[Federal Register Volume 65, Number 41 (Wednesday, March 1, 2000)]
[Notices]
[Pages 11052-11057]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-4791]


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ENVIRONMENTAL PROTECTION AGENCY

[PF-916; FRL-6489-9]


Notice of Filing a Pesticide Petition to Establish a Tolerance 
for Certain Pesticide Chemicals in or on Food

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: This notice announces the initial filing of pesticide 
petitions proposing the establishment of regulations for residues of 
certain pesticide chemicals in or on various food commodities.

DATES: Comments, identified by docket control number PF-916, must be 
received on or before March 31, 2000.

ADDRESSES: Comments may be submitted by mail, electronically, or in 
person. Please follow the detailed instructions for each method as 
provided in Unit I.C. of the SUPPLEMENTARY INFORMATION. To ensure 
proper receipt by EPA, it is imperative that you identify docket 
control number PF-916 in the subject line on the first page of your 
response.

FOR FURTHER INFORMATION CONTACT:  By mail: Tracy Keigwin, Registration 
Support Branch, Registration Division (7505), Office of Pesticide 
Programs, Environmental Protection Agency, Ariel Rios Bldg., 1200 
Pennsylvania Ave., NW., Washington, DC 20460; telephone number: (703) 
305-6605; e-mail address: [email protected].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

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

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

    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in the table could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether or not this action might apply to certain entities. If you have 
questions regarding the applicability of this action to a particular 
entity, consult the person listed under ``FOR FURTHER INFORMATION 
CONTACT.''

B. How Can I Get Additional Information, Including Copies of this 
Document and Other Related Documents?

    1. Electronically. You may obtain electronic copies of this 
document, and certain other related documents that might be available 
electronically, from the EPA Internet Home Page at http://www.epa.gov/. 
To access this document, on the Home Page select ``Laws and 
Regulations'' and then look up the entry for this document under the 
``Federal Register--Environmental Documents.'' You can also go directly 
to the Federal Register listings at http://www.epa.gov/fedrgstr/.
    2. In person. The Agency has established an official record for 
this action under docket control number PF-916. The official record 
consists of the documents specifically referenced in this action, any 
public comments received during an applicable comment period, and other 
information related to this action, including any information claimed 
as confidential business information (CBI). This official record 
includes the documents that are physically located in the docket, as 
well as the documents that are referenced in those documents. The 
public version of the official record does not include any information 
claimed as CBI. The public version of the official record, which 
includes printed, paper versions of any electronic comments submitted 
during an applicable comment period, is available for inspection in the 
Public Information and Records Integrity Branch (PIRIB), Rm. 119, 
Crystal Mall #2, 1921 Jefferson Davis Highway, Arlington, VA, from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.

C. How and to Whom Do I Submit Comments?

    You may submit comments through the mail, in person, or 
electronically. To ensure proper receipt by EPA, it is imperative that 
you identify docket control number PF-916 in the subject line on the 
first page of your response.
    1. By mail. Submit your comments to: Public Information and Records 
Integrity Branch (PIRIB), Information Resources and Services Division 
(7502C), Office of Pesticide Programs (OPP), Environmental Protection 
Agency, Ariel Rios Bldg., 1200 Pennsylvania Ave., NW., Washington, DC 
20460.
    2. In person or by courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Information Resources 
and Services Division (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, Rm. 119, Crystal Mall #2, 1921 
Jefferson Davis Highway, Arlington, VA. The PIRIB is open from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.
    3. Electronically. You may submit your comments electronically by 
e-mail to: ``[email protected],'' or you can submit a computer disk as 
described above. Do not submit any information electronically that you 
consider to be CBI. Avoid the use of special characters and any form of 
encryption. Electronic submissions will be accepted in

[[Page 11053]]

Wordperfect 6.1/8.0 or ASCII file format. All comments in electronic 
form must be identified by docket control number PF-916. Electronic 
comments may also be filed online at many Federal Depository Libraries.

D. How Should I Handle CBI That I Want to Submit to the Agency?

    Do not submit any information electronically that you consider to 
be CBI. You may claim information that you submit to EPA in response to 
this document as CBI 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. In addition to one complete 
version of the comment that includes any information claimed as CBI, a 
copy of the comment that does not contain the information claimed as 
CBI must be submitted for inclusion in the public version of the 
official record. Information not marked confidential will be included 
in the public version of the official record without prior notice. If 
you have any questions about CBI or the procedures for claiming CBI, 
please consult the person identified under ``FOR FURTHER INFORMATION 
CONTACT.''

E. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide copies of any technical information and/or data you used 
that support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at the estimate that you provide.
    5. Provide specific examples to illustrate your concerns.
    6. Make sure to submit your comments by the deadline in this 
notice.
    7. To ensure proper receipt by EPA, be sure to identify the docket 
control number assigned to this action in the subject line on the first 
page of your response. You may also provide the name, date, and Federal 
Register citation.

II. What Action is the Agency Taking?

    EPA has received a pesticide petition as follows proposing the 
establishment and/or amendment of regulations for residues of a certain 
pesticide chemical in or on various food commodities under section 408 
of the Federal Food, Drug, and Comestic Act (FFDCA), 21 U.S.C. 346a. 
EPA has determined that this petition contains data or information 
regarding the elements set forth in section 408(d)(2); however, EPA has 
not fully evaluated the sufficiency of the submitted data at this time 
or whether the data supports granting of the petition. Additional data 
may be needed before EPA rules on the petition.

List of Subjects

    Environmental protection, Agricultural commodities, Feed additives, 
Food additives, Pesticides and pests, Reporting and recordkeeping 
requirements.

    Dated: February 17, 2000.
James Jones,
Director, Registration Division, Office of Pesticide Programs.

Summaries of Petitions

    The petitioner summaries of the pesticide petitions are printed 
below as required by section 408(d)(3) of the FFDCA. The summaries of 
the petitions were prepared by the petitioner and represents the view 
of the petitioner. EPA is publishing the petition summaries verbatim 
without editing them in any way. The petition summaries announce the 
availability of a description of the analytical methods available to 
EPA for the detection and measurement of the pesticide chemical 
residues or an explanation of why no such method is needed.

1. Bayer Corporation

    EPA has received a pesticide petition (PP5F4475) from Bayer 
Corporation, 8400 Hawthorn Road, P.O. Box 4913, Kansas City, MO 64120-
0013 proposing, pursuant to section 408(d) of the Federal Food, Drug, 
and Cosmetic Act (FFDCA), 21 U.S.C. 346a(d), to amend 40 CFR part 180 
by establishing a tolerance for residues of cyfluthrin, cyano (4-
fluoro-3-phenoxyphenyl)methyl-3-(2,2-dichloroethenyl)-2,2- in or on the 
raw agricultural commodity (RAC) cereal grains group; corn, starch; 
corn, refined oil (wet milling); corn, flour; corn, refined oil (dry 
milling); wheat, bran; corn, milled by-products; rice, hulls; wheat, 
milled by-products at 2.0, 3.0, 12, 4.0, 15, 3.0, 4.0, 9.0, 3.0 parts 
per million (ppm). EPA has determined that the petition contains data 
or information regarding the elements set forth in section 408(d)(2) of 
the FFDCA; however, EPA has not fully evaluated the sufficiency of the 
submitted data at this time or whether the data supports granting of 
the petition. Additional data may be needed before EPA rules on the 
petition.

A. Residue Chemistry

    1. Plant metabolism. The metabolism of cyfluthrin in plants is 
adequately understood. Studies have been conducted to delineate the 
metabolism of radiolabeled cyfluthrin in various crops all showing 
similar results. The residue of concern is cyfluthrin.
    2. Analytical method. Adequate analytical methodology (gas/liquid 
chromatography with an electron capture detector (GLC/EC) is available 
for enforcement purposes.
    3. Magnitude of residues. Cyfluthrin is the active ingredient 
(a.i.) in the registered end-use product Tempo 2E Grain, Bin and 
Warehouse Insecticide , EPA FR 3125-ULO. Data to support the proposed 
tolerances have been submitted to the Agency.

