[Federal Register Volume 65, Number 66 (Wednesday, April 5, 2000)]
[Notices]
[Pages 17872-17876]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-8262]


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ENVIRONMENTAL PROTECTION AGENCY

[PF-931; FRL-6550-7]


Notice of Filing a Pesticide Petition to Establish a Tolerance 
for Certain Pesticide Chemicals in or on Food

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: This notice announces the initial filing of a pesticide 
petition proposing the establishment of regulations for residues of 
certain pesticide chemicals in or on various food commodities.

DATES: Comments, identified by docket control number PF-931, must be 
received on or before May 5, 2000.

ADDRESSES: Comments may be submitted by mail, electronically, or in 
person. Please follow the detailed instructions for each method as 
provided in Unit I.C. of the ``SUPPLEMENTARY INFORMATION.'' To ensure 
proper receipt by EPA, it is imperative that you identify docket 
control number PF-931 in the subject line on the first page of your 
response.

FOR FURTHER INFORMATION CONTACT:  By mail: Shaja R. Brothers, 
Registration Division (7505C), Office of Pesticide Programs, 
Environmental Protection Agency, Ariel Rios Bldg., 1200 Pennsylvania 
Ave., NW., Washington, DC 20460; telephone number: (703) 308-3194; e-
mail address: [email protected].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be affected by this action if you are an agricultural 
producer, food manufacturer or pesticide manufacturer. Potentially 
affected categories and entities may include, but are not limited to:

 
------------------------------------------------------------------------
                                                          Examples of
           Categories                NAICS  codes         potentially
                                                       affected entities
------------------------------------------------------------------------
Industry                          111                 Crop production
                                  112                 Animal production
                                  311                 Food manufacturing
                                  32532               Pesticide
                                                       manufacturing
------------------------------------------------------------------------

    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in the table could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether or not this action might apply to certain entities. If you have 
questions regarding the applicability of this action to a particular 
entity, consult the person listed under ``FOR FURTHER INFORMATION 
CONTACT.''

B. How Can I Get Additional Information, Including Copies of this 
Document and Other Related Documents?

    1. Electronically. You may obtain electronic copies of this 
document, and certain other related documents that might be available 
electronically, from the EPA Internet Home Page at http://www.epa.gov/. 
To access this document, on the Home Page select ``Laws and 
Regulations'' and then look up the entry for this document under the 
``Federal Register--Environmental Documents.'' You can also go directly 
to the Federal Register listings at http://www.epa.gov/fedrgstr/.

[[Page 17873]]

    2. In person. The Agency has established an official record for 
this action under docket control number PF-931. The official record 
consists of the documents specifically referenced in this action, any 
public comments received during an applicable comment period, and other 
information related to this action, including any information claimed 
as confidential business information (CBI). This official record 
includes the documents that are physically located in the docket, as 
well as the documents that are referenced in those documents. The 
public version of the official record does not include any information 
claimed as CBI. The public version of the official record, which 
includes printed, paper versions of any electronic comments submitted 
during an applicable comment period, is available for inspection in the 
Public Information and Records Integrity Branch (PIRIB), Rm. 119, 
Crystal Mall #2, 1921 Jefferson Davis Highway, Arlington, VA, from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.

C. How and to Whom Do I Submit Comments?

    You may submit comments through the mail, in person, or 
electronically. To ensure proper receipt by EPA, it is imperative that 
you identify docket control number PF-931 in the subject line on the 
first page of your response.
    1. By mail. Submit your comments to: Public Information and Records 
Integrity Branch (PIRIB), Information Resources and Services Division 
(7502C), Office of Pesticide Programs (OPP), Environmental Protection 
Agency, Ariel Rios Bldg., 1200 Pennsylvania Ave., NW., Washington, DC 
20460.
    2. In person or by courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Information Resources 
and Services Division (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, Rm. 119, Crystal Mall #2, 1921 
Jefferson Davis Highway, Arlington, VA. The PIRIB is open from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.
    3. Electronically. You may submit your comments electronically by 
e-mail to: ``[email protected],'' or you can submit a computer disk as 
described above. Do not submit any information electronically that you 
consider to be CBI. Avoid the use of special characters and any form of 
encryption. Electronic submissions will be accepted in Wordperfect 6.1/
8.0 or ASCII file format. All comments in electronic form must be 
identified by docket control number PF-931. Electronic comments may 
also be filed online at many Federal Depository Libraries.

