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Bifenthrin - Pesticide Tolerances for Emergency Exemptions 9/00

[Federal Register: September 27, 2000 (Volume 65, Number 188)]
[Rules and Regulations]
[Page 57972-57980]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27se00-12]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-301047; FRL-6744-4]
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 potato. This action is in response to
EPA's granting of emergency exemptions under section 18 of the Federal
Insecticide, Fungicide, and Rodenticide Act authorizing use of the
pesticide on potatoes. 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, 2002.

DATES: This regulation is effective September 27, 2000. Objections and
requests for hearings, identified by docket control number OPP-301047,
must be received by EPA on or before November 27, 2000.

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-301047 in the
subject line on the first page of your response.

FOR FURTHER INFORMATION CONTACT: By mail: Andrea Conrath, Registration

Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460;
telephone number:(703) 308-9356; and e-mail
address:beard.andrea@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

[[Page 57973]]

assist you and others in determining whether or not this action might
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 theFederal Register listings
at http://www.epa.gov/fedrgstr/.
    2. In person. The Agency has established an official record for
this action under docket control number OPP-301047. 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 (l)(6)
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a, is
establishing a tolerance for residues of the pesticide bifenthrin, in
or on potato at 0.05 part per million (ppm). This tolerance will expire
and is revoked on December 31, 2002. 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(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.

III. Emergency Exemption for Bifenthrin on Potatoes and FFDCA
Tolerances

    Two-spotted spider mites have recently emerged as a major potato
pest in the Pacific Northwest. This pest can reach damaging numbers as
a result of spray programs to control other pests, which disrupts
natural biological predators that would normally keep the spider mite
populations in check. Damaging levels of spider mites have occurred in
Washington and Oregon, and the registered alternatives do not provide
adequate control. They are more slow acting, and lack the residual
control of bifenthrin, and do not control heavier mite populations
quickly enough to prevent economic damage. Significant economic losses
are expected for the Pacific Northwest potato growers if this pest
cannot be adequately controlled. Bifenthrin has been shown to be
effective at controlling spider mites. EPA has authorized under FIFRA
section 18 the use of bifenthrin on potatoes for control of spider
mites in Washington and Oregon. 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
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, 2002, under FFDCA section
408(l)(5), residues of the pesticide not in excess of the amounts
specified in the tolerance remaining in or on 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 potatoes 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 State other than Washington and Oregon 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

[[Page 57974]]

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 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 observed adverse effects level 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 intra species 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 (MOEcancer = point of
departure/exposures) is calculated. A summary of the toxicological
endpoints for Bifentherin used for human risk assessment is shown in
the following Table 1:

          Table 1.--Summary of Toxicological 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                 effect
----------------------------------------------------------------------------------------------------------------
Acute dietary (All populations)        Oral NOAEL = 1.0 mg/kg/  Acute population         Developmental toxicity,
                                        day UF=100 Acute RfD:    adjusted dose (aPAD)     rats--tremors in dams
                                        0.01 mg/kg/day           aPAD =acute RfD = 0.01   during & post dosing
                                                                 mg/kg/day FQPA SF = 1X
Chronic dietary (All populations)      Oral dietary exposure    Chronic population       Chronic oral, dogs--
                                        NOAEL =1.5 mg/kg/day     adjusted dose (cPAD)     tremors in both sexes
                                        UF = 100 Chronic RfD:    cPAD = chronic RfD =
                                        0.015 mg/kg/day          0.015 mg/kg/day FQPA
                                                                 SF = 1X
Short term dermal (1-7 days)           Dermal exposure Oral     MOE = 100 FQPA SF = 1X   Developmental toxicity,
 (Residential)                          NOAEL =1.0 mg/kg/day                              rats - tremors in dams
                                        (Use dermal absorption                            during & post dosing
                                        rate = 25%)
Intermediate term dermal (one week to  Dermal exposure oral     MOE = 100 FQPA SF = 1X   Developmental toxicity,
 several months) (Residential)          NOAEL =1.0 mg/kg/day                              rats - tremors in dams
                                        (use dermal absorption                            during & post dosing
                                        rate=25%)
Chronic dermal (several month to       Dermal exposure oral      MOE=100 FQPA SF = 1X    Chronic oral, dogs -
 lifetime) (Residential)                NOAEL =1.5 mg/kg/day                              tremors in both sexes
                                        (use dermal absorption
                                        rate = 25%)
All time periods: inhalation           Inhalation exposure      MOE=100 risk assessment  Developmental toxicity,
 (Residential)                          Oral NOAEL = 1.0 mg/kg/  should be inclusive of   rats - tremors in dams
                                        day (use inhalation      dietary & inhalation     during & post dosing
                                        absorption rate =        exposure components      (No appropriate
                                        100%)                    FQPA SF = 1X             inhalation studies
                                                                                          available)
Cancer                                 Dietary/dermal/          use RfD approach FQPA     Carcinogenicity, mice
                                        inhalation exposure      SF = 1X                   urinary bladder
                                        group C carcinogen                                tumors in male mice
----------------------------------------------------------------------------------------------------------------
* The reference to the FQPA Safety Factor refers to any additional safety factor retained due to concerns unique
  to the FQPA. In this case, the FQPA Safety Factor for enhanced sensitivity of infants and children was reduced
  to 1X (explained further below under (C)).

