[Federal Register Volume 62, Number 185 (Wednesday, September 24, 1997)]
[Notices]
[Pages 49983-49986]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-25338]


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ENVIRONMENTAL PROTECTION AGENCY

[PF-761; FRL-5740-9]


Yoshitomi Fine Chemicals Ltd.; Pesticide Tolerance Petition 
Filing

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 tolerances for residues of 4,5-
Dichloro-1,2-Dithiol-3-one (CASRN 1192-52-5) in or on paper and 
paperboard.

DATES: Comments, identified by the docket control number PF-761, must 
be received on or before October 24, 1997.
ADDRESSES: By mail submit written comments to: Information and Records 
Integrity Branch, Public Information and Services Divison (7506C), 
Office of Pesticides Programs, Environmental Protection Agency, 401 M 
St., SW., Washington, DC 20460. In person bring comments to: Rm. 1132, 
CM #2, 1921 Jefferson Davis Highway, Arlington, VA.
    Comments and data may also be submitted electronically by following 
the instructions under ``SUPPLEMENTARY INFORMATION.'' No confidential 
business information should be submitted through e-mail.
    Information submitted as a comment concerning this document may be 
claimed confidential by marking any part or all of that information as 
``Confidential Business Information'' (CBI). CBI should not be 
submitted through e-mail. Information marked as CBI will not be 
disclosed except in accordance with procedures set forth in 40 CFR part 
2. A copy of the comment that does not contain CBI must be submitted 
for inclusion in the public record. Information not marked confidential 
may be disclosed publicly by EPA without prior notice. All written 
comments will be available for public inspection in Rm. 1132 at the 
address given above, from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays.

FOR FURTHER INFORMATION CONTACT: By mail: Portia Jenkins, Acting 
Product Manager (34), Antimicrobials Division (7510C), Office of 
Pesticide Programs, Environmental Protection Agency, 401 M St., SW., 
Washington, DC 20460. Office location and telephone number: Rm. 6C, 
Crystal Plaza #1, 2800 Crystal Drive, Arlington, VA, (703) 308-6230; e-
mail: <a href="/cdn-cgi/l/email-protection#5d3738333634332e732d322f29343c1d382d3c303c343173382d3c733a322b"><span class="__cf_email__" data-cfemail="4f252a212426213c613f203d3b262e0f2a3f2e222e2623612a3f2e61282039">[email protected]</span></a>.

SUPPLEMENTARY INFORMATION: EPA has received a pesticide petition ((PP) 
7F4902) from Yoshitomi Fine Chemicals, Ltd., 6-9, Hiranomachi 2-chome, 
Chuo-ku, Osaka, 541, Japan, 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 185 ``Tolerances for Pesticides in Food'' by establishing 
Subpart D ``Tolerance Exemptions for Pesticides in Foods'' and 
promulgating therein section 185.9000 establishing a tolerance 
exemption for residues of the slimicide 4,5-Dichloro-1,2-Dithiol-3-one 
(CASRN 1192-52-5) in or on paper and paperboard resulting from its 
addition to pulp and paper mill process water to control slime forming 
organisms. EPA has determined that the 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 supports granting of the 
petition. Additional data may be needed before EPA rules on the 
petition.
    The official record for this notice of filing, as well as the 
public version, has been established for this notice of filing under 
docket control number [PF-761] (including comments and data submitted 
electronically as described below). A public version of this record, 
including printed, paper versions of electronic comments, which does 
not include any information claimed as CBI, is available for inspection 
from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal 
holidays. The official record is located at the address in 
``ADDRESSES''.
    Electronic comments can be sent directly to EPA at:
    <a href="/cdn-cgi/l/email-protection#6c031c1c4108030f0709182c091c0d010d050042091c0d420b031a"><span class="__cf_email__" data-cfemail="157a656538717a767e70615570657478747c793b7065743b727a63">[email protected]</span></a>


    Electronic comments must be submitted as an ASCII file avoiding the 
use of special characters and any form of encryption. Comment and data 
will also be accepted on disks in Wordperfect 5.1 file format or ASCII 
file format. All comments and data in electronic form must be 
identified by the docket number (PF-761) and appropriate petition 
number. Electronic comments on this notice may be filed online at many 
Federal Depository Libraries.

