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paraquat Pesticide Petition Filing 11/99



[Federal Register: December 3, 1999 (Volume 64, Number 232)]
[Notices]               
[Page 67905-67912]
>From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr03de99-87]                         

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ENVIRONMENTAL PROTECTION AGENCY

[PF-900; FRL-6392-6]

 
Notice of Filing Pesticide Petitions To Establish a Tolerance for 
Certain Pesticide Chemicals in or on Food

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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

DATES: Comments, identified by docket control number PF-900, must be 
received on or before January 3, 2000.

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'' section. To 
ensure proper receipt by EPA, it is imperative that you identify docket 
control number PF-900 in the subject line on the first page of your 
response.

FOR FURTHER INFORMATION CONTACT:  By mail: Shaja Brothers, Registration 
Support Branch, Registration Division (7505C), Office of Pesticide 
Programs, Environmental Protection Agency, 401 M St., SW., Washington, 
DC 20460; telephone number: (703) 308-3194; and e-mail address: 
brothers.shaja@epa.gov.

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            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 in the ``FOR FURTHER INFORMATION 
CONTACT'' section.

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'' 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-900. 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

[[Page 67906]]

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-900 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, 401 M St., SW., 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: ``opp-docket@epa.gov,'' or you can submit a computer disk as 
described above. Do not submit any information electronically that you 
consider to be 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-900. 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 in the ``FOR FURTHER INFORMATION 
CONTACT'' section.

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 pesticide petitions as follows proposing the 
establishment and/or amendment of regulations for residues of certain 
pesticide chemicals 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 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 granting of the petitions. Additional data 
may be needed before EPA rules on the petitions.

List of Subjects

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

    Dated: November 29, 1999.

James Jones,

Director, Registration Division, Office of Pesticide Programs.

Summaries of Petitions

    The petitioner summaries of pesticide petitions are printed below 
as required by section 408(d)(3) of the FFDCA. The summaries of 
petitions was prepared by the petitioner and represents the views of 
the petitioner. EPA is publishing the petition summaries verbatim 
without editing them 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.

1. Interregional Research Project Number 4

 1E4019, 7E4857, and 9E6009

    EPA has received pesticide petitions (1E4019, 7E4857, and 9E6009) 
from the Interregional Research Project Number 4 (IR-4) New Jersey 
Agricultural Experiment Station, Rutgers University, New Brunswick, New 
Jersey 08903 proposing, under 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 tolerances for residues of the herbicide paraquat (1,1-
dimethyl-4,4'-bypyridinium) derived from the application of the 
dichloride salt (calculated as the cation) in or on the raw 
agricultural commodities (RAC) globe artichoke, dry peas, and persimmon 
at 0.05, 0.3, and 0.05 parts per million (ppm), respectively. EPA has 
determined that the petitions contain data or information regarding the 
elements set forth in section 408(d)(2) of the FFDCA; however, EPA has 
not fully evaluated the sufficiency of the submitted data at this time 
or whether the data support granting of the petitions. Additional data 
may be needed before EPA rules on the petitions. This notice includes a 
summary of the petitions prepared by Zeneca Ag Products, the 
registrant, 1800 Concord Pike, P.O. Box 15458, Wilmingtion, Delaware 
19850-5458.

[[Page 67907]]

A. Residue Chemistry

    1. Plant metabolism. The qualitative nature of the residue in 
plants is adequately understood based on studies depicting the 
metabolism of paraquat in carrots and lettuce following pre-emergence 
treatments and in potatoes and soybeans following desiccant treatment. 
The residue of concern in plants is the parent chemical, paraquat.
    2. Analytical method. An adequate analytical method (spectrometric 
method) has been accepted and published in the Pesticide Analytical 
Manual (PAM Vol. II) for the enforcement of tolerances in plant 
commodities.
    3. Magnitude of residues. Magnitude of residue data were collected 
from three sites in the major globe artichoke producing region of the 
United States. No residues exceed the proposed tolerance of 0.05 ppm, 
when globe artichokes are treated with 3.0 to 3.6 lb active ingredient/
acre (ai/acre) of paraquat applied as three applications directed 
between the rows at approximately 7-day intervals and the last 
application 1-day prior to harvest. Residue data have been obtained 
from Washington and Idaho which represent 91% of the dry pea production 
in the United States. Mature dry peas were treated once with paraquat 
at either 0.5 or 1.0 lb ai/acre of paraquat 7 days prior to harvest. 
The highest residue recovered in the dry pea was 0.25 ppm. The other 
treated samples all had residues of <ls-thn-eq> 0.2 ppm. IR-4 is 
requesting the establishment of a tolerance for persimmon based on the 
0.05 ppm tolerance established on guava. Applications of paraquat in 
persimmon would be the same as those in the Gramoxone Extra label for 
use on guava, utilizing a directed, postemergence application.

