Federal Register / Vol. 62, No. 209 / Wednesday, October 29, 1997 / Notices 56171

protected by shoes and socks. Further,

based on the limited frequency of use on

turfgrass, this non-food use is not likely

to result in potential chronic exposure

and thus should not be factored into a

chronic exposure assessment. Exposures

resulting from application to

ornamentals is also anticipated to be

negligible because consumers will not

be in contact with treated plants until

after the foliage is dry.

E. Endocrine Disruptors

Auxein has no information to suggest

that GABA will adversely affect the

immune or endocrine systems.

F. Safety Considerations

GABA is naturally-occurring in food

and is a pharmaceutical agent.

Incremental exposure to GABA resulting

from the application of AuxiGro is

minimal to negligible. Considering the

negligible contributions of GABA to the

environment resulting from the

application of AuxiGro, the

biochemical’s prevalence in nature, and

its role and abundance in foods, GABA

does not pose a human health risk.

G. Analytical Method

An analytical method using High

Performance Liquid Chromatography

(HPLC) for determining the GABA

content in AuxiGro, the end-use

product, is available. However, because

GABA is found naturally in plants,

residue analysis would not yield

meaningful results, i.e., the analysis

would not discern whether the source of

GABA was the plant or the product

treatment.

H. Codex Maximum Residue Level

There are no CODEX tolerances or

international tolerance exemptions for

GABA.

[FR Doc. 97–28664 Filed 10–28–97; 8:45 am]

BILLING CODE 6560–50–F

ENVIRONMENTAL PROTECTION

AGENCY

[PF–775; FRL–5752–2]

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–775, must be

received on or before November 28,

1997.

ADDRESSES: By mail submit written

comments to: Public Information and

Records Integrity Branch (7502C),

Information Resources and Services

Division, 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: oppdocket@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

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: By

mail: Elizabeth Haeberer, Registration

Division (7505C), Office of Pesticide

Programs, Environmental Protection

Agency, 401 M St., SW., Washington,

DC 20460. Office location and telephone

number: Rm. 250, CM #2, 1921 Jefferson

Davis Highway, Arlington, VA 22202,

(703) 308–2891; e-mail:

haeberer.elizabeth@epamail.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–775]

(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. Comment and data will

also be accepted on disks in

Wordperfect 5.1 file format or ASCII file

format. All comments and data in

electronic form must be identified by

the docket number [PF–775] and

appropriate petition number. Electronic

comments on this 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: October 16, 1997.

James Jones,

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.

Gustafson, Inc.

PP 4F4415

EPA has received a pesticide petition

(PP 4F4415) from Gustafson, Inc., 1400

Preston Road, Suite 400, Plano, Texas

75093, proposing pursuant to section

408(d) of the Federal Food, Drug and
56172 Federal Register / Vol. 62, No. 209 / Wednesday, October 29, 1997 / Notices

Cosmetic Act, 21 U.S.C. 346a(d), to

amend 40 CFR Part 180 to make the

time limited tolerances permanent by

establishing a tolerance for residues of

imidacloprid in or on the raw

agricultural commodity sorghum grain

0.05 parts per million (ppm), forage 0.10

ppm, and stover 0.10 ppm. The

proposed analytical method involves

homogenization, filtration, partition and

cleanup with analysis by high

performance liquid chromatography

using UV detection’’ for determining

residues is a common moiety method

for imidacloprid and its metabolites

containing the 6-chloro-pyridinyl

moiety using oxidation, derivatization,

and analysis by capillary gas

chromatography with a mass-selective

detector. 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 imidacloprid in plants is adequately

understood for the purposes of these

tolerances. The residues of concern are

combined residues of imidacloprid and

its metabolites containing the 6-chloropyridinyl moiety, all calculated as

imidacloprid.

2. Analytical method. The analytical

method is a common moiety method for

imidacloprid and its metabolites

containing the 6-chloro-pyridinyl

moiety using a permanganate oxidation,

silyl derivatization, and capillary GCMS selective ion monitoring. This

method has successfully passed a

petition method validation in EPA labs.

