Document ID: EPA-HQ-OPP-2012-0515-0007
Agency: epa
Document Type: Rule
Title: Pesticide Tolerances: Diflubenzuron
Posted Date: 2014-01-31T05:00Z

[Federal Register Volume 79, Number 21 (Friday, January 31, 2014)]
[Rules and Regulations]
[Pages 5294-5300]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-02064]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2012-0515; FRL-9904-27]

Diflubenzuron; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for residues of 
diflubenzuron (N-[[(4-chlorophenyl)amino]carbonyl]-2,6-
difluorobenzimide) in or on fruit, citrus, group 10-10 and citrus, oil. 
Chemtura Corporation, requested these tolerances under the Federal 
Food, Drug, and Cosmetic Act (FFDCA).

DATES: This regulation is effective January 31, 2014. Objections and 
requests for hearings must be received on or before April 1, 2014, and 
must be filed in accordance with the instructions provided in 40 CFR 
part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).

ADDRESSES: The docket for this action, identified by docket 
identification (ID) number EPA-HQ-OPP-2012-0515, is available at http://www.regulations.gov or at the Office of Pesticide Programs Regulatory 
Public Docket (OPP Docket) in the Environmental Protection Agency 
Docket Center (EPA/DC), EPA West Bldg., Rm. 3334, 1301 Constitution 
Ave. NW., Washington, DC 20460-0001. The Public Reading Room is open 
from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal 
holidays. The telephone number for the Public Reading Room is (202) 
566-1744, and the telephone number for the OPP Docket is (703) 305-
5805. Please review the visitor instructions and additional information 
about the docket available at http://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT: Lois Rossi, Registration Division, 
Office of Pesticide Programs, Environmental Protection Agency, 1200 
Pennsylvania Ave. NW., Washington, DC 20460-0001; telephone number: 
(703) 305-7090; email address: RDFRNotices@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this action apply to me?

    You may be potentially affected by this action if you are an 
agricultural producer, food manufacturer, or pesticide manufacturer. 
The following list of North American Industrial Classification System 
(NAICS) codes is not intended to be exhaustive, but rather provides a 
guide to help readers determine whether this document applies to them. 
Potentially affected entities may include:
     Crop production (NAICS code 111).
     Animal production (NAICS code 112).
     Food manufacturing (NAICS code 311).
     Pesticide manufacturing (NAICS code 32532).

B. How can I get electronic access to other related information?

    You may access a frequently updated electronic version of EPA's 
tolerance regulations at 40 CFR part 180 through the Government 
Printing Office's e-CFR site at http://www.ecfr.gov/cgi-bin/text-idx?&c=ecfr&tpl=/ecfrbrowse/Title40/40tab_02.tpl.

C. How can I file an objection or hearing request?

    Under FFDCA section 408(g), 21 U.S.C. 346a, any person may file an 
objection to any aspect of this regulation and may also request a 
hearing on those objections. You must file your objection or request a 
hearing on this regulation in accordance with the instructions provided 
in 40 CFR part 178. To ensure proper receipt by EPA, you must identify 
docket ID number EPA-HQ-OPP-2012-0515 in the subject line on the first 
page of your submission. All objections and requests for a hearing must 
be in writing, and must be received by the Hearing Clerk on or before 
April 1, 2014. Addresses for mail and hand delivery of objections and 
hearing requests are provided in 40 CFR 178.25(b).
    In addition to filing an objection or hearing request with the 
Hearing Clerk as described in 40 CFR part 178, please submit a copy of 
the filing (excluding any Confidential Business Information (CBI)) for 
inclusion in the public docket. Information not marked confidential 
pursuant to 40 CFR part 2 may be disclosed publicly by EPA without 
prior notice. Submit the non-CBI copy of your objection or hearing 
request, identified by docket ID number EPA-HQ-OPP-2012-0515, by one of 
the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the online instructions for submitting comments. Do not submit 
electronically any information you consider to be CBI or other 
information whose disclosure is restricted by statute.
     Mail: OPP Docket, Environmental Protection Agency Docket 
Center (EPA/DC), (28221T), 1200 Pennsylvania Ave. NW., Washington, DC 
20460-0001.
     Hand Delivery: To make special arrangements for hand 
delivery or delivery of boxed information, please follow the 
instructions at http://www.epa.gov/dockets/contacts.html.
Additional instructions on commenting or visiting the docket, along 
with more information about dockets generally, is available at http://www.epa.gov/dockets.

