and Records Integrity Branch
(PIRIB), Rm. 119, Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA,
from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal
holidays. The PIRIB telephone number is (703) 305-5805.

II. Background and Statutory Findings

EPA, on its own initiative, in accordance with sections 408(e) and
408 (l)(6) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21
U.S.C. 346a, is establishing a tolerance 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 sweet potato at 0.05 part
per million (ppm). This tolerance will expire and is revoked on
December 31, 2003. EPA will publish a document in the Federal Register
to remove the revoked tolerance from the Code of Federal Regulations.
Section 408(l)(6) of the FFDCA requires EPA to establish a time-
limited tolerance or exemption from the requirement for a tolerance for
pesticide chemical residues in food that will result from the use of a
pesticide under an emergency exemption granted by EPA under section 18
of FIFRA. Such tolerances can be established without providing notice
or period for public comment. EPA does not intend for its actions on
section 18 related tolerances to set binding precedents for the
application of section 408 and the new safety standard to other
tolerances and exemptions. Section 408(e) of the FFDCA allows EPA to
establish a tolerance or an exemption from the requirement of a
tolerance on its own initiative, i.e., without having received any
petition from an outside party.
Section 408(b)(2)(A)(i) of the FFDCA allows EPA to establish a
tolerance (the legal limit for a pesticide chemical residue in or on a
food) only if EPA determines that the tolerance is ``safe.'' Section
408(b)(2)(A)(ii) defines ``safe'' to mean that ``there is a reasonable
certainty that no harm will result from aggregate exposure to the
pesticide chemical residue, including all anticipated dietary exposures
and all other exposures for which there is reliable information.''This
includes exposure through drinking water and in residential settings,
but does not include occupational exposure. Section 408(b)(2)(C)
requires EPA to give special consideration to exposure of infants and
children to the pesticide chemical residue in establishing a tolerance
and to ``ensure that there is a reasonable certainty that no harm will
result to infants and children from aggregate exposure to the pesticide
chemical residue. . . .''
Section 18 of the Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA) authorizes EPA to exempt any Federal or State agency from
any provision of FIFRA, if EPA determines that ``emergency conditions
exist which require such exemption.'' This provision was not amended by
the Food Quality Protection Act (FQPA). EPA has established regulations
governing such emergency exemptions in 40 CFR part 166.

[[Page 49302]]

III. Emergency Exemption for Bifenthrin on Sweet potato and FFDCA
Tolerances

EPA has authorized under FIFRA section 18 the use of bifenthrin on
sweet potato for control of the sweet potato weevil and beetle in the
states of Mississippi and Louisiana. After having reviewed the
submission, EPA concurs that emergency conditions exist for these
States.
As part of its assessment of this emergency exemption, EPA assessed
the potential risks presented by residues of bifenthrin in or on sweet
potato. In doing so, EPA considered the safety standard in FFDCA
section 408(b)(2), and EPA decided that the necessary tolerance under
FFDCA section 408(l)(6) would be consistent with the safety standard
and with FIFRA section 18. Consistent with the need to move quickly on
the emergency exemption in order to address an urgent non-routine
situation and to ensure that the resulting food is safe and lawful, EPA
is issuing this tolerance without notice and opportunity for public
comment as provided in section 408(l)(6). Although this tolerance will
expire and is revoked on December 31, 2003, under FFDCA section
408(l)(5), residues of the pesticide not in excess of the amounts
specified in the tolerance remaining in or on sweet potato after that
date will not be unlawful, provided the pesticide is applied in a
manner that was lawful under FIFRA, and the residues do not exceed a
level that was authorized by this tolerance at the time of that
application. EPA will take action to revoke this tolerance earlier if
any experience with, scientific data on, or other relevant information
on this pesticide indicate that the residues are not safe.
Because this tolerance is being approved under emergency
conditions, EPA has not made any decisions about whether bifenthrin
meets EPA's registration requirements for use on sweet potato or
whether a permanent tolerance for this use would be appropriate. Under
these circumstances, EPA does not believe that this tolerance serves as
a basis for registration of bifenthrin by a State for special local
needs under FIFRA section 24(c). Nor does this tolerance serve as the
basis for any States other than Mississippi and Louisiana to use this
pesticide on this crop under section 18 of FIFRA without following all
provisions of EPA's regulations implementing section 18 as identified
in 40 CFR part 166. For additional information regarding the emergency
exemption for bifenthrin, contact the Agency's Registration Division at
the address provided under FOR FURTHER INFORMATION CONTACT.

