[Federal Register Volume 69, Number 240 (Wednesday, December 15, 2004)]
[Notices]
[Pages 75066-75070]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-27173]



[[Page 75066]]

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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2004-0378; FRL-7688-2]


2,4-D; Notice of Filing a Pesticide Petition to Establish a 
Permanent 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 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-
2004-0378, must be received on or before January 14, 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: Joanne I. Miller, Registration 
Division (7505C), Office of Pesticide Programs, EnvironmentalProtection 
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; 
telephone number: (703) 305-6224; e-mail 
address:[email protected].

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 111)
     Animal production (NAICS 112)
     Food manufacturing (NAICS 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-2004-0378. 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 http://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 http://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. 
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 in 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

[[Page 75067]]

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 totechnical 
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 http://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-2004-0378. 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 [email protected], 
Attention: Docket ID Number OPP-2004-0378. 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-2004-0378.
    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-2004-0378. 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.

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: November 30, 2004.
Lois Rossi,
Director, Registration Division, Office of Pesticide Programs.

Summary of Petition

     The petitioner summary of the pesticide petition is printed below 
as required by FFDCA section 408(d)(3). The summary of the petition was 
prepared by the petitioner 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

PP 4E3060

    EPA has received a pesticide petition (4E3060) from the Industry 
Task Force II on 2,4-D Research Data (Task Force) and its registrant 
members and affiliates, 1900 K St., NW., Washington, DC 20006 on behalf 
of The Interregional Research Project Number 4 (IR-4) 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 to remove the 
expiration date of December 31, 2004 for 2,4-D in or on the raw 
agricultural commodity soybean seed at 0.02 parts per million (ppm) (40 
CFR 180.142(a)(11)) (March 8, 2002, 67 FR 10622). EPA has determined 
that the petition contains data or information

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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 and animal metabolism. The nature of the residue in plants 
is adequately understood. Acceptable wheat, lemon, and potato 
metabolism studies have been submitted. The nature of the residue in 
animals is adequately understood based upon acceptable ruminant and 
poultry metabolism studies submitted.
    2. Analytical method. The residue field tests on soybeans used a 
gas chromatography (GC) method with electron capture detection (ECD), 
EN-CAS method ENC-2/93. This GC/ECD method is adequate for determining 
residues in or on soybeans with a limit of quantitation (LOQ) of 0.01 
part per million (ppm).
    3. Magnitude of residues. In 27 tests on soybeans conducted in 
Arkansas, Illinois, Louisiana, Missouri, and Tennessee, residues of 
2,4-D were nondetectable (<0.01 ppm) in/on all samples of forage, and 
seeds from soybeans treated with a preplant application of 2,4-D (acid, 
ester, or amine) at 0.5, 1.25, and 2.75 lbs active ingredient per acre 
at lX, 2.5X, and 5.5X rates. Residues of 2,4-D were also nondetectable 
(<0.01 ppm) in/on 21 of 27 hay samples from the same tests. Hay samples 
with detectable residues of 0.01-0.04 ppm only came from 2.5X and 5.5X 
applications of the 2,4-D 2-ethylhexyl ester (2-EHE). Since data from 
the 5.5X application demonstrate that 2,4-D residues on soybean seeds 
are nondetectable or <0.05 ppm, a soybean processing study is not 
required. Based on the residue data for soybeans, tolerances of 0.02, 
2.0, and 0.02 ppm in or on the raw agricultural commodities soybean 
seed, hay, and forage are appropriate.

