[Federal Register Volume 69, Number 111 (Wednesday, June 9, 2004)]
[Notices]
[Pages 32346-32351]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-12703]


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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2004-0148; FRL-7360-2]


Pymetrozine; 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-2004-0148, must be 
received on or before July 9, 2004.

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: [email protected].

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. 
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. 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 code 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. 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-2004-0148. 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

[[Page 32347]]

electronic public docket and 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 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 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-2004-0148. 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-2004-0148. 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-2004-0148.
    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-2004-0148. 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

[[Page 32348]]

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:May 24, 2004.
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 Syngento Crop Protection, the pesticide's registrant, and 
submitted by the 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

 PP 2E6467

    EPA has received a pesticide petition (PP 2E6467) from the IR-4 
Project, Project Centre for Minor Crop Pest Management, Rutgers, The 
State University of New Jersey, 681 U.S. Highway 1 South, 
North Brunswick, NJ 8920-3390 proposing, pursuant to section 408(d) of 
FFDCA, 21 U.S.C. 346a(d), to amend 40 CFR part 180, by establishing a 
tolerance for residues of the insecticide pymetrozine (1,2,4-triazin-
3(2H)-one,4,5-dihydro-6-methyl-4-(3-pyridinylmethylene)amino in or on 
the raw agricultural commodity asparagus at 0.02 parts per million 
(ppm). 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 metabolism of pymetrozine in plants is 
understood for the purposes of the proposed tolerances. Studies in 
rice, tomatoes, cotton and potatoes gave similar results. The metabolic 
pathways have demonstrated that pymetrozine, per se, is the residue of 
concern for tolerance setting purposes.
    2. Analytical method. Syngenta has submitted an analytical method 
(AG-643) for the determination of pymetrozine in crop substrates. The 
limit of detection (LOD) for the analytical method is 1.0 ng and the 
limit of quantification (LOQ) is 0.02 ppm. Samples are extracted, 
purified with solid-phase and liquid-liquid partitions and analyzed by 
high performance liquid chromotography (HPLC). Analytical method has 
undergone independent laboratory validation. The pymetrozine Analytical 
Method AG-643 is proposed as the tolerance enforcement method. Syngenta 
has also submitted an analytical method (AG-647) for the determination 
of the major crop metabolite of pymetrozine, GS-23199. GS-23199 is 
considered a marker for metabolite residues. This metabolite is not 
proposed as part of the tolerance expression. Samples are extracted, 
purified with solid-phase and/or liquid-liquid partitions and analyzed 
by HPLC.
    3. Magnitude of residues. Residue data were generated for 
pymetrozine for tolerance setting and dietary exposure estimates. Data 
were also generated for a major metabolite, GS-23199. Adequate residue 
trials were performed for pymetrozine on the uses proposed in this 
notice of filing.

B. Toxicological Profile

    1. Acute toxicity. In general, pymetrozine has low acute toxicity 
being classified as Toxicity Category III for acute dermal and primary 
eye irritation studies and Toxicity Category IV for acute oral, acute 
inhalation and primary dermal studies. The oral lethal dose 
(LD)50 in rats is >5,820 milligrams/kilogram (mg/kg) for 
males and females, combined. The rat dermal LD50 is>2,000 
mg/kg and the rat inhalation lethal concentration (LC)50 is 
> 1.8 milligrams/liter (mg/L) air. Pymetrozine is a slight sensitizer 
in guinea pigs. End-use water-dispersible granule formulations of 
pymetrozine have similar low acute toxicity profiles.
    2. Genotoxicity. Pymetrozine did not induce point mutations in 
bacteria (Ames assay in Salmonella typhimurium and Escherichia coli) or 
in cultured mammalian cells (Chinese hamster V79) and was not genotoxic 
in an in vitro unscheduled DNA synthesis assay in rat hepatocytes. 
Chromosome aberrations were not observed in an in vitro test using 
Chinese hamster ovary cells and there were no clastogenic or aneugenic 
effects on mouse bone marrow cells in an in vivo mouse micronucleus 
test. These studies show that pymetrozine is not mutagenic or 
genotoxic.
    3. Reproductive and developmental toxicity. In a teratology study 
in rats, pymetrozine caused decreased body weights and food consumption 
in females given 100 and 300 mg/kg/day during gestation. This maternal 
toxicity was accompanied by fetal skeletal anomalies and variations 
consistent

