[Federal Register Volume 62, Number 90 (Friday, May 9, 1997)]
[Rules and Regulations]
[Pages 25518-25524]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-12195]



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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 180

[OPP-300484; FRL-5715-6]

RIN 2070-AB78


Cyfluthrin; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final Rule.

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SUMMARY: This regulation establishes time-limited tolerances with an 
expiration date of November 15, 1997 for residues of the pyrethroid 
cyfluthrin in or on the food commodities group citrus fruit and a 
maximum residue limit for cyfluthrin on citrus oil and dried pulp. A 
petition was submitted by Bayer Corporation to EPA under the Federal 
Food Drug and Cosmetic Act (FFDCA) as amended by the Food Quality 
Protection Act of 1996 (Pub. L. 104-170) requesting the tolerance. This 
tolerance will expire and is revoked on November 15, 1997.

DATES: This regulation becomes effective May 9, 1997. Written 
objections and requests for hearings must be received by July 8, 1997.

ADDRESSES: Written objections and hearing requests, identified by the 
docket control number, [OPP-300484], must be submitted to: Hearing 
Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M St., 
SW., Washington, DC 20460. Fees accompanying objections and hearing 
requests shall be labeled ``Tolerance Petition Fees'' and forwarded to: 
EPA Headquarters Accounting Operations Branch, OPP (Tolerance Fees), 
P.O. Box 360277M, Pittsburgh, PA 15251. A copy of any objections and 
hearing requests filed with the Hearing Clerk identified by the docket 
control number, [OPP-300484], should be submitted to: Public Response 
and Program Resources Branch, Field Operations Division (7506C), Office 
of Pesticide Programs, Environmental Protection Agency, 401 M St., SW., 
Washington, DC 20460. In person, bring a copy of objections and hearing 
requests to Rm. 1132, CM#2, 1921 Jefferson Davis Hwy., Arlington.
    A copy of objections and hearing requests filed with the Hearing 
Clerk may also be submitted electronically by sending electronic mail 
(e-mail) to: OPP[email protected]. Copies of objections and 
hearing requests must be submitted as an ASCII file avoiding the use of 
special characters and any form of encryption. Copies of objections and 
hearing requests will also be accepted on disks in WordPerfect 5.1 file 
format or ASCII file format. All copies of objections and hearing 
requests in electronic form must be identified by the docket number 
[OPP-300484]. No Confidential Business Information (CBI) should be 
submitted through e-mail. Electronic copies of objections and hearing 
requests on this rule may be filed online at many Federal Depository 
Libraries.

FOR FURTHER INFORMATION CONTACT: By mail: George T. LaRocca, Product 
Manager (PM) 13, Registration Division (7505C), Office of Pesticide 
Programs, Environmental Protection Agency, 401 M St., SW., Washington, 
DC 20460. Office location and telephone number: Rm. 204, CM #2, 1921 
Jefferson Davis Highway, Arlington, VA, (703) 305-6100, e-mail: 
[email protected].
SUPPLEMENTARY INFORMATION: EPA issued a notice, published in the July 
13, 1994 Federal Register (59 FR 35717)(FRL-4871-5), which announced 
that Miles Corporation had submitted a pesticide petition (4F4313) to 
EPA and a food/feed additive petition (FAP) 4H5687 to EPA. Pesticide 
petition 4F4313 requests that the Administrator, pursuant to section 
408(d) of the Federal Food, Drug an Cosmetic Act, 21 U.S.C. 346a(d), 
amend 40 CFR 180.436 to establish tolerances for residues of the 
insecticide cyfluthrin, ([cyano-[4-fluoro-3-phenoxyphenyl]-methyl-3-
[2,2-dicloroethenyl]-2,2-dimethylcyclopropanecarboxylate]; CAS No. 
68359-37-5; EPA Chemical No. 128831) in or on the food commodities 
group citrus, fruits at 0.2 parts per million (ppm). Food/feed additive 
petition 4H5687 requests that the Administrator, pursuant to section 
409(e) of the FFDCA (21 U.S.C. 348), amend 40 CFR parts 185 and 186 by 
establishing a food/feed additive regulation for cyfluthrin in or on 
the process commodities citrus oil and citrus dried pulp at 0.3 ppm. 
The Agency was unable to publish a final rule prior to the enactment of 
the Food Quality and Protection Act (FQPA) of 1996. Because of new 
procedures under FQPA Bayer Corporation was required to submit a new 
notice of filing requesting issuance of these tolerances in compliance 
with FQPA.
    In the Federal Register of March 14, 1997 (62 FR 12182)(FRL-5990-2) 
EPA issued a second notice of filing to bring the notice into 
conformity with the FQPA. The notice contained a summary of the 
petition prepared by the petitioner and this summary contained 
conclusions and assessments to support its conclusion that the petition 
complied with FQPA.
    There were no comments received in response to the notices of 
filing.

