[Federal Register Volume 65, Number 98 (Friday, May 19, 2000)]
[Notices]
[Pages 31904-31908]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-12651]


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ENVIRONMENTAL PROTECTION AGENCY

[PF-943; FRL-6558-2]


Notice of Filing a Pesticide Petition 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 a pesticide 
petition 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-943, must be 
received on or before June 19, 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. To ensure 
proper receipt by EPA, it is imperative that you identify docket 
control number PF-943 in the subject line on the first page of your 
response.

FOR FURTHER INFORMATION CONTACT:  By mail: Joanne I. Miller, 
Registration Division (7505C), Office of Pesticide Programs, 
Environmental Protection Agency, Ariel Rios Bldg., 1200 Pennsylvania 
Ave., NW., Washington, DC 20460; telephone number: (703) 305-6224; e-
mail address: <a href="/cdn-cgi/l/email-protection#1d70747171786f3377727c7373785d786d7c337a726b"><span class="__cf_email__" data-cfemail="2f424643434a5d0145404e41414a6f4a5f4e01484059">[email protected]</span></a>.

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 under FOR FURTHER INFORMATION 
CONTACT.

B. How Can I Get Additional Information, Including Copies of this 
Document and Other Related Documents?

    1. Electronically. You may obtain electronic copies of this 
document, and certain other related documents that might be available 
electronically, from the EPA Internet Home Page at http://www.epa.gov/. 
To access this document, on the Home Page select ``Laws and 
Regulations'' 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-943. The official record 
consists of the documents specifically referenced in this action, any 
public comments received during an applicable comment period, and other 
information related to this action, including any information claimed 
as confidential business information (CBI). This official record 
includes the documents that are physically located in the docket, as 
well as the documents that are referenced in those documents. The 
public version of the official record does not include any

[[Page 31905]]

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-943 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, Ariel Rios Bldg., 1200 Pennsylvania Ave., NW., Washington, DC 
20460.
    2. In person or by courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Information Resources 
and Services Division (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, Rm. 119, Crystal Mall #2, 1921 
Jefferson Davis Highway, Arlington, VA. The PIRIB is open from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.
    3.Electronically. You may submit your comments electronically by e-
mail to: ``<a href="/cdn-cgi/l/email-protection#a9c6d9d984cdc6cac2ccdde9ccd9c887cec6df"><span class="__cf_email__" data-cfemail="3f504f4f125b505c545a4b7f5a4f5e11585049">[email protected]</span></a>,'' 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-943. Electronic comments may 
also be filed online at many Federal Depository Libraries.

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

    Do not submit any information electronically that you consider to 
be CBI. You may claim information that you submit to EPA in response to 
this document as CBI by marking any part or all of that information as 
CBI. Information so marked will not be disclosed except in accordance 
with procedures set forth in 40 CFR part 2. In addition to one complete 
version of the comment that includes any information claimed as CBI, a 
copy of the comment that does not contain the information claimed as 
CBI must be submitted for inclusion in the public version of the 
official record. Information not marked confidential will be included 
in the public version of the official record without prior notice. If 
you have any questions about CBI or the procedures for claiming CBI, 
please consult the person identified under FOR FURTHER INFORMATION 
CONTACT.

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

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

II. What Action is the Agency Taking?

    EPA has received a pesticide petition as follows proposing the 
amendment of the regulation for residues of glufosinate-ammonium, a 
pesticide chemical, in or on food commodities derived from cotton under 
section 408 of the Federal Food, Drug, and Comestic Act (FFDCA), 21 
U.S.C. 346a. EPA has determined that this request contains data or 
information regarding the elements set forth in section 408(d)(2); 
however, EPA has not evaluated 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.

List of Subjects

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

    Dated: May 9, 2000.
James Jones,
Director, Registration Division, Office of Pesticide Programs.

Summary of Petition

    The petitioner summary of the pesticide petition is printed below 
as required by section 408(d)(3) of the FFDCA. The summary of the 
petition was prepared by the petitioner and represents the view of the 
petitioners. EPA is publishing the petition summary verbatim without 
editing it in any way. The summary identifies an analytical method 
available to EPA for the detection and measurement of the residues of 
glufosinate-ammonium in or on cotton commodities.

