Document ID: EPA-HQ-OPP-2009-0802-0009
Agency: epa
Document Type: Rule
Title: Pesticide Tolerances: 2,6-Diisopropylnaphthalene (2,6-DIPN) and its Metabolites and Degradates
Posted Date: 2012-06-01T04:00Z

[Federal Register Volume 77, Number 106 (Friday, June 1, 2012)]
[Rules and Regulations]
[Pages 32401-32406]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-13203]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2009-0802; FRL-9350-4]

2,6-Diisopropylnaphthalene (2,6-DIPN) and Its Metabolites and 
Degradates; Pesticide Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation amends the tolerances for residues of 2,6-
Diisopropylnaphthalene (2,6-DIPN) and it's metabolites and degradates 
in or on certain commodities discussed in this document. Loveland 
Products, Inc. requested these tolerances under the Federal Food, Drug, 
and Cosmetic Act (FFDCA).

DATES: This regulation is effective June 1, 2012. Objections and 
requests for hearings must be received on or before July 31, 2012, 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-2009-0802, is available either 
electronically through http://www.regulations.gov or in hard copy at 
the OPP Docket in the Environmental Protection Agency Docket Center 
(EPA/DC), located in EPA West, 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: Andrew Bryceland, Biopesticides and 
Pollution Prevention Division (7511P), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave. NW., 
Washington, DC 20460-0001; telephone number: (703) 305-6928; email 
address: bryceland.andrew@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

[[Page 32402]]

pesticide manufacturer. Potentially affected entities may include, but 
are not limited to those engaged in the following activities:
     Crop production (NAICS code 111).
     Animal production (NAICS code 112).
     Food manufacturing (NAICS code 311).
     Pesticide manufacturing (NAICS code 32532).
    This listing is not intended to be exhaustive, but rather to 
provide a guide for readers regarding entities likely to be affected by 
this action. Other types of entities not listed in this unit could also 
be affected. The North American Industrial Classification System 
(NAICS) codes have been provided to assist you and others in 
determining whether this action might apply to certain entities. If you 
have any 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 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://ecfr.gpoaccess.gov/cgi/t/text/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-2009-0802 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 
July 31, 2012. 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 that 
does not contain any 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 a copy of your 
non-CBI objection or hearing request, identified by docket ID number 
EPA-HQ-OPP-2009-0802, 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 Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute.
     Mail: OPP Docket, Environmental Protection Agency Docket 
Center (EPA/DC), Mail Code: 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.htm.

II. Summary of Petition for Tolerance

    In the Federal Register of May 4, 2012 (77 FR 26477) (FRL-9348-3), 
EPA issued a notice pursuant to FFDCA section 408(d)(3), 21 U.S.C. 
346a(d)(3), announcing the filing of a pesticide petition (PP 9F7626) 
by Loveland Products, Inc., 7251 W. 4th St., Greeley, Colorado 80634. 
The petition requested that 40 CFR 180.590 be amended by establishing 
tolerances for residues of the insecticide 2,6-Diisopropylnaphthalene 
(2,6-DIPN) and its metabolites and degradates, 2,6- DIPN and its 
metabolites and degradates, in or on potato, granules/flakes at 5.5 
parts per million (ppm); potato, wet peel at 6.0 ppm; potato, whole at 
2.0 ppm; cattle, fat at 0.2 ppm; cattle, meat at 0.02 ppm; cattle, meat 
byproducts, except fat at 0.02 ppm; goat, fat at 0.2 ppm; goat, meat at 
0.02 ppm; goat, meat byproducts, except fat at 0.02 ppm; horse, fat at 
0.2 ppm; horse, meat at 0.02 ppm; horse, meat byproducts, except fat at 
0.02 ppm; milk, fat at 0.02 ppm; sheep, fat at 0.2 ppm; sheep, meat at 
0.02 ppm and sheep, meat byproducts, except fat at 0.02 ppm. One 
comment was submitted. An anonymous commenter (EPA-HQ-OPP-2009-0802-
0003) generally expressed opposition to EPA granting this tolerance 
specifically because ``it is time to stop allowing so many toxic 
chemicals to poison earth, which end up in American bodies causing 
cancer and other killing deseases and even in breast milk''. After 
conducting a comprehensive assessment of the data and information 
submitted by the petitioner, EPA has concluded there is a reasonable 
certainty that no harm will result to the U.S. population, including 
infants and children, from aggregate exposure to residues of 2,6-DIPN. 
Thus, under the standard in FFDCA section 408(b)(2), a tolerance is 
appropriate. Based upon review of the data supporting the petition, EPA 
has modified the tolerance expressions such that only the parent need 
be included in the tolerance expression for livestock commodities. The 
reason for these changes are explained in Unit IV.C.

