[Federal Register Volume 60, Number 13 (Friday, January 20, 1995)]
[Rules and Regulations]
[Pages 4091-4093]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-1498]



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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[PP 1F4013/R2101; FRL-4930-9]
RIN 2070-AB78


Pesticide Tolerances for Imazethapyr

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This rule establishes tolerances for the sum of the residues 
of the herbicide imazethapyr, 2-[4,5-dihydro-4-methy1-4-(1-
methylethyl)-5-oxo-1H-imidazo1-2-yl]-5-ethy1-3-pyridine carboxylic 
acid, as its ammonium salt and its metabolite, 2-[4,5-dihydro-4-methyl-
4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-(1-hydroxyethyl)-3-pyridine 
carboxylic acid, both free and conjugated, in or on 
[[Page 4092]] alfalfa, forage and hay at 3.0 parts per million (ppm). 
The American Cyanamid Co. requested this regulation that establishes 
the maximum permissible level for residues of the herbicide in or on 
alfalfa.

EFFECTIVE DATE: This regulation becomes effective January 20, 1995.

ADDRESSES: Written objections and hearing requests, identified by the 
document control number, [PP 1F4013/R2101], may be submitted to: 
Hearing Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M 
St., SW., Washington, DC 20460. A copy of objections and hearing 
requests filed with the Hearing Clerk should be identified by the 
document control number and submitted to: Public Response and Program 
Resources Branch, Field Operations Division (7506C), Office of 
Pesticide Programs, Environmental Protection Agency, 401 M St., SW., 
Washington, DC 20460. In person, bring copy of objections and hearing 
request to: Rm. 1132, CM #2, 1921 Jefferson Davis Hwy., Arlington, VA 
22202. Fees accompanying objections shall be labeled ``Tolerance 
Petition Fees'' and forwarded to: EPA Headquarters Accounting 
Operations Branch, OPP (Tolerance Fees), P.O. Box 36277M, Pittsburgh, 
PA 15251.

FOR FURTHER INFORMATION CONTACT: By mail: Robert J. Taylor, Product 
Manager (PM) 25, Registration Division (7505C), Environmental 
Protection Agency, 401 M St., SW., Washington, DC 20460. Office 
location and telephone number: Rm. 245, CM #2, 1921 Jefferson Davis 
Hwy., Arlington, VA 22202, (703) 305-6800.