[[Page 32349]]

with delayed ossification. The no observed adverse effect level (NOAEL) 
for maternal and fetal effects in rats was 30 mg/kg/day. In a rabbit 
teratology study, maternal death, reduced body weight gain and food 
consumption were observed at 125 mg/kg/day (highest dose tested). 
Embryo and feto toxicity (abortion in one female and total resorptions 
in two females) accompanied maternal toxicity. Body weight and food 
consumption decreases, early resorptions and postimplantation losses 
were also observed in maternal rabbits given 75 mg/kg/day. There was an 
increased incidence of fetal skeletal anomalies and variations at these 
maternally toxic doses. The NOAEL for maternal and fetal effects in 
rabbits was 10 mg/kg/day. Pymetrozine is not teratogenic in rats or 
rabbits. In a 2-generation reproduction study in rats, parental body 
weights and food consumption were decreased, liver and spleen weights 
were reduced and histopathological changes in liver, spleen and 
pituitary were observed at approximately 110-440 mg/kg/day (highest 
dose tested). Liver hypertrophy was observed in a few parental males at 
approximately 10-40 mg/kg/day. Reproductive parameters were not 
affected by treatment with pymetrozine. The NOAEL for reproductive 
toxicity is approximately 110-440 mg/kg/day. The NOAEL for toxicity to 
adults and pups is approximately 1-4 mg/kg/day.
    4. Subchronic toxicity. Pymetrozine was evaluated in 13-week 
subchronic toxicity studies in rats, dogs and mice. Liver, kidneys, 
thymus and spleen were identified as target organs. The NOAEL was 33 
mg/kg/day in rats and 3 mg/kg/day in dogs. In mice, increased liver 
weights and microscopical changes in the liver were observed at all 
doses tested. The NOAEL in mice was <198 mg/kg/day. No dermal 
irritation or systemic toxicity occurred in a 28-day repeated dose 
dermal toxicity study with pymetrozine in rats given 1,000 mg/kg/day. 
Minimum direct dermal absorption (1.1%) of pymetrozine was detected in 
rats over a 21-hour period of dermal exposure. Maximum radioactivity 
left on or in the skin at the application site and considered for 
potential absorption was 11.9%.
    5. Chronic toxicity. Based on chronic toxicity studies in the dog 
and rat, a reference dose (RfD) of 0.0057 mg/kg/day is proposed for 
pymetrozine. This RfD is based on a NOAEL of 0.57 mg/kg/day established 
in the chronic dog study and an uncertainty factor of 100 to account 
for interspecies extrapolation and interspecies variability. Minor 
changes in blood chemistry parameters, including higher plasma 
cholesterol and phospholipid levels, were observed in the dog at the 
lowest observed adverse effect level (LOAEL) of 5.3 mg/kg/day. The 
NOAEL established in the rat chronic toxicity study was 3.7 mg/kg/day 
and was based on reduced body weight gain and food consumption, 
hematology and blood chemistry changes, liver pathology and biliary 
cysts.
    The carcinogenic potential of pymetrozine has been evaluated in 
rats and mice. A liver tumor response was observed in male and female 
mice and female rats at high doses exceeding the maximum tolerated 
dose. These liver tumors correlated with reversible biochemical 
(induction of liver metabolizing enzymes) and morphological (hepatocyte 
and smooth endoplasmic reticulum proliferation) changes and a 
reversible saturation of metabolic processes. EPA has assigned a cancer 
classification of ``likely'' to pymetrozine and calculated a Q1* value. 
However, Syngenta believes that the mechanism of action leading to 
liver tumors at maximum tolerated doses is a non-genotoxic threshold 
event and should be regulated as such.
    6. Animal metabolism. The metabolism of pymetrozine in the rat is 
well understood. Metabolism involves oxidation of substituent groups of 
the triazine ring yielding ketones and carboxylic acids. Hydrolysis of 
the enamino bridge between rings results in products that are further 
metabolized. The metabolic pathways in animals and plants are similar.
    7. Metabolite toxicology. The residue of concern for tolerance 
setting purposes is the parent compound. Metabolites of pymetrozine are 
considered to be of equal or lesser toxicity than the parent.
    8. Endocrine disruption. Pymetrozine does not belong to a class of 
chemicals known or suspected of having adverse effects on the endocrine 
system. There is no evidence that pymetrozine has any effect on 
endocrine function in developmental and reproduction studies. 
Furthermore, histological investigation of endocrine organs in chronic 
dog, rat and mouse studies did not indicate that the endocrine system 
is targeted by pymetrozine.

