[Federal Register Volume 62, Number 168 (Friday, August 29, 1997)]
[Rules and Regulations]
[Pages 45748-45754]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-23094]
[[Page 45748]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 180, 185 and 186
[OPP-300542; FRL-5739-8]
RIN 2070-AB78
Paraquat; Pesticide Tolerances for Emergency Exemptions
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes time-limited tolerances for
paraquat (1,1'-dimethyl-4,4'-bipyridinium-ion) in or on dry peas and
mustard seed. This action is in response to EPA's granting of emergency
exemptions under section 18 of the Federal Insecticide, Fungicide, and
Rodenticide Act authorizing use of the pesticide on dry peas in Idaho,
Oregon and Washington, and mustard seed in Washington. This regulation
establishes maximum permissible levels for residues of paraquat in
these food commodities pursuant to section 408(l)(6) of the Federal
Food, Drug, and Cosmetic Act, as amended by the Food Quality Protection
Act of 1996. The tolerances will expire and are revoked on November 15,
1998.
DATES: This regulation is effective August 29, 1997. Objections and
requests for hearings must be received by EPA on or before October 28,
1997.
ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [OPP-300542], must be submitted to: Hearing
Clerk (1900), Environmental Protection Agency, Rm. M3708, 401 M St.,
SW., Washington, DC 20460. Fees accompanying objections and hearing
requests shall be labeled ``Tolerance Petition Fees'' and forwarded to:
EPA Headquarters Accounting Operations Branch, OPP (Tolerance Fees),
P.O. Box 360277M, Pittsburgh, PA 15251. A copy of any objections and
hearing requests filed with the Hearing Clerk identified by the docket
control number, [OPP-300542], must also be submitted to: Public
Information and Records Integrity Branch, Information Resources and
Services Division (7506C), Office of Pesticide Programs, Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460. In person,
bring a copy of objections and hearing requests to Rm. 1132, CM #2,
1921 Jefferson Davis Hwy., Arlington, VA.
A copy of objections and hearing requests filed with the Hearing
Clerk may also be submitted electronically by sending electronic mail
(e-mail) to: opp-docket@epamail.epa.gov. Copies of objections and
hearing requests must be submitted as an ASCII file avoiding the use of
special characters and any form of encryption. Copies of objections and
hearing requests will also be accepted on disks in WordPerfect 5.1 file
format or ASCII file format. All copies of objections and hearing
requests in electronic form must be identified by the docket control
number [OPP-300542]. No Confidential Business Information (CBI) should
be submitted through e-mail. Electronic copies of objections and
hearing requests on this rule may be filed online at many Federal
Depository Libraries.
FOR FURTHER INFORMATION CONTACT: By mail: Pat Cimino, Registration
Division 7505C, Office of Pesticide Programs, Environmental Protection
Agency, 401 M St., SW., Washington, DC 20460. Office location,
telephone number, and e-mail address: Crystal Mall #2, 1921 Jefferson
Davis Hwy., Arlington, VA, (703) 308-9357, e-mail:
cimino.pat@epamail.epa.gov.
SUPPLEMENTARY INFORMATION: EPA, on its own initiative, pursuant to
section 408(e) and (l)(6) of the Federal Food, Drug, and Cosmetic Act
(FFDCA), 21 U.S.C. 346a(e) and (l)(6), is establishing tolerances for
the herbicide/desiccant/defoliant paraquat, in or on dry peas at 0.3
parts per million (ppm) and mustard seed at 5.0 ppm. These tolerances
will expire and are revoked on November 15, 1998. EPA will publish a
document in the Federal Register to remove the revoked tolerances from
the Code of Federal Regulations.
I. Background and Statutory Authority
The Food Quality Protection Act of 1996 (FQPA) (Pub. L. 104-170)
was signed into law August 3, 1996. FQPA amends both the Federal Food,
Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 301 et seq., and the Federal
Insecticide, Fungicide, and Rodenticide Act (FIFRA), 7 U.S.C. 136 et
seq . The FQPA amendments went into effect immediately. Among other
things, FQPA amends FFDCA to bring all EPA pesticide tolerance-setting
activities under a new section 408 with a new safety standard and new
procedures. These activities are described below and discussed in
greater detail in the final rule establishing the time-limited
tolerance associated with the emergency exemption for use of
propiconazole on sorghum (61 FR 58135, November 13, 1996)(FRL-5572-9).
