Federal Register / Vol. 65, No. 12 / Wednesday, January 19, 2000 / Notices 2949

Branch (PIRIB), Rm. 119, Crystal Mall 2

(CM 2), 1921 Jefferson Davis Hwy.,

Arlington, VA, from 8:30 a.m. to 4 p.m.,

Monday through Friday, excluding legal

holidays. The PIRIB telephone number

is (703) 305–5805.

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 OPP–30489 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, 401 M St., SW., 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, CM 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: ‘‘opp-docket@epa.gov,’’ 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

WordPerfect 6.1/8.0 or ASCII file

format. All comments in electronic form

must be identified by docket control

number OPP–30489. 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. Offer alternative ways to improve

the registration activity.

7. Make sure to submit your

comments by the deadline in this

notice.

8. 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. Registration Application

EPA received application as follows

to register pesticide product containing

active ingredient not included in any

previously registered product pursuant

to the provision of section 3(c)(4) of

FIFRA. Notice of receipt of this

application does not imply a decision

by the Agency on the application.

Product Containing Active Ingredient

not Included in any Previously

Registered Product

File Symbol: 69876–R: Applicant:

Camas Technologies, Inc., PO Box 1357,

Broomfield, Colorado 80038–1357.

Product name: QWEL Fungicide. Active

Ingredient: Macleaya Extract. Proposed

Classification/Use: None. For foliar

control of fungi on greenhouse

ornamentals. Type registration:

Conditional.

List of Subjects

Environmental protection, Pesticides

and pest.

Dated: January 5, 2000

James Jones,

Director, Registration Division, Office of

Pesticide Programs.

[FR Doc. 00–1217 Filed 1–18–00; 8:45 am

BILLING CODE 6560–50–F

ENVIRONMENTAL PROTECTION

AGENCY

[PF–912; FRL–6485–8]

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.

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–912, must be

received on or before February 18, 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–912 in the subject

line on the first page of your response.

FOR FURTHER INFORMATION CONTACT: By

mail: Cynthia Giles-Parker, Registration

Support Branch, Registration Division

(7505C), Office of Pesticide Programs,

Environmental Protection Agency, 401

M St., SW., Washington, DC 20460;

telephone number: (703) 305–7740; email address: gilesparker.cynthia@epa.gov.

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:

Categories NAICS Examples of potentially affected entities

Industry 111 Crop production

112 Animal production

311 Food manufacturing

2950 Federal Register / Vol. 65, No. 12 / Wednesday, January 19, 2000 / Notices

Categories NAICS Examples of potentially affected entities

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–

912. 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

(CM 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–912 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, 401 M St., SW., 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, CM 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: ‘‘opp-docket@epa.gov,’’ 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

Wordperfect 6.1/8.0 or ASCII file

format. All comments in electronic form

must be identified by docket control

number PF–912. 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 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: January 11, 2000

James Jones,

Director, Registration Division, Office of

Pesticide Programs.

Summaries of Petition

The petitioner summary of the

pesticide petition is printed below as

required by section 408(d)(3) of the

FFDCA. The summary of the petition

was prepared by the petitioner and

represents the view of the petitioners.

Federal Register / Vol. 65, No. 12 / Wednesday, January 19, 2000 / Notices 2951

EPA is publishing the petition summary

verbatim without editing it 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. Novartis Crop Protection, Inc.

PP 9F05070

EPA has received a pesticide petition

(PP 9F05070) from Novartis Crop

Protection, Inc., PO Box 18300,

Greensboro, NC 27419, 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 Trifloxystrobin in or on the

raw agricultural commodities almond

nutmeats at 0.02 parts per million

(ppm), almond hulls at 1.5 ppm, fruiting

vegetables crop group at 0.7 ppm, hops

- dried cones at 11 ppm, potato tubers

at 0.02 ppm, sugarbeet roots at 0.05

ppm, sugarbeet tops at 2.5 ppm,

sugarbeet dried pulp at 0.25 ppm, wheat

grain at 0.05 ppm, wheat forage at 0.03

ppm, wheat hay at 0.2 ppm, wheat straw

at 0.05 ppm, and wheat aspirated grain

fractions at 0.5 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 trifloxystrobin in plants (cucumbers,

apples, wheat and peanuts) is well

understood. Identified metabolic

pathways are substantially similar in

plants and animals (goat, rat and hen).

