Imidacloprid - Proposed Pesticide Tolerance on Hops 6/95
[Federal Register: July 5, 1995 (Volume 60, Number 128)]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[PP 5E4425/P619; FRL-4962-5]
Imidacloprid; Pesticide Tolerance
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
SUMMARY: EPA proposes to establish a tolerance for residues of the
imidazolidinimine (referred to in this document as imidacloprid) and
its metabolites in or on the raw agricultural commodity dried hops. The
Interregional Research Project No. 4 (IR-4) requested pursuant to the
Federal Food, Drug and Cosmetic Act (FFDCA) the proposed regulation to
establish a maximum permissible level for residues of the insecticide.
DATES: Comments identified by the document control number, [PP 5E4425/
P619], must be received on or before August 4, 1995..
ADDRESSES: By mail, submit written comments 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 comments to: Rm. 1132, CM #2,
1921 Jefferson Davis Highway, Arlington, VA 22202. 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 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 a.m. to 4:30 p.m., Monday through Friday, excluding legal
Comments and data may also be submitted electronically by sending
electronic mail (e-mail) to: firstname.lastname@example.org. 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 [PP 5E4425/P619]. Electronic comments on this proposed
rule may be filed online at many Federal Depository Libraries.
Additional information on electronic submissions can be found in the
"SUPPLEMENTARY INFORMATION" section of this document.
FOR FURTHER INFORMATION CONTACT: By mail: Hoyt L. Jamerson,
Registration Division (7505W), Office of Pesticide Programs,
Environmental Protection Agency, 401 M St. SW., Washington, DC 20460.
Office location and telephone number: Sixth Floor, Crystal Station #1,
2800 Jefferson Davis Highway, Arlington, VA 22202, (703)-308-8783; e-mail:
SUPPLEMENTARY INFORMATION: The Interregional Research Project No. 4
(IR-4), New Jersey Agricultural Experiment Station, P.O. Box 231,
Rutgers University, New Brunswick, NJ 08903, has submitted pesticide
petition (PP) 5E4425 to EPA on behalf of the Agricultural Experiment
Stations of Oregon and Washington. This petition requests that the
Administrator, pursuant to section 408(e) of the Federal Food, Drug,
and Cosmetic Act (FFDCA), 21 U.S.C. 346a(e), amend 40 CFR 180.472 by
establishing a tolerance for residues of the insecticide imidacloprid
(1-[(6-chloro-3-pyridinyl)methyl]-N-nitro-2-imidazolidinimine) and its
metabolites containing the 6-chloropyridinyl moiety, all expressed as
1-[(6-chloro-3-pyridinyl)-methyl]-N-nitro-2-imidazolidinimine, in or on
the raw agricultural commodity dried hops at 6 parts per million (ppm).
In the Federal Register of June 28, 1994 (59 FR 33204), EPA
established a time-limited tolerance for residues of imidacloprid on
dried hops at 3.0 ppm. The imidacloprid tolerance for dried hops was
established to expire on June 28, 1995, to allow IR-4 sufficient time
to conduct additional residue field trials in support of a permanent
tolerance for this use. Subsequently, IR-4 submitted the data from the
residue field trials and petition 5E4425 in support of a permanent
tolerance, but EPA extended the time-limited tolerance to expire on
June 28, 1996 (60 FR 24784, May 10, 1995), when it became apparent that
the IR-4 proposed tolerance could not be established prior to the June
28, 1995 expiration date. The IR-4 residue data have been reviewed and
determined to be adequate to support a permanent tolerance for
imidacloprid on dried hops at 6 ppm.
The toxicological data considered in support of the proposed
1. A 1-year chronic feeding study in dogs fed diets containing 0,
200, 500, or 1,250/2,500 ppm (average intake was 0, 6.1, 15, or 41/72
milligrams (mg)/kilogram (kg)/day) with a noobserved-effect level of
1,250 ppm based on increased plasma cholesterol and liver cytochrome P-
450 levels in dogs at the 2,500-ppm dose level. The high dose was
increased to 2,500 ppm (72 mg/kg/day) from week 17 onward due to lack
of toxicity at the 1,250-dose level.