There is a confirmatory method

specifically for imidacloprid and several

metabolites utilizing GC/MS and HPLCUV which has been validated by the

EPA as well. Imidacloprid and its

metabolites are stable for at least 24

months in the commodities when

frozen.

3. Magnitude of residues. Sorghum

seed was treated with imidacloprid,

formulated as Gaucho 480 FS at a rate

of 8.0 oz. ai/cwt seed. Field trials were

conducted at fifteen locations: Arkansas,

California, Colorado (two locations),

Kansas (two locations), Louisiana,

Missouri, Nebraska (two locations),

North Carolina, Oklahoma, South

Dakota, and Texas (two locations). The

sorghum seed was planted and the

RACs were harvested at the appropriate

growth stages. Residue levels in the

sorghum grain were less than 0.05 ppm.

Maximum residues were 0.058 ppm in

the forage and 0.065 ppm in the stover.

These residue data support tolerances of

0.05 ppm for sorghum grain, 0.10 ppm

for sorghum forage, and 0.10 ppm for

sorghum stover. A processing study was

submitted with this petition. No

tolerances were required for processed

fractions of sorghum grain since

residues in the sorghum grain when

treated at the 2X rate (which is higher

than the maximum theoretical

concentration factor of 1.6X) were less

than the limit of quantitation (LOQ) of

0.05 ppm.

B. Toxicological Profile

1. Acute toxicity. The acute oral LD50

values for imidacloprid technical ranged

from 424 to 475 mg/kg bwt in the rat.

The acute dermal LD50 was greater than

5,000 mg/kg in rats. The 4-hour

inhalation LC50 was less than 69 mg/m3

air (aerosol). Imidacloprid was not

irritating to rabbit skin or eyes.

Imidacloprid did not cause skin

sensitization in guinea pigs.

2. Genotoxicity. Extensive

mutagenicity studies conducted to

investigate point and gene mutations,

DNA damage and chromosomal

aberration, both using in vitro and in

vivo test systems show imidacloprid to

be non-genotoxic.

3. Reproductive and developmental

toxicity. A 2-generation rat reproduction

study gave a no-observed-effect level

(NOEL) of 100 ppm (8 mg/kg/bwt). Rat

and rabbit developmental toxicity

studies were negative at doses up to 30

mg/kg/bwt and 24 mg/kg/bwt,

respectively.

4. Subchronic toxicity. Ninety-day

feeding studies were conducted in rats

and dogs. The NOELs for these tests

were 14 mg/kg/bwt/day (150 ppm) and

5 mg/kg/bwt/day (200 ppm), for the rat

and dog studies, respectively.

5. Chronic toxicity. A 2-year rat

feeding/carcinogenicity study was

negative for carcinogenic effects under

the conditions of the study and had a

NOEL of 100 ppm (5.7 mg/kg/bwt in

males and 7.6 mg/kg/bwt in females for

noncarcinogenic effects that included

decreased body weight gain in females

at 300 ppm and increased thyroid

lesions in males at 300 ppm and females

at 900 ppm. A 1-year dog feeding study

indicated a NOEL of 1,250 ppm (41 mg/

kg/bwt). A 2-year mouse carcinogenicity

study that was negative for carcinogenic

effects under conditions of the study

and that had a NOEL of 1,000 ppm (208

mg/kg/day).

Imidacloprid has been classified

under ‘‘Group E’’ (no evidence of

carcinogenicity) by EPA’s OPP/HED’s

Reference Dose (RfD) Committee. There

is no cancer risk associated with

exposure to this chemical. The reference

dose (RfD) based on the 2-year rat

feeding/carcinogenic study with a NOEL

of 5.7 mg/kg/bwt and 100-fold

uncertainty factor, is calculated to be

0.057 mg/kg/bwt. The theoretical

maximum residue contribution (TMRC)

from published uses is 0.008358 mg/kg/

bwt/day utilizing 14.7% of the RfD.