B. Toxicological Profile

    1. Acute toxicity. There is a battery of acute toxicity studies for 
cyfluthrin supporting an overall toxicity Category II for the active 
ingredient.
    2. Genotoxicty. 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 (UDS) assay in rat 
hepatocytes. All tests were negative for genotoxicity.
    3. Reproductive and developmental toxicity. An oral developmental 
toxicity study in rats with a maternal and fetal no observed adverse 
effect level (NOAEL) of 10 milligrams/kilograms body weight/day (mg/kg 
bwt/day) highest dose tested (HDT). An oral developmental toxicity 
study in rabbits with a maternal NOAEL of 20 mg/kg bwt/day and a 
maternal lowest effect level (LEL) of 60 mg/kg bwt/day, based on 
decreased bwt gain and decreased food consumption during the dosing 
period. A fetal NOAEL of 20 mg/kg bwt/day and a fetal LEL of 60 mg/kg 
bwt/day were also observed in this study. The LEL was based on 
increased resorptions and increased postimplantation loss. A 3-
generation reproduction study in rats with systemic toxicity NOAELs of 
7.5 and 2.5 mg/kg bwt/day for parental animals and their offspring, 
respectively. At highest dose levels (HDLs), the bwts of parental 
animals and their offspring were reduced.
    4. Subchronic toxicity. A subchronic toxicity feeding study using 
rats demonstrated a NOAEL of 22.5 mg/kg bwt/day, the HDT. A 6-month 
toxicity feeding study in dogs established a NOAEL of 5 mg/kg bwt/day. 
The LEL

[[Page 11054]]

was 15 mg/kg bwt/day based on clinical signs and reduced thymus 
weights.
    5. Chronic toxicity. A 12-month chronic feeding study in dogs 
established a NOAEL of 4 mg/kg bwt/day. The LEL for this study is 
established at 16 mg/kg bwt/day, based on slight ataxia, increased 
vomiting, diarrhea, and decreased body weight. A 24-month chronic 
feeding/carcinogenicity study in rats demonstrated a NOAEL of 2.5 mg/kg 
bwt/day and LEL of 6.2 mg/kg bwt/day, based on decreased body weights 
in males, decreased food consumption in males, and inflammatory foci in 
the kidneys in females. A 24-month carcinogenicity study in mice was 
conducted. Under the conditions of the study there were no carcinogenic 
effects observed. A 24-month chronic feeding/carcinogenicity study in 
rats was conducted. There were no carcinogenic effects observed under 
the conditions of the study.
    6. Animal metabolism. 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.
    7. Metabolite toxicology. No toxicology data have been required for 
cyfluthrin metabolites. The residue of concern is cyfluthrin.
    8. Endocrine disruption. There is no evidence of endocrine effects 
in any of the studies conducted with cyfluthrin, thus, there is no 
indication at this time that cyfluthrin causes endocrine effects.

