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Penoxsulam [Dow AgroSciences]. August 6, 2003. Pesticide tolerance petition. Federal Register.

Docket ID number OPP-2003-0261


http://www.epa.gov/fedrgstr/EPA-PEST/2003/August/Day-06/p20015.htm


[Federal Register: August 6, 2003 (Volume 68, Number 151)]
[Notices]
[Page 46609-46613]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr06au03-79]

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ENVIRONMENTAL PROTECTION AGENCY
[OPP-2003-0261; FRL-7320-4]

Penoxsulam; 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 ID number OPP-2003-0261, must be
received on or before September 5, 2003.

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 Miller, Registration Division
(7505C), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone
number: (703) 305-6224; e-mail address: miller.joanne@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:
    ¥ Crop production (NAICS 111)
    ¥ Animal production (NAICS 113)
    ¥ 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 identification (ID) number OPP-2003-0261. 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,
1921 Jefferson Davis Hwy., 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

[[Page 46610]]

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 EPA's 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 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 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-2003-0261. 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-2003-0261. 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-2003-0261.
    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, 1921 Jefferson Davis Hwy., Arlington, VA, Attention: Docket
ID Number OPP-2003-0261. 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

[[Page 46611]]

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 contain 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: July 28, 2003.
Debra Edwards,
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 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.

Dow AgroSciences LLC

PP 3F6542

    EPA has received a pesticide petition (3F6542) from Dow
AgroSciences LLC, 9330 Zionsville Road, Indianapolis, IN 46268
proposing, pursuant to section 408(d) of the FFDCA, 21 U.S.C. 346a(d),
to amend 40 CFR part 180, by establishing a tolerance for residues of
2-(2,2-difluoroethoxy)-6-trifluoromethyl-N-(5,8-dimethoxy
[1,2,4]triazolo-1,5c pyrimidin-2-yl) benzenesulfonamide, (penoxsulam,
DE-638) in or on the raw agricultural commodity rice raw agricultural
commodities (RACS) and rice processed products at 0.01 part per million
(ppm) for rice grain, 0.05 ppm for rice straw, 0.01 ppm for rice hull,
0.01 ppm for rice bran, and 0.01 ppm for polished rice. EPA has
determined that the petition contains 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. The nature of residue study in rice, treated
with \14\C-labeled DE-638 (2-position on the triazolopyrimidine ring or
uniformly labeled in the phenyl ring) at 100 grams (g/ha), demonstrated
that no significant residues (0.003-0.022 ppm) were found in mature
straw and grain. The residues were fractionated by reversed-phase high
performance liquid chromotography (HPLC) and consisted of DE-638, 5-OH
DE-638 (identified by retention time), and two unidentified peaks. Each
component was <0.01 [mu]g/g (DE-638 equivalents). Based on the plant
metabolism studies, the tolerance expression is the parent, penoxulam.
    Metabolism studies in livestock animals with \14\C-labeled DE-638
(2-position on the triazolopyrimidine ring or uniformly labeled in the
phenyl ring) at a concentration equivalent to about 10 ppm in the diet
indicated that approximately 99% of the administered dose was
eliminated in the excreta. The low levels of residues (0.002-0.07 ppm)
in fat and edible tissues, milk or eggs demonstrate that residues due
to DE-638 would not accumulate in the animals. Additionally, the dose
levels in these studies are about 200 to 1,000 times higher than the
theoretical maximum exposure in the animal diet of rice commodities
treated with DE-638, therefore, livestock feeding studies are not
considered necessary.
    A bioconcentration study on crayfish was conducted to determine the
residues in edible tissues and estimate the bioconcentration factor.
Crayfish (Procambarus clarkii) were exposed for 14 days to \14\C-DE-638
under flow-through conditions at an average exposure concentration of
494 [mu]g/L (Cw), equivalent to approximately 10x the
initial estimated environmental concentration (EEC) based on the
maximum application rate of 50 grams active ingredient/ha and one
hectare rice paddy with 10 centimeters (cm) depth water.
    Plateau of residues in crayfish occurred within 5 days following
initiation of exposure with residues in edible tissues reaching an
average steady-state concentration of 0.009 [mu]g/g (Cf).
The bioconcentration factor (Cf/Cw) was estimated
to be <0.1 milligram per liter/gram (mg/L/g), indicating that
penoxsulam has very low potential to bioconcentrate in edible tissues
of crayfish. Based on the very low residues of <0.01 [mu]g/g (method
limit of detection (LOD) is 0.003 [mu]g/g) in edible tissues of
crayfish exposed to 10x the peak EEC, no tolerance in crayfish is
required.
    2. Analytical method. An analytical method has been developed and
validated to determine the residues of penoxsulam in rice grain, straw,
and processed products. The method was based on liquid chromatography
with positive ion electrospray tandem mass spectrometry molecular size
(LC/MS/MS) with LOD of 0.002 [mu]g/g and limit of quantitation (LOQ) of
0.01 [mu]g/g. The method has been successfully validated by an
independent laboratory.

