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Diflubenzuron (Solvay Duphar). May 10, 1995. Pesticide Tolerances. Final Rule. Federal Register.
http://www.epa.gov/docs/fedrgstr/EPA-PEST/1995/May/Day-10/pr-256.html
[Federal Register: May 10, 1995]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[PP 1F2507/R2135; FRL-4954-2]
RIN 2070-AB78
Diflubenzuron; Pesticide Tolerances
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
SUMMARY: This rule establishes tolerances for residues of the insecticide diflubenzuron in or on the raw agricultural commodities orange, grapefruit, and tangerine. Thompson-Hayward Chemical Co. requested pursuant to the Federal Food, Drug and Cosmetic Act (FFDCA) this regulation to establish maximum permissible levels for residues of diflubenzuron in or on the commodities.
EFFECTIVE DATE: May 10, 1995.
ADDRESSES: Written objections, identified by the document control number, [PP 1F2507/R2135], may be submitted to: Hearing Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M St., SW., Washington, DC 20460. 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. A copy of any 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 St., SW., Rm. 1132, CM #2, 1921 Jefferson Davis Hwy., Arlington, VA 22202. A copy of objections and hearing requests filed with the Hearing Clerk may also be submitted electronically by sending electronic mail (e-mail) to: opp-docket@epamail.epa.gov. Copies of objections and hearing requests must be submitted as an ASCII file avoiding the use of special characters and any form of encryption. Copies of objections and hearing requests will also be accepted on disks in WordPerfect in 5.1 file format or ASCII file format. All copies of objections and hearing requests in electronic form must be identified by the docket number [PP 1F2507/R2135]. No Confidential Business Information (CBI) should be submitted through e-mail. Electronic copies of objections and hearing requests on this rule may be filed online at many Federal Depository Libraries. Additional information on electronic submissions can be found below in this document.
FOR FURTHER INFORMATION CONTACT: By mail: Dennis H. Edwards, Jr., Registration Division (7505C), Environmental Protection Agency, 401 M St., SW., Washington, DC 20460. Office location and telephone number: Rm. 207, 1921 Jefferson Davis Hwy., Arlington, VA 22202, (703)-305- 6386; e-mail: edwards.dennis@epamail.epa.gov.
SUPPLEMENTARY INFORMATION: EPA issued a public notice, published in the Federal Register of June 22, 1981 (46 FR 32313), which announced that Thompson-Hayward Chemical Co., P.O. Box 2383, Kansas City, KS 66110, had submitted petitions to EPA proposing tolerances under section 408 of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a, for residues of the insecticide diflubenzuron (N-[[(4- chlorophenyl)amino] carbonyl]-2,6-difluorobenzamide) in or on the raw agricultural commodities orange, grapefruit, and tangerine at 0.50 part per million (ppm) and meat, milk, and eggs [[Page 24786]] at 0.05 ppm. Thompson-Hayward Chemical Co. (P.O. Box 2383, Kansas City, KS 66110) assigned all data rights and obligations connected to diflubenzuron (DFB) to Duphar B. V. of Amsterdam, Holland. Since then, Duphar B.V. has merged with Solvay and is now known as Solvay Duphar. The petitions were subsequently amended, withdrawing the proposed tolerances for animal tissue, milk, and eggs since they were already established. The petitions were amended a second time to include citrus molasses at 0.05 ppm and processed citrus products at 0.05 ppm. (50 FR 32313, August 14, 1985). It was determined that separate tolerances were not needed for processed citrus products since residues in these products were lower than in the raw agricultural product. However, the petition was amended to propose establishment of tolerances for diflubenzuron in citrus oil at 75 ppm and in dried citrus pulp at 1 ppm (52 FR 2969, Jan. 29, 1987).
Notice of the tolerances currently requested by the petitions were republished
on October 1, 1993 (58 FR 54357). There were no comments received in response
to any of the notices of filing. The data submitted in the petition and other
relevant material have been evaluated. The toxicity data considered in support
of the tolerances include an acute oral toxicity study in rats with a median
lethal dose (LD<INF>50) greater than 5,000 milligrams/kilogram body weight
(mg/kg), a 13-week subchronic feeding study in rats with a noobserved -effect-level
(NOEL) of about 2 mg/kg/day (calculated by regression analysis), a 13-week subchronic
feeding study in dogs with a NOEL of 40 ppm in the feed (1.6 mg/kg/day), a 2-year
chronic feeding study in rats with a NOEL of 40 ppm in the feed (1.4 mg/kg/day),
and a 1-year chronic oral (gavage) study in dogs with a NOEL of 2.0 mg/kg/ day.
In all the subchronic and chronic studies listed above, methemoglobinemia and/or
sulfhemoglobinemia were observed at the next higher dose level.
