[Federal Register Volume 66, Number 225 (Wednesday, November 21, 2001)]
[Notices]
[Pages 58477-58481]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-28739]


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ENVIRONMENTAL PROTECTION AGENCY

[PF-1042; FRL-6799-1]


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 control number PF-1042, must be 
received on or before Decmber 21, 2001.

ADDRESSES:  Comments may be submitted by mail, electronically, or in 
person. Please follow the detailed instructions for each method as 
provided in Unit I.C. of the SUPPLEMENTARY INFORMATION. To ensure 
proper receipt by EPA, it is imperative that you identify docket 
control number PF-1042 in the subject line on the first page of your 
response.

FOR FURTHER INFORMATION CONTACT:  By mail: Rita Kumar, Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460; 
telephone number: (703) 308-8391; e-mail address: [email protected].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be affected by this action if you are an agricultural 
producer, food manufacturer or pesticide manufacturer. Potentially 
affected categories and entities may include, but are not limited to:

------------------------------------------------------------------------
                                                          Examples of
           Categories                 NAICS codes         potentially
                                                       affected entities
------------------------------------------------------------------------
Industry                          111                 Crop production
                                  112                 Animal production
                                  311                 Food manufacturing
                                  32532               Pesticide
                                                       manufacturing
------------------------------------------------------------------------

    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 the table could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether or not this action might apply to certain entities. If you have 
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 Additional Information, Including Copies of this 
Document and Other Related Documents?

    1. Electronically. You may obtain electronic copies of this 
document, and certain other related documents that might be available 
electronically, from the EPA Internet Home Page at http://www.epa.gov/. 
To access this document, on the Home Page select ``Laws and 
Regulations,'' ``Regulations and Proposed Rules,'' and then look up the 
entry for this document under the ``Federal Register--Environmental 
Documents.'' You can also go directly to the Federal Register listings 
at http://www.epa.gov/fedrgstr/.
    2. In person. The Agency has established an official record for 
this action under docket control number PF-1042. The official record 
consists of the documents specifically referenced in this action, any 
public comments received during an applicable comment period, and other 
information related to this action, including any information claimed 
as confidential business information (CBI). This official record 
includes the documents that are physically located in the docket, as 
well as the documents that are referenced in those documents. The 
public version of the official record does not include any information 
claimed as CBI. The public version of the official record, which 
includes printed, paper versions of any electronic comments submitted 
during an applicable comment period, is available for inspection in the 
Public Information and Records Integrity Branch (PIRIB), Rm. 119, 
Crystal Mall #2, 1921 Jefferson Davis Highway, Arlington, VA, from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.

C. How and to Whom Do I Submit Comments?

    You may submit comments through the mail, in person, or 
electronically. To ensure proper receipt by EPA, it is imperative that 
you identify docket control number PF-1042 in the subject line on the 
first page of your response.
    1. By mail. Submit your comments to: Public Information and Records 
Integrity Branch (PIRIB), Information Resources and Services Division 
(7502C), Office of Pesticide Programs (OPP), Environmental Protection 
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
    2. In person or by courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Information Resources 
and Services Division (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, Rm. 119, Crystal Mall #2, 1921 
Jefferson Davis Highway, Arlington, VA. The PIRIB is open from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.
    3. Electronically. You may submit your comments electronically by 
e-mail to: [email protected], or you can submit a computer disk as 
described above. Do not submit any information electronically that you 
consider to be

[[Page 58478]]

CBI. Avoid the use of special characters and any form of encryption. 
Electronic submissions will be accepted in Wordperfect 6.1/8.0 or ASCII 
file format. All comments in electronic form must be identified by 
docket control number PF-1042. Electronic comments may also be filed 
online at many Federal Depository Libraries.

D. How Should I Handle CBI That I Want to Submit to the Agency?

    Do not submit any information electronically that you consider to 
be CBI. You may claim information that you submit to EPA in response to 
this document as CBI by marking any part or all of that information as 
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 version of the 
official record. Information not marked confidential will be included 
in the public version of the official record without prior notice. If 
you have any questions about CBI or the procedures for claiming CBI, 
please consult the person identified 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 
control 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 Comestic Act (FFDCA), 21 U.S.C. 346a. 
EPA has determined that this petition contains data or information 
regarding the elements set forth in 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: October 24, 2001.
Peter Caulkins,
Acting Director, Registration Division, Office of Pesticide Programs.

