[Federal Register: August 18, 2004 (Volume 69, Number 159)]
[Notices]
[Page 51301-51312]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18au04-60]
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ENVIRONMENTAL PROTECTION AGENCY
[OPP-2004-0160; FRL-7364-6]
Glyphosate; Notice of Filing a Pesticide Petition to Establish a
Tolerance for a Certain Pesticide Chemical in or on Food
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice.
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SUMMARY: This notice announces the initial filing of a pesticide
petition proposing the establishment of regulations for residues of a
certain pesticide chemical in or on various food commodities.
DATES: Comments, identified by docket identification (ID) number OPP-
2004-0160, must be received on or before September 17, 2004.
ADDRESSES: Comments may be submitted electronically, by mail, or
through hand delivery/courier. Follow the detailed instructions as
provided in Unit I. of the SUPPLEMENTARY INFORMATION.
FOR FURTHER INFORMATION CONTACT: James A. Tompkins, Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001; telephone number: (703) 305-5697; e-mail address:
tompkins.jim@epa.gov.
SUPPLEMENTARY INFORMATION:
I. General Information
A. Does this Action Apply to Me?
You may be potentially affected by this action if you an
agricultural producer, food manufacturer, or pesticide manufacturer.
Potentially affected entities may include, but are not limited to:
Crop production (NAICS 111)
Animal production (NAICS 112)
Food manufacturing (NAICS 311)
Pesticide manufacturing (NAICS 32532)
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 this unit could also be
affected. The North American Industrial Classification System (NAICS)
codes have been provided to assist you and others in determining
whether this action might apply to certain entities. If you have any
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 Copies of this Document and Other Related Information?
1. Docket. EPA has established an official public docket for this
action under docket ID number OPP-2004-0160. The official public docket
consists of the documents specifically referenced in this action, any
public comments received, and other information related to this action.
Although a part of the official docket, the public docket does not
include Confidential Business Information (CBI) or other information
whose disclosure is restricted by statute. The official public docket
is the collection of materials that is available for public viewing at
the Public Information and Records Integrity Branch (PIRIB), Rm. 119,
Crystal Mall 2, 1801 S. Bell St., Arlington, VA. This docket
facility is open from 8:30 a.m. to 4 p.m., Monday through Friday,
excluding legal holidays. The docket telephone number is (703) 305-
5805.
2. Electronic access. You may access this FederalRegister document
electronically through the EPA Internet under the ``Federal Register''
listings at http://www.epa.gov/fedrgstr/.
An electronic version of the public docket is available through
EPA's electronic public docket and comment system, EPA Dockets. You may
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public
comments, access the index listing of the contents of the official
public docket, and to access those documents in the public
[[Page 51302]]
docket that are available electronically. Although not all docket
materials may be available electronically, you may still access any of
the publicly available docket materials through the docket facility
identified in Unit I.B.1. Once in the system, select ``search,'' then
key in the appropriate docket ID number.
Certain types of information will not be placed in the EPA Dockets.
Information claimed as CBI and other information whose disclosure is
restricted by statute, which is not included in the official public
docket, will not be available for public viewing in EPA's electronic
public docket. EPA's policy is that copyrighted material will not be
placed in EPA's electronic public docket but will be available only in
printed, paper form in the official public docket. To the extent
feasible, publicly available docket materials will be made available in
EPA's electronic public docket. When a document is selected from the
index list in EPA Dockets, the system will identify whether the
document is available for viewing in EPA's electronic public docket.
Although not all docket materials may be available electronically, you
may still access any of the publicly available docket materials through
the docket facility identified in Unit I.B.1. EPA intends to work
towards providing electronic access to all of the publicly available
docket materials through EPA's electronic public docket.
For public commenters, it is important to note that EPA's policy is
that public comments, whether submitted electronically or in paper,
will be made available for public viewing in EPA's electronic public
docket as EPA receives them and without change, unless the comment
contains copyrighted material, CBI, or other information whose
disclosure is restricted by statute. When EPA identifies a comment
containing copyrighted material, EPA will provide a reference to that
material in the version of the comment that is placed in EPA's
electronic public docket. The entire printed comment, including the
copyrighted material, will be available in the public docket.
Public comments submitted on computer disks that are mailed or
delivered to the docket will be transferred to EPA's electronic public
docket. Public comments that are mailed or delivered to the docket will
be scanned and placed in EPA's electronic public docket. Where
practical, physical objects will be photographed, and the photograph
will be placed in EPA's electronic public docket along with a brief
description written by the docket staff.
C. How and to Whom Do I Submit Comments?
You may submit comments electronically, by mail, or through hand
delivery/courier. To ensure proper receipt by EPA, identify the
appropriate docket ID number in the subject line on the first page of
your comment. Please ensure that your comments are submitted within the
specified comment period. Comments received after the close of the
comment period will be marked ``late.'' EPA is not required to consider
these late comments. If you wish to submit CBI or information that is
otherwise protected by statute, please follow the instructions in Unit
I.D. Do not use EPA Dockets or e-mail to submit CBI or information
protected by statute.
1. Electronically. If you submit an electronic comment as
prescribed in this unit, EPA recommends that you include your name,
mailing address, and an e-mail address or other contact information in
the body of your comment. Also include this contact information on the
outside of any disk or CD ROM you submit, and in any cover letter
accompanying the disk or CD ROM. This ensures that you can be
identified as the submitter of the comment and allows EPA to contact
you in case EPA cannot read your comment due to technical difficulties
or needs further information on the substance of your comment. EPA's
policy is that EPA will not edit your comment, and any identifying or
contact information provided in the body of a comment will be included
as part of the comment that is placed in the official public docket,
and made available in EPA's electronic public docket. If EPA cannot
read your comment due to technical difficulties and cannot contact you
for clarification, EPA may not be able to consider your comment.
i. EPA Dockets. Your use of EPA's electronic public docket to
submit comments to EPA electronically is EPA's preferred method for
receiving comments. Go directly to EPA Dockets at http://www.epa.gov/edocket/
, and follow the online instructions for submitting comments.
Once in the system, select ``search,'' andthen key in docket ID number
OPP-2004-0160. The system is an ``anonymous access'' system, which
means EPA will not know your identity, e-mail address, or other contact
information unless you provide it in the body of your comment.
ii. E-mail. Comments may be sent by e-mail to opp-docket@epa.gov,
Attention: Docket ID number OPP-2004-0160. In contrast to EPA's
electronic public docket, EPA's e-mail system is not an ``anonymous
access'' system. If you send an e-mail comment directly to the docket
without going through EPA's electronic public docket, EPA's e-mail
system automatically captures your e-mail address. E-mail addresses
that are automatically captured by EPA's e-mail system are included as
part of the comment that is placed in the official public docket, and
made available in EPA's electronic public docket.
iii. Disk or CD ROM. You may submit comments on a disk or CD ROM
that you mail to the mailing address identified in Unit I.C.2. These
electronic submissions will be accepted in WordPerfect or ASCII file
format. Avoid the use of special characters and any form of encryption.