B. Toxicological Profile

    1. Acute toxicity. The oral lethal dose (LD)50 of 2,4-D 
acid is 699 milligrams/kilogram (mg/kg) in the rat. The dermal 
LD50 in the rabbit is >2,000 mg/kg. The acute inhalation 
lethal concentration (LC)50 in the rat is >1.8 milligrams/
liter (mg/l). A primary eye irritation study in the rabbit showed 
severe irritation. A dermal irritation study in the rabbit showed 
moderate irritation. A dermal sensitization study in the guinea pig 
showed no skin sensitization. An acute neurotoxicity study in the rat 
produced a no observed adverse effect level (NOAEL) of 227 mg/kg for 
systemic toxicity and a neurobehavioral NOAEL of 67 mg/kgwith a lowest 
observed adverse effect level (LOAEL) of 227 mg/kg.
    2. Genotoxicty. Mutagenicity studies including gene mutation, 
chromosomal aberrations, and direct DNA damage tests were negative for 
mutagenic effects. 2,4-D acid has been evaluated extensively in open 
literature in a range of in vivo and in vitro assays that have included 
tests with human cells. Overall, the pattern of responses observed in 
both in vivo and in vitro tests indicates that 2,4-D acid was not 
mutagenic, although some cytogenetic effects were observed.
    3. Reproductive and developmental toxicity. A two-generation 
reproduction study was conducted in rats with NOAELs for parental and 
offspring toxicity of 5 milligrams/kilograms/day (mg/kg/day). The 
LOAELs for this study are established at 20 mg/kg/day based on 
decreased female body weight/body weight gain (F1), male renal tubule 
alteration (F0 and F1), and decreased pup body weight (F1b). A 
teratology study in rabbits given gavage doses at 0, 10, 30, and 90 mg/
kg on days 6 through 18 of gestation was negative for developmental 
toxicity at alldoses tested. A teratology study in rats given gavage 
doses at 0, 8, 25, and 75 mg/kg on days 6 through 15 of gestation 
showed maternal toxicity only at 75 mg/kg, which is above the renal 
clearance threshold for 2,4-D. A NOAEL for fetotoxicity was established 
at 25 mg/kg/day based on skeletal abnormalities and variations at the 
75 mg/kg dose level. The effects on pups occurred in the presence of 
parental toxicity.
    4. Subchronic toxicity. A subchronic dietary study was conducted 
with mice fed diets containing 0, 1, 15, 100, and 300 mg/kg/day with a 
NOAEL of 15 mg/kg/day. The LOAEL was established at 100 mg/kg/day based 
on decreased glucose and thyroxine levels, increases in absolute and 
relative kidney weights, and histopathological lesions in the liver and 
kidneys. A 90-day dietary study in rats fed diets containing 0, 1, 15, 
100, or 300 mg/ kg/day resulted in a NOAEL of 15 mg/kg/day, and an 
LOAEL of 100 mg/kg/day. The LOAEL was based on decreases in body weight 
and food consumption, alteration in clinical pathology, changes in 
organ weights, and histopathological lesions in the kidney, liver, and 
adrenal glands of both sexes of rats. A 90-day feeding study was 
conducted in dogs fed diets containing 0, 0.3, 1, 3, and 10 mg/kg/day 
with a NOAEL of 1 mg/kg/day. The LOAEL was established at 3 mg/kg/day 
based on decreased body weight/body weight gain and food consumption 
(males), alterations in clinical chemistry parameters increased blood 
urea nitrogren (both sexes), creatinine (both sexes), and decreased 
testis weight (males).
    5. Chronic toxicity. Previously, the 2,4-D chronic reference dose 
was based on the chronic dog study. More recently, the Hazard 
Identification Assessment Review Committee (HIARC) chose to use the rat 
as the more relevant species for risk assessment. Use of the dog as the 
basis for regulation exaggerates the apparent severity of effects 
anticipated because of the limited renal capacity of dogs to excrete 
organic acids. Points of consideration included: The dog has a 
decreased clearance relative to humans, rats, mice, and other species. 
The decreased clearance results in higher blood levels in the dog 
relative to those found in the rat and consequently, effects are seen 
at lower dose levels in the dog than in the rat. The half-life of 
elimination for dogs is significantly longer than for all other species 
considered. Dogs exhibited half-lives of 31 to 106 hours for doses of 1 
to 5 mg/kg. In other species (mice, rats, pigs, cats, and humans), 
elimination half-lives ranged from 0.75 to 11.6 hours for similar 
doses. The difference in the elimination pattern among dogs and other 
mammalian species persuaded HIARC that the rat was a better predictor 
than the dog of the potential toxicity of 2,4-D to human.
    A 2-year oncogenicity study was conducted in mice fed diets 
containing 0, 1, 15, and 45 mg/kg/day with a NOAEL of 1 mg/kg/day. The 
systemic LOAEL was established at 15 mg/kg/day based on treatment-
related increase in kidney weights in both sexes and microscopic renal 
lesions in males. There was no treatment-related increase in the 
incidence of any tumor type. A subsequent 2-year oncogenicity study in 
mice with a NOAEL of 5 mg/kg/day demonstrated that the NOAEL of 1 mg/
kg/day in this earlier study was an artifact of dose selection.
    A second 2-year oncogenicity study was conducted in mice fed diets 
containing 0, 5, 62.5, and 125 mg/kg/day (males) and 0, 5, 150, and 300 
mg/kg/day (females). The NOAEL was 5 mg/kg/day and LOAEL was 62.5 
(males) and 150 (females) mg/kg/day based on an increased absolute and/
or relative kidney weights and an increased incidence of renal 
microscopic lesions. There was no treatment-related increase in the 
incidence of any tumor type.
    A 2-year feeding/oncogenicity study was conducted in rats fed diets 
containing 0, 5, 75, and 150 mg/kg/day.