C. Aggregate Exposure



    1. Dietary exposure. Tier III acute, chronic and lifetime dietary 
exposure evaluations were made using the Dietary Exposure Evaluation 
Model (DEEMTM), version 7.81 from Exponent. Empirically 
derived processing studies for cotton oil (0.62X), potato chips 
(1.00X), tomato paste (0.57X) and tomato puree (0.21X) were used in 
these assessments. All consumption data for these assessments was taken 
from the USDA's Continuing Survey of Food Intake by Individuals (CSFII) 
with the 1994-1996 consumption database and the Supplemental CSFII 
children's survey (1998) consumption database. These exposure 
assessments included all registered uses on cotton, pecans, hops, 
cucurbits, tuberous and corm vegetables, Brassica (cole) leafy 
vegetables, leafy vegetables, fruiting vegetables, and a pending new 
use on asparagus. Secondary residues in animal commodities were not 
included in the exposure assessment since no tolerance values exist for 
residues in meat and milk and a three-level dairy feeding study in 
lactating livestock showed no residues at any of the feeding levels. 
Additionally, the highest feeding level (10 ppm) used in this study was 
at least 10-fold higher than what would be expected in treated feed.
    a. Food. For the purposes of assessing the potential dietary 
exposure, Syngenta Crop Protection has estimated aggregate exposure 
from all crops for which tolerances are established or proposed. These 
assessments utilized residue data from field trials where pymetrozine 
was applied at the maximum intended use rate and samples were harvested 
at the minimum pre-harvest interval (PHI) to obtain maximum residues. 
Percent of crop treated values were values were taken from the 
Biological and Economic Analysis Division's (BEAD's) latest pymetrozine 
estimate compiled on August 15, 2001.
    i. Chronic exposure. The chronic reference dose (RfD) of 
pymetrozine is 0.0038 mg/kg bwt/day and is based on a NOAEL of 0.38 mg/
kg bwt/day from a chronic feeding study in rats and a 100X uncertainty 
factor. No additional FQPA safety factor was applied. The pymetrozine 
Tier III chronic dietary exposure assessment was based upon field trial 
residue results. For the purpose of aggregate risk assessment, the 
exposure values were expressed in terms of margin of exposure (MOE), 
which was calculated by dividing the NOAEL by the exposure for each 
population subgroup. In addition, exposure was expressed as a percent 
of the chronic reference dose (%RfD). Chronic exposure to the most 
exposed sub-population (children 1-2 years old) resulted in a MOE of 
1,203 (1.1% of the chronic RfD of 0.0038 mg/kg bwt/day). Since the 
benchmark MOE for this assessment was 100 and the EPA generally has no 
concern for exposures below 100% of the RfD, Syngenta believes that 
there is a reasonable

[[Page 32350]]

certainty that no harm will result from dietary (food) exposure to 
residues arising from the current and proposed uses of pymetrozine.
    ii. Acute exposure. The aRfD for pymetrozine for all populations 
except females (13+ years old) is 0.42 mg/kg-bw/day and is based on a 
lowest observable adverse effect level (LOAEL) of 125 mg/kg/day from an 
acute neurotoxicity study in rats and a 300X uncertainty factor. The 
acute population adjusted-dose (aPAD) for females (13+ years old) is 
0.10 mg/kg bwt/day and is based on a NOAEL of 10 mg/kg bwt/day from a 
rabbit developmental toxicity study and a 100X uncertainty factor. A 
Tier III probabilistic acute dietary analysis was conducted with a full 
distribution of residues for all registered commodities and asparagus. 
Each residue distribution was adjusted for percent of crop treated by 
adding zeroes to the distribution to account for the percent of crop 
not treated. Acute exposure to females (13-50 years old) resulted in a 
MOE of 19,881 (0.5% of the acute population adjusted dose (aPAD) of 
0.10 mg/kg bwt/day). Acute exposure to the most exposed sub-population 
children 1-2 years old resulted in a MOE of 123,640 (0.2% of the acute 
RfD of 0.0038 mg/kg bwt/day). Since the benchmark MOE for this 
assessment was 300 and since EPA generally has no concern for exposures 
below 100% of the RfD, Syngenta believes that there is a reasonable 
certainty that no harm will result from dietary (food) exposure to 
residues arising from the current and proposed uses of pymetrozine.
    iii. Lifetime exposure. Lifetime risk to pymetrozine was evaluated 
by comparing exposure to a Q* value of 0.0119 (mg/kg bwt/
day)-1 based on male mouse liver benign hepotomas and/or 
carcinomas combined. Lifetime risk for the U.S. population was 3.49 x 
10-7. Since this value is below the EPA's lifetime risk 
limit of 1.00 x 10-6, these results indicate that there is a 
reasonable certainty of no harm resulting from lifetime exposures 
through the consumption of pymetrozine-treated commodities.
    b. Drinking water. Drinking water exposure to pymetrozine was 
evaluated based on the crop uses above with EPA's surface water Tier I 
model (Generic Expected Environmental Concentration (GENEEC)). Hops, 
with three applications at 0.1875 lb a.i./acre, gave the highest total 
application and this rate was; therefore, used in GENEEC to estimate 
the chronic, acute and lifetime estimated environmental concentrations 
(EECs) for drinking water.