2. By mail. Send your comments to: Public Information andRecords
Integrity Branch (PIRIB) (7502C), Office of Pesticide Programs (OPP),
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460-0001, Attention: Docket ID number OPP-2004-0160.
3. By hand delivery or courier. Deliver your comments to: Public
Information and Records Integrity Branch (PIRIB), Office of Pesticide
Programs (OPP), Environmental Protection Agency, Rm. 119, Crystal Mall
2, 1801 S. Bell St., Arlington, VA, Attention: Docket ID
number OPP-2004-0160. Such deliveries are only accepted during the
docket's normal hours of operation as identified in Unit I.B.1.
D. How Should I Submit CBI to the Agency?
Do not submit information that you consider to be CBI
electronically through EPA's electronic public docket or by e-mail. You
may claim information that you submit to EPA as CBI by marking any part
or all of that information as CBI (if you submit CBI on disk or CD ROM,
mark the outside of the disk or CD ROM as CBI and then identify
electronically within the disk or CD ROM the specific information that
is (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 docket and EPA's electronic public docket. If you submit
the copy that does not contain CBI on disk or CD ROM, mark the outside
of the disk or CD ROM clearly that it does not contain CBI. Information
not marked as CBI will be included in the public docket and EPA's
electronic public docket without prior
[[Page 51303]]
notice. If you have any questions about CBI or the procedures for
claiming CBI, please consult the person listed 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
ID number assigned to this action in the subject line on the first page
of your response. You may also provide the name, date, and Federal
Register citation.
II. What Action is the Agency Taking?
EPA has received a pesticide petition as follows proposing the
establishment and/or amendment of regulations for residues of a certain
pesticide chemical in or on various food commodities under section 408
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a.
EPA has determined that this petition contains data or information
regarding the elements set forth in FFDCA section 408(d)(2); however,
EPA has not fully evaluated the sufficiency of the submitted data at
this time or whether the data support granting of the petition.
Additional data may be needed before EPA rules on the petition.
List of Subjects
Environmental protection, Agricultural commodities, Feed additives,
Food additives, Pesticides and pests, Reporting and recordkeeping
requirements.
Dated: August 9, 2004.
Betty Shackleford,
Acting Director, Registration Division, Office of Pesticide Programs.
Summary of Petition
The petitioner summary of the pesticide petition is printed below
as required by FFDCA section 408(d)(3). The summary of the petition was
prepared by the petitioner and represents the view of the petitioner.
The petition summary announces the availability of a description of the
analytical methods available to EPA for the detection and measurement
of the pesticide chemical residues or an explanation of why no such
method is needed.
Monsanto Company
PP 0F6195, 1F6273, 1F6274, and 3F6570
EPA has received pesticide petitions (0F6195, 1F6273, 1F6274, and
3F6570) from Monsanto Company, 600 13th St., NW., Suite 660,
Washington, DC 20005, 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 180.364 by establishing a regulation to permit residues of
the herbicide glyphosate (N-phosphonomethyl) glycine in or on the
following raw agricultural commodities:Alfalfa, seed at 0.5 parts per
million (ppm); rice, grain at 15.0 ppm; and cotton, gin by-products at
150 ppm; wheat, forage at 10.0 ppm, wheat, hay at 10.0 ppm; and the
following processed commodities: Rice, bran at 30.0 ppm; andrice, hulls
at 25.0 ppm. Monsanto further proposes to delete the entire entries for
alfalfa, forage at 175 ppm and alfalfa, hay at 400 ppm as these
tolerances are no longer needed, and to revise the entry for grain,
cereal group to read: Grain, cereal, group 15 except barley, field
corn, grain sorghum, oats, rice and wheat at 0.1 ppm. EPA has
determined that the petitions contain data or information regarding the
elements set forth in section 408(d)(2) of the FFDCA; however, EPA has
not fully evaluated the sufficiency of the submitted data at this time
or whether the data supports granting of the petitions. Additional data
may be needed before EPA rules on these petitions.
The petitions request that 40 CFR 180.364 be amended by
establishing tolerances for residues of the herbicide glyphosate in or
on alfalfa, seed at 0.5 ppm; rice, grain at 15. 0 ppm; rice, bran at
25.0 ppm; rice, hulls at 30.0 ppm; wheat, forage at 10.0 ppm; and
wheat, hay at 10.0 ppm, increasing the established tolerance for
cotton, gin by-products from 100 ppm to 150 ppm; by deleting the
tolerances for alfalfa, forage at 175 ppm and alfalfa, hay at 400ppm,
and by revising the grain, cereal group tolerance to ``except rice''
and read as follows: Grain, cereal group 15 except barley, field corn,
grain sorghum, oats, rice and wheat at 0.1 ppm. PP 0F6195 has been
amended to delete the proposal for wheat, grain at 6 ppm that was
announced earlier (May 17, 2002, 67 FR 18894) (FRL-6830-5). ``The
tolerances for alfalfa, rice, wheat, and cotton, gin by-products
include both conventional and genetically altered crops.'' It is also
proposed the 40 CFR 180.364 be amended by replacing the current listing
``Vegetable, legume group (except soybean) at 5.0 ppm with the current
crop group'' pea and bean, dried shelled, except soybean, subgroup 6C
at 5.0 ppm.
Section 408(b)(2)(A)(i) of the FFDCA allows EPA to establish a
tolerance (the legal limit for a pesticide chemical residue in or on a
food) only if EPA determines that the tolerance is ``safe.'' Section
408(b)(2)(A)(ii) defines ``safe'' to mean that ``there is a reasonable
certainty that no harm will result from aggregate exposure to the
pesticide chemical residue, including all anticipated dietary exposures
and all other exposures for which there is reliable information.'' This
includes exposure through drinking water and in residential settings,
but does not include occupational exposure. Section 408(b)(2)(C)
requires EPA to give special consideration to exposure of infants and
children to the pesticide chemical residue in establishing a tolerance
and to ``ensure that there is a reasonable certainty that no harm will
result to infants and children from aggregate exposure to the pesticide
chemical residue. . . .''
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 and a complete description of
the risk assessment process, see the final rule on Bifenthrin Pesticide
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).