II. Summary of Petitioned-for Tolerance

    In the Federal Register of September 12, 2013 (78 FR 56185) (FRL-
9399-7), EPA issued a document pursuant to FFDCA section 408(d)(3), 21 
U.S.C. 346a(d)(3), announcing the filing of a pesticide petition (PP 
2F8015) by Chemtura Corporation,199 Benson Road, Middlebury, CT 06749. 
The petition requested that 40 CFR 180.377 be amended by establishing 
tolerances for residues of the insecticide diflubenzuron, (DFB) and its 
metabolites 4-chlorophenylurea (CPU) and 4-chloroaniline (PCA), in or 
on fruit, citrus, group 10-10 at 3.0 parts per million (ppm), and 
citrus, oil at 32.0

[[Page 5295]]

ppm. That document referenced a summary of the petition prepared by 
Chemtura Corporation, the registrant, which is available in the docket, 
http://www.regulations.gov. There were no comments received in response 
to the notice of filing.
    In conjunction with this rulemaking, EPA has updated the tolerance 
expression to be consistent with the FFDCA. See Unit IV.D. EPA is also 
removing the existing tolerances for grapefruit, orange, pummelo, and 
tangerine that are made redundant by establishment of the crop group 
tolerance for citrus.

III. Aggregate Risk Assessment and Determination of Safety

    Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a 
tolerance (the legal limit for a pesticide chemical residue in or on a 
food) only if EPA determines that the tolerance is ``safe.'' Section 
408(b)(2)(A)(ii) of FFDCA defines ``safe'' to mean that ``there is a 
reasonable certainty that no harm will result from aggregate exposure 
to the pesticide chemical residue, including all anticipated dietary 
exposures and all other exposures for which there is reliable 
information.'' This includes exposure through drinking water and in 
residential settings, but does not include occupational exposure. 
Section 408(b)(2)(C) of FFDCA requires EPA to give special 
consideration to exposure of infants and children to the pesticide 
chemical residue in establishing a tolerance and to ``ensure that there 
is a reasonable certainty that no harm will result to infants and 
children from aggregate exposure to the pesticide chemical residue. . . 
.''
    Consistent with FFDCA section 408(b)(2)(D), and the factors 
specified in FFDCA section 408(b)(2)(D), EPA has reviewed the available 
scientific data and other relevant information in support of this 
action. EPA has sufficient data to assess the hazards of and to make a 
determination on aggregate exposure for diflubenzuron including 
exposure resulting from the tolerances established by this action. 
EPA's assessment of exposures and risks associated with diflubenzuron 
follows.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its 
validity, completeness, and reliability as well as the relationship of 
the results of the studies to human risk. EPA has also considered 
available information concerning the variability of the sensitivities 
of major identifiable subgroups of consumers, including infants and 
children.
    The acute oral, dermal and inhalation toxicity of diflubenzuron is 
low. It is a mild eye irritant and not a skin irritant in laboratory 
animals. It is negative for sensitization in the guinea pig. In 
subchronic and chronic feeding studies, the primary endpoint of concern 
was methemoglobinemia and/or sulfhemoglobinemia. These effects were 
evident in both sexes of mice, rats, and dogs and were produced by more 
than one route of administration in rats (i.e., oral, dermal and 
inhalation). The general consequence of methemoglobinemia and/or 
sulfhemoglobinemia is the impairment of the oxygen transportation 
capacity of the blood, which is generally known to be caused by 
aromatic amines in both humans and animals. Degradates of diflubenzuron 
with aromatic amines, CPU and PCA, are also included in the 
diflubenzuron non-cancer risk assessment. CPU, an analog of monuron, 
does not effect methemoglobin formation but does produce tumors in the 
liver and kidneys of male rats. The toxicity of PCA is well understood 
with methemoglobin formation the primary systemic effect. PCA is 
similar in potency to diflubenzuron on methemoglobin formation. 
Therefore, the non-cancer assessment will include diflubenzuron, CPU 
and PCA. Since the toxicity of CPU and PCA is well understood, 
additional toxicity studies are not required.
    The toxicity data provide no indication of an increased 
susceptibility to rats or to rabbits from in utero or postnatal 
exposure to diflubenzuron. Developmental and reproduction studies in 
rats and rabbits indicate a very low hazard potential for adverse 
effects. Developmental studies were tested at the limit dose of 1,000 
milligrams/kilogram/day (mg/kg/day) without apparent effects in both 
dams and the fetuses. The reproduction study indicated that effects in 
offspring occurred at doses that were higher than the doses producing 
effects in parents. The requirement for acute and subchronic 
neurotoxicity studies were recently waived because there are no clear 
signs of neurotoxicity following subchronic or chronic dosing in 
multiple species in the diflubenzuron database. The toxicity profile of 
diflubenzuron shows that the principal toxic effects are the formation 
of methemoglobinemia and/or sulfhemoglobinemia in the blood. The 
immunotoxicity study has been reviewed and immunotoxicity was not 
observed above the limit dose.
    The Agency concluded that diflubenzuron is not carcinogenic in 
humans based on lack of evidence of carcinogenicity in rats and mice. 
PCA, a plant metabolite of diflubenzuron, tested positive for splenic 
tumors in male rats and hepatocellular adenomas/carcinomas in male mice 
in a National Toxicology Program (NTP) study. Therefore, EPA has 
treated PCA as a probable human carcinogen. CPU is the major degradate 
found in water and is a significant metabolite in milk. CPU is 
structurally related to monuron (N,N-dimethyl-CPU), a compound 
producing tumors of the kidney and liver in male rats. EPA has assumed 
CPU is a probable human carcinogen as well.
    Specific information on the studies received and the nature of the 
adverse effects caused by diflubenzuron as well as the no-observed-
adverse-effect-level (NOAEL) and the lowest-observed-adverse-effect-
level (LOAEL) from the toxicity studies can be found at http://www.regulations.gov in document, ``Diflubenzuron: Human Health Risk 
Assessment for an Amended Section 3 Registration for the Expanded 
Citrus Crop Group 10-10.'' in docket ID number EPA-HQ-OPP-2012-0515.