In a 2-year carcinogenicity study in rats at dose levels up to 10,000 ppm in
the feed (500 mg/kg/day) and in a 91-week carcinogenicity study in mice at dose
levels up to 10,000 ppm in the feed (1,500 mg/kg/ day), increased incidences
of tumors were not observed. In developmental toxicity studies in rats and rabbits,
the NOEL for maternal toxicity and for developmental toxicity were greater than
1,000 mg/kg/day, the highest dose tested (HDT). In a two-generation reproduction
study in rats, the NOEL for reproductive performance in adult rats was 50,000
ppm in the feed (2,500 mg/kg/day). Pup weights at this dose level were slightly
reduced from birth to 21 days in F1 offspring.
A battery of genotoxicity studies using diflubenzuron as the test material were
negative. These studies included a Salmonella/mammalian microsome plate incorporation
assay with and without metabolic activation, an in vitro chromosome damage assay
using cultures of Chinese hamster ovary cells with and without metabolic activation,
and an unscheduled DNA synthesis assay using cultures of primary rat hepatocytes.
A metabolism study, using radiolabeled diflubenzuron, is also available.
The reference dose (RfD) for diflbenzuron is 0.02 mg/kg/day and is based on
the NOEL of 2.0 mg/kg/day in the 1-year chronic oral study in dogs. An uncertainty
factor (UF) of 100 was used to calculate the RfD. Granting the tolerance on
orange, grapefruit, and tangerine will increase the theoretical maximum residue
contribution (TMRC) for diflubenzuron from 0.000719 mg/kg/day to 0.001900 mg/kg/day.
The percentage of the RfD used is increased from 4.0 percent to approximately
10 percent. The highest DRES Population Sub-Group ``NonNursing Infants'' shows
an increase from 0.003538 mg/kg/day to 0.006053 mg/kg/day, approximately 31
percent of the RfD. Para-chloroaniline (PCA) and 4-clorophenylurea (CPU) are
metabolites of diflubenzuron that have been observed in studies in lactating
goats, lactating cows, pigs, poultry, rats, and mushrooms. A citrus metabolism
study at the proposed label rate, however, has shown that PCA and CPU were not
detected in whole citrus fruit or in citrus oil at levels above 1 ppb and 2
ppb, respectively. Further, PCA and CPU have not been detected in soybean or
cotton seed. This suggests that diflubenzuron applied to citrus plants, soybeans,
or cotton is not metabolized to PCA or CPU.
PCA has been tested for carcinogenicity by the National Toxicology Program (NTP)
study [Technical Report Series No. 351, NIH Publication No. 89-2806, July 1989].
This test included two year oral studies in F344/N rats and B6C3F1 mice. PCA
was administered by gavage to rats at 0,2,6, or 18 mg/kg/day and to mice at
doses of 0,3,10, or 30 mg/kg/day. A treatment-related increased
incidence of uncommon sarcomas (fibrosarcomas, hemangiosarcomas and osteosarcomas)
of the spleen was observed in the male rats, and an increased incidence of combined
hepatocellular adenomas/carcinomas was observed in male mice in these studies.
The increase in combined tumors in male mice was primarily due to a dose-related
increase in hepatocellular carcinomas. Although diflubenzuron per se is negative
in cancer bioassays, a quantitative cancer risk assessment was performed in
connection with this tolerance because of the finding of small amounts of PCA
and CPU in animals administered large amounts of DFB. Possible human exposure
to PCA and CPU may result from ingestion of PCA and CPU formed in animals consuming
feeds containing diflubenzuron residues and also from metabolic conversion of
diflubenzuron to PCA and CPU in the human body. In doing this risk assessment,
it was assumed that CPU has the same carcinogenic potential and potency as PCA.
Although there is strong evidence supporting the carcinogenicity of PCA in rats
and mice, the assumption that CPU also may be carcinogenic is not based on direct
testing in animals, but rather on a comparison of the chemical structures of
CPU and PCA.
None of the test data examined by the Agency indicated PCA and/or related metabolites
posed a significant carcinogenic risk to humans. EPA estimated a carcinogenic
risk of 2.7 X 10<SUP>-7 from PCA and related metabolites in animal products,
and 1.0 X 10<SUP>-7 from PCA and related products converted in the human
body from diflubenzuron and 9.4 X 10<SUP>-7 from PCA and related metabolites
in mushrooms for a total cancer risk estimate for PCA and related metabolites
of 1.3 X 10<SUP>-6. This estimate was increased significantly by EPA's
assumption that CPU is a carcinogen. EPA concludes that any potential human
cancer risk from this use on citrus and other established uses of diflubenzuron
is negligible.