A. Toxicological Profile
EPA has evaluated the available toxicity data and considered its
validity, completeness, and reliability as well as the relationship of
the results of the studies to human risk. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and
children. The nature of the acute toxic effects caused by glyphosate
are discussed in the following Table 1 as well as the no observed
adverse effect level (NOAEL) and the lowest observed adverse effect
level (LOAEL) from the toxicity studies reviewed in the following Table
2.
[[Page 51304]]
Table 1.--Acute Toxicity of Glyphosate Technical
------------------------------------------------------------------------
Guideline No. Study Type Results
------------------------------------------------------------------------
870.1100 Acute oral LD50 > 5,000 mg/kg
Toxicity Category
IV
------------------------------------------------------------------------
870.1200 Acute dermal LD50 > 5,000 mg/kg
Toxicity Category
IV
------------------------------------------------------------------------
870.1300 Acute inhalation The requirement
for an acute
inhalation LC50
study was waived
------------------------------------------------------------------------
870.2400 Primary eye Corneal opacity or
irritation irritation
clearing in 7
days or less
Toxicity Category
III
------------------------------------------------------------------------
870.2500 Primary skin Mild or slight
irritation irritant
Toxicity Category
IV
------------------------------------------------------------------------
870.2600 Dermal Not a dermal
sensitization sensitizer
------------------------------------------------------------------------
Table 2.--Toxicity Profile of Glyphosate Technical
------------------------------------------------------------------------
Guideline No. Study Type Results
------------------------------------------------------------------------
870.3100 90-Day oral NOAEL = 1,500 mg/
toxicity rodents kg/day in males
mouse and females
LOAEL = 4,500 mg/
kg/day in males
and females based
on decreased body
weight gain
------------------------------------------------------------------------
870.3100 90-Day oral NOAEL = < 50 mg/kg/
toxicity rodents day in males and
rat (range- female
finding) LOAEL = 50 mg/kg/
day in males and
females based on
increased
phosphorus and
potassium values
------------------------------------------------------------------------
870.3150 90-Day oral NOAEL = 400 mg/kg/
toxicity in day in males and
rodents rat females
(aminomethyl LOAEL = 1,200 mg/
phosphoric acid kg/day in males
plant metabolite and females based
of glyphosate) on body weight
loss and
histopathological
lesions of the
urinary bladder
------------------------------------------------------------------------
870.3485 28-Day inhalation NOAEL = 0.36 mg/L
toxicity - rat LOAEL = > 0.36
(exposure; 6 high dose tested
hours/day, 5 days/ (HDT) mg/L, not
week for 4 weeks) established
------------------------------------------------------------------------
870.3200 21-Day dermal NOAEL = 1,000 mg/
toxicity - rabbit kg/day in males
and females
LOAEL = 5,000 mg/
kg/day based on
slight erythema
and edema on
intact and
abraded skin of
both sexes, and
decreased food
consumption in
females
------------------------------------------------------------------------
870.3700 Prenatal Maternal
developmental in NOAEL = 1,000 mg/
rodents-rat kg/day
LOAEL = 3,500 mg/
kg/day based on
inactivity,
mortality,
stomach
hemorrhages and
reduced body
weight gain
Developmental
NOAEL = 1,000 mg/
kg/day
LOAEL = 3,500 mg/
kg/day based on
increased
incidence in the
number of fetuses
and litters with
unossified
sternebrae and
decreased fetal
body weight
------------------------------------------------------------------------
870.3700 Prenatal Maternal
developmental in NOAEL = 175 mg/kg/
nonrodents-rabbit day
LOAEL = 350 mg/kg/
day based on
mortality,
diarrhea, soft
stools, and nasal
discharge
Developmental
NOAEL = 350 mg/kg/
day
LOAEL = > mg/kg/
day, not
established
------------------------------------------------------------------------
[[Page 51305]]
870.3800 Reproduction and Parental/Systemic
fertility effects NOAEL = 30 mg/kg/
rat (3- day
generation) LOAEL = > 30 HDT
mg/kg/day, not
established
Reproductive
NOAEL = 30 mg/kg/
day
LOAEL = > 30 HDT
mg/kg/day, not
established
Offspring
NOAEL = 10 mg/kg/
day
LOAEL = 30 mg/kg/
day based on
focal dilation of
the kidney in
male F3b pups
------------------------------------------------------------------------
870.3800 Reproduction and Parental/Systemic
fertility effects NOAEL = 500 mg/kg/
rat (2- day in males and
generation) females
LOAEL = 1,500 mg/
kg/day in males
and females based
on soft stools,
decreased body
weight gain and
food consumption.
Focal dilation of
the kidney
observed at 30 mg/
kg/day in the 3-
generation study
was not observed
at any dose level
in this study
Reproductive
NOAEL = > 30 1,500
HDT mg/kg/day in
males and females
LOAEL = > 1,500
HDT mg/kg/day in
males and
females, not
established
Offspring
NOAEL = 500 mg/kg/
day in males and
females
LOAEL = 1,500 mg/
kg/day in males
and females based
on reduced pup
weights during
the second and
third weeks of
lactation
------------------------------------------------------------------------
870.4100 Chronic toxicity - NOAEL = 500 HDT mg/
dogs kg/day in males
and females
LOAEL = > 500 mg/
kg/day in males
and females, not
established
------------------------------------------------------------------------
870.4300 Chronic/ NOAEL = 362 mg/kg/
carcinogenic city day in males
rats LOAEL = 940 mg/kg/
day in males
based on
decreased urinary
pH, increased
incidence of
cataracts and
lens
abnormalities,
and increased
absolute and
relative (to
brain) liver
weights
NOAEL = 457 mg/kg/
day in females
LOAEL = 1,183 mg/
kg/day in females
based on
decreased body
weight gain
No evidence of
carcinogenicity
------------------------------------------------------------------------
870.4300 Carcinogenicity NOAEL = 750 mg/kg/
mice day in males
LOAEL = 4,500 mg/
kg/day in males
based on
significant
decreased body
weight gain,
hepatocyte
necrosis, and
interstitial
nephritis
NOAEL = 750 mg/kg/
day in females
LOAEL = 4,500 mg/
kg/day in females
based on
significant
decreased body
weight gain,
increased
incidence of
proximal tubule
epithelial
basophilia, and
hypertrophy in
the kidney of
females
No evidence of
carcinogenicity
------------------------------------------------------------------------
870.5100 Gene mutation Negative - non-
assay in S. mutagenic when
typhimurium tested up to
strains 1,000 [mu]g/
plate, in
presence and
absence of
activation, in S.