IV. Aggregate Risk Assessment and Determination of Safety

EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 and a complete description of
the risk assessment process, see the final rule on Bifenthrin Pesticide
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).
Consistent with section 408(b)(2)(D), 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 a time-limited tolerance for
residues of bifenthrin in or on sweet potato at 0.05 ppm. EPA's
assessment of the dietary exposures and risks associated with
establishing the tolerance follows.

A. 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 endpoint. 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.
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 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 safety factor.
For non-dietary risk assessments (other than cancer) the UF is used
to determine the level of concern (LOC). For example, when 100 is the
appropriate UF (10x to account for interspecies differences and 10x for
intraspecies differences) the LOC is 100. To estimate risk, a ratio of
the NOAEL to exposures (margin of exposure (MOE) = NOAEL/exposure) is
calculated and compared to the LOC.
The linear default risk methodology (Q*) is the primary method
currently used by the Agency to quantify carcinogenic risk. The Q*
approach assumes that any amount of exposure will lead to some degree
of cancer risk. A Q* is calculated and used to estimate risk which
represents a probability of occurrence of additional cancer cases
(e.g., risk is expressed as 1 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 (MOE _cancer = point of
departure/exposures) is calculated. A summary of the toxicological
endpoints for bifenthrin used for human risk assessment is shown in the
following Table 1.

[[Page 49303]]

Table 1. -- 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 Oral NOAEL = 1.0 mg/kg/ FQPA SF = 1x Developmental toxicity,
including infants and children day aPAD = acute RfD....... Rats - tremors in dams
UF = 100............... FQPA SF = 0.01 mg/kg/ during & post dosing
Acute RfD = 0.01 mg/kg/ day.
day.
----------------------------------------------------------------------------------------------------------------
Chronic dietary all populations Oral dietary exposure FQPA SF = 1x Chronic oral, dogs -
NOAEL= 1.5 mg/kg/day... cPAD = chronic RfD..... tremors in both sexes
UF = 100............... FQPA SF = 0.015 mg/kg/
Chronic RfD = 0.015 mg/ day.
kg/day.
----------------------------------------------------------------------------------------------------------------
Short-term dermal (1 to 7 days) Dermal exposure LOC for MOE = 100 Developmental toxicity,
(Occupational/Residential)........... Oral NOAEL= 1.0 mg/kg/ (Residential) Rats - tremors in dams
day. during & post dosing
(dermal absorption rate
= 25%.
----------------------------------------------------------------------------------------------------------------
Intermediate-term dermal (1 week to Dermal exposure LOC for MOE = 100 Developmental toxicity,
several months) Oral NOAEL= 1.0 mg/kg/ (Residential) Rats - tremors in dams
(Occupational/Residential)........... day. during & post dosing
(Dermal absorption rate
= 25%.
----------------------------------------------------------------------------------------------------------------
Chronic dermal (several months to Inhalation exposure LOC for MOE = 100 Chronic oral, dogs -
lifetime) Oral NOAEL = 1.5 mg/kg/ (Residential) tremors in both sexes
(Occupational/Residential)........... day.
(Use inhalation
absorption rate= 25%).
----------------------------------------------------------------------------------------------------------------
All time periods: Inhalation Inhalation exposure LOC for MOE = 100 Development toxicity,
(Occupational/Residential)........... Oral NOAEL = 1.0 mg/kg/ (Residential) Rats - tremors in dams
day. Risk assessment should during & post dosing
(Inhalation absorption be inclusive of (No appropriate
rate = 100%). dietary &inhalation inhalation studies
exposure components. available)
----------------------------------------------------------------------------------------------------------------
Cancer Dietary/Dermal/ Use reference dose Carcinogenicity,
Inhalation (RfD) approach Mice - urinary bladder
Exposure group C Long-term consumption tumors in male mice
carcinogen. of bifenthrin are
adequately addressed
by the chronic
exposure analysis.
----------------------------------------------------------------------------------------------------------------
* The reference to the FQPA safety factor refers to any additional safety factor retained due to concerns unique
to the FQPA.

