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Dimethomorph; Notice of Filing Pesticide Petitions to Establish Tolerances for Certain Pesticide Chemical in or on Food

Note: EPA no longer updates this information, but it may be useful as a reference or resource.


 
[Federal Register: August 20, 2003 (Volume 68, Number 161)]
[Notices]
[Page 50138-50143]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20au03-48]


[[Page 50138]]

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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2003-0262; FRL-7321-7]

 
Dimethomorph; Notice of Filing Pesticide Petitions to Establish 
Tolerances for 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 pesticide 
petitions 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-2003-0262, must be 
received on or before September 19, 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: Shaja R. Brothers, Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001; telephone number: (703) 308-3194; e-mail address: 
brothers.shaja@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:
    ?  Industry (NAICS 111)
    ?  Crop production (NAICS 112)
    ?  Animal production (NAICS 311)
    ?  Food 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-2003-0262. 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.regulations.gov/ 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 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

[[Page 50139]]

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-2003-0262. 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-2003-0262. 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-2003-0262.
    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-2003-0262. 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 pesticide petitions 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 11, 2003.
Peter Caulkins,
Acting Director, Registration Division, Office of Pesticide Programs.

Summary of Petitions

    The petitioner's summary of the pesticide petitions are printed 
below as required by FFDCA section 408(d)(3). The summary of the 
petitions were prepared by BASF Corporation and represents the view of 
BASF Corporation. 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 2E6483 and PP 3E6558

     EPA has received pesticide petitions (2E6483 and 3E6558) from 
Interregional Research Project Number 4 (IR-4), 681 U.S. Highway 
#1 South, North Brunswick, NJ 08902-3390 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 180.493 by establishing tolerances 
for residues of dimethomorph, (E,Z)4-[3-(4-chlorophenyl)-3-(3,4-
dimethoxyphenyl)-1-oxo-2-propenyl morpholine in or on the following raw 
agricultural commodities: Vegetable, fruiting, group 8 at 2.0 parts per 
million (ppm) (2E6483), brassica, leafy, greens,

[[Page 50140]]

(subgroup 5B), and turnip, tops at 20 ppm (PP 3E6558), taro, leaves at 
6.0 ppm (3E6558), and taro, roots at 0.5 ppm (3E6558). IR-4 also 
proposes to delete the existing tolerance for tomato, fruit at 0.5 ppm. 
Tomato is included in the proposed tolerance for the fruiting vegetable 
group 8 at 2.0 ppm. 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 
petitions. Additional data may be needed before EPA rules on the 
petitions. This summary has been prepared by BASF Corporation, Research 
Triangle Park, NC 27709.

A. Residue Chemistry

    1. Plant metabolism. Based upon the results of metabolism studies 
conducted on potato, grape, and lettuce, the nature of the residues in 
plants is considered to be understood.
    2. Analytical method. A reliable method for the determination of 
dimethomorph residues in fruiting vegetables (except cucurbits) (crop 
group 8), leafy brassica greens (subgroup 5B), turnip greens, taro 
leaves and roots exists; this method is the FDA Multi-Residue Method, 
Protocol D, as published in the Pesticide Analytical Manual I.
    3. Magnitude of residues. The magnitude of residues for the 
proposed tolerances are adequately understood.