SUPPLEMENTARY INFORMATION: EPA issued a notice, published in the 
Federal Register of March 11, 1992 (57 FR 8658), which announced that 
the American Cyanamid Co., P.O. Box 400, Princeton, NJ 08540, had 
submitted pesticide petition (PP) 1F4013 to EPA proposing that 40 CFR 
part 180 be amended by establishing a tolerance under section 408 of 
the Federal Food, Drug and Cosmetic Act, 21 U.S.C. 346a, for the 
combined residues of the herbicide imazethapyr, 2-[4,5-dihydro-4-
methyl-4-(1-methylethyl)-5-oxo-1H-imidazo1-2-y1]-5-ethy1-3-pyridine-
carboxylic acid, as its ammonium salt and the metabolite, 2-[4,5-
dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-(1-
hydroxyethyl)-3-pyridine carboxylic acid, both free and conjugated, in 
or on alfalfa, forage and hay at 3.0 ppm.
    There were no comments or requests for referral to an advisory 
committee received in response to the notice of filing. The data 
submitted in the petition and other relevant material have been 
evaluated. The toxicology data listed below were considered in support 
of the tolerance.
    1. Several acute toxicology studies placing technical-grade 
imazethapyr in Toxicity Category III.
    2. An 18-month carcinogenicity study with mice fed diets containing 
0, 1,000, 5,000, or 10,000 ppm with no carcinogenic effects observed 
under the conditions of the study at levels up to and including 10,000 
ppm (1,500 mg/ kg/day) (highest dose tested [HDT]), a systemic no-
observed-effect level (NOEL) of 5,000 ppm (750 mg/kg/day), and a 
systemic LOEL of 10,000 ppm (1,500 mg/kg/day), based on decreased body 
weight gain in both sexes.
    3. A 2-year chronic toxicity/carcinogenicity study in rats fed 
diets containing 0, 1,000, 5,000, or 10,000 ppm with no carcinogenic 
effects observed under the conditions of the study at levels up to and 
including 10,000 ppm (500 mg/kg/day [HDT]) and a systemic NOEL of 
10,000 ppm (500 mg/kg/day [HDT]).
    4. A l-year feeding study in dogs fed diets containing 0, 1,000, 
5,000, or 10,000 ppm with a NOEL of 1,000 ppm (25 mg/kg/day and a LOEL 
of 5,000 ppm (125 mg/kg/day), based on decreased packed cell volume, 
hemoglobin, and erythrocytes in females.
    5. A developmental toxicity study in rats fed dosage levels of 0, 
125, 375, and 1,125 mg/kg/day, with a maternal toxicity NOEL of 375 mg/
kg/day and a LOEL of 1,125 mg/kg/day (clinical signs of toxicity) and a 
developmental toxicity NOEL of greater than 1,125 mg/kg/day (HDT).
    6. A developmental toxicity study in rabbits fed dosage levels of 
0, 100, 300, and 1,000 mg/kg/day with a maternal toxicity NOEL of 300 
mg/kg/day and a LOEL of 1,000 mg/kg/day (death) and a developmental 
toxicity NOEL of greater than 1,000 mg/kg/day (HDT).
    7. A two-generation reproduction study in rats fed dietary levels 
of 0, 1,000, 5,000, or 10,000 ppm with a NOEL for systemic and 
reproductive effects of 10,000 ppm (500 mg/kg/day [HDT]).
    8. A mutagenic test with Salmonella typhimurium (negative); an in 
vitro chromosomal aberration test in Chinese hamster ovary cells 
(positive without metabolic activation but at dose levels that were 
toxic to the cells and negative with metabolic activation); an in vivo 
chromosomal aberration test in rat bone marrow cells (negative); an 
unscheduled DNA synthesis study in rat hepatocytes (negative).
    Based on the NOEL of 25 mg/kg bwt/day in the 1-year dog feeding 
study, and using a hundredfold uncertainty factor, the acceptable daily 
intake (ADI) for imazethapyr is calculated to be 0.25 mg/kg bwt/day. 
The theoretical maximum residue contrbution (TMRC) is 0.000100 mg/kg 
bwt/day for existing tolerances for the overall U.S. population. The 
current action will not increase the TMRC since no finite residues of 
imazethapyr are expected from meat and milk derived from animals 
consuming treated alfalfa. This tolerance and previously established 
tolerances utilize a total of 0.05 percent of the ADI for the overall 
U.S. population. For U.S. subgroup populations, nonnursing infants and 
children aged 1 to 6, the previously established tolerances utilize a 
total of 0.16 percent of the ADI.
    A maximum Tolerated Dose (MTD) or Limit Dose (20,000 ppm) was not 
evaluated in the chronic toxicity/ carcinogenicity study with rats. 
However, the highest dose tested was within 50 percent of the dose 
level necessary for an adequate carcinogenicity study in rats (20,000 
ppm or 1,000 mg/kg/day); this chemical is structurally similar to two 
other pesticides (Scepter and Assert) that were not carcinogenic in 
rats or mice, and the genetic toxicity studies were negative for 
imazethapyr. For these reasons, no further carcinogenicity testing is 
required.
    Although an analytical method is available for imazethapyr on 
alfalfa (confirmed by EPA), the Agency has requested that the 
petitioner rewrite the primary enforcement procedure to include an 
alternate CE buffer system as the confirmatory step and the petitioner 
has agreed. This pesticide is useful for the purposes for which the 
tolerances are sought. The nature of the residues is adequately 
understood for the purposes of establishing these tolerances. Adequate 
analytical methodology, capillary electrophoresis, is available for 
enforcement purposes. Because of the long lead time from establishing 
this tolerance to publication, enforcement methodology is being made 