B. Toxicological Profile

    1. Acute toxicity. The acute toxicity of penoxsulam is considered
low. The acute oral and dermal LD50s were greater than 5,000
milligrams/kilogram (mg/kg), while the acute inhalation LC50
was greater than the highest attainable aerosol concentration (3.50 mg/
L). Only very slight, transient dermal irritation was seen, and mild
eye irritation was noted. Penoxsulam was negative for skin
sensitization in a Magnussen and Kligman maximization test involving
intradermal injection of penoxsulam with an adjuvant.

[[Page 46612]]

    2. Genotoxicity. Penoxsulam was negative for genotoxicity when
tested in in vitro and in vivo systems.
    3. Reproductive and developmental toxicity. Penoxsulam did not have
any effect on reproductive parameters at dose levels that induced
treatment-related effects in parental rats. At the highest dosage
tested (HDT) (300 mg/kg/day), body weights and weight gains in both
males and females were depressed, liver and/or kidney weights were
increased, and histologic changes were noted in the liver (males) and
kidneys (females). At 100 mg/kg/day, increased liver weights were
recorded in males, with no histologic correlate, and histologic changes
noted in the kidneys of females. Transient decreases in pup body
weights were seen at the HDT, but dietary concentrations were targeted
for adults and consumption of treated diets by the pups resulted in
dose levels to the pups approximately 3-fold higher than in adults. A
teratogenic potential was not demonstrated for penoxsulam in either
rats or rabbits.
    4. Subchronic toxicity. Dietary exposure to penoxsulam identified
the liver and/or urinary tract (kidneys and bladder) as target organs
in rats, mice, and dogs following a 4-week and 13-week administration.
Effects on the liver were reflected in increased liver weights and
hepatocellular hypertrophy, but these effects were not associated with
increases in mixed function oxidase (MFO) enzyme activity. Effects
noted in the kidneys included crystal deposition, most likely from
precipitation of penoxsulam from the urine, with resultant irritation,
inflammation, and hyperplasia of renal pelvic transitional epithelium.
Other than the crystal deposition in the kidneys, all effects following
subchronic exposure to rats appeared to be reversible. Very high doses
were associated with significant decreases in body weight, weight gain,
and feed consumption.
    5.  Chronic toxicity. Chronic exposure in the dog indicated that
the renal effects were not exacerbated with long-term exposure.
Following long-term exposure in rats, the kidneys and urinary bladder
were the primary target organs. Histologic changes seen at the end of 2
years of exposure consisted of inflammation and hyperplasia of the
renal pelvic transitional epithelium, crystal deposition in the kidneys
and urinary bladder, and hyperplasia of the mucosa of the urinary
bladder. In the mouse, the liver was the primary target organ, and
histologic changes consisted of hepatocellular hypertrophy. There were
no treatment-related increases in tumors in either rats or mice. The
incidence of mononuclear cell leukemia (Fischer rat leukemia) was
increased in all groups of treated male rats compared to the concurrent
controls. However, the incidences in the treated groups were identical
across a 50-fold increase in dosage, and well within the range of
control values reported in the literature.
    Using the Guidelines for Carcinogen Risk Assessment published
September 24, 1986 (51 FR 33992), it is proposed that penoxsulam be
classified as Group E for carcinogenicity (no evidence of
carcinogenicity) based on the results of carcinogenicity studies in two
species. Dow AgroSciences LLC believes there was no evidence of
carcinogenicity in an 18-month mouse feeding study and a 24-month rat
feeding study at all dosages tested.
    6. Animal metabolism. Orally administered penoxsulam is rapidly
absorbed, excreted and extensively metabolized in both male and female
rats, thus, indicating that penoxsulam is not expected to accumulate in
biological systems. The majority of the residue was associated with the
parent, penoxsulam. Several metabolites were also observed but the vast
majority were <1% of the administered dose. The major route of
metabolism involves O-demethylation, producing the OH-Penoxsulam
metabolite followed by conjugation.
    7. Metabolite toxicology. A metabolism study with penoxsulam in
rice revealed the presence of the parent, a desmethylation metabolite
(5-OH-penoxsulam), and two other polar metabolites, which may represent
conjugates of the desmethylated metabolite. The 5-OH-penoxsulam
metabolite and its glucuronide and glutathione conjugates have also
been identified in the plasma and liver of rats; therefore, plant
metabolites are considered of little toxicological concern.
    8. Neurotoxicity. Penoxsulam has been shown to have no
neurotoxicologic potential based on acute and subchronic studies.
    9. Endocrine disruption. Penoxsulam did not have any effects on
endocrine organs or tissues in mice, rats or dogs in any of the studies
conducted. There were no indications of effects on fetal development in
either rats or rabbits, or on reproductive performance in rats. Based
on the lack of any effects on the endocrine system, penoxsulam is not
considered an endocrine disrupter.

