[Federal Register Volume 63, Number 53 (Thursday, March 19, 1998)]
[Notices]
[Pages 13404-13409]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-7140]


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ENVIRONMENTAL PROTECTION AGENCY

[PF-796; FRL-5776-6]


Notice of Filing of Pesticide Petitions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: This notice announces the initial filing of pesticide 
petitions proposing the establishment of regulations for residues of 
certain pesticide chemicals in or on various agricultural commodities.

DATES: Comments, identified by the docket control number PF-796, must 
be received on or before April 20, 1998.

ADDRESSES: By mail submit written comments to: Public Information and 
Records Integrity Branch, Information Resources and Services Divison 
(7502C), Office of Pesticides Programs, Environmental Protection 
Agency, 401 M St., SW., Washington, DC 20460. In person bring comments 
to: Rm. 119, CM #2, 1921 Jefferson Davis Highway, Arlington, VA.
    Comments and data may also be submitted electronically to: opp-
[email protected]. 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

[[Page 13405]]

inspection in Rm. 119 at the address given above, from 8:30 a.m. to 4 
p.m., Monday through Friday, excluding legal holidays.

FOR FURTHER INFORMATION CONTACT: The product manager listed in the 
table below:

------------------------------------------------------------------------
                                   Office location/                     
 Product Manager/Petition No.     telephone number/e-        Address    
                                     mail address                       
------------------------------------------------------------------------
Bipin Gandhi (PM 5); (PP        Rm. 4W53, Crystal       2800 Crystal    
 7E4918).                        Station, 703-308-       Dr., Arlington,
                                 8380, e-mail:           VA             
                                 gandhi.bipin@epamail.
epa.gov.                               
Sidney Jackson (PM 5); (PP      Rm. 233, CM #2, 703-    1921 Jefferson  
 5E4463).                        305-7610, e-mail:       Davis Hwy,     
                                 jackson.sidney@epamai   Arlington, VA  
                                 l.epa.gov.                             
------------------------------------------------------------------------


SUPPLEMENTARY INFORMATION: EPA has received pesticide petitions as 
follows proposing the establishment and/or amendment of regulations for 
residues of certain pesticide chemicals in or on various raw 
agricultural commodities under section 408 of the Federal Food, Drug, 
and Comestic Act (FFDCA), 21 U.S.C. 346a. EPA has determined that these 
petitions contain 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 grantinig of the petition. Additional data may be needed 
before EPA rules on the petition.
    The official record for this notice, as well as the public version, 
has been established for this notice of filing under docket control 
number PF-796 (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'' at the 
beginning of this document.
    Electronic comments can be sent directly to EPA at:
    [email protected]


    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 5.1/6.1 file format or 
ASCII file format. All comments and data in electronic form must be 
identified by the docket control number PF-796 and appropriate petition 
number. Electronic comments on this notice may be filed online at many 
Federal Depository Libraries.
    Authority: 21 U.S.C. 346a.

List of Subjects

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

    Dated: March 5, 1998.

James Jones,
Director, Registration Division, Office of Pesticide Programs.

Summaries of Petitions

    Below summaries of the pesticide petitions are printed. The 
summaries of the petitions were prepared by the petitioners. 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.

1. Hercon Environmental Corporation

PP 7E4918

    EPA has received a pesticide petition (PP 7E4918) from Hercon 
Environmental Corporation, Aberdeen Road, P.O. box 467, Emigsville, PA 
17318-0467, proposing pursuant to section 408(d) of the Federal Food, 
Drug and Cosmetic Act, 21 U.S.C. 346a(d), to amend 40 CFR part 180 to 
establish an exemption from the requirement of a tolerance for Trioctyl 
Trimellitate (TOTM) as an inert ingredient under 40 CFR 180.1001(c).

