[Federal Register Volume 62, Number 228 (Wednesday, November 26, 1997)]
[Rules and Regulations]
[Pages 63235-63244]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-30938]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-300577; FRL-5754-8]
RIN 2070-AB78


Zeta-Cypermethrin; Pesticide Tolerance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for residues of zeta-
cypermethrin in or on cabbage at 2.0 parts per million (ppm); 
cottonseed at 0.5 ppm; lettuce, head at 10.0 ppm; onions, bulb at 0.10 
ppm; pecans at 0.05 ppm; and the fat, meat, and meat byproducts (mbyp) 
of cattle, goats, hogs, horses, and sheep at 0.05 ppm. It also removes 
time limitations for tolerances for residues of zeta-cypermethrin on 
the same commodities that expire on November 15, 1997. FMC Corporation 
requested this tolerance under the Federal Food, Drug, and Cosmetic 
Act, as amended by the Food Quality Protection Act of 1996.

DATES: This regulation is effective November 26, 1997. Objections and 
requests for hearings must be received by EPA on or before January 26, 
1998.

ADDRESSES: Written objections and hearing requests, identified by the 
docket control number, OPP-300577, 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-300577, must also be submitted to: Public Information and 
Records Integrity Branch, Information Resources and Services Division 
(7502C), Office of Pesticide Programs, Environmental Protection Agency, 
401 M St., SW., Washington, DC 20460. In person, bring a copy of 
objections and hearing requests to Rm. 1132, Crystal Mall #2, 1921 
Jefferson Davis Hwy., Arlington, VA.
    A copy of objections and hearing requests filed with the Hearing 
Clerk may also be submitted electronically by sending electronic mail 
(e-mail) to: <a href="/cdn-cgi/l/email-protection#9cf3ececb1f8f3fff7f9e8dcf9ecfdf1fdf5f0b2f9ecfdb2fbf3ea"><span class="__cf_email__" data-cfemail="513e21217c353e323a3425113421303c30383d7f3421307f363e27">[email protected]</span></a>. Follow the instructions in 
Unit VI. of this preamble. No Confidential Business Information (CBI) 
should be submitted through e-mail.

FOR FURTHER INFORMATION CONTACT: By mail: Beth Edwards, Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 401 M St., SW., Washington, DC 20460. Office 
location, telephone number, and e-mail address: Crystal Mall #2, 1921 
Jefferson Davis Hwy., Arlington, VA, (703) 305-5400, e-mail: 
<a href="/cdn-cgi/l/email-protection#8ce9e8fbedfee8ffa2eee9f8e4cce9fcede1ede5e0a2e9fceda2ebe3fa"><span class="__cf_email__" data-cfemail="3a5f5e4d5b485e4914585f4e527a5f4a5b575b5356145f4a5b145d554c">[email protected]</span></a>.

SUPPLEMENTARY INFORMATION: On June 15, 1984, EPA established time-
limited tolerances under section 408 of the Federal Food, Drug, and 
Cosmetic Act (FFDCA), 21 U.S.C. 346a(d) and 348 for residues of 
cypermethrin on cottonseed; fat, meat, and mbyp of cattle, goats, hogs, 
horses, poultry, and sheep; and milk (49 FR 24864). As additional crop 
tolerances were established, they were also made time-limited. These 
tolerances expire on November 15, 1997. FMC Corporation, on September 
15, 1997, requested that the time limitation for tolerances established 
for residues of the insecticide zeta-cypermethrin in these commodities 
be removed based on environmental effects data that they had submitted 
as a condition of the registration. FMC Corporation also submitted a 
summary of its petition as required under the FFDCA, as amended by the 
Food Quality Protection Act (FQPA) of 1996 (Pub. L 104-170).
    In the Federal Register of September 25, 1997, (62 FR 50337) (FRL-
5748-2), EPA issued a notice pursuant to section 408 of the FFDCA, 21 
U.S.C. 346a(e) announcing the filing of pesticide petitions (PP 2F2623, 
4F2986, 3F2824, 7F3498, and 4F3011) for tolerances by FMC Corporation, 
1735 Market St., Philadelphia, PA 19103. This notice included a summary 
of the petition prepared by FMC Corporation, the registrant. There were 
no comments received in response to the notice of filing.
    The petition requested that 40 CFR 180.418 be amended by removing 
the time limitation for tolerances for residues of the insecticide and 
pyrethroid, zeta-cypermethrin in or on cabbage at 2.0 ppm; cottonseed 
at 0.5 ppm; lettuce, head at 10.0 ppm; onions, bulb at 0.10 ppm; and 
pecans at 0.05 ppm. Animal commodities were not

[[Page 63236]]

included in the notice of filing but are being included in this final 
rule.
    The basis for the time-limited tolerances, that expire November 15, 
1997, was given in the October 20, 1993, Federal Register (58 FR 
54094). These time-limited tolerances were predicated on the expiration 
of pesticide product registrations that were made conditional due to 
lack of certain ecological and environmental effects data. The 
rationale for using time-limited tolerances was to encourage pesticide 
manufacturers to comply with the conditions of registration in a timely 
manner. There is no regulatory requirement to make tolerances time-
limited due to the conditional status of a product registration under 
the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as 
amended. It is current EPA policy to no longer establish time 
limitations on tolerance(s) with expiration dates if none of the 
conditions of registration have any bearing on human dietary risk. The 
current petition action meets that condition and thus the expiration 
dates associated with specific crop tolerances are being deleted.

I. Risk Assessment and Statutory Findings

    New 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) of the FFDCA 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) of the FFDCA requires EPA to give special 
consideration to exposure of infants and children to the pesticide 
chemical residue in establishing a tolerance and to ``ensure that there 
is a reasonable certainty that no harm will result to infants and 
children from aggregate exposure to the pesticide chemical residue. . 
.''
    EPA performs a number of analyses to determine the risks from 
aggregate exposure to pesticide residues. First, EPA determines the 
toxicity of 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. Second, 
EPA examines exposure to the pesticide through the diet (e.g., food and 
drinking water) and through exposures that occur as a result of 
pesticide use in residential settings.