I. Background and Statutory Authority

    The Food Quality Protection Act of 1996 (FQPA) (Pub. L. 104-170) 
was signed into law August 3, 1996. FQPA amends both the Federal Food, 
Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 301 et seq., and the Federal 
Insecticide, Fungicide, and Rodenticide Act (FIFRA), 7 U.S.C. 136 et 
seq. The FQPA amendments went into effect immediately. Among other 
things, FQPA amends FFDCA to bring all EPA pesticide tolerance-setting 
activities under a new section 408 with a new safety standard and new 
procedures.
    New section 408(b)(2)(A)(i) 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, 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 408(b)(2)(D) specifies factors EPA is to consider 
in establishing a tolerance. Section 408(b)(3) requires EPA to 
determine that there is a practical method for detecting and measuring 
levels of the pesticide chemical residue in or on food and that the 
tolerance be set at a level at or above the limit of detection of the 
designated method. Section 408(b)(4) requires EPA to determine whether 
a maximum residue level has been established for the pesticide chemical 
by the Codex Alimentarius Commission. If so, and EPA does not propose 
to adopt that level, EPA must publish for public comment a notice 
explaining the reasons for departing from the Codex level.

II. Risk Assessment and Statutory Findings

    EPA performs a number of analyses to determine the risks from 
aggregate exposure to pesticide residues. First, EPA determines the 
toxicity of

[[Page 25519]]

pesticides based primarily on toxicological studies using laboratory 
animals. These studies address many adverse health effects, including 
(but not limited to) reproductive effects, developmental toxicity, 
toxicity to the nervous system, and carcinogenicity. For many of these 
studies, a dose response relationship can be determined, which provides 
a dose that causes adverse effects (threshold effects) and doses 
causing no observed effects (NOEL).
    Once a study has been evaluated and the observed effects have been 
determined to be threshold effects, EPA generally divides the NOEL from 
the study with the lowest NOEL by an uncertainty factor (usually 100 or 
more) to determine the Reference Dose (RfD). The RfD is a level at or 
below which daily aggregate exposure over a lifetime will not pose 
significant risks to human health. An uncertainty factor (sometimes 
called a ``safety factor'') of 100 is commonly used since it is assumed 
that people may be up to 10 times more sensitive to pesticides than the 
test animals, and that one person or subgroup of the population (such 
as infants and children) could be up to 10 times more sensitive to a 
pesticide than another. In addition, EPA assesses the potential risks 
to infants and children based on the weight of the evidence of the 
toxicology studies and determines whether an additional uncertainty 
factor is warranted. Thus, an aggregate daily exposure to a pesticide 
residue at or below the RfD (expressed as 100 percent or less of the 
RfD) is generally considered acceptable by EPA.
    Lifetime feeding studies in two species of laboratory animals are 
conducted to screen pesticides for cancer effects. When evidence of 
increased cancer is noted in these studies, the Agency conducts a 
weight of the evidence review of all relevant toxicological data 
including short term and mutagenicity studies and structure activity 
relationship. Once a pesticide has been classified as a potential human 
carcinogen, different types of risk assessments (e.g., linear low dose 
extrapolations or margin of exposure calculation based on the 
appropriate NOEL) will be carried out based on the nature of the 
carcinogenic response and the Agency's knowledge of its mode of action.
    In examining aggregate exposure, FQPA requires that EPA take into 
account available and reliable information concerning exposure from the 
pesticide residue in the food in question, residues in other foods for 
which there are tolerances, and other non-occupational exposures, such 
as where residues leach into groundwater or surface water that is 
consumed as drinking water. Dietary exposure to residues of a pesticide 
in a food commodity are estimated by multiplying the average daily 
consumption of the food forms of that commodity by the tolerance level 
or the anticipated pesticide residue level. The Theoretical Maximum 
Residue Contribution (TMRC) is an estimate of the level of residues 
consumed daily if each food item contained pesticide residues equal to 
the tolerance. The TMRC is a ``worst case'' estimate since it is based 
on the assumptions that food contains pesticide residues at the 
tolerance level and that 100 percent of the crop is treated by 
pesticides that have established tolerances. If the TMRC exceeds the 
RfD or poses a lifetime cancer risk that is greater than approximately 
one in a million, EPA attempts to derive a more accurate exposure 
estimate for the pesticide by evaluating additional types of 
information (anticipated residue data and/or percent of crop treated 
data) which show, generally, that pesticide residues in most foods when 
they are eaten are well below established tolerances.
    Consistent with sections 408(b)(2)(C) (D), EPA has reviewed the 
available scientific data and other relevant information in support of 
this action. EPA has also assessed the toxicology data base for 
cyfluthrin its evaluation of application for registration on citrus. 
EPA has sufficient data to assess the hazards of cyfluthrin and to make 
a determination on aggregate exposure, consistent with section 
408(b)(2), for granting time-limited tolerances for residues of 
cyfluthrin on citrus at 0.2 ppm, and citrus oil and dried pulp at 0.3 
ppm. EPA's assessment of the database, dietary exposures and risks 
associated with establishing these tolerances follows:

A. Toxicology Database

    EPA has evaluated the available toxicity data and considered its 
validity, completeness, and reliability as well as the relationship of 
the results of the studies to human risk. EPA has also considered 
available information concerning the variability of the sensitivities 
of major identifiable subgroups of consumers, including infants and 
children. The nature of the toxic effects caused by cyfluthrin are 
discussed below.
    1. Acute studies. A battery of acute toxicity studies placing 
technical cyfluthrin in toxicity category II.
    2. Chronic studies. i. A 12-month chronic feeding study in dogs 
with a no-observed effect level (NOEL) of 4 milligram per kilogram per 
day (mg/kg/day). The lowest effect level (LEL) for this study is 
established at 16 mg/kg/day, based on slight ataxia, increased 
vomiting, diarrhea and decreased body weight.
    ii. A 24-month chronic feeding/carcinogenicity study in rats with a 
NOEL of 2.5 mg/kg/day and LEL of 6.2 mg/kg/day, based on decreased body 
weights in males, decreased food consumption in males, and inflammatory 
foci in the kidneys in females.
    iii. A 24-month carcinogenicity study in mice. There were no 
carcinogenic effects observed under the conditions of the study.
    3. Developmental and reproductive effects studies. i. An oral rat 
developmental toxicity study, the maternal (systemic) NOEL is 3 mg/kg/
day. The maternal (systemic) lowest observed effect level (LOEL) of 10 
mg/kg/day was based on behavioral changes in gait and coordination. The 
developmental (fetal) NOEL is 30 mg/kg/day (highest dose tested). No 
developmental effects were noted.
    ii. An oral rat developmental toxicity study, the maternal 
(systemic) NOEL is 10 mg/kg/day (highest dose tested). The 
developmental (fetal) NOEL is 10 mg/kg/day (highest dose tested). No 
developmental effects were noted.
    iii. A rat inhalation developmental toxicity study, the maternal 
(systemic) NOEL is 0.46 mg/m3. The maternal (systemic) LOEL 
2.55 mg/m3 was based on decreased body weight gain and 
reduced food efficiency. The developmental (fetal) NOEL is 0.46 mg/
m3. The developmental (fetal) LOEL of 2.55 mg/m3 
is based on reduced fetal and placental weight, reduced ossification in 
the phalanges, metacarpals and vertebrae.
    iv. An oral rabbit developmental toxicity study, the maternal 
(systemic) NOEL is 20 mg/kg/day. The maternal (systemic) LOEL of 60 mg/
kg/day was based on decreased body weight gain and food consumption 
during the dosing period. The developmental (fetal) NOEL is 20 mg/kg/
day. The developmental (fetal) LOEL is 60 mg/kg/day based on 
statistically significant increase in the numbers of resorptions and 
statistically significant post-implantation loss.
    v. An oral 3-generation reproduction study, the systemic NOEL is 
1.5 mg/kg/day. The systemic LOEL of 4.5 mg/kg/day was based on body 
weight decrease in pups. The reproductive (fetal) NOEL is 4.5 mg/kg/
day. The reproductive (fetal) LOEL is 7.5 mg/kg/day based on decreased 
pup viability.

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    4. Other studies. i. Mutagenicity tests were conducted, including 
several gene mutation assays (reverse mutation and recombination assays 
in bacteria and a Chinese hamster ovary(CHO)/HGPRT assay); a structural 
chromosome aberration assay (CHO/sister chromatid exchange assay); and 
an unscheduled DNA synthesis assay in rat hepatocytes. All tests were 
negative for genotoxicity.
    ii. A metabolism study in rats showed that cyfluthrin is rapidly 
absorbed and excreted, mostly as conjugated metabolites in the urine, 
within 48 hours. An enterohepatic circulation was observed. The NOEL 
for dermal and systemic toxicity was 1,000 mg/kg/day (limit dose). New 
Zealand White strain rabbits were given 15 dermal applications at 0, 
100, 500, or 1,000 mg/kg/day for 21 days. Under the conditions of the 
test, there was no evidence of treatment-related toxicity from dermal 
application at doses up to 1,000 mg/kg/day.
    The toxicity database for cyfluthrin is essentially complete. Data 
lacking but desirable are a new 21-day subchronic dermal study, an 
acute neurotoxicity study in rats, a 90-day neurotoxicity study in 
rats, and a dermal sensitization study on the end-use product, 
Baythroid 2. These studies have been submitted to the Agency and are 
currently under review, with the exception of the acute and 90-day 
neurotoxicity studies. Bayer Corporation has committed to submit the 
results of these neurotoxicity studies to the Agency by July 1997. 
Although these data are lacking, the Agency believes it has sufficient 
toxicity data to support the proposed tolerance and these additional 
studies will not significantly change its risk assessment.