Summary of Petition

    The petitioner summary of the pesticide petition is printed below 
as required by section 408(d)(3) of the FFDCA. The summary of the 
petition was prepared by the petitioner and represents the view of the 
petitioner. EPA is publishing the petition summary verbatim without 
editing it in any way. 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.

ISK Biosciences Corporation

6F4662, 6F4701, 6F4755, 6E4773, 5E4474

    EPA has received pesticide petitions (6F4662, 6F4701, 6F4755, 
6E4773, 5E4474) 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 
nematicide, fosthiazate, ((RS)-S-sec-butyl O-ethyl 2-oxo-1,3-
thiazolidin-3-ylphosphonothioate) and its metabolite ASC-67131 (BESoP, 
(RS)-S-sec-butyl O-ethyl N-2(methylsulfonyl)ethyl 
phosphoramidothioate)] in or on the raw agricultural commodities 
tomatoes and peanuts at 0.02 parts per million (ppm), potatoes at 0.03 
ppm, and import tolerances on bananas and green coffee beans at 0.05 
parts per million (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 
supports granting of the petitions. Additional data may be needed 
before EPA rules on the petitions.

A. Residue Chemistry

    1. Plant metabolism. Metabolism studies were conducted on tomatoes, 
potatoes, and peaches. Fosthiazate is extensively metabolized in plants 
by a combination of hydrolytic and oxidative processes that convert the 
parent to small polar fragments. Residues in mature edible plant parts 
consist of polar S-butyl group degradates and radioactivity that is 
reincorporated into plant natural products from thiazolidinone ring 
carbon atoms. Analyses of leaf and stem tissues established the 
identity of intermediate metabolites in the pathway.
    2.  Analytical method. A gas chromatographic analytical method 
using a flame photoionization detector in the phosphorus mode has been 
validated for enforcement purposes. The limit of detection for both 
fosthiazate and its metabolite ASC-67131 is 0.01 ppm for all crops 
(tomatoes, potatoes, peanuts, bananas, green coffee beans and roasted 
coffee.) The limit of detection for both parent and metabolite in 
instant coffee is 0.05 ppm.
    3. Magnitude of residues--i. Tomatoes. The application rate of 4-6 
lbs of the active ingredient per acre (a.i./acre) was applied and 
tomatoes harvested from 80-147 days after application in 6 of 15 test 
sites. No detectable residues of either parent or the metabolite ASC-
67131 were found (LOD = 0.01 ppm). The proposed maximum label rate is 
4.5 lb a.i./acre.
    ii. Potatoes. The application rate of 4-6 lb of the a.i. was 
applied and potatoes harvested from 82-179 days after application in 11 
test sites. The maximum fosthiazate residue found was 0.02 ppm at 4 lb 
ai/acre and 0.07 ppm at 6 lb ai/acre, while no detectable residues of 
the metabolite ASC-67131 were found. The proposed maximum label rate is 
4.5 lb a.i./acre.
    iii. Peanuts. The application rate of 4-6 lb of the a.i./acre was 
applied and peanuts harvested from 99-175 days after application in 16 
test sites. No detectable residues of either parent or the metabolite 
ASC-67131 were found (LOD = 0.01 ppm) in either peanut nutmeat or hay. 
The proposed maximum label rate is 4.0 lb a.i./acre.
    iv. Bananas. The maximum application rate of 2 grams of the active

[[Page 58479]]

ingredient per mat was applied and bananas harvested from 0-126 days 
after application in 6 of 15 test sites. The maximum fosthiazate 
residue found was 0.03 ppm, while no detectable residues of the 
metabolite ASC-67131 were found.
    v. Coffee. The maximum application rate of 2 grams of the active 
ingredient per plant was applied 60 days prior to harvest in eight test 
sites. The maximum fosthiazate residue found was 0.02 ppm, while no 
detectable residues of the metabolite ASC-67131 were found. After a 
single application of fosthiazate at 10 grams per plant 31 days before 
harvest, roasted coffee beans and instant coffee were analyzed. No 
residues were found above the limit of detection of the method in the 
processed fractions.