Aventis CropScience USA

PP 0F6140

    EPA has received a pesticide petition (PP 0F6140) from Aventis 
CropScience USA, PO Box 12014, 2 T. W. Alexander Drive, Research 
Triangle Park, NC 27709, 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 180.473(a)(1) by establishing tolerances for residues 
of the herbicide glufosinate-ammonium (butanoic acid, 2-amino-4-
(hydroxymethylphosphinyl)-, monoammonium salt) and its metabolite, 3-
methylphosphinico-propionic acid, expressed as 2-amino-4-
(hydroxymethylphosphinyl)butanoic acid equivalents in or on the raw 
agricultural commodities derived from cotton: undelinted seed at 3.5 
parts per million (ppm) and gin byproducts at 12.0 ppm. Aventis 
CropScience also proposes to amend 40 CFR part 180.473(c) by 
establishing tolerances for residues of the herbicide glufosinate-
ammonium (butanoic acid, 2-amino-4-(hydroxymethylphosphinyl)-, 
monoammonium salt) and its metabolites, 3-methylphosphinico-propionic 
acid, and 2-acetamido-4-methylphosphinico-butanoic acid expressed as 2-
amino-4-(hydroxymethylphosphinyl)butanoic acid equivalents in or on the 
raw agricultural commodities derived from transgenic cotton tolerant to 
glufosinate-ammonium: Undelinted seed at 3.5 ppm and gin byproducts at 
12.0 ppm. EPA has determined that the petition contains data or 
information regarding the elements set forth in section 408(d)(2) of 
the FFDCA; however, EPA has not fully evaluated the sufficiency of the 
submitted data at this time or whether the data supports granting of

[[Page 31906]]

the petition. Additional data may be needed before EPA rules on the 
petition.

A. Residue Chemistry

    1. Plant metabolism. The metabolism of glufosinate-ammonium in 
plants has been investigated and is understood. The crop residue 
profile following selective use of glufosinate-ammonium on transgenic 
crops is different from that found in conventional crops. The crop 
residue observed after non-selective use is the metabolite 3-
methylphosphinico-propionic acid which is found only in trace amounts. 
The principal residue identified in the metabolism studies after 
selective use of glufosinate-ammonium on transgenic crops is the 
acetylated derivative of parent material, 2-acetamido-4-
methylphosphinico-butanoic acid with lesser amounts of 3-
methylphosphinico-propionic acid observed.
    2. Analytical method. The enforcement analytical method utilizes 
gas chromatography for detecting and measuring levels of glufosinate-
ammonium and metabolites with a general limit of quantification of 0.05 
ppm. This method allows detection of residues at or above the proposed 
tolerances.
    3. Magnitude of residues. Field residue trials were conducted 
across the five major regions of cotton production in the U.S. Two 
different treatment regimes were examined to represent use patterns 
which are the most likely to result in the highest residues. 
Glufosinate-ammonium derived residues did not exceed 3.4 ppm in 
undelinted cotton seed and 11.6 ppm in cotton gin byproducts (trash) 
when sampled at 70 days or more after the last treatment. No 
significant concentration of the residues occurred in the processed 
cotton commodities meal and hull and in refined oil the residues were 
less than the limit of quantitation (LOQ) of the analytical method. 
Thus, tolerances are not being proposed for the processed commodities 
from cotton.