D. How Should I Handle CBI That I Want to Submit to the Agency?

    Do not submit any information electronically that you consider to 
be CBI. You may claim information that you submit to EPA in response to 
this document as CBI by marking any part or all of that information as 
CBI. Information so marked will not be disclosed except in accordance 
with procedures set forth in 40 CFR part 2. In addition to one complete 
version of the comment that includes any information claimed as CBI, a 
copy of the comment that does not contain the information claimed as 
CBI must be submitted for inclusion in the public version of the 
official record. Information not marked confidential will be included 
in the public version of the official record without prior notice. If 
you have any questions about CBI or the procedures for claiming CBI, 
please consult the person identified under ``FOR FURTHER INFORMATION 
CONTACT.''

E. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide copies of any technical information and/or data you used 
that support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at the estimate that you provide.
    5. Provide specific examples to illustrate your concerns.
    6. Make sure to submit your comments by the deadline in this 
notice.
    7. To ensure proper receipt by EPA, be sure to identify the docket 
control number assigned to this action in the subject line on the first 
page of your response. You may also provide the name, date, and Federal 
Register citation.

II. What Action is the Agency Taking?

    EPA has received a pesticide petition as follows proposing the 
establishment and/or amendment of regulations for residues of certain 
pesticide chemical in or on various food commodities under section 408 
of the Federal Food, Drug, and Comestic Act (FFDCA), 21 U.S.C. 346a. 
EPA has determined that this petition contains data or information 
regarding the elements set forth in section 408(d)(2); however, EPA has 
not fully evaluated the sufficiency of the submitted data at this time 
or whether the data supports granting of the petition. Additional data 
may be needed before EPA rules on the petition.

List of Subjects

    Environmental protection, Agricultural commodities, Feed additives, 
Food additives, Pesticides and pests, Reporting and recordkeeping 
requirements.

    Dated: March 28, 2000
James Jones
Director, Registration Division, Office of Pesticide Programs.

Summary of Petition

    The petitioner summary of the pesticide petition is printed below 
as required by section 408(d)(3) of the FFDCA. The summary of the 
petition was prepared by the petitioner and represents the view of the 
petitioners. EPA is publishing the petition summary verbatim without 
editing it in any way. The petition summary announces the availability 
of a description of the analytical methods available to EPA for the 
detection and measurement of the pesticide chemical residues or an 
explanation of why no such method is needed.

Interregional Research Project Number 4

5E4499

    EPA has received a pesticide petition (5E4499) from Rutgers, the 
State University of New Jersey, 681 U.S. Highway No. 1 South, New 
Brunswick, NJ 08902 proposing, pursuant to section 408(d) of the 
Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a(d), to 
amend 40 CFR part 180 by establishing a tolerance for residues of 
diflubenzuron in or on the raw agricultural commodity rangeland grass 
at 6.0 parts per million (ppm). EPA has determined that the petition 
contains data or information regarding the elements set forth in 
section 408(d)(2) of the FFDCA; however, EPA has not fully evaluated 
the sufficiency of the submitted data at this time or whether the data 
support granting of the petition. Additional data may be needed before 
EPA rules on the petition. This notice includes a summary of the 
petition prepared by Uniroyal Chemical Company, 74 Amity Road, Bethany, 
CT 06525.

[[Page 17874]]

A. Residue Chemistry

    1. Plant metabolism. The qualitative nature of the residue in 
plants is adequately understood based on data from soybeans, oranges, 
and rice metabolism studies.
    2. Analytical method. A practical analytical method for detecting 
and measuring levels of diflubenzuron in or on food with a limit of 
detection that allows monitoring of the residue at or above the level 
set in the tolerance was used to determine residues in rangeland grass. 
Rangeland grass samples are analyzed by high performance liquid 
chromotography and detected by UV-absorption at 254 nanometers liquid 
chromatography for quantitation of diflubenzuron residues at a limit of 
quantitation (LOQ) for the method on rangeland grass of 0.05 ppm.