Novartis proposes trifloxystrobin, per

se, as the residue of concern for

tolerance setting purposes.

2. Analytical method. Novartis Crop

Protection Inc. has submitted practical

analytical methodology for detecting

and measuring levels of trifloxystrobin

in or on raw agricultural commodities.

The limit of detection (LOD) for each

analyte of this method is 0.08 ng

injected, and the limit of quantitation

(LOQ) is 0.02 ppm. The method is based

on crop specific cleanup procedures and

determination by gas chromatography

with nitrogen-phosphorus detection.

3. Magnitude of residues — residue

trials. A residue program was performed

for trifloxystrobin on a full geography of

tomatoes and peppers as representative

fruiting vegetable crops, potatoes as a

representative crop of tuberous and

corm vegetables, almonds, hops, wheat,

and sugarbeets. A study was conducted

on indicator crops to assay for

secondary residues in rotational crops.

Novartis also completed a three-level

poultry study to determine the rate of

transfer of residues of trifloxystrobin

from residues in animal feed to poultry

commodities.

i. Acute toxicity. Studies conducted

with the technical material of

trifloxystrobin:

• Rat acute oral toxicity study with a

LD50 >5,000 mg/kg

• Mouse acute oral toxicity study

with a LD50 >5,000 mg/kg

• Rabbit acute dermal toxicity study

with a LD50 >2,000 mg/kg

• Rat acute dermal toxicity study

with a LD50 >2,000 mg/kg

• Rat acute inhalation toxicity study

with a LC50 >4.65 mg/L

• Rabbit eye irritation study showing

slight irritation (Category III)

• Rabbit dermal irritation study

showing slight irritation (Category IV)

• Guinea pig dermal sensitization

study with the Buehler’s method

showing negative findings

• Guinea pig clem sal sensitization

study with the Maximization method

showing some positive findings

ii. Genotoxicty. No genotoxic activity

is expected of trifloxystrobin under invivo or physiological conditions. The

compound has been tested for its

potential to induce gene mutation and

chromosomal changes in five different

test systems. The only positive finding

was seen in the in vitro test system

(Chinese hamster V79 cells) as a slight

increase in mutant frequency at a very

narrow range (250 – 278 μg/ml) of

cytotoxic and precipitating

concentrations (compound solubility in

water was reported to be 0.61 μg/ml;

precipitate was visually noted in culture

medium at 150 μg/ml). The chemical

was found to be non-mutagenic in the

in vivo system or all other in vitro

systems. Consequently, the limited gene

mutation activity in the V79 cell line is

considered a nonspecific effect under

non-physiological in vitro conditions

and not indicative of a real mutagenic

hazard.

iii. Reproductive and developmental

toxicity. 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 toxicity and the

completeness of the database. Based on

the current toxicological data

requirements, the database on

trifloxystrobin relative to pre- and postnatal effects for children is complete.

In assessing the potential for

additional sensitivity of infants and

children to residues of trifloxystrobin,

Novartis considered data from

teratogenicity studies in the rat and the

rabbit and a 2–generation reproduction

study in the rat. The teratogenicity

studies are designed to evaluate adverse

effects on the developing embryo as a

result of chemical exposure during the

period of organogenesis. Reproduction

studies provide information on effects

from chemical exposure on the

reproductive capability of mating

animals and systemic and

developmental toxicity from in utero

exposure.