B. 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
the following raw agricultural commodities: Globe artichoke; brassica,
head and stem subgroup excluding cabbage; cabbage; caneberry subgroup;
corn; cottonseed; eggplant; grape; head lettuce; pea and bean succulent
shelled subgroup; pepper (bell and non-bell); rapeseed; strawberries;
cucurbit vegetable crop group; and edible podded legume vegetable
subgroup. Egg; fat, meat by product, and meat of cattle, goats, hogs,
horses, poultry and sheep; and milk fat tolerances have also been
established for bifenthrin. Time-limited tolerances under section 18
currently exists for grapes and peanuts (nutmeats) and are set to
expire on December 31, 2001. Additional tolerances also include citrus
(dried pulp, oil, whole fruit) and potato, and are set to expire on
December 31, 2003. 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)
analysis evaluated the individual food consumption as reported by
respondents in the USDA (1994-1996) 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 Monte Carlo analysis
(Tier 3) was used. PCT (% crop treated) and anticipated residues were
used for registered crops, and 100% crop treated was used for all other
unregistered crops.
ii. Chronic exposure. In conducting this chronic dietary risk
assessment the DEEM analysis evaluated the individual food consumption
as reported by respondents in the USDA (1994-1996) nationwide CSFII and
accumulated exposure to the chemical for each commodity. The following
assumptions were made for the chronic exposure

[[Page 49304]]

assessments: In conducting this new DEEM analysis for the chronic
dietary (food only) risk assessment, the agency 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.
100% crop treated was assumed for all crops except hops (43%) and
cottonseed-oil and cottonseed-meal (4%).
iii. Cancer. Bifenthrin has been classified as a Group C chemical
(possible human carcinogen) based upon urinary bladder tumors in mice.
No Q* was assigned because the RfD approach was recommended for cancer
risk assessment. Based on this recommendation, a quantitative dietary
cancer risk assessment was not performed since dietary risk concerns
due to long-term consumption of bifenthrin are adequately addressed by
the chronic exposure analysis using the RfD.
iv. Anticipated residue and percent crop treated information.
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 this
tolerance.
Section 408(b)(2)(F) 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), EPA may require registrants to submit data on
PCT.
The Agency used PCT information as follows.43% hops, and 4%
cottonseed-oil and cotton-meal
The Agency believes that the three conditions listed above have
been met. With respect to condition 1, PCT estimates are derived from
Federal and private market survey data, which are reliable and have a
valid basis. EPA uses a weighted average PCT for chronic dietary
exposure estimates. This weighted average PCT figure is derived by
averaging State-level data for a period of up to 10 years, and
weighting for the more robust and recent data. A weighted average of
the PCT reasonably represents a person's dietary exposure over a
lifetime, and is unlikely to underestimate exposure to an individual
because of the fact that pesticide use patterns (both regionally and
nationally) tend to change continuously over time, such that an
individual is unlikely to be exposed to more than the average PCT over
a lifetime. For acute dietary exposure estimates, EPA uses an estimated
maximum PCT. The exposure estimates resulting from this approach
reasonably represent the highest levels to which an individual could be
exposed, and are unlikely to under estimate an individual's acute
dietary exposure. The Agency is reasonably certain that the percentage
of the food treated is not likely to be an underestimation. As to
conditions 2 and 3, regional consumption information and consumption
information for significant subpopulations is taken into account
through EPA's computer-based model for evaluating the exposure of
significant subpopulations including several regional groups. Use of
this consumption information in EPA's risk assessment process ensures
that EPA's exposure estimate does not understate exposure for any
significant subpopulation group and allows the Agency to be reasonably
certain that no regional population is exposed to residue levels higher
than those estimated by the Agency. Other than the data available
through national food consumption surveys, EPA does not have available
information on the regional consumption of food to which bifenthrin may
be applied in a particular area.
2. Dietary exposure from drinking water. The Agency lacks
sufficient monitoring exposure data to complete a comprehensive dietary
exposure analysis and risk assessment for 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 Generic Estimated Environmental Concentration
(GENEEC) or the Pesticide Root Zone/Exposure Analysis Modeling System
(PRZM/EXAMS) to estimate pesticide concentrations in surface water and
SCI-GROW, which predicts pesticide concentrations in ground water. In
general, EPA will use GENEEC (a tier 1 model) before using PRZM/EXAMS
(a tier 2 model) for a screening-level assessment for surface water.
The GENEEC model is a subset of the PRZM/EXAMS model that uses a
specific high-end runoff scenario for pesticides. GENEEC incorporates a
farm pond scenario, while PRZM/EXAMS incorporate an index reservoir
environment in place of the previous pond scenario. 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 below.
Based on the GENEEC and SCI-GROW models, EECs for bifenthrin acute
and chronic exposure for surface water are estimated to be 0.1 parts
per billion (ppb) and 0.032 (average 56-day) ppb, respectively. The
ground water