B. Toxicological Profile

    1. Toxicity endpoints for dietary exposure-- i. acute. To assess 
acute dietary risk, the Agency used an endpoint of 20 mg/kg/day, the 
NOEL from the oral developmental toxicity study in rabbits. This risk 
assessment will evaluate acute dietary risk to females 13+ years and 
older.
    ii. Chronic. A reference dose (RfD) of 0.025 mg/kg/day has been 
estimated by the Agency. The RfD was established based on the rat 
chronic feeding/carcinogenicity study with a NOEL of 2.5 mg/kg/day and 
an uncertainty factor of 100.
    iii. Carcinogenicity. Cyfluthrin has been classified as a Group E 
chemical (evidence of non-carcinogenicity for humans) by the Agency. 
The classification was based on a lack of convincing evidence of 
carcinogenicity in adequate studies with two animal species, rat and 
mouse.
    2. Toxicity endpoints for non-dietary exposure--i. short and 
intermediate term residential dermal and/or inhalation exposure. For 
short-and intermediate term dermal exposure, the agency used the dermal 
toxicity NOEL of 250 mg/kg/day (highest dose tested) from the 21-day 
dermal rabbit toxicity study. For short- and intermediate-term 
inhalation exposure, the Agency used the inhalation developmental study 
in rats, where the maternal threshold NOEL was 0.00046 based on 
decreased body weight gain and reduced relative food efficiency at the 
LOEL of 0.0025 milligrams per liter (mg/L). The developmental NOEL of 
0.00046 mg/l was based on reduced fetal weights, reduced placental 
weights, and reduced ossification in the phalanx, metacarpals and 
vertebrae at the LOEL of 0.0025 mg/L (0.46 mg/kg/day).
    ii. Chronic residential exposure. Based upon the registered indoor/
outdoor uses of cyfluthrin, exposure from these uses are expected to be 
from inhalation and/or dermal contact. EPA has no quantitative data on 
dermal absorption for the formulations of this pesticide, nor does it 
have reliable data for indoor/outdoor exposures. Estimations of outdoor 
residential exposure have been required for cyfluthrin in a data call-
in issued in 1995. These data are being generated by the Outdoor 
Residential Exposure Task Force. Without these data EPA cannot 
determine the risk to the public exposed by the non-dietary uses of 
this pesticide. For this reason EPA is using a maximum default 
assumption of 20% of the RfD (0.025 mg/kg/day) as the exposure for 
these uses.
    iii. Dermal penetration. The default value of 100% is being used 
for dermal penetration in the absence of actual data.

C. Aggregate Exposure

     1. From food and feed uses. The primary source of human exposure 
to cyfluthrin will be from ingestion of both raw and processed food 
commodities treated with cyfluthrin. These commodities include the 
current citrus fruit group plus citrus oil and dried pulp and other 
commodities listed in 40 CFR 180.436, 185.1250 and 186.1250. Any 
secondary residues occurring in cattle meat, meat byproducts, milk and 
fat from the addition of the feed items citrus dried pulp will be 
covered by existing tolerances. There is no reasonable expectation of 
finite residues in poultry and swine, therefore the necessity or 
adequacy of tolerances for these commodities is not an issue relevant 
to the use on citrus.
    The Agency has requested additional confirmatory animal feeding 
study data on levels of the metabolite DCVA (3-(2,2-dichloroethenyl)-
2,2-dimethylcyclopropane carboxylic acid) in animal commodities.
    2. From potable (drinking) water. There is no established Maximum 
Concentration Level for residues of cyfluthrin in drinking water. 
Although data indicate little potential for soil mobility or leaching, 
cyfluthrin is moderately persistent. In examining aggregate exposure, 
FQPA directs EPA to consider available information concerning exposures 
from the pesticide residue in food and all other non-occupational 
exposures. The primary non-food sources of exposure the Agency looks at 
include drinking water (whether from groundwater or surface water), and 
exposure through pesticide use in indoor/outdoor residential sites.
    Because the Agency lacks sufficient water-related exposure data to 
complete a comprehensive drinking water risk assessment for many 
pesticides, EPA has commenced and nearly completed a process to 
identify a reasonable yet conservative bounding figure for the 
potential contribution of water related exposure to the aggregate risk 
posed by a pesticide. In developing the bounding figure, EPA estimated 
residue levels in water for a number of specific pesticides using 
various data sources. The Agency then applied the estimated residue 
levels, in conjunction with appropriate toxicological endpoints (RfD's 
or acute dietary NOEL's) and assumptions about body weight and 
consumption, to calculate, for each pesticide, the increment of 
aggregate risk contributed by consumption of contaminated water. While 
EPA has not yet pinpointed the appropriate bounding figure for 
consumption of contaminated water, the ranges the Agency is continuing 
to examine are all below the level that would cause cyfluthrin to 
exceed the RfD if the tolerance being considered in this document were 
granted. The Agency has therefore concluded that the potential 
exposures associated with cyfluthrin in water, even at the higher 
levels the Agency is considering as a conservative upper bound, would 
not prevent the Agency from determining that there is a reasonable 
certainty of no harm if the tolerance is granted.
    3. From non-dietary uses. Cyfluthrin is registered for use on non-
food sites including golf courses, lawns, ornamental shrubs, indoor 
foggers, and wood surfaces. Upon considering the registered uses, 
formulation types, persistence, and toxicological endpoints, and in 
accordance with the Agency's Interim Decision Logic (PR

