Document ID: EPA-HQ-OPP-2008-0806-0003
Agency: epa
Document Type: Rule
Title: Avermectin BINF1/INF and its delta-8,9-isomer; Pesticide Tolerances
Posted Date: 2009-08-07T04:00Z

[Federal Register: August 7, 2009 (Volume 74, Number 151)]
[Rules and Regulations]               
[Page 39545-39551]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07au09-5]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2008-0806; FRL-8427-7]

 
Avermectin B1 and its delta-8,9-isomer; Pesticide 
Tolerances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes tolerances for combined residues 
of avermectin B1 and its delta-8,9-isomer in or on stone 
fruit crop group 12, tree nut crop group 14, pistachio, tuberous and 
corm vegetable crop subgroup 01C, goat fat, hog fat, horse fat, sheep 
fat, cattle fat, and cattle meat byproducts. Existing tolerances for 
cattle, fat and cattle, meat byproducts are revised. Existing 
individual crop tolerances on almond, plum, potato, and walnut are 
deleted and replaced by the establishment of new crop group tolerances. 
Existing tolerances on almond, hulls and plum, prune, dried are 
retained. This regulation also makes a technical correction to 
correctly express the existing tolerances for mint (replace term 
``mint'' with the more specific terms ``peppermint, tops'' and 
``spearmint, tops''). Syngenta Crop Protection, Inc. and Y-TEX 
Corporation requested these tolerances under the Federal Food, Drug, 
and Cosmetic Act (FFDCA).

DATES: This regulation is effective August 7, 2009. Objections and 
requests for hearings must be received on or before October 6, 2009, 
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: EPA has established a docket for this action under docket 
identification (ID) number EPA-HQ-OPP-2008-0806. All documents in the 
docket are listed in the docket index available at http://
www.regulations.gov. Although listed in the index, some information is 
not publicly available, e.g., Confidential Business Information (CBI) 
or other information whose disclosure is restricted by statute. Certain 
other material, such as copyrighted material, is not placed on the 
Internet and will be publicly available only in hard copy form. 
Publicly available docket materials are available in the electronic 
docket at http://www.regulations.gov, or, if only available in hard 
copy, at the OPP Regulatory Public Docket in Rm. S-4400, One Potomac 
Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The Docket 
Facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. The Docket Facility telephone number is (703) 
305-5805.

FOR FURTHER INFORMATION CONTACT: Thomas C. Harris, Registration 
Division (7505P), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001; telephone number: (703) 308-9423; e-mail address: 
harris.thomas@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. 
Potentially affected entities may include, but are not limited to those 
engaged in the following activities:

[[Page 39546]]

     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 Access Electronic Copies of this Document?

    In addition to accessing electronically available documents at 
http://www.regulations.gov, you may access this Federal Register 
document electronically through the EPA Internet under the ``Federal 
Register'' listings at http://www.epa.gov/fedrgstr. You may also access 
a frequently updated electronic version of EPA's tolerance regulations 
at 40 CFR part 180 through the Government Printing Office's e-CFR cite 
at http://www.gpoaccess.gov/ecfr. To access the OPPTS Harmonized 
Guidelines referenced in this document, go directly to the guidelines 
at http://www.epa.gov/opptsfrs/home/guidelin.htm.

C. Can I File an Objection or Hearing Request?

    Under section 408(g) of FFDCA, 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-2008-0806 in the subject line on the first 
page of your submission. All requests must be in writing, and must be 
mailed or delivered to the Hearing Clerk as required by 40 CFR part 178 
on or before October 6, 2009.
    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 that is described in ADDRESSES. Information not marked 
confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA 
without prior notice. Submit this copy, identified by docket ID number 
EPA-HQ-OPP-2008-0806, by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     Mail: Office of Pesticide Programs (OPP) Regulatory Public 
Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460-0001.
     Delivery: OPP Regulatory Public Docket (7502P), 
Environmental Protection Agency, Rm. S-4400, One Potomac Yard (South 
Bldg.), 2777 S. Crystal Dr., Arlington, VA. Deliveries are only 
accepted during the Docket Facility's normal hours of operation (8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays). 
Special arrangements should be made for deliveries of boxed 
information. The Docket Facility telephone number is (703) 305-5805.