typhimurium
strains TA98,
TA100, TA1535 and
TA1537
------------------------------------------------------------------------
870.5100 Gene mutation Negative for
assay in E. coli reverse gene
WP2hcrA and S. mutation, both
typhimurium with and without
strain S-9, up to 5,000
[mu]g/plate (or
cytotoxicity)
with E. coli
WP2hcrA and S.
typhimurium TA98,
TA100, TA1535,
TA1537, and
TA1538
------------------------------------------------------------------------
870.5300 Gene mutation Negative - non-
assay in Chinese mutagenic at the
hamster ovary HGPRT locus in
(CHO) cells/HGPRT Chinese hamster
ovary cells
tested up to
cytotoxic
concentrations or
limit of
solubility, in
presence and
absence of
activation
------------------------------------------------------------------------
870.5385 Cytogenetics - In Negative - non-
vivo bone marrow mutagenic in rat
chromosomal bone marrow
aberration assay chromosome assay
up to 1,000 mg/kg
in both sexes of
Sprague Dawley
rats
------------------------------------------------------------------------
[[Page 51306]]
870.5550 Other mechanisms - There was no
in vitro rec- evidence of
assay with B. recombination in
subtilis the rec-assay up
to 2,000 [mu]g/
disk with B.
subtilis H17
(rec+) and M45
H17 (rec+) and
M45 (rec-) (rec-)
------------------------------------------------------------------------
870.6200 Acute N/A
neurotoxicity
screening battery
in rats
------------------------------------------------------------------------
870.6200 Subchronic N/A
neurotoxicity
screening battery
in rats
------------------------------------------------------------------------
870.6300 Developmental N/A
neurotoxicity in
rats
------------------------------------------------------------------------
870.7485 Metabolism/ Absorption was 30-
pharmacokinetics - 36% in males and
rat females.
Glyphosate was
excreted
unchanged in the
feces and urine
(97.5% minimum).
The only
metabolite
present in the
excreta was AMPA.
Less than 1% of
the absorbed dose
remained in the
carcass,
primarily bone.
Repeat dosing did
not alter
metabolism,
distribution, and
excretion.
------------------------------------------------------------------------
870.7600 Dermal penetration N/A
------------------------------------------------------------------------
B. Toxicological Endpoints
The dose at which no adverse effects are observed (the NOAEL) from
the toxicology study identified as appropriate for use in risk
assessment is used to estimate the toxicological level of concern
(LOC). However, the lowest dose at which adverse effects of concern are
identified (the LOAEL) is sometimes used for risk assessment if no
NOAEL was achieved in the toxicology study selected. An uncertainty
factor (UF) is applied to reflect uncertainties inherent in the
extrapolation from laboratory animal data to humans and in the
variations in sensitivity among members of the human population as well
as other unknowns. An UF of 100 is routinely used, 10X to account for
interspecies differences and 10X for intraspecies differences.
For dietary risk assessment (other than cancer) the Agency uses the
UF to calculate an acute or chronic reference dose (aRfD or cRfD) where
the RfD is equal to the NOAEL divided by the appropriate UF (RfD
=NOAEL/UF). Where an additional safety factor is retained due to
concerns unique to the FQPA, this additional factor is applied to the
RfD by dividing the RfD by such additional factor. The acute or chronic
population adjusted dose (aPAD or cPAD) is a modification of the RfD to
accommodate this type of FQPA safety factor.
For non-dietary risk assessments (other than cancer) the UF is used
to determine the LOC. For example, when 100 is the appropriate UF (10X
to account for interspecies differences and 10X for intraspecies
differences) the LOC is100. To estimate risk, a ratio of the NOAEL to
exposures (margin of exposure (MOE) = NOAEL/exposure) is calculated and
compared to the LOC.
The linear default risk methodology (Q*) is the primary method
currently used by the Agency to quantify carcinogenic risk. The Q*
approach assumes that any amount of exposure will lead to some degree
of cancer risk. A Q* is calculated and used to estimate risk which
represents a probability of occurrence of additional cancer cases
(e.g., risk is expressed as 1 x 106 or one in a million).
Under certain specific circumstances, MOE calculations will be used for
the carcinogenic risk assessment. In this non-linear approach, a
``point of departure'' is identified below which carcinogenic effects
are not expected. The point of departure is typically a NOAEL based on
an endpoint related to cancer effects though it may be a different
value derived from the dose response curve. To estimate risk, a ratio
of the point of departure to exposure (MOE (cancer) = point of
departure/exposures) is calculated. A summary of the toxicological
endpoints for glyphosate used for human risk assessment is shown in the
following Table 3.
Table 3.--Summary of Toxicological Dose and Endpoints for glyphosate for Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
FQPA SF* and Level of
Exposure Scenario Dose Used in Risk Concern for Risk Study and Toxicological
Assessment, UF Assessment Effects
----------------------------------------------------------------------------------------------------------------
Acute dietary (females 13-50 years None None An acute dietary
old and general population) endpoint was not
selected for the
general population or
females 13-50, since
an appropriate
endpoint attributable
to a single exposure
was not used in the
toxicology data base
----------------------------------------------------------------------------------------------------------------
Chronic dietary (all populations) NOAEL = 175 mg/kg/day FQPA SF = 1 Developmental toxicity
UF = 100............... cPAD = cRfD............ study rabbit
Chronic RfD = 1.75 mg/ FQPA SF = 1.75 mg/kg/ LOAEL = 350 mg/kg/day
kg/day. day. based on diarrhea,
nasal discharge and
death in maternal
animals
----------------------------------------------------------------------------------------------------------------
[[Page 51307]]
Short-term, and intermediate term NOAEL = 175 mg/kg/day LOC for MOE = 100 Developmental toxicity
incidental oral (Residential) study - rabbit
LOAEL = 350 mg/kg/day
based on diarrhea,
nasal discharge and
death in maternal
animals
----------------------------------------------------------------------------------------------------------------
Short-term, and long-term dermal (1- None None Based on the
30 days, 1-6 months, 6 months - intermediate systemic
lifetime) NOAEL of 1,000 mg/kg/
(Occupational/Residential)........... day inthe 21-day
dermal toxicity study
in rabbits, and the
lack of concern for
developmental and
reproductive effects,
the quantification of
dermal risks is not
required
----------------------------------------------------------------------------------------------------------------
Short-term, intermediate-term and None None Based on the systemic
long-term inhalation (1-30 days, 1-6 toxicity
months, 6 month-lifetime) NOAEL of 0.36 mg/L HDT
(Occupational/Residential)........... in the 28-day
inhalation toxicity
study in rats, and the
physical
characteristics of the
technical (wetcake),
the quantification of
inhalation risks is
not required
----------------------------------------------------------------------------------------------------------------
Cancer (oral, dermal, inhalation) Cancer classification Risk assessment not No evidence of
(Group E) required carcinogenicity
----------------------------------------------------------------------------------------------------------------
*The reference to the FQPA safety factor refers to any additional safety factor retained due to concerns unique
to the FQPA.