A. Toxicity

    1. Threshold and non-threshold effects. For many animal studies, a 
dose response relationship can be determined, which provides a dose 
that causes adverse effects (threshold effects) and doses causing no-
observed effects (the ``no-observed effect level'' or ``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 
appreciable 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% or less of the RfD) is 
generally considered acceptable by EPA. EPA generally uses the RfD to 
evaluate the chronic risks posed by pesticide exposure. For shorter 
term risks, EPA calculates a margin of exposure (MOE) by dividing the 
estimated human exposure into the NOEL from the appropriate animal 
study. Commonly, EPA finds MOEs lower than 100 to be unacceptable. This 
100-fold MOE is based on the same rationale as the 100-fold uncertainty 
factor.
    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 MOE 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.
    2. Differences in toxic effect due to exposure duration. The 
toxicological effects of a pesticide can vary with different exposure 
durations. EPA considers the entire toxicity data base, and based on 
the effects seen for different durations and routes of exposure, 
determines which risk assessments should be done to assure that the 
public is adequately protected from any pesticide exposure scenario. 
Both short and long durations of exposure are always considered. 
Typically, risk assessments include ``acute,'' ``short-term,'' 
``intermediate-term,'' and ``chronic'' risks. These assessments are 
defined by the Agency as follows.
    Acute risk, by the Agency's definition, results from 1-day 
consumption of food and water, and reflects toxicity which could be 
expressed following a single-oral exposure to the pesticide residues. 
High-end exposure to food and water residues are typically assumed.
    Short-term risk results from exposure to the pesticide for a period 
of 1-7 days, and therefore overlaps with the acute risk assessment. 
Historically, this risk assessment was intended to address primarily 
dermal and inhalation exposure which could result, for example, from 
residential pesticide applications. However, since enaction of FQPA, 
this assessment has been expanded to include both dietary and non-
dietary sources of exposure, and will typically consider exposure from 
food, water, and residential uses when reliable data are available. In 
this assessment, risks from average food and water exposure, and high-
end residential exposure, are aggregated. High-end exposures from all 
three sources are not typically added because of the very low 
probability of this occurring in most cases, and because the other 
conservative assumptions built into the assessment assure adequate 
protection of public health. However, for cases in which high-end 
exposure can reasonably be expected from multiple sources (e.g. 
frequent and widespread homeowner use in a specific geographical area), 
multiple high-end risks will be aggregated and presented as part of the 
comprehensive risk assessment/characterization. Since the toxicological 
endpoint considered in this assessment reflects exposure over a period 
of at least 7 days, an additional degree of conservatism is built into 
the assessment; i.e., the risk assessment nominally covers 1-7 days 
exposure,

[[Page 63237]]

and the toxicological endpoint/NOEL is selected to be adequate for at 
least 7 days of exposure. (Toxicity results at lower levels when the 
dosing duration is increased.)
    Intermediate-term risk results from exposure for 7 days to several 
months. This assessment is handled in a manner similar to the short-
term risk assessment.
    Chronic risk assessment describes risk which could result from 
several months to a lifetime of exposure. For this assessment, risks 
are aggregated considering average exposure from all sources for 
representative population subgroups including infants and children.

B. Aggregate Exposure

    In examining aggregate exposure, section 408 of the FFDCA 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, residues in 
ground water or surface water that is consumed as drinking water, and 
other non-occupational exposures through pesticide use in gardens, 
lawns, or buildings (residential and other indoor uses). 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. In evaluating food 
exposures, EPA takes into account varying consumption patterns of major 
identifiable subgroups of consumers, including infants and children. 
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% 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.

II. Aggregate Risk Assessment and Determination of Safety

    Consistent with section 408(b)(2)(D) of the FFDCA, 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 zeta-
cypermethrin and to make a determination on aggregate exposure, 
consistent with section 408(b)(2) of the FFDCA, for residues of zeta-
cypermethrin in or on cabbage at 2.0 ppm; cottonseed at 0.5 ppm; 
lettuce, head at 10.0 ppm; onions, bulb at 0.10 ppm; pecans at 0.05 
ppm; and the fat, meat, and mbyp of cattle, goats, hogs, horses, and 
sheep at 0.05 ppm. EPA's assessment of the dietary exposures and risks 
associated with establishing the tolerances follows.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its 
validity, completeness, and reliability as well as the relationship of 
the results of the studies to human risk. EPA has also considered 
available information concerning the variability of the sensitivities 
of major identifiable subgroups of consumers, including infants and 
children. The nature of the toxic effects caused by zeta-cypermethrin 
are discussed in this unit.
    1. Acute toxicity studies with technical zeta-cypermethrin: oral 
LD<INF>50</INF> in the rat is 134.4 milligram (mg)/kilogram (kg) for 
males and 86.0 mg/kg for females--Toxicity Category II.
    2. Acute toxicity studies with cypermethrin bridged to zeta-
cypermethrin: dermal LD<INF>50</INF> > 2460 mg/kg in rabbits and 
LD<INF>50</INF> > 4920 in rats--Toxicity Category III; inhalation 
(LC<INF>50</INF> 2.5 mg/liter (L) for females and > 2.5 mg/L in males--
Toxicity Category III; primary eye irritation-- not irritating--
Toxicity Category IV; primary dermal irritation, primary irritation 
score (PIS) 0.71 --Toxicity Category IV; dermal sensitization--moderate 
sensitizer in two studies, negative in other studies; delayed type 
neurotoxicity in hens--no evidence of delayed type neurotoxicity in 
hens at dose levels of 0, 2,500, 5,000, or 10,000 mg/kg; neurotoxicity 
screen in rats--NOEL and lowest-observed effect level (LOEL) 
established as < 20 mg/kg--at 20 mg/kg decreased motor activity and 
gait abnormalities.
    3. In a 90-day feeding study, rats were dosed at 0, 10, 50, 150, 
250, 500, or 900 ppm (0, 0.6, 2.7, 8.4, 13.8, 28.2, or 55.7 mg/kg/day 
for males and 0, 0.6, 3.3, 9.6, 16.3, 32.2, or 65.2 mg/kg/day for 
females). The NOEL is 250 ppm (13.9 mg/kg/day) and the LOEL is 500 ppm 
(28.2 mg/kg/day) based on decreases in bodyweight and bodyweight gains 
and food consumption at 28.2 mg/kg/day and above and deaths; clinical 
signs of neurotoxicity; decreases in erythrocyte and leukocyte counts, 
hemoglobin, and hematocrit, and increases in blood urea nitrogen (BUN) 
at 55.7 mg/kg/day.
    4. The 21-day dermal, subchronic oral study in the dog and the 21-
day inhalation studies are bridged from cypermethrin.
    In a subchronic toxicity study, dogs were dosed at 0, 5, 50, 500, 
or 1,500 ppm (corresponding to 0, 125, 1.25, 12.5, and 37.5 mg/kg/day) 
for 13 weeks. The LOEL is 1,500 ppm (37.5 mg/kg/day, based on clinical 
signs indicating neurotoxicity). The NOEL is 500 ppm (12.5 mg/kg/day).
    In a 21-day dermal toxicity study, rabbits were dosed at 2, 20, or 
200 mg/kg/day with daily applications for 3 weeks for a total of 15 
applications. Five/sex/group were abraded prior to application of the 
test material. The LOEL is 200 mg/kg/day based on liver effects. The 
NOEL is 20 mg/kg/day.
    In a 21-day subchronic inhalation toxicity study, rats were dosed 
by nose only exposure at concentrations of 0, 0.01, 0.05, or 0.25 mg/L 
for 6 hours per day, 5 days per week for a total of 15 exposures. 
Additional satellite groups of five/sex were included for recovery 
assessment and analysis of cypermethrin in the brain. The LOEL is 0.05 
mg/L based mainly on bodyweight decrease. The NOEL is 0.01 mg/L.
    5. The chronic/oncogenicity studies are bridged from cypermethrin.
    In a chronic toxicity study, dogs were dosed at 0, 1, 5, or 15 mg/
kg/day for 52 weeks. The LOEL is 5 mg/kg/day based on gastrointestinal 
effects. The NOEL is 1 mg/kg/day.
    In a carcinogenicity study, mice were dosed at control-1, control-
2, 100, 400, and 1,600 ppm (corresponding to 0, 0, 14, 57, or 229 mg/
kg/day) for 97 weeks for males and 101 weeks for females. The LOEL is 
400 ppm (57 mg/kg/day) based on liver weight. The NOEL is 100 ppm (14 
mg/kg/day). This study was determined to be positive for induction of 
benign alveologenic neoplasms. Adequacy of dosing for carcinogenicity 
is based upon typically 9% decreases in males and 12% in females in the 
first months of the study.
    In a chronic toxicity/carcinogenicity study, rats were dosed at 
control-1, control-2, 20, 150, or 1,500 ppm (corresponding to 0, 0, 1, 
7.5, or 75 mg/kg/day) for 2 years. Satellite groups of 12/sex were 
sacrificed after 1 year of dosing. The LOEL is 1,500 ppm (75 mg/kg/day) 
based on bodyweight. The NOEL is 150 ppm (7.5 mg/kg/day). Cypermethrin 
was not considered to be