II. Petition for Tolerance

    As listed below, EPA published notices pursuant to section 
408(d)(3) of FFDCA, 21 U.S.C. 346a(d)(3), announcing the filing of 
pesticide petitions in the Federal Register requesting that 40 CFR 
180.449 be amended by establishing a tolerance for combined residues of 
the insecticide/miticide avermectin B1 (a mixture of 
avermectins containing greater than or equal to 80% avermectin 
B1a (5-O-demethyl avermectin A1) and less than or 
equal to 20% avermectin B1b (5-O-demethyl-25-de (1-
methylpropyl)-25-(1-methylethyl) avermectin A1)), and its 
delta-8,9-isomer, as listed below. Avermectin B1 is also 
referred to as abamectin. Each notice included a summary of the 
petition prepared by the registrant listed. There were no comments 
received in response to these notices of filing.
    September 27, 2000, 65 FR 58080, FRL-6746-4, PP 0F6146. This 
petition was filed by Novartis Crop Protection, Inc. (now Syngenta Crop 
Protection, Inc.), P.O. Box 18300, Greensboro, NC 27419-8300 for 
tolerances of avermectin B1 and its delta-8,9-isomer in or 
on grass forage at 0.001 ppm, grass hay at 0.001 ppm, stone fruit crop 
group 12 at 0.015 ppm, tree nut crop group 14 at 0.005 ppm, pistachio 
at 0.005 ppm, and the tuberous and corm vegetable crop subgroup 01C at 
0.005 ppm. Tolerances for avocado and mint which were also requested in 
that notice were established earlier (see February 16, 2005, 70 FR 
7876).
    Based upon EPA review of the data supporting the petition, the 
petition was subsequently amended to request permanent tolerances for 
avermectin B1 and its delta-8,9-isomer at the revised levels 
as follow: Stone fruit crop group 12 at 0.09 ppm, tree nut crop group 
14 at 0.01 ppm, pistachios at 0.01 ppm, tuberous and corm vegetables 
crop subgroup 01C at 0.01 ppm, goat fat at 0.01 ppm, hog fat at 0.01 
ppm, horse fat at 0.01 ppm, and sheep fat at 0.01 ppm. The tolerance 
requests for grass hay and grass forage were withdrawn pending 
development of further data on grass hay. Existing individual crop 
tolerances on almond, plum, potato, and walnut are deleted and replaced 
by the establishment of new crop group tolerances. Existing tolerances 
on almond, hulls and plum, prune, dried are retained. The proposed 
tolerance levels were raised based on EPA's analysis of the residue 
data, EPA's assessment of the limits of quantitation (LOQs) of the 
analytical methods, current livestock feed items (OPPTS Guideline 
860.100, Table 1 Feedstuffs, June 2008), and/or to coordinate with 
Codex Maximum Residue Limits (MRLs) (see Unit IV.B.).
    December 3, 2008, 73 FR 73648, FRL-8391-3, PP 8F7454. This petition 
was filed by Y-TEX Corporation, 1825 Big Horn Avenue, P.O. Box 1450, 
Cody, WY 82414, and proposes to amend the tolerances in 40 CFR 180.449 
by increasing the tolerances of avermectin B1 and its delta-
8,9-isomer in or on cattle fat from 0.015 ppm to 0.03 ppm and cattle 
meat byproducts from 0.02 ppm to 0.06 ppm. These tolerances support use 
of avermectin in cattle ear tags.
    This regulation also makes a technical amendment to correctly 
express the existing tolerances for mint which were established in the 
final rule published on February 16, 2005 (70 FR 7876) (FRL-7695-7). 
That rule listed the tolerance as ``mint'' at 0.010 ppm. The correct 
terminology is ``peppermint, tops'' at 0.010 ppm and ``spearmint, 
tops'' at 0.010 ppm.