C. Exposure Assessment
1. Dietary exposure from food and feed uses. Tolerances have been
established (40 CFR 180.364) for the residues of glyphosate, in or on a
variety of raw agricultural commodities. The current proposal to
establish tolerances for rice, bran at 30 parts per million (ppm);
rice, grain at 15 ppm; rice, hulls at 25 ppm; wheat, forage at 10 ppm;
wheat, hay at 10 ppm; and alfalfa, seed at 0.5 ppm, and to increase the
established glyphosate tolerance for cotton, gin by-products to 150
ppm, is not expected to result in an increase in the dietary burden for
cattle, poultry, and hogs. Respective dietary burdens of 210 ppm and
220 ppm were recently estimated by the Agency for dairy and beef
cattle, including a contribution from alfalfa hay as the roughage
component of the diet with a tolerance of 400 ppm. Risk assessments
were conducted by EPA to assess dietary exposures from glyphosate in
food as follows:
i. Acute exposure. Acute dietary 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 1-day or
single exposure. A review of the toxicity data base, including the
developmental toxicity studies in rats and rabbits, did not provide an
endpoint that could be used to quantitate risk to the general
population and to females 13-50 years old from a single-dose
administration of glyphosate. Therefore, no acute dietary analysis was
conducted for glyphosate.
ii. Chronic exposure. The glyphosate chronic dietary exposure
analysis was conducted using the dietary exposure evaluation model
(DEEM) software Version 7.87, which incorporates consumption data from
the United States Department of Agriculture (USDA) Continuing Survey of
Food Intake by Individuals (CSFII), 1989-1992. The 1989-1992 data are
based on the reported consumption of more than 10,000 individuals over
3 consecutive days, and therefore, represent more than 30,000 unique
person days of data. Foods as consumed (i.e., apple pie) are linked to
raw agricultural commodities and their food forms (i.e., apples-cooked/
canned or wheat-flour) by recipe translation files internal to the DEEM
software. Consumption data are averaged for the entire U.S. population
and within population subgroups for chronic exposure assessment, but
are retained as individual consumption events for acute exposure
assessment.
For chronic dietary exposure and risk assessments, an estimate of
the residue level in each food or food-form (i.e., orange or orange-
juice) on the commodity residue list is multiplied by the average daily
consumption estimate for that food/food form. The resulting residue
consumption estimate for each food/food form is summed with the residue
consumption estimates for all other food/food forms on the commodity
residue list to arrive at the total estimated exposure. Exposure
estimates are expressed in milligrams/kilogram body weight day (mg/kg
bwt/day) and as a percent of the cPAD for chronic exposure. This
procedure is performed for each population subgroup.
The Tier 1 chronic dietary exposure analysis for glyphosate is an
upper bound estimate of chronic dietary exposure. The chronic dietary
exposure analysis was performed for the general U.S. population and all
population subgroups using DEEM assuming tolerance levels residues and
100% crop treated data for the proposed commodities and all registered
uses. For chronic dietary risk, the Agency's LOC is less than 100%
cPAD. Dietary exposure estimates for representative population
subgroups are presented in Table 4. The results of the chronic analysis
indicate that the estimated chronic dietary risk as represented by the
percent cPAD is below the Agency's LOC (100% cPAD) for the U.S.
population and all population subgroups.
[[Page 51308]]
Table 4.--Summary of Results from Chronic DEEM Analysis of Glyphosate
----------------------------------------------------------------------------------------------------------------
Subgroup Exposure (mg/kg/day) %cPAD
----------------------------------------------------------------------------------------------------------------
U.S. population (total) 0.033880 1.9
----------------------------------------------------------------------------------------------------------------
All infants (< 1 year old) 0.075573 4.3
----------------------------------------------------------------------------------------------------------------
Children (1-6 years old) 0.072077 4.1
----------------------------------------------------------------------------------------------------------------
Children (7-12 years old) 0.047851 2.7
----------------------------------------------------------------------------------------------------------------
Females (13-50 years old) 0.025983 1.5
----------------------------------------------------------------------------------------------------------------
Males (13-19 years old) 0.032773 1.9
----------------------------------------------------------------------------------------------------------------
Males (20+ years old) 0.028664 1.6
----------------------------------------------------------------------------------------------------------------
Seniors (55+ years old) 0.023927 1.4
----------------------------------------------------------------------------------------------------------------
iii. Cancer. The HED Cancer Peer Review Committee classified
glyphosate as a Group E chemical, negative for carcinogenicity in
humans, based on the absence of evidence of carcinogenicity in male and
female rats as well as in male and female mice.
iv. Anticipated residue and percent crop treated (PCT) information.
The Agency used tolerance levels and 100% PCT data for the proposed
commodities and all registered uses.
2. Dietary exposure from drinking water. The Agency lacks
sufficient monitoring exposure data to complete a comprehensive dietary
exposure analysis and risk assessment for glyphosate in drinking water.
Because the Agency does not have comprehensive monitoring data,
drinking water concentration estimates are made by reliance on
simulation or modeling taking into account data on the physical
characteristics of glyphosate.
The Agency uses the Generic Estimated Environmental Concentration
(GENEEC) or the Pesticide Root Zone/Exposure Analysis Modeling System
(PRZM/EXAMS) to estimate pesticide concentrations in surface water and
Screening Concentration in Groundwater (SCI-GROW), which predicts
pesticide concentrations in ground water. In general, EPA will use
GENEEC (a Tier 1 model) before using PRZM/EXAMS (a Tier 2 model) for a
screening-level assessment for surface water. The GENEEC model is a
subset of the PRZM/EXAMS model that uses a specific high-end runoff
scenario for pesticides. GENEEC incorporates a farm pond scenario,
while PRZM/EXAMS incorporate an index reservoir environment in place of
the previous pond scenario. The PRZM/EXAMS model includes a PC area
factor as an adjustment to account for the maximum PC coverage within a
watershed or drainage basin.
None of these models include consideration of the impact processing
(mixing, dilution, or treatment) of raw water for distribution as
drinking water would likely have on the removal of pesticides from the
source water. The primary use of these models by the Agency at this
stage is to provide a coarse screen for sorting out pesticides for
which it is highly unlikely that drinking water concentrations would
ever exceed human health levels of concern.