List of Subjects

    Environmental protection, Administrative practice and procedure, 
Paper and paperboard, Slimicides, Pesticides and pests, Reporting and 
recordkeeping requirements.

    Dated: September 16, 1997.

Frank Sanders,

Director, Antimicrobials Division, Office of Pesticide Programs.

Summary of Petition

    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 represent the views 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.

Yoshitomi Fine Chemicals, Ltd.

A. Residue Chemistry

    This petition is not for residues in or on raw agricultural 
commodities. It is for residues in or on food contact paper or 
paperboard. Accordingly, the residue chemistry data submitted are 
solely for the residues remaining in food contact paper and paperboard 
when the subject slimicide (4,5-Dichloro-1,2-Dithiol-3-one, CASRN 1192-
52-5, hereafter referred to as RYH-86) is used in pulp and paper mill 
process water to control slime forming organisms.
    1. Residues in paper and paperboard. GC-MS-SIM analysis of 
approximately 30 paper and paperboard samples manufactured in a 
papermill which used RYH-86 amended slurry water revealed no RYH-86 
detectable with a detection limit of 100 <greek-m>g/kilograms (Kg) of 
paper (i.e., 100 parts per billion (ppb)). Extraction of such samples 
with

[[Page 49984]]

food simulating solvents (FSL's), using standard FDA methods for 
determining food additive extractives from food-contact materials which 
allowed for the equilibration of RYH-86 between the paper and 
paperboard samples and the FSL's for 10-days, revealed no RYH-86 
migration into FSL's at detection limits of 10 <greek-m>g/Kg for 
aqueous FSL's and 100 <greek-m>g/Kg for fatty FSL's (using the same GC-
MS-SIM method for analysis).
    2. Analytical method. This is a tolerance exemption petition and, 
accordingly, no enforcement analytical method is proposed.

