Ethalfluralin; Notice of Filing a Pesticide Petition to Establish a Tolerance for a Certain Pesticide Chemical in or on Food, 51797-51802 [05-17124]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 70, Number 168 (Wednesday, August 31, 2005)]
[Notices]
[Pages 51797-51802]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-17124]


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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2005-0195; FRL-7730-4]


Ethalfluralin; Notice of Filing a Pesticide Petition to Establish 
a Tolerance for a Certain Pesticide Chemical in or on Food

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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

DATES: Comments, identified by docket identification (ID) number OPP-
2005-0195, must be received on or before September 30, 2005.

ADDRESSES: Comments may be submitted electronically, by mail, or 
through hand delivery/courier. Follow the detailed instructions as 
provided in Unit I. of the SUPPLEMENTARY INFORMATION.

FOR FURTHER INFORMATION CONTACT: Sidney Jackson, Registration Division 
(7505C), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 305-7610; e-mail address:jackson.sidney@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you an 
agricultural producer, food manufacturer, or pesticide manufacturer. 
Potentially affected entities may include, but are not limited to:
     Crop production (NAICS code 111)
     Animal production (NAICS code 112)
     Food manufacturing (NAICS code 311)
     Pesticide manufacturing (NAICS 32532)
    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in 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 Copies of this Document and Other Related Information?

    1. Docket. EPA has established an official public docket for this 
action under docket ID number OPP-2005-0195. The official public docket 
consists of the documents specifically referenced in this action, any 
public comments received, and other information related to this action. 
Although, a part of the official docket, the public docket does not 
include Confidential Business Information (CBI) or other information 
whose disclosure is restricted by statute. The official public docket 
is the collection of materials that is available for public viewing at 
the Public Information and Records Integrity Branch (PIRIB), Rm. 119, 
Crystal Mall 2, 1801 S. Bell St., Arlington, VA. This docket 
facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. The docket telephone number is (703) 305-
5805.
    2. Electronic access. You may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at https://www.epa.gov/fedrgstr/.
    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at https://www.epa.gov/edocket/ to submit or view public 
comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Although, not all docket materials may be 
available electronically, you may still access any of the publicly 
available docket materials through the docket facility identified in 
Unit I.B.1. Once in the system, select ``search,'' then key in the 
appropriate docket ID number.
    Certain types of information will not be placed in the EPA Dockets.

[[Page 51798]]

Information claimed as CBI and other information whose disclosure is 
restricted by statute, which is not included in the official public 
docket, will not be available for public viewing in EPA's electronic 
public docket. EPA's policy is that copyrighted material will not be 
placed in EPA's electronic public docket but will be available only in 
printed, paper form in the official public docket. To the extent 
feasible, publicly available docket materials will be made available in 
EPA's electronic public docket. When a document is selected from the 
index list in EPA Dockets, the system will identify whether the 
document is available for viewing in EPA's electronic public docket. 
Although, not all docket materials may be available electronically, you 
may still access any of the publicly available docket materials through 
the docket facility identified in Unit I.B. EPA intends to work towards 
providing electronic access to all of the publicly available docket 
materials through EPA's electronic public docket.
    For public commenters, it is important to note that EPA's policy is 
that public comments, whether submitted electronically or on paper, 
will be made available for public viewing in EPA's electronic public 
docket as EPA receives them and without change, unless the comment 
contains copyrighted material, CBI, or other information whose 
disclosure is restricted by statute. When EPA identifies a comment 
containing copyrighted material, EPA will provide a reference to that 
material in the version of the comment that is placed in EPA's 
electronic public docket. The entire printed comment, including the 
copyrighted material, will be available in the public docket.
    Public comments submitted on computer disks that are mailed or 
delivered to the docket will be transferred to EPA's electronic public 
docket. Public comments that are mailed or delivered to the docket will 
be scanned and placed in EPA's electronic public docket. Where 
practical, physical objects will be photographed, and the photograph 
will be placed in EPA's electronic public docket along with a brief 
description written by the docket staff.