B. Toxicological Profile

    1. Acute toxicity. Studies for diflubenzuron technical indicate the 
acute oral toxicity in rats and mice >4,640 milligrams/kilograms (mg/
kg), and the acute dermal toxicity in rats is >10,000 mg/kg. The acute 
inhalation lethal concentration: (LC)50 in rats is >35 mg/L 
(6 hours). Diflubenzuron technical is not an eye or skin irritant to 
rabbits, and is not a dermal sensitizer in guinea pigs.
    2. Genotoxcity. Diflubenzuron did not show any mutagenic activity 
in point mutation assays employing Salmonella typhimurium, S. 
cerevisiae, or L5178Y mouse lymphoma cells. Diflubenzuron did not 
induce chromosomal aberrations in Chinese hamster ovary cells and it 
did not induce unscheduled DNA synthesis in human WI-38 cells. 
Diflubenzuron was also negative in mouse micronucleus and mouse 
dominant lethal assays and it did not induce cell transformation in 
Balb/3T3 cells.
    3. Reproductive and developmental toxicity. In a rat reproduction 
study, diflubenzuron was fed to 2 generations of male and female rats 
at dietary concentrations of 0, 10, 20, 40, and 160 ppm. No effects 
were seen on parental body weight gain and there were no reproductive 
effects. A subsequent study was conducted on 1-generation (one litter) 
of rats at dietary concentrations of 0, 1,000 and 100,000 ppm. Systemic 
effects were seen in adults at these doses but there was no effect on 
reproductive parameters. The no observed adverse effect level (NOAEL) 
for reproductive toxicity was greater than 100,000 ppm (5 mg/kg/day).
    In a rat developmental toxicity study, diflubenzuron was 
administered by oral gavage to pregnant female rats at dosage levels of 
0, 1, 2, and 4 mg/kg/day. No treatment related effects were seen. A 
subsequent study was conducted in pregnant Sprague Dawley rats at a 
dose of 0 and 1,000 mg/kg/day. No maternal toxicity was observed. The 
incidence of fetuses with skeletal abnormalities was slightly increased 
in the treated group, but was within historical background range. The 
NOAEL for maternal and developmental toxicity in rats was greater than 
1,000 mg/kg/day.
    Diflubenzuron was also administered by oral gavage to pregnant New 
Zealand white rabbits at dosage levels of 0, 1, 2, and 4 mg/kg/day. No 
treatment related effects were seen. A subsequent study was conducted 
in pregnant rabbits at doses of 0 and 1,000 mg/kg/day. No maternal or 
developmental toxicity was seen. The NOAEL for maternal and 
developmental toxicity in rabbits was greater than 1,000 mg/kg/day.
    4. Subchronic toxicity. A 4-week inhalation study and a 3-week 
dermal study were conducted. In the inhalation study, rats were exposed 
(nose only) to 10, 30, or 100 mg/m3 for 6 hours per day, 5 
days per week for 4 weeks. Treatment related findings were a slight 
reduction in erythrocytes, hemoglobin and hematocrit in male and female 
rats at a concentration of 100 mg/m3 and an increase in 
total bilirubin in high dose female rats. There was no effect on 
methemoglobin concentration at any dose level. The NOAEL for subchronic 
inhalation toxicity was 30 mg/m3.
    5. Chronic toxicity. Diflubenzuron was given by capsule to male and 
female beagle dogs for 1-year at dose levels of 0, 2, 10, 50, and 250 
mg/kg/day. Body weight gain was slightly reduced in females at 250 mg/
kg/day. Absolute liver and spleen weights were increased in males given 