New 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. . . .''
Section 18 of FIFRA authorizes EPA to exempt any Federal or State
agency from any provision of FIFRA, if EPA determines that ``emergency
conditions exist which require such exemption.'' This provision was not
amended by FQPA. EPA has established regulations governing such
emergency exemptions in 40 CFR part 166.
Section 408(l)(6) of the FFDCA requires EPA to establish a time-
limited tolerance or exemption from the requirement for a tolerance for
pesticide chemical residues in food that will result from the use of a
pesticide under an emergency exemption granted by EPA under section 18
of FIFRA. Such tolerances can be established without providing notice
or period for public comment.
Because decisions on section 18-related tolerances must proceed
before EPA reaches closure on several policy issues relating to
interpretation and implementation of the FQPA, EPA does not intend for
its actions on such tolerance to set binding precedents for the
application of section 408 and the new safety standard to other
tolerances and exemptions.
II. Emergency Exemptions for Paraquat on Dry Peas and Mustard Seed
and FFDCA Tolerances
The Idaho Department of Agriculture requested a regional emergency
exemption for use of paraquat dichloride (Gramoxone Plus Herbicide) for
desiccation of weeds infesting green peas grown for seed and dry peas
in Idaho, Oregon and Washington in March, 1997. Unusually cold, wet
weather delayed the pea planting season resulting in late pea emergence
and higher incidence of weed infestations in fields. Continued moist,
cool weather has contributed to weeds remaining green at harvest. Weeds
plug harvesting equipment delaying harvest and the
[[Page 45749]]
delays result in downgraded or unmarketable peas due to shattered pods,
bleached and sloughed seed coats and sprouting. There are currently no
registered pesticides or alternative methods of control which can
provide desiccation of weeds and permit harvest of the crops. After
having reviewed the submission, EPA concurs that emergency conditions
exist for these states.
The Washington Department of Agriculture requested a specific
exemption for use of paraquat (Gramoxone Extra Herbicide) for
desiccation of weeds in mustard seed grown for processing (condiment).
An early season freeze coupled with continuous cool, early season
growing conditions stunted this years' mustard crop and allowed weeds,
predominantly Russian thistle, to become established in the crop.
Affected growers will be unable to harvest infested mustard fields
without the use of a desiccant harvest aid. After having reviewed the
submission, EPA concurs that emergency conditions exist for this state.
As part of its assessment of these emergency exemptions, EPA
assessed the potential risks presented by residues of paraquat in or on
dry peas and mustard seed. In doing so, EPA considered the new safety
standard in FFDCA section 408(b)(2), and EPA decided that the necessary
tolerance under FFDCA section 408(l)(6) would be consistent with the
new safety standard and with FIFRA section 18. Consistent with the need
to move quickly on the emergency exemption in order to address an
urgent non-routine situation and to ensure that the resulting food is
safe and lawful, EPA is issuing this tolerance without notice and
opportunity for public comment under section 408(e), as provided in
section 408(l)(6). Although these tolerances will expire and are
revoked on Nov 15, 1998, under FFDCA section 408(l)(5), residues of the
pesticide not in excess of the amounts specified in the tolerance
remaining in or on dry peas and mustard seed after that date will not
be unlawful, provided the pesticide is applied in a manner that was
lawful under FIFRA. EPA will take action to revoke this tolerance
earlier if any experience with, scientific data on, or other relevant
information on this pesticide indicate that the residues are not safe.
Because this tolerance is being approved under emergency conditions
EPA has not made any decisions about whether paraquat meets EPA's
registration requirements for use on dry peas and mustard seed or
whether permanent tolerances for these uses would be appropriate. Under
these circumstances, EPA does not believe that these tolerances serve
as a basis for registration of paraquat by a State for special local
needs under FIFRA section 24(c). Nor do these tolerances serve as the
basis for any State other than Idaho, Oregon, and Washington for dry
peas and Washington for mustard seed to use this pesticide on these
crops under section 18 of FIFRA without following all provisions of
section 18 as identified in 40 CFR part 166. For additional information
regarding the emergency exemption for paraquat, contact the Agency's
Registration Division at the address provided above.