Since the models used are considered to be screening tools in the
risk assessment process, the Agency does not use estimated
environmental concentrations (EECs) from these models to quantify
drinking water exposure and risk as a percent (%) %RfD or %PAD.
Instead, drinking water levels of comparison (DWLOCs) are calculated
and used as a point of comparison against the model estimates of a
pesticide's concentration in water. DWLOCs are theoretical upper limits
on a pesticide's concentration in drinking water in light of total
aggregate exposure to a pesticide in food and from residential uses.
Since DWLOCs address total aggregate exposure to glyphosate, they are
further discussed in section E below.
Based on the GENEEC and SCI-GROW models, the EECs of glyphosate for
acute exposures are estimated to be 21 parts per billion (ppb) for
surface water and 0.0038 ppb for ground water. The EECs for chronic
exposures are estimated to be 0.83 ppb for surface water and 0.0038 ppb
for ground water, based on glyphosate treatment crops. To estimate the
possible concentration of glyphosate in surface water resulting from
direct application to water, the Agency assumed application to a water
body 6 feet deep. At an application rate of 3.75 lb acid equivalent
(ae)/A, the estimated concentration is 230 ppb. Because the glyphosate
water-application estimate is greater than the crop application
estimate, 230 ppb is the appropriate value to use in the chronic risk
estimate.
3. From non-dietary exposure. The term ``residential exposure'' is
used in this document to refer to non-occupational, non-dietary
exposure (e.g., for lawn and garden pest control, indoor pest control,
termiticides, and flea and tick control on pets).
i. Non-occupational (recreational) exposures. Glyphosate is
currently registered for use on the following residential non-dietary
sites: Recreational areas, including parks and golf courses for control
of broadleaf weeds and grasses, and lakes and ponds, including
reservoirs for control of nuisance aquatic weeds. Based on the
registered uses, adult and child golfers are anticipated to have short-
term post-application dermal exposure at golf courses. Swimmers
(adults, children and toddlers) are anticipated to have short-term
post-application dermal and incidental ingestion exposures. However,
since the Agency did not select dermal endpoints, no post-application
dermal assessment is included; only a post-application incidental
ingestion exposure assessment (swimmers) is included. Risk estimates
for incidental ingestion by swimmers (adults, children, and toddlers)
ranged from 7,600 to 36,000. It should be noted however, that
glyphosate is used for non-selective weed control on emerged aquatic
weeds. In this use pattern, it is unlikely that swimmers would be
present in waterbodies with floating weeds present. Thus, the inclusion
of the swimmer incidental ingestion exposure assessment is considered
by the Agency to be conservative. Table 5 presents a summary of
assumptions used to
[[Page 51309]]
estimate the exposure to adult and toddler child swimmers and the
corresponding risk estimates.
Table 5.--Assumptions and Risk Estimates for Post-Application Swimmer Exposure Assessments for Glyphosate, Isopropylamine salt
--------------------------------------------------------------------------------------------------------------------------------------------------------
Potential Dose Rate
Exposure Scenario AR1 (lb a.e./A) Maximum Concentration (PDR; oral mg/kg bw/ Short-term MOE4
in water (mg/L)2 day)3
--------------------------------------------------------------------------------------------------------------------------------------------------------
Incidental oral ingestion, adult-female 3.75 1.38 0.00493 36,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
Incidental oral, toddler 0.023 7,600
--------------------------------------------------------------------------------------------------------------------------------------------------------
1Application rate from registered labels for aquatic weed control using glyphosate IPA salt (ex. label = EPA Reg. No. 524-343; max rate = 7.5 pints/A
containing 4 lb ae glyphosate/gal. x 1 gal./4 pints = 3.75 lb ae/A.
2Maximum concentration in water (top 1 ft.) = 3.75 lb ae/A x 1A/43,560 ft2 x 454,000 mg/lb x 1/ft x ft3 /28.32 L = 1.38 mg/L.
3PDR, incidental oral exposure = concentration, Cw (mg/L) x ingestion rate, IgR (L/hr) x exposure time, ET (hrs/d) x 1/BW (adult-female = 60 kg; toddler
= 15 kg).
4MOE = NOAEL/PDR; short-term incidental oral NOAEL = 175 mg/kg bw/d; The LOC for adult females and toddlers for short-term, incidental oral exposures is
MOEs < 100.
The MOEs presented in Table 5 for post-application exposure by
swimmers to glyphosate in aquatic weed control applications are greater
than 100 and do not exceed the Agency's LOC for short-term non-
occupational (recreational) exposures (MOEs less than 100).
ii. Residential exposures. Glyphosate is also registered for
broadcast and spot treatments on home lawns and gardens by homeowners
and by lawn care operators (LCOs). Based on the registered residential
use patterns, there is a potential for short-term dermal and inhalation
exposures to homeowners who apply products containing glyphosate
(residential handlers). Additionally, based on the results of
environmental fate studies, there is also a potential for short- and
intermediate-term post-application dermal exposures by adults and
toddlers and incidental ingestion exposures by toddlers. However, since
the Agency did not select short-term or intermediate-term dermal or
inhalation endpoints, no residential handler or post-application dermal
assessment is included; only a post-application toddler assessment for
incidental ingestion exposures is included. Risk estimates for toddler
post-application incidental ingestion exposures ranged from 7,200 to
greater than 106. All recreational and residential exposures
assessed do not exceed the Agency's level of concern (MOEs less than
100). Table 6 provides a summary of the short-term and intermediate-
term risk estimates for post-application incidental ingestion exposures
to toddlers.
Table 6.--Summary of Toddler Incidental Ingestion Exposures and Risk Estimates for Residential Use of Glyphosate, Isopropylamine salt1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Activity AR (lbs a.e./A)2 Residue Estimate3 PDR (mg/kg bw/d)4 Short-term/Intermediate-term MOE5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hand-to-mouth 1.62 DFR: 0.908 [mu]g/cm2 0.0242 7,200
--------------------------------------------------------------------------------------------------------------------------------------------------------
Object-to-mouth DFR: 3.63 [mu]g/cm2 0.00605 29,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
Soil ingestion Soil residue: 12.2 8.13 x 10-5 10-6
[mu]g/g soil
--------------------------------------------------------------------------------------------------------------------------------------------------------
1Sources: Standard Operating Procedures for Residential Exposure Assessments, Draft, December 17, 1997 and Exposure SAC Policy No. 11, February 22,
2001: Recommended Revisions to the SOPs for Residential Exposure.
2AR = maximum application rate on Roundup ProDry label (EPA Reg. No. 524-505) for residential lawn treatment.