C. Aggregate Exposure

    1. Dietary exposure--i. Food. Dietary exposure was estimated using 
Novigen's Dietary Exposure Evaluation Model (DEEM ) software; results 
from field trial and processing studies; consumption data from the 
Department of Agricultural (USDA) Continuing Surveys of Food Intake by 
Individuals (CSFIIs), conducted from 1994 through 1996; and information 
on the percentages of crops treated with cyfluthrin. Cyfluthrin is 
currently registered for use in alfalfa, carrots, citrus, cotton, sweet 
corn, sorghum, sunflower, sugarcane, potatoes, peppers, radishes, and 
tomatoes. In addition, it has an import tolerance for hops. Various 
formulations are registered for use in food handling establishments and 
in combination with another active ingredient, for use in field corn, 
pop corn, and sweet corn. Chronic dietary exposure estimates with the 
current label uses plus the proposed uses on stored grain, field and 
pop corn, soybeans, hops, peas and lentils, lettuce, head and stem 
brassica, and mustard greens for the overall U.S. population were 5% of 
the population adjusted dose (PAD) (0.008 mg/kg bwt/day). For the most 
highly exposed population subgroup, children 1 to 6 years of age, the 
exposure was estimated to be 15% of the PAD. Acute dietary exposure 
estimates with the current label uses plus the proposed uses on stored 
grain, field and pop corn, soybeans, hops, peas and lentils, lettuce, 
head and stem brassica, and mustard greens for the overall U.S. 
population were 11% of the aPAD (0.07 mg/kg bwt/day). For the most 
highly exposed population subgroup, children 1 to 6 years of age, the 
exposure was estimated to be 18% of the aPAD.
    ii. Drinking water. Cyfluthrin is immobile in soil, therefore, will 
not leach into ground water. Additionally, due the insolubility and 
lipophilic nature of cyfluthrin, any residues in surface water will 
rapidly and tightly bind to soil particles and remain with sediment, 
therefore, not contributing to potential dietary exposure from drinking 
water. A screening evaluation of leaching potential of a typical 
pyrethroid was conducted using EPA's Pesticide Root Zone Model (PRZM3). 
Based on this screening assessment, the potential concentrations of a 
pyrethroid in ground water at 2 meters are essentially zero (0.001 
parts per billion (ppb)). Surface water concentrations for pyrethroids 
were estimated using PRZM3 and Exposure Analysis Modeling System 
(EXAMS) using standard EPA cotton runoff and Mississippi pond 
scenarios. The maximum concentration predicted in the simulated pond 
was 52 parts per trillion (ppt). Concentration in actual drinking water 
would be much lower. Based on these analyses, the contribution of water 
to the dietary risk estimate is negligible.
    2. Non-dietary exposure. Non-occupational exposure to cyfluthrin 
may occur as a result of inhalation or contact from indoor residential, 
indoor commercial, and outdoor residential uses. Pursuant to the 
requirements of Federal Insecticide, Fungicide, and Rodenticide Act 
(FIFRA) as amended by the Food Quality Protection Act (FQPA) of 1996 
non-dietary and aggregate risk analyses for cyfluthrin were conducted. 
The analyses include evaluation of potential non-dietary acute 
application and post-application exposures. Non-occupational, non-
dietary exposure was assessed based on the assumption that a flea 
infestation control scenario represents a ``worst case'' scenario. For 
the flea control infestation scenario indoor fogger, and professional 
residential turf same day treatments were included for cyfluthrin. 
Deterministic (point values) were used to present a worse case upper-
bound estimate of non-dietary exposure. The non-dietary exposure 
estimates were expressed as systemic absorbed doses for a summation of 
inhalation, dermal, and incidental ingestion exposures. These worst 
case non-dietary exposures were aggregated with chronic dietary 
exposures to evaluate potential health risks that might be associated 
with cyfluthrin products. The chronic dietary exposures were expressed 
as an oral absorbed dose to combine with the non-dietary systemic 
absorbed doses for comparison to a systemic absorbed dose NOAEL. 
Results for each potential exposed subpopulation (of adults, children 
1-6 years, and infants 1 year) were compared to the systemic absorbed 
dose NOAEL for cyfluthrin to provide estimates of margins of exposure 
(MOE). The large MOEs for cyfluthrin clearly demonstrate a substantial 
degree of safety. The total non-dietary MOEs are 3,800, 2,700, and 
2,500 for adults, children (1-6 years), and infants (1 year), 
respectively. The aggregate MOE for adults is approximately 3,700 and 
the MOEs for infants and children exceed 2,400. The non-dietary methods 
used in the analyses can be characterized as highly conservative. This 
is due to the conservatism inherent in the calculation procedures and 
input assumptions. An example of this is the conservatism inherent in 
the jazzercise methodology's over-representation of residential post-
application exposures. It is important to acknowledge that these MOEs 
are likely to significantly underestimate actual MOEs due to a variety 
of conservative assumptions and biases inherent in the derivatization 
of exposure by this method. Therefore, it can be concluded that large 
MOEs associated with potential non-dietary and aggregate exposures to 
cyfluthrin will result in little or no health risks to exposed persons. 
The aggregate risk analysis demonstrates compliance with the health-
based requirements of the FQPA of 1996 for the current label uses. The 
additional use of cyfluthrin on field corn and soybean crops will have 
no impact on the analysis for non-dietary exposure.

D. Cumulative Effects

    Bayer will submit information for EPA to consider concerning 
potential cumulative effects of cyfluthrin consistent with the schedule 
established by EPA at 62 FR 42020 (August 4, 1997) (FRL-5734-6) and 
other EPA publications pursuant to the FQPA.

[[Page 11055]]