B. Toxicological Points of Departure/Levels of Concern

    Once a pesticide's toxicological profile is determined, EPA 
identifies toxicological points of departure (POD) and levels of 
concern (LOC) to use in evaluating the risk posed by human exposure to 
the pesticide. For hazards that have a threshold below which there is 
no appreciable risk, the toxicological POD is used as the basis for 
derivation of reference values for risk assessment. PODs are developed 
based on a careful analysis of the doses in each toxicological study to 
determine the dose at which the NOAEL and the LOAEL are identified. 
Uncertainty/safety factors are used in conjunction with the POD to 
calculate a safe exposure level--generally referred to as a population-
adjusted dose (PAD) or a reference dose (RfD)--and a safe margin of 
exposure (MOE). For non-threshold risks, the Agency assumes that any 
amount of exposure will lead to some degree of risk. Thus, the Agency 
estimates risk in terms of the probability of an occurrence of the 
adverse effect expected in a lifetime. For more information on the 
general principles EPA uses in risk characterization and a complete 
description of the risk assessment process, see http://www.epa.gov/pesticides/factsheets/riskassess.htm.
    A summary of the toxicological endpoints for diflubenzuron used for 
human risk assessment is shown in Table 1 and 2 of this unit.

[[Page 5296]]

  Table 1--Summary of Toxicological Doses and Endpoints for Diflubenzuron for Use in Dietary Human Health Risk
                                                   Assessments
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                                                                                                   Study and
        Exposure/scenario                 POD          Uncertainty/ FQPA   RfD, PAD, LOC for     toxicological
                                                        safety factors      risk assessment         effects
----------------------------------------------------------------------------------------------------------------
Acute dietary all populations...  N/A...............  N/A...............  No appropriate endpoint attributable
                                                                           to single exposure was available
----------------------------------------------------------------------------------------------------------------
Chronic dietary all populations.  NOAEL = 2 mg/kg/    UFA = 10X           cPAD = chronic RfD  Chronic dog study
                                   day.               UFH = 10X.........   FQPA SF = 0.02 mg/  00146174.
                                                      FQPA SF = 1X......   kg/day.            LOAEL = 10 mg/kg/
                                                                                               day based on
                                                                                               methemoglobinemia
                                                                                               and
                                                                                               sulfhemoglobinemi
                                                                                               a.
----------------------------------------------------------------------------------------------------------------
Cancer (all routes)               Classification: ``Group E'' evidence of non- carcinogenicity for humans.
 Diflubenzuron.
----------------------------------------------------------------------------------------------------------------
Cancer (oral, dermal,             PCA ``Group B2''    N/A...............  NTP oral mouse study.
 inhalation).                      probably human
                                   carcinogen Q1*.
                                  1.12 x 10-1 (mg/kg/
                                   day)-1.
----------------------------------------------------------------------------------------------------------------
Cancer (oral, dermal,             CPU Q1* based on    N/A...............  NTP oral rat study.
 inhalation).                      monuron a
                                   structural analog
                                   and the Q1* 1.52
                                   x 10-2.
----------------------------------------------------------------------------------------------------------------
Point of Departure (POD) = A data point or an estimated point that is derived from observed dose-response data
  and used to mark the beginning of extrapolation to determine risk associated with lower environmentally
  relevant human exposures.
NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertainty factor.
  UFA = extrapolation from animal to human (interspecies). UFH = potential variation in sensitivity among
  members of the human population (intraspecies). FQPA SF = Food Quality Protection Act Safety Factor. PAD =
  population adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE = margin of exposure. LOC = level
  of concern. N/A = not applicable.