[[Page 49305]]

screening concentration is 0.006 ppb. These values represent upper-
bound estimates of the concentrations that might be found in surface
water and ground water from the highest application rate for
bifenthrin, 0.5 lb ai/A, used on cotton.
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: Lawn for flea infestation control, and
residential flowable insecticide/miticide. Under current EPA
guidelines, these uses do not present a chronic exposure scenario, but
may constitute a short- and/or intermediate-term exposure scenario. A
residential exposure assessment for the lawn care uses of bifenthrin
was conducted in conjunction with the ``Risk Assessment for Extension
of Tolerances for Synthetic Pyrethroids.''
4. Cumulative exposure to substances with a 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.''
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).

C. Safety Factor for Infants and Children

1. In general. 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 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 margin of exposure
(MOE) analysis or through using uncertainty (safety) factors in
calculating a dose level that poses no appreciable risk to humans.
2. Developmental toxicity studies. In a rabbit developmental
toxicity study, there were no developmental effects observed in the
fetuses exposed to bifenthrin. The maternal NOAEL was 2.67 milligram/
kilogram/day (mg/kg/day) based on head and forelimb twitching at the
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 5/23 (22%) of the
litters affected (5/141 fetuses since each litter only had one affected
fetus) 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, background incidence of distended ureter
averaged 11% with a maximum incidence of 90%.
3. Reproductive toxicity study. In the rat reproduction study,
parental toxicity occurred as decreased body weight and tremors 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).
4. Prenatal and postnatal sensitivity--i. Prenatal. 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.
ii. Postnatal. Based on the absence of pup toxicity up to dose
levels which produced toxicity in the parental animals, there is no
evidence of special postnatal sensitivity to infants and children in
the rat reproduction study.
5. Conclusion. There is a complete toxicity data base for
bifenthrin and exposure data are complete or are estimated based on
data that reasonably accounts for potential exposures. EPA determined
that the 10x safety factor to protect infants and children should be
removed. Based on the above, EPA concludes that reliable data support
use of the standard 100-fold uncertainty factor, and that an additional
uncertainty factor is not needed to protect the safety of infants and
children.

D. Aggregate Risks and Determination of Safety

To estimate total aggregate exposure to a pesticide from food,
drinking water, and residential uses, the Agency calculates DWLOCs
which are used as a point of comparison against the model estimates of
a pesticide's concentration in water (EECs). DWLOC values are not
regulatory standards for drinking water. DWLOCs are theoretical upper
limits on a pesticide's concentration in drinking water in light of
total aggregate exposure to a pesticide in food and residential uses.
In calculating a DWLOC, the Agency determines how much of the
acceptable exposure (i.e., the PAD) is available for exposure through
drinking water [e.g., allowable chronic water exposure (mg/kg/day) =
cPAD - (average food + chronic non-dietary, non-occupational
exposure)]. This allowable exposure through drinking water is used to
calculate a DWLOC.
A DWLOC will vary depending on the toxic endpoint, drinking water
consumption, and body weights. Default body weights and consumption
values as used by the US EPA Office of Water are used to calculate
DWLOCs: 2Liters/70 kilograms (adult male), 2L/60 kg (adult female), and
1L/10 kg (child). Default body weights and drinking water consumption
values vary on an individual basis. This variation will be taken into
account in more refined screening-level and quantitative drinking water
exposure assessments. Different populations will have different DWLOCs.
Generally, a DWLOC is calculated for each type of risk assessment used:
Acute, short-term, intermediate-term, chronic, and cancer.
When EECs for surface water and ground water are less than the
calculated DWLOCs, OPP concludes with reasonable certainty that
exposures to bifenthrin in drinking water (when considered along with
other sources of exposure for which OPP has reliable data) would not
result in unacceptable levels of aggregate human health risk at this
time. Because OPP 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