E. Safety Determination

    1. U.S. population. Based on the exposure assessments described 
above and on the completeness and reliability of the toxicity data, it 
can be concluded that total aggregate exposure to cyfluthrin from all 
label uses will utilize less than 20% of the RfD for chronic dietary 
exposures and that MOE in excess of 1,000 exist for aggregate exposure 
to cyfluthrin for non-cupational exposure. EPA generally has no 
concerns for exposures below 100% of the RfD, because the RfD 
represents the level at or below which daily aggregate exposure over a 
lifetime will not pose appreciable risks to human health. MOE of 100 or 
more (300 for infants and children) also indicate an adequate degree of 
safety. Thus, it can be concluded that there is a reasonable certainty 
that no harm will result from aggregate exposure to cyfluthrin 
residues.
    2. Infants and children. In assessing the potential for additional 
sensitivity of infants and children to residues of cyfluthrin, the data 
from developmental studies in both rat and rabbit and a 2-generation 
reproduction study in the rat can be considered. The developmental 
toxicity studies evaluate any potential adverse effects on the 
developing animal resulting from pesticide exposure of the mother 
during prenatal development. The reproduction study evaluates any 
effects from exposure to the pesticide on the reproductive capability 
of mating animals through 2-generations, as well as any observed 
systemic toxicity. The toxicology data which support these uses of 
cyfluthrin include: A rat oral developmental toxicity study in which 
maternal and fetal NOAELs of 10 mg/kg bwt/day HGT were observed. An 
oral developmental toxicity study in which rabbits had a maternal NOAEL 
of 20 mg/kg bwt/day and a maternal LEL of 60 mg/kg bwt/day, based on 
decreased bodyweight gain and decreased food consumption during the 
dosing period. A fetal NOAEL of 20 mg/kg bwt/day and a fetal LEL of 60 
mg/kg bwt/day were also observed in this study. The LEL was based on 
increased resorptions and increased postimplantation loss. An oral 
developmental toxicity study performed with beta-cyfluthrin, the 
resolved isomer mixture of cyfluthrin, has been submitted to the Agency 
and is currently under review. A developmental toxicity study in rats 
exposed via inhalation to liquid aerosols of cyfluthrin revealed 
developmental toxicity, but only in the presence of maternal toxicity. 
The developmental NOAEL was 0.46 mg/m3 on the basis of 
reduced placental and fetal weights, and delayed ossification. The 
NOAEL for overt maternal toxicity was 0.46 mg/m3, the LDT. 
In a rat 3-generation reproduction study, systemic toxicity NOAELs of 
7.5 and 2.5 mg/kg bwt/day for parental animals and their offspring, 
respectively, were observed. At HDL, the bwts of parental animals and 
their offspring were reduced. Another multiple-generation reproduction 
study in rats has been submitted to the Agency and is currently under 
review. To assess acute dietary exposure and determine a MOE for the 
overall U.S. population and certain subgroups, the Agency has used the 
rabbit developmental toxicity study which had a maternal NOAEL of 20 
mg/kg bwt/day. Because the toxicological endpoint is one of 
developmental toxicity, the population group of concern for this 
analysis was women aged 13 and above. This subgroup most closely 
approximates women of child-bearing age. The MOE is calculated as the 
ratio of the NOAEL to the exposure. The Agency calculated the MOE to be 
over 600. Generally, MOE's greater than 100 for data derived from 
animal studies are regarded as showing no appreciable risk. FFDCA 
section 408 provides that EPA may apply an additional safety factor for 
infants and children. The additional safety factor may be used when 
prenatal and postnatal threshold effects were observed in studies or to 
account for incompleteness of the toxicity data base. The results of 
the 3-generation study in rats provided evidence suggesting that, with 
respect to effects of cyfluthrin on body weight, pups were more 
sensitive than adult rats. Thus, the Agency determined that an 
additional 3-fold uncertainty factor (UF) should be used in risk 
assessments to ensure adequate protection of infants and children. 
Generally, EPA considers MOEs of at least 100 to indicate an adequate 
degree of safety. With an additional 3x uncertainty factor, this would 
be 300 for infants and children.

F. International Tolerances

    There is a Codex maximum residue level (MRLs) for maize of 0.05 
ppm. There is a Codex MRL for sweet corn of 0.02 ppm.
    2. Bayer Corporation. EPA has received a pesticide petition 
(PP0F6084) from Bayer Corporation, 8400 Hawthorn Road, P.O. Box 4913, 
Kansas City, MO 64120-0013 proposing, pursuant to section 408(d) of the 
FFDCA, 21 U.S.C. 346a(d), to amend 40 CFR part 180 by establishing a 
tolerance for residues of cyfluthrin, cyano (4-fluoro-3-
phenoxyphenyl)methyl-3-(2,2-dichloroethenyl)-2,2- in or on the RAC, 
mustard greens, greens; lettuce, head; lettuce, leaf; head and stem 
brassica subgroup (5A) at 7.0, 2.0, 3.0, 2.0 ppm. EPA has determined 
that the petition contains data or information regarding the elements 
set forth in section 408(d)(2) of the FFDCA; however, EPA has not fully 
evaluated the sufficiency of the submitted data at this time or whether 
the data supports granting of the petition. Additional data may be 
needed before EPA rules on the petition.