[[Page 63238]]

oncogenic in this study. A possible association with increased 
testicular interstitial tumors was not considered definite.
    6. Zeta-cypermethrin was tested in a developmental toxicity study 
in rats at the following dose levels: 0, 5, 12, 25, or 35 mg/kg/day. 
Groups of 25 females were administered the test chemical by gavage on 
gestation days 6 through 15 in a volume of 5 milliliter (ml)/kg 
bodyweight. No developmental toxicity was observed at any dose level. 
The maternal NOEL is 12.5 mg/kg and the maternal LOEL is 25 mg/kg based 
on decreases in bodyweight and bodyweight gain and food consumption and 
clinical signs of toxicity, particularly neurotoxicity. The 
developmental NOEL is 35 mg/kg/day highest dose tested (HDT). The LOEL 
was not established.
    7. The developmental toxicity study in the rabbit is bridged from 
cypermethrin.
    In a developmental toxicity study, rabbits were dosed at 0 (empty 
capsule), 0 (capsule plus corn oil), 3, 10, or 30 mg/kg/day on days 6 
to 18 inclusive of gestation. There were no effects of any kind 
reported on the does. The maternal LOEL is > 30 mg/kg/day. The maternal 
NOEL is > 30 mg/kg/day. There were no treatment related effects on 
either the skeletal or visceral structures reported. The developmental 
LOEL is > 30 mg/kg/day. The developmental NOEL is > 30 mg/kg/day.
    In a developmental toxicity study, rabbits were dosed at 0, 100, 
450, or 700 mg/kg/day from days 7 through 19 of gestation. The does 
were sacrificed on day 29 of gestation. The maternal LOEL is 450 mg/kg/
day, based on bodyweight gain. The maternal NOEL is 100 mg/kg/day. 
There were no indications of developmental toxicity. The NOEL and LOEL 
for developmental toxicity is > 700 mg/kg/day.
    8. Zeta-cypermethrin was tested in a two-generation reproduction 
study in groups of 30 male and 30 female rats at the following dose 
levels: 0, 7.5, 25, 100, 375, or 750 ppm (0, 0.5, 1.8, 7, 27, or 45 mg/
kg/day). The parental and reproductive NOELs are 7 mg/kg/day and LOELs 
are 27 mg/kg/day based on decreased parental and pup weight, 
particularly during lactation, clinical signs of toxicity, and death at 
45 mg/kg/day.
    9. Zeta-cypermethrin was tested in a reverse mutation assay in 
salmonella typhimurium strains TA1535, TA1537, TA100, TA1538, and TA98 
at 0, 100, 333, 1,000, 3,333, 5,000, or 10,000 microgram (<greek-m>g)/
plate. It gave a very weak positive response (two-fold increase in 
revertants/plate) in strain TA100 at 10,000 <greek-m>g/plate without S-
9 activation in two-separate experiments. Doses of 3,333 and 5,000 
<greek-m>g/plate gave 1.5 and 1.6-fold increases in revertants/plate, 
respectively. Strains TA98, TA1535, TA1537, and TA1538 treated in the 
presence and absence of mammalian S-9 activation were not affected. 
Zeta-cypermethrin is therefore considered a possible weak mutagen under 
the conditions of the assay.
    10. Zeta-cypermethrin was tested in an in vitro mammalian cell gene 
mutation assay in Chinese hamster ovary (CHO) cells (CHO-K<INF>1</INF>-
BH<INF>4</INF>, subclone D<INF>1</INF>) at the following dose levels: 
0, 1, 10, 25, 50, 100, 400, 700, or 1,000 <greek-m>g/ml, both in the 
absence and presence of S-9 activation. No evidence of increased 
forward mutation rate at the hypoxanthine guanine phosphoribose 
transferase (HGPRT) locus was observed at any dose tested under the 
conditions of these assays. The solubility limit of the test compound 
in culture media was approximately 100 <greek-m>g/ml.
    11. Zeta-cypermethrin was tested in an in vivo rat bone marrow 
chromosomal aberration assay. Groups of 15 male and 15 female Sprague-
Dawley rats were administered single doses by gavage with 0, 31.25, 
62.5, or 125 mg/kg zeta-cypermethrin in corn oil. Five rats/sex were 
sacrificed at 6, 18, and 30 hours-post dosing. Cyclophosphamide was 
used as the positive control (60 mg/kg). No evidence of structural 
chromosomal aberrations was demonstrated at either 6, 18, or 30 hours-
post dosing.
    12. Zeta-cypermethrin was tested in an unscheduled deoxyribonucleic 
acid (DNA) synthesis assay in male Fischer 344 rat primary hepatocyte 
cells. The dose levels tested were 0, 14, 45, 140, 450, 1,400, or 4,500 
<greek-m>g/ml. No unscheduled DNA synthesis was observed at any dose 
level up to 4,500 <greek-m>g/ml in the primary hepatocyte cultures 
under the conditions of the assay. Minimal cytotoxicity was observed at 
the highest doses. Incomplete solubility of the test compound in 
culture media was observed, particularly at the higher doses. The 
positive control gave clear positive responses. The study is acceptable 
for regulatory purposes.
    13. The metabolism studies are bridged from cypermethrin.
    Several studies with both rats, dogs, and mice are available to 
support the requirement for metabolism in mammals. Some of these 
studies assess individual cis- and trans-radiolabeled isomers and other 
studies assess the metabolism of cypermethrin with the label in either 
the cyclopropyl of the phenoxybenzyl ring. In general the following has 
been demonstrated from these studies:
    Cypermethrin is readily absorbed from the gastrointestinal tract 
and extensively metabolized. It is mostly excreted in the urine and 
contains several characterized metabolites derived from conjugation of 
the hydrolysis products of the parent compound following cleavage of 
the esteratic linkage site. The following three executive summaries 
describe the metabolism of cypermethrin in rats.
    First study--First group. Six/sex rats, Wistar strain rats, were 
dosed with a single dose 0.61 mg/animal of labeled cis-cypermethrin 
isomers in 0.5 ml of corn oil. The rats were individually housed in 
metabolism cages and their urine and fecal matter collected daily until 
sacrifice. Two rats of each sex were sacrificed after 24 and 72 hours 
and after 8 days. Samples of the blood and selected tissues were 
assessed for radioactivity content.
    Second group. Three/sex rats were dosed with 0.615 mg/animal of 
labeled trans-cypermethrin in 0.8 ml of corn oil. In addition to the 
urine and fecal collections, expired air was also collected from one 
male and one female. Total recovery was from 97.2% to 100.5%. About 70% 
of cis- and 80% of trans-cypermethrin was excreted in 24 hours. 
Essentially all was excreted in 8 days. Most of the label was excreted 
in the urine (> 53%) with less in the feces and (< 20%) for the trans 
(males and females) and cis (males only) groups and < 1% in the air for 
all groups. A sex difference with respect to excretion in the urine 
from the cis-isomer was noted for females since about equal amounts 
(35%) were found in both the urine and feces. Several urinary and fecal 
metabolites were tentatively characterized.
    Second study. One group of three/sex Wistar strain rats was dosed 
with a single-oral dose (approximately 1.3 mg/kg) of 14C-cyclopropyl 
labeled cypermethrin in corn oil (0.8 ml). The rats were then placed in 
glass metabolism cages and their urine and feces were collected. 
Special metabolism cages for trapping any radioactivity expired through 
their respiratory system were used for one male and one female rat. The 
rats were sacrificed after 3 days and their blood and selected tissues 
were assessed for radioactivity, 85.5% for males and 97.2% for females 
of 14C was excreted in 72 hours. The urine (55.8% for males and 69.4% 
for females) was the major route of excretion with the feces containing 
the balance. The air contained only 0.1% or less. Tissue