 Table 2--Summary of Toxicological Doses and Endpoints for Diflubenzuron for Use in Residential and Occupational
                                          Human Health Risk Assessments
----------------------------------------------------------------------------------------------------------------
                                                                           Level of concern        Study and
        Exposure/scenario                 POD            Uncertainty/          for risk          toxicological
                                                            factors           assessment            effects
----------------------------------------------------------------------------------------------------------------
Short- and intermediate-term      N/A...............  N/A...............  N/A...............  These endpoints
 incidental oral (1 day-6                                                                      were not
 months) (residential).                                                                        evaluated. There
                                                                                               are no registered
                                                                                               uses of
                                                                                               diflubenzuron
                                                                                               which result in
                                                                                               significant
                                                                                               residential
                                                                                               exposure.
Short-term dermal (1-30 days)     NOAEL = 500 mg/kg/  UFA = 10X.........  LOC for MOE = 100.  21-day rat dermal
 (occupational).                   day.               UFH = 10X.........                      LOAEL = 1,000 mg/
                                                                                               kg/day based on
                                                                                               methemoglobinemia
                                                                                               .
Dermal intermediate term (1-6     NOAEL = 2 mg/kg/    UFA = 10X.........  LOC for MOE = 100.  13--week oral dog
 months).                          day.               UFH = 10X.........                      LOAEL = 6.4 mg/kg/
                                                      dermal absorption:                       day based on
                                                       0.5%.                                   methemoglobinemia
                                                                                               .
Inhalation short term (1-30       NOAEL = 0.109 mg/L  UFA = 10X.........  LOC for MOE = 100.  28-day Inhalation
 days).                           NOAEL = 20.30 \1\   UFH = 10X.........                       rat study.
                                   mg/kg/day.                                                 No effect at HDT
                                                                                               \2\, 0.109 mg/L.
Inhalation intermediate term (1-  NOAEL = 0.109 mg/L  UFA = 10X.........  LOC for MOE = 100.  28-day Inhalation
 6 months).                       NOAEL = 20.30 \1\   UFH =10X..........                       rat study.
                                   mg/kg/day.                                                 No effect at HDT,
                                                                                               0.109 mg/L.
Inhalation long term (1-6         NOAEL = 2 mg/kg/    UFA = 10X.........  LOC for MOE = 100.  Chronic dog study.
 months).                          day.               UFH = 10X.........                      LOAEL = 10 mg/kg/
                                                                                               day based on
                                                                                               methemoglobinemia
                                                                                               and
                                                                                               sulfhemoglobinemi
                                                                                               a.
                                 -------------------------------------------------------------------------------
Cancer (all routes).............  Classification: ``Group E'' evidence of non- carcinogenicity for humans.
----------------------------------------------------------------------------------------------------------------
\1\ Conversion from mg/L to oral dose (mg/kg/day) = mg/L x absorption (1.0) x Respiratory Volume (Sprague-Dawley
  rats) for 6 hours/d x Duration of Exposure (5 d/week)/body weight x 7 d/week = 0.109 mg/L x 1.0 x (0.26(RV) x
  6 hrs) x 5 d/wk / 0.236 kg x 7 d/wk = 20.3 mg/kg/day (TXR 0050503).
\2\ Highest Dose Tested.

[[Page 5297]]