B. Toxicological Profile

    1. Acute toxicity--i. Oral lethal dose LD50 studies were 
conducted on dimethomorph technical:
    a. An acute oral toxicity study in the Sprague-Dawley rat for 
dimethomorph technical with a LD50 of 4,300 milligrams/
kilogram body weight (mg/kg bwt) for males and 3,500 mg/kg bwt for 
females. Based upon EPA toxicity criteria, the acute oral toxicity 
category for dimethomorph technical is Category III or slightly toxic.
    b. An acute toxicity study in the CD-1 mouse for dimethomorph 
technical with a LD50 of greater than 5,000 mg/kg bwt for 
males and 3,699 mg/kg/bwt for females. Based on the EPA toxicity 
category criteria, the acute oral toxicity category for dimethomorph 
technical is Category III or slightly toxic.
    ii. Oral LD50 studies were conducted on the two isomers 
(E and Z) alone:
    a. An acute oral toxicity study in the Wistar rat for the E-isomer 
with a LD50 greater than 5,000 mg/kg bwt for males and 
approximately 5,000 mg/kg bwt for females.
    b. An acute oral toxicity study in the Wistar rat for the Z-isomer 
with a LD50 greater than 5,000 mg/kg bwt for both males and 
females.
    iii. An acute dermal toxicity study in the Wistar rat for 
dimethomorph technical with a dermal LD50 greater than 5,000 
mg/kg bwt for both males and females. Based on the EPA toxicity 
category criteria, the acute dermal toxicity category for dimethomorph 
is Category IV or relatively non-toxic.
    iv. A 4-hour inhalation study in Wistar rats for dimethomorph 
technical with a lethal concentration LC50 greater than 4.2 
milligram per liter (mg/L) for both males and females. Based on the EPA 
toxicity category criteria, the acute inhalation toxicity category for 
dimethomorph technical is Category IV or relatively non-toxic.
    v. A skin irritation study was performed using New Zealand White 
rabbits. Based on EPA's toxicity criteria, the skin irritation toxicity 
category for dimethomorph technical in this study is Category IV or 
non-to-slightly irritating.
    vi. An eye irritation study using New Zealand white rabbits 
demonstrated dimethomorph technical produced moderate conjunctival 
redness, slight to moderate chemosis and slight discharge 3 hours after 
treatment. Based on EPA's toxicity criteria, the eye toxicity category 
for dimethomorph technical is Category III (slightly to moderately 
irritating).
    2. Genotoxicity.--i. Salmonella reverse gene mutation assays (2 
studies) were negative up to a limit dose of 5,000 g/plate. Chinese 
hamster lung V79 cells were negative for mutations at the HGPRT locus 
at up to toxic doses in two studies.
    ii. Two Chinese hamster lung (V79 cells) structural chromosomal 
studies were reportedly positive for chromosomal aberrations at the 
highest dose tested (HDT) (160 g/ml/-S9; 170 g/ml/+S9). However, 
dimethomorph induced only a weak response in increasing chromosome 
aberrations in this test system. In addition, these results were not 
confirmed in two micronucleus tests under in vivo conditions.
    iii. Structural chromosomal aberration studies were weakly positive 
in human lymphocytic cultures, but only in S9 activated cultures 
treated at 422 g/mL, the HDT, which was strongly cytotoxic. No increase 
in chromosomal aberrations was observed in the absence of S9 activation 
at all doses. Furthermore, the positive clastogenic response observed 
under the in vitro conditions was not confirmed in two in vivo 
micronucleus assays.
    iv. Micronucleus assay (2 studies) indicated that dimethomorph was 
negative for inducing micronuclei in bone marrow cells of mice 
following i.p. administration of doses up to 200 mg/kg or oral doses up 
to the limit dose of 5,000 mg/kg. Thus, dimethomorph was found to be 
negative in these studies for causing cytogenic damage in vivo.
    v. Dimethomorph was negative for inducing unscheduled DNA 
synthesis, in cultured rat liver cells, at doses up to 250 grams per 
milliliter (g/ml), a weakly cytotoxic level.
    vi. Dimethomorph was negative for transformation in Syrian hamster 
embryo cells treated, in the presence and absence of activation, up to 
cytotoxic concentrations (265 g/mL/+S9; 50 g/mL/-S9).
    3. Reproductive and developmental toxicity--i. A rat developmental 
toxicity study with a lowest observed adverse effect level (LOAEL) for 
maternal toxicity of 160 mg/kg/day and a NOAEL for maternal toxicity of 
60 mg/kg/day. The NOAEL for developmental toxicity is 60 mg/kg/day. 
Dimethomorph is not teratogenic in the Sprague-Dawley rat.
    ii. A rabbit development toxicity study with a LOAEL for maternal 
toxicity of 650 mg/kg/day and a NOAEL for maternal toxicity of 300 mg/
kg/day. The NOAEL for developmental toxicity is 650 mg/kg/day, the HDT. 
Dimethomorph is not teratogenic in the New Zealand white rabbit.
    iii. A two-generation rat reproduction study with a LOAEL for 
parental systemic toxicity of 1,000 ppm, or approximately 80 mg/kg/day, 
and a NOAEL for parental systemic toxicity of 300 ppm, or approximately 
24 mg/kg/day. The NOAEL for fertility and reproductive function was 
1,000 ppm, the highest concentration tested (HCT), or approximately 80 
mg/kg bwt/day.
    4. Subchronic toxicity--i. A 90-day dietary study in Sprague-Dawley 
rats with a NOAEL of greater than or equal to 1,000 ppm, the HCT 
tested, or approximately 73 mg/kg/day for males and 82 mg/kg/day for 
females.
    ii. A 90-day dog dietary study with a NOAEL of 450 ppm, or 
approximately 15 mg/kg/day, and a LOAEL of 1,350 ppm, or approximately 
43 mg/kg/day.
    5. Chronic toxicity-i. A 2-year chronic toxicity study in Sprague-
Dawley rats with a NOAEL of 200 ppm or approximately 9 mg/kg/day for 
males and 12 mg/kg/day for females. The LOAEL for systemic toxicity is 
750 ppm, or approximately 36 mg/kg/day for males and 58 mg/kg/day for 
females.
    ii. A 1-year chronic toxicity study in dogs with a NOAEL of 450 
ppm, or approximately 14.7 mg/kg/day and a