2. A 2-year feeding/carcinogenicity study in rats fed diets
containing 0, 100, 300, 900, or 1,800 ppm with a NOEL for chronic
effects at 100 ppm (5.7 mg/kg/day in males, 7.6 mg/kg/day in females)
that included decreased body weight gain in females at 300 ppm (24.9
mg/kg/day) and above; and increased thyroid
lesions in males at 300 ppm (16.9 mg/kg/day) and above, and in females
at 900 ppm (73 mg/kg/day) and above. There were no apparent
carcinogenic effects under the conditions of the study.
3. A 2-year carcinogenicity study in mice fed diets containing 0,
100, 330, 1,000, or 2,000 ppm with a NOEL of 1,000 ppm (208 mg/kg/day
in males, 274 mg/kg/day in females) based on decreased food consumption
and decreased water intake at the 2,000-ppm dose level. There were no
apparent carcinogenic effects observed under the conditions of this
4. A three-generation reproduction study with rats feed diets
containing 0, 100, 250, or 700 ppm with a reproductive no-observed-
effect level (NOEL) of 100 ppm (equivalent to 8 mg/kg/day based on
decreased pup body weight observed at the 250-ppm dose level.
5. A developmental toxicity study in rat given gavage doses at 0,
10, 30, or 100 mg/kg/day during gestation days 6 to 16 with a NOEL for
developmental toxicity at 30 mg/kg/day based on increased wavy ribs
observed at the 100 mg/kg/day dose level.
6. A developmental toxicity study in rabbits given gavage doses at
0, 8, 24, or 72 mg/kg/day during gestation days 6 through 19 with a
NOEL for developmental toxicity at 24 mg/kg/day based on decreased body
weight and increased skeletal abnormalities observed at the 72 mg/kg/
day dose level.
7. Imidacloprid, which was tested in a battery of 23 mutagenic
assays, was negative for mutagenic effects in all but two of the
assays. Imidacloprid tested positive for chromosome aberrations in an
in vitro cytogenetic study with human lymphocytes for the detection of
induced clastogenic effects, and for genotoxicity in an in vitro
cytogenetic assay measuring sister chromatid exchange in Chinese
hamster ovary cells.
Dietary risk assessments for imidacloprid indicate that there is
minimal risk from established tolerances and the proposed tolerance for
dried hops. A cancer risk assessment is not appropriate for
imidacloprid since the pesticide is assigned to "Group E" (evidence
of noncarcinogenicity for humans) of EPA's cancer classification
system. Dietary risk assessments for the pesticide were conducted using
the Reference Dose (RfD) to assess chronic exposure and risk and the
Margin of Exposure (MOE) for acute toxicity.
The RfD is calculated at 0.057 mg/kg/of body weight/day based on a
NOEL of 5.7 mg/kg/day from the 2-year rat feeding/carcinogenicity study
and 100-fold uncertainty factor. The theoretical maximum residue
contribution (TMRC) from existing tolerances and the proposed tolerance
for dried hops utilizes less than 5 percent of the RfD for the general
population and 26 percent of the RfD for nonnursing infants less than
one year in age.
The MOE is a measure of how closely the high end acute dietary
exposure comes to the no-observed-effect level from the toxicity
endpoint of concern. For imidacloprid the MOE was calculated as a ratio
of the NOEL (24 mg/kg/day) from the rabbit developmental toxicity study
to dietary exposure, as estimated for the population subgroup at
greatest risk (females of childbearing age). The MOE for this subgroup
is estimated at 2500 for high-end exposure. Acute dietary margins of
exposure of less than 100 are generally of concern to EPA. A MOE of
2,500 poses minimal risk.