[[Page 63239]]

retention was highest in the skin (1.2%) and liver (0.74% for males but 
only 0.18% for females) and fat (0.57 to 0.66%).
    Third study. In a series of nine different studies, labeled 
cypermethrin (1 mg/kg or less) in corn oil or separated cis- or trans-
cypermethrin isomers were given by gavage to single or groups of two or 
three Wistar strain rats. Their urine and in some cases fecal matter 
was collected at various intervals such as 18 hours to 3 days. In 
another set of experiments, labeled cypermethrin was administered to 
rats that were fitted with bile duct cannalulas and their bile 
collected for 4-5 hours while the rat was under anesthesia. Cis- and 
trans-14C-cyclopropyl labeled cypermethrin was demonstrated to form 
glucuronide conjugations of cis- and trans-acids and hydroxyacids. Only 
1.6% or less of the total dose is excreted in the bile. Most of the 
cypermethrin in the feces was unmetabolized. The glucuronide conjugates 
in the urine were found to be unstable and subject to hydrolysis.
    14. Acute delayed type neurotoxicity-hens. Cypermethrin was tested 
in the hen following a protocol similar to the series 81-7 guideline. 
The dose levels tested were 0, 2,500, 5,000, and 10,000 mg/kg but there 
was no indication of the delayed type neurotoxicity noted.
    15. Acute neurotoxicity screen-rats. There are two acute 
neurotoxicity studies with cypermethrin.
    First study. Rats were dosed with cypermethrin at dose levels of 0, 
20, 60, or 120/100 mg/kg. The rats displayed gait, muscle effects, and 
choreoathetosis. Motor activity was decreased for all dose groups for 
males (estimated 45%, 66%, and 85% for the 20, 60, and 100 mg/kg dose 
group respectively) and gait abnormalities were present in the low-dose 
group. Body temperature was increased about 1  deg.C in the low-dose 
male group but decreased for the higher groups. Some 10 other 
parameters were affected at 60 mg/kg and/or above. These included: 
Salivation, urination, arousal, abnormal motor movement, forelimb, or 
hindlimb grip strength, landing foot splay, touch response, and tail 
pinch response. The LOEL and NOELs for neurotoxicity are < 20 mg/kg. At 
20 mg/kg decreased motor activity and gait abnormalities resulted.
    Second study. Rats were dosed with cypermethrin in corn oil as 
control, 30, 100, or 200 mg/kg. The rats were assessed at pretest, 4 
hours after treatment and on days 7 and 14 for Functional Observational 
Battery (FOB) and motor activity. After day 14, five/sex were prepared 
for neurohistopathology. At 100 mg/kg, ataxia (two males and two 
females) and related conditions (staggered or impaired gait, decreased 
activity, splayed hindlimbs, and limp condition) and decreased motor 
activity (49%, p < 0.001 for males and 33%, p < 0.01 for females) 
resulted. In addition, some females had salivation, lacrimation and/or 
soiled fur. At 200 mg/kg, deaths resulted (one male and two females) as 
well as several other parameters being affected. The LEL is 100 mg/kg 
based primarily on ataxia and related conditions. The NOEL is 30 mg/kg.
    The first study in Unit II. A.15. of this preamble is considered to 
define the neurotoxicity to cypermethrin because responses were noted 
at lower-dose levels. The second study used a variable and large dose 
of corn oil and a different strain of rat.
    16. Subchronic neurotoxicity screen in rats. Rats were dosed with 
cypermethrin as control, 500, 1,300 or 1,700 ppm (31, 77, or 102 for 
males and 37, 95, or 121 for females mg/kg/day) for 90 days in a 
subchronic neurotoxicity study. At 1,300 ppm, females displayed ataxia 
(1/10), splayed hindlimbs (5/16), impaired gait (4/10), and decreased 
feces (4/10) as well as decreased bodyweight gain (<difference>41%). 
Males had only decreased bodyweight gain (<difference>27%) and 
increased landing foot splay. At 1,700 ppm, males showed ataxia (8/10) 
and additional related symptoms and females had decreased motor 
activity (<difference>27%). The LEL is 1,300 ppm (77 mg/kg/day) based 
on several effects. The NOEL is 500 ppm (31 mg/kg/day).
    Because the studies in Units II. A.15. and 16. of this preamble are 
screens, neurotoxicity studies will be required under a special Data 
Call-In (DCI) letter pursuant to section 3(c)(2)(B) of FIFRA. Although 
these data are lacking, EPA has sufficient toxicity data base to 
support these tolerances and these additional studies are not expected 
to significantly change its risk assessment.