In the rat teratology study, reductions

in body weight gain and food

consumption were observed in the dam

at ≥ 100 mg/kg. No teratoganic effects or

any other effects were seen on

pregnancy or fetal parameters except for

the increased incidence of enlarged

thymus, which is a type of variation, at

1,000 mg/kg. The developmental no

observed-adverse-effect level (NOAEL)

was 100 mg/kg.

In the rabbit teratology study, body

weight loss and dramatically reduced

food consumption were observed in the

dam at ≥ 250 mg/kg. No teratogenic

effects or any other effects were seen on

pregnancy or fetal parameters except for

the increase in skeletal anomaly of fused

sternebrae-3 and -4 at the top dose level

of 500 mg/kg. This finding is regarded

as a marginal effect on skeletal

development that could have resulted

from the 40- to 65% lower food intake

during treatment at this dose level. The

developmental NOAEL was 250 mg/kg.

In the 2–generation rat reproduction

study, body weight gain and food

consumption were decreased at > 750

ppm, especially in females during

lactation. Consequently, the reduced

pup weight gain during lactation (> 750

ppm) and the slight delay in eye

opening (1,500 ppm) are judged to be a

secondary effect of maternal toxicity. No

other fetal effects or any reproductive

changes were noted. The low

developmental NOAEL, 50 ppm (5 mg/

kg), seen in this study was probably due

to the lack of intermediate dose levels

between 50 and 750 ppm. Based on an

evaluation of the dose-response

relationship for pup weight at 750 ppm

and 1,500 ppm, the NOAEL should have

been nearly ten-fold higher if such a

dose was available.

Based on all these teratology and

reproduction studies, the lowest NOAEL

for developmental toxicity is 5 mg/kg

while the lowest NOAEL in the

subchronic and chronic studies is 2.5

2952 Federal Register / Vol. 65, No. 12 / Wednesday, January 19, 2000 / Notices

mg/kg/day (from the rat chronic study).

Therefore, no additional sensitivity for

infants and children to trifloxystrobin is

suggested by the data base.

iv. Subchronic toxicity. In subchronic

studies, several mortality related

changes were reported for the top dose

in dogs (500 mg/kg) and rats (800 mg/

kg). At these dose levels, excessive

toxicity has resulted in body weight loss

and mortality with the associated and

nonspecific changes in several organs

(such as atrophy in the thymus,

pancreas, bone marrow, lymph node,

and spleen) which are not considered

specific target organs for the test

compound. In the dog, specific effects

were limited to hepatocellular

hypertrophy at 150 mg/kg and

hyperplasia of the epithelium of the gall

bladder at 500 mg/kg. Target organ

effects in the rat were noted as

hepatocellular hypertrophy (≥ 200 mg/

kg) and the related liver weight increase

(≥ 50 mg/kg). In the mouse, target organ

effects included single cell necrosis (300

mg/kg) and hypertrophy (1,050 mg/kg)

in the liver and extramedullary

hematopoiesis (≥ 300 mg/kg) and

hemosiderosis in the spleen (1,050 mg/

kg).

In general, definitive target organ

toxicity, mostly in the liver, was seen at

high feeding levels of over 100 mg/kg

for an extended treatment period. At the

lowest observed adverse effect level, no

serious toxicity was observed other than

mostly non-specific effects including a

reduction in body weight and food

consumption or liver hypertrophy.

5. Chronic toxicity. The liver appears

to be the major primary target organ

based on the chronic studies conducted

in mice, rats, and dogs. It was identified

as a target organ in both the mouse and

the dog studies with trifloxystrobin.

However, no liver effect was seen in the

chronic rat study which produced the

lowest NOAEL of 2.5 mg/kg based on

reduced body weight gain and food

consumption seen at higher dose levels.