A. Residue Chemistry

    1. Plant metabolism. The metabolism of cyfluthrin in plants is 
adequately understood. Studies have been conducted to delineate the 
metabolism of radiolabeled cyfluthrin in various crops all showing 
similar results. The residue of concern is cyfluthrin.
    2. Analytical method. Adequate analytical methodology GLC/EC 
detector is available for enforcement purposes.
    3. Magnitude of residues. Cyfluthrin is the active ingredient in 
the registered end-use product Baythroid 2 Emulsifiable Pyrethroid 
Insecticide, EPA FR 3125-351. Data to support the proposed tolerances 
have been submitted to the Agency.

B. Toxicological Profile

    1. Acute toxicity. There is a battery of acute toxicity studies for 
cyfluthrin supporting an overall toxicity Category II for the active 
ingredient.
    2. Genotoxicity. Mutagenicity tests were conducted, including 
several gene mutation assays (reverse mutation and recombination assays 
in bacteria and a CHO/HGPRT assay; a structural chromosome aberration 
assay (CHO/sister chromatid exchange assay); and an UDS assay in rat 
hepatocytes. All tests were negative for genotoxicity.
    3. Reproductive and developmental toxicity. An oral developmental 
toxicity study in rats with a maternal and fetal NOAEL of 10 mg/kg bwt/
day HDT. An oral developmental toxicity study in rabbits with a 
maternal NOAEL of 20 mg/kg bwt/day and a maternal LEL of 60 mg/kg bwt/
day, based on decreased body weight gain and decreased food consumption 
during the dosing period. A fetal NOAEL of 20 mg/kg bwt/day and a fetal 
LEL of 60 mg/kg bwt/day were also observed in this study. The LEL was 
based on increased resorptions and increased post-implantation loss. A 
3-generation reproduction study in rats with systemic toxicity NOAELs 
of 7.5 and 2.5 mg/kg bwt/day for parental animals and their offspring, 
respectively. At HDLs, the body weights of parental animals and their 
offspring were reduced.

[[Page 11056]]

    4. Subchronic toxicity. A subchronic toxicity feeding study using 
rats demonstrated a NOAEL of 22.5 mg/kg bwt/day, the HDT. A 6-month 
toxicity feeding study in dogs established a NOAEL of 5 mg/kg bwt/day. 
The LEL was 15 mg/kg bwt/day based on clinical signs and reduced thymus 
weights.
    5. Chronic toxicity. A 12-month chronic feeding study in dogs 
established a NOAEL of 4 mg/kg bwt/day. The LEL for this study is 
established at 16 mg/kg bwt/day, based on slight ataxia, increased 
vomiting, diarrhea and decreased body weight. A 24-month chronic 
feeding/carcinogenicity study in rats demonstrated a NOAEL of 2.5 mg/kg 
bwt/day and LEL of 6.2 mg/kg bwt/day, based on decreased body weights 
in males, decreased food consumption in males, and inflammatory foci in 
the kidneys in females. A 24-month carcinogenicity study in mice was 
conducted. Under the conditions of the study there were no carcinogenic 
effects observed. A 24-month chronic feeding/carcinogenicity study in 
rats was conducted. There were no carcinogenic effects observed under 
the conditions of the study.
    6. Animal metabolism. 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.
    7. Metabolite toxicology. No toxicology data have been required for 
cyfluthrin metabolites. The residue of concern is cyfluthrin.
    8. Endocrine disruption. There is no evidence of endocrine effects 
in any of the studies conducted with cyfluthrin, thus, there is no 
indication at this time that cyfluthrin causes endocrine effects.