50 and 250 mg/kg/day. A reduction in hemoglobin and mean corpuscular 
hemoglobin concentration, with an elevation in reticulocyte count, was 
seen at 50 and 250 mg/kg/day. Methemoglobin and sulfhemoglobin values 
were increased at doses of 10 mg/kg/day and greater. Histopathological 
findings were limited to pigmented macrophages and kupffer cells in the 
liver at doses of 50 and 250 mg/kg/day. The NOAEL for chronic toxicity 
in dogs was 2 mg/kg/day.
    Diflubenzuron was fed to male and female Sprague Dawley rats for 2 
years at dose levels of 0, 156, 625, 2,500, and 10,000 ppm. 
Methemoglobin values were elevated in female rats at all dose levels 
and in male rats at the two highest dose levels (HDL). Sulfhemoglobin 
was elevated in females, only, at dose levels of 2,500 and 10,000 ppm. 
Mean corpuscular volume (MCV) and reticulocyte counts were increased in 
high dose females. Spleen and liver weights were elevated at the two 
highest doses. Histopathological examination demonstrated an increase 
in hemosiderosis of the liver and spleen, bone marrow and erythroid 
hyperplasia and areas of cellular alteration in the liver. In another 
study, diflubenzuron was administered to male and female CD rats for 2 
years at dose levels of 0, 10, 20, 40, and 160 ppm. Elevated 
methemoglobin levels were seen in high dose males and females. No 
additional effects, including carcinogenic findings, were observed. The 
NOAEL for chronic toxicity in rats was 40 ppm (2 mg/kg/day).
    Carcinogenicity. A 91-week carcinogenicity study in CFLP mice was 
conducted at doses of 0, 16, 80, 400, 2,000, and 10,000 ppm. There was 
no increase in tumor incidence as a result of diflubenzuron 
administration. Target organ effects included: increased methemoglobin 
and sulfhemoglobin values, heinz bodies, increased liver and spleen 
weight, hepatocyte enlargement and vacuolation, extramedullary 
hemopoiesis in the liver and spleen, siderocytosis in the spleen and 
pigmented kupffer cells. A NOAEL for these effects was 16 ppm (2 mg/kg/
day).
    6. Animal metabolism. Diflubenzuron in rats at a single dose of 100 
mg/kg and 5 mg/kg single and mutiple oral doses depicted limited 
absorption from the gastrointestinal tract. No major difference was 
observed between the single and multiple doses. In single dose 
treatments, after 7 days, 20 and 3% of the applied dose 5 and 100 mg/
kg, respectively, were excreted in urine, while 79 and 98% of the 
applied dose 5 and 100 mg/kg, respectively, were eliminated in the 
feces. Very little bioaccumulation in the tissues was observed. In the 
feces, only unchanged parent compound was detected. Several metabolites 
were observed in the urine which are, among others, 2,6-diflurobenzoic 
acid (DFBA), 2,6-difluorophippuric acid, 2,6-difluorobenzamide (DFBAM), 
and 2-hydroxydiflubenzuron (2-HDFB). An unresolved peak that was 
characterized as p-chloroaniline (PCA) and/or p-chlorophenylurea (CPU) 
was found. This latter peak accounted for about 2% of the administered 
dose (5 mg/kg). To resolve if PCA and CPU are indeed metabolites of 
diflubenzuron, rats were administered a single oral dose, 100 mg/kg of 
14C DFB. The major metabolites identified in rat urine were 4-
chloroaniline-2-sulfate, accounting for almost 50% of the total 
radioactive residue (TRR) in the urine and N-(4-chlorophenyl)oxamic 
acid which

