[Federal Register Volume 68, Number 88 (Wednesday, May 7, 2003)]
[Notices]
[Pages 24463-24467]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-11198]


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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2003-0156; FRL-7305-7]


Cyazofamid; 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-2003-0156, must be 
received on or before June 6, 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: Dennis McNeilly, Registration Division 
(7505C), Office of Pesticide Programs, Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone 
number: (703) 308-6742]; 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. 
Potentially affected entities may include, but are not limited to:
    [sbull] Crop production (NAICS 111)
    [sbull] Animal production (NAICS 112)
    [sbull] Food manufacturing (NAICS 311)
    [sbull] 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. EPA Docket. EPA has established an official public docket for 
this action under docket ID number OPP-2003-0156. 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 EPA Internet under the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr/.
     An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA dockets. You may 
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public 
comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Although, not all docket materials may be 
available electronically, you may still access any of the publicly 
available docket materials through the docket facility identified in 
Unit I.B.1. Once in the system, select ``search,'' then key in the 
appropriate docket ID number.
     Certain types of information will not be placed in 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

[[Page 24464]]

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-2003-0156. 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-2003-0156. 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-2003-0156.
    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-2003-0156. Such deliveries are only accepted during the 
docket's normal hours of operation as identified in Unit I.B.1.

D. How Should I Submit CBI To the Agency?

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

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

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

II. What Action is the Agency Taking?

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

List of Subjects

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

    Dated: April 23, 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.

[[Page 24465]]