III. Risk Assessment and Statutory Findings
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. First, EPA determines the
toxicity of pesticides based primarily on toxicological studies using
laboratory animals. These studies address many adverse health effects,
including (but not limited to) reproductive effects, developmental
toxicity, toxicity to the nervous system, and carcinogenicity. Second,
EPA examines exposure to the pesticide through the diet (e.g., food and
drinking water) and through exposures that occur as a result of
pesticide use in residential settings.
A. Toxicity
1. Threshold and non-threshold effects. For many animal studies, a
dose response relationship can be determined, which provides a dose
that causes adverse effects (threshold effects) and doses causing no
observed effects (the ``no-observed effect level'' or ``NOEL'').
Once a study has been evaluated and the observed effects have been
determined to be threshold effects, EPA generally divides the NOEL from
the study with the lowest NOEL by an uncertainty factor (usually 100 or
more) to determine the Reference Dose (RfD). The RfD is a level at or
below which daily aggregate exposure over a lifetime will not pose
appreciable risks to human health. An uncertainty factor (sometimes
called a ``safety factor'') of 100 is commonly used since it is assumed
that people may be up to 10 times more sensitive to pesticides than the
test animals, and that one person or subgroup of the population (such
as infants and children) could be up to 10 times more sensitive to a
pesticide than another. In addition, EPA assesses the potential risks
to infants and children based on the weight of the evidence of the
toxicology studies and determines whether an additional uncertainty
factor is warranted. Thus, an aggregate daily exposure to a pesticide
residue at or below the RfD (expressed as 100 percent or less of the
RfD) is generally considered acceptable by EPA. EPA generally uses the
RfD to evaluate the chronic risks posed by pesticide exposure. For
shorter term risks, EPA calculates a margin of exposure (MOE) by
dividing the estimated human exposure into the NOEL from the
appropriate animal study. Commonly, EPA finds MOEs lower than 100 to be
unacceptable. This 100-fold MOE is based on the same rationale as the
100-fold uncertainty factor.
Lifetime feeding studies in two species of laboratory animals are
conducted to screen pesticides for cancer effects. When evidence of
increased cancer is noted in these studies, the Agency conducts a
weight of the evidence review of all relevant toxicological data
including short-term and mutagenicity studies and structure activity
relationship. Once a pesticide has been classified as a potential human
carcinogen, different types of risk assessments (e.g., linear low dose
extrapolations or MOE calculation based on the appropriate NOEL) will
be carried out based on the nature of the carcinogenic response and the
Agency's knowledge of its mode of action.
2. Differences in toxic effect due to exposure duration. The
toxicological effects of a pesticide can vary with different exposure
durations. EPA considers the entire toxicity data base, and based on
the effects seen for different durations and routes of exposure,
determines which risk assessments should be done to assure that the
public is adequately protected from any pesticide exposure scenario.
Both short and long durations of exposure are always considered.
Typically, risk assessments include ``acute,'' ``short-term,''
``intermediate term,'' and ``chronic'' risks. These assessments are
defined by the Agency as follows.
Acute risk, by the Agency's definition, results from 1-day
consumption of food and water, and reflects toxicity which could be
expressed following a single oral exposure to the pesticide residues.
High end exposure to food and water residues are typically assumed.
Short-term risk results from exposure to the pesticide for a period
of 1-7 days, and therefore overlaps with the acute risk assessment.
Historically, this risk assessment was intended to address primarily
dermal and inhalation exposure which could result, for example, from
residential pesticide
[[Page 45750]]
applications. However, since enaction of FQPA, this assessment has been
expanded to include both dietary and non-dietary sources of exposure,
and will typically consider exposure from food, water, and residential
uses when reliable data are available. In this assessment, risks from
average food and water exposure, and high-end residential exposure, are
aggregated. High-end exposures from all three sources are not typically
added because of the very low probability of this occurring in most
cases, and because the other conservative assumptions built into the
assessment assure adequate protection of public health. However, for
cases in which high-end exposure can reasonably be expected from
multiple sources (e.g. frequent and widespread homeowner use in a
specific geographical area), multiple high-end risks will be aggregated
and presented as part of the comprehensive risk assessment/
characterization. Since the toxicological endpoint considered in this
assessment reflects exposure over a period of at least 7 days, an
additional degree of conservatism is built into the assessment; i.e.,
the risk assessment nominally covers 1-7 days exposure, and the
toxicological endpoint/NOEL is selected to be adequate for at least 7
days of exposure. (Toxicity results at lower levels when the dosing
duration is increased.)