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

[[Page 39547]]

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 section 408(b)(2)(D) of FFDCA, and the factors 
specified in section 408(b)(2)(D) of FFDCA, 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 the petitioned-for 
tolerances for combined residues of avermectin B1 and its 
delta-8,9-isomer on stone fruit crop group 12 at 0.09 ppm, tree nut 
crop group 14 at 0.01 ppm, pistachios at 0.01 ppm, tuberous and corm 
vegetables crop subgroup 01C at 0.01 ppm, goat fat at 0.01 ppm, hog fat 
at 0.01 ppm, horse fat at 0.01 ppm, sheep fat at 0.01 ppm, cattle fat 
at 0.03 ppm, and cattle meat byproducts at 0.06 ppm. EPA's assessment 
of exposures and risks associated with establishing tolerances 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.
    Avermection B1 (also known as abamectin) has high to 
moderate acute toxicity by the oral route, high acute toxicity by the 
inhalation route, and low acute toxicity by the dermal route. It is 
slightly irritating to the skin, but is not an ocular irritant or a 
dermal sensitizer. In general, the results of available toxicity 
studies with single or repeated dosing indicate that the main target 
organ for avermection B1 is the nervous system, and that 
decreased body weight is also one of the most frequent findings. There 
was no observed estrogen, androgen, or thyroid mediated toxicity. 
Neurotoxicity and developmental effects are detected in multiple 
studies and species of test animals. The dose/response curve is very 
steep in several studies, with severe effects (including death and 
morbid sacrifice) seen at dose levels as low as 0.4 milligrams/
kilogram/day (mg/kg/day) and 0.1 mg/kg/day in rats and mice, 
respectively, following repeated exposures. Increased susceptibility 
(qualitative and/or quantitative) was seen in prenatal developmental 
toxicity studies in mice and rabbits, and an increase in quantitative 
and qualitative susceptibility was also seen in the rat reproductive 
toxicity studies. Review of acceptable oncogenicity and mutagenicity 
studies provide no indication that avermection B1 is 
carcinogenic or mutagenic.
    Specific information on the studies received and the nature of the 
adverse effects caused by avermectin B1 and its delta-8,9-
isomer 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 the ``Abamectin, 
Revised Human Health Risk Assessment for Proposed Uses on Pasture and 
Rangeland Grass, Stone Fruit Crop Group 12, Tree Nut Crop Group 14, 
Pistachio, Tuberous and Corm Vegetables Subgroup 01C, and Request for 
Cattle Ear Tag Use,'' at page 18 in docket ID number EPA-HQ-OPP-2008-
0806.