[[Page 57975]]

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 a
variety of raw agricultural commodities, (RAC) ranging from 0.05 ppm
for corn grain to 10 ppm for dried hops. Tolerances are also
established on animal commodities ranging from 0.05 ppm on eggs to 1.0
ppm in milk fat. 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\DM\)
analysis evaluated the individual food consumption as reported by
respondents in the USDA [insert 1989-1992 or 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: In this acute
analysis, probabilistic Monte Carlo analysis (Tier 3) was used. For
those foods identified by EPA as single-serving commodities, the 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 foods considered to be blended
or processed, mean field trial residues were calculated. For those
samples which contained residues at or below the limit of detection
(LOD), 1/2 of the LOD was used. It was assumed that 100% of the
following crops were treated with bifenthrin: artichoke, bananas,
brassica vegetable, caneberry, canola, citrus, cucurbits, eggplants,
garden peas, grape, head lettuce, lima beans, peanuts, pears, peppers,
potatoes, snap beans, and sweet corn. Processing factors for grapes
were calculated using concentration factors (grape juice = 1.2X,
raisins = 4.2X). Secondary residues for meat and milk were not affected
since no animal feed items are associated with these crops. Percent of
crop treated values and anticipated residues were not used.
    ii. Chronic exposure. In conducting this chronic dietary risk
assessment the Dietary Exposure Evaluation Model (DEEM\DM\) analysis
evaluated the individual food consumption as reported by respondents in
the USDA [insert 1989-1992 or 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 chronic exposure assessments: Anticipated residue values were
determined from field trial data conducted at label conditions of
maximum application rates and minimum preharvest intervals. Mean
anticipated residue values were calculated. 100% of crop treated was
assumed for all crops except hops (43%) and cottonseed-oil and
cottonseed-meal (4%). Secondary residues for meat and milk were not
affected by this use.
    iii. Cancer. For cancer risk the assessment is the same as the risk
assessment for the chronic exposure, described above.
    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 percent crop
treated (PCT) as required by section 408(b)(2)(F), EPA may require
registrants to submit data on PCT.
    The Agency used percent crop treated (PCT) information as follows:
100% of crop treated was assumed for all crops except hops (43%) and
cottonseed-oil and cottonseed-meal (4%).
    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 underestimate 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

[[Page 57976]]

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 percent RfD or percent 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 the estimated environmental
concentration (EEC) of bifenthrin in surface water for acute exposures
is 0.1 ppb. The EEC for chronic exposures was estimated to be 0.032 ppb
for surface water. The ground water screening concentration was 0.006
ppb. For the purposes of the acute and chronic risk assessments, the
estimated maximum concentration for bifenthrin in surface and ground
waters (0.01 ppb for acute, and 0.023 for chronic) was used.
    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: lawns to control flea infestation, pets
and as a termiticide. Registered termiticide use of bifenthrin
constitutes a chronic exposure scenario; however, the exposure is
considered negligible, considering the application technique of the
termiticide use (buried underground) and the fact that vapor pressure
of bifenthrin is extremely low. The Agency conducted a residential
exposure assessment for the lawn care uses of bifenthrin. 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-term 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 (non-dietary).
    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 November 26, 1997 (62 FR 62961).

C. Safety Factor for Infants and Children

    1. Safety factor for infants and children--i. 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 MOE analysis or through using uncertainty
(safety) factors in calculating a dose level that poses no appreciable
risk to humans.
    ii. Developmental toxicity studies. In a developmental study in
rats, the NOAEL for maternal toxicity was 1 milligram/kilogram/day (mg/
kg/day), based upon tremors observed at the LOAEL of 2 mg/kg/day. The
NOAEL for developmental toxicity was 1 mg/kg/day, based upon the
increased incidence of hydroureter observed at the LOAEL of 2 mg/kg/
day. In a developmental study in rabbits, the NOAEL for maternal
toxicity was 2.67 mg/kg/day, based upon head and forelimb twitching
seen at the LOAEL of 4 mg/kg/day. There were no developmental effects
observed.
    iii. Reproductive toxicity study. In the rat reproduction study,
parental toxicity occurred as decreased body weight at the LOAEL of 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).
    iv. Prenatal and postnatal sensitivity. 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. 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.

[[Page 57977]]

    v. 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. Based on the
above, EPA concludes that reliable data support use of the standard
100-fold UF, and that an additional UF is not needed to protect the
safety of infants and children. Therefore, the FQPA safety factor for
enhanced sensitivity of infants and children was reduced to 1X.