[[Page 50141]]

LOAEL of 1,350, or approximately 44.6 mg/kg/day.
    iii. A 2-year oncogenicity study in Sprague-Dawley rats with a 
NOAEL for systemic toxicity of 200 ppm, or approximately 9 mg/kg/day 
for males and 11 mg/kg/day for females. The LOAEL for systemic toxicity 
was 750 ppm, or approximately 34 mg/kg/day for males and 46 mg/kg/day 
for females. There was no evidence of increased incidence of neoplastic 
lesions in treated animals. The NOAEL for oncogenicity is 2,000 ppm, 
the Highest Concentration Tested (HCT), or approximately 95 mg/kg/day 
for males and 132 mg/kg/day for females.
    iv. A 2-year oncogenicity study in CD-1 mice with a NOAEL for 
systemic toxicity of 100 mg/kg/day and a LOAEL of 1,000 mg/kg/day. 
There was no evidence of increased incidence of neoplastic lesions in 
treated animals. The NOAEL for oncogenicity is 1,000 mg/kg/day, the 
HDT.
    6. Animal metabolism. Results from the livestock and rat metabolism 
studies show that orally administered dimethomorph was rapidly excreted 
by the animals. The principal route of elimination is the feces.
    7. Metabolite toxicology. There were no metabolites identified in 
plant or animal commodities which require regulation.
    8. Endocrine disruption. Collective organ weights and 
histopathological findings from the two-generation reproduction study 
in rats, as well as from the subchronic and chronic toxicity studies in 
two or more animal species, demonstrate no apparent estrogenic effects 
or effects on the endocrine system. There is no information available 
which suggests that dimethomorph technical would be associated with 
endocrine effects.

C. Aggregate Exposure

    1. Dietary exposure. The CARES 1.1 model with the CSFII/FCID 
consumption data were used to calculate chronic and acute exposure 
estimates. Result exposure estimates 99.9th percentile were 
compared against the dimethomorph reference dose (RfD) and chronic 
population adjusted dose (cPAD).
    i. Food. The dietary assessment analysis followed an initial tier 
approach with only one minor refinement. Tolerance values, default 
processing factors, and 100% crop treated (CT) values were assumed in 
the assessment. The only minor refinement was including percent crop 
treated values for potatoes (2.2%), tomatoes (0.1%), cucumbers (2.9%), 
and pumpkin (13.6%). Vegetables (fruiting, bulb, cucurbit), lettuce 
(leaf, head), grapes (including raisins), potatoes, hops, grain, 
brassica (leafy greens), leaves of root and tuber vegetables, and taro 
roots as the target crops were also considered for this analysis.
    a. Chronic. Results of the chronic dietary exposure assessment for 
dimethomorph (BAS 550 F) are listed in Table 1. The estimated chronic 
dietary exposure for all current and pending commodities ranged from 
7.5% to 15.2% of the %cPAD (0.1 mg/kg bwt/day) for all subpopulations.