[[Page 75069]]

 The NOAEL was 5 mg/kg/day and the LOAEL was 75 mg/kg/day based on 
decreased body weight gain (females) and food consumption (females), 
alterations in hematology decreased red blood cells (females), 
hemoglobin (females), platelets (both sexes) and clinical chemistry 
parameters increased creatinine (both sexes), alanine and aspartate 
aminotransferase (males), alkaline phosphatase (both sexes), decreased 
T4 (both sexes), glucose (females), cholesterol (both sexes), and 
triglycerides (females), increased thyroid weights (both sexes at study 
termination), decreased testes and ovarian weights, and microscopic 
lesions in the lungs (females). At the high-dose level, there were 
microscopic lesions in the eyes, liver, adipose tissue, and lungs. 
There was no treatment-related increase in the incidence of any tumor.
    6. Animal metabolism. The metabolism of phenyl ring labeled 14C-
2,4-D was studied in the rat following a single intravenous or oral 
dose of approximately 1 mg/kg/day. At 48 hours after treatment, 
recovery of radioactivity in urine was in excess of 94%. Parent 2,4-D 
was the major metabolite (72.9% to 90.5%) found in the urine.
    7. Metabolite toxicology. Because 2,4-D is rapidly excreted without 
significant metabolism, the toxicology data on the parent compound 
adequately represents metabolite toxicology.
    8. Endocrine disruption. Although tests explicitly designed to 
evaluate the potential endocrine effects of 2,4-D have not been 
conducted, large and diverse batteries of toxicology studies are 
available including acute, subchronic, chronic, reproductive, and 
developmental toxicity tests. The thyroid effects seen in the 
subchronic (decreases in T4, follicular cell hypertrophy) and chronic 
(decreases in T4, increase in thyroid weights) toxicity study in rats 
occurred only at high doses, which were at or above the threshold of 
renal clearance. These effects were seen in the presence of other 
systemic (liver or kidney) toxicity, and there was no evidence of 
thyroid toxicity in dogs. No evidence of endocrine disruptions were 
seen in the appropriate parameters that evaluated this effect in the 
two-generation reproduction study.

C. Aggregate Exposure

    1. Dietary exposure. Residues are below the limit of quantification 
(LOQ = 0.01 ppm) in soybeans. Tolerances have been established (40 CFR 
180.142) for residues of 2,4-D as the acid or various of its salts and 
esters, in or on a variety of raw agricultural commodities. In 
addition, there are also tolerances for 2,4-D for meat, milk, and eggs.
    i. Food. The Agency has conducted an extensive assessment of the 
aggregate exposure. Results are reported in the Federal Register of 
March 8, 2002 (FR 67 10622) (FRL-6827-1). The Agency found that acute 
dietary exposure from food to 2,4-D will occupy 7.3% of the acute 
population adjusted dose (aPAD) for the U.S. population, 12% of the 
aPAD for females 13 years and older, 9.4% of the aPAD for infants less 
than 1 year old, 12% of the aPAD for children 1-6 years old, and 8.8% 
of the aPAD for children 7-12 years old. The Agency found that chronic 
dietary exposure to 2,4-D from food will utilize24% of the chronic 
population adjusted dose (cPAD) for the U.S. population, 20% for 
females 13 years and older, 19% of the cPAD for infants less than 1 
year old, 46% of the cPAD for children 1-6 years old, and 36% of the 
cPAD for children 7-12 years old.
    ii. Drinking water. 2,4-D is soluble in water. The average field 
half-life is 10 days. The chemical is potentially mobile, but rapid 
degradation in soil and removal by plant uptake minimizes leaching. A 
Maximum Contaminant Level (MCL) of 0.07 mg/L has been established. In 
addition, the following health advisories have been established: For a 
10-kg child, a range of 1 mg/L from 1-day exposure to 0.1 mg/L for 
longer-term exposure up to 7 years; for a 70 kg adult, a range of 0.4 
mg/L for longer-term exposure to 0.07 mg/L for lifetime exposure.
    2. Non-dietary exposure. 2,4-D is currently registered for use on 
the following residential non-food sites: Ornamental turf, lawns, and 
grasses, golf course turf, recreational areas, and several other 
indoor, and outdoor uses. 2,4-D is a commonly-used pesticide in non-
agricultural settings. There are chemical-specific and site-specific 
data available to determine the potential risks associated with 
residential exposures from the registered uses of 2,4-D. Dislodgeable 
residues taken from 10 2,4-D turf transferable residue studies showed 
low dislodgeable percent of application, 0.9% at 1 hour, 0.8% at 8 
hours, and 0.7% at 24 hours following applications. No detectable 
residues were found in urine samples supplied by volunteers exposed to 
sprayed turf 24 hours following application. Intermediate-term post-
application exposure is thus not expected.