    1. Acute exposure--i. The acute EEC for pymetrozine was 4.27 ppb 
and the chronic EEC was 0.31 parts per billion (ppb.) The calculated 
acute DWLOC for the most sensitive sub-population children 1-2 years 
old was 4,190 ppb. Since acute EEC value of 4.27 ppb is less than the 
calculated acute DWLOC, these results indicate that there is a 
reasonable certainty of no harm resulting from acute drinking water 
exposures.
    ii. Chronic exposure. The chronic EEC for pymetrozine was 0.031 
ppb. The calculated chronic DWLOC for the most sensitive sub-population 
children 1-2 years old was 38 ppb. Since the chronic EEC of 0.31 ppb is 
below this value, these results indicate that there is a reasonable 
certainty of no harm resulting from chronic drinking water exposures.
    iii. Lifetime exposure. Using a Q* value of 0.0119 mg/kg bwt/
day-1 and a chronic EEC of 0.31 ppb, the risk to a typical 
70 kg adult drinking 2 liters of water per day would be at 1.05 x 10-
7.
    2. Non-dietary exposure. Pymetrozine is registered on ornamentals 
and exposure could occur through post-application re-entry to treated 
plants. Syngenta believes that risks due to short-term, intermediate-
term or chronic exposure are either not applicable or insignificant.

D. Cumulative Effects

    EPA is also required to consider the potential for cumulative 
effects of pymetrozine and other substances that have a common 
mechanism of toxicity. Pymetrozine belongs to a chemical class known as 
pyridine azomethines and exhibits a unique mode of action. EPA 
consideration of a common mechanism of toxicity is not appropriate at 
this time since EPA does not have information to indicate that toxic 
effects produced by pymetrozine would be cumulative with those of any 
other chemical compounds; thus only the potential risks of pymetrozine 
are considered in this exposure assessment.

E. Safety Determination

    1. Acute risk. Exposure to pymetrozine residues in food will occupy 
no more than 0.2% of the RfD of 0.42 mg/kg bwt/day for the most 
sensitive population subgroup children 1-2 years old. Residue values 
used for these dietary risk assessments were from field trials and 
incorporated percent of crop treated information in the residue 
distributions. Acute dietary exposure estimates were determined at the 
99.9th percentile of acute exposure. Estimated 
concentrations of pymetrozine residues in surface water and ground 
water were below the calculated acute drinking water level of 
comparison (DWLOC). Therefore, Syngenta does not expect acute aggregate 
risk to pymetrozine residues from food and water sources to exceed the 
level of concern for acute dietary exposure.
    2. Chronic risk. Chronic dietary exposure to pymetrozine residues 
in food for the most sensitive population subgroup (children 1-2 years 
old) occupied 1.1% of the chronic RfD of 0.0038 mg/kg bwt/day. Residue 
values used for these dietary risk assessments were from field trials 
and incorporated percent of crop treated information, as indicated 
above. Estimated concentrations of pymetrozine residues in surface 
water and ground water were below the calculated chronic drinking water 
level of comparison (DWLOC). Syngenta believes that the chronic 
aggregate risk from pymetrozine residues in food and drinking water 
would therefore not be expected to exceed the EPA's level of concern.
    3. Lifetime risk. The chronic lifetime dietary risk to pymetrozine 
residues in food for the U.S. population was 3.49 x 10-7, 
which is below EPA's level of concern (1.0 x 10-6). Residue 
values used for this lifetime risk assessment were from field trials 
and incorporated percent of crop treated information, as indicated 
above. The estimated concentrations of pymetrozine residues in surface 
water and ground water are lower than the calculated lifetime DWLOC. 
Therefore, Syngenta concludes that the aggregate lifetime risk from 
pymetrozine residues in food and drinking water sources would therefore 
not be expected to exceed EPA's level of concern for lifetime dietary 
exposure.
    Syngenta has considered the potential aggregate exposure from food, 
water and non-occupational exposure routes and concluded that aggregate 
exposure is not expected to exceed 100% of the acute, chronic and 
lifetime reference doses. Therefore, Syngenta believes there is a 
reasonable certainty that no harm will result to infants and children 
from the aggregate exposures to pymetrozine.

F. International Tolerances

    There are no established European Codex, Canadian, or Mexican 
maximum residue limits for pymetrozine. There are provisional MRLs in 
Germany for hops 10 ppm and potatoes 0.02 ppm. The European Union is 
currently evaluating a proposed tolerance of 5 ppm on hops. At this 
time, international

[[Page 32351]]

harmonization of residue levels is not an issue.

[FR Doc. 04-12703 Filed 6-8-04; 8:45 am]
BILLING CODE 6560-50-S