B. Toxicological Profile

    1. Acute toxicity. Acute toxicity studies conducted with the 45.6% 
paraquat dichloride technical concentrate give the following results: 
oral lethal dose (LD)<INF>50</INF> in the rat of 344 milligrams/
kilograms (mg/kg) (males) and 283 mg/kg (females) (Category II); dermal 
LD<INF>50</INF> in the rat of > 2,000 mg/kg for males and females 
(Category III); the primary eye irritation study showed corneal 
involvement with clearing within 17 days (Category II); and dermal 
irritation of slight erythema and edema at 72 hours (Category IV). 
Paraquat is not a dermal sensitizer. Acute inhalation studies conducted 
to EPA guideline with aerosolized sprays result in lethal concentration 
(LC)<INF>50</INF> of 0.6 to 1.4 <greek-m>g paraquat cation/L (Category 
I). However, since paraquat dichloride has no measurable vapor 
pressure; and hydraulic spray droplets are too large to be respirable, 
inhalation exposure is not a concern in practice.
    2. Genotoxicty. Paraquat dichloride was not mutagenic in the Ames 
test using Salmonella typhinurium strains TA1535, TA1538, TA98, and 
TA100; the chromosomal aberrations in the bone marrow test system; or 
in the dominant lethal mutagenicity study with CD-1 mice. Additionally, 
paraquat dichloride was negative for unscheduled DNA synthesis (UDS) in 
rat hepatocyctes in vitro and in vivo. Paraquat was weakly positive in 
the mouse lymphoma cell assay only in the presence of metabolic 
activation. Paraquat dichloride was weakly positive in mammalian cells 
(lymphocytes) and positive in the sister chromatid exchange (SCE) assay 
in Chinese hamster lung fibroblasts. Paraquat is non-mutagenic.
    3. Reproductive and developmental toxicity. A 3-generation 
reproduction study in rats fed diets containing 0, 25, 75, and 150 ppm 
(0, 1.25, 3.75 or 7.5 mg of paraquat cation/kg/day, respectively) 
showed no effect on body weight gain, food consumption and utilization, 
fertility and length of gestation of the F<INF>0</INF>, F<INF>1</INF>, 
and F<INF>2</INF> parents at any dose. The no observed adverse effect 
level (NOAEL) and lowest observed adverse effect level (LOAEL) for 
systemic toxicity are 25 ppm (1.25 mg/kg/day) and 75 ppm (3.75 mg/kg/
day), respectively, expressed as paraquat cation, based on high 
mortality due to lung damage. The NOAEL for reproductive toxicity is 
<gr-thn-eq> 150 ppm [7.5 mg/kg/day; highest dose tested (HDT)] 
expressed as paraquat cation, as there were no reproductive effects 
observed.
    Two developmental toxicity studies were conducted in rats given 
gavage doses of 0, 1, 5, or 10 mg/kg/day and 0, 1, 3, or 8 mg/kg/day, 
respectively, expressed as paraquat cation. In the first study, the 
NOAEL for maternal toxicity was 1 mg/kg/day based on clinical signs of 
toxicity and decreased body weight gain at 5 mg/kg/day (the LOAEL). The 
NOAEL for developmental toxicity was set at 5 mg/kg/day based on 
delayed ossification of the forelimb and hindlimb digits. In the second 
study, the maternal and developmental NOAEL is 8 mg/kg/day HDT as there 
were no effects observed at any dose level. Based on both studies, the 
overall NOAEL for maternal and developmental toxicity is at least 3 mg/
kg/day.
    Two developmental toxicity studies were conducted in mice given 
gavage doses of 0, 1, 5, or 10 mg/kg/day and 0, 7.5, 15, or 25 mg/kg/
day paraquat ion, respectively. In the first study, the NOAEL and LOAEL 
for maternal toxicity are 5 mg/kg/day and, 10 mg/kg/day, respectively, 
based on reductions in body weight gain and death (range-finding 
study). The NOAEL and LOAEL for developmental toxicity are 5 mg/kg/day 
and 10 mg/kg/day, respectively based on an increased number of litters 
and fetuses with partial ossification of the 4th sternebra at 10 mg/kg/
day HDT. Both the maternal and developmental NOAELs are at 15 mg/kg/day 
in the second study. The maternal LOAEL of 25 mg paraquat cation/kg/day 
is based on death, decreases in body weight and body weight gain, and 
other clinical signs. The developmental LOAEL of 25 mg/kg/day is based 
on decreases in mean fetal weights, retarded ossification and other 
skeletal effects. According to the registrant, the developmental/
maternal NOAEL should be based on the second study and is 15 mg/kg/day. 
Paraquat dichloride is not a developmental toxin.
    4. Subchronic toxicity. A 90-day feeding study in dogs fed doses of 
0, 7, 20, 60, or 120 ppm with a NOAEL of 20 ppm based on lung effects 
such as alveolitis and alveolar collapse seen at the LOAEL of 60 ppm. A 
21-day inhalation toxicity study in rats were exposed to respirable 
aerosols of paraquat at doses of 0, 0.01, 0.1, 0.5, or 1.0 <greek-m>g/L 
with a NOAEL of 0.01 <greek-m>g/L and a LOAEL of 0.10 <greek-m>g/L 
based on histopathological changes to the epithelium of the larynx and 
nasal discharge.
    5. Chronic toxicity. In a 12-month feeding study in dogs fed dose 
levels of 0, 15, 30, or 50 ppm, expressed as paraquat cation. These 
levels corresponded to 0, 0.45, 0.93, or 1.51 mg of paraquat cation/kg/
day, respectively, in male dogs or 0, 0.48, 1.00, or 1.58 mg of 
paraquat cation/kg/day, respectively for female dogs. There was a dose-
related increase in the severity and extent of chronic pneumonitis in 
the mid-dose and high-dose male and female dogs. This effect was also 
noted in the low-dose male group, but was minimal when compared with 
the male controls. The systemic NOAEL is 15 ppm (0.45 mg/kg/day for 
males and 0.48 mg/kg/day for females, expressed as parquet cation). The 
systemic LOAEL is 30 ppm (0.93 mg/kg/day for males and 1.00 mg/kg/day 
for females, expressed as paraquat cation).
    In a 2-year chronic feeding/carcinogenicity study, rats were fed 
doses of paraquat dichloride at 0, 25, 75, or 150 ppm which correspond 
to 0, 1.25, 3.75, or 7.5 mg of paraquat cation/kg/day. Paraquat 
enhanced the development of ocular lesions in all of the treated 
groups. The predominant lesions detected opthalmoscopically