A. Product Identity/Chemistry

    Tris(2-ethylhexyl)1,2,4-benzenetricarboxylate, the chemical name 
for TOTM, CAS # [3319-31-1], has a molecular formula of C33 
H45 O6, and a molecular weight of 546.8.
    TOTM is a primary plasticizer used in applications requiring good 
elongation retention such as high-temperature PVC wire coatings. Its 
excellent resistance to soapy water extraction also makes it attractive 
for use in vinyl film and vinyl-coated fabrics. Its stereochemical 
properties make it especially attractive in pheromone formulations as a 
control-release agent, and its extremely low vapor pressure (0.7  x  
10-7 mm Hg), assures its retention in the formulation to 
perform its intended purpose.

B. Residue Chemistry

    No residue chemistry data are available. However, arguments 
provided above relative to modes of exposure, support the lack of 
potential for any residues of TOTM to be present in raw agricultural 
product of the foods from them.
    Since this petition requests an exemption from the requirement of a 
tolerance, Hercon believes that an analytical method for the detection 
and measurement of TOTM residues is not necessary. The low rate of 
application and the fact that it is encapsulated in the product leads 
to the conclusion that TOTM will not migrate into a food from the 
treatment of crops to any degree that would be detectable.

C. Toxicological Profile

    Hercon has submitted to the EPA acute toxicological information and 
studies of chronic toxicology which exhibit the low toxicity of TOTM. 
In addition, it was determined from a manufacturer that no reports have 
been submitted on TOTM under TSCA 8(e) Substantial Risk Notification 
requirements.
    1. Acute toxicity. Acute toxicology studies conducted with the 
``neat'' material show:
    Acute Toxicity:   At most only slightly toxic. Slight skin 
irritant. LD50 >3200 mg/kg.
    Skin Absorption and Irritation:   No evidence of skin 
absorption. LD50 >20 mg/kg
    Skin Sensitization:   Sensitized 0/5 guinea pigs in drop-on 
test.
    Inhalation:   At lowest exposure of 0.23 mg/l, no mortality was 
experienced.
    Eye Irritation:   In unwashed eye, there was an initial moderate 
effect after 1 hour, but the effect disappeared after 48 hours. No 
effects reported in the washed eye.


    2. Genotoxicty. -- a. TOTM evaluation in the CHO/HGPRT forward 
mutation assay. TOTM was considered to be inactive under the conditions 
of testing in this assay. The test material did not induce dose-related 
increases in the mutant frequency at the HGPRT locus in CHO cell 
cultures. TOTM was not toxic to CHO cells at concentrations up to 5,000 
nl/ml either with or without S9 metabolic activation. Mutation assays 
were performed in duplicate both with

[[Page 13406]]

a nd without S9 metabolic activation using 6 concentrations of TOTM 
ranging from 10.0 nl/ml to 200 nl/ml.
    b. Evaluation of TOTM in the rat primary hepatocyte unscheduled DNA 
synthesis assay. The test material did not induce significant changes 
in the nuclear labeling of primary rat hepatocytes for an applied 
concentration range of 5000 nl/ml to 250 nl/ml. Little or no toxicity 
was observed (88.4% to 102.2% survival) but higher concentrations could 
not be assayed because of the insoluble nature of TOTM in medium. None 
of the criteria used to indicate UDS were approached by the treatments, 
and no dose-related response was observed. Therefore, the test material 
was evaluated as inactive in the Primary Rat Hepatocyte UDS Assay.
    3. Subchronic toxicity. Twenty-eight Day Toxicity Study with TOTM 
in the Rat: The results of this study demonstrates that TOTM caused 
slight peroxisome proliferation but was less potent than DEHP [di(2-
ethylhexyl) phthalate], with 2.0% TOTM producing less effects than 
0.67% DEHP. There was no effect of feeding TOTM on the body weight or 
food intakes of the male rats. The females fed 2.0% TOTM showed an 
initial rejection of the diet which did not have any marked effect on 
their weight gain.
    4. Chronic toxicity. Chronic Toxicity of TOTM to Daphnia magna 
Under Flow-Through Test Conditions: The daphnid lengths in all TOTM 
mean measured concentrations after 21 days of testing were not 
significantly different (a = 0.05) from the control. Statistical 
analysis of survival for Daphnia magna after a 21 days exposure to TOTM 
indicated that survival rates in all the mean measured test 
concentrations were not significantly different from the control. The 
mean young/adult/reproduction day after 21 days was not significantly 
affected in a deleterious manner in all mean measured test 
concentrations of TOTM. Based on the statistical analysis of adult mean 
length, survival and young/adult/reproduction day from the 21 day 
Daphnia magna dynamic life cycle study, the MATC (Maximum Acceptable 
Toxicant Concentration) limits were estimated to be greater than the 
TOTM mean measured concentration of 82 g/l.
    5. Metabolite toxicology. Study No. 4: Absorption and Metabolism of 
[Hexyl-2-14C] TOTM: TOTM is called TEHT in this study. These studies 
show that TEHT was hydrolyzed to a limited extent in the 
gastrointestinal tract and was largely excreted unchanged in the feces. 
Sixteen percent was excreted in the urine as metabolites and 1.9% was 
expired as CO2.