C. How and to Whom Do I Submit Comments?

    You may submit comments electronically, by mail, or through hand 
delivery/courier. To ensure proper receipt by EPA, identify the 
appropriate docket ID number in the subject line on the first page of 
your comment. Please ensure that your comments are submitted within the 
specified comment period. Comments received after the close of the 
comment period will be marked ``late.'' EPA is not required to consider 
these late comments. If you wish to submit CBI or information that is 
otherwise protected by statute, please follow the instructions in Unit 
I.D. Do not use EPA Dockets or e-mail to submit CBI or information 
protected by statute.
    1. Electronically. If you submit an electronic comment as 
prescribed in this unit, EPA recommends that you include your name, 
mailing address, and an e-mail address or other contact information in 
the body of your comment. Also, include this contact information on the 
outside of any disk or CD ROM you submit, and in any cover letter 
accompanying the disk or CD ROM. This ensures that you can be 
identified as the submitter of the comment and allows EPA to contact 
you in case EPA cannot read your comment due to technical difficulties 
or needs further information on the substance of your comment. EPA's 
policy is that EPA will not edit your comment, and any identifying or 
contact information provided in the body of a comment will be included 
as part of the comment that is placed in the official public docket, 
and made available in EPA's electronic public docket. If EPA cannot 
read your comment due to technical difficulties and cannot contact you 
for clarification, EPA may not be able to consider your comment.
    i. EPA Dockets. Your use of EPA's electronic public docket to 
submit comments to EPA electronically is EPA's preferred method for 
receiving comments. Go directly to EPA Dockets at https://www.epa.gov/
edocket/, and follow the online instructions for submitting comments. 
Once in the system, select ``search,'' and then key in docket ID number 
OPP-2005-0195. The system is an ``anonymous access'' system, which 
means EPA will not know your identity, e-mail address, or other contact 
information unless you provide it in the body of your comment.
    ii. E-mail. Comments may be sent by e-mail to opp-docket@epa.gov, 
Attention: Docket ID number OPP-2005-0195. In contrast to EPA's 
electronic public docket, EPA's e-mail system is not an ``anonymous 
access'' system. If you send an e-mail comment directly to the docket 
without going through EPA's electronic public docket, EPA's e-mail 
system automatically captures your e-mail address. E-mail addresses 
that are automatically captured by EPA's e-mail system are included as 
part of the comment that is placed in the official public docket, and 
made available in EPA's electronic public docket.
    iii. Disk or CD ROM. You may submit comments on a disk or CD ROM 
that you mail to the mailing address identified in Unit I.C.2. These 
electronic submissions will be accepted in WordPerfect or ASCII file 
format. Avoid the use of special characters and any form of encryption.
    2. By mail. Send your comments to: Public Information and Records 
Integrity Branch (PIRIB) (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001, Attention: Docket ID number OPP-2005-0195.
    3. By hand delivery or courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Office of Pesticide 
Programs (OPP), Environmental Protection Agency, Rm. 119, Crystal Mall 
2, 1801 S. Bell St., Arlington, VA, Attention: Docket ID 
number OPP-2005-0195. Such deliveries are only accepted during the 
docket's normal hours of operation as identified in Unit I.B.1.

D. How Should I Submit CBI to the Agency?

    Do not submit information that you consider to be CBI 
electronically through EPA's electronic public docket or by e-mail. You 
may claim information that you submit to EPA as CBI by marking any part 
or all of that information as CBI (if you submit CBI on disk or CD ROM, 
mark the outside of the disk or CD ROM as CBI and then identify 
electronically within the disk or CD ROM the specific information that 
is CBI). Information so marked will not be disclosed except in 
accordance with procedures set forth in 40 CFR part 2.
    In addition to one complete version of the comment that includes 
any information claimed as CBI, a copy of the comment that does not 
contain the information claimed as CBI must be submitted for inclusion 
in the public docket and EPA's electronic public docket. If you submit 
the copy that does not contain CBI on disk or CD ROM, mark the outside 
of the disk or CD ROM clearly that it does not contain CBI. Information 
not marked as CBI will be included in the public docket and EPA's 
electronic public docket without prior notice. If you have any 
questions about CBI or the procedures for claiming CBI, please consult 
the person listed under FOR FURTHER INFORMATION CONTACT.