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 2,6-Diisopropylnaphthalene 
(2,6-DIPN) and it's metabolites and degradates including exposure 
resulting from the tolerances established by this action. EPA's 
assessment of exposures and risks associated with 2,6-
Diisopropylnaphthalene (2,6-DIPN) and it's metabolites and degradates 
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

B. Toxicological Endpoints

    1. Acute toxicity. While EPA's complete discussion and analysis of 
acute toxicity of 2,6-DIPN can be found in the Federal Register of 
August 8, 2003 (68 FR 47246) (FRL-7321-6), in

[[Page 32403]]

summary, 2,6-DIPN is classified as Toxicity Category IV for the oral 
route of exposure (median lethal dose (LD50) > 5,000 
milligrams per kilogram (mg/kg)).
    2. Short- and intermediate-term toxicity. While EPA's complete 
discussion and analysis of short- and intermediate-term toxicity of 
2,6-DIPN can be found in the Federal Register of August 8, 2003, a 
summary is provided here. The subchronic toxicity study submitted and 
reviewed suggests the endpoint selection (value/dose at which an effect 
was observed) is the 104 milligrams per kilogram per day (mg/kg/day) no 
observed adverse effect level (NOAEL) based on reduced body weight, 
weight gain, and food consumption. Although the developmental toxicity 
study indicated a lower NOAEL (50 mg/kg/day) for the same toxicity, the 
maternal lowest observed adverse effect level (LOAEL) of 150 mg/kg/day 
is between the subchronic NOAEL of 104-121 mg/kg/day and the LOAEL of 
208-245 mg/kg/day. The NOAEL of 50 mg/kg/day may have been appropriate 
for use in characterization of risks for the subpopulation of women of 
childbearing age; however, the response at 50 mg/kg/day in the 
developmental study was minimal, and the observations for toxic effects 
were more thoroughly documented in the subchronic study.
    3. Chronic toxicity. EPA has established the reference dose (RfD) 
for 2,6-DIPN at 1 mg/kg/day. This RfD is based on results from the 
subchronic and developmental toxicity studies described in the Federal 
Register of September 1, 2006 (71 FR 52011) (FRL-8081-9). In support of 
these tolerances, the RfD remains unchanged.
    4. Carcinogenicity. No new study results suggest that 2,6-DIPN is 
carcinogenic. See EPA's complete discussion and analysis in the Federal 
Register of August 8, 2003. Specific information on the studies 
received and the nature of the adverse effects caused by 2,6-
Diisopropylnaphthalene (2,6-DIPN) and its metabolites and degradates as 
well as the NOAEL and the LOAEL from the toxicity studies are discussed 
in the final rule published in the Federal Register of August 8, 2003.

C. 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 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 no adverse effects are observed (the NOAEL) 
and the lowest dose at which adverse effects of concern are identified 
(the LOAEL). 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 2,6-
Diisopropylnaphthalene (2,6-DIPN) and its metabolites and degradates 
used for human risk assessment is discussed in Unit III. of the final 
rule published in the Federal Register of December 16, 2009 (74 FR 
66574) (FRL-8798-5).