B. Toxicological Profile

    1. Acute toxicity. Glufosinate-ammonium has been classified as 
toxicity category III for acute oral, dermal and inhalation toxicity. 
It is toxicity category III for eye irritation. It is not a dermal 
irritant (toxicity category IV) nor is it a dermal sensitizer. The oral 
LD<INF>50</INF> is 2 gram/kilogram (g/kg) in male rats and 1.62 g/kg in 
female rats.
    2. Genotoxicity. Based on results of a complete genotoxicity 
database, there is no evidence of mutagenic activity in a battery of 
studies, including: Salmonella spp., E. coli, in vitro mammalian cell 
gene mutation assays, mammalian cell chromosome aberration assays, in 
vivo mouse bone marrow micronucleus assays, and unscheduled DNA 
synthesis assays.
    3. Reproductive and developmental toxicity. In a developmental 
toxicity study, groups of 20 pregnant female Wistar rats were 
administered glufosinate-ammonium by gavage at doses of 0, 0.5, 2.24 
10, 50 and 250 mg/kg/day from days 7 to 16 of pregnancy. The no 
observed adverse effect level (NOAEL) for maternal toxicity is 10 mg/
kg/day; the lowest observed adverse effect level (LOAEL) is 50 mg/kg/
day based on vaginal bleeding and hyperactivity in dams. In the fetus, 
the NOAEL is 50 mg/kg/day, based on dilated renal pelvis observations 
at the LOAEL of 250 mg/kg/day.
    In a developmental toxicity study, groups of 15 pregnant female 
Himalayan rabbits were administered glufosinate-ammonium by gavage at 
doses of 0, 2.0, 6.3 or 20.0 millgrams/kilogram/day (mg/kg/day) from 
days 7 to 19 of pregnancy. In maternal animals, decreases in food 
consumption and body weight gain were observed at the 20 mg/kg/day dose 
level. The NOAEL for both maternal and developmental toxicity was 6.3 
mg/kg/day.
    In a multi-generation reproduction study, glufosinate-ammonium was 
administered to groups of 30 male and 30 female Wistar/Han rats in the 
diet at concentrations of 0, 40, 120 or 360 ppm. The LOAEL for systemic 
toxicity is 120 ppm based on increased kidney weights in both sexes and 
generations. The systemic toxicity NOAEL is 40 ppm. The LOAEL for 
reproductive/developmental toxicity is 360 ppm based on decreased 
numbers of viable pups in all generations. The NOAEL is 120 ppm.
    4. Subchronic toxicity. In a sub-chronic oral toxicity study, 
glufosinate-ammonium was administered to 10 NMRI mice/sex/ dose in the 
diet at levels of 0, 80, 320 or 1,280 ppm (equivalent to 0, 12, 48, or 
192 mg/kg/day) for 13 weeks. Significant (p< 0.05) increases were 
observed in serum aspartate aminotransferase and in alkaline 
phosphatase in high-dose (192 mg/kg/day) males. Also observed were 
increases in absolute and relative liver weights in mid-(48 mg/kg/day) 
and high-dose males. The NOAEL is 12 mg/kg/day, the LOAEL is 48 mg/kg/
day based on the changes in clinical biochemistry and liver weights.
    5. Chronic toxicity. In a combined chronic toxicity/oncogenicity 
study, glufosinate-ammonium was administered to 50 Wistar rats/sex/dose 
in the diet for 130 weeks at dose levels of 0, 40, 140, or 500 ppm 
(mean compound intake in males was 0, 1.9, 6.8, and 24.4 mg/kg/day and 
for females was 0, 2.4, 8.2 and 28.7 mg/kg/day, respectively). A dose-
related increase in mortality was noted in females at 140 and 500 ppm, 
whereas in males increased absolute and relative kidney weights were 
noted at 140 ppm and 500 ppm. The NOAEL was considered to be 40 ppm. No 
treatment-related oncogenic response was noted.
    In an oncogenicity study, glufosinate-ammonium was administered to 
50 NMRI mice/sex/dose in the diet at dose levels of 0, 80, 160 (males 
only) or 320 (females only) ppm for 104 weeks. The NOAEL for systemic 
toxicity is 80 ppm (10.82/16.19 mg/kg/day in males/females (M/F)), and 
the LOAEL is 160/320 ppm (22.60/63.96 mg/kg/day in M/F), based on 
increased mortality in males, increased glucose levels in males and 
females, and changes in glutathione levels in males. No increase in 
tumor incidence was found in any treatment group.
    In a chronic feeding study, glufosinate-ammonium technical was fed 
to male and female beagle dogs for 12 months in the diet at levels of 
2.0, 5.0 or 8.5 mg/kg/day. The NOAEL is 5.0 mg/kg/day based on clinical 
signs of toxicity, reduced weight gain and mortality 8.5 mg/kg/day.
    In a rat oncogenicity study, glufosinate-ammonium was administered 
to Wistar rats (60/sex/group) for up to 24 months at 0, 1,000, 5,000, 
or 10,000 ppm (equivalent to 0, 45.4, 228.9, or 466.3 mg/kg/day in 
males and 0, 57.1, 281.5, or 579.3 mg/kg/day in females). The LOAEL for 
chronic toxicity is 5,000 ppm (equivalent to 228.9 mg/kg/day for male 
rats and 281.5 mg/kg/day for females), based on increased incidences of 
retinal atrophy. The chronic NOAEL is 1,000 ppm. Under the conditions 
of this study, there was no evidence of carcinogenic potential. Dosing 
was considered adequate based on the increased incidence of retinal 
atrophy.
    6. Animal metabolism. Studies conducted in rats using 
<SUP>14</SUP>C-glufosinate-ammonium have shown that the compound is 
poorly absorbed (5-10%) after oral administration and is rapidly 
eliminated primarily as the parent compound. The highest residue levels 
were found in liver and kidney tissues.
    The metabolic profile and the quantitative distribution of 
metabolites was very similar in both goat and hen. The vast majority of 
the dose was excreted, primarily as parent compound. The very limited 
residues found in edible tissues, milk and eggs were comprised 
principally of glufosinate and 3-methylphosphinico-