B. Toxicological Endpoints

    For hazards that have a threshold below which there is no 
appreciable risk, a toxicological point of departure (POD) is 
identified as the basis for derivation of reference values for risk 
assessment. The POD may be defined as the highest dose at which no 
adverse effects are observed (the NOAEL) in the toxicology study 
identified as appropriate for use in risk assessment. However, if a 
NOAEL cannot be determined, the lowest dose at which adverse effects of 
concern are identified (the LOAEL) or a Benchmark Dose (BMD) approach 
is sometimes used for risk assessment. Uncertainty/safety factors (UFs) 
are used in conjunction with the POD to take into account uncertainties 
inherent in the extrapolation from laboratory animal data to humans and 
in the variations in sensitivity among members of the human population 
as well as other unknowns. Safety is assessed for acute and chronic 
dietary risks by comparing aggregate food and water exposure to the 
pesticide to the acute population adjusted dose (aPAD) and chronic 
population adjusted dose (cPAD). The aPAD and cPAD are calculated by 
dividing the POD by all applicable UFs. Aggregate short-, intermediate-
, and chronic-term risks are evaluated by comparing food, water, and 
residential exposure to the POD to ensure that the margin of exposure 
(MOE) called for by the product of all applicable UFs is not exceeded. 
This latter value is referred to as the Level of Concern (LOC).
    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 
greater than that 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 avermectin 
B1 and its delta-8,9-isomer used for human risk assessment 
can be found at http://www.regulations.gov in the document ``Abamectin, 
Revised Human Health Risk Assessment for Proposed Uses on Pasture and 
Rangeland Grass, Stone Fruit Crop Group 12, Tree Nut Crop Group 14, 
Pistachio, Tuberous and Corm Vegetables Subgroup 01C, and Request for 
Cattle Ear Tag Use,'' at page 25 in docket ID number EPA-HQ-OPP-2008-
0806.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. In evaluating dietary 
exposure to avermectin B1 and its delta-8,9-isomer, EPA 
considered exposure under the petitioned-for tolerances as well as all 
existing avermectin B1 and its delta-8,9-isomer tolerances 
in (40 CFR 180.449). EPA assessed dietary exposures from avermectin 
B1 and its delta-8,9-isomer 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.
    In estimating acute dietary exposure, EPA used food consumption 
information from the United States Department of Agriculture (USDA) 
1994-1996 and 1998 Nationwide Continuing Surveys of Food Intake by 
Individuals (CSFII). As to residue levels in food, EPA used a 
probabilistic distribution of anticipated residues derived from field 
trial data for all commodities. Default processing factors and maximum 
surveyed percent crop treated (PCT) were used as available. See Unit 
C.1.iv. below for full listing of PCTs.
    ii. Chronic exposure. In conducting the chronic dietary exposure 
assessment EPA used the food consumption data from the USDA 1994-1996 
and 1998 CSFII. As to residue levels in food, EPA

[[Page 39548]]

used point estimates of anticipated residues derived from field trial 
data for all commodities. Default processing factors and average 
surveyed percent crop treated (PCT) were used as available. Also, 
residues of avermectin B1 and its delta-8,9-isomer in foods 
exposed in a food-handling establishment were assumed to be 0.0002 ppm 
which is one-half the Limit of Detection (LOD). See Unit C.1.iv. below 
for full listing of PCTs.
    iii. Cancer. Based on the absence of a significant increase in 
tumor incidence in two rodent studies, EPA classified avermectin 
B1 as ``not likely to be carcinogenic to humans'' and, thus, 
an exposure assessment for evaluating cancer risk is unnecessary.
    iv. Anticipated residue and percent crop treated (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 used PCT information as follows (average and maximum, 
respectively):

------------------------------------------------------------------------
                                                    Percent Crop Treated
                                                            (PCT)
                     Commodity                     ---------------------
                                                     Average    Maximum
------------------------------------------------------------------------
Almond                                                     50         75
------------------------------------------------------------------------
Apple                                                       5         10
------------------------------------------------------------------------
Avocado                                                    40         60
------------------------------------------------------------------------
Cantaloupe                                                 15         30
------------------------------------------------------------------------
Celery                                                     40         65
------------------------------------------------------------------------
Cottonseed oil                                              5          5
------------------------------------------------------------------------
Cucumber                                                    5         10
------------------------------------------------------------------------
Grape                                                       5         15
------------------------------------------------------------------------
Grape, raisin                                               5         15
------------------------------------------------------------------------
Grapefruit                                                 60         80
------------------------------------------------------------------------
Honeydew                                                   15         30
------------------------------------------------------------------------
Hop                                                        85        100
------------------------------------------------------------------------
Lemon                                                      30         50
------------------------------------------------------------------------
Lettuce                                                    10         15
------------------------------------------------------------------------
Orange                                                     20         40
------------------------------------------------------------------------
Pear                                                       65         80
------------------------------------------------------------------------
Pepper                                                     25        100
------------------------------------------------------------------------
Potato                                                      1        2.5
------------------------------------------------------------------------
Pumpkin                                                   2.5          5
------------------------------------------------------------------------
Spinach                                                    20         45
------------------------------------------------------------------------
Squash                                                      5         10
------------------------------------------------------------------------
Strawberry                                                 35         45
------------------------------------------------------------------------
Tangerine                                                  40         45
------------------------------------------------------------------------
Tomato                                                     15        100
------------------------------------------------------------------------
Walnut                                                      5         20
------------------------------------------------------------------------
Watermelon                                                  5         10
------------------------------------------------------------------------