B. Toxicological Endpoints

    1. Acute toxicity. For acute dietary risk assessment, EPA 
recommends use of a NOEL of 0.5 mg/kg/day based on the NOEL of 1.0 mg/
kg/day from the cypermethrin chronic toxicity study in dogs and a 
correction factor of two to account for the differences in the 
percentage of the biologically active isomer. The LOEL of this study of 
5.0 mg/kg/day was based on gastrointestinal disturbances observed in 
the first week of the study.
    2. Short- and intermediate-term toxicity. For short- and 
intermediate-term MOE's, EPA recommends use of a NOEL of 2.5 mg/kg/day 
based on neurotoxic signs in dogs starting at week 1. The inhalation 
NOEL is 5.0 with a correction factor of 2. Dermal absorption rate was 
25%. A dermal absorption rate of 25% was recommended based on the 
weight-of-the-evidence available for structurally related pyrethroids.
    3. Chronic toxicity. EPA has established the RfD for zeta-
cypermethrin at 0.005 mg/kg/day. This RfD is based on gastrointestinal 
disturbances in dogs with an uncertainty factor of 200 to account for 
differences in percent biologically active isomers in enriched product.
    Since insufficient data on zeta-cypermethrin are available to 
establish an RfD, the data from cypermethrin were used in establishing 
an RfD for zeta-cypermethrin. The NOELs from the cypermethrin studies 
were divided by 2 as a correction factor, assuming the worst case that 
the biologically active isomers are the ones which carry most of the 
toxicity. The following paragraph summarizes the decision logic for 
establishing the RfD for zeta-cypermethrin from the cypermethrin data 
base.
    In general, the most sensitive species for the 10 synthetic 
pyrethroids appears to be the dog. For zeta-cypermethrin the Agency 
does not have any toxicity data on the dog that can be compared with 
the dog studies conducted with cypermethrin. In addition, the Agency 
also does not have any chronic studies on zeta-cypermethrin that can be 
compared with those conducted with cypermethrin. Therefore, although a 
comparison of the LEL's from the zeta-cypermethrin studies with the 
corresponding LEL's from the cypermethrin studies does not show a 
pronounced difference in toxicity, for risk assessment purposes, the 
Agency has decided to use the toxicity endpoints from cypermethrin with 
a two-fold correction factor to account for the differences in the 
percentages of the more biologically active isomers in the enriched 
technical product (zeta-cypermethrin). This would also apply to the 
inhalation endpoint because the Agency has no inhalation studies with 
zeta-cypermethrin. The Agency is making a conservative assumption that 
most of the toxicity for cypermethrin will be from the four more 
biologically active isomers of zeta-cypermethrin. Based on previous 
documentation, the Agency is assuming that the percentages of the 
isomers are approximately as follows:
    Cypermethrin, eight isomers with percentage compositions ranging 
from 11-14% and zeta-cypermethrin, eight isomers with four 
insecticidally less active ones at a concentration of 1% each. The 
remaining four isomers, two

[[Page 63240]]

of which are regarded as being the most insecticidally active, will be 
present at a concentration of 24% each.
    4. Carcinogenicity. No carcinogenicity studies are available for 
zeta-cypermethrin. Using its Guidelines for Carcinogen Risk Assessment 
published September 24, 1986 (51 FR 33992) the Carcinogenicity Peer 
Review Committee (CPRC) has classified cypermethrin as a weak Group C 
(possible human carcinogen) based on the increased incidence in lung 
adenomas in female CD-1 mice, but did not recommend assignment of a 
cancer potency factor (Q*1) for a linear quantitative cancer risk 
assessment. An RfD approach was recommended for human risk assessment 
purposes. It is assumed that zeta-cypermethrin would also test 
positively for lung adenomas in female CD-1 mice.