 ISK Biosciences Corporation

 PP 1F6305

     EPA has received a pesticide petition [1F6305] from ISK 
Biosciences Corporation, 7470 Auburn Road, Suite A, Concord OH 44077, 
proposing, pursuant to section 408(d) of the Federal Food, Drug, and 
Cosmetic Act (FFDCA), 21 U.S.C. 346a(d), to amend 40 CFR part 180 by 
establishing a tolerance for residues of the fungicide cyazofamid, 4-
chloro-2-cyano-N, N-dimethyl-5-(4-methylphenyl)-1H-imidazole-1-
sulfonamide (CA), in or on the raw agricultural commodity (RAC) 
potatoes at 0.01 parts per million (ppm) and cucurbits at 0.1 ppm and 
the fungicide cyazofamid and the metabolite CCIM, 4-chloro-5-(4-
methylphenyl)-1H-imidazole-2-carbonitrile (CA) in or on the RAC 
tomatoes at 0.2 ppm and wine grapes at 1.0 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 plant metabolism studies in potatoes and 
tomatoes, together with the magnitude of the residue studies in 
potatoes, tomatoes and cucurbits, suggest that the tolerance for 
potatoes, tomatoes, and cucurbits should be based only on parent 
cyazofamid. However, magnitude of the residue studies on processed 
tomatoes indicate that both cyazofamid and CCIM are identifiable 
residues in tomato puree and paste. The nature and magnitude of the 
residue studies for potatoes showed that there were no detectable 
residues of cyazofamid or any of its metabolites in the RACs or 
processed commodities. Similar studies on fresh tomatoes indicated that 
the major identifiable and quantifiable residue is cyazofamid. 
Magnitude of the residue studies conducted on cucurbits (cucumber, 
summer squash and melon) also confirmed that the major residue is 
cyazofamid. Nature of the residue studies showed that no single 
identifiable residue represents more than about 7% of the total 
radioactive residue. The nature and magnitude of the residue studies on 
grapes showed that cyazofamid was the major identifiable residue with 
low levels of CCIM. The residue in wine made from cyazofamid treated 
grapes is CCIM. The tolerance expression for potatoes and cucurbits 
will include parent cyazofamid only. The tolerance expression for wine 
grapes and tomatoes will include parent, cyazofamid, and the metabolite 
CCIM.
    2. Analytical method. An analytical enforcement method is available 
for determining cyazofamid plant residues in or on potatoes, cucurbits, 
tomatoes and wine grapes. Samples are chopped in a food chopper and a 
20-g sub-sample is removed for extraction with 100 milliliter (mL) of 
acetonitrile (twice). The combined extracts are partitioned with hexane 
and then are reduced to 10 mL with a rotary evaporator. The sample is 
then partitioned between 100 mL of 2% aqueous sodium sulfate solution 
and 50 mL of methylene chloride (twice). The residue is dissolved and 
passed through a 2 gram (g) Florisil column followed by quantification 
by ultraviolet-high performance liquid chromatography (UV-HPLC).
    3. Magnitude of residues. Residue data from 31 field trails (0- and 
7-day pre-harvest intervals (PHIs)) on cucurbits [11 sites for 
cucumbers, 11 sites for muskmelons and 9 sites for summer squash] 
conducted from 1999-2001 showed that mean cyazofamid residues were 0.02 
ppm for 0-day PHI and <0.01 ppm for 7-day PHI on the RAC commodities. 
The highest mean cyazofamid residue was 0.07 ppm at 0-day PHI on 
muskmelon. The highest 7-day PHI cyazofamid residue was 0.04 ppm on 
cucumbers. At both PHI's CCIM residues were <0.01 ppm except for 3 
samples (2 sites, both 0-day PHI) which were at the 0.01 ppm LOQ. The 
sample with the highest total residue had 0.08 ppm (0.07 ppm cyazofamid 
+ 0.01 ppm CCIM). The studies had a target of 6 applications of 0.071 
lb. of active ingredient per acre (0.42 lb acre (a.i./acre) total) of 
the Cyazofamid 400SC formulation each at 7-day intervals.
     Data from 18 field trials in potatoes conducted in 1999-2000 
showed that no residues of cyazofamid or CCIM were observed in any of 
the RAC commodity at any location (7-day PHI). There were up to 10 
applications of 0.071 lb. of active ingredient per acre (0.70 lb a.i./
acre total) of the Cyazofamid 400SC formulation at 7-day intervals. The 
PHI for most trials was 7-days; however, residue dissipation studies 
with PHIs of 0-, 1-, 3- and 7-days were run at 2 locations. Maximum 
residues of 0.01 ppm of cyazofamid were seen at 0- and 1-day PHIs at 
one location and no residues were found at the other location. The 
results of a processing study in which the final application was at a 
3X application rate showed that for samples taken with a 3-day PHI no 
detectable residues of cyazofamid or CCIM were found in potato flakes, 
chips or wet peels. Therefore, no concentration of residues occurred 
during processing.
     For tomatoes, residues of cyazofamid were determined in the 
treated samples from 35 RAC trials (0- and 7-day PHI) conducted from 
1999-2001. The mean per site residues ranged from non-detected (<0.01 
ppm) to 0.15 ppm cyazofamid. CCIM residues of 0.01-0.02 ppm were found 
in samples from four of the sites. The sample with the maximum residue 
had 0.16 ppm cyazofamid and no detectable CCIM. The studies had a 
target of six applications of 0.071 lb of active ingredient per acre 
(0.42 lb a.i./acre total) of the Cyazofamid 400SC formulation each at 
7-day intervals.
     The results of a tomato processing study in which the final 
application was at a 3X application rate showed that for samples taken 
with a 3-day PHI, cyazofamid was <0.01 ppm in both tomato paste and 
puree. Tomato paste had 0.02 ppm CCIM and tomato puree had 0.01 ppm 
CCIM. Therefore, there is no concentration of residues during tomato 
processing.
     Data from 15 field trials in grapes conducted from 1999-2001 in 
the United States, Argentina, Mexico and Europe showed that mean 
cyazofamid residues ranged from <0.01 to 0.34 ppm and mean CCIM 
residues ranged from < 0.01 to 0.02 ppm in the RAC commodity (21-day 
PHI) following eight applications of 0.081 to 0.089 lb. of active 
ingredient per acre (0.65 to 0.71 lb a.i./acre total) of the Cyazofamid 
25SC formulation each at 10- to 16-day intervals.
     Grapes from six of the sites were processed into must and wine. 
Most samples had cyazofamid residues ranging from 0.01 to 0.09 ppm. The 
CCIM residues in must ranged from <0.01 to 0.01 ppm. Cyazofamid 
residues in wine were all <0.01 ppm. CCIM residues in wine ranged from 
<0.01 ppm to 0.02 ppm.

B. Toxicological Profile

    1. Acute toxicity. Results from a battery of acute toxicity studies 
place technical cyazofamid in Toxicity Category IV for oral 
LD50, inhalation LC50 and dermal and eye 
irritation , and Category III for dermal LD 50. Technical 
cyazofamid is not a dermal sensitizer. In an acute neurotoxicity study, 
no treatment related effects were observed at any dose. The no observed 
effect level (NOEL) was 2,000 milligrams/kilogram (mg/kg) bodyweight 
(bwt).
    2. Genotoxicity. A battery of five tests has been conducted to 
assess the genotoxic potential of technical