The compound did not cause any

treatment-related increase in general

tumor incidence, any elevated incidence

of rare tumors, or shortened time to the

development of palpable or rapidly

lethal tumors in the 18–month mouse

and the 24–month rat studies. Dosages

in both studies were sufficient for

identifying a cancer risk. In the absence

of carcinogenicity, Novartis believes

that a Reference Dose (RfD) approach is

appropriate for quantitation of human

risks.

6. Animal metabolism.

Trifloxystrobin is moderately absorbed

from the gastrointestinal tract of rats and

is rapidly distributed. Subsequent to a

single oral dose, the half life of

elimination is about 2 days and

excretion is primarily via bile.

Trifloxystrobin is extensively

metabolized by the rat into about 35

metabolites, but the primary actions are

on the methyl ester (hydrolysis into an

acid), the methoxyimino group (Odemethylation), and the methyl side

chain (oxidation to a primary alcohol).

Metabolism is dose dependent as it was

almost complete at low doses but only

about 60% complete at high doses.

In the goat, elimination of orally

administered trifloxystrobin is primarily

via the feces. The major residues were

the parent compound and the acid

metabolite (CGA–321113) plus its

conjugates. In the hen, trifloxystrobin is

found as the major compound in tissues

and in the excreta, but hydroxylation of

the trifluormethyl-phenyl moiety and

other transformations, including methyl

ester hydrolysis and demethylation of

the methoxyimino group, are also seen.

In conclusion, the major pathways of

metabolism in the rat, goat, and hen are

the same.

7. Metabolite toxicology. Metabolism

of trifloxystrobin has been well

characterized in plants, soil, and

animals. In plants and soil,

photolytically induced isomerization

results in a few minor metabolites not

seen in the rat; however, most of the

applied materials remained as parent

compound as shown in the apple and

cucumber studies. All quantitatively

major plant and/or soil metabolites were

also seen in the rat. The toxicity of the

major acid metabolite, CGA–321113

(formed by hydrolysis of the methyl

ester), has been evaluated in cultured rat

hepatocytes and found to be 20-times

less cytotoxic than the parent

compound. Additional toxicity studies

were conducted for several minor

metabolites seen uniquely in plants

and/or soil. The studies indicate that

these metabolites, including CGA–

357261, CGA–373466, and NOA–

414412, are not mutagenic to bacteria

and are of low acute toxicity (LD50 >

2,000 mg/kg). In conclusion, the

metabolism and toxicity profiles

support the use of an analytical

enforcement method that accounts for

parent trifloxystrobin.

8. Endocrine effects. Trifloxystrobin

does not belong to a class of chemicals

known for having adverse effects on the

endocrine system. Developmental

toxicity studies in rats and rabbits and

reproduction study in rats gave no

indication that trifloxystrobin might

have any effects on endocrine function

related to development and

reprodufftion. The subchronic and

chronic studies also showed no

evidence of a long-term effect related to

the endocrine system.

9. Endocrine disruption. CGA–279202

does not belong to a class of chemicals

known for having adverse effects on the

endocrine system. Developmental

toxicity studies in rats and rabbits and

reproduction study in rats gave no

indication that CGA–279202 might have

any effects on endocrine function

related to development and

reproduction. The subchronic and

chronic studies also showed no

evidence of a long-term effect related to

the endocrine system.

C. Aggregate Exposure

1. Dietary Exposure— i. Food. Dietary

exposure was calculated using field trial

residues generated at the maximum

label rate and minimum preharvest

interval. Chronic exposure was

calculated by taking the mean value of

the field trial values, and acute exposure

was calculated by using the entire

residue distribution in a Monte Carlo

analysis. The resulting acute and

chronic exposure estimates

demonstrated negligible exposure.