                    Table 1.-Chronic Dietary Exposure Assessment for Dimethomorph (BAS 550 F)
----------------------------------------------------------------------------------------------------------------
                                  Exposure Estimate (mg/kg bwt/
           Population                         day)                       %cRfD                    %cPAD
----------------------------------------------------------------------------------------------------------------
Birth to 1-year                                       0.007972                     7.97                     7.97
----------------------------------------------------------------------------------------------------------------
1-2 years                                              0.01513                    15.13                    15.13
----------------------------------------------------------------------------------------------------------------
3-5 years                                              0.01331                    13.31                    13.31
----------------------------------------------------------------------------------------------------------------
1-6 years                                              0.01512                    15.12                    15.12
----------------------------------------------------------------------------------------------------------------
6-12 years                                            0.007794                     7.79                     7.79
----------------------------------------------------------------------------------------------------------------
Teens 13-19 years                                     0.007482                     7.48                     7.48
----------------------------------------------------------------------------------------------------------------
Females 13-49 years                                   0.007771                     7.77                     7.77
----------------------------------------------------------------------------------------------------------------
Males 20-49 years                                     0.006853                     6.85                     6.85
----------------------------------------------------------------------------------------------------------------
Adults 50+ years                                      0.007548                     7.55                     7.55
----------------------------------------------------------------------------------------------------------------

    b. Acute. Exposure estimates for the dimethomorph acute dietary 
assessment ranged from 0.064 to 0.174 mg/kg bwt/day for all 
subpopulations (Table 2). The %aRfd and %aPAD were not applicable for 
the acute dietary assessment since toxicology studies have shown that 
dimethomorph poses no acute dietary risk.

                    Table 2.--Acute Dietary Exposure Assessment for dimethomorph (BAS 550 F)
----------------------------------------------------------------------------------------------------------------
                                  Exposure Estimate (mg/kg bwt/
           Population                         day)                       %aRfD                    %aPAD
----------------------------------------------------------------------------------------------------------------
Birth to 1-year                                         0.1736                       NA                       NA
----------------------------------------------------------------------------------------------------------------
1-2 years                                               0.1742                       NA                       NA
----------------------------------------------------------------------------------------------------------------
3-5 years                                               0.1584                       NA                       NA
----------------------------------------------------------------------------------------------------------------
1-6 years                                               0.1654                       NA                       NA
----------------------------------------------------------------------------------------------------------------
6-12 years                                             0.09621                       NA                       NA
----------------------------------------------------------------------------------------------------------------

[[Page 50142]]


Teens 13-19 years                                      0.07855                       NA                       NA
----------------------------------------------------------------------------------------------------------------
Females 13-49 years                                    0.07306                       NA                       NA
----------------------------------------------------------------------------------------------------------------
Males 20-49 years                                      0.06386                       NA                       NA
----------------------------------------------------------------------------------------------------------------
Adults 50 + years                                      0.07058                       NA                       NA
----------------------------------------------------------------------------------------------------------------

     Results of the chronic and acute dietary exposure analysis 
demonstrate a reasonable certainty that no harm to the general U.S. 
population or any subpopulation would results from the use of 
dimethomorph on vegetables (fruiting, bulb, cucurbit), lettuce (leaf, 
head), grapes (including raisins), potatoes, hops, grain, brassica 
(leafy greens), leaves of root and tuber vegetables, and taro root.
    ii. Drinking water. EPA's Pesticide Root Zone Model/Exposed 
Analysis Modeling System (PRZM/EXAMS) and Screening Concentration in 
Groundwater (SCI-GROW) models were used to estimate the maximum 
dimethomorph concentrations in surface water and ground water, 
respectively. Results for the chronic drinking water assessment are 
listed in Table 3.