[[Page 17875]]

accounted for about 15% of the TRR. Neither CPU, PCA nor their N-
hydroxyl derivatives were found in rat urine at a limit of detection of 
23 ppb. As in the previous study diflubenzuron was the only residue 
found in the feces.
    7. Metabolite toxicology. PCA hydrochloride for male and female 
F344/N rats, and PCA hydrochloride for male B6C3F1 mice under the 
condition of a 2-year gavage study showed evidence of carcinogenic 
activity. In addition to PCA, 4-chlorophenylurea (CPU) is also a 
potential minor metabolite of diflubenzuron.
    8. Endocrine disruption. The standard battery of required studies 
has been completed and evaluated to determine potential estrogenic or 
endocrine effects of diflubenzuron. These studies include an evaluation 
of the potential effects on reproduction and development, and an 
evaluation of the pathology of the endocrine organs following repeated 
or long-term exposure. These studies are generally considered to be 
sufficient to detect any endocrine effects. No such effects were noted 
in any of the studies with diflubenzuron.

C. Aggregate Exposure

    1. Dietary exposure-- i. Food. Since 1-day single dose oral studies 
in rats and mice indicated only marginal effects, an acute exposure 
risk assessment is not needed, as there were no significant acute 
effects observed.
    a. Diflubenzuron. The chronic dietary exposure from diflubenzuron 
was estimated based on the average residue values from the various 
currently labeled raw agricultural commodities. Percent of crop treated 
was also factored into the estimate. The dietary exposure analysis was 
estimated based on 1989-92 USDA food consumption data.
    The U.S. population (total), the dietary exposure of diflubenzuron 
was estimated as 0.000013 mg/kg/day. For nursing and non-nursing 
infants, the exposure was estimated as 0.000003 mg/kg/day and 0.000007 
mg/kg/day, respectively. For children, the exposure was 0.000015 mg/kg/
day and 0.000011 mg/kg/day for 1-6 year olds and 7-12 year olds, 
respectively.
    b. p-Chloroaniline. The chronic dietary exposure from p-
chloroaniline (PCA) which has been detected in some food products was 
also determined. Average residues from field trials for mushrooms and 
rice were used. Residues in liver were obtained from extrapolation of 
metabolism data to anticipated livestock dietary burdens. EPA has 
previously used a 2 percent in vivo conversion factor of DFB to PCA for 
foods derived from plant products. However, based on results of a 
recent rat metabolism study showing that no PCA is formed, this is no 
longer appropriate. The percent treated of each crop was also factored 
into the exposure estimate.
    The U.S. population (total), the dietary exposure of PCA was 
estimated as 0.000001 mg/kg/day. For nursing and non-nursing infants, 
the exposure was estimated as 0.000001 mg/kg/day and 0.000001 mg/kg/
day, respectively. For children 1-6 years old and 7-12 years old, the 
exposure was 0.000001 mg/kg/day.
    ii. Drinking water. Diflubenzuron degrades in soil relatively 
quickly with aerobic half-life ranging from 3-7 days. Major degradates 
include difluorobenzoic acid (DFBA) and CPU. DFBA is further 
metabolized through decarboxylation and ring cleavage by soil microbes 
whereas CPU is slowly degraded to soil-bound entities. Under aerobic 
aquatic conditions, diflubenzuron has a half-life of 34 days with the 
main degradates being DFBA and CPU. In surface water, diflubenzuron is 
degraded by microbes with a half-life of 5-10 days. The soil mobility 
of diflubenzuron is considered quite limited based on a number of 
experimental studies as well as by computer modeling. CPU has also been 
shown to be relatively immobile in soil. Although DFBA shows mobility 
in soil, it is rapidly degraded. Therefore, based on results of 
laboratory and field studies, it is not likely that diflubenzuron or 
its degradates will impact ground water quality to any significant 
extent.
    Based on EPA's PRZM/EXAMS modeling, the average annual mean 
concentration of diflubenzuron in surface water sources is not expected 
to exceed 0.05 ppb. The drinking water level of concern (DWLOC) for 
chronic (non-cancer) exposure to diflubenzuron in drinking water was 
determined as 699 parts per billion (ppb) for the U.S. population 
(total) and approximately 200 ppb for infants and children. The 
estimated maximum concentration of diflubenzuron in surface water (0.05 
ppb) is much less than the DWLOCs as a contribution to chronic (non-
cancer) aggregate exposure.
    2. Non-dietary exposure. Diflubenzuron is a restricted use 
pesticide based on its toxicity to aquatic invertebrates. This 
restricted use classification makes it unavailable for use by 
homeowners. Occupational uses of diflubenzuron may expose people in 
residential locations, parks, or forests treated with diflubenzuron. 
Based on very low residues detected in forestry dissipation studies, 
low dermal absorption rate (0.05%), and extremely low dermal and 
inhalation toxicity, these uses are expected to result in insignificant 
risk, and will, therefore, not be included in the aggregate risk 
assessment.

