[Federal Register Volume 66, Number 188 (Thursday, September 27, 2001)]
[Rules and Regulations]
[Pages 49300-49308]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-24199]


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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).

[[Page 49301]]


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:[email protected].

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: 
[email protected].

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 [email protected], 
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: [email protected]. 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