B. Toxicological Profile

    1. Acute toxicity. Technical RYH-86 (99.8% active ingredient) is 
moderately toxic by the oral route, with acute oral LD<INF>50</INF> of 
350 milligrams/kilograms (mg/kg) in the male rat and 372 mg/kg in the 
female rat (MRID 41562401). Technical RYH-86 is practically nontoxic by 
dermal application (acute dermal LD<INF>50</INF> > 5,000 mg/kg) but was 
quite irritant to the skin (severe skin irritation and dermal necrosis 
but no mortalities were observed) in an acute dermal toxicity and 
irritation study (MRIDs 41531114 & 41562402). The acute inhalation 
toxicity of RYH-86 was waived by EPA during review of the registration 
for RYH-86 Slimicide (EPA Reg. No. 63898-1) due to its being applied 
only by injection into process water and the resulting lack of 
significant inhalation exposure potential. Guideline 81-4 and 81-5 
primary eye and skin irritation studies for RYH-86 manufacturing use 
product (about 50% RYH-86) showed it to produce severe ocular damage 
and severe skin irritation (MRIDs 41531115 & 41531116). In these same 
studies, technical RYH-86 was a severe eye irritant and a moderate skin 
irritant. Tested at 1% solution (to minimize irritancy effects) RYH-86 
was not a dermal sensitizer (MRID 41531117).
    2. Subchronic toxicity. The evaluation of the subchronic toxicity 
of RYH-86 has been carried out in 2 separate studies which, together 
with a bridging analysis of both, constitute one 3-volume data set 
which was previously reviewed by EPA during the registration review for 
RYH-86 Slimicide (EPA Reg. No. 63898-1: MRIDs 41531118, 41531119, & 
41531120). In these studies, one study used relatively high doses of 
RYH-86 and the other used lower doses. The principal effect of note in 
these studies was gastrointestinal irritation exhibiting as a 
thickening of the gastric mucosa and, at sufficiently high dose, 
ulceration. The No Observed Effects Level (NOEL) for these effects was 
3.8 mg/Kg/day and the Lowest Observed Effects Level (LOEL) was 5.0 mg/
Kg/day. Other effects seen included: an increase in relative renal 
weight in males only (LOEL 5.0 mg/Kg/day, NOEL 3.8 mg/Kg/day); an 
increase in relative testicular weight and liver weight (LOEL 12 mg/Kg/
day, NOEL 5.0 mg/Kg/day); possible GI complications related mortality 
(LOEL 45 mg/Kg/day, NOEL 15 mg/Kg/day); and miscellaneous effects on 
clinical chemistry, ketonuria, body weight depression, and clinical 
signs of distress (LOEL 45 mg/Kg/day, NOEL 15 mg/Kg/day).
    3. Chronic toxicity. Chronic toxicity studies (2-year rat and 1-
year dog) have not been conducted with RYH-86 due to the fact that its 
intended use pattern: (a) does not involve a potential for chronic 
occupational exposure; (b) leads to only negligible dietary exposure 
[see below]; and, (c) the only notable adverse effect observed in 
subchronic gavage studies with the rat was GI irritation / ulceration 
[see above]. Accordingly, Yoshitomi Fine Chemicals, Ltd. considers that 
significant chronic exposure is not an issue for RYH-86 as it is to be 
used and that the subchronic studies do not suggest that any unusual 
toxicity (other than GI irritation which is likely to be dose-limiting) 
will likely be seen in chronic toxicity studies. Indeed, the 
registration of RYH-86 Slimicide (EPA Reg. No. 63898-1) was supported 
by the Antimicrobials Data Call-in set of requirements and these 
provide specifically that chronic toxicity and oncogenicity studies for 
antimicrobial agents are required only if the results of subchronic 
toxicity or of gene toxicity studies indicate a potential concern or if 
there will, in fact, be significant chronic exposure.
    4. Oncogenicity. Oncogenicity studies (2-year rat and 18-months 
mouse) have not been conducted with RYH-86 due to the fact that its 
intended use pattern: (a) does not involve a potential for chronic or 
long term, frequent occupational exposure; (b) leads only to negligible 
dietary exposure [see below]; (c) the only notable adverse effect 
observed in subchronic gavage with the rat was GI irritation / 
ulceration with no evidence for metaplasia, dysplasia, altered foci, or 
peroxisome proliferation observed<SUP>1</SUP>; and, (d) RYH-86 is not 
mutagenic or genotoxic (see No. 6, below). Accordingly, Yoshitomi Fine 
Chemicals, Ltd. considers that significant chronic exposure is not an 
issue for RYH-86 as it is to be used and that the subchronic studies do 
not suggest that any unusual toxicity (other than GI irritation which 
is likely to be dose-limiting) or oncogenicity is likely to be seen in 
chronic toxicity / oncogenicity studies. Indeed, the registration of 
RYH-86 Slimicide (EPA Reg. No. 63898-1) was supported by the 
Antimicrobials Data Call-in set of requirements and these provide 
specifically that chronic toxicity and oncogenicity studies for 
antimicrobial agents are required only if the results of subchronic 
toxicity or of gene toxicity studies indicate a potential concern or if 
there will, in fact, be significant chronic exposure.
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    1 Suggesting that the more typical forms of pre-neoplastic 
lesions or lesions which have been associated with indirect 
carcinogenesis, and which can often be observed already within 90-
day studies, are not present.
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    5. Developmental toxicity. i. Rats - A standard Guideline 83-3 
design teratology and developmental effects study (MRID 42680801) was 
conducted in which maternal toxicity (as evidenced by decreases in body 
weight, body weight gain, food consumption, and thickening of the 
stomach mucosa) was observed at 45 mg/Kg/ day. At this dose (the 
highest dose tested) no developmental or teratological effects were 
observed. In this study, doses of 15 mg/Kg and lower were not toxic to 
the dams and there were no developmental or teratological effects at 
these lower doses. The dose selection for this study was based on the 
observed GI effects in the rat 90-day gavage study.
    ii. Rabbits or mice - Based on: (a) the lack of any suggestion of 
teratological or developmental effects at doses which produced frank 
maternal toxicity in the rat; (b) that the toxicity of RYH-86 in the 
rat study appeared to be largely a function of its GI effects; and, (c) 
the low exposure potential associated with RYH-86 in its intended uses, 
Yoshitomi Fine Chemicals, Ltd. considers that conduct of a second 
species developmental effect study is not needed to characterize the 
toxicology of RYH-86. Indeed, the registration of RYH-86 Slimicide (EPA 
Reg. No. 63898-1) was supported by the Antimicrobials Data Call-in set 
of requirements and these provide specifically that second species 
developmental toxicity studies for antimicrobial agents are required 
only if the results of studies in the first species indicate a 
potential concern or if there will, in fact, be significant exposure to 
females of child bearing age. The conclusion that a second species 
developmental toxicity study for RYH-86 is not needed has been reached 
to date by the Swedish, Finnish, and Canadian regulatory authorities in 
addition to EPA.
    6. Genotoxicity. In the standard Ames test (5-strains), RYH-86 is 
non-mutagenic with or without metabolic activation (MRID 42897501). In 
the mouse, in vivo, bone marrow