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to diflubenzuron, EPA considered exposure under the 
petitioned-for tolerances as well as all existing diflubenzuron 
tolerances in 40 CFR 180.377. EPA assessed dietary exposures from 
diflubenzuron in food as follows:
    i. Acute exposure. Quantitative acute dietary exposure and risk 
assessments are performed for a food-use pesticide if a toxicological 
study has indicated the possibility of an effect of concern occurring 
as a result of a 1-day or single exposure. No such effects were 
identified in the toxicological studies for diflubenzuron; therefore, a 
quantitative acute dietary exposure assessment is unnecessary.
    ii. Chronic exposure. In conducting the chronic non-cancer dietary 
exposure assessment, EPA used the food consumption data from the United 
States Department of Agriculture (USDA) National Health and Nutrition 
Examination Survey, ``What We Eat in America'' (NHANES/WWEIA) from 2003 
through 2008. As to residue levels in food, EPA used the assumption 
that diflubenzuron residues are present in most commodities at 
tolerance levels (including tolerances previously established as well 
as those established in this action) and that 100% of all crops are 
treated. Average field trial residues were assumed for grapefruit, 
lemon, and orange. Tolerances include residues of diflubenzuron, PCA, 
and CPU.
    iii. Cancer. Based on the data summarized in Unit III.A., EPA has 
concluded that diflubenzuron does not pose a cancer risk to humans. 
However, metabolites CPU and PCA are considered probable carcinogens 
and have Q*s assigned to them. Individual cancer dietary exposure 
analyses were conducted for each metabolite. For PCA, average percent 
crop treated (PCT) was used for some commodities. One-half the Limit of 
Quantitation (LOQ) was used for estimating PCA residues on the majority 
of crops because most crops did not contain detectable residues of PCA. 
Average field trial residue was used for mushrooms. The CPU cancer 
dietary analysis focused on CPU residues in milk because metabolism 
studies indicate that diflubenzuron metabolizes to CPU in milk. EPA 
assumed that 100% of milk commodities contained CPU at \1/2\ the LOQ. 
One-half the LOQ was used since detectable residues of CPU were not 
found in the feeding study.
    iv. Anticipated residue and PCT information. Section 408(b)(2)(E) 
of FFDCA authorizes EPA to use available data and information on the 
anticipated residue levels of pesticide residues in food and the actual 
levels of pesticide residues that have been measured in food. If EPA 
relies on such information, EPA must require pursuant to FFDCA section 
408(f)(1) that data be provided 5 years after the tolerance is 
established, modified, or left in effect, demonstrating that the levels 
in food are not above the levels anticipated. For the present action, 
EPA will issue such Data Call-Ins as are required by FFDCA section 
408(b)(2)(E) and authorized under FFDCA section 408(f)(1). Data will be 
required to be submitted no later than 5 years from the date of 
issuance of these tolerances.
    Section 408(b)(2)(F) of FFDCA states that the Agency may use data 
on the actual percent of food treated for assessing chronic dietary 
risk only if:
     Condition a: The data used are reliable and provide a 
valid basis to show what percentage of the food derived from such crop 
is likely to contain the pesticide residue.
     Condition b: The exposure estimate does not underestimate 
exposure for any significant subpopulation group.
     Condition c: Data are available on pesticide use and food 
consumption in a particular area, the exposure estimate does not 
understate exposure for the population in such area.
    In addition, the Agency must provide for periodic evaluation of any 
estimates used. To provide for the periodic evaluation of the estimate 
of PCT as required by FFDCA section 408(b)(2)(F), EPA may require 
registrants to submit data on PCT.
    The Agency estimated the PCT for existing uses as follows: Almond 
(10%), apricot (10%), artichoke (50%), cotton (1%), grapefruit (15%), 
oranges (5%), peach (5%), peanut (5%), pear (5%), pecan (2.5%), peppers 
(1%), rice (1%), soybeans (1%), tangerines (5%), and wheat (1%).
    In most cases, EPA uses available data from USDA/National 
Agricultural Statistics Service (NASS), proprietary market surveys, and 
the National Pesticide Use Database for the chemical/crop combination 
for the most recent 6 to 7 years. EPA uses an average PCT for chronic 
dietary risk analysis. The average PCT figure for each existing use is 
derived by combining available public and private market survey data 
for that use, averaging across all observations, and rounding to the 
nearest 5%, except for those situations in which the average PCT is 
less than one. In those cases, 1% is used as the average PCT and 2.5% 
is used as the maximum PCT. EPA uses a maximum PCT for acute dietary 
risk analysis. The maximum PCT figure is the highest observed maximum 
value reported within the recent 6 years of available public and 
private market survey data for the existing use and rounded up to the 
nearest multiple of 5%.
    The Agency believes that the three conditions discussed in Unit 
III.C.1.iv. have been met. With respect to Condition a, PCT estimates 
are derived from Federal and private market survey data, which are 
reliable and have a valid basis. The Agency is reasonably certain that 
the percentage of the food treated is not likely to be an 
underestimation. As to Conditions b and c, regional consumption 
information and consumption information for significant subpopulations 
is taken into account through EPA's computer-based model for evaluating 
the exposure of significant subpopulations, including several regional 
groups. Use of this consumption information in EPA's risk assessment 
process ensures that EPA's exposure estimate does not understate 
exposure for any significant subpopulation group and allows the Agency 
to be reasonably certain that no regional population is exposed to 
residue levels higher than those estimated by the Agency. Other than 
the data available through national food consumption surveys, EPA does 
not have available reliable information on the regional consumption of 
food to which diflubenzuron may be applied in a particular area.
    2. Dietary exposure from drinking water. The Agency used screening 
level water exposure models in the dietary exposure analysis and risk 
assessment for diflubenzuron in drinking water. These simulation models 
take into account data on the physical, chemical, and fate/transport 
characteristics of diflubenzuron. Further information regarding EPA 
drinking water models used in pesticide exposure assessment can be 
found at http://www.epa.gov/oppefed1/models/water/index.htm.
    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure model.
    Based on the Pesticide Root Zone Model/Exposure Analysis Modeling 
System (PRZM/EXAMS) and Screening Concentration in Ground Water (SCI-
GROW) models, the Estimated Drinking Water Concentrations (EDWC) of 
12.8 microgram/Liter ([mu]g/L) (including diflubenzuron and CPU) was 
used to assess chronic non-cancer dietary risk. CPU cancer risk was 
assessed using the EDWC of 8.81 [mu]g/L.