B. Toxicological Profile

    1. Acute toxicity. Results of the acute toxicity testing are 
described below.

------------------------------------------------------------------------
 
------------------------------------------------------------------------
Oral toxicity to rats (suspended in corn   LD50 is 73 mg/kg bwt (males)
 oil)                                       57 mg/kg bwt (females)
Oral toxicity to rats (solution in water)  LD50 is 49 mg/kg bwt (males)
                                            28 mg/kg bwt (females)
Dermal toxicity to rats                    LD50 is 2,372 mg/kg bwt
                                            (males) 853 mg/kg bwt
                                            (females)
Inhalation toxicity to rats (4-hour)       LC50 is 0.83 milligrams per
 exposure                                   Liter (mg/L) (males) 0.56 mg/
                                            L (females)
Dermal irritation, rabbits                 No irritation
Eye irritation, rabbits no wash            Irritation reversible in 1
                                            week, mortality
Eye irritation, rabbits with wash          Irritation, reversible in 1
                                            week, no mortality
Skin sensitization Magnusson-Klingman      Positive
Acute delayed neurotoxicity: hen           Negative
Acute cholinesterase no observed adverse   No inhibition of
 effect level (NOAEL): rat                  cholinesterase activity at 4
                                            mg/kg bwt in erythrocyte or
                                            brain
Acute neurotoxicity: rat                   NOEL for functional
                                            observation battery, motor
                                            activity and
                                            neuropathology:10 mg/kg bwt
------------------------------------------------------------------------


    2. Genotoxicty. A battery of tests has been conducted to assess the 
genotoxic potential of technical fosthiazate. Assays conducted included 
in vitro gene mutation tests in bacteria and mammalian cell systems, a 
chromosomal aberration test in mammalian cells, a DNA repair test in 
bacteria and an in vivo micronucleus test in mice. Technical 
fosthiazate did not elicit a genotoxic response in any of the studies 
conducted.
    3. Reproductive and developmental toxicity. In a developmental 
study with rats at 0, 3, 5, and 10 mg/kg bwt/day the NOAEL for maternal 
toxicity based on the maternal body weight reduction was 5 mg/kg bwt/
day. The NOAEL for developmental effects was 10 mg/kg bw/day. Technical 
fosthiazate did not cause developmental toxicity in rats.
    A developmental study with rabbits was conducted at dosages 0, 0.5, 
1.0, 1.5 or 2.0 mg/kg bwt/day. The NOAEL for maternal effects in this 
study was 2.0 mg/kg bwt/day. This dosage was considered very close to a 
maternally toxic dose because, in the preliminary study, maternal 
lethality was observed at 5 mg/kg bwt/day and there were isolated 
incidences of maternal animals in extremis at 2.0 and 2.5 mg/kg bwt/
day. The NOAEL for developmental effects was considered 2.0 mg/kg bwt/
day. Technical fosthiazate was not teratogenic in rabbits.
    In a two generation reproduction study, technical fosthiazate was 
administered via the diet at concentrations of 0, 3.2, 10.7, 32.2 or 
107.2 ppm to CD rats. The group receiving 107.2 ppm was terminated at 
weaning of the F0 generation due to poor survival of offspring. In the 
first generation, there was a statistically significant increase in the 
length of gestation at 107.2 ppm. The difference was not significant at 
any other dosage or in the second generation. Viability indices and 
body weight gain of F1 offspring were reduced at 32.2 ppm and higher. 
These effects were particularly marked at 107.2 ppm. No effects on pup 
viability were observed in the second generation. The dietary 
concentration of 10.7 ppm which was equivalent to 0.86 mg/kg bwt/day 
was the NOAEL for the effects on pup survivability and pup body weight 
observed in this study.
    4. Subchronic toxicity. In a 13-week feeding study in rats with a 
recovery phase, Sprague-Dawley rats received technical fosthiazate via 
the diet at concentrations of 0, 1.07, 10.7, 53.6 or 429 ppm for 13 
weeks. The NOAEL for the study was 10.7 ppm technical fosthiazate in 
the diet based on inhibition of brain cholinesterase activity and 
adrenal effects. The effects were reversible.
    In a 13-week study, beagle dogs received technical fosthiazate at 
dosages of 0, 0.054, 0.11, 0.54, or 5.4 mg/kg bwt/day daily. The NOAEL 
for adrenal effects and cholinesterase inhibition in the erythrocyte 
and brain, was 0.54 mg/kg bwt/day.
    A 90-day dietary neurotoxicity study in rats was conducted at doses 
of 0, 0.07, 0.56 and 2.4 mg/kg bwt/day and of 0, 0.08, 0.57 and 2.5 mg/
kg bwt/day to males and females, respectively. In spite of lower 
cholinesterase levels, no clinical signs of cholinesterase inhibition, 
no differences in the functional observational battery, in mean 
forelimb and hind limb grip strengths, mean foot-spread, mean motor 
activity values or neuropathology were observed in the animals 
administered 2.5 mg/kg bwt/day of technical fosthiazate via the diet. 
The NOAEL for inhibition of cholinesterase activity in the brain was 
0.56 mg/kg bwt/day.
    In a 21-day dermal toxicity study in rats, at dosages of 0, 0.5, 
2.5, 25, or 250 mg/kg bwt/day by occluded dermal application for 21 
days, the NOAEL in terms of cholinesterase inhibition in the brain was 
2.5 mg/kg bwt/day.
    5. Chronic toxicity. In a 2-year feeding study in rats, technical 
fosthiazate was administered to CD rats at dietary concentrations of 0, 
1.07, 10.7, 53.6, or 214 ppm. Treatment did not change the incidence of 
any neoplasm. The NOAEL for the study which was based on adrenal 
effects and cholinesterase inhibition in the brain, was 10.7 ppm in the 
diet which was equivalent to 0.41 mg/kg bwt/day.
    In the mouse oncogenicity study, technical fosthiazate was 
administered for a period of 102 weeks to CD-1 mice at concentrations 
of 0, 10.7, 32.2, 107, or 322 ppm. There was no evidence of oncogenic 
potential. The NOAEL of technical fosthiazate in CD-1 mice was 
considered to be 32.2 ppm which was equivalent to 3.32 mg/kg bwt/day.
    A 12-month oral chronic toxicity study was conducted in beagle dogs 
at dose levels of 0, 0.05, 0.1, 0.5 and 5.0 mg/kg bwt/day. No 
treatment-related change in brain cholinesterase activity was noted. 
The NOAEL which was based upon adrenal effects was 0.5 mg/kg bwt/day.
    Comparison of the toxicology data from subchronic (90 days 
exposure) and chronic studies showed no major differences in effects or 
in effect levels. Therefore, a single reference dose (RfD) for 
subchronic and chronic exposure is proposed.
    6. RfD. Fosthiazate is nonteratogenic, nononcogenic, and 
nonmutagenic and there is no evidence of bioaccumulation. Inhibition of 
cholinesterase activity is considered the primary treatment-related 
effect from fosthiazate. Although cholinesterase activity was measured 
in plasma, erythrocytes and brain in the