D. Aggregate Exposure

    Hercon's pheromone formulations containing TOTM will not result in 
an application rate of product in which more than 25 grams/acre of TOTM 
on food related crops will result. Depending on an extended or delayed 
infestation of target pests, no more than 3 applications per crop 
should be necessary.
    It must be remembered that this amount of TOTM is contained in the 
formulated device, a 0.05 square inch laminated PVC flake, and 
therefore the TOTM itself does not come into direct contact with the 
plants or crops treated. At the maximum application rate, there are 
approximately 0.26 flakes per square foot. This equates to 
approximately 0.5 mg TOTM / sq.ft. At the lowest recommended 
application rate, this amount is halved.
    To present a worst case scenario for dietary exposure to humans, 
Hercon has selected applications to a sugar cane crop. This worst case 
scenario hypothetically presumes that all available TOTM in the product 
is finally present in the processed sugar.
    At an application rate corresponding to 0.5 mg TOTM/sq.ft, and a 
harvest resulting in 3.3 tons of sugar per acre, the available 
concentration of TOTM in the sugar would calculate to be 8.4 mg TOTM / 
Kg of sugar.
    The assumption of an intake of 20 gms of sugar per day, would 
equate to a daily intake of 0.168 mg of TOTM. This hypothetical intake 
is much lower than the NOEL from a 28 day Chronic oral study in the 
male rat of 185 mg/kg/day noted in the MSDS.
    Actually, it is expected that since the TOTM is contained in the 
formulated devise, that no detectable TOTM would be found in the sugar.
    Exposure to drinking water will be minimal. Hercon's products 
containing TOTM are not sprayed on lawns or gardens, around swimming 
pools, etc., and due to the low rates of application, even drift from 
an agricultural application to lakes or waterways, will not affect 
drinking water.
    Data, calculations, low exposure potential and low toxicity 
discussed and presented in this petition request, precludes a concern 
for significant dietary or non-dietary exposure to infants and 
children.
    Non-dietary exposure to TOTM will be mitigated through the use of 
personal protective equipment which is described on the label of 
products for personnel which may be around or in a treated field.

E. Cumulative Exposure

    No cumulative mode of exposure is expected. Again, the application 
rate is extremely low, and encapsulation of the TOTM in the product 
prevents direct exposure.
    Normal use patterns will not lead to accumulation of TOTM in the 
environment.

F. Safety Determinations

    Hercon believes that the use of pheromone products containing TOTM, 
which is of low toxicity and which is used in such low concentrations, 
is compatible with EPA's objectives to register reduced risk 
pesticides.
    In an absorption and metabolism study on rats, which is included in 
this package, 75% of the dose was excreted in the feces, 16% in the 
urine, and 1.9% was expired as CO2. Less than 0.6% remained in the 
tissues.
    At an acute oral LD50 toxicity level of >3200 mg/kg in 
the rat and mouse, TOTM is a low level toxin with at most a class III 
toxicity rating. A 28 day Chronic Oral toxicity study resulted in a 
NOEL of 184 mg/kg/day.
    Mutagenicity and Genotoxicity data showed negative results in 
Salmonella typhimurium assay, DHO/HGPRT assay and the Unscheduled DNA 
synthesis assay.
    Because of the low toxcicity of TOTM and the low rate of 
application, and encapsulation in the product, and more importantly 
because no residue is expected in the final food product, a 
determination can be made that there is little or no exposure to the 
general population or to children and infants.