[[Page 51799]]

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

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

II. What Action is the Agency Taking?

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

List of Subjects

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

    Dated: August 19, 2005.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

Summary of Petition

    The petitioner's summary of the pesticide petition is printed below 
as required by FFDCA section 408(d)(3). The summary of the petition was 
prepared by Interregional Research Project Number 4 (IR-4), and 
represents the view of the petitioner. The petition summary announces 
the availability of a description of the analytical methods available 
to EPA for the detection and measurement of the pesticide chemical 
residues or an explanation of why no such method is needed.

 Interregional Research Project Number 4 (IR-4)

 PP 1E6326, PP 2E6360 and PP 2E6466

    EPA has received pesticide petitions 1E6326, 2E6360 and from the 
Interregional Research Project Number 4 (IR-4), P.O. Box 231, Rutgers 
University, New Brunswick, NJ 08903 proposing, pursuant to section 
408(d) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 
346a(d), to amend 40 CFR part 180, by establishing tolerances for 
residues of ethalfluralin in or on the raw agricultural commodities 
rapeseed, canola, crambe, and mustard seed at 0.05 parts per million 
(ppm), potato at 0.05 ppm, and dill, at 0.05 ppm. IR-4 submitted the 
petitions on behalf of the registrant, Dow AgroSciences LLC, who 
prepared this notice of filing. EPA has determined that the petitions 
contain data or information regarding the elements set forth in section 
408(d)(2) of the FFDCA; however, EPA has not fully evaluated the 
sufficiency of the submitted data at this time or whether the data 
support granting of the petition. Additional data may be needed before 
EPA rules on the petition.

A. Residue Chemistry

    1. Plant metabolism. Nature of residue studies with 14C-
ethalfluralin have demonstrated very low terminal residues and that 
ethalfluralin per se is the residue of concern in plants grown in soil 
treated with this compound and that there are no significant metabolic 
products. These studies indicate that it is appropriate to base a 
tolerance on residues of the parent compound, ethalfluralin.
    2. Analytical method--i. Rapeseed. A residue method has been 
developed and validated at a limit of quantitation (LOQ) of 0.02 [mu]g/
g for the determination of ethalfluralin in rapeseed seed which 
utilizes capillary gas chromatography with mass selective detection 
(GC/MSD). Validation data were generated using this method during the 
analysis of the canola seed field samples from the magnitude of residue 
studies.
    ii. Potato. The residue method used for determination of 
ethalfluralin in potato was based upon Analytical Method No. AM-AA-CA-
R025-AB-755, ``Determination of Ethalfluralin in Agricultural Crops and 
Soil; Determination of Ethalfluralin in Potato and Potato Processed 
Products.'' Analysis was by gas chromatography using an electron 
capture detector. The analytical method was determined to have an LOQ 
of 0.05 ppm and a limit of detection (LOD) of 0.016 ppm.
    iii. Canola. A residue method has been developed and validated at 
an LOQ of 0.02 [mu]g/g for the determination of ethalfluralin in canola 
seed which utilizes capillary gas chromatography with mass selective 
detection (GC/MSD). Validation data were generated using this method 
during the analysis of the canola seed field samples from the magnitude 
of residue studies.
    iv. Safflower. Adequate residue analytical methods are available 
for purposes of registration based upon the analytical method for 
sunflower. A GC method, Method I, with electron capture detection is 
listed in the Pesticide Analytical Manual (PAM, Vol. II, Section 
180.416) for tolerance enforcement. Method I is applicable for analysis 
of ethalfluralin residues in or on sunflower seed. The LOD is 0.01 ppm.
    v. Dill. Dill was analyzed by the method ``Determination of 
Ethalfluralin in Agricultural Crops and Soil, '' Residue Method Number 
AM-AA-CA-R025-AB-755, Lilly Research Laboratories, Greenfield, IN 
(currently Dow AgroSciences). The LOQ was 0.050 ppm by a gas 
chromatograph with a Ni63 electron capture detector(ECD). Method 
validation was performed both prior to and concurrently with sample 
analysis.
    3. Magnitude of residues--i. Canola. In the magnitude of residue 
field studies, herbicides containing the active ingredient 
ethalfluralin N-ethyl-N-(2-methyl-2-propenyl)-2,6-dinitro-4-
(trifluoromethyl) benzenamine were applied in 1996 at eight sites as a 
preplant incorporated application. Sonalan* 10G herbicide was applied 
directly to the soil surface and Sonalan* HFP herbicide was diluted in 
water and applied in a spray volume of 16-23 gallon/Acre (gal/A). The 
applications were made to field plots of canola at the rate of 1.25 lb 
active ingredient/Acre (a.i./A) at all sites except GA and WA, and at 
the rate of 0.75 lb a.i./A (GA and WA). Three to five days after 
application, a second incorporation was done and canola seeds were 
planted. Samples of canola seeds were collected at normal harvest, 87-
216 days after the last application. Residues in canola seed collected 
at normal harvest were non-detectable based on a method lower limit of 
detection of 0.004 ppm.
    ii. Potato. In the magnitude of residue field studies, 
ethalfluralin N-ethyl-N-(2-methyl-2-propenyl)-2,6-dinitro-4-
(trifluoromethyl) benzenamine was applied as a preemergence broadcast 
treatment at a nominal rate of 1.0 lb a.i./acre and was incorporated 
into the soil