[[Page 49985]]

micronucleus test RYH-86 did not induce chromosome aberrations (MRID 
41531122). In the rat hepatocyte UDS (unscheduled DNA synthesis) test, 
RYH-86 did not induce unscheduled DNA synthesis (MRID 41531123). On the 
basis of this genotoxicity battery, Yoshitomi Fine Chemicals, Ltd. 
concludes that RYH-86 is not mutagenic or genotoxic.
    7. Metabolism. Specific mammalian metabolism studies with RYH-86 
have not been conducted for the following reasons: (a) at the alkaline 
pH of the small intestine, RYH-86 will hydrolyze rapidly with release 
of chloride and active chlorine; and, (b) the toxicology profile for 
RYH-86 indicates that the principle effect of RYH-86 is GI irritancy 
and that metabolism does not appear to play a significant role in the 
toxicology of RYH-86. Therefore, Yoshitomi Fine Chemicals, Ltd. 
considers that mammalian metabolism studies in the rat with RYH-86 will 
not provide additional useful information on the safety of RYH-86 and 
such studies were not required by EPA to support the registration of 
RYH-86 Slimicide (EPA Reg. No. 63898-1).
    8. Reference Dose (RfD). EPA has not previously set a RfD for RYH-
86 since at the time of registration review for RYH-86 Slimicide (EPA 
Reg. No. 63898-1) the regulation of RYH-86 residues in food contact 
paper and paperboard was under the jurisdiction of the Food and Drug 
Administration (FDA). Enactment of the Food Quality Protection Act 
transferred jurisdiction over these residues to EPA. Based on the 
subchronic NOEL of 3.8 mg/Kg/day (for gastro-intestinal (GI) irritation 
effects) and an uncertainty factor (UF) of 100, Yoshitomi Fine 
Chemicals, Ltd. proposes an RfD set at 0.038 mg/Kg/day for RYH-86. Such 
an RfD leads to the following allowable daily intakes (ADI) for adult 
males and females and for children: Adult male, 70 Kg, ADI = 2.7 mg/
day; Adult female, 60 Kg, ADI = 2.3 mg/day; Child, 20 Kg, ADI = 0.76 
mg/day. Yoshitomi Fine Chemicals, Ltd. has considered the possible 
special sensitivity to RYH-86 of infants and children and, also, of 
sensitive individuals. The proposed RfD is based on a physico-chemical 
effect of RYH-86: gastro-intestinal irritation. This, Yoshitomi Fine 
Chemicals, Ltd. suggests is not an effect for which any wide 
differences between infants / children and adults would be expected on 
a reasonable scientific basis. The irritant effects of RYH-86 on the GI 
tract are expected to be a function of the concentration of RYH-86 in 
the GI tract and this will be a function of amount of RYH-86 per unit 
of body weight. Thus, an RfD set at 0.038 mg/Kg/day will lead to 
similar GI tract concentrations of RYH-86 in adults, children, and 
infants. Also, since the effect of irritation is a physico-chemical 
effect, the existence of metabolic differences among persons is not 
reasonably expected to be a factor producing individuals with special 
sensitivity to RYH-86. Also, since: (a) physico-chemical effects like 
irritancy usually do not at all occur well below a threshold 
concentration of irritant; and, (b) the RfD is based on gavage studies 
in which RYH-86 is directly delivered to the gastric compartment 
whereas daily dietary consumption of the RfD amount leads to a lower 
peak GI tract level than would occur after gavage administration of the 
RfD amount, it can be expected that even for persons with pre-existing 
conditions such as ulcers, colitis, and similar pathologies that 
dietary exposures to RYH-86 at levels up to the proposed RfD will not 
exacerbate such conditions. Therefore, Yoshitomi Fine Chemicals, Ltd. 
believs that the proposed RfD is suitable for adults, children, 
infants, and persons with pre-existing GI tract disturbances.