[[Page 49306]]

future, OPP will reassess the potential impacts of bifenthrin on
drinking water as a part of the aggregate risk assessment process.
1. Acute risk. Using the exposure assumptions discussed in this
unit for acute exposure, the acute dietary exposure from food to
bifenthrin will occupy 60% of the aPAD for the U.S. population, 40% of
the aPAD for females 13 years and older, 75% of the aPAD for all
infants <1 year old and 99.7% of the aPAD for children (1-6 years old).
In addition, despite the potential for acute dietary exposure to
bifenthrin in drinking water, after calculating DWLOCs and comparing
them to conservative model EECs of bifenthrin in surface and ground
water, EPA does not expect the aggregate exposure to exceed 100% of the
aPAD, as shown in the following Table 2.

Table 2. -- Aggregate Risk Assessment for Acute Exposure to Bifenthrin
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup aPAD (mg/ %aPAD Water EEC Water EEC Acute DWLOC
kg) (Food) (ppb) (ppb) (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. Population (48 contiguous states) 0.01 60 0.1 0.006 140
----------------------------------------------------------------------------------------------------------------
Female 13+ yr 0.01 40 0.1 0.006 180
----------------------------------------------------------------------------------------------------------------
Children (1-6 yr) 0.01 99.7 0.1 0.006 0.30
----------------------------------------------------------------------------------------------------------------

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 3% of the cPAD for the U.S.
population, 3% of the cPAD for females 13 years and older and 8.2% of
the cPAD for children (1-6 years old). Based the use pattern, chronic
residential exposure to residues of bifenthrin is not expected. In
addition, despite the potential for chronic dietary exposure to
bifenthrin in drinking water, after calculating DWLOCs and comparing
them to conservative model EECs of bifenthrin in surface and ground
water, EPA does not expect the aggregate exposure to exceed 100% of the
cPAD, as shown in the following Table 3.

Table 3. -- Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Bifenthrin
----------------------------------------------------------------------------------------------------------------
Surface Ground
Population Subgroup cPAD mg/kg/ %cPAD Water EEC Water EEC Chronic
day (Food) (ppb) (ppb) DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------
U.S. Population (48 continguous states) 0.015 3 0.032 0.006 530
----------------------------------------------------------------------------------------------------------------
Females 13+ 0.015 3 0.032 0.006 450
----------------------------------------------------------------------------------------------------------------
Children (1-6 yrs old) 0.015 8.2 0.032 0.006 140
----------------------------------------------------------------------------------------------------------------

3. Short- and intermediate-term risk. Short- and 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
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 940 for adults, 350 for children
(1-6 yrs old), and 470 for infants < 1 yr old. 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
water 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
the following Table 4.

Table 4. -- Aggregate Risk Assessment for Short- and Intermediate-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 940 100 0.032 0.006 320
----------------------------------------------------------------------------------------------------------------
Children (1-6yrs) 350 100 0.032 0.006 270
----------------------------------------------------------------------------------------------------------------
Infants <1yr 470 100 0.032 0.006 71
----------------------------------------------------------------------------------------------------------------

4. Aggregate cancer risk for U.S. population. Bifenthrin has been
classified as a Group C chemical (possible human carcinogen) based upon
urinary bladder tumors in mice. No Q* was assigned because the RfD
approach was recommended for cancer risk assessment. Based on this
recommendation, a quantitative dietary

[[Page 49307]]

cancer risk assessment was not performed since dietary risk concerns
due to long-term consumption of bifenthrin are adequately addressed by
the chronic exposure analysis using the RfD. Based on a comparison of
the calculated DWLOCs and the estimated exposure to bifenthrin in
drinking water, the agency does not expect the chronic aggregate
exposure to exceed 100% of the cPAD (cRfD) for adults. Thus, EPA
concludes with reasonable certainty that the carcinogenic risk is
within acceptable limits.
5. 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.