G. List of International Tolerances

    The petitioner understands that therte are no current or known 
established residue levels for TOTM.

H. Environmental Fate Summary

    This summary is taken directly from the Material Safety Data Sheet 
from Eastman Chemical Co.
    ``Data for this material have been used to estimate its 
environmental impact. It has the following properties: a low 
biochemical oxygen demand and little potential to cause oxygen 
depletion in aqueous systems, a low potential to affect aquatic 
organisms, a low potential to biodegrade (high persistence) with 
acclimated microorganisms from activated sludge, a low potential to 
bio-concentrate. After dilution with a large amount of water, 
followed by secondary waste treatment, this material is not expected 
to cause adverse environmental effects.''



[[Page 13407]]



2. IR-4 Project

PP 5E4463

    EPA has received a pesticide petition (PP 5E4463) from the 
Interregional Research Project Number 4 (IR-4), 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 insecticide cypermethrin ((+) alpha-cyano(3-
phenoxyphenyl)methyl (+) cis, trans 3-(2,2-dichloroethenyl)-2,2-
dimethylcyclopropanecarboxylate) in or on the raw agricultural 
commodity green onions at 6.0 parts per million (ppm). EPA has 
determined that the petition contains data or information regarding the 
elements set forth in section 408(d)(2) of the FFDCA; however, EPA has 
not fully evaluated the sufficiency of the submitted data at this time 
or whether the data support granting of the petition. Additional data 
may be needed before EPA rules on the petition. This notice contains a 
summary of the petition submitted by FMC Corporation, the registrant.

A. Residue Chemistry

    1. Plant metabolism. The metabolism of cypermethrin in plants is 
adequately understood. Studies have been conducted to delineate the 
metabolism of radiolabelled cypermethrin in various crops all showing 
similar results. The residue of concern is the parent compound only.
    2. Analytical method. There is a practical analytical method for 
detecting and measuring levels of cypermethrin in or on food with a 
limit of detection that allows monitoring of food with residues at or 
above the levels set in these tolerances. The analytical method is Gas 
Chromatography with Electron Capture Detection (GC/ECD).
    3. Magnitude of residues. Field residue trials meeting EPA study 
requirements have been conducted at the maximum label rate for the crop 
green onions. Results from these trials demonstrate that the proposed 
cypermethrin tolerance on green onions at 6.0 ppm will not be exceeded 
when the product is applied following the proposed use directions. 
These data have previously been reviewed and classified by the Agency 
as supportive of this tolerance.