[[Page 5298]]

    3. From non-dietary exposure. The term ``residential exposure'' is 
used in this document to refer to non-occupational, non-dietary 
exposure (e.g., for lawn and garden pest control, indoor pest control, 
termiticides, and flea and tick control on pets).
    Although there are no registered homeowner uses, there are 
registered uses for professional applications to outdoor trees and 
ornamentals in residential areas. However, given the effects in the 21-
day dermal toxicity study were only observed at the limit dose (1,000 
mg/kg/day) and the dermal absorption is extremely low (0.5%) as well as 
the intermittent potential for post-application residential exposure to 
ornamentals (i.e., contact with ornamentals every day is not likely), a 
residential post-application assessment is not required at this time.
    4. Cumulative effects from substances with a common mechanism of 
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when 
considering whether to establish, modify, or revoke a tolerance, the 
Agency consider ``available information'' concerning the cumulative 
effects of a particular pesticide's residues and ``other substances 
that have a common mechanism of toxicity.''
    EPA has not found diflubenzuron to share a common mechanism of 
toxicity with any other substances, and diflubenzuron does not appear 
to produce a toxic metabolite produced by other substances. For the 
purposes of this tolerance action, therefore, EPA has assumed that 
diflubenzuron does not have a common mechanism of toxicity with other 
substances. For information regarding EPA's efforts to determine which 
chemicals have a common mechanism of toxicity and to evaluate the 
cumulative effects of such chemicals, see EPA's Web site at http://www.epa.gov/pesticides/cumulative.

D. Safety Factor for Infants and Children

    1. In general. Section 408(b)(2)(C) of FFDCA provides that EPA 
shall apply an additional tenfold (10X) margin of safety for infants 
and children in the case of threshold effects to account for prenatal 
and postnatal toxicity and the completeness of the database on toxicity 
and exposure unless EPA determines based on reliable data that a 
different margin of safety will be safe for infants and children. This 
additional margin of safety is commonly referred to as the Food Quality 
Protection Act (FQPA) SF. In applying this provision, EPA either 
retains the default value of 10X, or uses a different additional SF 
when reliable data available to EPA support the choice of a different 
factor.
    2. Prenatal and postnatal sensitivity. Based on the available 
developmental toxicity studies in rats and rabbits and the reproduction 
study, there is no increased susceptibility to fetuses exposed in 
utero.
    3. Conclusion. EPA has determined that reliable data show the 
safety of infants and children would be adequately protected if the 
FQPA SF were reduced to 1X. That decision is based on the following 
findings:
    i. The toxicological database for diflubenzuron is complete. The 
toxicity of CPU and PCA is well understood. CPU is less toxic and does 
not affect methemoglobin. PCA does cause methemoglobin formation but is 
similar in potency to diflubenzuron. Therefore, assuming equal toxicity 
of CPU and PCA to diflubenzuron is health protective, additional 
toxicity studies are not required.
    ii. There are no clear signs of neurotoxicity following subchronic 
or chronic dosing in multiple species in the diflubenzuron database; 
therefore, there is no need for any neurotoxicity studies.
    iii. There is no evidence that diflubenzuron results in increased 
susceptibility in in utero rats or rabbits in the prenatal 
developmental studies or in young rats in the 2-generation reproduction 
study.
    iv. The dietary exposure assessment uses conservative assumptions 
which will not underestimate dietary exposure and EPA made conservative 
(protective) assumptions in the ground and surface water modeling used 
to assess exposure to diflubenzuron in drinking water. These 
assessments will not underestimate the exposure and risks posed by 
diflubenzuron.

E. Aggregate Risks and Determination of Safety

    EPA determines whether acute and chronic dietary pesticide 
exposures are safe by comparing aggregate exposure estimates to the 
aPAD and cPAD. For linear cancer risks, EPA calculates the lifetime 
probability of acquiring cancer given the estimated aggregate exposure. 
Short-, intermediate-, and chronic-term risks are evaluated by 
comparing the estimated aggregate food, water, and residential exposure 
to the appropriate PODs to ensure that an adequate MOE exists.
    1. Acute risk. An acute aggregate risk assessment takes into 
account acute exposure estimates from dietary consumption of food and 
drinking water. No adverse effect resulting from a single oral exposure 
was identified and no acute dietary endpoint was selected. Therefore, 
diflubenzuron is not expected to pose an acute risk.
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that chronic exposure to 
diflubenzuron from food and water will utilize 37% of the cPAD for 
children 1 to 2 years old, the population group receiving the greatest 
exposure. There are no residential uses for diflubenzuron.
    3. Short-term risk. Short-term aggregate exposure takes into 
account short-term residential exposure plus chronic exposure to food 
and water (considered to be a background exposure level). A short-term 
adverse effect was identified; however, diflubenzuron is not registered 
for any use patterns that would result in short-term residential 
exposure; therefore, no further assessment of short-term risk is 
necessary.
    4. Intermediate-term risk. Intermediate-term aggregate exposure 
takes into account intermediate-term residential exposure plus chronic 
exposure to food and water (considered to be a background exposure 
level). An intermediate-term adverse effect was identified; however, 
diflubenzuron is not registered for any use patterns that would result 
in intermediate-term residential exposure; therefore, no further 
assessment of intermediate-term risk is necessary.
    5. Aggregate cancer risk for U.S. population. Based on the lack of 
evidence of carcinogenicity in two adequate rodent carcinogenicity 
studies, diflubenzuron is not expected to pose a cancer risk to humans. 
However, metabolites CPU and PCA are considered probable carcinogens 
and have Q*s assigned to them. Individual cancer dietary exposure 
analyses were conducted for each metabolite. The cancer assessment for 
PCA includes food only (not present in drinking water). The cancer 
assessment for CPU includes milk and water only. For PCA, the cancer 
dietary exposure estimate for the U.S. population is 1 x 
10-\6\. For CPU, the cancer dietary exposure estimate for 
the U.S. population is 3 x 10-\6\.
    EPA generally considers cancer risks in the range of 
10-\6\ or less to be negligible. The precision which can be 
assumed for cancer risk estimates is best described by rounding to the 
nearest integral order of magnitude on the log scale; for example, 
risks falling between 3 x 10\-7\ and 3 x 10-\6\ are 
expressed as risks in the range of 10-\6\. Considering the 
precision with which cancer hazard can be estimated, the 
conservativeness of low-dose linear