[[Page 67908]]

were lenticular opacities and cataracts. At test week 103, dose-related 
statistically significant (P < 0.001) increases in the incidence of 
ocular lesions were observed only in the mid-dose and high-dose male 
and female groups. Based on these findings, the NOAEL (approximate) and 
the LOAEL for systemic toxicity, for both sexes, are 25 ppm (1.25 mg/
kg/day) and 75 ppm (3.75 mg/kg/day), respectively.
    In another 2-year chronic feeding/carcinogenicity study, rats were 
dosed at 0, 6, 30, 100, or 300 ppm, expressed as paraquat dichloride 
(nominal concentrations), equivalent to 0, 0.25, 1.26, 4.15, or 12.25 
mg/kg/day, respectively (males) and 0, 0.30, 1.5, 5.12 or 15.29 mg/kg/
day respectively (females), expressed as paraquat dichloride. The 
incidence of ocular changes were low and not caused by paraquat in this 
study. The systemic NOAEL is 100 ppm of paraquat dichloride (4.15 and 
5.12 mg/kg/day, for males and females, respectively); or 3.0 mg/kg/day 
(males) and 3.7 mg/kg/day (females), expressed as paraquat cation. The 
systemic LOAEL is 300 ppm of paraquat dichloride (12.25 and 15.29 mg/
kg/day, for males and females, respectively); or 9.0 mg/kg/day (males) 
and 11.2 mg/kg/day (females), expressed as paraquat cation.
    A chronic feeding/carcinogenicity study in rats fed dose levels of 
0, 25, 75, or 150 ppm, expressed as paraquat cation (nominal 
concentrations). These doses corresponded to 0, 1.25, 3.75, or 7.5 mg 
paraquat cation/kg/day, respectively. There was uncertain evidence of 
carcinogenicity (squamous cell carcinomas in the head region; ears, 
nasal cavity, oral cavity and skin) in males at 7.5 mg/kg/day HDT with 
a systemic NOAEL of 1.25 mg/kg/day. Upon submission of additional data 
to EPA, the incidence of pulmonary adenomas and carcinomas was well 
within historical ranges and it was determined that paraquat was not 
carcinogenic in the lungs and head region of the rat.
    In another chronic feeding/carcinogenicity study, rats were fed 
dose levels of 0, 6, 30, 100, or 300 ppm, expressed as paraquat 
dichloride. There were no carcinogenic findings in this study at the 
HDT. In a 2-year chronic feeding/concinogenicity study, SPF Swiss 
derived mice were fed paraquat dichloride at dose levels of 0, 12.5, 
37.5, or 100/125 ppm, expressed as paraquat cation. These rates 
correspond to 0, 1.87, 5.62, and 15 mg/kg/day as cation. Because no 
toxic signs appeared after 35 weeks of dosing, the 100 ppm level was 
increased to 125 ppm at week 36. There were no carcinogenic effects 
observed in this study. The systemic NOAEL for both sexes is 12.5 ppm 
(1.87 mg/kg/day) and the systemic LOAEL is 37.5 ppm (5.6 mg/kg/day), 
each expressed as paraquat cation based on renal tubular degeneration 
in males and weight loss and decreased food intake in females.
    Paraquat is classified Category E for carcinogenicity (no evidence 
of carcinogenicity in animal studies).
    6. Animal metabolism. The qualitative nature of the residue in 
animals is adequately understood based on the combined studies 
conducted with ruminants (goats and cows), swine, and poultry. The 
residue of concern in eggs, milk, and poultry and livestock tissues is 
the parent, paraquat.

C. Aggregate Exposure

    In examining aggregate exposure, FQPA directs EPA to take into 
account available information concerning exposures from the pesticide 
residue in food and all other exposures for which there is reliable 
information. These other sources of exposure include drinking water, 
and non-occupational exposures, e.g., to pesticides used in and around 