D. Cumulative Effects

    Uniroyal Chemical Company has considered the potential for 
cumulative effects of diflubenzuron and other substances with a common 
mechanism of toxicity. The mammalian toxicity of diflubenzuron is well 
defined. We are not aware of any other pesticide product registered in 
the U.S. that could be metabolized to p-chloroaniline. For this reason, 
consideration of potential cumulative effects of residues from 
pesticidal substances with a common mechanism of action as 
diflubenzuron is not appropriate. Thus, only the potential exposures to 
diflubenzuron were considered in the total exposure assessment.

E. Safety Determination

    1. U.S. population. Dietary exposure to the U.S. population (total) 
from diflubenzuron was estimated at 0.000013 mg/kg/day. Based on the 
0.02 mg/kg/day RfD (reference dose) derived from the dog chronic NOAEL 
of 2 mg/kg/day and a 100-fold safety factor, this dietary exposure is 
0.1% of the RfD. Since estimated concentrations of diflubenzuron in 
drinking water are well below the drinking water levels of concern, 
aggregate exposure is not expected to exceed 100% of the RfD. 
Therefore, there is a reasonable certainty that no harm will result 
from aggregate exposure to diflubenzuron residues.
    For PCA, dietary exposure to the U.S. population (total) was 
estimated as less than 0.000001 mg/kg/day. The risk from diflubenzuron-
derived PCA can be estimated using a linear extrapolation of the dose-
response from the rat chronic study conducted by the National 
Toxicology Program in which rats were dosed via gavage with p-
chloroaniline [hydrochloride] for 24 months. EPA has determined the q1* 
as 0.0638, based on the combined sarcoma incidence in the spleen of 
male rats. In view of the results of recent CPU rat mechanistic and 
metabolism studies, and the diflubenzuron rat metabolism study, the 
dietary risk assessment included here considers only actual residues of 
PCA found in food and animal by-products. This is consistent with a 
parent compound, such as diflubenzuron, which is negative (Category E) 
for carcinogenicity. It is also consistent with EPA's manner of 
treatment of other active ingredients that are clearly negative for 
carcinogenicity. Using the q1* of 0.0638, the risk to the U.S. 
population (total) from dietary exposure

[[Page 17876]]

to diflubenzuron-derived PCA is 1.31 x 10-8. This risk is 
below EPA's level of concern.
    2. Infants and children. The same assumptions as for the U.S. 
population were used for the dietary exposure risk determination in 
infants and children. The dietary exposure of diflubenzuron was 
calculated as 0.000003 mg/kg/day and 0.000007 mg/kg/day respectively 
for nursing and non-nursing infants. These values are 0.2% and 0.4%, 
respectively of the RfD for diflubenzuron. The dietary exposure from 
diflubenzuron in children 1-6 and 7-12 years old was determined as 
0.000015 mg/kg/day and 0.000011 mg/kg/day, respectively. These values 
are 0.1% of the RfD.
    As previously discussed, the NOAELs for maternal and developmental 
toxicity in rats and rabbits were greater than 1,000 mg/kg/day, and the 
NOAEL for reproductive toxicity was greater than 5,000 mg/kg/day. 
Therefore, based on the completeness and reliability of the toxicity 
data and the conservative exposure assessment, Uniroyal concludes that 
there is reasonable certainty that no harm will result in infants and 
children from aggregate exposure to residues of diflubenzuron and its 
conversion products containing the p-chloroaniline moiety.

F. International Tolerances

    There is no Codex Alimentarius Commission Maximum Residue Level for 
Residues of diflubenzuron on range grass.
[FR Doc. 00-8262 Filed 4-4-00; 8:45 am]
BILLING CODE 6560-50-F