[[Page 51800]]

with the use of sprinkler irrigation or a drag harrow. Samples of 
marketable potatoes were collected at normal harvest, 65-143 days after 
treatment application. No residues of ethalfluralin above the limit of 
detection were observed in the potato raw agricultural commodity (RAC) 
or processed fractions (chips, flakes, and wet peel).
    iii. Safflower. The magnitude of residue data from sunflower are 
surrogate data for safflower. The registered uses of ethalfluralin on 
sunflowers along with the established tolerances on these commodities 
are supported by acceptable field residue data from trials reflecting 
the maximum registered use patterns. In all cases, the residues were 
<0.01 ppm. The reregistration requirements for processing studies were 
fulfilled. Adequate processing studies have been conducted on sunflower 
seed. Field residue data resulting from up to 5X label rates showed 
non-detectable (<0.01 ppm) residues of ethalfluralin in sunflower seed.
    iv. Dill. In the magnitude of residue field studies, herbicides 
containing the active ingredient ethalfluralin N-ethyl-N-(2-methyl-2-
propenyl)-2,6-dinitro-4-(trifluoromethyl) benzenamine were applied in 
1997 at three sites. Ethalfluralin formulated as Curbit EC was applied 
directly to the soil surface, diluted in water and applied in a spray 
volume of 36 gal/A. The applications were made to field plots of canola 
at the rate of 1.5 lb a.i./A and incorporated by sprinkler irrigation. 
Samples of dill were collected at normal harvest, 91-100 days after the 
last application. Residues in fresh and dried dill collected at normal 
harvest were non-detectable based on a method lower limit of detection 
of 0.05 ppm.