[[Page 58480]]

toxicity studies with fosthiazate, the values from the brain are 
considered the most relevant for assessing adverse effects. For 
cholinesterase activity, only data for inhibition of activity in the 
brain will therefore be included in the selection of a NOAEL for the 
RfD. In addition to inhibition of cholinesterase activity, fosthiazate 
treatment was associated with other effects.
    The lowest NOAEL value was 0.41 mg/kg bwt/day for the inhibition of 
brain cholinesterase activity from the 2-year feeding study in rats. In 
that study, rats were fed a constant dietary concentration of 
fosthiazate. The NOAEL for inhibition of brain cholinesterase activity 
was 10.7 ppm in the diet for both males and females. Since relative 
food consumption is a little lower in males than females, the compound 
consumption was a little lower in males. Since females have been shown 
to be more sensitive to the effects of fosthiazate than males, and 
NOAEL were observed in the female group fed a diet containing 10.7 ppm 
which gave a dose of 0.54 mg/kg bwt/day, the conclusion could be made 
that 0.54 mg/kg bwt/day would be an appropriate NOAEL. The more 
conservative value of 0.41 mg/kg bwt/day will be proposed to add to the 
certainty of no adverse effects. The standard safety factor of 100 will 
be applied to the conservative NOAEL of 0.41 mg/kg bwt/day to give a 
proposed RfD of 0.0041 mg/kg bwt/day.
    7. Animal metabolism. Fosthiazate is extensively metabolized in 
rats by a combination of hydrolytic and oxidative processes that 
rapidly convert the parent molecule to small fragments, including 
CO2. The carbon atoms of the thiazolidinone ring appear to 
be reincorporated into tissues based on the levels found in carcasses 
at termination. Extensive conjugation via the glutathione pathway 
appears to occur.
    8. Metabolite toxicology. Comparison of the metabolism of 
fosthiazate 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. There are, 
however, no metabolites of toxicological concern in plants that do not 
appear in animal studies.
    9. Endocrine disruption. Although subtle histological changes were 
observed in the ovary and adrenals which are organs with endocrine 
function, there were no treatment-related effects associated with 
fosthiazate treatment which are indicative of an effect on endocrine 
function. Since the histological changes in the adrenals and ovaries 
were observed only at dosages which also inhibited cholinesterase 
activity, it is considered possible that the changes were physiological 
adaptions secondary to inhibition of cholinesterase activity. There 
were no other effects observed in the subchronic or chronic studies, 
such as changes to the uterus or mammary tissue or changes in urine 
production which might indicate a change in physiology related to the 
ovarian or adrenal changes.
    In the reproduction study with fosthiazate, fertility and gestation 
indices were unaffected by fosthiazate even when administered at 
dietary concentrations which would result in severe inhibition of 
cholinesterase activity. At those high dietary concentrations (107.2 
ppm) the only treatment-related difference in reproductive effect was a 
statistically significant increase in length of gestation. It is 
considered that the effect on gestation could have been secondary to 
maternal toxicity. The difference was not significant at any other 
dosage in the first or second generation.
    From the reproduction study, reproductive capacity was unaffected 
by treatment; ovarian effects were not observed; and adrenal effects 
were observed only in groups administered 107.2 ppm.
    The conclusion can be drawn that no effects on the endocrine system 
would be expected below the threshold for cholinesterase inhibition. 
Therefore, a NOAEL set for cholinesterase inhibition should also cover 
any other effects.