Intermediate-term risk results from exposure for 7 days to several
months. This assessment is handled in a manner similar to the short-
term risk assessment.
Chronic risk assessment describes risk which could result from
several months to a lifetime of exposure. For this assessment, risks
are aggregated considering average exposure from all sources for
representative population subgroups including infants and children.
B. Aggregate Exposure
In examining aggregate exposure, FFDCA section 408 requires that
EPA take into account available and reliable information concerning
exposure from the pesticide residue in the food in question, residues
in other foods for which there are tolerances, residues in groundwater
or surface water that is consumed as drinking water, and other non-
occupational exposures through pesticide use in gardens, lawns, or
buildings (residential and other indoor uses). Dietary exposure to
residues of a pesticide in a food commodity are estimated by
multiplying the average daily consumption of the food forms of that
commodity by the tolerance level or the anticipated pesticide residue
level. The Theoretical Maximum Residue Contribution (TMRC) is an
estimate of the level of residues consumed daily if each food item
contained pesticide residues equal to the tolerance. In evaluating food
exposures, EPA takes into account varying consumption patterns of major
identifiable subgroups of consumers, including infants and children.
The TMRC is a ``worst case'' estimate since it is based on the
assumptions that food contains pesticide residues at the tolerance
level and that 100% of the crop is treated by pesticides that have
established tolerances. If the TMRC exceeds the RfD or poses a lifetime
cancer risk that is greater than approximately one in a million, EPA
attempts to derive a more accurate exposure estimate for the pesticide
by evaluating additional types of information (anticipated residue data
and/or percent of crop treated data) which show, generally, that
pesticide residues in most foods when they are eaten are well below
established tolerances.
Percent of crop treated estimates are derived from federal and
private market survey data. Typically, a range of estimates are
supplied and the upper end of this range is assumed for the exposure
assessment. By using this upper end estimate of percent of crop
treated, the Agency is reasonably certain that exposure is not
understated for any significant subpopulation group. Further, regional
consumption information is taken into account through EPA's computer-
based model for evaluating the exposure of significant subpopulations
including several regional groups, to pesticide residues. For this
pesticide, the most highly exposed population subgroup non-nursing
infants (less than 1 year old) was not regionally based.
IV. Aggregate Risk Assessment and Determination of Safety
Consistent with section 408(b)(2)(D), EPA has reviewed the
available scientific data and other relevant information in support of
this action, EPA has sufficient data to assess the hazards of paraquat
and to make a determination on aggregate exposure, consistent with
section 408(b)(2), for time-limited tolerances for paraquat (1,1'-
dimethyl-4,4'-bipyridinium-ion) on dry peas at 0.3 ppm and mustard seed
at 5.0 ppm. EPA's assessment of the dietary exposures and risks
associated with establishing the tolerance follows.
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 toxic effects caused by paraquat are
discussed below.
1. Acute toxicity. Based on the proposed and existing use patterns
and tolerances and available toxicological data, there are no acute
dietary exposure endpoints of concern for paraquat.
2. Short - and intermediate - term toxicity. Short- and
intermediate-term aggregate exposure takes into account chronic dietary
food and water (considered to be a background exposure level) plus
indoor and outdoor residential uses. There are no indoor residential
uses of paraquat and based on the nature of the non-food outdoor uses,
the Agency does not expect significant exposure from the registered
outdoor residential uses (spot treatment of vegetation for ornamental
crop production) of paraquat. Therefore, a short- and intermediate-term
aggregate risk assessment has not been performed.
3. Chronic toxicity. EPA has established the RfD for paraquat at
0.0045 milligrams/kilogram/day (mg/kg/day). This RfD is based on a one
year dog feeding study with a NOEL of 15 ppm (0.45 mg/kg/day) and an
uncertainty factor of 100. Chronic pneumonitis was observed at the next
dose of paraquat tested, 30 ppm (0.93 mg/kg/day, expressed as paraquat
cation).