B. Toxicological Profile

    1. Acute toxicity. Ethalfluralin is of relatively low toxicity. The 
rat oral lethal dose, LD50 is >10,000 mg/kg. The acute 
dermal LD50 in rabbits is >2,000 milligram/kilogram (mg/kg) 
and the acute rat inhalation lethal concentration LC50 is 
>0.94 mg/liter (L) air. Ethalfluralin produced slight eye irritation 
and slight dermal irritation in rabbits. A guinea pig dermal 
sensitization study conducted by the modified Buehler method found no 
sensitization, whereas a study conducted by the Magnusson and Kligman 
maximization method showed a positive sensitization reaction. The 
signal word for the technical grade active ingredient is ``Caution.''
    2. Genotoxicty. Ethalfluralin was weakly mutagenic in activated 
strains TA1535 and TA100 of salmonella typhimurium, but not in strains 
TA1537, TA1538, and TA98 in an Ames assay. In a modified Ames assay 
with salmonella typhimurium and e- coli, ethalfluralin was weakly 
mutagenic in strains TA1535 and TA100, with and without activation, and 
in strain TA98 without activation, at the highest dose. No mutagenicity 
was found in the mouse lymphoma assay for forward mutation. 
Ethalfluralin did not induce unscheduled DNA synthesis in rat 
hepatocytes. In Chinese hamster ovary cells, ethalfluralin was negative 
without S9 activation, but it was clastogenic with activation.
    3. Reproductive and developmental toxicity. The maternal no-
observed adverse effect level (NOAEL) of ethalfluralin in rats was 50 
mg/kg/day. The maternal lowest observed adverse effect level (LOAEL) 
was 250 mg/kg/day, based on decreased body weight gain and dark urine. 
In this rat study there was no observable developmental toxicity. The 
developmental NOAEL in rats was 1,000 mg/kg/day, the highest dose. In 
rabbits the NOAELs for maternal and developmental toxicity were 75 mg/
kg/day. The maternal LOAEL at 150 mg/kg/day was based on abortions and 
decreased food consumption. These effects as well as decreased weight 
gain, enlarged liver, and orange urine were found at 300 mg/kg/day. In 
this study developmental toxicity was observed. The developmental LOAEL 
in rabbits was 150 mg/kg/day, based on slightly increased resorptions, 
abnormal cranial development, and increased sternal variants. In a 
three-generation rat reproduction study, the parental NOAEL was 12.5 
mg/kg/day. The parental LOAEL was 37.5 mg/kg/day, based on depressed 
mean body weight gains in males in all generations. No treatment-
related effects were noted on reproductive parameters and the NOAEL was 
37.5 mg/kg/day or greater. A 7-month multigeneration bridging study was 
conducted with doses equivalent to 0, 8, 20, or 61 mg/kg/day in the 
diet of Fischer 344 rats. The parental NOAEL was 20 mg/kg/day. The 
parental LOAEL was 61 mg/kg/day based on increased liver weights. No 
treatment-related effects were noted on reproductive parameters and the 
reproductive NOAEL was equal to or greater than 61 mg/kg/day.
    4. Subchronic toxicity. Ethalfluralin was evaluated in five 
subchronic dietary studies which showed NOAELs of 560 ppm in a 3-month 
mouse study, 12 mg/kg/day in a 1-year mouse study, 29 mg/kg/day in a 3-
month rat study, 3.9 mg/kg/day in male rats and 4.9 mg/kg/day in female 
rats in a 1-year study, and 27.5 mg/kg/day in a 3-month dog study. A 
21-day dermal study in rabbits showed no systemic toxicity, while 
slight to severe dermal irritation was observed.
    5. Chronic toxicity. Ethalfluralin was administered to Fisher 344 
rats in the diet for 2 years in combined chronic toxicity and 
carcinogenicity replicate studies. The doses were equivalent to 0, 4.2, 
10.7, or 32.3 mg/kg/day. The NOAEL for systemic effects was 32.3 mg/kg/
day. Mammary gland fibroadenomas were found in dosed female rats at 
statistically significant incidences in the mid and high doses. 
Ethalfluralin was administered to B6C3F1 mice in the diet for 2 years 
in combined chronic toxicity and carcinogenicity replicate studies. The 
doses were equivalent to 0, 10.3, 41.9, or 163.3 mg/kg/day. No 
increased incidence of neoplasms was attributed to the treatment. The 
NOAEL was 10.3 mg/kg/day. The mid-dose (LOAEL) and high-dose showed 
focal hepatocellular hyperplasia in both sexes. There were increased 
relative liver, kidney, and heart weights in females. Some blood 
changes were found also, including decreased hematocrit, hemoglobin, 
and erythrocyte count accompanied by increased mean corpuscular 
hemoglobin concentration in high dose females. Alkaline phosphatase 
values were increased at the high dose in both sexes. Body weight gain 
decreased at the high dose.
    Beagle dogs were given 0, 4, 20, or 80 mg/kg/day orally, by 
capsule, for 1 year. The NOAEL was 4 mg/kg/day. The LOAEL was 20 mg/kg/
day, based on increased urinary bilirubin, variations in erythrocyte 
morphology, increased thrombocyte count, and increased erythroid series 
of the bone marrow. Elevated alkaline phosphatase levels were found at 
the two higher doses and siderosis of the liver at the high dose.
    EPA's Office of Pesticide Program's Carcinogenicity Peer Review 
Committee concluded that, ethalfluralin should be classified as Group 
C, a possible human carcinogen, based on increased mammary gland 
fibroadenomas and adenomas/fibroadenomas combined in female rats. The 
tumor incidences were statistically significant at both the mid and 
high dose, and exceeded the upper range of historical controls. Based 
on a low dose extrapolation, the Q1* of 8.9 x 10-2 (mg/kg/
day)-1 has been calculated.
    6. Animal metabolism. Fischer 344 rats were treated orally with a 
single low dose, a single high dose, or repeated low doses of 
radiolabeled ethalfluralin. Absorption of ethalfluralin was estimated 
at 79% - 87% of the dose for all dose levels. Ethalfluralin was rapidly