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97-1, Jaunary 31, 1997), EPA has determined that, in the absence of 
exposure data, the registered non-dietary, non-occupational uses of 
cyfluthrin should be assigned a default value of 20% of the acceptable 
aggregate chronic; and short- and intermediate-term risk.
    4. Cumulative exposure to substances with common mechanism of 
toxicity. Cyfluthrin is a member of the synthetic pyrethroid class of 
pesticides. 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.'' The Agency believes that ``available 
information'' in this context might include not only toxicity, 
chemistry, and exposure data, but also scientific policies and 
methodologies for understanding common mechanisms of toxicity and 
conducting cumulative risk assessments. For most pesticides, although 
the Agency has some information in its files that may turn out to be 
helpful in eventually determining whether a pesticide shares a common 
mechanism of toxicity with any other substances, EPA does not at this 
time have the methodologies to resolve the complex scientific issues 
concerning common mechanism of toxicity in a meaningful way. EPA has 
begun a pilot process to study this issue further through the 
examination of particular classes of pesticides. The Agency hopes that 
the results of this pilot process will increase the Agency's scientific 
understanding of this question such that EPA will be able to develop 
and apply scientific principles for better determining which chemicals 
have a common mechanism of toxicity and evaluating the cumulative 
effects of such chemicals. The Agency anticipates, however, that even 
as its understanding of the science of common mechanisms increases, 
decisions on specific classes of chemicals will be heavily dependent on 
chemical specific data, much of which may not be presently available.
    Although at present the Agency does not know how to apply the 
information in its files concerning common mechanism issues to most 
risk assessments, there are pesticides as to which the common mechanism 
issues can be resolved. These pesticides include pesticides that are 
toxicologically dissimilar to existing chemical substances (in which 
case the Agency can conclude that it is unlikely that a pesticide 
shares a common mechanism of activity with other substances) and 
pesticides that produce a common toxic metabolite (in which case common 
mechanism of activity will be assumed).
    Although cyfluthrin is structurally similar to other members of the 
synthetic pyrethroid class of insecticides, EPA does not have, at this 
time, available data to determine whether cyfluthrin has a common 
mechanism of toxicity with other substances or how to include this 
pesticide in a cumulative risk assessment. For the purposes of this 
tolerance action, therefore, EPA has not assumed that cyfluthrin has a 
common mechanism of toxicity with other substances.

D. Aggregate Risk Assessment

    1. Acute aggregate risk. The acute dietary (food only) risk 
assessment used tolerance level residues and assumed 100% crop-treated. 
Thus, this acute dietary exposure estimate is considered conservative; 
refinement using anticipated residue values and percent crop-treated 
data in conjunction with Monte Carlo analysis would result in a lower 
acute dietary exposure estimate. A Monte Carlo analysis is a 
probabilistic risk assessment methodology in which a distribution of 
expected residues (also consumption estimates) is considered, instead 
of a single value such as the tolerance level. The estimated acute 
dietary risk, using a high-end exposure of 0.03 mg/kg/day, resulted in 
an MOE = 666 for the population of concern (females, 13+ years).
    The acute aggregate risk assessment takes into account exposure 
from dietary food only. As indicated above, although EPA has not 
identified a water exposure figure based upon available environmental 
data, cyfluthrin is not expected to be mobile in soil or water 
environments and poses relatively little threat to drinking water. 
Theoretically, it is also possible that a residential, or other non-
dietary, exposure could be combined with the acute total dietary 
exposure from food and water. However, the Agency does not believe that 
aggregating multiple exposure to large amounts of pesticide residues in 
the residential environment via multiple products and routes for a 1 
day exposure is a reasonably probable event. It is highly unlikely 
that, in 1 day, an individual would have multiple high-end exposures to 
the same pesticide by treating their lawn and garden, treating their 
house via crack and crevice application, swimming in a pool, and be 
maximally exposed in the food and water consumed. Additionally, the 
concept of an acute exposure as a single exposure does not allow for 
including post-application exposures, in which residues decline over a 
period of days after application. Therefore, the Agency believes that 
residential exposures are more appropriately included in the short-term 
exposure scenario.
    An acute dietary MOE of greater than 100 would not be of concern to 
EPA. As indicated above, the MOE for females 13+ years was calculated 
to be 666. Under any bounding assumption EPA is considering for 
exposure from drinking water, this MOE would not be reduced to less 
than 100. Therefore, EPA has no acute aggregate concern due to exposure 
to cyfluthrin through food and drinking water.
    2. Short- and intermediate term aggregate risk. In the absence of 
exposure data, EPA is reserving a default value of 20% for residential 
exposures. However, as non-quantifiable exposures can not be included 
in MOE calculations, the short-term MOE will include only dietary 
exposure. Since the short term NOEL is based on a 21 day dermal 
exposure toxicity, the dermal exposure will be adjusted for a dietary 
endpoint (from the developmental study). The NOEL from the 
developmental study (20 mg/kg/day) is 12.5-fold lower than that of the 
21-day dermal study (250 mg/kg/day). The adjusted chronic dietary 
exposure is thus 0.339 mg/kg/day (TMRC of 0.0271 mg/kg/day multiplied 
by 12.5). As the calculated MOE for children (1 to 6 years old) is 737 
(short term NOEL of 250 mg/kg/day divided by adjusted dietary exposure 
of 0.339 mg/kg/day), the addition of any bounding assumption EPA is 
considering for exposures from dietary water and residential sources is 
unlikely to result in a MOE of <100. EPA thus considers the short- and 
intermediate term risk to be acceptable for the purposes of 
establishing the proposed tolerances.
    3. Chronic aggregate risk. The chronic dietary (food only) risk 
assessment used anticipated residues and percent crop treated for 
certain crops. Percent of crop treated estimates are derived from 
Federal and private market survey data. Typically, a range of estimates 
are supplied and the upper end of this range is assumed for the 
exposure assessment. By using the upper end estimate of percent of crop 
treated, the Agency is reasonably certain that exposure is not 
understated for any significant subpopulation group. Further, regional 
consumption information is taken into account through EPA's computer-
based model for evaluating the exposure of significant subpopulations, 
including several regional groups, to pesticide residues. The resulting 
exposure