[[Page 24466]]

cyazofamid. Assays conducted included in vitro reverse gene mutation 
tests in bacteria and an in vitro forward gene mutation test in a 
mammalian cell system, a chromosomal damage test in mammalian cells, a 
DNA repair test in bacteria, and an in vivo micronucleus test in mice. 
Cyazofamid did not elicit a genotoxic response in any of the studies 
conducted.
    3. Reproductive and developmental toxicity. In a two-generation 
reproductive toxicity study, the only effects observed were body weight 
effects which were observed at 20,000 ppm in dams during gestation and 
lactation and in weanling pups. No reproductive effects were observed. 
The NOEL for reproductive effects was 20,000 ppm (1,338 mg/kg bwt/day). 
The NOEL for parental toxicity was 2,000 ppm (134 mg/kg bwt/day). In a 
rat developmental study, cyazofamid was dosed by gavage from Days 0 to 
19 of gestation. There were no treatment-related effects observed in 
the study. The NOEL for maternal and developmental effects was 1,000 
mg/kg bwt/day. In a rabbit developmental study, pregnant rabbits were 
dosed with cyazofamid by gavage on Days 4 to 28 of gestation. There 
were no treatment-related effects observed in the study. The NOEL for 
maternal and developmental effects was 1,000 mg/kg bwt/day. The 
developmental studies (prenatal developmental studies in rat and rabbit 
and the two generation reproduction study in rat) provided no 
indication of increased sensitivity of rats or rabbits from in utero or 
postnatal exposure to cyazofamid. Cyazofamid is not a developmental or 
reproductive toxicant.
    4. Subchronic toxicity. The oral toxicity of cyazofamid was 
investigated in rats and dogs in 13-week studies. The exposure was by 
dietary administration for the rats and by capsule for the dogs. There 
were no treatment-related effects observed in dogs up to 1,000 mg/kg 
bwt/day which was the highest dose tested. In rats, treated at 5,000 
ppm there was a treatment related increase in kidney and liver weights 
and increased observation of basophilic tubules. The latter was 
observed only in males. The NOEL was 500 ppm which was equivalent to a 
dosage of 29.9 mg/kg bwt/day to males and 33.3 mg/kg bwt/day to 
females.
    5. Chronic toxicity. A combined chronic and oncogenicity study was 
conducted in rats. Cyazofamid was administered continuously for a 
period of 104 weeks to male and female Fischer rats. Cyazofamid was not 
carcinogenic in this study. The NOEL for chronic effects was 500 ppm 
(17 mg/kg bwt/day) based on kidney and liver weight differences and 
increases in urine volume and chloride levels at 5,000 ppm. In a long-
term feeding study, mice were dosed with cyazofamid in the diet for 78 
weeks. No treatment related effects were observed and it was concluded, 
that cyazofamid was not carcinogenic. The NOEL was 7,000 ppm (985 and 
1,203 mg/kg bwt/day for males and females, respectively). In a chronic 
dog study, four groups of six dogs/sex/group received the test material 
via capsule for 52 weeks. No treatment related effects were observed. 
The NOEL was 1,000 mg/kg bwt/day.
    6. Animal metabolism. Studies on the metabolism of cyazofamid in 
animals using radioactive test material have been conducted with 
cyazofamid, labeled with 14C in two positions, the benzene [14C-Bz]- or 
imidazole [14C-Im] position. Absorption is rapid, but the percentage of 
cyazofamid absorbed after an oral dosage decreases as the dosage is 
increased. All absorbed radiocarbon is rapidly eliminated with urinary 
and biliary elimination of radiocarbon nearly complete within 24 hours. 
The metabolic pathway of cyazofamid includes the rapid hydrolysis of 
the dimethylsulfonamide group and the oxidation of the benzyl methyl 
group.
    7. Metabolite toxicology. Comparison of the metabolism of 
cyazofamid by plants and in animals indicates that a number of the 
identified metabolites are common to both plants and animals but 
metabolism in plants is more extensive than in animals. The data 
indicate that the final products of the metabolism of cyazofamid in 
animals and plants represent differences in the extent of metabolism. 
Several of the metabolites resulting from cyazofamid are similar in 
plants and animals and, therefore, have already been evaluated 
toxicologically.
    8. Endocrine disruption. An evaluation of the potential effects on 
the endocrine systems of mammals has not been determined; however, no 
evidence of such effects was reported in subchronic, chronic or 
reproductive toxicology. There was no observed pathological finding of 
the endocrine organs in these studies, and there were no reproductive 
effects at the maximum dose tested of 20,000 ppm. There is no evidence 
at this time that cyazofamid causes endocrine effects.