C. Aggregate Exposure

    1. Dietary exposure ---- i. Food. GC-MS-SIM analysis of 
approximately 30 paper and paperboard samples manufactured in a 
papermill which used RYH-86 amended slurry water revealed no detectable 
RYH-86 with a detection limit of 100 <greek-m>g/Kg of paper (i.e., 100 
ppb). Extraction of such samples with food simulating solvents (FSL's), 
using standard FDA methods for determining food additive extractives 
from food-contact materials which allowed for the equilibration of RYH-
86 between the paper and paperboard samples and the FSL's for 10-days, 
revealed no RYH-86 migration into FSL's at detection limits of 10 
<greek-m>g/Kg for aqueous FSL's and 100 <greek-m>g/Kg for fatty FSL's 
(using the same GC-MS-SIM method for analysis). Using a standard 
equation provided by U.S. FDA for estimating dietary exposure to 
indirect food additives migrating from food packaging<SUP>2</SUP>, the 
hypothetical worst case potential for dietary exposure to RYH-86 as a 
result of migration into foods of RYH-86 residuals in food contact 
paper and paperboard is:
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    2 U.S. FDA (1985), ``Recommendations for Chemistry Data for 
Indirect Food Additive Petitions'', Center for Food Safety and 
Applied Nutrition, June 1995.
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    <M> = f<INF>aqueous and acidic</INF> 
(M<INF>10 percent ethanol</INF>) + f <INF>alcohol</INF> 
(M<INF>50 percent ethanol</INF>) + f<INF>fatty</INF> 
(M<INF>fatty</INF>)


    In which, for un-coated food contact paper and paperboard, the food 
type distribution factors (f<INF>food</INF> type) are:
    f<INF>aqueous and acidic</INF>    0.57 + 0.01 = 0.58
    f<INF>alcohol</INF>            0.01
    f<INF>fatty</INF>              0.41


    and <M> is the concentration of residues in food when the solvent 
to sample extraction ratio is 10 ml/sq. inch of sample surface (which 
was the case for Yoshitomi Fine Chemicals, Ltd.'s residue migration 
potential studies).
    For the worst case, since no RYH-86 was detected in any of the 
FSLs, Yoshitomi Fine Chemicals, Ltd. has taken the migration values (M) 
which would result if RYH-86 were present in the FSLs at the limit of 
detection for the relevant food simulating solvent type:
    M<INF>10 percent ethanol</INF>      10 <greek-m>g/Kg
    M<INF>50 percent ethanol</INF>      10 <greek-m>g/Kg
    M<INF>fatty</INF>            100 <greek-m>g/Kg