B. Toxicological Profile

    1. Acute toxicity. The required battery of acute toxicity studies 
has been submitted and found adequate. The findings were as follows: 
oral toxicity, lethal dose (LD)50 of 263 milligram (mg) per 
kilogram (kg); dermal toxicity, LD50 2,460 mg/kg; inhalation 
toxicity lethal concentration LC50 2.5 mg/liter (L); primary 
eye irritation is Toxicity Category III; primary dermal irritation is 
Toxicity Category IV. Cypermethrin is considered to be a dermal 
sensitizer.
    2. Genotoxicity. All reported results from the following 
genotoxicity tests were all negative: gene mutation (Ames); chromosome 
aberration in Chinese hamster bone marrow cells; host mediated assay in 
mice; dominant lethal assay in mice.
    3. Reproductive and developmental toxicity. No evidence of 
additional sensitivity to young rats or rabbits was reported following 
pre- or postnatal exposure to cypermethrin.
    a. A 3-generation reproductive toxicity study in rats demonstrated 
a no observed effect level (NOEL) of 2.5 mg/kg/day and a lowest 
observed effect level (LOEL) of 7.5 mg/kg/day for parental/systemic 
toxicity based on decreased body weight gain in both sexes. There were 
no adverse effects in reproductive performance. The NOEL for 
reproductive toxicity was considered to be 37.5 mg/kg/day, the highest 
dose level tested.
    b. A developmental study in rats demonstrated a maternal NOEL of 
17.5 mg/kg/day and a LOEL of 35 mg/kg/day based on decreased body 
weight gain. There were no signs of developmental toxicity at 70 mg/kg/
day, the highest dose level tested.
    c. A developmental study in rabbits demonstrated a maternal NOEL of 
100 mg/kg/day and a LOEL of 450 mg/kg/day based on decreased body 
weight gain. There were no signs of developmental toxicity at 700 mg/
kg/day, the highest dose level tested.
    4. Subchronic toxicity. The systemic NOEL of 5.0 mg/kg/day from the 
chronic toxicity study in dogs is also used for short- and 
intermediate-term margin of exposure (MOE) calculations (as well as 
acute toxicity, discussed in (1) above). This NOEL was based on 
neurotoxic clinical signs observed in the first week of treatment of 
the study.
    5. Chronic toxicity. The Reference Dose (RfD) has been established 
at 0.010 mg/kg/day. This RfD is based on a chronic toxicity study in 
dogs with a NOEL of 1.0 mg/kg/day, based on gastrointestinal 
disturbances observed at the LOEL of 5.0 mg/kg/day during the first 
week of the study; an uncertainty factor of 100 is used.
    Cypermethrin is classified as a Group C chemical (possible human 
carcinogen with limited evidence of carcinogenicity in animals) based 
upon limited evidence for carcinogenicity in female mice; assignment of 
a Q* has not been recommended.
    6. Animal metabolism. The metabolism of cypermethrin in animals is 
adequately understood. Cypermethrin has been shown to be rapidly 
absorbed, distributed, and excreted in rats when administered orally. 
Cypermethrin is metabolized by hydrolysis and oxidation.
    7. Metabolite toxicology. The Agency has previously determined that 
the metabolites of cypermethrin are not of toxicological concern and 
need not be included in the tolerance expression.
    8. Endocrine disruption. No evidence of potential estrogenic or 
other endocrine effects of cypermethrin were reported in the standard 
battery of required toxicology studies which have been completed and 
found acceptable. Based on these studies, there is no evidence to 
suggest that cypermethrin has an adverse effect on the endocrine 
system.

C. Aggregate Exposure

    1. Dietary exposure. a. Food. Tolerances have been established for 
the residues of cypermethrin, in or on a variety of raw agricultural 
commodities. Tolerances, in support of registrations, currently exist 
for residues of cypermethrin on cottonseed; pecans; lettuce, head; 
onions, bulb; cabbage; Brassica, head and stem; Brassica, leafy and 
livestock commodities of cattle, goats, hogs, horses, and sheep as well 
as this pending tolerance for green onions. For the purposes of 
assessing the potential dietary exposure for these existing and pending 
tolerances, FMC has utilized available information on anticipated 
residues, monitoring data and percent crop treated as follows:
    i. Acute exposure and risk. Acute dietary exposure risk assessments 
are performed for a food-use pesticide if a toxicological study has 
indicated the possibility of an effect of concern occurring as a result 
of a one day or single exposure. For the purposes of assessing acute 
dietary risk for cypermethrin, the maternal NOEL of 1.0 mg/kg/day from 
the chronic toxicity study in dogs was used. The LOEL of this study of 
5.0 mg/kg/day was based on gastrointestinal disturbances observed in 
the first week of the study. This acute dietary endpoint was used to 
determine acute dietary risks to all population subgroups. Available 
information on anticipated residues, monitoring data and percent crop 
treated was incorporated into a Tier 3 analysis, using Monte Carlo 
modeling for commodities that may be consumed in a single serving. 
These assessments show that the MOEs are significantly greater than the 
EPA standard of 100 for all subpopulations. The 95th percentile