Established tolerances for meat, milk, poultry, and eggs are
adequate to cover secondary residues resulting from the feeding of
spent hops to livestock.
The metabolism of imidacloprid in plants and animals is adequately
understood. An adequate analytical method is available for enforcement
purposes. The enforcement method has been submitted to the Food and
Drug Administration for publication in the Pesticide Analytical Manual,
Volume II (PAM II). Because of the long lead time for publication of
the method in PAM II, the analytical method is being made available in
the interim to any one interest in pesticide enforcement when requested
from: Calvin Furlow, Public Response and Program Resources Branch,
Field Operations Divisions (7506C), Office of Pesticide Programs,
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460.
Office location and telephone number: Rm. 1130A, CM #2, 1921 Jefferson
Davis Hwy., Arlington, VA 22202, (703)-305-5937.
There are currently no actions pending against the continued
registration of this chemical.
Based on the information and data considered, the Agency has
determined that the tolerance established by amending 40 CFR part 180
would protect the public health. Therefore, it is proposed that the
tolerance be established as set forth below.
Any person who has registered or submitted an application for
registration of a pesticide, under the Federal Insecticide, Fungicide,
and Rodenticide Act (FIFRA) as amended, which contains any of the
ingredients listed herein, may request within 30 days after publication
of this notice in the Federal Register that this rulemaking proposal be
referred to an Advisory Committee in accordance with section 408(e) of
A record has been established for this rulemaking under docket
number [PP 5E4425/P619] (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 a.m. to 4 p.m., Monday through Friday, excluding legal holidays.
The public record is located in Rm. 1132 of the Public Response and
Program Resources Branch, Field Operations Division (7506C), Office of
Pesticide Programs, Environmental Protection Agency, Crystal Mall #2,
1921 Jefferson Davis Highway, Arlington, VA.
Electronic comments can be sent directly to EPA at:
Electronic comments must be submitted as an ASCII file avoiding the
use of special characters and any form of encryption.
The official record for this rulemaking, as well as the public
version, as described above will be kept in paper form. Accordingly,
EPA will transfer all comments received electronically into printed,
paper form as they are received and will place the paper copies in the
official rulemaking record which will also include all comments
submitted directly in writing. The official rulemaking record is the
paper record maintained at the address in "ADDRESSES" at the
beginning of this document.
Under Executive Order 12866 (58 FR 51735, Oct. 4, 1993), the Agency
must determine whether the regulatory action is "significant" and
therefore subject to all the requirements of the Executive Order (i.e.,
Regulatory Impact Analysis, review by the Office of Management and
Budget (OMB)). Under section 3(f), the order defines "significant" as
those actions likely to lead to a rule (1) having an annual effect on
the economy of $100 million or more, or adversely and materially
affecting a sector of the economy, productivity, competition, jobs, the
environment, public health or safety, or State, local or tribal
governments or communities (also known as "economically significant"); (2)
creating serious inconsistency or otherwise interfering with an action taken
or planned by another agency; (3) materially altering the budgetary impacts of
entitlement, grants, user fees, or loan programs; or (4) raising novel legal
or policy issues arising out of legal mandates, the President's priorities, or
the principlesset forth in this Executive Order.
Pursuant to the terms of this Executive Order, EPA has determined
that this rule is not "significant" and is therefore not subject to
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
Dated: June 23, 1995.
Acting Director, Registration Division, Office of Pesticide Programs.
Therefore, it is proposed that 40 CFR part 180 be amended as
1. The authority citation for part 180 continues to read as
Authority: 21 U.S.C. 346a and 371.
2. In Sec. 180.472, paragraph (a) is amended in the table therein
by adding and alphabetically inserting dried hops, and paragraph (d) is
removed, as follows:
Sec. 180.472 1-[(6-Chloro-3-pyridinyl)methyl]-N-nitro-2-
imidazolidinimine; tolerances for residues.
(a) * * *
* * * * *
Hops, dried................................................ 6
* * * * *
* * * * *