 EPA assumed 100 PCT (both average and maximum) for other crops not 
listed above, and for all livestock commodities. Maximum PCT was used 
for analysis of acute exposure while average PCT was used for analysis 
of chronic exposure.
    In most cases, EPA uses available data from the U.S. Department of 
Agriculture/National Agricultural Statistics Service (USDA/NASS), 
proprietary market surveys, and the National Pesticide Use Database for 
the chemical/crop combination for the most recent 6 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 <1. 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 avermectin B1 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 avermectin B1 and its major soil degradate (a 
mixture of an 8-alpha-hydroxy and a ring opened aldehyde derivative) in 
drinking water. These simulation models take into account data on the 
physical, chemical, and fate/transport characteristics of avermectin 
B1 and its major soil degradate (a mixture of an 8-alpha-
hydroxy and a ring opened aldehyde derivative). 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.
    Based on the Pesticide Root Zone Model/Exposure Analysis Modeling 
System (PRZM/EXAMS) for surface water and Screening Concentration in

[[Page 39549]]

Ground Water (SCI-GROW) models for ground water, the estimated drinking 
water concentrations (EDWCs) of avermectin B1 and its major 
soil degradate (a mixture of an 8-alpha-hydroxy and a ring opened 
aldehyde derivative) for acute exposures are estimated to be 0.464 
parts per billion (ppb) for surface water and 0.00184 ppb for ground 
water; and for chronic exposures for non-cancer assessments are 
estimated to be 0.211 ppb for surface water and 0.00184 ppb for ground 
water.
    Modeled estimates of drinking water concentrations were directly 
entered into the dietary exposure model. For acute dietary risk 
assessment, the water concentration value of 0.464 ppb was used to 
assess the contribution to drinking water. For chronic dietary risk 
assessment, the water concentration of value 0.211 ppb was used to 
assess the contribution to drinking water.
    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).
    Avermectin B1 is currently registered for the following 
uses that could result in residential exposures: Residential lawn 
application for fire ant control, and residential indoor crack and 
crevice application for cockroaches and ants. EPA assessed residential 
exposure as follows. Exposure and risk estimates for homeowners 
applying crack and crevice baits were estimated using the Standard 
Operating Procedure (SOP) for Residential Exposure Assessments. The 
unit exposure from the wettable powder, open mixing and loading 
scenario listed in the SOP for Residential Exposure Assessments was 
used as a surrogate for estimating dermal and inhalation exposure for 
an activity that involves the use of a small syringe-type duster to 
make bait placements along the baseboards and into cracks and crevices. 
The method used for estimating residential applicator exposure is 
believed to produce a high-end estimate of 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 avermectin B1 to share a common 
mechanism of toxicity with any other substances, and avermectin 
B1 does not appear to produce a toxic metabolite produced by 
other substances. For the purposes of this tolerance action, therefore, 
EPA has assumed that avermectin B1 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 website 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 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. Increased susceptibility was 
seen in prenatal developmental toxicity studies in mice and rabbits 
following in utero exposure to avermectin B1. There was also 
an increase in susceptibility in the rat reproductive toxicity study 
and the rat developmental neurotoxicity study.
    3. Conclusion. EPA has retained an additional FQPA SF for chronic/
long-term and short/intermediate-term assessments due to the steepness 
of the dose-response curve and severity of effects (death) at the 
LOAEL. For all risk assessments involving repeat exposures, the 
selected toxicity endpoint is based on the decrease in pup body weight 
seen in the developmental neurotoxicity study and three reproduction 
studies in the rat. Although the study identified a NOAEL for the 
effects observed in the pups, the data clearly indicate that the 