6. Animal metabolism. The nature of

the imidacloprid residue in animals is

adequately understood. The residues of

concern are combined residues of

imidacloprid and its metabolites

containing the 6-chloropyridinyl

moiety, all calculated as imidacloprid.

7. Metabolite toxicology. Metabolites,

at the levels reported, are not

toxicologically significant. No separate

regulation of metabolites is warranted,

and there is no scientific objection to

the tolerance expression being for the

combined residues of imidacloprid and

its metabolites containing the 6-

chloropyridinyl moiety.

C. Aggregate Exposure

1. Dietary exposure. The EPA has

determined that the reference dose (RfD)

based on the 2-year rat feeding/

carcinogenicity study with a NOEL of

5.7 mg/kg/bwt and 100-fold uncertainty

factor, is calculated to be 0.057 mg/kg/

bwt. As published in the Federal

Register June 12, 1996 (61 FR 29674)

(petition to establish tolerances on leafy

green vegetables (PP 5F4522/R2237)),

the theoretical maximum residue

contribution (TMRC) from published

uses is 0.008358 mg/kg/bwt utilizing

14.7% of the RfD for the general

population. For the most highly exposed

subgroup in the population, nonnursing infants (less than 1-year old),

the TMRC for the published tolerances

is 0.01547 mg/kg/day. This is equal to

27.1% of the RfD. The December 1, 1994

Federal Register (59 FR 61552)

indicates that the tolerances for

sorghum contribute 0.000001188 mg/kg/

bwt/day which represents 0.002% of the

RfD which is included in the total

values published in the June 12, 1996

Federal Register. Therefore, dietary

exposure from the existing uses

including the current temporary

tolerances will not exceed the reference

dose for any subpopulation (including

infants and children).

2. Food. Dietary exposure from the

existing uses including the current

temporary tolerances will not exceed

the reference dose for any

subpopulation (including infants and

children).

3. Drinking water. Although the

various imidacloprid labels contain a
Federal Register / Vol. 62, No. 209 / Wednesday, October 29, 1997 / Notices 56173

statement that this chemical

demonstrates the properties associated

with chemicals detected in

groundwater, the Registrant is not aware

of imidacloprid being detected in any

wells, ponds, lakes, streams, etc. from

its use in the United States. In studies

conducted in 1995, imidacloprid was

not detected in seventeen wells on

potato farms in Quebec, Canada. In

addition, groundwater monitoring

studies are currently underway in

California and Michigan. Therefore,

contributions to the dietary burden from

residues of imidacloprid in water would

be inconsequential.

4. Non-dietary exposure— a.

Residential turf. Bayer Corporation has

conducted an exposure study to address

the potential exposures of adults and

children from contact with imidacloprid

treated turf. The population considered

to have the greatest potential exposure

from contact with pesticide treated turf

soon after pesticides are applied are

young children. Margins of safety (MOS)

of 7,587 - 41,546 for 10 year old

children and 6,859 - 45,249 for 5 year

old children were estimated by

comparing dermal exposure doses to the

imidacloprid no-observable effect level

of 1,000 mg/kg/day established in a 15-

day dermal toxicity study in rabbits.

The estimated safe residue levels of

imidacloprid on treated turf for 10 year

old children ranged from 5.6 - 38.2 g/

cm2 and for 5 year old children from 5.1

- 33.3 g/cm2. This compares with the

average imidacloprid transferable

residue level of 0.080 g/cm2 present

immediately after the sprays have dried.

These data indicate that children can

safely contact. Bayer Corporation has

conducted an exposure imidaclopridtreated turf as soon after application as

the spray has dried.

b. Termiticide. Imidacloprid is

registered as a termiticide. Due to the

nature of the treatment for termites,

exposure would be limited to that from

inhalation and was evaluated by EPA’s

Occupational and Residential Exposure

Branch (OREB) and Bayer Corporation.