4. Carcinogenicity. Using its Guidelines for Carcinogen Risk
Assessment published September 24, 1986 (51 FR 33992), EPA has
classified paraquat as Group ``E'' for carcinogenicity (evidence of
noncarcinogenicity for humans.
B. Exposures and Risks
1. From food and feed uses. Tolerances have been established (40
CFR 180.205) for the herbicide/desiccant/defoliant paraquat (1,1'-
dimethyl-4,4'-bipyridinium-ion) , in or on a variety of plant raw
agricultural commodities ranging from 0.05 ppm in broccoli to 30 ppm in
bean straw, and animal commodities ranging from 0.01 ppm (non-
detectable residues) in milk and eggs to 0.30 ppm for cattle kidney.
Risk assessments were conducted by EPA to assess dietary exposures and
risks from paraquat as follows:
i. Acute exposure and risk. 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
[[Page 45751]]
a one day or single exposure. Based on the proposed and existing use
patterns and tolerances and available toxicological data, there are no
acute dietary exposure endpoints of concern for paraquat.
ii. Chronic exposure and risk. For the purpose of assessing
potential chronic dietary exposure from paraquat, EPA assumed tolerance
levels for all uses and percent of crop treated refinements for some
commodities to estimate the Anticipated Residue Contribution (ARC) from
the proposed and existing food uses of paraquat. The use of percent of
crop treated data for some of the existing food uses in this analysis
results in a more refined estimate of exposure than the TMRC.
2. From drinking water. Review of terrestrial field dissipation
data by the Environmental Fate and Effects Division indicates that
paraquat is persistent and very soluble in water but has a high
affinity to bind to sediment. As noted in ``Pesticides in Groundwater
Database'' (EPA 734-12-92-001, Sept. 1992), 971 wells were sampled in 5
states from 1983 to 1990. Eleven of the 971 wells exhibited positive
hits, up to 0.1 mg/L (ppm). However, the two wells that exhibited
concentrations at 0.1 mg/L were in Missouri, with a detection limit
which was also 0.1 mg/L. The next highest concentration of paraquat was
0.018 mg/L from a well in Virginia, where the detection limit of the
analytical method was 0.00001 mg/L. Based on the poor analytical
methodology used, the Agency believes that the Missouri data are
unreliable. There is no established Maximum Concentration Level for
residues of paraquat in drinking water. The following health advisory
levels for paraquat in drinking water have been established: children
(short-term exposure) 0.1 mg/L; children (longer-term exposure) 0.05
mg/L; adult (intermediate-term exposure) 0.2 mg/L; and adult (lifetime
exposure) 0.03 mg/L.
Because the Agency lacks sufficient water-related exposure data to
complete a comprehensive drinking water risk assessment for many
pesticides, EPA has commenced and nearly completed a process to
identify a reasonable yet conservative bounding figure for the
potential contribution of water-related exposure to the aggregate risk
posed by a pesticide. In developing the bounding figure, EPA estimated
residue levels in water for a number of specific pesticides using
various data sources. The Agency then applied the estimated residue
levels, in conjunction with appropriate toxicological endpoints (RfD's
or acute dietary NOEL's) and assumptions about body weight and
consumption, to calculate, for each pesticide, the increment of
aggregate risk contributed by consumption of contaminated water. While
EPA has not yet pinpointed the appropriate bounding figure for exposure
from contaminated water, the ranges the Agency is continuing to examine
are all below the level that would cause paraquat to exceed the RfD if
the tolerance being considered in this document were granted. The
Agency has therefore concluded that the potential exposures associated
with paraquat in water, even at the higher levels the Agency is
considering as a conservative upper bound, would not prevent the Agency
from determining that there is a reasonable certainty of no harm if the
tolerance is granted.
3. From non-dietary exposure. Paraquat is registered for use in
federal conservation reserve programs and for weed control in
ornamental crop production; however, the Agency does not expect
significant exposure from these registered outdoor non-food uses.