decrease in pup body weight seen at 0.2 mg/kg/day rapidly progresses to 
death at the next higher tested dose level (0.4 mg/kg/day) in both 
reproduction and developmental neurotoxicity studies. The combined data 
from several reproduction toxicity and developmental neurotoxicity 
studies have documented a very narrow dose range from NOAEL (0.12 mg/
kg/day) to adverse effect (0.2 mg/kg/day) to severe adverse effect (0.4 
mg/kg/day). Dose spacing is commonly greater than the 2x between NOAEL 
and LOAEL here, and the 3x difference between the NOAEL and the dose 
that induced mortality in the pups in the developmental neurotoxicity 
study provides little margin of safety for such a severe effect.
    Nonetheless, EPA has determined that reliable data show the safety 
of infants and children would be adequately protected if the 10X FQPA 
safety (SF) were reduced to 3X for chronic/long term and short/
intermediate-term assessments and reduced to 1X for acute assessments. 
This conclusion is based on the following findings:
    i. Retaining an additional 3x FQPA safety factor effectively 
provides a 10x margin between the dose which causes death (0.4 mg/kg/
day) and the NOAEL adjusted by the additional safety factor (0.12 mg/
kg/day/3x = 0.04 mg/kg/day). A dose spacing of 10x between a NOAEL and 
LOAEL is as broad, if not broader, than the dose spacing generally used 
in animal testing and thus removes the residual concern with the 
steepness of the dose response curve and the severe effects seen here.
    ii. This adjusted point of departure (0.04 mg/kg/day) would also 
address the concerns for the increased susceptibility seen at higher 
doses in the two-generation reproduction study in rats (LOAEL = 0.4 mg/
kg/day), prenatal developmental study in CD-1 mice (LOAEL = 0.75 mg/kg/
day), the prenatal developmental toxicity study in rabbits (LOAEL = 2 
mg/kg/day), and the one-generation reproduction study (LOAEL = 0.2 mg/
kg/day).
    iii. The toxicity database for avermectin B1 is 
complete, except for immunotoxicity studies. EPA began requiring 
functional immunotoxicity testing of all food and non-food use 
pesticides on December 26, 2007. To address the issue of an 
immunotoxicity data gap and the associated database uncertainty factor, 
the Agency examined the entire database of avermectin B1 and 
determined that an additional uncertainty factor is not needed to 
account for potential immunotoxicity. Avermectin B1 has not 
been found to induce effects associated with immunotoxicity and 
avermectin B1 does not belong to a class of chemicals that 
would be expected to be immunotoxic. Therefore, based on the above 
considerations, EPA does not believe that conducting a special 
Harmonized Guideline series 870.7800 immunotoxicity study will result 
in a NOAEL less than the NOAELs of 0.5 and 0.12 mg/kg/day already set 
for avermectin B1 acute and repeated

[[Page 39550]]

exposures, respectively. An additional uncertainty factor 
(UFDB) for database uncertainties associated with 
immunotoxicity does not need to be applied at this time.
    iv. With respect to acute dietary exposure, the endpoint selected 
for risk assessment is based on mydriasis observed in dogs. The 
additional 3x factor applied to chronic and other exposure scenarios is 
not applicable to acute exposure because steepness of the dose and 
severity of effects were not seen in the studies where mydriasis 
occurred. In addition, reduced body weight is not considered a single 
dose effect and would not be appropriate as a toxicity endpoint for 
acute exposure scenarios.
    v. There are no residual concerns with respect to the exposure 
databases. The chronic and acute dietary food exposure assessment 
utilizes reliable data on anticipated residues and percent crop treated 
as well as default processing factors. The dietary drinking water 
assessment utilized modeling results which included conservative 
assumptions for the parent and all degradates of concern. Conservative 
assumptions were used in the water models. Therefore, the water 
exposure assessment will not underestimate the potential risks for 
infants and children. Likewise, the use of maximum application rates 
and central-to-high end inputs results in calculated residential 
exposures that should not underestimate the risks to infants and 
children from these requested uses.

