FLUORIDE ACTION NETWORK PESTICIDE PROJECT

Return to FAN's Pesticide Homepage

Return to Cyfluthrin Index Page


Cyfluthrin (Bayer). August 14, 1998. Pesticide Tolerance Petition. Federal Register.


 http://www.epa.gov/fedrgstr/EPA-PEST/1998/August/Day-14/p21903.htm

[Federal Register: August 14, 1998 (Volume 63, Number 157)]
[Notices]               
[Page 43705-43710]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr14au98-80]

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

ENVIRONMENTAL PROTECTION AGENCY

[PF-822; FRL-6019-8]

 
Notice of Filing of Pesticide Petitions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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

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 the docket control number PF-822, must 
be received on or before September 14, 1998.
ADDRESSES: By mail submit written comments to: Public Information and 
Records Integrity Branch, Information Resources and Services Division 
(7506C), Office of Pesticides Programs, Environmental Protection 
Agency, 401 M St., SW., Washington, DC 20460. In person bring comments 
to: Rm. 1132, CM #2, 1921 Jefferson Davis Highway, Arlington, VA.
    Comments and data may also be submitted electronically to: opp-
docket@epamail.epa.gov. Follow the instructions under ``SUPPLEMENTARY 
INFORMATION.'' No confidential business information should be submitted 
through e-mail.
    Information submitted as a comment concerning this document may be

[[Page 43706]]

claimed confidential by marking any part or all of that information as 
``Confidential Business Information'' (CBI). CBI should not be 
submitted through e-mail. Information marked as CBI will not be 
disclosed except in accordance with procedures set forth in 40 CFR part 
2. A copy of the comment 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. All written 
comments will be available for public inspection in Rm. 1132 at the 
address given above, from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays.

FOR FURTHER INFORMATION CONTACT: The product manager listed in the 
table below:

------------------------------------------------------------------------
                                   Office location/                     
        Product Manager            telephone number          Address    
------------------------------------------------------------------------
Mark Dow......................  Rm. 214, CM #2, 703-    1921 Jefferson  
                                 305-5533, e-            Davis Highway, 
                                 mail:dow.mark@epamail   Arlington, VA  
                                 .epa.gov.                              
Bipin Gandhi (PM 22)..........  Rm. 707A, CM #2, 703-   1921 Jefferson  
                                 308-8380, e-            Davis Highway, 
                                 mail:gandhi.bipin@epa   Arlington, VA  
                                 mail.epa.gov.                          
------------------------------------------------------------------------

SUPPLEMENTARY INFORMATION: EPA has received pesticide petitions as 
follows proposing the establishment and/or amendment of regulations for 
residues of certain pesticide chemicals 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 these petitions 
contain 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.
    The official record for this notice of filing, as well as the 
public version, has been established for this notice of filing under 
docket control number [PF-822] (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 record is located at the address in 
``ADDRESSES'' at the beginning of this document.
    Electronic comments can be sent directly to EPA at:
    opp-docket@epamail.epa.gov


    Electronic comments must be submitted as an ASCII file avoiding the 
use of special characters and any form of encryption. Comments and data 
will also be accepted on disks in Wordperfect 5.1 file format or ASCII 
file format. All comments and data in electronic form must be 
identified by the docket number (insert docket number) and appropriate 
petition number. Electronic comments on notice may be filed online at 
many Federal Depository Libraries.

List of Subjects

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

    Dated:August 5,1998.

Arnold E. Layne,

Acting Director, Registration Division, Office of Pesticide Programs.

Summaries of Petitions

    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 petitioners and represent the views of 
the petitioners. EPA is publishing the petition summaries verbatim 
without editing them in any way. The petition summary announces 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

PP 4F4330

     EPA has received a pesticide petition (PP 4F4330) from Bayer 
Corporation, 8400 Hawthorn Road, PO Box 4913, Kansas City MO, 64120-
2000 proposing pursuant to section 408(d) of the Federal Food, Drug, 
and Cosmetic Act, 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-
dimethylcyclopropanecarboxylate) in or on the raw agricultural 
commodity potato at 0.01 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) 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 Reg. No. 3125-351. Data to support the proposed 
tolerances have been submitted to the Agency.

B. Toxicological Profile

    The database for cyfluthrin is current and complete. Toxicology 
data cited in support of these tolerances include:
    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 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 NOEL of 10 milligram/ 
kilograms/body weight/day (mg/kg/bw/day) (highest dose tested (HDT)).
    An oral developmental toxicity study in rabbits with a maternal 
NOEL of 20 mg/kg bw/day and a maternal lowest effect level (LEL) of 60 
mg/kg bw/day, based on decreased body weight gain