Solvay Duphar also petitioned for tolerances under FFDCA section 409
for diflubenzuron on citrus pulp and citrus oil. Tolerances are needed to prevent
processed foods from being deemed adulterated when the processed food when ready
to eat contains a pesticide residue at a level greater than permitted by the
corresponding section 408 tolerance. 21 U.S.C. 342(a)(2). EPA has determined,
however, that the citrus pulp and oil tolerances are not necessary. In 1981
and 1986, EPA had concluded that a citrus pulp tolerance was needed due to one
processing study that showed levels of diflubenzuron in citrus pulp 1.9 times
the level in oranges (i.e., a concentration factor of 1.9X). Other processing
studies showed that processing citrus to pulp resulted in a reduction of diflubenzuron
residues or a lower concentration factor than 1.9X. [[Page 24787]] Recently,
EPA has begun averaging results from processing studies in determining concentration
factors and, hence, whether section 409 tolerances are needed. When the results
from all processing studies for citrus pulp are averaged, the concentration
factor is lowered to 1.1X. Given the variability in analytical methods and this
low concentration factor, EPA believes that it is unlikely that any citrus pulp
derived from citrus containing legal levels of diflubenzuron could be reliably
determined to have levels of diflubenzuron above the citrus tolerance. Because
it is unlikely that citrus pulp will have levels of diflubenzuron above the
section 408 tolerance, no section 409 tolerance is needed. EPA has determined
that no section 409 tolerance is necessary for citrus oil because citrus oil
is not a ``ready to eat'' processed food and ``ready to eat'' foods containing
citrus oil are unlikely to have diflubenzuron residues greater than the citrus
tolerance. As noted above, under FFDCA section 402(a)(2), processed foods containing
pesticide residues are not deemed adulterated if the level of pesticide residues
in the processed food ``when ready to eat is not greater than the tolerance
prescribed for the raw agricultural commodity.'' Traditionally, EPA has treated
all processed food as ``ready to eat.'' In a petition filed by the National
Food Processors Association and others, it has been argued that EPA's past practice
is not consistent with the statute. Although EPA will address this issue more
fully in its formal response to that petition, EPA agrees that its approach
to the term ``ready to eat'' has not always been in accord with the plain meaning
of that term. EPA believes that the common sense meaning of the term ``ready
to eat'' food is food ready for consumption without further preparation. Citrus
oil is not consumed ``as is'' but is used as a flavoring in other foods. As
such, citrus oil is not ``ready to eat.'' Further, the use of citrus oil in
the preparation of ``ready to eat'' foods involves such a significant dilution
of the citrus oil that EPA believes that it is unlikely that these foods would
contain levels of diflubenzuron greater than the citrus tolerance. Thus, no
section 409 tolerance is needed for citrus oil. The established tolerance of
0.05 ppm for residues of diflubenzuron on/in eggs, milk, fat, meat, and meat
byproducts of goats, hogs, horses, sheep, and poultry is adequate to cover secondary
residues resulting from the proposed use as delineated in 40 CFR 180.6(a)(2).
The metabolism of diflubenzuron for this use on orange, grapefruit, and tangerine
is adequately understood. The residue of concern is diflubenzuron per se. An
adequate analytical method, gas chromatography with electron capture detector,
is available for enforcement purposes in the Pesticide Analytical Manual, Vol.
II. The pesticide is considered useful for the purpose for which the tolerances
are sought. Based on the information and data considered, the Agency concludes
that the establishment of the tolerances for orange, grapefruit, and tangerine
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 with the Hearing Clerk, at the address given above. 40 CFR 178.20.
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 fee prescribed 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, the requestor's contentions on each such issue,
and a summary of any evidence relied upon by the objector. 40 CFR 178.27. A
request for a hearing will be granted if the Administrator determines that the
material submitted show 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.
A record has been established for this rulemaking under docket number [PP 1F2507/R2135]
(including objections and hearing requests 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 4:30 p.m., Monday through Friday,
excluding legal holidays. The public record is located in Room 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. Written objections and hearing requests,
identified by the document control number [PP 1F2507/R2135], may be submitted
to the Hearing Clerk (1900), Environmental Protection Agency, Rm. 3708, 401
M St., SW., Washington, DC 20460.
A copy of electronic objections and hearing requests filed with the Hearing
Clerk can be sent directly to EPA at: opp-Docket@epamail.epa.gov
A copy of electronic objections and hearing requests filed with the Hearing
Clerk 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 any objections and hearing requests 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 objections and
hearing requests 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 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, 5U.S.C. 601-612), the Administrator has determined that regulations
establishing new tolerances [[Page 24788]] 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).
The Office of Management and Budget has exempted this rule from the requirements
of Section 3 of Executive Order 12866. Pursuant to the requirements of the Regulatory
Flexibility Act (Pub. L. 96-534, 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). (Sec. 408(d)(2), 68 Stat. 512 (21 U.S.C. 346a(d)(2)).)
List of Subjects in 40 CFR Part 180
Environmental protection, Administrative practice and procedure, Agricultural commodities, Pesticides and pests, Reporting and recordkeeping requirements.
Dated: May 5, 1995.
Stephen L. Johnson,
Director, Registration Division, Office of Pesticide Programs.
Therefore, 40 CFR part 180 is amended as follows:
2. Section 180.377 is amended in paragraph (a) in the table therein by adding and alphabetically inserting entries for the commodities orange, grapefruit, and tangerine, to read as follows:
Sec. 180.377 Diflubenzuron; tolerances for residues.
(a) * * *
Parts per
Commodity million
[FR Doc. 95-11495 Filed 5-5-95; 2:12 pm] BILLING CODE 6560-50-F