the home. For estimating acute and chronic risks the Agency considers 
aggregate exposures from the diet and from drinking water. Exposures 
from uses in and around the home that may be short term, intermediate, 
or other durations may also be aggregated as appropriate for specific 
chemicals.
    1. Dietary exposure. For purposes of assessing the potential 
dietary exposure under the proposed tolerance, Zeneca has estimated 
aggregate exposure based on the tolerance levels of 0.05 ppm, 0.3 ppm, 
and 0.05 ppm in or on globe artichokes, dry peas, and persimmons and 
from all other established tolerances. Percent crop treated was also 
incorporated into the assessment to derive an upper bound anticipated 
residue contribution (ARC). The registrant has concluded that there are 
no acute endpoints of concern for paraquat, and an acute aggregate 
assessment is not required. The chronic population adjusted dose (cPAD) 
for chronic dietary assessments is 0.0045 mg/kg/day, based on a NOAEL 
of 0.45 mg/kg/day from a 1-year dog study and the addition of a 
standard uncertainty factor of 100.
    i. Food--chronic dietary assessment. A chronic dietary exposure 
analysis was performed using current and reassessed tolerance level 
residues, contributions from the proposed tolerance for use on globe 
artichoke, cotton, and persimmons and current percent crop treated 
information to estimate the ARC for the general population and 22 
subgroups. The tolerance in globe artichoke resulted in a ARC of 
0.0000001 mg/kg/day (0.002% of the cPAD) for the general population. 
The resulting ARC for the general U.S. population from all established 
uses is 0.000367 mg/kg/day (8.2% of the cPAD). For children ages 1-6, 
the most highly exposed subgroup, the resulting ARC is 0.001077 mg/kg/
day (23.9% of the cPAD).
    ii. Acute dietary assessment. The registrant has determined that 
current data on paraquat shows no acute dietary endpoint of concern. 
Therefore, an acute dietary risk assessment was not conducted for 
paraquat.
    iii. Drinking water . The Registration Eligibility Document (RED) 
for paraquat has stated the following:
    Paraquat is not expected to be a contaminant of ground water. 
Paraquat dichloride binds strongly to soil clay particles and it did 
not leach from the surface in terrestrial field dissipation studies. 
There were, however, detections of paraquat in drinking water wells 
from two states cited in the Pesticides in Ground Water Database 
(1991). These detections are not considered to be representative of 
normal paraquat use. Therefore, paraquat is not expected to be a ground 
water contaminant or concern based on normal use patterns. Due to its 
persistent nature, paraquat could potentially be found in surface water 
systems associated with soil particles carried by erosion; however, 
paraquat is immobile in most soils, and at very high application rates 
(50-1,000x), there was no desorption of paraquat from soils. Based on 
paraquat's normal use patterns and unique environmental fate 
characteristics, exposures to paraquat in drinking water are not 
expected to be obtained from surface water sources. Therefore, the only 
exposures considered in aggregate risk assessment for paraquat is 
chronic dietary.
    2. Non-dietary exposure. Paraquat dichloride has no residential or 
other non-occupational uses that might result in non-occupational, non-
dietary exposure for the general population. Paraquat products are 
Restricted Use, for use by Certified Applicators only, which means the 
general public cannot buy or use paraquat products.