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 USEPA Office of Water are used to calculate
DWLOCs: 2L/70 kg (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 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 infants
(up to 1 year old) and 99.7% % of the aPAD for children (1 to 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 estimated environmental concentrations 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 water   Ground water
Population subgroup       aPAD (mg/kg)   %aPAD (Food)      EEC (ppb)       EEC (ppb)    Acute DWLOC (ppb)
---------------------------------------------------------------------------------------------------------
U.S. population              0.01           60               0.10            0.10             140
Females 13 + yrs old         0.01           40               0.10            0.10             180
Children (1-6 yrs old)       0.01           99.7             0.10            0.10               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, and 8.2% of the cPAD for children (1 to 6 years old), the
subpopulation at greatest exposure. Bifenthrin is also registered for
residential use on outdoor lawn/gardens, inside households, pets and as
a termiticide. Based on the use pattern, chronic residential exposure
to residues of the bifenthrin is not expected. In addition, despite the
potential for chronic dietary exposure to bifenthrin in drinking water,
after calculating the DWLOCs and comparing them to conservative model
estimated environmental concentrations 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 water    Ground water      Chronic
Population subgroup       cPAD mg/kg/day    %cPAD (Food)      EEC (ppb)       EEC (ppb)      DWLOC (ppb)
--------------------------------------------------------------------------------------------------------
 U.S. population............  0.015..........  3.0............  0.032........  0.032..........  530
Infants,  1 yr old..........  0.015..........  3.0............  0.032........  0.032..........  450
Children (1-6 yrs old)......  0.015..........  3.0............  0.032........  0.032..........  140
--------------------------------------------------------------------------------------------------------

    3. Short-term 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- and intermediate-term residential exposure. Registered
termiticide use of bifenthrin constitutes a chronic exposure scenario;
however, the exposure is considered negligible. The Agency has
determined that it is appropriate to aggregate chronic food and water
and short-term and intermediate-term exposures for bifenthrin.
    Using the exposure assumptions described in this unit for short-
term and intermediate-term exposures, EPA has concluded that food and
residential exposures aggregated result in aggregate MOEs of 940 for
adults, 350 for children

[[Page 57978]]

ages 1 to 6 years, and 470 for infants less than 1 year old, based on
chronic food and residential use, e.g., turf representing the worst
case residential exposure scenario. These aggregate MOEs do not exceed
the Agency's level of concern for aggregate exposure to food and
residential uses. In addition, short-term and intermediate-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 or intermediate-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-Term and Intermediate-Term Exposure to Bifenthrin
----------------------------------------------------------------------------------------------------------------------
                                                                                                      Short-Term and
Population subgroup     Aggregate MOE (food +   Aggregate level of   Surface water   Ground water   Intermediate-Term
                             residential)         concern (LOC)        EEC (ppb)      EEC (ppb)        DWLOC (ppb)
----------------------------------------------------------------------------------------------------------------------
Adult (male)..................  940.................  100.............  0.032.........  0.032............  320
Adult (female)................  940.................  100.............  0.032.........  0.032............  270
Children 1-6 yrs old..........  350.................  100.............  0.032.........  0.032............   71
----------------------------------------------------------------------------------------------------------------------

    4. Aggregate cancer risk for U.S. population. A quantitative (Q1*)
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 RfD. For the U.S.
population, only 3.0% of the cPAD (cRfD) is occupied by chronic food
exposure. Based on a comparison of the calculated DWLOCs and the
estimated exposure to bifenthrin in drinking water (0.032 ppb), 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

A. Analytical Enforcement Methodology

    Adequate enforcement methods are available for determination of the
regulated bifenthrin residue in plants. The data gathering method is
FMC method P-2132M, with a limit of quantitation of 0.05 ppm (given as
0.055 in some cases). This method is a variation of two other methods
which have been submitted for inclusion in PAM II (FMC's Methods P-1031
and RAN-0140. This method has been adequately validated and is adequate
for data collection. The method may be requested from: Calvin Furlow,
PIRIB, 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.

B. International Residue Limits

    No Codex, Canadian, or Mexican maximum residue levels (MRL) have
been established for residues of bifenthrin in/on potatoes.
International harmonization is therefore not an issue for this
tolerance.

VI. Conclusion

    Therefore, the tolerance is established for residues of bifenthrin,
in or on 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. 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-301047 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
27, 2000.
    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."

[[Page 57979]]

    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 dcket. 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-301047 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-commat;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 file format 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 tolerance under FFDCA section 408(d)
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 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 petition under FFDCA section 408(d), 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 15, 2000.

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. 321(q), (346a) and 371.

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

[[Page 57980]]

Sec. 180.442   Bifenthrin; tolerances for residues.

* * * * *
    (b)* * *

---------------------------------------------------------------------------

Commodity               Parts per million        Expiration/Revocation date
---------------------------------------------------------------------------
                         *        *        *        *      *
Potato                        0.05                    12/31/2002
                         *        *        *        *      *
---------------------------------------------------------------------------

* * * * *

[FR Doc. 00-24785 Filed 9-26-00; 8:45 am]
BILLING CODE 6560-50-S