[[Page 31907]]

propionic acid (Hoe 061517), with lesser amounts of N-acetyl-L-
glufosinate (Hoe 099730) and 2-methylohosphinico-acetic acid (Hoe 
064619).
    7. Metabolite toxicology. Additional testing has been conducted 
with the major metabolites, Hoe 061517 and Hoe 099730, as well as the 
L-isomer of glufosinate-ammonium, identified as Hoe 058192. Based on 
sub-chronic and developmental toxicity study results, a profile of 
similar or less toxicity compared to the parent compound, glufosinate-
ammonium, was observed.
    8. Endocrine disruption. No special studies have been conducted to 
investigate the potential of glufosinate-ammonium to induce estrogenic 
or other endocrine effects. However, no evidence of estrogenic or other 
endocrine effects have been noted in any of the toxicology studies that 
have been conducted with this product and there is no reason to suspect 
that any such effects would be likely.

C. Aggregate Exposure

    1. Dietary exposure. Tolerances have been established (40 CFR part 
180.473) for the combined residues of glufosinate-ammonium and 
metabolites in or on a variety of raw agricultural commodities. No 
appropriate toxicological endpoint attributable to a single exposure 
was identified in the available toxicity studies. EPA, therefore, has 
no, established an acute reference dose (RfD) for the general 
population including infants and children. An acute RfD of 0.063 mg/kg/
day was established, however, for the females 13+ subgroup. An acute 
analysis was conducted for the sub-population of females 13+. Chronic 
dietary analysis was conducted for the usual populations.
    i. Food. An acute dietary analysis was conducted using the Dietary 
Exposure Evaluation Model (DEEM) software and the 1994-1996 CSFII 
consumption data base. The analysis assumed tolerance level residues 
for all commodities and 100% of crop treated. This Tier One analysis 
resulted in an exposure of 0.007432 mg/kg bw/day (95th percentile) for 
the female 13+ sub-population (the only population of concern) 
representing 35% utilization of the acute reference dose (RfD).
    Chronic dietary analysis was conducted to estimate exposure to 
potential glufosinate-ammonium residues in or on registered and 
proposed commodities. The DEEM software and the 1994-1996 USDA food 
consumption data were used. Tolerance level residues were assumed for 
all commodities and conservative percent crop treated values were 
incorporated for major crops (25% corn, 15% soybean, 10% potatoes, 20% 
cotton), whereas 100% of the crop was assumed to be treated for all 
other registered or pending uses. Chronic dietary exposure estimates 
from residues of glufosinate-ammonium for the US Population utilized 
approximately 25% of the chronic RfD. The sub-population with the 
highest exposure was children 1-6 utilizing approximately 67% of the 
chronic RfD. This analysis was based on highly conservative 
assumptions. The Agency has no concerns with RfD utilization up to 
100%.
    ii. Drinking water. US EPA's Standard Operating Procedure (SOP) for 
Drinking Water Exposure and Risk Assessments was used to perform the 
drinking water assessment. The models screening concentrations in 
ground water (SCI-GROW) and EPA's Pesticide Root Zone Model (PRZM)-
EXAMS were used to estimate the concentration of glufosinate-ammonium 
which might occur in water. The acute drinking water level of 
comparison (DWLOC) for females 13+ is 408 parts per billion (ppb). In 
comparison, the acute drinking water estimated concentrations (DWEC) 
calculated by Generic expected environmental concentration (GENEEC) is 
45 ppb, nearly an order of magnitude below the DWLOC.
    The chronic DWLOC calculated for adults is 184 ppb and that for 
children/toddlers is 24 ppb. The chronic DWEC calculated using a worst 
case scenario is 11 ppb (GENEEC). Thus, the drinking water estimated 
concentration represents only 11% of the DWLOC for adults and 46% of 
that for children/toddlers. The DWLOC are based on highly conservative 
dietary (food) exposures and are expected to be much higher in real 
world situations reducing further the percent utilization of the DWLOC 
even more favorable.
    2. Non-dietary exposure. Glufosinate-ammonium is currently 
registered for use on the following non-food sites: areas around 
ornamentals, shade trees, Christmas trees, shrubs, walks, driveways, 
flower beds, farmstead buildings, in shelter belts, and along fences. 
It is also registered for use as a post-emergent herbicide on 
farmsteads, areas associated with airports, commercial plants, storage 
and lumber yards, highways, educational facilities, fence lines, ditch 
banks, dry ditches, schools, parking lots, tank farms, pumping 
stations, parks, utility rights-of-way, roadsides, railroads, and other 
public areas and similar industrial and non-food crop areas. It is also 
registered for lawn renovation uses.
    The EPA has determined that there are no acute or chronic non-
dietary exposure scenarios. Further, the Agency has determined that it 
is not appropriate to aggregate short- and intermediate-term non-
dietary exposure with dietary exposures in risk assessments because the 
end-points are different.