[[Page 25522]]

estimates should therefore be viewed as partially refined. Further 
refinement using anticipated residues and percent crop treated for all 
commodities would result in lower dietary exposure estimates. For 
chronic dietary (food only) risk estimates, the population subgroup 
with the largest percentage of the RfD occupied is children (non-
nursing infants, <1 years old) at 13% of the RfD.
    Section 408 (b)(2)(E) requires that, if EPA relies upon anticipated 
residue levels in setting a tolerance, EPA must require that data be 
submitted 5 years after approval of the tolerance on whether the 
anticipated residue level remains accurate. Because this tolerance is 
limited to less than 1 year, data are not being required at this time.
    The aggregated chronic risk is equal to the sum of the chronic risk 
for food, drinking water, and indoor and outdoor residential exposures. 
For cyfluthrin, residential exposure data are lacking although the 
potential for exposure does exist. Therefore, residential exposure was 
also aggregated with dietary exposure in the chronic risk assessment. 
The aggregated chronic risk for the population subgroup non-nursing 
infants less than 1 year old from combined sources is 33% of the RfD 
(dietary = 13% + non-occupational = 20%). Under any bounding 
assumptions EPA is considering for exposure from drinking water, 
exposure to cyfluthrin would not exceed the RfD. EPA therefore 
concludes that there is reasonable certainty that no harm will result 
to consumers, including infants and children, from aggregate exposure 
to cyfluthrin residues.
    4. Determination of safety for infants and children. FFDCA section 
408 provides that EPA shall apply an additional tenfold margin of 
safety for infants and children in the case of threshold effects to 
account for pre- and post-natal toxicity and the completeness of the 
database unless EPA determines that a different margin of safety will 
be safe for infants and children. Margins of safety are incorporated 
into EPA risk assessments either directly through use of a margin of 
exposure analysis or through using uncertainty (safety) factors in 
calculating a dose level that poses no appreciable risk to humans. In 
either case, EPA generally defines the level of appreciable risk as 
exposure that is greater than 1/100 of the NOEL in the animal study 
appropriate to the particular risk assessment. This hundredfold 
uncertainty (safety) factor/margin of exposure (safety) is designed to 
account for combined inter- and intra-species variability. EPA believes 
that reliable data support using the standard hundredfold margin/factor 
not the additional tenfold margin/factor when EPA has a complete data 
base under existing guidelines and when the severity of the effect in 
infants or children or the potency or unusual toxic properties of a 
compound do not raise concerns regarding the adequacy of the standard 
margin/factor.
    In assessing the potential for additional sensitivity of infants 
and children to residues of cyfluthrin, EPA considered data from oral 
developmental toxicity studies in the rat and rabbit, as well data from 
a 2-generation reproduction study in the rat. The developmental 
toxicity studies are designed to evaluate adverse effects on the 
developing organism resulting from pesticide exposure during prenatal 
development to the mothers. Reproduction studies provide information 
relating to effects from exposure to the pesticide on the reproductive 
capability of mating animals and data on systemic toxicity.
    5. Pre-natal effects. In the oral rat developmental toxicity 
studies, maternal (systemic) effects consisting of behavioral changes 
in gait and coordination were the basis of the maternal LOEL of 10 mg/
kg/day. No developmental (fetal) effects were noted in doses up to 30 
mg/kg/day (highest dose tested). In the oral rabbit developmental 
study, no developmental toxicity was observed at doses where maternal 
toxicity was noted. The maternal (systemic) NOEL is 20 mg/kg/day and 
the maternal (systemic) LOEL of 60 mg/kg/day was based on decreased 
body weight gain and food consumption. The developmental (fetal) NOEL 
is 20 mg/kg/day and the developmental (fetal) LOEL of 60 mg/kg/day was 
based on increases in the numbers of resorptions and post-implantation 
loss.
    In an inhalation developmental toxicity study, the maternal 
(systemic) and developmental (fetal) NOELs are 0.46 mg/m3 
and the maternal (systemic) and developmental (fetal) LOELs are 2.55 
mg/m3. The maternal (systemic) LOEL was based on decreased 
body weight gain and reduced food efficiency. The developmental (fetal) 
LOEL was based on reduced fetal and placental weight and reduced 
ossification. The weight of the evidence from this study would suggest 
that cyfluthrin exposure caused developmental toxicity indirectly 
through bradypnea (abnormal slowness of breathing) in the dams.
    6. Post-natal effects. In the rat 2-generation reproduction study, 
parental toxicity was observed at 4.5 mg/kg/day based on body weight 
decrease in pups (weaned for the next generation). The reproductive 
(fetal) NOEL is 4.5 mg/kg/day. The reproductive (fetal) LOEL is 7.5 mg/
kg/day based on decreased pup viability.
    These data taken together suggest minimal concern for developmental 
or reproductive toxicity and do not indicate any increased pre- or 
post-natal sensitivity. Therefore, EPA concludes that reliable data 
support use of a hundredfold safety factor, and an additional tenfold 
safety factor is not needed to protect the safety of infants and 
children.

