[Federal Register Volume 59, Number 66 (Wednesday, April 6, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-8104]
[[Page Unknown]]
[Federal Register: April 6, 1994]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[PP3F4177/R2052; FRL-4772-1]
Pesticide Tolerances for Dimethenamid
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes tolerances for residues of the
herbicide, dimethenamid, 2-chloro-N-[(1-methyl-2methoxy)ethyl]-N-(2,4-
dimethyl-thien-3-yl)-acetamide in or on the raw agricultural commodity
(RAC) soybeans at 0.01 parts per million (ppm). This regulation to
establish the maximum permissible level of residues of the herbicide in
or on this commodity was requested in a petition submitted by Sandoz
Agro Inc.
DATES: This regulation becomes effective on April 6, 1994.
ADDRESSES: Written objections and hearing requests, identified by the
document control number, [PP3F4177/R2052], may be submitted to: Hearing
Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M St.,
SW., Washington, DC 20460. A copy of any objection and hearing request
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 (7505C), Office of Pesticide
Programs, Environmental Protection Agency, 401 M St., SW., Washington
DC 20460. In Person, bring a copy of objections and hearing requests
to: Rm 1132, CM #2, 1921 Jefferson Davis Highway, 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 360277M, Pittsburgh, PA 15251.
FOR FURTHER INFORMATION CONTACT: By mail: Cynthia Giles-Parker, Product
Manager (PM) 22, Registration Division, Environmental Protection
Agency, 401 M St., SW., Washington, DC 20460. Office location and
telephone number: Rm. 229, CM #2, 1921 Jefferson Davis Highway,
Arlington, VA 22202, (703-305-5540).
SUPPLEMENTARY INFORMATION: EPA issued a notice published in the Federal
Register on October 21, 1993 (58 FR 54353) which announced that Sandoz
Agro Inc., 1300 East Touhy Avenue, Des Plaines, IL 60018, had submitted
a pesticide petition (PP 3F4177) to EPA requesting that the
Administrator, pursuant to section 408(d) of the Federal Food, Drug,
and Cosmetic Act (FFDCA), 21 U.S.C. 346a(d), establish tolerances for
the residues of the herbicide, dimethenamid, 2-chloro-N-[(1-methyl-2-
methoxy)ethyl]-N-(2,4-dimethyl-thien-3-yl)-acetamide in or on the RAC
soybean grain at 0.01 ppm. The Agency is editorially correcting the RAC
to read soybeans. There were no comments or requests for referral to an
advisory committee received in response to this notice of filing. The
data submitted in the petitions and all other relevant material have
been evaluated. The toxicology data considered in support of the
tolerances include:
1. A rat acute oral study with an LD50 of 2.14 grams (g)/kilogram
(kg), males, 1.30 g/kg females and 1.57 g/kg combined.
2. A 13-week rat feeding study with a no-observed effect level
(NOEL) of 500 ppm (33.5 milligrams (mg)/kg/day for males and 40.1 mg/
kg/day for females).
3. A 13-week dog feeding study with a NOEL of 100 ppm (2.5 mg/kg/
day).
4. A 21 day rabbit dermal study with a NOEL of 50 mg/kg/day with
mild irritant effect at all dose levels.
5. A carcinogenicity study in mice with no carcinogenic effects
observed at any dose level under the conditions of the study and a
systemic NOEL of 300 ppm (40.8 mg/kg/day for males and 40.1 mg/kg/day
for females, based on food consumption) and a systemic lowest effect
level (LEL) of 1,500 ppm (205 mg/kg/day for males and 200 mg/kg/day for
females based on food consumption) based on significantly elevated
liver weights.
6. A rat chronic feeding/carcinogenicity study with a systemic NOEL
of 100 ppm (5 mg/kg/day) and a LEL of 700 ppm (35 mg/kg/day) due to
decreased food efficiency and histopathology findings. Under the
conditions of the study limited evidence of carcinogenicity was
observed based on a statistically significant increasing trend for
benign liver cell tumors in male rats and a statistically significant
increasing trend for ovarian tubular adenomas in female rats. A re-
evaluation of the ovarian neoplasia data indicated that there was no
statistically significant, dose-related, trend in the incidence of
ovarian tumors in female rats. This study is discussed further below.
7. A 1 year dog feeding study with a NOEL of 250 ppm (9.6 mg/kg/
day) and with a LEL = 1,250 ppm (49 mg/kg/day) based on clinical
chemistry and histological changes in liver.
8. A two generation reproduction study in rats with a parental and
reproductive NOEL of 500 ppm (36 mg/kg/day for males and 40 mg/kg/day
for females) and a parental and reproductive LEL of 2,000 ppm (150 mg/
kg/day for males and 160 mg/kg/day for females) based on reduction of
body weight and of food consumption, and increases in liver weights
(parental toxicity), and significant reductions in pup weight during
lactation (reproductive toxicity).
9. A rabbit developmental study with a maternal NOEL of 37.5 mg/kg/
day and a LEL of 75 mg/kg/day based on decreased body weight and food
consumption, and with a developmental NOEL of 75 mg/kg/day and a LEL of
150 mg/kg/day based on a low incidence of abortion/premature delivery
and angulation of the hyoid alae.