D. Cumulative Effects

    Section 408(b)(2)(D)(v) requires that, when considering whether to 
establish, modify, or revoke a tolerance, the Agency consider 
``available information'' concerning the cumulative effects of a 
particular pesticide's residues and ``other substances that have a 
common mechanism of toxicity.'' EPA has indicated that, at this time, 
the Agency does not have available data to determine whether 
glufosinate-ammonium has a common mechanism of toxicity with other 
substances or how to include this pesticide in a cumulative risk 
assessment. Unlike other pesticides for which EPA has followed a 
cumulative risk approach based on a common mechanism of toxicity, 
glufosinate-ammonium does not appear to produce a toxic metabolite 
produced by other substances. For the purposes of this tolerance 
petition, therefore, it has not been assumed that glufosinate-ammonium 
has a common mechanism of toxicity with other substances.

E. Safety Determination

    1. U.S. population. Using the conservative assumptions described 
above, based on the completeness and reliability of the toxicity data, 
it is concluded that chronic dietary exposure to the registered and 
proposed uses of glufosinate-ammonium will utilize at most 25% of the 
chronic RfD for the US Population. The actual exposure is likely to be 
much less as more realistic data and models are developed. Exposures 
below 100% of the RfD are generally assumed to be of no concern because 
the RfD represents the level at or below which daily aggregate exposure 
over a lifetime will not pose appreciable risk to human health.
    The acute population of concern, female 13+ utilizes 35% of the 
acute RfD. This is a Tier One highly conservative assessment and actual 
exposure is likely to be far less. DWLOC based on dietary exposures are 
greater than highly conservative estimated levels, and would be 
expected to be well below the 100% level of the RfD, if they occur at 
all.
    EPA has concluded that it is not appropriate to aggregate non-
dietary exposures with dietary exposures in a risk assessment because 
the toxicity end-points are different.
    Therefore, there is a reasonable certainty that no harm will occur 
to the

[[Page 31908]]

US Population from aggregate exposure (food, drinking water and 
nonresidential) to residues of glufosinate-ammonium and metabolites.
    2. Infants and children. The toxicological data base is sufficient 
for evaluating prenatal and postnatal toxicity for glufosinate-
ammonium. There are no prenatal or postnatal susceptibility concerns 
for infants and children, based on the results of the rat and rabbit 
developmental toxicity studies and the 2-generation reproduction study. 
Based on clinical signs of neurological toxicity in short and 
intermediate dermal toxicity studies with rats, EPA has determined that 
an added FQPA safety factor of 3x is appropriate of assessing the risk 
of glufosinate-ammonium derived residues in crop commodities.
    Using the conservative assumptions described in the exposure 
section above, the percent of the chronic reference dose that will be 
used for exposure to residues of glufosinate-ammonium in food for 
children 1-6 (the most highly exposed sub group) is 67%. Infants 
utilize 43% of the chronic RfD. As in the adult situation, DWLOC are 
higher than the worst case drinking water estimated concentrations and 
are expected to use well below 100% of the RfD, if they occur at all.
    Therefore, there is a reasonable certainty that no harm will occur 
to infants and children from aggregate exposure to residues of 
glufosinate-ammonium.

F. International Tolerances

    Maximum residue limits (Codex MRLs) for glufosinate-ammonium and 
metabolites in or on cotton commodities have not been established by 
the Codex Alimentarius Commission.
[FR Doc. 00-12651 Filed 5-18-00; 8:45 am]
BILLING CODE 6560-50-F


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