D. Cumulative Effects

    A cumulative risk assessment cannot be performed as part of a human 
health risk assessment because EPA has not yet made a determination as 
to which compounds to which humans may be exposed, if any, have a 
common mechanism of toxicity. There are no available data to determine 
whether 2,4-D has a common mechanism of toxicity with other substances 
or how to include this pesticide in a cumulative risk assessment. 
Unlike other pesticides for which EPA has followed a cumulative risk 
approach based on a common mechanism of toxicity, 2,4-D does not appear 
to produce a toxic metabolite produced by other substances.

E. Safety Determination

    1. U.S. population. For chronic dietary exposure, EPA has 
established the RfD for 2,4-D at 0.005 mg/kg/day. This RfD is based on 
a 2-year dietary toxicity study in rats with a NOAEL of 5 mg/kg/day and 
an uncertainty factor of 1,000. In the most recent revised HED human 
health risk assessment, EPA used tolerance-level exposure values for 
most commodities, and averages of field trial data, and processing 
study factors for small grains, citrus, and sugarcane sugar, and 
molasses. EPA concluded that for food consumption only, chronic dietary 
(food only) risks calculated using the Dietary Exposure Evaluation 
Model (DEEMTM) software consumed 2.5-6.9% of the cPAD (2.5-
6.7% cPAD using Lifeline). Risk to the general U.S. population was 3.4% 
of the cPAD (3.2% cPAD using Lifeline). Despite the potential for 
exposure to 2,4-D in drinking water and from non-dietary, non-
occupational exposure, EPA did not expect the aggregate exposure to 
exceed 100% of the cPAD.
    For acute dietary exposure, the NOAEL of 67 mg/kg/day from the rat 
acute neurotoxicity study should be used for risk assessment. As 
neurotoxicity is the effect of concern, the acute dietary risk 
assessment should evaluate acute dietary risk to all population 
subgroups. Again, relying upon the June 2, 2004, revised HED human 
health risk assessment, EPA concluded that risk to the general U.S. 
population was 17% of the aPAD using both DEEMTM and 
Lifeline.
    Regarding dietary cancer risk assessment, EPA's Cancer Peer Review 
Committee has classified 2,4-D as a Group D chemical (not classifiable 
as to human carcinogenicity) on the basis that, the evidence is 
inadequate and cannot be interpreted as showing either the presence or 
absence of a carcinogenic effect.
    2. Infants and children. The database on 2,4-D relative to prenatal 
and postnatal toxicity is complete with respect to current data 
requirements. In its most recent evaluations, EPA has

[[Page 75070]]

determined that, based on the 2,4-D database summarized above, no 
special FQPA safety factor is needed (1X) since there are no residual 
uncertainties for prenatal and/or postnatal toxicity. Chronic dietary 
risk to children 1-2 years of age, the most highly exposed population 
subgroup, was 6.9% of the cPAD (6.7% cPAD using Lifeline). For acute 
dietary risk, the most highly exposed population subgroup using both 
DEEMTM and Lifeline was children 1-2 years of age; risks 
were 33% and 30% of the aPAD, respectively.

F. International Tolerances

    There are no Codex, Canadian, or Mexican maximum residue 
limitsestablished for 2,4-D on soybeans.

[FR Doc. 04-27173 Filed 12-14-04; 8:45 am]
BILLING CODE 6560-50-S