C. Exposures and Risks

    1. From food and feed uses. Tolerances have been established (40 
CFR 180.418) for the residues of zeta-cypermethrin in or on a variety 
of raw agricultural commodities. Tolerances range from 0.05 ppm in 
animal commodities to 10.0 ppm in head lettuce. Registered uses include 
cabbage, cotton, head lettuce, onions, and pecans. Risk assessments 
were conducted by EPA to assess dietary exposures and risks from zeta-
cypermethrin as follows:
    i. Acute exposure and risk. Acute dietary risk assessments are 
performed for a food-use pesticide if a toxicological study has 
indicated the possibility of an effect of concern occurring as a result 
of a 1 day or single exposure. The acute dietary exposure assessment 
used Monte Carlo modeling incorporating anticipated residues and 
percent crop treated refinements. The acute dietary MOE at the 99.9th 
percentile for the overall U.S. population is 126. The MOE at the 
99.9th percentile for children 1-6 years of age is 105. EPA concludes 
that there is a reasonable certainty of no harm for MOEs of 100 or 
greater. Therefore, the acute dietary risk assessment for zeta-
cypermethrin indicates a reasonable certainty of no harm.
    ii. Chronic exposure and risk. The RfD used for the chronic dietary 
analysis is 0.005 mg/kg/day based on a NOEL of 1.0 mg/kg/day from the 
cypermethrin chronic dog study and an uncertainty factor of 200 (used 
to account for the differences in the percentage of the biologically 
active isomer). The endpoint effect of concern was based on 
gastrointestinal disturbances observed in the first week of the study 
at the LOEL of 5.0 mg/kg/day. The chronic dietary exposure assessment 
used anticipated residues, monitoring data, and percent of crop treated 
information . The chronic dietary exposure estimate for the overall 
U.S. population was calculated to be 0.000018 mg/kg/day (0.4% RfD 
utilized) and for children 1-6 years was calculated to be 0.00027 mg/
kg/day (0.5% RfD utilized).
    EPA notes that the acute dietary risk assessments used Monte Carlo 
modeling (in accordance with Tier 3 of EPA June 1996 ``Acute Dietary 
Exposure Assessment'' guidance document) incorporating anticipated 
residues and percent of crop treated refinements. The chronic dietary 
risk assessments used anticipated residues and percent crop treated 
information.
    Section 408(b)(2)(E) authorizes EPA to consider 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 timeframe it 
deems appropriate. Section 408(b)(2)(F) allows the Agency to use data 
on the actual percent of crop treated when establishing a tolerance 
only where the Agency can make the following findings:
    a. That the data used are reliable and provide a valid basis for 
showing the percentage of food derived from a crop that is likely to 
contain residues.
    b. That the exposure estimate does not underestimate the exposure 
for any significant subpopulation.
    c. Where data on regional pesticide use and food consumption are 
available, that the exposure estimate does not understate exposure for 
any regional population.
In addition, the Agency must provide for periodic evaluation of any 
estimates used.
    The percent of crop treated estimates for zeta-cypermethrin were 
derived from Federal and market survey data. EPA considers these data 
reliable. A range of estimates are supplied by this data and the upper 
end of this range was used for the exposure assessment. By using this 
upper-end estimate of percent crop treated, the Agency is reasonably 
certain that exposure is not underestimated for any significant 
subpopulation. 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. Review 
of this regional data allows the Agency to be reasonably certain that 
no regional population is exposed to residue levels higher than those 
estimated by the Agency. To meet the requirement for data on 
anticipated residues, EPA will issue a DCI notice pursuant to FFDCA 
section 408(f) requiring submission of data on anticipated residues in 
conjunction with approval of the registration under the FIFRA.
    2. From drinking water. Laboratory and field data have demonstrated 
that cypermethrin is immobile in soil and will not leach into ground 
water. Estimates of zeta-cypermethrin drinking water concentrations 
were generated with the PRZM1 and EXAMS computer models. Based on these 
analyses, the contribution of water to the dietary risk estimate is 
negligible. Therefore, EPA concludes that together these data indicate 
that residues are not expected to occur in drinking water.
    i. Acute exposure and risk. The acute drinking water exposure and 
risk estimates are 0.000126 mg/kg/day (MOE of 3,982) and 0.000242 mg/
kg/day (MOE of 2,069) for the overall U.S. population and non-nursing 
infants < 1 year old, respectively.
    ii. Chronic exposure and risk. The chronic drinking water exposure 
and risk estimates are 0.000005 mg/kg/day (0.1% of RfD utilized) and 
0.000021 mg/kg/day (0.4% of RfD utilized) for the overall U.S. 
population and non-nursing infants < 1 year old, respectively.
    3. From non-occupational non-dietary exposure. Zeta-cypermethrin is 
registered for agricultural crop applications only; therefore, no non-
occupational, non-dietary exposure is expected.
    4. Cumulative exposure to substances with common mechanism of 
toxicity. Section 408(b)(2)(D)(v) of the FFDCA 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

[[Page 63241]]

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).
    Four members of the insecticide class pyrethroids produce a common 
metabolite known as DCVA (3-(2,2-dichloroethenyl)-2,2-
dimethylcyclopropane carboxylic acid). These insecticides are 
cyfluthrin, cypermethrin, zeta-cypermethrin, and permethrin. Although 
the residues of DCVA can be estimated, no toxicology data on the 
compound per se are available to directly conduct a hazard evaluation 
and thereby establish an appropriate endpoint for use in a joint risk 
assessment. To date, for the purpose of assessing the risk of the 
parent compound, the toxicity of the DCVA has been assumed to be 
equivalent to the parent compound. However, due to the markedly 
different toxicological profiles of cyfluthrin, cypermethrin, zeta-
cypermethrin, and permethrin, EPA does not believe that it would be 
appropriate to cumulate DCVA residues from these pesticides, or DCVA 
residues from one of these pesticides with the parent of another of 
these pesticides, in conducting the risk assessment for these 
pesticides.
    Accordingly, EPA does not have, at this time, available data to 
determine whether zeta-cypermethrin 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 zeta-cypermethrin has a common mechanism of 
toxicity with other substances.

D. Aggregate Risks and Determination of Safety for U.S. Population

    1. Acute risk. The acute aggregate risk assessment takes into 
account exposure from food and water. The MOE calculated at the 99.9th 
percentile for the overall U.S. population is 122. The Agency has no 
cause for concern if total acute exposure calculated for the 99.9th 
percentile yields a MOE of 100 or larger. Therefore, the Agency has no 
acute aggregate concern due to exposure to zeta-cypermethrin through 
food and drinking water.
    2. Chronic risk. Using the Anticipated Residue Contribution (ARC) 
exposure assumptions, EPA has concluded that aggregate exposure to 
zeta-cypermethrin from food and water will utilize 0.5% of the RfD for 
the U.S. population. The major identifiable subgroup with the highest-
aggregate exposure is children, ages 1-6 years old, discussed in Unit 
II. F. of this preamble. EPA generally has no concern for exposures 
below 100% of the RfD because the RfD represents the level at or below 
which daily aggregate dietary exposure over a lifetime will not pose 
appreciable risks to human health. EPA concludes that there is a 
reasonable certainty that no harm will result from aggregate exposure 
to zeta-cypermethrin residues.
    3. Short- and intermediate-term risk. Short- and intermediate-term 
aggregate exposure takes into account chronic dietary food and water 
(considered to be a background exposure level) plus indoor and outdoor 
residential exposure. Based on zeta-cypermethrin not being registered 
for residential non-food sites, EPA concludes that the aggregate short- 
and intermediate-term risks do not exceed levels of concern (MOE less 
than 100), and that there is reasonable certainty that no harm will 
result from aggregate exposure to zeta-cypermethrin residues.

E. Aggregate Cancer Risk for U.S. Population

    No carcinogenicity studies are available for zeta-cypermethrin. 
However, cypermethrin has been classified as a weak Group C carcinogen 
with no Q*1 based on the increased incidence in lung adenomas in female 
CD-1 mice. Based on the recommendation that the RfD approach be used, a 
quantitative dietary cancer risk assessment was not performed. Dietary 
risk concerns due to long-term consumption of cypermethrin are 
adequately addressed by the DRES chronic exposure analysis using the 
RfD. For the U.S. population, less than 1% of the RfD is occupied by 
aggregate chronic food and water exposure.