Data indicate that the Margins of Safety

for the worst case exposures for adults

and infants occupying a treated building

who are exposed continuously (24

hours/day) are 8.0 x 107 and 2.4 x 108,

respectively, and exposure can thus be

considered negligible.

c. Tobacco smoke. Studies have been

conducted to determine residues in

tobacco and the resulting smoke

following treatment. Residues of

imidacloprid in cured tobacco following

treatment were a maximum of 31 ppm

(7 ppm in fresh leaves). When this

tobacco was burned in a pyrolysis study

only two percent of the initial residue

was recovered in the resulting smoke

(main stream plus side stream). This

would result in an inhalation exposure

to imidacloprid from smoking of

approximately 0.0005 mg per cigarette.

Using the measured subacute rat

inhalation NOEL of 5.5 mg/m3, it is

apparent that exposure to imidacloprid

from smoking (direct and/or indirect

exposure) would not be significant.

d. Pet treatment. Human exposure

from the use of imidacloprid to treat

dogs and cats for fleas has been

addressed by EPA’s Occupational and

Residential Exposure Branch (OREB)

who have concluded that due to the fact

that imidacloprid is not an inhalation or

dermal toxicant and that while dermal

absorption data are not available,

imidacloprid is not considered to

present a hazard via the dermal route.

D. Cumulative Effects

No other chemicals having the same

mechanism of toxicity are currently

registered, therefore, there is no risk

from cumulative effects from other

substances with a common mechanism

of toxicity.

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, it can be concluded that

total aggregate exposure to imidacloprid

from all current uses including those

currently proposed will utilize little

more than 15% of the RfD for the U.S.

population. 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.

Thus, it can be concluded that there is

a reasonable certainty that no harm will

result from aggregate exposure to

imidacloprid residues.

2. Infants and children. In assessing

the potential for additional sensitivity of

infants and children to residues of

imidacloprid, the data from

developmental studies in both rat and

rabbit and a 2-generation reproduction

study in the rat have been considered.

The developmental toxicity studies

evaluate potential adverse effects on the

developing animal resulting from

pesticide exposure of the mother during

prenatal development. The reproduction

study evaluates effects from exposure to

the pesticide on the reproductive

capability of mating animals through

two generations, as well as any observed

systemic toxicity.

FFDCA Section 408 provides that the

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.

Based on current toxicological data

requirements, the toxicology database

for imidacloprid relative to pre- and

post-natal effects is complete. Further

for imidacloprid, the NOEL of 5.7 mg/

kg/bwt from the 2-year rat feeding/

carcinogenic study, which was used to

calculate the RfD (discussed above), is

already lower than the NOELs from the

developmental studies in rats and

rabbits by a factor of 4.2 to 17.5 times.

Since a 100-fold uncertainty factor is

already used to calculate the RfD, it is

surmised that an additional uncertainty

factor is not warranted and that the RfD

at 0.057 mg/kg/bwt/day is appropriate

for assessing aggregate risk to infants

and children. Using the conservative

exposure assumptions described above,

EPA has concluded that the TMRC from

use of imidacloprid from published uses

is 0.008358 mg/kg/bwt/day utilizing

14.7% of the RfD for the general

population. For the most highly exposed

subgroup in the population, nonnursing infants (less than 1 year old),

the TMRC for the published tolerances

is 0.01547 mg/kg/day. This is equal to

27.1% of the RfD. Therefore, dietary

exposure from the existing uses

including the currently proposed

tolerances will not exceed the reference

dose for any subpopulation (including

infants and children).

F. International Tolerances

No CODEX Maximum Residue Levels

(MRLs) have been established for

residues of imidacloprid on any crops at

this time.

[FR Doc. 97–28663 Filed 10–28–97; 8:45 am]

BILLING CODE 6560–50–F

ENVIRONMENTAL PROTECTION

AGENCY

[PF–771; FRL–5749–7]

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–771, must be

received on or before November 28,

1997.