[Federal Register Volume 60, Number 90 (Wednesday, May 10, 1995)]
[Rules and Regulations]
[Pages 24785-24788]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-11495]



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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.

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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: [email protected]. 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: [email protected].

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 (LD50) greater than 5,000 milligrams/kilogram body 
weight (mg/kg), a 13-week subchronic feeding study in rats with a no-
observed-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 ``Non-
Nursing 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 10-7 from PCA and 
related metabolites in animal products, and 1.0 X 10-7 from PCA 
and related products converted in the human body from diflubenzuron and 
9.4 X 10-7 from PCA and related metabolites in mushrooms for a 
total cancer risk estimate for PCA and related metabolites of 1.3 X 
10-6. 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-D[email protected]


    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:

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

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

    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) *  *  *

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                                                              Parts per 
                         Commodity                             million  
------------------------------------------------------------------------
                                                                        
                  *        *        *        *        *                 
Grapefruit.................................................          0.5
                                                                        
                  *        *        *        *        *                 
Orange.....................................................          0.5
                                                                        
                  *        *        *        *        *                 
Tangerine..................................................          0.5
                                                                        
                  *        *        *        *        *                 
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[FR Doc. 95-11495 Filed 5-5-95; 2:12 pm]
BILLING CODE 6560-50-F