    In which case the overall migrant load, <M> is:
    <M> = (0.58  x  10 <greek-m>g/Kg) + (0.01  x  10 <greek-m>g/Kg) 
+ (0.41  x  100 <greek-m>g/Kg) = 47 <greek-m>g/Kg


    The above value of <M> can then be used for derivation of the 
estimated daily intake (EDI) for adults from the following FDA 
formula:<SUP>3</SUP>
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    3 Which considers that ``food'' consists of solid foods as well 
as beverages consumed.
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    EDI = 3.0 Kg food/day  x  <M>  x  CF


    where CF is the consumption factor for foods contacted by a given 
type of material. In the case of paper and paperboard, CF = 0.1 for 
uncoated paper (see footnote 2). Therefore, as a worst case, the 
potential adult EDI for RYH-86 which derives from possible residuals in 
food contact paper and paperboard is:
    EDI = 3.0 Kg food/day  x  47 <greek-m>g/Kg food  x  0.1 = 14.1 
<greek-m>g/day


    For children, the daily diet is different in quantity. At 6 months 
age, the daily caloric requirement is 110 cal/Kg body weight and the 
mean body weight for 6 months infants is 8 Kg. This equates to an 880 
Kg/day diet which at an average of 800 cal/Kg<SUP>4</SUP> is a 1.1 Kg 
total diet. In the age interval 4 years to 6 years of age (median body 
weight 20 Kg), the daily calorie requirement is 1,600 cal/day which 
equates to a 2 Kg total daily diet. The EDI's for infants and children 
are based on these total diet amounts:
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    4 The adult calorie requirement is 2,400 cal/day for males and 
females averaged and this in a 3 Kg daily diet provides for calorie 
density of 800 cal/Kg. For comparison, human breast milk has a 
calorie density of 700 cal/Kg.

    EDI<INF>INFANT</INF> = 1.1 Kg food/day  x  47 <greek-m>g/Kg  x  
---------------------------------------------------------------------------
0.1 = 5.2 <greek-m>g/day

    EDI<INF>CHILD</INF> = 2.0 Kg food/day  x  47 <greek-m>g/Kg  x  
0.1 = 9.4 <greek-m>g/day


    Thus, for a 6 month old infant, for a 20 Kg child (age 4-6), for a 
60 Kg

[[Page 49986]]

woman, and for a 70 Kg man, the daily intakes associated with the above 
EDI, expressed as <greek-m>g/Kg/day and as percent RfD utilization are:

                                                                        
------------------------------------------------------------------------
                                                          Percent RfD   
                                   Dietary Exposure        Utilized     
------------------------------------------------------------------------
Infant                            0.65 <greek-m>g/Kg/ 1.71              
                                   day                                  
Child                             0.47 <greek-m>g/Kg/ 1.24              
                                   day                                  
Woman                             0.24 <greek-m>g/Kg/ 0.632             
                                   day                                  
Man                               0.20 <greek-m>g/Kg/ 0.526             
                                   day                                  
------------------------------------------------------------------------


    Yoshitomi Fine Chemicals, Ltd. notes that at 40 CFR 180.1(l) EPA 
has defined that a ``negligible residue ... Ordinarily ... will add to 
the diet an amount which will be less than 1/2,000th of the amount that 
has been demonstrated to have no effect from feeding studies on the 
most sensitive animal species tested.'' This, for a 100-fold 
uncertainty factor based RfD, means an RfD utilization of 5% or less. 
Yoshitomi considers, therefore, that under the hypothetical worst case 
dietary exposure assessment RYH-86 residues are clearly negligible 
residues.
    i. Drinking water. The use of RYH-86 as a slimicide for pulp and 
paper mills does not provide for entry of RYH-86 into drinking water 
sources. Spent process water from such sites is treated as waste water, 
typically on-site, prior to release into surface waters. In a Finnish 
paper mill, with a use level of 1.5 ppm in the water (as an initial 
load to the slurry water) no RYH-86 was detected in air or water at 
sites by the paper making machine (detection limits were 4.5 ng/L in 
water and 3 x 10<SUP>-6</SUP> mg/dm<SUP>3</SUP>). Water samples which 
were examined included samples from the waste water holding pond and 
discharge from the on-site waste water treatment plant.
    2. Non-dietary exposure. RYH-86 is an industrial-use slimicide 
whose only other registered use (i.e., aside from slimicide use in pulp 
and paper mills) is as a slime control agent in re-circulating cooling 
water. All of the uses of RYH-86 involve only occupational exposures. 
There are no registrations and no intended uses in residential 
scenarios. There are, therefore, no Food Quality Protection Act covered 
non-dietary exposures to RYH-86.