F. Aggregate Risks and Determination of Safety for Infants and Children

    1. Safety factor for infants and children--i. In general. In 
assessing the potential for additional sensitivity of infants and 
children to residues of zeta-cypermethrin, EPA considered data from 
developmental toxicity studies in the rat and rabbit and a two-
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 one or both parents. Reproduction studies provide information 
relating to effects from exposure to the pesticide on the reproductive 
capability of mating animals and data on systemic toxicity.
    Section 408 of the FFDCA provides that EPA shall apply an 
additional 10-fold 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 data base unless EPA determines that a 
different margin of safety will be safe for infants and children. 
Margins of safety are incorporated into EPA risk assessments either 
directly through use of a MOE analysis or through using uncertainty 
(safety) factors in calculating a dose level that poses no appreciable 
risk to humans. EPA believes that reliable data support using the 
standard MOE and uncertainty factor (usually 100 for combined inter- 
and intra-species variability) and not the additional 10-fold MOE/
uncertainty factor when EPA has a complete data base under existing 
guidelines and when the severity of the effect in infants or children 
or the potency or unusual toxic properties of a compound do not raise 
concerns regarding the adequacy of the standard MOE/safety factor.
    ii. Developmental toxicity studies. In a prenatal developmental 
toxicity study in rats, there was no evidence of developmental toxicity 
at the HDT (35 mg/kg/day). Maternal toxicity (ataxia, urine and feces 
stained fur, decreased bodyweight gain and food consumption) was 
observed at the maternal LOEL (25 mg/kg/day), and the maternal NOEL was 
established at 12.5 mg/kg/day. In

[[Page 63242]]

addition, an acceptable prenatal developmental toxicity study in 
rabbits conducted with cypermethrin was submitted.
    iii. Reproductive toxicity study. In the two-generation 
reproduction study in rats, offspring toxicity (decreased pup weight 
gain during lactation) was observed at the same treatment level which 
resulted in parental systemic toxicity (NOEL = 100 ppm or 27 mg/kg/day; 
LOEL = 375 ppm or 45 mg/kg/day).
    iv. Pre- and post-natal sensitivity. There is no evidence of 
additional sensitivity to young rats following pre- or post-natal 
exposure to zeta-cypermethrin.
    v. Conclusion. The data base related to pre- and post-natal 
sensitivity is complete. Based on the information in Unit II. F. of 
this preamble, 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.
    2. Acute risk. The acute aggregate risk assessment takes into 
account exposure from food and water. The MOE calculated at the 99.9th 
percentile for children age 1-6 is 102. The Agency has no cause for 
concern if total acute exposure calculated for the 99.9th percentile 
yields an MOE of 100 or larger. Therefore, the Agency has no acute 
aggregate concern due to exposure to zeta-cypermethrin through food and 
drinking water.
    3. Chronic risk. Using conservative exposure assumptions, EPA has 
concluded that aggregate exposure to zeta-cypermethrin from food and 
water will utilize 0.6% of the RfD for children, ages 1-6 years old. 
EPA generally has no concern for exposures below 100% of the RfD 
because the RfD represents the level at or below which daily aggregate 
dietary exposure over a lifetime will not pose appreciable risks to 
human health. EPA concludes that there is a reasonable certainty that 
no harm will result to infants and children from aggregate exposure to 
zeta-cypermethrin residues.
    4. Short- or intermediate-term risk. Based on zeta-cypermethrin not 
being registered for residential non-food sites, EPA concludes that the 
aggregate short- and intermediate-term risks do not exceed levels of 
concern, and that there is reasonable certainty that no harm will 
result.
    5. Special docket. The complete acute and chronic exposure analyses 
(including dietary, non-dietary, drinking water, and residential 
exposure, and analysis of exposure to infants and children) used for 
risk assessment purposes can be found in the Special Docket for the 
FQPA under the title ``Risk Assessment for Extension of Tolerances for 
Synthetic Pyrethroids.'' Further explanation regarding EPA's decision 
regarding the additional safety factor can also be found in the Special 
Docket.

G. Endocrine Disrupter Effects

    EPA is required to develop a screening program to determine whether 
certain substances (including all pesticides and inerts) ``may have an 
effect in humans that is similar to an effect produced by a naturally 
occurring estrogen, or such other endocrine effect....'' The Agency is 
currently working with interested stakeholders, including other 
government agencies, public interest groups, industry, and research 
scientists in developing a screening and testing program and a priority 
setting scheme to implement this program. Congress has allowed 3 years 
from the passage of FQPA (August 3, 1999) to implement this program. At 
that time, EPA may require further testing of this active ingredient 
and end use products for endocrine disrupter effects.

III. Other Considerations

A. Metabolism In Plants and Animals

    The metabolites found in plants and livestock also are formed in 
the rat. It was concluded that 3-phenoxybenzoic acid (PBA) and its 
conjugates are not of concern based on toxicology data for PBA. In the 
absence of toxicology data, the cis- and trans-isomers of DCVA are 
considered to be of comparable toxicity to the parent. In light of 
Codex Maximum Residue Limits (MRLs) including only the parent compound, 
the parent being recoverable by the Food and Drug Administration (FDA) 
multi-residue Methods I and II, and the DCVA is not likely to be 
measured by these methods, it was concluded that tolerances should be 
set in terms of cypermethrin only. Crop field trials should continue to 
include analyses for residues of cis- and trans-DCVA.

B. Analytical Enforcement Methodology

    Adequate enforcement methodology Gas Chromatography/Electron 
Capture Detector (GC/ECD) is available in Pesticide Analytical Method 
II (PAM II) as Method I to enforce the tolerance expression.

C. Magnitude of Residues

    Residue data from field trials and the FDA monitoring program 
(1992-1995) and the PDP monitoring program (1994) were used to estimate 
chronic dietary exposure. For the chronic analyses, mean residues from 
FDA monitoring were used for lettuce and onions (dry bulb). Residue 
field trial data were used for broccoli, cabbage, cotton, green onions, 
mustard greens, and pecans.
    For acute dietary exposure analysis, field trial residue data, 
along with percent of crop treated data, were used in the Monte Carlo 
analysis.