[[Page 13408]]

of exposure for the overall U. S. population was estimated to be 
0.000488 mg/kg/day (MOE of 2,047); 99th percentile 0.002014 mg/kg/day 
(MOE of 496); and 99.9th percentile 0.004438 mg/kg/day (MOE of 225). 
The 95th percentile of exposure for all infants < one year old was 
estimated to be 0.00007 mg/kg/day (MOE of 14,240); 99th percentile 
0.000345 mg/kg/day (MOE of 2,902); and 99.9th percentile 0.000997 mg/
kg/day (MOE of 1,003). The 95th percentile of exposure for nursing 
infants < one year old was estimated to be 0.000033 mg/kg/day (MOE of 
30,026 ); 99th percentile 0.000241 mg/kg/day (MOE of 4,144); and 99.9th 
percentile 0.001400 mg/kg/day (MOE of 714). The 95th percentile of 
exposure for non-nursing infants < one year old was estimated to be 
0.000075 mg/kg/day (MOE of 13,331); 99th percentile 0.000375 mg/kg/day 
(MOE of 2,667); and 99.9th percentile 0.000748 mg/kg/day (MOE of 
1,337). The 95th percentile of exposure for children 1 to 6 years old 
(the most highly exposed population subgroup) was estimated to be 
0.000361 mg/kg/day (MOE of 2,767); 99th percentile 0.002088 mg/kg/day 
(MOE of 479); and 99.9th percentile 0.005465 mg/kg/day (MOE of 183). 
Therefore, FMC concludes that the acute dietary risk of cypermethrin, 
as estimated by the dietary risk assessment, does not appear to be of 
concern.
    ii. Chronic exposure and risk. The acceptable RfD is based on a 
NOEL of 1.0 mg/kg/day from the chronic dog study and an uncertainty 
factor of 100 is 0.010 mg/kg/day. The endpoint effect of concern was 
based on gastrointestinal disturbances observed in the first week of 
the study at the LOEL of 5.0 mg/kg/day. A chronic dietary exposure/risk 
assessment has been performed for cypermethrin using the above RfD. 
Available information on anticipated residues, monitoring data and 
percent crop treated was incorporated into the analysis to estimate the 
anticipated residue contribution (ARC). The ARC is generally considered 
a more realistic estimate than an estimate based on tolerance level 
residues. The ARC is estimated to be 0.000025 mg/kg body weight (bwt)/
day and utilize 0.3 percent of the RfD for the overall U. S. 
population. The ARCs for non-nursing infants (<1 year) and children 1-6 
years old (subgroups most highly exposed) are estimated to be 0.000014 
mg/kg bwt/day and 0.000042 mg/kg bwt/day and utilizes 0.1 percent and 
0.4 percent of the RfD, respectively. Generally speaking, the EPA has 
no cause for concern if the total dietary exposure from residues for 
uses for which there are published and proposed tolerances is less than 
100 percent of the RfD. Therefore, FMC concludes that the chronic 
dietary risk of cypermethrin, as estimated by the dietary risk 
assessment, does not appear to be of concern.
    b. Drinking water. Laboratory and field data have demonstrated that 
cypermethrin is immobile in soil and will not leach into groundwater. 
Other data show that cypermethrin is virtually insoluble in water and 
extremely lipophilic. As a result, FMC concludes that residues reaching 
surface waters from field runoff will quickly adsorb to sediment 
particles and be partitioned from the water column. Further, a 
screening evaluation of leaching potential of a typical pyrethroid was 
conducted using EPA's Pesticide Root Zone Model (PRZM3). Based on this 