4. Cumulative exposure to substances with 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.'' The Agency believes that ``available
information'' in this context might include not only toxicity,
chemistry, and exposure data, but also scientific policies and
methodologies for understanding common mechanisms of toxicity and
conducting cumulative risk assessments. For most pesticides, although
the Agency has some information in its files that may turn out to be
helpful in eventually determining whether a pesticide shares a common
mechanism of toxicity with any other substances, EPA does not at this
time have the methodologies to resolve the complex scientific issues
concerning common mechanism of toxicity in a meaningful way. EPA has
begun a pilot process to study this issue further through the
examination of particular classes of pesticides. The Agency hopes that
the results of this pilot process will increase the Agency's scientific
understanding of this question such that EPA will be able to develop
and apply scientific principles for better determining which chemicals
have a common mechanism of toxicity and evaluating the cumulative
effects of such chemicals. The Agency anticipates, however, that even
as its understanding of the science of common mechanisms increases,
decisions on specific classes of chemicals will be heavily dependent on
chemical specific data, much of which may not be presently available.
Although at present the Agency does not know how to apply the
information in its files concerning common mechanism issues to most
risk assessments, there are pesticides as to which the common mechanism
issues can be resolved. These pesticides include pesticides that are
toxicologically dissimilar to existing chemical substances (in which
case the Agency can conclude that it is unlikely that a pesticide
shares a common mechanism of activity with other substances) and
pesticides that produce a common toxic metabolite (in which case common
mechanism of activity will be assumed).
EPA does not have, at this time, available data to determine
whether paraquat 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,
paraquat does not appear to produce a toxic metabolite produced by
other substances. For the purposes of this tolerance action, therefore,
EPA has not assumed that paraquat has a common mechanism of toxicity
with other substances.
C. Aggregate Risks and Determination of Safety for U.S. Population
1. Acute risk. No acute toxicity effect of concern was identified
by the Agency, so this risk assessment is not required.
2. Chronic risk. Using the ARC exposure assumptions described
above, EPA has concluded that aggregate exposure to paraquat from
dietary (food only) sources will utilize 10 % of the RfD for the U.S.
population. The major identifiable subgroup with the highest aggregate
exposure is non-nursing infants less than 1 year old. The chronic risk
for infants and children is discussed below. EPA generally has no
concern for exposures below 100% of the RfD because the RfD represents
the level at or below which daily aggregate dietary exposure over a
lifetime will not pose appreciable risks to human health. Despite the
potential for exposure to paraquat in drinking water and from non-
dietary, non-occupational exposure, EPA does not expect the aggregate
exposure to exceed 100% of the RfD. EPA concludes that there is a
reasonable certainty that no harm will result from aggregate exposure
to paraquat residues.
[[Page 45752]]
3. Short- and intermediate-term risk. Short- and intermediate-term
aggregate exposure takes into account chronic dietary food and water
(considered to be a background exposure level) plus indoor and outdoor
residential exposure. There are no indoor residential uses for paraquat
and based on the nature of the outdoor non-food uses, the Agency does
not expect significant exposure from the registered outdoor residential
uses (spot treatment of vegetation for ornamental crop production) of
paraquat. Therefore, a short- and intermediate-term aggregate risk
assessment has not been performed.
E. Aggregate Risks and Determination of Safety for Infants and Children
1. Safety factor for infants and children. i. In general. In
assessing the potential for additional sensitivity of infants and
children to residues of paraquat, EPA considered data from
developmental toxicity studies in the rat and mouse and a two-
generation reproduction study in the rat. The developmental toxicity
studies are designed to evaluate adverse effects on the developing
organism resulting from pesticide exposure during prenatal development
to one or both parents. Reproduction studies provide information
relating to effects from exposure to the pesticide on the reproductive
capability of mating animals and data on systemic toxicity.
FFDCA section 408 provides that EPA shall apply an additional
tenfold margin of safety for infants and children in the case of
threshold effects to account for pre-and post-natal toxicity and the
completeness of the database 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 uncertainty (safety)
factors in calculating a dose level that poses no appreciable risk to
humans. EPA believes that reliable data support using the standard MOE
and uncertainty factor (usually 100 for combined inter- and intra-
species variability)) and not the additional tenfold MOE/uncertainty
factor when EPA has a complete data base under existing guidelines and
when the severity of the effect in infants or children or the potency
or unusual toxic properties of a compound do not raise concerns
regarding the adequacy of the standard MOE/safety factor.