 D. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to 2,6-Diisopropylnaphthalene (2,6-DIPN) and its metabolites 
and degradates, EPA considered exposure under the petitioned-for 
tolerances as well as all existing 2,6-Diisopropylnaphthalene (2,6-
DIPN) and its metabolites and degradates tolerances in 40 CFR 180.590. 
EPA assessed dietary exposures from 2,6-Diisopropylnaphthalene (2,6-
DIPN) and its metabolites and degradates 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 
2,6-Diisopropylnaphthalene (2,6-DIPN) and its metabolites and 
degradates; therefore, a quantitative acute dietary exposure assessment 
is unnecessary.
    ii. Chronic exposure. In conducting the chronic dietary exposure 
assessment anticipated residue and/or percent crop treated (PCT) were 
not used.
    Acute dietary 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. 
In the case of 2,6-DIPN, the toxicity database did not indicate an 
acute endpoint, but the 100 mg/kg/day NOAEL from the subchronic 
toxicity study (rounded from 104 mg/kg/day) was used to evaluate 
potential acute dietary exposure as a conservative basis for risk 
characterization. Also, if the 50 mg/kg/day NOAEL from the 
developmental toxicity study had been used to establish an acute RfD, 
this choice would have been inconsistent with the use of the 100 mg/kg/
day NOAEL since it implies that exposure to repeated daily doses at 100 
mg/kg/day is potentially less hazardous than a single dose at 50 mg/kg/
day. Given the minimal nature of the responses in the subchronic and 
developmental toxicity studies, and the fact that the NOAEL from the 
developmental study is only appropriate to the subgroup of females 13-
49 years of age, using the 100 mg/kg/day RfD for the acute and chronic 
dietary assessments is more appropriate for assessing risk for other 
subgroups and the general population. Therefore, a conservative 
interpretation of these endpoints indicated the need for an acute 
dietary exposure assessment. The 100 mg/kg/day endpoint was also 
interpreted as requiring a chronic dietary exposure assessment.
    Acute and chronic dietary exposure assessments for 2,6-DIPN were 
conducted using the Dietary Exposure Evaluation Model software 
(DEEMTM version 1.30), which incorporates consumption data 
from the United States Department of Agriculture's Continuing Surveys 
of Food Intakes by Individuals (CSFII, 1994-1996/1998). For acute 
exposure assessments, individual 1-day food consumption data define an 
exposure distribution, which is expressed as a percentage of the acute 
population adjusted dose (aPAD) (for 2,6-DIPN, aPAD = 0.1 mg/kg/day). 
For chronic exposure and risk assessment, an estimate of the residue 
level in each food or food-form (e.g., orange or orange juice) on the 
commodity residue list is multiplied by the average daily consumption 
estimate for the food or food-form. The resulting residue consumption 
estimate for each food or food-form is summed with the residue 
consumption estimate for all other food or food-forms on the commodity 
residue list to arrive at the total estimated exposure. Exposure 
estimates are expressed as mg/kg body weight/day and as a percent of 
the 2,6-DIPN chronic

[[Page 32404]]

population adjusted dose (cPAD) (0.1 mg/kg/day). These procedures are 
performed for each population subgroup.
    EPA determines whether quantitative cancer exposure and risk 
assessments are appropriate for a food-use pesticide based on the 
weight of the evidence from cancer studies and other relevant data. If 
quantitative cancer risk assessment is appropriate, cancer risk may be 
quantified using a linear or nonlinear approach. If sufficient 
information on the carcinogenic mode of action is available, a 
threshold or nonlinear approach is used and a cancer RfD is calculated 
based on an earlier noncancer key event. If carcinogenic mode of action 
data are not available, or if the mode of action data determines a 
mutagenic mode of action, a default linear cancer slope factor approach 
is utilized.
    Based on the data summarized in Unit III.A., EPA has concluded that 
2,6-DIPN does not pose a cancer risk to humans. Therefore, a dietary 
exposure assessment for the purpose of assessing cancer risk is 
unnecessary.
    iii. Anticipated residue and PCT information. EPA did not use 
anticipated residue and/or PCT information in the dietary assessment 
for 2,6-Diisopropylnaphthalene (2,6-DIPN) and its metabolites and 
degradates. Tolerance level residues and/or 100 PCT were assumed for 
all food commodities.
    2. Dietary exposure from drinking water. Because 2,6-DIPN treatment 
of stored (i.e., post-harvest) potato occurs inside (in warehouses, for 
example), no concern from exposure through water is expected regarding 
acute and chronic dietary risk assessment. For this reason, the dietary 
risk assessment did not include drinking water values.
    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). 2,6-
Diisopropylnaphthalene (2,6-DIPN) and its metabolites and degradates is 
not registered for any specific use patterns that would result in 
residential exposure.
    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 2,6-Diisopropylnaphthalene (2,6-DIPN) and its 
metabolites and degradates to share a common mechanism of toxicity with 
any other substances, and 2,6-Diisopropylnaphthalene (2,6-DIPN) and its 
metabolites and degradates does not appear to produce a toxic 
metabolite produced by other substances. For the purposes of this 
tolerance action, therefore, EPA has assumed that 2,6-
Diisopropylnaphthalene (2,6-DIPN) and its metabolites and degradates 
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.