Using the chronic toxicological

endpoint (rat feeding study), the subpopulation with the highest predicted

exposure was non-nursing infants (< 1

year old) with 1.3% of the reference

dose. Acute exposure for the most

exposed sub-population, non-nursing

infants (< 1 year old), was 2.1% of the

acute reference dose at the 99.9th

pecentile. These results demonstrate a

very large margin of safety for the use

of trifloxystrobin on crops.

ii. Drinking water exposure— a.

estimated surface drinking water

concentration. The generic expected

environmental concentration (GENEEC)

estimated surface water concentrations

for the proposed Flint and Compass

uses contributed little to the overall

exposure. These estimated

concentrations were not adjusted for the

estimated market share or percentage of

use area. The two highest day–56

estimated environmetal concentration

(EEC) values were 0.06 parts per billion

(ppb) and 0.05 ppb provided by the

Compass turf and ornamental uses,

respectively. According to the EPA

‘‘OPP’s Interim Approach for

Addressing Drinking Water Exposure,’’

the average day–56 value is divided by

three when correcting for

overestimation of the GENEEC model.

This was applied to the ornamental use

and the resulting potential exposure via

surface water was 0.05 ppb / 3 = 0.017

ppb. The EPA has accepted that the

average day–56 EEC value is divided by

six in the case when the product is

applied to turf and accounts for the

Federal Register / Vol. 65, No. 12 / Wednesday, January 19, 2000 / Notices 2953

effects of grass/turf in decreasing runoff

(EPA, 1998, EPA–730–F–97–002, PB97–

137806, page 15). This division by six

was used to calculate the potential

exposure via surface water from the

Compass turf application, 0.06 ppb / 6

= 0.010 ppb. Therefore, the highest

potential exposure to trifloxystrobin

from surface water is from the Compass

ornamental use, 0.017 ppb.

b. Estimated ground water

concentrations. The screening

concentration in ground water (SCIGROW) estimated ground water

concentrations for the proposed Flint

and Compass uses also contributed little

to the overall exposure. The estimated

concentrations were not adjusted for the

estimated market share or percentage of

use area. In each use scenario, the

concentration of trifloxystrobin in

ground water was predicted to be below

1 part per trillion. The highest estimated

concentration of trifloxystrobin in the

ground water was 0.000587 ppb

provided by the Compass turf use.

c. Drinking water levels of concern—

acute exposure. The estimated

maximum concentrations of

trifloxystrobin in surface water at Peak

Day–0 was 2.48 ppb (GENEEC) and

0.000587 ppb in ground water (SCIGROW). The acute drinking water level

of concentration (DWLOC) values were

calculated and compared to these

estimated water concentrations. Per EPA

preference, the 10–day multiple dosing

rat teratology study defined the acute

NOAEL at 10 mg/kg/day.

From the acute dietary exposure

analysis, the lowest Margin of Exposure

(MOE) from the use of trifloxystrobin

was 1,960 at the 99.9th percentile for the

U.S. population and all population

subgroups. This indicates a food

exposure of less than 0.0051 mg/kg/day

for all populations. Based on the EPA’s

‘‘Interim Guidance for Conducting

Drinking Water Exposure and Risk

Assessments’’ document (draft 12/2/97),

acute drinking water levels of concern

(DWLOCacute) were calculated for

trifloxystrobin. The lowest acceptable

Margin of Exposure (MOE) for any

pesticide is 100. This value was used in

the DWLOC calculations as a

conservative approach. Based on this

analysis, trifloxystrobin estimated

surface water (2.48 ppb) and ground

water concentrations (0.000587 ppb) do

not exceed the calculated acute DWLOC

values (3,497, 3,496, 2,997, 997).