E. Other Considerations

    1. Endocrine effects. No evidence of such effects were reported in 
the toxicology studies described above. There is no evidence at this 
time that cyfluthrin causes endocrine effects.
    2. Metabolism and nature of the residue. The nature of the residue 
in plants and animals is adequately understood. The residue of concern 
is parent cyfluthrin. Any secondary residues occurring in cattle meat, 
meat by-products, milk and fat from the consumption of cyfluthrin 
treated citrus will be covered by the existing tolerances for these 
commodities.
    3. Analytical methodology. Adequate enforcement methodology (gas 
chromatography/electron capture detector) for plant and animal 
commodities is available to enforce the tolerances. EPA has provided 
information on this method to the Food and Drug Adminstration. The 
method is available to anyone who is interested in pesticide residue 
enforcement from: By mail, Calvin Furlow, Public Response and Program 
Resources Branch, Field Operations Division (7506C), Office of 
Pesticide Programs, Environmental Protection Agency, 401 M St. SW., 
Washington, DC 20460. Office location and telephone number: Crystal 
Mall #2, Rm 1128, 1921 Jefferson Davis Hwy., Arlington, VA, 703-305-
5805.
    4. International tolerances. There are no Codex, Canadian or 
Mexican maximum residue limits (MRLs) for residues of cyfluthrin in/on 
citrus.

F. Summary of Findings

    Tolerances are time-limited to allow for development and review of 
supplemental toxicity data; animal feeding data for a metabolite of 
cyfluthrin; and residential, water and cumulative exposure data. These 
tolerances will expire and be revoked by EPA on November 15, 1997. 
After that November 15, 1997, EPA will publish a document in the 
Federal Register to remove the revoked tolerances from the Code of 
Federal Regulations.

[[Page 25523]]

    EPA concludes that the time-limited tolerances will be safe. 
Therefore the tolerances are established as set forth.

III. Objections and Hearing Requests

    The new FFDCA section 408(g) provides essentially the same process 
for persons to ``Object'' to a tolerance regulation issued by EPA under 
the new section 408(d) as was provided in the old section 408 and in 
section 409. However, the period for filing objections is 60 days, 
rather than 30 days. EPA currently has procedural regulations which 
given the submission of objections and hearing requests. These 
regulations will require some modification to reflect the new law. 
However, until those modifications can be made, EPA will continue to 
use its current procedural regulations with appropriate adjustments to 
reflect the new law.
    Any person may, by July 8, 1997, file written objections to any 
aspect of this regulation and may also request a hearing on those 
objections. Objections and hearing requests must be filed with the 
Hearing Clerk, at the address given above (40 CFR 178.20). A copy of 
the objections and/or hearing requests filed with the Hearing Clerk 
should be submitted to the OPP docket for this rulemaking. The 
objections submitted must specify the provisions of the regulation 
deemed objectionable and the grounds for the objections (40 CFR 
178.25). Each objection must be accompanied by the fee prescribed by 40 
CFR 180.33(i). If a hearing is requested, the objections must include a 
statement of the factual issues on which a hearing is requested, the 
requestor's contentions on such issues, and a summary of any evidence 
relied upon by the requestor (40 CFR 178.27). A request for a hearing 
will be granted if the Administrator determines that the material 
submitted shows the following: There is genuine and substantial issue 
of fact; there is a reasonable possibility that available evidence 
identified by the requestor would, if established, resolve one or more 
of such issues in favor of the requestor, taking into account 
uncontested claims or facts to the contrary; and resolution of the 
factual issues in the manner sought by the requestor would be adequate 
to justify the action requested (40 CFR 178.32). Information submitted 
in connection with an objection or hearing request may be claimed 
confidential by marking any part or all of that information as CBI. 
Information so marked will not be disclosed except in accordance with 
procedures set forth in 40 CFR part 2. A copy of the information that 
does not contain CBI must be submitted for inclusion in the public 
record. Information not marked confidential may be disclosed publicly 
by EPA without prior notice.