screening assessment, the potential concentrations of a pyrethroid in 
groundwater at depths of 1 and 2 meters are essentially zero (<<0.001 
parts per billion). Surface water concentrations for pyrethroids were 
estimated using PRZM3 and Exposure Analysis Modeling System (EXAMS) 
using standard EPA cotton runoff and Mississippi pond scenarios. The 
maximum concentration predicted in the simulated pond was 0.052 parts 
per billion(ppb). Concentrations in actual drinking water would be much 
lower than the levels predicted in the hypothetical, small, stagnant 
farm pond model since drinking water derived from surface water would 
normally be treated before consumption. Based on these analyses, FMC 
believes that the contribution of water to the dietary risk estimate is 
negligible. Therefore, FMC concludes that together these data indicate 
that residues of cypermethrin are not expected to occur in drinking 
water.
    2. Non-dietary exposure. Analyses were conducted which included an 
evaluation of potential non-dietary (residential) applicator, post-
application and chronic dietary aggregate exposures associated with 
cypermethrin products used for residential flea infestation control and 
agricultural/commercial applications. The aggregate analysis 
conservatively assumes that a person is concurrently exposed to the 
same active ingredient via the use of consumer or professional flea 
infestation control products and to chronic level residues in the diet.
    In the case of potential non-dietary health risks, conservative 
point estimates of non-dietary exposures, expressed as total systemic 
absorbed dose for each product use category (indoor total release 
fogger and lawn care) and exposed population group (adults, children 1-
6 years, and infants < 1 year) are compared to the systemic absorbed 
dose NOEL for cypermethrin to provide estimates of the MOEs. Based on 
the toxicity endpoints selected by EPA for cypermethrin, inhalation and 
incidental oral ingestion absorbed doses were combined and compared to 
the relevant systemic NOEL for estimating MOEs.
    In the case of potential aggregate health risks, the above 
mentioned conservative point estimates of non-dietary exposure 
(expressed as systemic absorbed dose) are combined with estimates 
(arithmetic mean values) of chronic average dietary (oral) absorbed 
doses. These aggregate absorbed dose estimates are also provided for 
adults, children 1 - 6 years and infants < 1 year. The combined or 
aggregated absorbed dose estimates (summed across non-dietary and 
chronic dietary) are then compared with the systemic absorbed dose NOEL 
to provide estimates of aggregate MOEs.
    The total non-dietary MOEs (combined across all product use 
categories) for the inhalation plus incidental oral routes are 97,000 
for adults, 2,100 for children 1-6 years old, and 1,900 for infants (< 
1 year). The aggregate MOE (inhalation + incidental oral + chronic 
dietary, summed across all product use categories) was estimated to be 
65,000 for adults, 2,000 for children 1-6 years old and 1,900 for 
infants (<1 year). FMC concludes that the potential non-dietary and 
aggregate (non-dietary + chronic dietary) exposures for cypermethrin 
are associated with substantial margins of safety.