C. Aggregate Exposure

    1. Dietary exposure--i. Food. Dietary exposure was estimated using 
Novigen's Dietary Exposure Evaluation Model (DEEM ) software; results 
from field trial and processing studies; consumption data from the USDA 
Continuing Surveys of Food Intake by Individuals (CSFIIs), conducted 
from 1994 through 1996; and information on the percentages of crops 
treated with cyfluthrin. Cyfluthrin is currently registered for use in 
alfalfa, carrots, citrus, cotton, sweet corn, sorghum, sunflower, 
sugarcane, potatoes, peppers, radishes, and tomatoes. In addition, it 
has an import tolerance for hops. Various formulations are registered 
for use in food handling establishments and in combination with another 
active ingredient, for use in field corn, pop corn, and sweet corn. 
Chronic dietary exposure estimates with the current label uses plus the 
proposed uses on stored grain, field and pop corn, soybeans, hops, peas 
and lentils, lettuce, head and stem brassica, and mustard greens for 
the overall U.S. population were 5% of the PAD (0.008 mg/kg bwt/day). 
For the most highly exposed population subgroup, children 1 to 6 years 
of age, the exposure was estimated to be 15% of the PAD. Acute dietary 
exposure estimates with the current label uses plus the proposed uses 
on stored grain, field and pop corn, soybeans, hops, peas and lentils, 
lettuce, head and stem brassica, and mustard greens for the overall 
U.S. population were 11% of the aPAD (0.07 mg/kg bwt/day). For the most 
highly exposed population subgroup, children 1 to 6 years of age, the 
exposure was estimated to be 18% of the aPAD.
    ii. Drinking water. Cyfluthrin is immobile in soil, therefore, will 
not leach into ground water. Additionally, due the insolubility and 
lipophilic nature of cyfluthrin, any residues in surface water will 
rapidly and tightly bind to soil particles and remain with sediment, 
therefore, not contributing to potential dietary exposure from drinking 
water. A screening evaluation of leaching potential of a typical 
pyrethroid was conducted using EPA's Pesticide Root Zone Model (PRZM3). 
Based on this screening assessment, the potential concentrations of a 
pyrethroid in ground water at 2 meters are essentially zero (0.001 
ppb). Surface water concentrations for pyrethroids were estimated using 
PRZM3 and Exposure Analysis Modeling System (EXAMS) using Standard EPA 
cotton runoff and Mississippi pond scenarios. The maximum concentration 
predicted in the simulated pond was 52 ppt. Concentration in actual 
drinking water would be much lower. Based on these analyses, the 
contribution of water to the dietary risk estimate is negligible.
    2. Non-dietary exposure. Non-occupational exposure to cyfluthrin 
may occur as a result of inhalation or contact from indoor residential, 
indoor commercial, and outdoor residential uses. Pursuant to the 
requirements of FIFRA as amended by the FQPA of 1996 non-dietary and 
aggregate risk analyses for cyfluthrin were conducted. The analyses 
include evaluation of potential non-dietary acute application and post-
application exposures. Non-occupational, non-dietary exposure was 
assessed based on the assumption that a flea infestation control 
scenario represents a ``worst case'' scenario. For the flea control 
infestation scenario indoor fogger, and professional residential turf 
same day treatments were included for cyfluthrin. Deterministic (point 
values) were used to present a worse case upper-bound estimate of non-
dietary exposure. The non-dietary exposure estimates were expressed as 
systemic absorbed doses for a summation of inhalation, dermal, and 
incidental ingestion exposures. These worst case non-dietary exposures 
were aggregated with chronic dietary exposures to evaluate potential 
health risks that might be associated with cyfluthrin products. The 
chronic dietary exposures were expressed as an oral absorbed dose to 
combine with the non-dietary systemic absorbed doses for comparison to 
a systemic absorbed dose NOAEL. Results for each potential exposed 
subpopulation (of adults, children 1-6 years, and infants 1 year) were 
compared to the systemic absorbed dose NOAEL for cyfluthrin to provide 
estimates of MOE. The large MOEs for cyfluthrin clearly demonstrate a 
substantial degree of safety. The total non-dietary MOEs are 3,800, 
2,700, and 2,500 for adults, children (1-6 years), and infants ( 1 
year), respectively. The aggregate MOE for adults is approximately 
3,700 and the MOEs for infants and children exceed 2,400. The non-
dietary methods used in the analyses can be characterized as highly 
conservative. This is due to the conservatism inherent in the 
calculation procedures and input assumptions. An example of this is the 
conservatism inherent in the jazzercise methodology's over-
representation of residential post-application exposures. It is 
important to acknowledge that these MOEs are likely to significantly 
underestimate actual MOEs due to a variety of conservative assumptions 
and biases inherent in the derivatization of exposure by this method. 
Therefore, it can be concluded that large MOEs associated with 
potential non-dietary and aggregate exposures to cyfluthrin will result 
in little or no health risks to exposed persons. The aggregate risk 
analysis demonstrates compliance with the health-based requirements of 
the FQPA of 1996 for the current label uses. The additional use of 
cyfluthrin on field corn and soybean crops will have no impact on the 
analysis for non-dietary exposure.

D. Cumulative Effects

    Bayer will submit information for EPA to consider concerning 
potential cumulative effects of cyfluthrin consistent with the schedule 
established by EPA at 62 FR 42020 (August 4, 1997) (FRL-5734-6) and 
other EPA publications pursuant to the FQPA.