C. Aggregate Exposure

    1. Dietary exposure--i. Food. For purposes of assessing the 
potential dietary exposure, EPA initially estimates exposure using the 
tolerance (i.e., 0.02 ppm on tomatoes and peanuts, 0.03 ppm on 
potatoes, 0.05 ppm on bananas and whole green coffee beans) as a worst 
case scenario. The potential exposure is obtained by multiplying the 
tolerance level residues by the consumption data which estimates the 
amount of treated products consumed by various population subgroups. In 
chronic analyses, the average consumption for all individuals in a 
population subgroup is used, while in acute analyses only consumers of 
treated commodities are included. While both potato and peanut 
fractions are fed to animals, metabolism studies show that residues are 
incorporated into natural products, and thus there is no exposure to 
residues of toxicological concern through secondary residues in meat, 
milk and eggs.
    ii. Drinking water. The potential for residues of fosthiazate to 
occur in tap water, non-tap water, and water in commercially prepared 
food was also evaluated. Four field dissipation studies were conducted 
with fosthiazate in California, Georgia, North Carolina and Washington 
(Doc. # 3931-95-EF-000). These studies clearly demonstrate that 
fosthiazate and its degradates do not leach under field conditions, and 
that the DT90 of the parent compound ranged from 48-92 days. It is 
therefore reasonable to conclude that the potential for fosthiazate to 
contaminate ground water is extremely low. As fosthiazate will be 
incorporated into the soil after application, no significant runoff or 
spray drift is expected. Therefore, contamination of surface water is 
highly unlikely. Additionally for bananas and coffee, the proposed 
tolerance of fosthiazate is for import commodities only. Due to these 
factors, residues of fosthiazate are not expected in drinking water.
    2. Non-dietary exposure. Since there are no domestic uses (home/
garden) for fosthiazate, there are no non-occupational exposures.

D. Cumulative Effects

    Fosthiazate is an organophosphate, with the most sensitive 
indicator of toxicity being inhibition of cholinesterase after both 
short- and long-term administration. While the exact mechanism for this 
effect may or may not be identical to other organophosphates, in the 
case of the present petitions, this effect is considered to be 
insignificant. This is due primarily to the extremely low exposure to 
the U.S. population from the proposed uses of fosthiazate. The 
incremental increase in exposure to organophosphates from the addition 
of fosthiazate is extremely small. For example, the highest exposed 
population subgroups from chronic exposure to residues in/on tomatoes, 
potatoes and peanuts are children 1-6 yrs with an estimated chronic 
exposure of 0.000132 mg/kg bwt/day, which represents 3.2% of the RfD. 
The highest exposed population subgroup from chronic exposure to 
residues in/on bananas is non-nursing infants 1 year old with an 
estimated chronic exposure of 0.000045 mg/kg bwt/day, which represents 
1.1% of the RfD. The highest exposed population subgroup from chronic 
exposure to residues in/on coffee are seniors (55+), females (20+) and 
males (20+) with 0.000002 mg/kg bwt/day, which represents an 
insignificant portion of the RfD. When all crops, are included in the 
assessment estimated chronic exposure for children 1-6 yrs increases to 
0.000173 mg/kg bwt/day, which represents 4.2% of the

[[Page 58481]]