D. Cumulative Effects

    In consideration of potential cumulative effects of cypermethrin 
and other substances that may have a common mechanism of toxicity, to 
our knowledge there are currently no available data or other reliable 
information indicating that any toxic effects produced by cypermethrin 
would be cumulative with those of other chemical compounds; thus only 
the potential risks of cypermethrin have been considered in this 
assessment of its aggregate exposure. FMC intends to submit information 
for the EPA to consider concerning potential cumulative effects of 
cypermethrin consistent with the schedule established by EPA at in the 
Federal Register of August 4, 1997, (62 FR 42020), and other EPA 
publications pursuant to the Food Quality Protection Act.

[[Page 13409]]

E. Safety Determination

    1. U.S. population. Based on a complete and reliable toxicology 
database, the acceptable reference dose RfD is 0.010 mg/kg/day, based 
on a LOEL of 5.0 mg/kg/day from the chronic dog study and an 
uncertainty factor of 100. Available information on anticipated 
residues, monitoring data and percent crop treated was incorporated 
into an analysis to estimate the Anticipated Residue Contribution (ARC) 
for 26 population subgroups. The ARC is generally considered a more 
realistic estimate than an estimate based on tolerance level residues. 
The ARC are estimated to be 0.000025 mg/kg body weight (bwt)/day and 
utilize 0.3 percent of the RfD for the overall U. S. population. The 
ARC for non-nursing infants (<1 year) and children 1-6 years old 
(subgroups most highly exposed) are estimated to be 0.000014 mg/kg bwt/
day and 0.000042 mg/kg bwt/day and utilizes 0.1 percent and 0.4 percent 
of the RfD, respectively. Generally speaking, the EPA has no cause for 
concern if the total dietary exposure from residues for uses for which 
there are published and proposed tolerances is less than 100 percent of 
the RfD. Therefore, FMC concludes that the chronic dietary risk of 
cypermethrin, as estimated by the aggregate risk assessment, does not 
appear to pose significant risk.
    For the overall U.S. population, the calculated margins of exposure 
(MOE) at the 95th percentile was estimated to be 2,047; 496 at the 99th 
percentile; and 225 at the 99.9th percentile. For all infants < one 
year old, the calculated MOE at the 95th percentile was estimated to be 
14,240; 2,902 at the 99th percentile; and 1,003 at the 99.9th 
percentile. For nursing infants < one year old, the calculated margins 
of exposure (MOE) at the 95th percentile was estimated to be 30,026; 
4,144 at the 99th percentile; and 714 at the 99.9th percentile. For 
non-nursing infants < one year old, the calculated margins of exposure 
(MOE) at the 95th percentile was estimated to be 13,331; 2,667 at the 
99th percentile; and 1,337 at the 99.9th percentile. For the most 
highly exposed population subgroup, children 1 - 6 years old, the 
calculated MOE at the 95th percentile was estimated to be 2,767 ; 479 
at the 99th percentile; and 183 at the 99.9th percentile. Therefore, 
FMC concludes that there is reasonable certainty that no harm will 
result from acute exposure to cypermethrin.
    2. Infants and children. --a. General. In assessing the potential 
for additional sensitivity of infants and children to residues of 
cypermethrin, FMC considered data from developmental toxicity studies 
in the rat and rabbit, and a three-generation reproductive study in the 
rat. The data demonstrated no indication of increased sensitivity of 
rats or rabbits to in utero and/or postnatal exposure to cypermethrin. 
The developmental toxicity studies are designed to evaluate adverse 
effects on the developing organism resulting from pesticide exposure 
during prenatal development to one or both parents. Reproduction 
studies provide information relating to effects from exposure to the 
pesticide on the reproductive capability of mating animals and data on 
systemic toxicity. FFDCA section 408 provides that EPA may apply an 
additional margin of safety for infants and children in the case of 
threshold effects to account for pre- and post-natal toxicity and the 
completeness of the database.
    b. Developmental toxicity studies. In the prenatal developmental 
toxicity studies in rats and rabbits, there was no evidence of 
developmental toxicity at the highest doses tested (70 mg/kg/day in 
rats and 700 mg/kg/day in rabbits). Decreased body weight gain was 
observed at the maternal LOEL in each study; the maternal NOEL was 
established at 17.5 mg/kg/day in rats and 100 mg/kg/day in rabbits.
    c. Reproductive toxicity study. In the 3-generation reproduction 
study in rats, offspring toxicity (reduced mean litter weight gain) was 
observed only at the highest dietary level tested (37.5 mg/kg/day), 
while toxicity in the parental animals was observed at the lower 
treatment levels. The parental systemic NOEL was 2.5 mg/kg/day and the 
parental systemic LOEL was 7.5 mg/kg/day. There were no developmental 
(pup) or reproductive effects up to 37.5 mg/kg/day (highest dose 
tested).
    d. Pre- and post-natal sensitivity. --i. Pre-natal. There was no 
evidence of developmental toxicity in the studies at the highest doses 
tested in the rat (70 mg/kg/day) or in the rabbit (700 mg/kg/day). 
Therefore, there is no evidence of a special dietary risk (either acute 
or chronic) for infants and children which would require an additional 
safety factor.
    ii. Post-natal. Based on the absence of pup toxicity up to dose 
levels which produced toxicity in the parental animals, there is no 
evidence of special post-natal sensitivity to infants and children in 
the rat reproduction study.
    Based on the above, FMC concludes that reliable data support use of 
the standard 100-fold uncertainty factor, and that an additional 
uncertainty factor is not needed to protect the safety of infants and 
children. As stated above, aggregate exposure assessments utilized 
significantly less than 1 percent of the RfD for either the entire U. 
S. population or any of the 26 population subgroups including infants 
and children. Therefore, FMC concludes that there is reasonable 
certainty that no harm will result to infants and children from 
aggregate exposure to cypermethrin residues.

F. International Tolerances

    There are no codex, Canadian, or Mexican residue limits for 
residues of cypermethrin in or on green onions.

[FR Doc. 98-7140 Filed 3-18-98; 8:45 am]
BILLING CODE 6560-50-F