[[Page 5299]]

extrapolation, and the rounding procedure described above, cancer risk 
should generally not be assumed to exceed the benchmark level of 
concern of the range of 10-\6\ until the calculated risk 
exceeds approximately 3 x 10-\6\. This is particularly the 
case where some conservatism is maintained in the exposure assessment. 
Although the PCA and CPU exposure risk assessment are refined, they 
retain significant conservatism in that residues in food were estimated 
at \1/2\ LOQ even though no residues were detected in field trials and 
feeding studies, and for some commodities EPA assumed 100 PCT. 
Accordingly, EPA has concluded the cancer risk for all existing 
diflubenzuron uses, and the uses associated with the tolerances 
established in this action fall within the range of 1 x 
10-\6\ and are thus negligible.
    6. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to the general population, or to infants and children from aggregate 
exposure to diflubenzuron residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methodology (gas chromatography/electron 
capture detection (ECD) and high-performance liquid chromatography/
ultraviolet (HPLC/UV)) is available to enforce the tolerance 
expression.

B. International Residue Limits

    In making its tolerance decisions, EPA seeks to harmonize U.S. 
tolerances with international standards whenever possible, consistent 
with U.S. food safety standards and agricultural practices. EPA 
considers the international maximum residue limits (MRLs) established 
by the Codex Alimentarius Commission (Codex), as required by FFDCA 
section 408(b)(4). The Codex Alimentarius is a joint United Nations 
Food and Agriculture Organization/World Health Organization food 
standards program, and it is recognized as an international food safety 
standards-setting organization in trade agreements to which the United 
States is a party. EPA may establish a tolerance that is different from 
a Codex MRL; however, FFDCA section 408(b)(4) requires that EPA explain 
the reasons for departing from the Codex level.
    The Codex has established MRLs for diflubenzuron, expressed in 
terms of diflubenzuron per se, for many including: Citrus, fruits 0.5 
ppm. This MRL is different than the citrus crop group tolerance being 
established for diflubenzuron in this action.
    Numerical compatibility with Codex is not possible as the good 
agricultural practices used for the Codex MRL are different from the 
proposed use pattern in the U.S. Additionally, the tolerance expression 
for the Codex MRL and the U.S. tolerance are not the same, only the 
U.S. tolerance contains the CPU and PCA metabolites. EPA is re-
examining whether it can harmonize the U.S. tolerance expression with 
the Codex MRL, but making this change alone would not harmonize the 
numerical difference.

C. Revisions to Petitioned-For Tolerances

    EPA is revising the tolerance expression to clarify that, as 
provided in FFDCA section 408(a)(3), the tolerance covers metabolites 
and degradates of diflubenzuron not specifically mentioned; and that 
compliance with the specified tolerance levels is to be determined by 
measuring only the specific compounds mentioned in the tolerance 
expression. Therefore, the tolerance expression for diflubenzuron will 
be revised under 40 CFR 180.377 (a)(1), (a)(2), and (b) (see the 
regulatory text of this document).

V. Conclusion

    Therefore, tolerances are established for residues of 
diflubenzuron, (N-[[(4-chlorophenyl)amino]carbonyl]-2,6-
difluorobenzimide) in or on fruit, citrus, group 10-10 at 3.0 ppm; and 
citrus, oil at 32 ppm. The Agency is removing the currently established 
tolerances for grapefruit, orange, pummel, and tangerine from 40 CFR 
180.377. These tolerances are being replaced by the tolerance for 
fruit, citrus, group 10-10.