C. Aggregate Exposure

    Dietary exposure. Based on the rapid degradation of penoxsulam, no
surface water or ground water contamination is expected. This agrees
with EPA Tier I modeling carried out on penoxsulam. Therefore, drinking
water will not be a significant route of exposure. Dietary exposure is
very low as previously mentioned. In addition, a rotational crop study
showed no carryover of penoxsulam related residues in any
representative test crop. There are no residential uses for this
compound. As a result, the only potential for exposure is dietary,
which is acceptable. Therefore, aggregation of exposures is not
necessary.

D. Cumulative Effects

    Currently, no methodologies are available to resolve the complex
scientific issues concerning common mechanism of toxicity and
cumulative exposure and risk. EPA has begun a pilot process to study
this issue further through the examination of particular classes of
pesticides. Thus, Dow AgroSciences LLC believes it is appropriate to
consider only the potential risks of penoxsulam in its exposure
assessment.

E. Safety Determination

    1. U.S. population. Using the conservative exposure assumptions
described above, and based on the completeness and reliability of the
toxicity data, the aggregate exposure to penoxsulam, as determined
under the guidance of the FQPA, will utilize no more than 0.1% of the
RfD from the dietary exposure for all subgroups of the U.S. population.
Generally and under the Food Quality Protection Act (FQPA), EPA has no
concern for exposures below 100% of the reference dose (RfD) because
the RfD represents the level at or below which daily dietary exposure
over a lifetime will not pose appreciable risks to human health.
Additionally, the calculated drinking water levels of concern (DWLOC)
was substantially higher than the potential penoxsulam concentration in
water. Therefore, there is a reasonable certainty that no harm will
result to the general U.S. population from aggregate exposure to
penoxsulam residues from proposed use.
    2. Infants and children. In assessing the potential for additional
sensitivity of infants and children to residues of penoxsulam, data
from developmental toxicity studies in rats and rabbits and a multi-
generation reproduction study in the rat are considered. The
developmental toxicity studies are designed to evaluate adverse effects
on the developing organism resulting from pesticide exposure during
prenatal development. Reproduction studies provide information relating
to effects from exposure of both parents to the pesticide on the
reproductive capability and potential systemic toxicity of

[[Page 46613]]

mating animals and on various parameters associated with the well being
of offspring. FFDCA section 408 provides that EPA may apply an
additional safety factor (SF) for infants and children in the case of
threshold effects to account for prenatal and postnatal toxicity and
the completeness of the data base. Based on the current toxicological
data requirements, the data base for penoxsulam relative to prenatal
and postnatal effects for children is complete. Overall, penoxsulam had
no effect on reproduction or embryo-fetal development at any dosage
tested. No quantitative or qualitative susceptibility was seen
following prenatal and postnatal exposures. In a rabbit developmental
toxicity study, effects on in-utero survival were observed only at a
dose level where clear maternal toxicity was seen. In a 2-generation
reproductive toxicity study in rats, no effects on reproductive
performance were observed and effects on neonatal growth were seen only
at a dose level where parental toxicity was seen. In addition, the no
observed adverse effect level (NOAEL) in the chronic rat study (5 mg/
kg/day), used to calculate the chronic RfD (0.05 mg/kg/day), is already
lower than the acute NOAEL from the rabbit developmental study (25 mg/
kg/day). Therefore, an additional FQPA uncertainty factor (UF) is not
needed and the RfD at 0.05 mg/kg/day is appropriate for assessing risk
to infants and children. Using the conservative exposure assumptions
previously described, the percent RfD utilized by the potential
exposure to residues of penoxsulam on rice is <0.1% for non-nursing
infants, the population subgroup predicted to be potentially the most
highly exposed. Risk for developmental toxicity from acute exposure to
penoxsulam was evaluated for pregnant females (13+ years old). The
high-end margin of exposure value of >300,000 (0.03% of acute RfD) is
well above the acceptable 100. Therefore, based on the completeness and
reliability of the toxicity data and the conservative exposure
assessment, Dow AgroSciences LLC concludes with reasonable certainty
that no harm will result to infants and children, females 13+ years old
and the prenatal development of infants from the aggregate exposure to
penoxsulam residues.

F. International Tolerances

    There are no Codex maximum residue levels established for residues
of penoxsulam on/in rice and rice.

[FR Doc. 03-20015 Filed 8-5-03; 8:45
BILLING CODE 6560-50-S