3Residue estimates based on the following protocol from the Residential SOPs:
Hand-to-mouth DFR = 1.62 lb ae/A x 0.05 x (4.54 x 10-8 [mu]g/lb ae) x (2.47 x 10-8 A/cm2) = 0.908 g/cm2.
Object-to-mouth DFR = 1.62 lb ae/A x 0.20 x (4.54 x 108 [mu]g/lb ae) x (2.47 x 10-8 A/cm2 = 3.63 [mu]g/cm2.
Soil Residue = 1.62 lb ae/A x fraction of residue in soil (100%)/cm x (4.54 x 108 [mu]g/lb ae) x (2.47 x 10-8 A/cm2) x 0.67 cm3/g = 12.2 [mu]g/g soil.
4Potential Dose Rate (PDR; already normalized to body weight of toddler).
Hand-to-mouth PDR = (0.908 g/cm2 x 0.50 x 20 cm2/event x 20 events/hr x 10-3 mg/[mu]g x 2 hrs/d)/15 kg = 0.0242 mg/kg bwt/day.
Object-to-mouth PDR = (3.63 g/cm2 x 25 cm2 /d x 10-3 mg/[mu]g)/15 kg = 0.00605 mg/kg bwt/day.
Soil Ingestion PDR = (12.2 [mu]g/g soil x 100 mg soil/d x 10-6 g/[mu]g)/15 kg = 8.13 x 10-5 mg/kg bwt/day.
5MOE = NOAEL/PDR, where the short-term incidental oral NOAEL = 175 mg/kg/day the Agency's LOC is for MOEs < 100 (short-term residential).
All MOEs calculated for post-application toddler exposures do not
exceed the Agency's level of concern for residential exposures (MOEs
less than 100).
4. Cumulative exposure to substances with a common mechanism of
toxicity. 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 does not have, at this time, available data to determine
whether glyphosate 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,
glyphosate does not appear to produce a toxic metabolite produced by
other substances. For the purposes of this
[[Page 51310]]
tolerance action, therefore, EPA has not assumed that glyphosate has a
common mechanism of toxicity with other substances. For information
regarding EPA's efforts to determine which chemicals have a common
mechanism of toxicity and to evaluate the cumulative effects of such
chemicals, see the final rule for Bifenthrin Pesticide Tolerances (62
FR 62961, November 26, 1997).
D. Safety Factor for Infants and Children
1. In general. FFDCA section 408 provides that EPA shall apply an
additional tenfold margin of safety for infants and children in the
case of threshold effects to account for prenatal and postnatal
toxicity and the completeness of the data base on toxicity and exposure
unless EPA determines that a different margin of safety will be safe
for infants and children. Margins of safety are incorporated into EPA
risk assessments either directly through use of a MOE analysis or
through using UFs (safety) in calculating a dose level that poses no
appreciable risk to humans.
2. Prenatal and postnatal sensitivity. The toxicology data base for
glyphosate is adequate according to the Subdivision F Guideline
requirements for a food-use chemical. Acceptable developmental toxicity
studies in the rat and rabbit are available, as is an acceptable 2-
generation reproduction study in the rat. Based on the available data,
the Agency determined that there is no evidence of either a
quantitative or qualitative increased susceptibility following in utero
glyphosate exposure to rats and rabbits, or following prenatal/
postnatal exposure in the 2-generation reproduction study in rats.
3. Conclusion. There is a complete toxicity data base for
glyphosate and exposure data are complete or are estimated based on
data that reasonably accounts for potential exposures. The Agency
determined that the FQPA safety factor to protect infants and children
can be removed (reduced from 10X to 1X) for all population subgroups
and exposure scenarios because:
1. The toxicology data base is complete.
2. A developmental neurotoxicity study is not required.
3. The dietary (food and drinking water) exposure assessments will
not underestimate the potential exposures for infants and children.
E. Aggregate Risks and Determination of Safety
To estimate total aggregate exposure to a pesticide from food,
drinking water, and residential uses, the Agency calculates DWLOCs
which are used as a point of comparison against the model estimates of
a pesticide's concentration in water (EECs). DWLOC values are not
regulatory standards for drinking water. DWLOCs are theoretical upper
limits on a pesticide's concentration in drinking water in light of
total aggregate exposure to a pesticide in food and residential uses.
In calculating a DWLOC, the Agency determines how much of the
acceptable exposure (i.e., the PAD) is available for exposure through
drinking water (e.g., allowable chronic water exposure (mg/kg/day) =
cPAD - (average food + residential exposure). This allowable exposure
through drinking water is used to calculate a DWLOC.
A DWLOC will vary depending on the toxic endpoint, drinking water
consumption, and body weights. Default body weights and consumption
values as used by EPA Office of Water are used to calculate DWLOCs: 2L/
70 kg (adult male), 2L/60 kg (adult female), and 1L/10 kg (child).
Default body weights and drinking water consumption values vary on an
individual basis. This variation will be taken into account in more
refined screening-level and quantitative drinking water exposure
assessments. Different populations will have different DWLOCs.
Generally, a DWLOC is calculated for each type of risk assessment used:
Acute, short-term, intermediate-term, chronic, and cancer.
When EECs for surface water and ground water are less than the
calculated DWLOCs, EPA concludes with reasonable certainty that
exposures to the pesticide in drinking water (when considered along
with other sources of exposure for which EPA has reliable data) would
not result in unacceptable levels of aggregate human health risk at
this time. Because EPA considers the aggregate risk resulting from
multiple exposure pathways associated with a pesticide's uses, levels
of comparison in drinking water may vary as those uses change. If new
uses are added in the future, EPA will reassess the potential impacts
of residues of the pesticide in drinking water as a part of the
aggregate risk assessment process.
1. Acute aggregate risk (food + drinking water). The Agency did not
identify an appropriate acute dietary endpoint that is the result of a
single-dose administration of glyphosate. Accordingly, glyphosate is
not expected to pose an acute risk.