10. A rat developmental study with a maternal NOEL of 50 mg/kg/day
and a LEL of 215 mg/kg/day based on excess salivation, increased liver
weight and reduced body weight gain and food consumption, and with a
developmental NOEL of 215 mg/kg/day and a LEL of 425 mg/kg/day based on
increased resorptions.
11. An Ames mutagenicity assay negative with and without
activation, an in vitro chromosomal aberration using CHO cells positive
with and without activation, an unscheduled DNA synthesis in rat
hepatocytes unequivocally positive in one in vitro assay and negative
in another in vitro assay. A Dominant Lethal Study to further evaluate
the mutagenic mechanism is due March 5, 1995 (2 years after the date of
the initial conditional registration of dimethenamid under the Federal
Insecticide Fungicide and Rodenticide Act [FIFRA]).
The Agency has concluded that the available data provide limited
evidence of carcinogenicity for dimethenamid in rats and has classified
the pesticide as a Category C carcinogen (possible human carcinogen
with limited evidence of carcinogenicity in animals) in accordance with
Agency guidelines, published in the Federal Register in 1986 (51 FR
33992). Based on a review by the Health Effects Division Peer Review
Committee for Carcinogenicity of the Office of Pesticide Programs, the
Agency has determined that a quantitative risk assessment is not
appropriate for the following reasons:
1. The tumor response was primarily due to a significantly
increasing trend for benign and/or malignant liver tumors in males and
due to a significantly increasing trend for ovarian tubular adenomas in
female rats. A re-evaluation of the ovarian neoplasia data indicated
that there was not a statistically significant, dose-related, trend in
the incidence of ovarian tumors in female rats.
2. The chemical was not carcinogenic when administered in the diet
to mice at dose levels ranging from 30 to 3,000 ppm.
Based on this evidence, EPA concludes that dimethenamid poses at
most a negligible cancer risk to humans and that for purposes of risk
characterization the Reference Dose (RfD) approach should be used for
quantification of human risk. Residues of dimethenamid will not
concentrate in processed soybean commodities and a food or feed
additive regulation is not required for dimethenamid.
The standard risk assessment approach of using the RfD based on
systemic toxicity was applied to dimethenamid. Using a hundredfold
safety factor and the NOEL of 5 mg/kg bwt/day determined by the most
sensitive species from the 2-year rat feeding study, the RfD is 0.05
mg/kg/day. The Anticipated Residue Contribution (ARC) from the
established tolerances is 0.000003 mg/kg bwt/day and utilizes 0.007
percent of the RfD for the overall U. S. population. The proposed use
on soybeans would contribute an additional 0.000068 mg/kg/day, raising
the ARC to 0.000071 mg/kg bwt/day, or 0.14 percent of the RfD. The
exposure of the most highly exposed subgroup in the population did not
utilize a significantly greater amount of the RfD.
Tolerances have been previously established for dimethenamid in
corn grain, corn fodder and corn forage. The metabolism of dimethenamid
in plants is adequately understood. There is no reasonable expectation
of secondary residues occurring in meat, milk and eggs from the
tolerance associated with this petition.
An adequate analytical method, gas chromatography, is available for
enforcement purposes. Because of the long lead time from establishing
these tolerances to publication of the enforcement methodology in the
Pesticide Analytical Manual, Vol. II, the analytical methodology is
being made available in the interim to anyone interested in pesticide
enforcement when requested from: Calvin Furlow, Public Information
Branch, Field Operations Division (7506C), Office of Pesticide
Programs, Environmental Protection Agency, 401 M St., SW., Washington,
DC 20460. Office location and telephone number: Room 1130A, CM #2, 1921
Jefferson Davis Highway, Arlington, VA 22202, (703-305-5937).
The pesticide is considered useful for the purposes for which the
tolerances are sought. Based on the information and data considered,
the Agency concludes that the establishment of the tolerances will
protect the public health. Therefore, the tolerances are established as
set forth below.
Any person adversely affected by this regulation may, within 30
days after publication of this document in the Federal Register, file
written objections and/or request a hearing with the Hearing Clerk, 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 objections submitted must
specify the provisions of the regulation deemed objectionable and the
grounds for the objections (40 CFR 178.25). Each objection must be
accompanied by the fees provided by 40 CFR 180.33(i). If a hearing is
requested, the objections must include a statement of the factual
issue(s) on which a hearing is requested, and the requestor's
contentions on each such issue, and a summary of the evidence relied
upon by the objection (40 CFR 178.27). A request for a hearing will be
granted if the Administrator determines that 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 claims 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).
The Office of Management and Budget has exempted this rule from the
requirements of section 2 of Executive Order 12866.
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 of
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: March 28, 1994.
Douglas D. Campt,
Director, Office of Pesticide Programs.
Therefore, chapter I of title 40 of the Code of Federal Regulations
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. Section 180.464 is amended by revising the section heading to
read as set forth below and by alphabetically inserting in the table
the raw agricultural commodity, soybeans, to read as follows:
Sec. 180.464 Dimethenamid, 2-chloro-N-[(1-methyl-2methoxy)ethyl]-N-
(2,4-dimethyl-thien-3-yl)-acetamide; tolerances for residues.
* * * * *
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Commodities Parts per million
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Soybeans........................... 0.01
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[FR Doc. 94-8104 Filed 4-5-94; 8:45 am]
BILLING CODE 6560-50-F