D. Cumulative Effects

    In assessing the potential risk from cummulative effects of 
paraquat and other chemical substances, the Agency has considered 
structural similarities that exist between paraquat and other 
bipyridylium compounds such as diquat dibromide. Examination of the 
toxicology data bases of paraquat and diquat dibromide, indicates that 
the two compounds have clearly different target

[[Page 67909]]

organs. Based on available data, the registrant does not believe that 
the toxic effects produced by paraquat would be cumulative with those 
of diquat dibromide.

E. Safety Determination

    1. U.S. population. Based on the Paraquat RED, the only exposure 
route of concern for paraquat is chronic dietary. Using the 
conservation assumptions presented earlier, EPA has established a cPAD 
of 0.0045 mg/kg/day. This was based on the NOAEL for the 1-year dog 
study of 0.45 mg/kg/day and employed a 100-fold uncertainty factor. 
Results of this aggregate exposure assessment, which includes EPA's 
reassessment of tolerances for existing crops and the tolerance for use 
on globe artichokes, dry peas, and persimmons utilize 8.2% of the cPAD. 
Generally, exposures below 100% of the cPAD are of no concern because 
it represents the level at or below which daily aggregate dietary 
exposure over a lifetime will not pose appreciable risk to human 
health. Thus, the registrant has concluded that there is reasonable 
certainty that no harm will result from aggregate exposures to paraquat 
residues.
    2. Infants and children. Zeneca has determined that the established 
tolerances for paraquat, with amendments and changes as specified in 
this notice, meet the safety standards under the FQPA amendments to 
section 408(b)(2)(C) for infants and children. The safety determination 
for infants and children considers the factors noted above for the 
general population, but also takes into account the possibility of 
increased dietary exposure due to specific consumption patterns of 
infants and children, as well as the possibility of increased 
susceptibility to the toxic effects of paraquat residues in this 
population subgroup.
    In determining whether or not infants and children are particularly 
susceptible to toxic effects from paraquat residues, Zeneca considered 
the completeness of the data base for developmental and reproductive 
effects, the nature and severity of the effects observed, and other 
information.
    Based on the current data requirements, paraquat has a complete 
data base for developmental and reproductive toxicity. In the 
developmental studies, effects were seen (delayed ossification in the 
forelimb and hindlimb digits) in the fetuses only at the same or higher 
dose levels than effects in the mother. In the reproduction study, no 
effects on reproductive performance were seen. Also because the NOAELs 
from the developmental and reproduction studies were equal to or 
greater than the NOAEL used for establishing the cPAD, the registrant 
concluded that it is unlikely that there is additional risk concern for 
immature or developing organisms. Finally, there is no epidemiological 
information suggesting special sensitivity of infants and children to 
paraquat. Therefore, the registrant found that an additional safety 
factor for infants and children is not warranted for paraquat.
    Zeneca estimates that paraquat residues in the diet of non-nursing 
infants (less than 1-year) account for 17.6% of the cPAD and 23.9% of 
the cPAD for children aged 1-6 years. Further, residues in drinking 
water are not expected. Therefore, Zeneca has determined that there is 
reasonable certainty that dietary exposure to paraquat will not cause 
harm to infants and children.

F. International Tolerances

    There is no approved CODEX maximum residue level (MRL) established 
for residues of paraquat on globe artichokes, dry peas, and persimmons.


[FR Doc. 99-31442 Filed 12-2-99; 8:45 am]
BILLING CODE 6560-50-F