D. International Residue Limits

    Codex MRLs for cypermethrin have been established which are in 
harmony with the U.S. tolerances for meat and mbyp of cattle, goats, 
hogs, horses, and sheep (0.05 ppm); milk (0.05 ppm); and onions, bulb 
(0.10 ppm).
    Codex MRLs have been established which exceed the U.S. tolerances 
for meat (fat basis) of cattle, goats, hogs, horses, and sheep (0.2 vs. 
0.05 ppm).
    Codex MRLs have been established which are below their U.S. 
counterparts for cabbage (brassica vegetables) (1.0 vs. 2.0 ppm) and 
lettuce, head (2.0 vs. 10.0 ppm).
    No Canadian MRLs have been established for residues of 
cypermethrin.
    Mexico has established a tolerance for residues of cypermethrin on 
cottonseed (0.5 ppm) which is in harmony with the U.S. tolerance.
    As indicated in this unit, there are differences between the FFDCA 
section 408 tolerances and the Codex MRL values for specific 
commodities. These differences could be caused by differences in 
methods to establish tolerances, calculations of animal feed dietary 
exposure, and as a result of different agricultural practices. EPA will 
specifically address these differences when the pesticides are 
reregistered and the tolerances made permanent.

IV. Conclusion

    Therefore, the tolerances are established for residues of zeta-
cypermethrin (s-cyano(3-phenoxyphenyl) methyl (<plus-minus>) cis, trans 
3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate) in or on 
cabbage at 2.0 ppm; cottonseed at 0.5 ppm; lettuce, head at 10.0 ppm; 
onions, bulb at 0.10 ppm; pecans at 0.05 ppm; and fat, meat, and mbyp 
of cattle, goats, hogs, horses, and sheep at 0.05 ppm.

V. Objections and Hearing Requests

    The new section 408(g) of the FFDCA provides essentially the same 
process for persons to ``object'' to a tolerance regulation issued by 
EPA under new section 408(e) and (l)(6) of the FFDCA as was provided in 
the old section 408 and in section 409 of the FFDCA. However, the 
period for filing objections is 60 days, rather than 30 days. EPA 
currently has procedural regulations

[[Page 63243]]

which govern 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 those procedural regulations with appropriate adjustments to 
reflect the new law.
    Any person may, by January 26, 1998 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.

VI. Public Record and Electronic Submissions

    The official record for this rulemaking, as well as the public 
version, has been established for this rulemaking under docket control 
number OPP-300577 (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 the paper record maintained at the 
Virginia address in ``ADDRESSES'' at the beginning of this document.
    Electronic comments may be sent directly to EPA at:
    <a href="/cdn-cgi/l/email-protection#cda2bdbde0a9a2aea6a8b98da8bdaca0aca4a1e3a8bdace3aaa2bb"><span class="__cf_email__" data-cfemail="315e41411c555e525a5445715441505c50585d1f5441501f565e47">[email protected]</span></a>.


    Electronic objections and hearing requests must be submitted as an 
ASCII file avoiding the use of special characters and any form of 
encryption. Objections and hearing requests will also be accepted on 
disks in WordPerfect 5.1/6.1 or ASCII file format. All copies of 
objections and hearing requests in electronic form must be identified 
by the docket control number, OPP-300577. No 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.

VII. Regulatory Assessment Requirements

    This final rule establishes tolerances under section 408(d) of the 
FFDCA in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled Regulatory Planning and 
Review (58 FR 51735, October 4, 1993). This final rule does not contain 
any information collections subject to OMB approval under the Paperwork 
Reduction Act (PRA), 44 U.S.C. 3501 et seq., or impose any enforceable 
duty or contain any unfunded mandate as described under Title II of the 
Unfunded Mandates Reform Act of 1995 (UMRA)(Pub. L. 104-4). Nor does it 
require any prior consultation as specified by Executive Order 12875, 
entitled Enhancing the Intergovernmental Partnership (58 FR 58093, 
October 28, 1993), or special considerations as required by Executive 
Order 12898, entitled Federal Actions to Address Environmental Justice 
in Minority Populations and Low-Income Populations (59 FR7 629, 
February 16, 1994), or require OMB review in accordance with Executive 
Order 13045, entitled Protection of Children from Environmental Health 
Risks and Safety Risks (62 FR 19885, April 23, 1997).
    In addition, since these tolerances and exemptions that are 
established on the basis of a petition under section 408(d) of the 
FFDCA, such as the tolerances in this final rule, do not require the 
issuance of a proposed rule, the requirements of the Regulatory 
Flexibility Act (RFA) (5 U.S.C. 601 et seq.) do not apply. 
Nevertheless, the Agency has previously assessed whether establishing 
tolerances, exemptions from tolerances, raising tolerance levels or 
expanding exemptions might adversely impact small entities and 
concluded, as a generic matter, that there is no adverse economic 
impact. The factual basis for the Agency's generic certification for 
tolerance actions published on May 4, 1981 (46 FR 24950) and was 
provided to the Chief Counsel for Advocacy of the Small Business 
Administration.

VIII. Submission to Congress and the General Accounting Office

    Under 5 U.S.C. 801(a)(1)(A), as added by the Small Business 
Regulatory Enforcement Fairness Act of 1996, the Agency has 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 this rule in 
today's Federal Register. This 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: November 14, 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 citation for part 180 continues to read as 
follows:

    Authority: 21 U.S.C. 346a and 371.


    2. Section 180.418 is amended by adding a new paragraph (a)(2) to 
read as follows:


Sec. 180.418  Cypermethrin and an isomer zeta-cypermethrin; tolerances 
for residues.

    (a)         *        *        *
    (2) Tolerances are established for residues of the insecticide 
zeta-cypermethrin (s-cyano(3-phenoxyphenyl) methyl (<plus-minus>) cis, 
trans 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate) in 
or on the following commodities:

[[Page 63244]]



                                                                        
------------------------------------------------------------------------
                   Commodity                        Parts per million   
------------------------------------------------------------------------
Cabbage........................................                      2.0
Cattle, fat....................................                     0.05
Cattle, mbyp...................................                     0.05
Cattle, meat...................................                     0.05
Cottonseed.....................................                      0.5
Goats, fat.....................................                     0.05
Goats, mbyp....................................                     0.05
Goats, meat....................................                     0.05
Hogs, fat......................................                     0.05
Hogs, mbyp.....................................                     0.05
Hogs, meat.....................................                     0.05
Horses, fat....................................                     0.05
Horses, mbyp...................................                     0.05
Horses, meat...................................                     0.05
Lettuce, head..................................                     10.0
Milk...........................................                     0.05
Onions, bulb...................................                     0.10
Pecans.........................................                     0.05
Sheep, fat.....................................                     0.05
Sheep, mbyp....................................                     0.05
Sheep, meat....................................                     0.05
------------------------------------------------------------------------

* * * * *

[FR Doc. 97-30938 Filed 11-25-97; 8:45 am]
BILLING CODE 6560-50-F


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