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances under FFDCA section 408(d) 
in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled ``Regulatory Planning and 
Review'' (58 FR 51735, October 4, 1993). Because this final rule has 
been exempted from review under Executive Order 12866, this final rule 
is not subject to Executive Order 13211, entitled ``Actions Concerning 
Regulations That Significantly Affect Energy Supply, Distribution, or 
Use'' (66 FR 28355, May 22, 2001) or Executive Order 13045, entitled 
``Protection of Children from Environmental Health Risks and Safety 
Risks'' (62 FR 19885, April 23, 1997). This final rule does not contain 
any information collections subject to OMB approval under the Paperwork 
Reduction Act (PRA) (44 U.S.C. 3501 et seq.), nor does it require any 
special considerations under Executive Order 12898, entitled ``Federal 
Actions to Address Environmental Justice in Minority Populations and 
Low-Income Populations'' (59 FR 7629, February 16, 1994).
    Since tolerances and exemptions that are established on the basis 
of a petition under FFDCA section 408(d), such as the tolerance in this 
final rule, do not require the issuance of a proposed rule, the 
requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et 
seq.), do not apply.
    This final rule directly regulates growers, food processors, food 
handlers, and food retailers, not States or tribes, nor does this 
action alter the relationships or distribution of power and 
responsibilities established by Congress in the preemption provisions 
of FFDCA section 408(n)(4). As such, the Agency has determined that 
this action will not have a substantial direct effect on States or 
tribal governments, on the relationship between the national government 
and the States or tribal governments, or on the distribution of power 
and responsibilities among the various levels of government or between 
the Federal Government and Indian Tribes. Thus, the Agency has 
determined that Executive Order 13132, entitled ``Federalism'' (64 FR 
43255, August 10, 1999) and Executive Order 13175, entitled 
``Consultation and Coordination with Indian Tribal Governments'' (65 FR 
67249, November 9, 2000) do not apply to this final rule. In addition, 
this final rule does not impose any enforceable duty or contain any 
unfunded mandate as described under Title II of the Unfunded Mandates 
Reform Act of 1995 (UMRA) (2 U.S.C. 1501 et seq.).
    This action does not involve any technical standards that would 
require Agency consideration of voluntary consensus standards pursuant 
to section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (NTTAA) (15 U.S.C. 272 note).

VII. Congressional Review Act

    Pursuant to the Congressional Review Act (5 U.S.C. 801 et seq.), 
EPA will submit a report containing this rule and other required 
information to the U.S. Senate, the U.S. House of Representatives, and 
the Comptroller General of the United States prior to publication of 
the rule in the Federal

[[Page 5300]]

Register. This action is not a ``major rule'' as defined by 5 U.S.C. 
804(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: January 17, 2014.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

    Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

0
1. The authority citation for part 180 continues to read as follows:

    Authority:  21 U.S.C. 321(q), 346a and 371.

0
2. In Sec.  180.377:
0
a. Revise the introductory text in paragraph (a)(1).
0
b. Remove ``Grapefruit'', ``Orange sweet'', and ``Tangerine'' from the 
table in paragraph (a)(1).
0
c. Revise the introductory text in paragraph (a)(2).
0
d. Remove ``Pummelo'', from the table in paragraph (a)(2).
0
e. Add Citrus, oil, and Fruit, citrus, group 10-10 to the table in 
paragraph (a)(2).
0
f. Revise the introductory text in paragraph (b).
    The amendments read as follows:

Sec.  180.377  Diflubenzuron; tolerances for residues.

    (a) General. (1) Tolerances are established for residues of 
diflubenzuron, including its metabolites and degradates, in or on the 
commodities in the table below. Compliance with the tolerance levels 
specified below is to be determined by measuring only diflubenzuron (N-
[[(4-chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide).
* * * * *
    (2) Tolerances are established for residues of the insecticide 
diflubenzuron (N-[[(4-chlorophenyl)amino]carbonyl]-2,6-
difluorobenzamide), in or on the commodities in the table below. 
Compliance with the tolerance levels specified below is to be 
determined by measuring only the sum of diflubenzuron (N-[[(4-
chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide), 4-
chlorophenylyurea and 4-chloroaniline, calculated as the stoichiometric 
equivalent of diflubenzuron, in or on the commodity.

------------------------------------------------------------------------
                                                               Parts per
                          Commodity                             million
------------------------------------------------------------------------
 
                                * * * * *
Citrus, oil.................................................          32
 
                                * * * * *
Fruit, citrus, group 10-10..................................         3.0
 
                                * * * * *
------------------------------------------------------------------------

    (b) Section 18 emergency exemptions. Time-limited tolerances are 
established for residues of the insecticide diflubenzuron (N-[[(4-
chlorophenyl)amino]carbonyl]-2,6- difluorobenzamide) and its 
metabolites, in connection with use of the pesticide under section 18 
emergency exemptions granted by EPA. Compliance with the tolerance 
levels specified below is to be determined by measuring only the sum of 
diflubenzuron (N-[[(4-chlorophenyl)amino]carbonyl]-2,6-
difluorobenzamide), 4-chlorophenylyurea and 4-chloroaniline, calculated 
as the stoichiometric equivalent of diflubenzuron, in or on the 
commodity. The tolerances are specified in the following table, and 
will expire and are revoked on the dates specified.
* * * * *
[FR Doc. 2014-02064 Filed 1-30-14; 8:45 am]
BILLING CODE 6560-50-P