E. 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 FQPA Safety 
Factor (SF). In applying this provision, EPA either retains the default 
value of 10X, or uses a different additional safety factor when 
reliable data available to EPA support the choice of a different 
factor.
    2. Prenatal and postnatal sensitivity. There were no observed 
prenatal and postnatal effects.
    3. Conclusion. Based on the risk assessments and in consideration 
of residue data, EPA concludes that there is a reasonable certainty 
that no harm will result to the U.S. population, including infants and 
children, from aggregate exposure to residues of 2,6-DIPN, including 
its metabolites and degradates, within the existing tolerance limits 
resulting from post-harvest applications, undertaken in accordance with 
good agricultural practices and EPA-approved labeling, to potatoes. 
Such exposure includes all anticipated dietary exposures and all other 
exposures for which there is reliable information. In arriving at this 
conclusion, EPA has retained the tenfold margin of safety in order to 
adequately account for potential pre- and post-natal toxicity and 
completeness of the data with respect to exposure and toxicity to 
infants and children.

F. Aggregate Risks and Determination of Safety

    EPA determines whether acute and chronic dietary pesticide 
exposures are safe by comparing aggregate exposure estimates to the 
acute PAD (aPAD) and chronic PAD (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, 
2,6-Diisopropylnaphthalene (2,6-DIPN) and it's metabolites and 
degradates is not expected to pose an acute risk.
    2. Chronic risk. There are no residential uses for 2,6-
Diisopropylnaphthalene (2,6-DIPN) and its metabolites and degradates.
    3. Short-term risk. Because no short-term adverse effect was 
identified, 2,6-Diisopropylnaphthalene (2,6-DIPN) and its metabolites 
and degradates is not expected to pose a short-term risk.
    4. Intermediate-term risk. Because no intermediate-term adverse 
effect was identified, 2,6-Diisopropylnaphthalene (2,6-DIPN) and its 
metabolites and degradates is not expected to pose a intermediate-term 
risk.
    5. Aggregate cancer risk for U.S. population. Based on the lack of 
evidence of carcinogenicity in two adequate rodent carcinogenicity 
studies, 2,6-DIPN is not expected to pose a cancer risk to humans.
    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 2,6-Diisopropylnaphthalene (2,6-DIPN) and its metabolites 
and degradates residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Loveland Products, Inc. has proposed a liquid chromatographic/
ultraviolet (LC/UV) detection analytical method for enforcement of 
tolerances for residues of 2,6-DIPN in potatoes and potato peels. While 
tolerances are set for livestock

[[Page 32405]]