available in the interim to anyone interested in pesticide enforcement 
when requested by mail from: Calvin Furlow, Public Response and Program 
Resources Branch, Field Operations Division (7506C), Office Pesticide 
Programs, Environmental Protection Agency, 401 St., SW., Washington, DC 
20460. Office location and telephone number: Rm. 1130A, CM #2, 1921 
Jefferson Davis Hwy., Arlington, 22202.
    There are currently no actions pending against the registration of 
this chemical. There is no expectation of residue occurring in meat, 
milk, poultry, [[Page 4093]] or eggs from this tolerance. Based on the 
data and information submitted above, the Agency has determined that 
the establishment of tolerances by amending 40 CFR part 180 will 
protect the public health. Therefore, EPA is establishing the tolerance 
as described below.
    Any person adversely affected by this regulation may, within 30 
days after the date of publication in the Federal Register, file 
written objections with the Hearing Clerk, Environmental Protection 
Agency, at the address given above. 40 CFR 178.20. A copy of the 
objections and/or hearing requests filed with the Hearing Clerk should 
be submitted to the OPP docket for this rulemaking. The obctions 
submitted must specify the provisions of the regulation deemed 
objectionable and the grounds for the objection. 40 CFR 178.25. Each 
objection must be accompanied by the fee prescribed by 40 CFR 
180.33(i). If a hearing is requested, the objections must include a 
statement of the factual sue(s) on which a hearing is requested, the 
requestor's intentions on each issue, and a summary of any evidence 
relied upon by the objector. 40 CFR 178.27. A request for hearing will 
be granted if the Administrator determines at the material submitted 
shows the following: There is a genuine and substantial issue of fact; 
there is a reasonable possibility that available evidence identified by 
the requestor would, if established, resolve one or more of such issues 
in favor of the requestor, taking into account uncontested aims or 
facts to the contrary; and resolution of the factual issue(s) in the 
manner sought by the requestor would be adequate to justify the action 
requested. 40 CFR 178.32.
    Under Executive Order 12866 (58 FR 51735, Oct. 4, 1993), the Agency 
must determine whether the regulatory action is ``significant'' and 
therefore subject to review by the Office of Management and Budget 
(OMB) and the requirements of the Executive Order. Under section 3(f), 
the order defines a ``significant regulatory action'' as an action that 
is likely to result in a rule (1) having an annual effect on the 
economy of $100 million or more, or adversely and materially affecting 
a sector the economy, productivity, competition, jobs, the environment, 
public health or safety, or State, local, or tribal governments or 
communities (also referred to as ``economically significant''); (2) 
creating serious inconsistency or otherwise interfering with action 
taken or planned by another Agency; (3) materially altering the 
budgetary impacts of entitlement, grants, user fees, or loan programs 
or the rights and obligations of recipients thereof; or (4) raising 
novel legal or policy issues arising out of legal mandates, the 
President's priorities, or the principles set forth in this Executive 
Order.
    Pursuant to the terms of the Executive Order, EPA has determined 
that this rule is not ``significant'' and is therefore not subject to 
OMB review. Pursuant to the requirements of the Regulatory Flexibility 
Act (Pub. L. 96-354, 94 Stat. 1164, 5 U.S.C. 601-612), the 
Administrator has determined that regulations establishing new 
tolerances or raising tolerance levels or establishing exemptions from 
tolerance requirements do not have a significant economic impact on a 
substantial number small entities. A certification statement to this 
effect was published in the Federal Register of May 4, 1981 (46 FR 
24950).

List of Subjects in 40 CFR Part 180

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Pesticides and pests, Reporting and 
recordkeeping requirements.

    Dated: January 9, 1995.

Stephen L. Johnson,
Director, Registration Division, Office of Pesticide Programs.

    Therefore, 40 CFR part 180 is amended as follows:

PART 180--[AMENDED]

    1. The authority citation for part 180 continues to read as 
follows:

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

    2. In Sec. 180.447, paragraph (b) is amended by revising the table 
therein, to read as follows:


Sec. 180.447 Imazethapyr, ammonium salt; tolerances for residues.

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    (b) *  *  *

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                                                              Parts per 
                         Commodity                             million  
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Alfalfa, forage............................................          3.0
Alfalfa, hay...............................................          3.0
Peanuts....................................................          0.1
Peanuts, hulls.............................................          0.1
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[FR Doc. 95-1498 Filed 1-19-95; 8:45 am]
BILLING CODE 6560-50-F