                          Table 3.--Chronic Drinking Water Assessment for Dimethomorph
----------------------------------------------------------------------------------------------------------------
                                                                                               Children birth to
         DWLOC chronic          Adult males 20-49    Adult females 13-49       Children 1-6            1
----------------------------------------------------------------------------------years-------------------------
No effect level                                 9                        9                  9                  9
-----------------------------------------------------------------------------------------------
Safety factor                                 100                      100                100                100
-----------------------------------------------------------------------------------------------
RfD=                                         0.09                     0.09               0.09               0.09
-----------------------------------------------------------------------------------------------
cPAD                                         0.09                     0.09               0.09               0.09
-----------------------------------------------------------------------------------------------
A) Chronic food (mg/kg/day)              0.006853                 0.007771            0.01512           0.007972
-----------------------------------------------------------------------------------------------
B) Residential (mg/kg/day)                      0                        0                  0                  0
-----------------------------------------------------------------------------------------------
water cPAD-(A+B)                       0.08314700               0.10222900         0.07488000         0.08202800
-----------------------------------------------------------------------------------------------
DWLOC chronic [mu]g/L                        2910                     3067                749                820
-----------------------------------------------------------------------------------------------
                                                      DEC's
----------------------------------------------------------------------------------------------------------------
PRZM/EXAMS (EFED) surface                   12.65                    12.65              12.65              12.65
 water ([mu]g/L)
-------------------------------
Sci-Grow (EFED) ground water                 0.26                     0.26               0.26               0.26
----------------------------------------------------------------------------------------------------------------

    2. Aggregate exposure (diet + water). The aggregate exposure of 
dimethomorph residues for food and drinking water is summarized in 
Table 4 below. Currently dimethomorph (BAS 550 F) is not considered for 
residential use and therefore residential exposure was not included in 
the aggregate exposure assessment.

                                                Table 4.--Aggregate Exposure of Dimethomorph (BAS 550 F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                      Exposure                          Infants (0-1 years)      Children (1-6 years)     Males (20-49 years)     Females (13-49 years)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          FOOD
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acute exposure (mg/kg bwt/day)                                         0.1736                   0.1654                  0.06386                  0.07306
-----------------------------------------------------
Chronic exposure (mg/kg bwt/day)                                     0.007972                  0.01512                 0.006853                 0.007771
-----------------------------------------------------
%aRfD and %aPAD                                                            NA                       NA                       NA                       NA
-----------------------------------------------------
%cRfD and %cPAD                                                          7.97                    15.12                     6.85                     7.77
-----------------------------------------------------
                                                                          WATER
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acute exposure (mg/kg/bwt)                                           0.001265                 0.000843                 0.000361                 0.000402
-----------------------------------------------------

[[Page 50143]]


Chronic exposure (mg/kg bwt/day)                                     0.001265                 0.000843                 0.000361                 0.000402
-----------------------------------------------------
%aRfD and %aPAD                                                            NA                       NA                       NA                       NA
-----------------------------------------------------
%cRfD and %cPAD                                                         25.30                    16.87                     7.23                     8.03
-----------------------------------------------------
                                                                        AGGREGATE
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acute exposure (mg/kg bwt/day)                                       0.174865                 0.166243                 0.064221                 0.073462
-----------------------------------------------------
Chronic exposure (mg/kg bwt/day)                                     0.009237                 0.015963                 0.007214                 0.008173
-----------------------------------------------------
%aRfD and %aPAD                                                            NA                       NA                       NA                       NA
-----------------------------------------------------
%cRfD and %cPAD                                                         33.27                    31.99                    14.08                    15.80
--------------------------------------------------------------------------------------------------------------------------------------------------------

     These results indicate the aggregate exposure of dimethomorph (BAS 
550 F), from potential residues in food and drinking water, will not 
exceed EPA's level of concern (100% of RfD). Overall, considering a 
``worst-case'' scenario, we can conclude with reasonable certainty that 
no harm will occur from either acute or chronic aggregate exposure of 
dimethomorph residues in the current and pending commodities.
    3. Non-dietary exposure. Currently, there are no registered 
residential uses for dimethomorph in the United States. Thus, an 
assessment of non-dietary exposure is not relevant to this petition.