commodities, no analytical method is being required for livestock 
commodities based on a re-evaluation of the cattle feeding study and 
the existing ruminant metabolism study which was conducted in goats at 
a feeding level two times the Maximum Reasonable Dietary Burden (MRDB). 
The parent compound DIPN and the metabolites M27 and M29 were 
quantifiable in all edible livestock matrices. In the cattle feeding 
study DIPN was quantifiable at exaggerated feeding levels, and at the 
MRDB in fat. The results of the metabolism and feeding studies indicate 
that fat will likely have the highest residues of any of the livestock 
matrices, and USDA monitors fat for pesticide residues accessed 5/10/
12). Therefore, the parent will be an adequate marker for misuse, 
particularly with regard to fat which is the commodity most likely to 
have residues and most likely to be monitored. Accordingly, the residue 
definition for the tolerance expression can be modified to include the 
parent compound only.
    The method (entitled, ``Liquid Chromatographic Analysis for the 
Determination of 2,6-Diisopropylnaphthalene (DIPN) in Potatoes and 
Liquid Chromatographic Analysis for the Determination of 2,6-
Diisopropylnaphthalene (DIPN) in Potato Peels'' (Platte Report Number 
CARDC-1298-DIPN)) was used for the determination of residues of 2,6-
DIPN in potatoes and potato peels.
    The method includes instructions and chromatograms for analysis of 
samples of potatoes and potato peels. Briefly, samples are extracted 
with acetonitrile. The extracts are partitioned with hexane. The 
acetonitrile part is discarded. The hexane part is roto-evaporated to 
dryness. The residues are reconstituted in hexane and purified using a 
Florisil column. The residues are roto-evaporated to dryness and 
reconstituted in acetonitrile. The samples are filtered through 
Acrodisc[supreg] LC polyvinylidene difluoride (PVDF) 0.45 micrometer 
([mu]m) filters and analyzed by high performance liquid chromatography 
(HPLC) with ultraviolet (UV) detection at 254 nanometers (nm) using a 
Zorbax ODS column.
    The validated limit of quantitation (LOQ) is 0.01 ppm for 2,6-DIPN 
in potatoes and 0.02 ppm in potato peels. The reported limits of 
detection (LODs) were 0.001 ppm for 2,6-DIPN in potatoes and potato 
peels. The method does not include instructions for confirmatory 
analysis. Method validation data for the LC/UV method demonstrated 
adequate method recoveries of residues of 2,6-DIPN. Potato samples were 
fortified with 2,6-DIPN at levels of 0.01 ppm, 0.02 ppm, 0.05 ppm, and 
50 ppm. Samples were analyzed at the limit of quantitation of 0.01 ppm. 
Overall, recovery ranges (and CVs) from these matrices were 77.9-123.2 
(13.9%) for 2,6-DIPN. Potato peel samples were fortified with 2,6-DIPN 
at levels of 0.02 ppm, 0.05 ppm, and 0.2 ppm. Samples were analyzed at 
the limit of quantitation of 0.02 ppm. Overall, recovery ranges (and 
CVs) from these matrices were 83.2-96.1 (5.3%) for 2,6-DIPN.
    Acceptable independent laboratory validation is available for this 
method using potato and potato peel samples. As described in this unit, 
an adequate enforcement methodology (liquid chromatographic/ultraviolet 
detection analytical method) is available to enforce the tolerance 
expression for potatoes and potato peels only.
    The radiovalidation data for HPLC/UV(CARDC-1298-DIPN) for the 
determination of residues of 2,6-DIPN in potatoes and potato peels 
adequately recovered residues of 2,6-DIPN from samples of whole potato 
and potato peels with the treatment of the active ingredient. 
Multiresidue testing for 2,6-DIPN showed that the multiresidue methods 
are not adequate for enforcement purposes since 2,6-DIPN was not 
recovered through any of the protocols.
    The method may be requested from: Chief, Analytical Chemistry 
Branch, Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD 
20755-5350; telephone number: (410) 305-2905; email address: 
residuemethods@epa.gov.

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 not established a MRL for 2,6-Diisopropylnaphthalene 
(2,6-DIPN) and its metabolites and degradates.

C. Revisions to Petitioned-For Tolerances

    Time-limited tolerances for 2,6-DIPN are set to expire on May 18, 
2012 (40 CFR 180.590). In consideration of whether or not the continued 
use of the active ingredient when used on potatoes would impose further 
risks to human health, EPA has reviewed newly submitted data/
information multiresidue testing for 2,6-DIPN and radiovalidation of 
the analytical method and multiresidue testing method for determination 
of 2,6-DIPN in potato and potato peels as well as re-evaluated existing 
data/information in support of a full tolerance without time 
limitations. Receipt of this information satisfied the conditions of 
registration.
    In the previous time limited tolerance, EPA determined that an 
acceptable revised enforcement analytical method for 2,6-
Diisopropylnaphthalene (2,6-DIPN) and two metabolites (M27 and M29) in 
livestock commodities must be submitted. EPA also determined that 
radiovalidation data for 2,6-DIPN and its metabolites (M27 and M29) 
must also be submitted. These data have already been generated and 
final reports of these studies are anticipated to be submitted to the 
Agency by or before December 2012. Although EPA has requested 
additional data, EPA has revisited its original decision that the 
tolerance expression include two of the metabolites in addition to the 
parent compound. Based on this re-evaluation, EPA has decided to limit 
the tolerance expression to DIPN only. Feeding studies demonstrate that 
DIPN is quantifiable in all animal commodities. The highest residues 
are found in fat, and residues in fat were quantifiable without use of 
exaggerated feeding studies. Fat is also the commodity most frequently 
monitored for tolerance violative residues. Accordingly, EPA concludes 
that limiting the tolerance expression to parent only will be 
appropriate as a tolerance level for monitoring compliance with label 
application instructions for DIPN (the basis on which the safety 
determination for this tolerance was made). (Memorandum from C. 
Ollinger EPA/OPP/HED to L. Hollis EPA/OPP/BPPD dated May 11, 2012).