C. Aggregate Exposure

    1. Dietary exposure. A reference dose (RfD) of 0.17 mg/kg bwt/day 
is proposed for humans, based on the NOEL from the 2 year rat study (17 
mg/kg bwt/day) and dividing by an uncertainty factor of 100. The acute 
NOEL of 100 mg/kg bwt is from the acute neurotoxicity study adjusted 
for oral absorption of 5%. No treatment related effects were observed 
at any dose level.
    i. Food. Tier 1 chronic and acute dietary exposure analyses were 
conducted for cyazofamid in/on cucurbits, potatoes, tomatoes and wine 
grapes to determine the exposure contribution of these commodities to 
the diet and to ascertain the chronic and acute risk potential. The 
estimates were based on proposed tolerance level residues for all 
crops, potato and tomato processing studies, market share assumptions 
of 100% crop treated, and consumption data from the 1994 through 1996 
United States Department of Agriculture (USDA) continuing survey of 
food intake.
     Even using all of the worst case exposure scenarios listed above, 
the Tier 1 chronic dietary exposure estimates resulted in an estimated 
exposure for the U.S. population of 0.000594 mg/kg bwt/day. This 
exposure corresponds to 0.3% of the RfD of 0.17 mg/kg bwt/day. The 
highest exposure estimate was calculated for the children 1-6 years 
population subgroup. This exposure was determined to be 0.000939 mg/kg 
bwt/day (0.6% of the RfD).
     The Tier 1 acute assessment for the U.S. population resulted in a 
margin of exposure (MOE) of 35,789 at the 95th percentile. 
This corresponded to an estimated exposure of 0.002793 mg/kg bwt/day. 
The highest acute exposure estimate (95th percentile) was 
observed in children 1-3 years subpopulation: 0.004580 mg/kg bwt/day. 
This correlates to an MOE of 21,833. It can be concluded that acute or 
long-term dietary exposure to cyazofamid through residues on treated 
cucurbits, potatoes, tomatoes and imported wine grapes should not be of 
cause for concern.
    ii. Drinking water. Since cyazofamid is intended for application 
outdoors to field grown potato, tomato and cucurbits crops, the 
potential exists for parent and or metabolites to reach ground or 
surface water that may be used for drinking water. The calculated 
drinking water levels of comparison (DWLOCs) for chronic exposure for 
adult males, adult females and toddlers were estimated to be 5,929 
parts per billion (ppb), 5,083 ppb, and 1,691 ppb, respectively. The 
calculated DWLOCs for acute exposure for all adults, adult females and 
toddlers were estimated to be 34,902 ppb, 29,923 ppb, and 9,954 ppb, 
respectively. The chronic and acute DWLOC values are well above the 
modeled chronic and acute drinking water estimated concentrations 
(DWECs) of 0.023 ppb (generic expected estimated concentration (GENEEC) 
56-day) and 1.38 ppb (GENEEC

[[Page 24467]]

instantaneous value), respectively. Therefore, there is comfortable 
certainty that no harm will result from combined dietary food and 
water, exposure due to the use of cyazofamid on cucurbits, potatoes and 
tomatoes.
    2. Non-dietary exposure. No petition for registration of cyazofamid 
is being made for either indoor or outdoor residential use. Non-
occupational exposure of cyazofamid to the general population is, 
therefore, not expected and is not considered in aggregate exposure 
estimates.

D. Cumulative Effects

     Cyazofamid is a cyanoimidazole fungicide. Since there are no other 
members of this class of fungicides, it is considered unlikely that 
cyazofamid would have a common mechanism of toxicity with any other 
pesticide in use at this time.

E. Safety Determination

    1. U.S. population. Dietary and occupational exposure will be the 
major routes of exposure to the U.S. population. Ample margins of 
safety have been demonstrated for both situations. For the U.S. 
population, the chronic dietary exposure to cyazofamid is 0.000594 mg/
kg bwt/day, which utilizes 0.3% of the RfD for the overall U.S. 
population, assuming 100% of the crops are treated. The acute dietary 
exposure to the U.S. population is 0.002793 mg/kg bwt/day 
(95th percentile) resulting in a MOE of 35,789.
     Using only pesticide handlers exposure data base (PHED) data 
levels A and B (those with a high level of confidence), MOE for 
occupational exposure is 5,195 for mixer/loaders, and 5,884 for aerial 
applicators. Based on the completeness and reliability of the toxicity 
data and the conservative exposure assessments, there is a reasonable 
certainty that no harm will result from the aggregate exposure of 
residues of cyazofamid including all anticipated dietary exposure and 
all other non-occupational exposures.
    2. Infants and children. Chronic dietary exposure of the most 
highly exposed subgroup in the population, children 1-6, is 0.000939 
mg/kg bwt/day or 0.6% of the RfD. The acute dietary exposure of the 
most exposed subgroup, children 1-3, is 0.00458 mg/kg bwt/day. This 
correlates to an MOE of 21,833.
     There are no residential uses of cyazofamid. Based on the 
completeness and reliability of the toxicity data, the lack of 
toxicological endpoints of special concern, the lack of any indication 
of greater sensitivity of children, and the conservative exposure 
assessment; there is a reasonable certainty that no harm will result to 
infants and children from the aggregate exposure to residues of 
cyazofamid from all anticipated sources of dietary and non-occupational 
exposure. Accordingly, there is no need to apply an additional safety 
factor for infants and children.

F. International Tolerances

     There are presently no Codex maximum residue limits established 
for residues of cyazofamid on any crop.
[FR Doc. 03-11198 Filed 5-6-03; 8:45 am]
BILLING CODE 6560-50-S