D. Cumulative Effects

     There is no information to indicate that any toxic effects 
produced by dimethomorph would be cumulative with those of any other 
chemical. The fungicidal mode of action of dimethomorph is unique; 
dimethomorph inhibits cell wall formation only in Oomycete fungi. The 
result is lysis of the cell wall that kills growing cells and inhibits 
spore formation in mature hyphae. This unique mode of action and 
limited pest spectrum suggest that there is little or no potential for 
cumulative toxic effects in mammals. In addition, the toxicity studies 
submitted to support this petition do not indicate that dimethomorph is 
a particularly toxic compound. No toxic end-points of potential concern 
were identified.

E. Safety Determination

    1. U.S. population. Based on the acute toxicity data, BASF believes 
that dimethomorph does not pose any acute dietary risks. Therefore, a 
calculation of an acute RfD is not needed. The cPAD is 0.1 mg/kg bwt/
day, based on a NOAEL of approximately 10 mg/kg bwt/day (200 ppm) from 
a 2-year dietary toxicity study in rats that demonstrated decreased 
body weight and liver foci in females at 750 ppm. The cPAD is 
calculated using an uncertainty factor of 100. The theoretical maximum 
residue concentration (TMRC) for all commodities covered in this 
petition is estimated at 0.003 mg/kg bwt/day for the general 
population. This represents a dietary exposure to the general 
population of the United States that is 3.0% of the cPAD. The combined 
TMRC for all current and pending dimethomorph tolerances in potatoes, 
tomatoes, grapes, hops, cereal grain commodities, lettuce (head and 
leaf), endive (escarole), radichio, cucurbit vegetables (crop group 9), 
bulb vegetables (crop group 3), and fruiting vegetables (except 
cucurbits) (crop group 8) will utilize less than 10% of the cPAD for 
the general U.S. population. Since EPA generally has no concern for 
exposures below 100 percent of the cPAD, EPA should conclude that there 
is a reasonable certainty that no harm will result from aggregate 
exposure to dimethomorph residues in or on commodities of the cited 
crops.
    2. Infants and children. The TMRC for all commodities covered in 
this petition is minimal. The consumption of residues of dimethomorph 
on commodities associated with this request will use approximately 7.0% 
of the cPAD for children ages 1-6. Moreover, the combined TMRC values 
for all current and pending dimethomorph tolerances will utilize less 
than 10% of the cPAD for each of the subgroups. The results of the 
studies submitted to support this package provide no evidence that 
dimethomorph caused reproductive, developmental or fetotoxic effects. 
No such effects were noted at dose levels that were not maternally 
toxic. The NOAELs observed in the developmental and reproductive 
studies were 6 to 65 times higher than the NOAEL used to establish the 
cPAD. There is no evidence to indicate that children or infants would 
be more sensitive than adults to toxic effects caused by exposure to 
dimethomorph. Therefore, the registrant believes that the results of 
the toxicology and metabolism studies support both the safety of 
dimethomorph to humans based on the intended use as a fungicide on 
domestically produced fruiting vegetables (except cucurbits) (crop 
group 8) and the granting of the requested tolerances.

F. International Tolerances.

     There are no Canadian, Mexican, or Codex maximum residue levels 
established for dimethomorph for the commodities associated with this 
request; consequently, a discussion of international harmonization is 
not relevant.
[FR Doc. 03-20899 Filed 8-19-03; 8:45 am]

BILLING CODE 6560-50-S 

 
 


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