D. Cumulative Effects

    There is no reliable information to indicate that RYH-86 has a 
common mechanism of toxicity with any other chemical compound.

E. Safety Determination

    1. U.S. population. Since the use of RYH-86 as a slimicide in pulp 
and paper mills is, under hypothetical worst case conditions, 
anticipated to lead to only negligible adult dietary exposures (i.e., 
not greater than 0.63% of the RfD for adults with ``negligible'' 
defined at 40 CFR 180.1(l) as ``ordinarily'' not greater than 5% of the 
RfD) Yoshitomi Fine Chemicals, Ltd. concludes that there is a 
reasonable certainty that no harm to the general adult population will 
result from dietary exposure to RYH-86 residues which could occur in 
food contact paper and paperboard produced in pulp and paper mills 
utilizing RYH-86 for slime control in accordance with its FIFRA 
labeling.
    2. Infants and children. Since the use of RYH-86 as a slimicide in 
pulp and paper mills is, under hypothetical worst case conditions, 
anticipated to lead to only negligible dietary exposures (i.e., not 
greater than 1.71% of the RfD for infants and not greater than 1.24% of 
the RfD for children with ``negligible'' defined at 40 CFR 180.1(l) as 
``ordinarily'' not greater than 5% of the RfD) Yoshitomi Fine 
Chemicals, Ltd. concludes that there is a reasonable certainty that no 
harm to infants and children will result from dietary exposure to RYH-
86 residues which could occur in food contact paper and paperboard 
produced in pulp and paper mills utilizing RYH-86 for slime control in 
accordance with its FIFRA labeling.
    3. Sensitive individuals. The RfD for RYH-86 is based on gastro-
intestinal irritation as the effect which occurs at lowest dose in 
animal gavage studies. Since the effect of irritation is a physico-
chemical effect, the existence of metabolic differences among persons 
is not reasonably expected to be a factor producing individuals with 
special sensitivity to RYH-86. Also, since: (a) physico-chemical 
effects like irritancy usually do not at all occur well below a 
threshold concentration of irritant; and, (b) the RfD is based on 
gavage studies in which RYH-86 is directly delivered to the gastric 
compartment whereas daily dietary consumption of the RfD amount leads 
to a lower peak GI tract level than would occur after gavage 
administration of the RfD amount, it can be expected that even for 
persons with pre-existing conditions such as ulcers, colitis, and 
similar pathologies that dietary exposures to RYH-86 at levels up to 
the proposed RfD will not exacerbate such conditions. Therefore, 
Yoshitomi Fine Chemicals, Ltd. concludes that there is a reasonable 
certainty that no harm to persons with pre-existing GI-tract problems 
will result from dietary exposure to RYH-86 residues which could occur 
in food contact paper and paperboard produced in pulp and paper mills 
utilizing RYH-86 for slime control in accordance with its FIFRA 
labeling.

F. International Tolerances

    There are no Codex maximum residue levels (MRLs) established for 
residues of RYH-86 resulting from the use of RYH-86.

[FR Doc. 97-25338 Filed 9-23-97; 8:45 am]
BILLING CODE 6560-50-F


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