E. Aggregate Risks and Determination of Safety

    EPA determines whether acute and chronic pesticide exposures are 
safe by comparing aggregate exposure estimates to the acute population 
adjusted dose (aPAD) and chronic population adjusted dose (cPAD). The 
aPAD and cPAD represent the highest safe exposures, taking into account 
all appropriate SFs. EPA calculates the aPAD and cPAD by dividing the 
POD by all applicable UFs. For linear cancer risks, EPA calculates the 
probability of additional cancer cases 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 POD to ensure that the MOE called for by the product of 
all applicable UFs is not exceeded.
    1. Acute risk. The acute aggregate risk assessment takes into 
account exposure from dietary (food and water) consumption. Using the 
exposure assumptions discussed in this unit for acute exposure, the 
acute dietary exposure from food and water to avermectin B1 
and its delta-8,9-isomer will occupy 27% of the aPAD for children 1 to 
2 years old, the population group receiving the greatest exposure.
    2. Chronic risk. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that chronic exposure to 
avermectin B1 and its delta-8,9-isomer from food and water 
will utilize 47% of the cPAD for children 1 to 2 years old, the 
population group receiving the greatest exposure. Based on the 
explanation in Unit III.C.3., regarding residential use patterns, 
chronic residential exposure to residues of avermectin B1 
and its delta-8,9-isomer is not expected.
    3. Short- and intermediate-term risk. Short- and intermediate-term 
aggregate exposure takes into account short-term residential exposure 
plus chronic exposure to food and water (considered to be a background 
exposure level). High-end estimates of residential exposure were used, 
while average values were used for food and drinking water exposure. 
Avermectin B1 is currently registered for uses that could 
result in short- and intermediate-term residential exposure and the 
Agency has determined that it is appropriate to aggregate chronic 
exposure through food and water with short- and intermediate-term 
residential exposures to avermectin B1 and its delta-8,9-
isomer. Using the exposure assumptions described in this unit for 
short-term exposures, EPA has concluded the combined short- and 
intermediate-term food, water, and residential exposures result in 
aggregate MOEs of 500 for children 1 to 2 years old, the population 
group receiving the greatest exposure.
    4. Aggregate cancer risk for U.S. population. Based on the absence 
of a significant increase in tumor incidence in two rodent studies, EPA 
classified avermectin B1 as ``not likely to be carcinogenic 
to humans'' and it is, therefore, not expected to pose a cancer risk.
    5. 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 avermectin B1 and its delta-8,9-isomer residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methods for avermectin B1 in plant 
and livestock commodities are available in PAM II. The methods have 
been validated for citrus and processed fractions (Method I), ginned 
cottonseed (Method IA), and bovine tissues and milk (Method II). These 
methods determine residues in plant and livestock commodities at limits 
of quantitation of 0.02 ppm for meat and meat byproducts and <=0.01 ppm 
for other plant/livestock commodities. The limits of detection of the 
methods for plant and livestock commodities is 0.001 ppm for each 
analyte, equivalent to 0.002 ppm for two analyte peaks (i.e., 
avermectin B1a and its delta-8,9-isomer in one peak and 
avermectin B1b and its delta-8,9-isomer in the other peak).
    The plant methods used for data collection adequately measure the 
residues of concern. The methods have been validated at 0.001, 0.002, 
or 0.005 ppm (depending on the commodity and the method) for each of 
two analyte peaks (avermectin B1a and its delta-8,9-isomer 
in one peak and avermectin B1b and its delta-8,9-isomer in 
the other peak), which means that the LOQs of the data collection 
methods would be 0.002, 0.004 or 0.01 ppm.
    The 1990 Pestrak database indicates that avermectin B1 
and its metabolites are not recovered or not likely to be recovered by 
FDA multiresidue methods. Therefore, the multiresidue methods can not 
be used to determine residues for dietary exposure assessment and can 
not be used as the primary enforcement method.