[[Page 51801]]

and extensively metabolized, and 95% of the chemical was excreted in 
urine and feces by 7 days. The major route of elimination for the 
radiolabel was in the feces, 50.9% - 63.2%, and the levels remaining in 
the tissues after 72 hours were negligible. The major metabolites in 
urine and feces were identified.
    7. Metabolite toxicology. The residue of concern is ethalfluralin 
per se, as specified in 40 CFR 180.416. Thus, there is no need to 
address metabolite toxicity.
    8. Endocrine disruption. There is no evidence to suggest that 
ethalfluralin has an effect on any endocrine system.

C. Aggregate Exposure

    1. Dietary exposure. Acute dietary risk assessments are performed 
for a food-use pesticide if a toxicological study has indicated the 
possibility of an acute effect of concern occurring as a result of a 1-
day or single exposure. EPA has previously used a NOAEL of 75 mg/kg/day 
from a rabbit developmental toxicity study as the toxicity endpoint for 
assessing acute dietary risk in females 13-50 years of age. An acute 
reference dose (aRfD) of 0.75 mg/kg/day was calculated, based on a 
NOAEL of 75 mg/kg/day and an uncertainty factor of 100 (10 for 
interspecies extrapolation and 10 for intraspecies variation). EPA has 
previously added a 3X FQPA safety factor, resulting in an acute 
popution adjusted dose (aPAD) of 0.25 mg/kg/day. Likewise, in this 
assessment acute dietary risk to females 13-50 years old was based on 
an aPAD of 0.25 mg/kg/day.
    Chronic dietary exposure to ethalfluralin is possible due to the 
potential presence of ethalfluralin residue in certain foods. Chronic 
dietary risk was evaluated using a chronic RfD of 0.04 mg/kg/day, which 
is based on a NOAEL of 4 mg/kg/day from a chronic dog study along with 
an uncertainty factor of 100. EPA previously concluded that an FQPA 
Safety Factor of 1X is appropriate for assessing chronic dietary risk.
    EPA has concluded, that ethalfluralin should be classified as group 
C, a possible human carcinogen, based on increased mammary gland 
fibroadenomas and adenomas/fibroadenomas combined in female rats. 
Therefore, a cancer risk assessment was included. Based on a low dose 
extrapolation, the Q1* of 8.9 x 10-2 (mg/kg/
day)-1 has been calculated and was used in this cancer risk 
assessment.
    i. Food. The dietary exposure assessment was based on all 
commodities with tolerances for ethalfluralin established at 40 CFR 
180.416 together with the proposed tolerances of 0.05 ppm for rapeseed, 
0.05 ppm for potatoes, and 0.05 ppm for dill, canola and safflower. The 
Dietary Exposure Evaluation Model (DEEMTM), which is 
produced by Novigen Sciences, Inc. and licensed to Dow AgroSciences, 
was used to estimate dietary exposure. This software used the food 
consumption data for the 1989-1991 USDA Continuing Surveys of Food 
Intake by Individuals (CSFII 1989-1991).
    a. Acute. An acute dietary risk assessment was conducted with the 
conservative assumptions of 100% crop treated and tolerance level 
residues for all crops. These assumptions result in a very conservative 
estimate of human exposure and risk. Acute dietary risk for females 13+ 
years old was assessed using an acute population adjusted dose (aPAD) 
of 0.25 mg/kg/day. Even with conservative assumptions used in this 
analysis acute dietary exposure was estimated to occupy only 0.05% of 
the aPAD for females 13+ years old. Adverse effects are not expected 
for exposures occupying 100% or less of the aPAD. Therefore, acute 
exposure and risk from food is well within acceptable levels.
    b. Chronic. Chronic dietary exposure and risk was estimated with 
the conservative assumptions of 100% crop treated and tolerance level 
residues for all crops. The estimate of potential chronic exposure and 