IV. Public Docket

    The official record for this rulemaking, as well as the public 
version, has been established for this rulemaking under docket control 
number OPP-300484 (including comments and data submitted electronically 
as described below). A public version of this record, including 
printed, paper versions of electronic comments, which does not include 
any information claimed as CBI, is available for inspection from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
official rulemaking record is located at the Virginia address in 
``ADDRESSES'' at the beginning of this document.
    Electronic comments can be sent directly to EPA at:
    [email protected]

    Electronic comments must be submitted as an ASCII file avoiding the 
use of special characters and any form of encryption. Comment and data 
will also be accepted on disks in Wordperfect 5.1 file format or ASCII 
file format. All comments and data in electronic form must be 
identified by the docket number OPP-300484. Electronic comments on this 
proposed rule may be filed online at many Federal Depository Libraries.

V. Regulatory Assessment Requirements

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), this 
action is not a ``significant regulatory action'' and, since this 
action does not impose any information collection requirements as 
defined by the Paperwork Reduction Act, 44 U.S.C. 3501 et seq., it is 
not subject to review by the Office of Management and Budget. In 
addition, this action does not impose any enforceable duty or contain 
any unfunded mandate as described in the Unfunded Mandates Reform Act 
of 1995 (Pub. L. 104-4), or require prior consultation with State 
officials as specified by Executive Order 12875 (58 FR 58093, October 
28, 1993), or special considerations as required by Executive Order 
12898 (59 FR 7629, February 16, 1994).
    Because tolerances established on the basis of a petition under 
section 408(d) of FFDCA do not require issuance of a proposed rule, the 
regulatory flexibility analysis requirements of the Regulatory 
Flexibility Act (RFA), 5 U.S.C. 604(a), do not apply. Prior to the 
recent amendment of the FFDCA, EPA had treated such rulemakings as 
subject to the RFA; however, the amendments to the FFDCA clarify that 
no proposal is required for such rulemakings and hence that the RFA is 
inapplicable. Nonetheless, the Agency has previously assessed whether 
establishing tolerances or exemptions from tolerance, raising tolerance 
levels, or expanding exemptions adversely impact small entities and 
concluded, as a generic matter, that there is no adverse impact. (46 FR 
24950, May 4, 1981).
    Under 5 U.S.C. 801(a)(1)(A) of the Small Business Regulatory 
Enforcement Fairness Act of 1996 (Title II of Pub. L. 104-121, 110 
Stat. 847), EPA submitted 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 General Accounting 
Office prior to publication of the rule in today's Federal Register. 
This rule is not a ``major rule'' as defined by 5 U.S.C. 804(2).

List of Subjects in 40 CFR Part 180

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Pesticides and pests, Reporting and 
recordkeeping requirements.

    Dated: April 30, 1997.

James Jones,

Acting Director, Registration Division, Office of Pesticide Programs.
    Therefore, 40 CFR Chapter I is amended as follows:

PART 180--[AMENDED]

    1. The authority for part 180 continues to read as follows:
    Authority: 21 U.S.C. 346a and 371.

    2. Section 180.436 is amended by revising the introductory text to 
paragraph (a), by revising the column headings to the table in 
paragraph (a), and by alphabetically adding entries for citrus crop 
group; citrus oil; and citrus dried pulp.


Sec. 180.436  Cyfluthrin; tolerances for residues.

    (a) General. Tolerances are established for residues of the 
insecticide cyfluthrin (cyano(4-fluoro-3-phenoxyphenyl)methyl 3-(2,2-
dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate; CAS Reg. No. 
68359-37-5) in or on the following raw agricultural commodities:

------------------------------------------------------------------------
                                      Parts per   Expiration/ Revocation
              Commodity                million             date         
------------------------------------------------------------------------
                                                                        
                          *    *    *    *    *                         
Citrus crop group...................        0.2       Nov. 15, 1997     

[[Page 25524]]

                                                                        
Citrus dried pulp...................        0.3            Do.          
Citrus oil..........................        0.3            Do.          
                                                                        
                          *    *    *    *    *                         
------------------------------------------------------------------------

*    *    *    *    *

[FR Doc. 97-12195 Filed 5-8-97; 8:45 am]
BILLING CODE 6560-50-F