B. International Residue Limits

    The Codex tolerance expressions for plants are consistent with the 
U.S. tolerance expression.

C. Response to Comments

    No comments were received to the Notices of Filing.

D. Revisions to Petitioned-For Tolerances

    The correct commodity definitions are obtained from the ``Food and 
Feed Commodity Vocabulary'', which can be found at http://www.epa.gov/
pesticides/foodfeed. Some proposed tolerance levels were raised based 
on EPA's analysis of the residue data, EPA's assessment of the limits 
of quantitation of the analytical methods, current livestock feed items 
(OPPTS Guideline 860.100, Table 1 Feedstuffs, June 2008), and/or to 
coordinate with Codex Maximum Residue Limits (MRLs).

V. Conclusion

    Therefore, tolerances are established for combined residues of 
avermectin B1 (a mixture of avermectins containing greater 
than or equal to 80% avermectin B1a (5-O-demethyl avermectin 
A1) and less than or equal to 20% avermectin B1b 
(5-O-demethyl-25-de (1-

[[Page 39551]]

methylpropyl)-25-(1-methylethyl) avermectin A1)), and its 
delta-8,9-isomer in/on cattle, fat at 0.03 ppm; cattle, meat byproducts 
at 0.06 ppm; fruit, stone, group 12 at 0.09 ppm; goat, fat at 0.01 ppm; 
hog, fat at 0.01 ppm; horse, fat at 0.01 ppm; nut, tree, group 14 at 
0.01 ppm; pistachio at 0.01 ppm; sheep, fat at 0.01 ppm; and vegetable, 
tuberous and corm subgroup 01C at 0.01 ppm.
    Existing tolerances for cattle, fat and cattle, meat byproducts are 
revised. Existing individual crop tolerances on almond, plum, potato, 
and walnut are deleted and replaced by the establishment of new crop 
group tolerances. Existing tolerances on almond, hulls and plum, prune, 
dried are retained. The expression for existing mint tolerances is 
corrected by deleting the term mint and replacing with peppermint, tops 
at 0.010 ppm and spearmint, tops at 0.010 ppm.

VI. Statutory and Executive Order Reviews

    This final rule establishes tolerances under section 408(d) of 
FFDCA 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 section 408(d) of FFDCA, 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 section 408(n)(4) of FFDCA. 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) (Public Law 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: July 28, 2009.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

0
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.  180.449, the table to paragraph (a) is amended by revising 
the entries for cattle, fat and cattle, meat byproducts; by removing 
the entries for almond, plum, mint, potato and walnut; and by adding 
alphabetically, the remaining entries in the table to read as follows:

180.449  Avermectin B1 and its delta-8,9-isomer; tolerances 
for residues.

    (a) * * *

------------------------------------------------------------------------
                                                               Parts per
                          Commodity                             million
------------------------------------------------------------------------
                                * * * * *
Cattle, fat..................................................       0.03
Cattle, meat byproducts......................................       0.06
                                * * * * *
Fruit, stone, group 12.......................................       0.09
Goat, fat....................................................       0.01
                                * * * * *
Hog, fat.....................................................       0.01
                                * * * * *
Horse, fat...................................................       0.01
                                * * * * *
Nut, tree, group 14..........................................       0.01
                                * * * * *
Peppermint, tops.............................................      0.010
Pistachio....................................................       0.01
                                * * * * *
Sheep, fat...................................................       0.01
                                * * * * *
Spearmint, tops..............................................      0.010
Vegetable, tuberous and corm, subgroup 01C...................       0.01
------------------------------------------------------------------------

* * * * *

[FR Doc. E9-19006 Filed 8-6-09; 8:45 am]

BILLING CODE 6560-50-S