V. Other Considerations

Adequate enforcement methodology is available to enforce the
tolerance expression. The method may be requested from: Calvin Furlow,
PRRIB, IRSD (7502C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW, Washington, DC 20460;
telephone number: (703) 305-5229; e-mail address:
furlow.calvin@epa.gov.

VI. Conclusion

Therefore, the tolerance is established for residues of bifenthrin,
[(2-methyl [1,1'-biphenyl]
-3-yl) methyl-3-(2-chloro-3,3,3-trifluoro-1-
propenyl)-2,2-dimethylcyclopropanecarboxylate], in or on sweet potato
at 0.05 ppm.

VII. Objections and Hearing Requests

Under section 408(g) of the FFDCA, as amended by the FQPA, any
person may file an objection to any aspect of this regulation and may
also request a hearing on those objections. The EPA procedural
regulations which govern the submission of objections and requests for
hearings appear in 40 CFR part 178. Although the procedures in those
regulations require some modification to reflect the amendments made to
the FFDCA by the FQPA of 1996, EPA will continue to use those
procedures, with appropriate adjustments, until the necessary
modifications can be made. The new section 408(g) 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), as was provided in the old FFDCA sections 408 and 409.
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 control number OPP-301169 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 November
26, 2001.
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 (1900),
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460. You may also deliver your request to the Office
of the Hearing Clerk in Rm. C400, Waterside Mall, 401 M St., SW.,
Washington, DC 20460. The Office of the Hearing Clerk is open from 8
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The
telephone number for the Office of the Hearing Clerk is (202) 260-4865.
2. Tolerance fee payment. If you file an objection or request a
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must
mail the fee to: EPA Headquarters Accounting Operations Branch, Office
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please
identify the fee submission by labeling it ``Tolerance Petition Fees.''
EPA is authorized to waive any fee requirement ``when in the
judgement of the Administrator such a waiver or refund is equitable and
not contrary to the purpose of this subsection.'' For additional
information regarding the waiver of these fees, you may contact James
Tompkins by phone at (703) 305-5697, by e-mail at tompkins.jim@epa.gov,
or by mailing a request for information to Mr. Tompkins at Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
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.
3. Copies for the Docket. In addition to filing an objection or
hearing request with the Hearing Clerk as described in Unit VII.A., you
should also send a copy of your request to the PIRIB for its inclusion
in the official record that is described in Unit I.B.2.Mail your
copies, identified by the docket control number OPP-301169, 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.
In person or by courier, bring a copy to the location of the PIRIB
described in Unit I.B.2. 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).

VIII. Regulatory Assessment Requirements

This final rule establishes a time-limited tolerance under FFDCA
section 408. The Office of Management and Budget (OMB) has exempted
these types of actions from review under Executive

[[Page 49308]]

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 prior consultation as specified by Executive Order
13084, entitled Consultation and Coordination with Indian Tribal
Governments (63 FR 27655, May 19, 1998); 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 or
any Agency action under Executive Order 13045, entitled Protection of
Children from Environmental Health Risks and Safety Risks (62 FR 19885,
April 23, 1997). This action does not involve any technical standards
that would require Agency consideration of voluntary consensus
standards pursuant to section 12(d) of the National Technology Transfer
and Advancement Act of 1995 (NTTAA), Public Law 104-113, section 12(d)
(15 U.S.C. 272 note). Since tolerances and exemptions that are
established on the basis of a FIFRA section 18 exemption under FFDCA
section 408, 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 FFDCA section 408(n)(4).

IX. 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 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: September 11, 2001.

Peter Caulkins,
Acting Director, Registration Division, Office of Pesticide Programs.

Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

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

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

2. Section 180.442 is amended by alphabetically adding the
following commodity to the table in paragraph (a) to read as follows:

Sec. 180.442 Bifenthrin; tolerances for residues.

(a)* * *

------------------------------------------------------------------------
Expiration/
Commodity Parts per million Revocation Date
------------------------------------------------------------------------
* * * * *
Sweet potato 0.05 12/31/03
* * * * *
------------------------------------------------------------------------

* * * * *

[FR Doc. 01-24199 Filed 9-26-01; 8:45 am]
BILLING CODE 6560-50-S

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Last Updated: Sep 27 15:50:55 2001
URL: http://www.epa.gov/fedrgstr/EPA-PEST/2001/September/Day-27/p24199.htm