V. Conclusion

    Therefore, the tolerances for residues of 2,6-
Diisopropylnaphthalene (2,6-DIPN) and its metabolites and degradates, 
are amended, in or on potato, granules/flakes at 5.5 parts per million 
(ppm); potato, wet peel at 6.0

[[Page 32406]]

ppm; potato, whole at 2.0 ppm; cattle, fat at 0.2 ppm; cattle, meat at 
0.02 ppm; cattle, meat byproducts, except fat at 0.02 ppm; goat, fat at 
0.2 ppm; goat, meat at 0.02 ppm; goat, meat byproducts, except fat at 
0.02 ppm; horse, fat at 0.2 ppm; horse, meat at 0.02 ppm; horse, meat 
byproducts, except fat at 0.02 ppm; milk, fat at 0.02 ppm; sheep, fat 
at 0.2 ppm; sheep, meat at 0.02 ppm and sheep, meat byproducts, except 
fat at 0.02 ppm.
    Modification of the residue definition based on re-examination of 
existing data as described in Unit IV.A. and D., also require 
modification of the tolerance level. Residues in milk, skim milk, 
cream, meat, liver, and kidney will be below the limit of quantitation 
(LOQ) of 0.02 ppm. Therefore, the tolerance may be set at 0.02 ppm. 
Residues are likely to be quantifiable in fat. HED recommends a level 
of 0.2 ppm. This is based on the maximum residue of 0.095 from the 8.9 
ppm feeding level (0.6x the MRDB) extrapolated to the 1x feeding level, 
(equal to 0.158 ppm) and rounded up to 0.2 ppm. The existing tolerances 
for DIPN residues on hog commodities may be revoked, since potatoes are 
no longer considered a major feed item for swine (memorandum from C. 
Ollinger (EPA/OPP/HED to L. Hollis EPA/OPP/BPPD dated May 11, 2012).

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) (Pub. L. 104-4).
    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), Public Law 104-113, section 12(d) (15 U.S.C. 272 
note).

VII. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report to each House of the Congress and to 
the Comptroller General of the United States. 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 this final rule in the Federal 
Register. This final rule 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: May 16, 2012.
Keith A. Matthews,
Director, Biopesticides and Pollution Prevention 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. Section 180.590, paragraph (a) is revised to read as follows:

Sec.  14;180.590  2,6-Diisopropylnaphthalene (2,6-DIPN); tolerances for 
residues.

    (a) General. Tolerances are established for residues of the growth 
inhibitor 2,6-DIPN, including its metabolites and degradates, in or on 
the commodities in the following table. Compliance with the tolerance 
levels specified in the following table is to be determined by 
measuring only 2,6-Diisopropylnaphthalene.

------------------------------------------------------------------------
                                                               Parts per
                          Commodity                             million
------------------------------------------------------------------------
Cattle, fat.................................................        0.2
Cattle, meat................................................        0.02
Cattle, meat byproducts, except fat.........................        0.02
Goat, fat...................................................        0.2
Goat, meat..................................................        0.02
Goat, meat byproducts, except fat...........................        0.02
Horse, fat..................................................        0.2
Horse, meat.................................................        0.02
Horse, meat byproducts, except fat..........................        0.02
Milk, fat...................................................        0.02
Potato, granules/flakes.....................................        5.5
Potato, wet peel............................................        6.0
Potato, whole...............................................        2.0
Sheep, fat..................................................        0.2
Sheep, meat.................................................        0.02
Sheep, meat byproducts, except fat..........................        0.02
------------------------------------------------------------------------

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[FR Doc. 2012-13203 Filed 5-31-12; 8:45 am]
BILLING CODE 6560-50-P