risk is very conservative and estimated risk would be substantially 
reduced with further refinement to the exposure estimate. Even with the 
conservative assumptions used in this analysis, chronic exposure is 
estimated to occupy only 0.2% of the RfD for the general U.S. 
population. Chronic dietary exposure is estimated to occupy 0.4% of the 
RfD for non-nursing infants, the population subgroup estimated to have 
highest potential exposure. Therefore, chronic exposure and risk from 
food is well within acceptable levels.
    c. Cancer. Cancer risk was estimated based on percent crop treated 
and anticipated residues (AR) as provided in EPA's Reregistration 
Eligibility Decision (RED) for ethalfluralin and EPA's final rule 
concerning tolerances for residue of ethalfluralin in or on canola seed 
and safflower seed (67 FR 2333, January 17, 2002). Since ethalfluralin 
residue in potatoes was below the LOD, a residue of 
1/89/21/13/23/85/83/8 the LOD or 0.008 ppm was assigned to 
potatoes for use in cancer risk assessment. Additionally, this dietary 
risk assessment was based on 40% of the U.S. potato crop being treated 
with ethalfluralin. Based on both registered and proposed product uses, 
exposure to ethalfluralin from food is estimated to not exceed a 
lifetime cancer risk of 8.47 x 10-7. Cancer risks of less 
than 1 x 10-6 are generally considered to be negligible.
    ii. Drinking water. There are no established maximum contaminant 
levels (MCLs) for residues of ethalfluralin in drinking water and 
health advisory levels (HALs) for ethalfluralin have not been 
established. EPA has previously used modeling for a screening level 
assessment of potential ethalfluralin exposure through drinking water. 
The Agency has used EPA's pesticide Root Zone Model/Exposure Analysis 
Modeling System (PRZM/EXAMS) and screening concentration in ground 
water (SCI-GRO) to provide a screening level assessment for surface 
water and ground water, respectively. Based on these models EPA has 
indicated the estimated environmental concentrations (EECs) for acute 
exposures are 2.3 parts per billion (ppb) for surface water and 0.02 
ppb for ground water. The EECs for chronic exposures are estimated to 
be 0.052 ppb for surface water and 0.02 ppb for ground water. Estimated 
concentrations of a pesticide are compared to a Drinking Water level of 
Comparison (DWLOC) as a surrogate estimate of exposure and risk. The 
DWLOC is the concentration of a pesticide in drinking water that would 
be acceptable as an upper limit in light of total aggregate exposure to 
that pesticide.
    a. Acute. As indicated previously, EPA has used surface water and 
ground water EECs of 2.3 ppb and 0.02 ppb, respectively, for comparison 
with the DWLOC in an acute assessment. The DWLOC for acute exposure in 
females 13+ years old was based on an aPAD of 0.25 mg/kg/day and was 
calculated to be 7,500 ppb. Therefore, the acute DWLOC for 
ethalfluralin is over 3,000 fold greater than the EEC for surface water 
or ground water, indicating that potential acute exposure and risk from 
drinking water is well within acceptable levels.
    b. Chronic. As indicated previously, EPA has used surface water and 
ground water EECs of 0.052 ppb and 0.02 ppb, respectively, for 
comparison with the DWLOC in a chronic assessment. The chronic DWLOC 
was calculated based on a chronic RfD of 0.04 mg/kg/day and accounted 
for potential chronic exposure to ethalfluralin through residues in 
food. The chronic DWLOC for the general U.S. population and non-nursing 
infants was calculated to be 1,400 ppb and 400 ppb, respectively. 
Therefore, chronic DWLOCs are substantially greater than estimated 
residue concentration in surface water or ground water over a chronic 
exposure period, indicating that chronic exposure