[[Page 43707]]

and decreased food consumption during the dosing period. A fetal NOEL 
of 20 mg/kg bw/day and a fetal LEL of 60 mg/kg bw/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 
NOELs of 7.5 and 2.5 mg/kgbw/day for parental animals and their 
offspring, respectively. At HDTs, the body weights of parental animals 
and their offspring were reduced.
    4. Subchronic toxicity. A subchronic toxicity feeding study using 
rats demonstrated a NOEL of 22.5 mg/kg bw/day, the HDT.
    A 6-month toxicity feeding study in dogs established a NOEL of 5 
mg/kg bw/day. The LEL was 15 mg/kg bw/day based on clinical signs and 
reduced thymus weights.
    5. Chronic toxicity. A 12-month chronic feeding study in dogs 
established a NOEL of 4 mg/kg bw/day. The LEL for this study is 
established at 16 mg/kg bw/day, based on slight ataxia, increased 
vomiting, diarrhea and decreased body weight.
    A 24-month chronic feeding/carcinogenicity study in rats 
demonstrated a NOEL of 2.5 mg/kg bw/day and LEL of 6.2 mg/kg bw/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. No evidence of endocrine effects was 
observed 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--Food. Dietary exposure was estimated using 
Novigen's Dietary Exposure Evaluation Model (DEEMa) software; results 
from field trial and processing studies; consumption data from the USDA 
Continuing Surveys of Food Intake by Individuals (CSFIIs), conducted 
from 1989 through 1992; and information on the percentages of the crop 
treated with cyfluthrin.
    Cyfluthrin is currently registered for use in alfalfa, citrus, 
sweet corn, cotton, sorghum, sunflower, sugarcane, carrots, 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.
    Considering all current registered uses with the addition of 
potatoes, chronic dietary exposure estimates for the overall U.S. 
population were 0.8% of the RfD (0.008 mg/kg bw/day). For the most 
highly exposed population subgroup, children 1 to 6 years of age non-
nursing infants (<1 year), the exposure was estimated to be 0.000153 
mg/kg bw/day, or 1.9% of the RfD.
    Acute dietary exposures were estimated for the overall U.S. 
population, females 13-years and older, children, ages 1-6 and 7-12 
years, infants, non-nursing and nursing. The exposure was compared to 
the NOEL of 20 mg/kg bw/day to estimate the Margins of Exposures 
(MOEs).
    For the overall U.S. population the 95th, 99th and 99.9th 
percentile of exposure the MOEs were calaculated as 11,751; 6,882; and 
4,439 respectively.
    For women aged 13-years and older the 95th, 99th and 99.9th 
percentile of exposure the MOEs were calculcated as 19,719; 13,147 and 
7,165 respectively.
    Lastly, for the potentially highest exposed population subgroup, 
non-nursing infants, the 95th, 99th and 99.9th percentile of exposure 
to the MOEs were calculated at 6,201; 4,595; and 2,933, respectively.
    2. Drinking water. Cyfluthrin is immobile in soil, therefore, will 
not leach into groundwater. 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.
    3. 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 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 no-
observed-effect-level (NOEL). Results for each potential exposed 
subpopulation (of adults, children 1-6 years, and infants <1 year) were 
compared to the systemic absorbed dose NOEL 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, 2,600, and 
2,400 for adults, children (1-6 years), and infants (<1 year), 
respectively. When chronic dietary exposure is aggregated with non-
dietary exposure, the aggregate MOE for adults is relatively unchanged 
approximately 3,800 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

[[Page 43708]]

example of this is the conservatism inherent in the jazzercise 
methodology 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 and supports the continued 
registration and use of residential, commercial, and agricultural 
products containing cyfluthrin.

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) and other EPA 
publications pursuant to the FQPA.

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 
uses will utilize less than 2% of the RfD for chronic dietary exposures 
and that margins of exposure 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 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 tolerances include: 
toxicity study in rats with a maternal and fetal NOEL of 10 mg/kg bw/
day (HDT).
    An oral developmental toxicity study in rabbits with a maternal 
NOEL of 20 mg/kg bw/day and a maternal LEL of 60 mg/kg bw/day, based on 
decreased body weight gain and decreased food consumption during the 
dosing period. A fetal NOEL of 20 mg/kg bw/day and a fetal LEL of 60 
mg/kg bw/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 NOEL was 0.46 
mg/m3 on the basis of reduced placental and fetal weights, and delayed 
ossification. The NOEL for overt maternal toxicity was <0.46 mg/m3, the 
LDT.
    A 3-generation reproduction study in rats with systemic toxicity 
NOELs of 7.5 and 2.5 mg/kg bw/day for parental animals and their 
offspring, respectively. At HDLs, 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.
    The Agency used the rabbit developmental toxicity study with a 
maternal NOEL of 20 mg/kg bw/day to assess acute dietary exposure and 
determine a MOE for the overall U.S. population and certain subgroups. 
Since this toxicological endpoint pertains to developmental toxicity 
the population group of concern for this analysis was women aged 13 and 
above, the subgroup which most closely approximates women of child-
bearing age. The MOE is calculated as the ratio of the NOEL to the 
exposure. The Agency calculated the MOE to be over 600. The Tier III 
acute dietary analysis calculated an MOE over 7,000 for this age group. 
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 in the case of threshold effects to 
account for pre- and post-natal effects and the completeness of the 
toxicity database.
    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 margins of exposure 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. Using 
the exposure assessments described above and based on the described 
toxicity data aggregate exposure to infants and children indicate a MOE 
in excess of 2,500. Thus, it can be concluded that there is a 
reasonable certainty that no harm will result to infants and children 
from aggregate exposure to cyfluthrin residues.

F. International Tolerances

    There are no Codex maximum residue levels (MRLs) currently 
established for residues of cyfluthrin on potatoes commodities.
    The available data indicate that there is reasonable certainty of 
no harm from the aggregate exposure from all currently registered uses 
of cyfluthrin. Thus consistent with the provisions of the FFDCA as 
amended August 3, 1996, the time limitations on established cyfluthrin 
tolerance should be removed. (Mark Dow).


[FR Doc. 98-21903 Filed 8-13-98; 8:45 am]
BILLING CODE 6560-50-F