[[Page 11057]]

E. Safety Determination

    1. U.S. population. Based on the exposure assessments described 
above and on the completeness and reliability of the toxicity data, it 
can be concluded that total aggregate exposure to cyfluthrin from all 
label uses will utilize less than 20% of the RfD for chronic dietary 
exposures and that MOEs in excess of 1,000 exist for aggregate exposure 
to cyfluthrin for non-occupational exposure. EPA generally has no 
concerns for exposures below 100% of the RfD, because the RfD 
represents the level at or below which daily aggregate exposure over a 
lifetime will not pose appreciable risks to human health. MOE of 100 or 
more (300 for infants and children) also indicate an adequate degree of 
safety. Thus, it can be concluded that there is a reasonable certainty 
that no harm will result from aggregate exposure to cyfluthrin 
residues.
    2. Infants and children. In assessing the potential for additional 
sensitivity of infants and children to residues of cyfluthrin, the data 
from developmental studies in both rat and rabbit and a 2-generation 
reproduction study in the rat can be considered. The developmental 
toxicity studies evaluate any potential adverse effects on the 
developing animal resulting from pesticide exposure of the mother 
during prenatal development. The reproduction study evaluates any 
effects from exposure to the pesticide on the reproductive capability 
of mating animals through 2-generations, as well as any observed 
systemic toxicity. The toxicology data which support these uses of 
cyfluthrin include: A rat oral developmental toxicity study in which 
maternal and fetal NOAELs of 10 mg/kg bwt/day HDT were observed. An 
oral developmental toxicity study in which rabbits had a maternal NOAEL 
of 20 mg/kg bwt/day and a maternal LEL of 60 mg/kg bwt/day, based on 
decreased bwt gain and decreased food consumption during the dosing 
period. A fetal NOAEL of 20 mg/kg bwt/day and a fetal LEL of 60 mg/kg 
bwt/day were also observed in this study. The LEL was based on 
increased resorptions and increased postimplantation loss. An oral 
developmental toxicity study performed with beta-cyfluthrin, the 
resolved isomer mixture of cyfluthrin, has been submitted to the Agency 
and is currently under review. A developmental toxicity study in rats 
exposed via inhalation to liquid aerosols of cyfluthrin revealed 
developmental toxicity, but only in the presence of maternal toxicity. 
The developmental NOAEL was 0.46 mg/m3 on the basis of 
reduced placental and fetal weights, and delayed ossification. The 
NOAEL for overt maternal toxicity was  0.46 mg/m3, the LDT. 
In a rat 3-generation reproduction study, systemic toxicity NOAELs of 
7.5 and 2.5 mg/kg bwt/day for parental animals and their offspring, 
respectively, were observed. At HDL, the body weights of parental 
animals and their offspring were reduced. Another multiple-generation 
reproduction study in rats has been submitted to the Agency and is 
currently under review. To assess acute dietary exposure and determine 
a MOE for the overall U.S. population and certain subgroups, the Agency 
has used the rabbit developmental toxicity study which had a maternal 
NOAEL of 20 mg/kg bwt/day. Because the toxicological endpoint is one of 
developmental toxicity, the population group of concern for this 
analysis was women aged 13 and above. This subgroup most closely 
approximates women of child-bearing age. The MOE is calculated as the 
ratio of the NOAEL to the exposure. The Agency calculated the MOE to be 
over 600. Generally, MOEs greater than 100 for data derived from animal 
studies are regarded as showing no appreciable risk. FFDCA section 408 
provides that EPA may apply an additional safety factor for infants and 
children. The additional safety factor may be used when prenatal and 
postnatal threshold effects were observed in studies or to account for 
incompleteness of the toxicity data base. The results of the 3-
generation study in rats provided evidence suggesting that, with 
respect to effects of cyfluthrin on body weight, pups were more 
sensitive than adult rats. Thus, the Agency determined that an 
additional 3-fold uncertainty factor (UF) should be used in risk 
assessments to ensure adequate protection of infants and children. 
Generally, EPA considers MOEs of at least 100 to indicate an adequate 
degree of safety. With an additional 3x UF, this would be 300 for 
infants and children.

F. International Tolerances

    There are currently no Codex maximum residue levels for mustard 
greens, lettuce or head and stem brassicas.
[FR Doc. 00-4791 Filed 2-29-00; 8:45 am]
BILLING CODE 6560-50-F