[[Page 51802]]

and risk from drinking water are well within acceptable levels.
    c. Cancer. The DWLOC for the cancer risk assessment was calculated 
to be 0.12 ppb. Surface water and ground water EECs of 0.052 ppb and 
0.02 ppb, respectively, were used for comparison with the DWLOC. The 
EECs are below the DWLOC, indicating that the cancer risk would 
generally be considered negligible.
    2. Non-dietary exposure. Ethalfluralin is not currently registered 
for use on any residential non-food sites, and thus, it is not expected 
that non-occupational, non-dietary exposures will occur.

D. Cumulative Effects

    EPA at this time has not established methodologies to resolve the 
complex issues concerning common mechanism of toxicity in a meaningful 
way. Although, ethalfluralin is a member of the dinitroaniline class of 
herbicides, there is no information available at this time to determine 
whether ethalfluralin has a common mechanism of toxicity with other 
substances or how to include this pesticide in a cumulative risk 
assessment. Based on the metabolic profile, the registrant concludes 
that ethalfluralin does not appear to produce a toxic metabolite 
produced by other substances. Therefore, only aggregate exposure and 
risk were considered.

E. Safety Determination

    1. U.S. population. Using conservative exposure assumptions 
previously described, chronic dietary exposure to residues of 
ethalfluralin from current and proposed uses was estimated to occupy 
only 0.2% of the RfD for the general U.S. population. EPA generally has 
no concern for exposures below 100% of the RfD since the RfD represents 
the level at or below which daily exposure over a lifetime will not 
pose appreciable risks to human health. Additionally, the chronic DWLOC 
was found to be substantially greater than EECs for ethalfluralin in 
surface water or ground water, indicating risk is well within 
acceptable levels. Cancer risk resulting from potential exposure to 
ethalfluralin through food and drinking water was estimated. Cancer 
risk from potential dietary and drinking water exposure for the general 
U.S. population was found to be within a range that EPA has generally 
considered negligible. Thus, based on the completeness and reliability 
of the toxicity data and the conservative exposure assessment, it is 
concluded that, there is a reasonable certainty that no harm will 
result to the general U.S. population from aggregate exposure to 
ethalfluralin residues from current and proposed uses.
    2. Infants and children. Risk for developmental toxicity from acute 
exposure to ethalfluralin was evaluated for females 13+ years old. As 
indicated in the previous discussion, risk from aggregate acute 
exposure to ethalfluralin through food and drinking water is well 
within acceptable levels. It can be concluded that there is a 
reasonable certainty that no harm will result for both females 13+ 
years old and for the pre-natal development of infants from aggregate 
acute exposure to ethalfluralin.
    Chronic aggregate exposure and risk was evaluated for non-nursing 
infants, the population subgroup predicted to be most highly exposed. 
As indicated previously, risk from aggregate chronic exposure through 
food and drinking water is well within acceptable levels. Thus, based 
on the completeness and reliability of the toxicity data and the 
conservative exposure assessment, it can be concluded with reasonable 
certainty that no harm will result to infants and children from chronic 
aggregate exposure to ethalfluralin based on current and proposed uses.

F. International Tolerances

    There are no Codex, Canadian or Mexican maximum residue limits 
established for ethalfluralin.

[FR Doc. 05-17124 Filed 8-30-05; 8:45 am]
BILLING CODE 6560-50-S