Therefore, trifloxystrobin exposures

would not exceed the exposure

allowable by the risk cup.

d. Chronic exposure. The estimated

maximum concentrations of

trifloxystrobin in surface water at Day–

56/3 was 0.017 ppb (GENEEC) and

0.000587 ppb in ground water (SCIGROW). The chronic DWLOC values

were calculated and compared to these

estimated water concentrations. The

chronic reference dose for

trifloxystrobin is 0.025 mg/kg body wt/

day, based upon the findings in the rat

chronic toxicity study. From the chronic

dietary exposure analysis, an exposure

estimate of 0.000140 mg/kg body wt/day

was determined for the U.S. population

and > 0.00032 for all subgroups. Using

this information, chronic drinking water

levels of concern (DWLOCchronic) were

calculated for trifloxystrobin. The

trifloxystrobin estimated ground water

(0.000587 ppb) and surface water (0.017

ppb) concentrations do not exceed the

calculated chronic DWLOC values (872,

870, 746, 247). Therefore, trifloxystrobin

exposures would not exceed the

exposure allowable by the risk cup.

2. Non-dietary exposure. Non-dietary

exposure to trifloxystrobin is considered

negligible as the chemical is intended

primarily for commercial and

agricultural use. Post-application reentry exposure to homeowners from

professional use on residential

ornamentals is considered negligible.

For workers handling this chemical,

acceptable margins of exposure (in the

range of thousands) have been obtained

for both acute and chronic scenarios.

D. Cumulative Risk

Consideration of a common

mechanism of toxicity is not appropriate

at this time since there is no information

to indicate that toxic effects produced

by trifloxystrobin would be cumulative

with those of any other types of

chemicals. Furthermore, the

oximinoacetate is a new type of

fungicide and no compound in this

general chemical class currently has a

significant market share. Consequently,

Novartis is considering only the

potential exposure to trifloxystrobin in

its aggregate risk assessment.

E. Safety Determination

1. U.S. population. Using the

conservative exposure assumptions

described above and based on the

completeness and reliability of the

toxicity data base for trifloxystrobin,

Novartis has calculated aggregate

exposure levels for this chemical. The

calculation shows that only 0.5% of the

RfD will be utilized for the U.S.

population based on chronic toxicity

endpoints. EPA generally has no

concern for exposures below 100

percent 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. Novartis concludes

that there is a reasonable certainty that

no harm will result from aggregate

exposure to trifloxystrobin residue.

2. Infants and children.

Developmental toxicity, manifested as

reduced weaning pup weight, enlarged

thymus, or fused sternabrae, was

observed in the teratology study and 2–

generation rat reproduction studies at

maternally toxic doses. All of these

findings are judged to be non-specific,

secondary effects of maternal toxicity.

The lowest NOAEL for developmental

toxicity was established in the rat

reproduction study at 5 mg/kg, a level

that is likely to be an overly low

estimate (as a result of dose gap) but is

still higher than the chronic NOAEL of

2.5 mg/kg on which the RfD is based.

Using the same conservative exposure

assumptions as employed for the

determination in the general population,

Novartis has calculated that the percent

of the RfD that will be utilized by

aggregate exposure to residues of

trifloxystrobin is only 2.1% for nonnursing infants (> l year old) (the most

impacted sub-population). Therefore,

based on the completeness and

reliability of the toxicity data base and

the conservative exposure assessment,

Novartis concludes that there is a

reasonable certainty that no harm will

result to infants and children from

aggregate exposure to trifloxystrobin

residues.

F. International Tolerances

No Codex MRL’s have been

established for residues of

trifloxystrobin. Flint has been registered

on pome fruit in Switzerland, and

Stratego (trifloxystrobin +

propiconazole) has been registered on

cereals in Switzerland.

[FR Doc. 00–1214 Filed 1–18–00; 8:45 am]

BILLING CODE 6560–50–F

ENVIRONMENTAL PROTECTION

AGENCY

[FRL–6526–1]

Proposed Prospective Purchaser

Agreement Pursuant to the

Comprehensive Environmental

Response, Compensation and Liability

Act of 1980 (CERCLA), as Amended by

the Superfund Amendments and

Reauthorization Act, OronogoDuenweg Mining Belt Superfund Site,

Jasper County, Missouri

AGENCY: Environmental Protection

Agency.

ACTION: Notice; request for public

comment.