RfD. This is particularly relevant in that this assessment assumed 
tolerance level residues for all crops (0.02 ppm for tomatoes and 
peanuts, 0.03 ppm for potatoes and 0.05 ppm for bananas and coffee). 
Indeed, when anticipated residues are used estimated exposure is less 
than 2% of the RfD for all population groups.
    A similar situation applies to acute exposure (and risk) from the 
proposed uses. For tomatoes, potatoes and peanuts, the highest exposed 
subgroup is all infants 1 year old, with an acute exposure of 0.000479 
mg/kg bwt/day at the 95th percentile for consumers only. This results 
in a MOE of 8,300, which exceeds the traditional level considered to 
provide adequate protection by nearly two orders of magnitude. When 
residues on bananas and coffee beans are included in the assessment, 
children 1-6 yrs have an estimated acute exposure at the 95th 
percentile of 0.000588 mg/kg bwt/day, which results in an MOE of 6,800. 
Again, when anticipated residues, as calculated for acute exposure 
(i.e., the highest field trial residue), are used in the assessment for 
all the proposed crops, the highest exposure is only 0.000456 mg/kg 
bwt/day at the 95th percentile, with an MOE of 8,700 for all infants 
(consumers only). Indeed MOE's at the 99.9th percentile of exposure are 
far higher than generally is considered to be safe by the agency for 
all population subgroups.

E. Safety Determination

    1. U.S. population. Using the conservative exposure assumptions and 
the proposed RfD and acute NOEL described above, dietary exposure was 
calculated.
    As discussed above, even under the ''worst-case`` chronic exposure 
scenario, a very small portion of the RfD was used. When anticipated 
residues for tomatoes, potatoes and peanuts are used in the chronic 
dietary exposure assessment, the estimated exposure is 0.000068 mg/kg 
bwt/day, for the total U.S. population (or 1.7% of the RfD). When 
bananas and coffee beans are included in the assessment, the estimated 
exposure is 0.000083 mg/kg bwt/day for the total U.S. population (or 
2.0% of the RfD).
    The acute exposure estimates clearly indicate that exposures 
provide adequate MOEs at the 95th percentile of exposure. The U.S. 
population has an estimated 95th percentile exposure value of 0.000246 
mg/kg bwt/day, equivalent to an MOE of 16,000 for tomatoes, potatoes 
and peanuts. When bananas and coffee are included in the assessment, 
the estimated 95th percentile exposure for the total U.S. population is 
0.000279 mg/kg bwt/day, which results in an MOE of 14,000. These values 
are more than 2 orders of magnitude higher than a level considered to 
provide adequate protection. The exposure estimate for fosthiazate when 
highest field trial residue is used is 0.000187 mg/kg bwt/day, 
representing an MOE of 21,000, including all crops. Therefore, since 
there are no other avenues of exposure (see aggregate exposure section 
of this document) ISK Biosciences Corporation concludes that there is a 
reasonable certainty that no harm will result from aggregate exposure 
to fosthiazate residues from use on tomatoes, potatoes, peanuts, 
bananas and coffee.
    2. Infants and children. In assessing the potential for additional 
sensitivity of infants and children to residues of fosthiazate, data 
from developmental toxicity studies and other appropriate studies are 
considered. ISK Biosciences Corporation calculates that children 1-6 
(the highest exposed subgroup) have an estimated chronic dietary 
exposure of 0.000132 mg/kg bwt/day, which represents only 3.2% of the 
RfD using worst case assumptions. When bananas and coffee beans are 
included, these estimates are 0.000173 mg/kg bwt/day and 4.2% of the 
RfD for children 1-6. When anticipated residues are used in calculating 
chronic dietary exposure, only 1.1% of the RfD is consumed for this 
population subgroup and 1.3% of the RfD after bananas and coffee are 
included in the assessment. Acute exposure estimates similarly show no 
concern as all infants 1 year of age (the highest exposed subgroup) 
have MOEs of 8,300 even when using worst case assumptions. When bananas 
and coffee are included in the assessment, children 1-6 years (the 
highest exposed subgroup) have an MOE of 6,800. Therefore, since there 
are no other avenues of exposure other than dietary, there is 
reasonable certainty that no harm will result to infants and children 
from aggregate exposure to fosthiazate from use on tomatoes, potatoes, 
peanuts, bananas and coffee.

F. International Tolerances

    There are no Codex maximum residue levels established for residues 
of fosthiazate.

[FR Doc. 01-28739 Filed 11-20-01; 8:45 am]
BILLING CODE 6560-50-S