2. Chronic aggregate risk (food + drinking water). Using the
exposure assumptions described in this unit for chronic exposure
(tolerance level residues and 100% crop treated data for all proposed
commodities and registered uses), EPA has concluded that exposure to
glyphosate from food will utilize 1.9% of the cPAD for the U.S.
population, 4.3% of the cPAD for all infants (less than 1-year old) and
4.1% of the cPAD for children 1-6 years old. The results of the chronic
analysis (Table 4 in this unit) indicate that the chronic dietary risk
estimates for the general U.S. population and all population subgroups
associated with the existing and proposed uses of glyphosate do not
exceed the Agency's LOC (less than 100% of the cPAD). Based on the use
pattern, chronic residential exposure to residues of glyphosate is not
expected. In addition, there is potential for chronic dietary exposure
to glyphosate in drinking water. After calculating DWLOCs and comparing
them to the EECs for surface water and ground water, EPA does not
expect the aggregate exposure to exceed 100% of the cPAD, as shown in
Table 7 below:
Table 7.--Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to glyphosate
----------------------------------------------------------------------------------------------------------------
Maximum
Chronic Chronic Ground Surface
Scenario/Population Subgroup cPAD,mg/kg/ Food Ex- Water Water EEC, Water EEC, Chronic
day posure mg/ Exposure1, ppb ppb DWLOC2, ppb
kg/day mg/kg/day
----------------------------------------------------------------------------------------------------------------
U.S. population 1.75 0.033880 1.716120 0.0038 230 60,000
----------------------------------------------------------------------------------------------------------------
All infants (< 1-year old) 1.75 0.075573 1.674427 0.0038 230 17,000
----------------------------------------------------------------------------------------------------------------
Children (1-6 years old) 1.75 0.072077 1.677923 0.0038 230 17,000
----------------------------------------------------------------------------------------------------------------
[[Page 51311]]
Children (7-12 years old) 1.75 0.047851 1.702149 0.0038 230 17,000
----------------------------------------------------------------------------------------------------------------
Females (13-50 years old) 1.75 0.025983 1.724017 0.0038 230 52,000
----------------------------------------------------------------------------------------------------------------
Males (13-19 years old) 1.75 0.032773 1.717227 0.0038 230 60,000
----------------------------------------------------------------------------------------------------------------
Males (20+ years old) 1.75 0.028664 1.721336 0.0038 230 60,000
----------------------------------------------------------------------------------------------------------------
Seniors (55+ years old) 1.75 0.023927 1.726073 0.0038 230 60,000
----------------------------------------------------------------------------------------------------------------
1Maximum chronic water exposure (mg/kg/day) = cPAD (mg/kg/day) - chronic food exposure from DEEMTM (mg/kg/day).
2The chronic DWLOCs were calculated as follows: DWLOC ([mu]g/L) = maximum water exposure (mg/kg/day) x body
weight (kg)/consumption (L/day) x 0.001 mg/[mu]g.
3. Short-term/intermediate-term aggregate risk (food + residential
+ water). In aggregating short-term-/intermediate-term risk, HED
considered background chronic dietary exposure (food + water) and
short-term/intermediate-term incidental oral exposures (see Tables 6
and 7). Because the incidental oral ingestion exposure estimates for
toddlers from residential turf exposures (Table 7) exceeded the
incidental oral exposure estimates from post-application swimmer
exposures (Table 6), the Agency conducted this risk assessment using
exposure estimates from just the worst-case situation. No attempt was
made to combine exposures from the swimmer and residential turf
scenarios due to the low probability of both occurring.
The total short-term/intermediate-term food and residential
aggregate MOEs are 1,800-2,300. As these MOEs are greater than 100, the
short-term/intermediate-term aggregate risk does not exceed the
Agency's LOC. For surface water and ground water, the EECs of
glyphosate are less than the DWLOCs for glyphosate in drinking water as
a contribution to short-term/intermediate-term aggregate exposure.
Therefore, the Agency concludes with reasonable certainty that residues
of glyphosate in drinking water do not contribute significantly to the
short-term/intermediate-term aggregate human health risk at the present
time. Table 8 summarizes the short-term/intermediate-term aggregate
exposure to glyphosate residues.
Table 8.--Short-Term/Intermediate-Term Aggregate Risk and DWLOC Calculations for Exposure to Glyphosate Residues
Short-Term/Intermediate-Term Exposure Scenario
----------------------------------------------------------------------------------------------------------------
Aggregate
Level of Surface Ground Short-Term/
Population Aggregate MOE (food+ Concern Water EEC3 Water EEC3 Intermediate-
residential)1 (LOC) or (ppb) (ppb) Term DWLOC4,
Target MOE2 (ppb)
----------------------------------------------------------------------------------------------------------------
All Infants < 1 year old) 1,900 100 230 0.0038 17,000
----------------------------------------------------------------------------------------------------------------
Children (1-6 years old) 1,800 100 230 0.0038 17,000
----------------------------------------------------------------------------------------------------------------
Children (7-12 years old) 2,300 100 230 0.0038 17,000
----------------------------------------------------------------------------------------------------------------
1Aggregate MOE = NOAEL/(Average food exposure + Residential exposure).
2Basis for the target MOE: interspecies and intraspecies uncertainty factors totaling 100.
3The glyphosate use producing the highest level was used.
4DWLOC ([mu]g/L or ppb) = maximum water exposure (mg/kg/day) x bwt (kg) / water consumption (L) x 10-3 mg/[mu]g
(10 kg bwt assumed).
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to the general population, and to infants and children from aggregate
exposure to glyphosate residues.
F. Analytical Enforcement Methodology
Adequate enforcement methods are available for analysis of residues
of glyphosate in or on plant and livestock commodities. These methods
include Gas Liquid Chromatography (GLC) (Method I in Pesticides
Analytical Manual (PAM) II; the limit of detection is 0.05 ppm) and
High Performance Liquid Chromatography (HPLC) with fluorometric
detection. Use of the GLC method is discouraged due to the lengthiness
of the experimental procedure. The HPLC procedure has undergone
successful Agency validation and was recommended for inclusion in PAM
II. A Gas Chromatography/Mass Spectrometry (GC/MS) method for
glyphosate in crops has also been validated by EPA's Analytical
Chemistry Laboratory (ACL). Thus, adequate analytical methods are
available for residue data collection and enforcement of the proposed
tolerance changes for glyphosate.
G. International Residue Limits
Codex and Mexican maximum residue limits (MRLS) are established for
residues of glyphosate (glifosato) per se and Canadian MRLs are
established for combined residues of glyphosate and AMPA in a variety
of raw agricultural, processed, and animal commodities. Currently no
relevant Codex MRL for cotton gin by-products is established. The
proposed ``rice, grain'' tolerance of
[[Page 51312]]
15.0 ppm is based on crop field trial data obtained when using
glyphosate-tolerant rice and thus cannot be lowered to maintain
harmonization with the CODEX MRL of 0.1 ppm for residues of glyphosate
in or on this commodity. This petition proposes no additional numerical
changes that would effect agreement between United States tolerances
and Codex MRLs.
[FR Doc. 04-18770 Filed 8-17-04; 8:45 am]
BILLING CODE 6560-50-S