ii. Developmental toxicity studies-- a. Rats. The maternal NOEL was
1 mg/kg/day. The maternal LOEL of 5 mg/kg/day (expressed as paraquat
cation) was based on clinical signs of thin and hunched appearance, and
decreased body weight gains. Developmental toxicity was manifested as
decreases in fetal body weight and delayed ossification in forelimb and
hindlimb digits; the NOEL and LOEL were 1 mg/kg/day and 5 mg/kg/day,
respectively.
b. Mice. The maternal NOEL was 1 mg/kg/day expressed as paraquat
cation). The maternal LOEL of 5 mg/kg/day was based on a reduction in
body weight gain. The NOEL for developmental toxicity was also 1 mg/kg/
day. The LOEL of 5 mg/kg/day was based on partially ossified 4th
sternebrae.
iii. Reproductive toxicity study--Rats. The NOEL for systemic
toxicity in the adults was 25 ppm (1.25 mg/kg/day). The LOEL of 75 ppm
(3.75 mg/kg/day), expressed as paraquat cation, was based on the
increased incidence of alveolar histiocytosis in the parents. The
reproductive/developmental toxicity NOEL was considered to be > 150 ppm
(7.5 mg/kg/day, expressed as paraquat cation) at the highest dose
tested since no reproductive effects were presented in this study.
iv. Pre- and post-natal sensitivity. The pre- and post-natal
toxicology data base for paraquat is complete with respect to current
toxicological data requirements.
In the rat developmental study, the maternal (systemic) NOEL and
the developmental NOEL are both 1 mg/kg/day. The LOELs are 5 mg/kg/day
for both maternal and developmental effects. The developmental results
at 5 mg/kg/day do not indicate any severe effects compared to the
maternal effects at the LOEL. In the mouse developmental study, the
maternal (systemic) and developmental NOELs were established at 1 mg/
kg/day with the LOELs set at 5 mg/kg/day. The developmental effects at
the LOEL of 5 mg/kg/day do not demonstrate any special pre-natal
sensitivity for infants and children which would require an additional
safety factor.
In both studies, maternal and developmental NOEL/LOEL levels and
effects at the LOEL suggest that there is no increased sensitivity for
infants and children from exposure to paraquat residues in the diet.
In the rat reproduction study the parental (systemic) NOEL was 1.25
mg/kg/day. The pup NOEL was considered to be > 7.5 mg/kg/day at the
highest dose tested which suggests that there is no increased post-
natal sensitivity to paraquat.
v. Conclusion. The effects observed in the mouse and rat
developmental studies and the rat reproductive study did not
demonstrate any special pre- or post-natal sensitivity for infants and
children.
The Agency concludes that reliable data support use of the standard
100-fold uncertainty factor and that an additional uncertainty factor
is not needed to protect infants and children.
2. Acute risk. No acute effect endpoint of concern was identified
by the Agency so this risk assessment is not required.
3. Chronic risk. Using the conservative exposure assumptions
described above, EPA has concluded that the percentage of the RfD that
will be utilized from dietary (food only) exposure to paraquat ranges
from 12% for nursing infants to 31% for non-nursing infants less than 1
year old. EPA generally has no concern for exposures below 100% of the
RfD because the RfD represents the level at or below which daily
aggregate dietary exposure over a lifetime will not pose appreciable
risks to human health. Under current guidelines, the registered
residential uses (weed control in ornamental crop production) do not
fall under a chronic scenario. Despite the potential for exposure to
paraquat in drinking water and from non-dietary, non-occupational
exposure, EPA does not expect the aggregate exposure to exceed 100% of
the RfD. EPA concludes that there is a reasonable certainty that no
harm will result to infants and children from aggregate exposure to
paraquat residues.
V. Other Considerations
A. Metabolism In Plants and Animals
The qualitative nature of the residue in plants and animals has
been determined. The residue of concern is the parent compound,
paraquat, only, as specified in 40 CFR 180.205.
B. Analytical Enforcement Methodology
Method I of PAM, Vol. II (spectrophotometric), is adequate for
tolerance enforcement purposes. In addition, the Agency concluded that
Method 1B adequately recovers paraquat cation residues from samples of
potatoes and soybeans treated with radiolabeled paraquat.
C. Magnitude of Residues
Residues of paraquat are not expected to exceed 0.3 ppm in/on dry
peas and 5.0 ppm in/on mustard seed as a result of these section 18
uses. For the purposes of the dried pea section 18 requests only, the
Agency is willing to accept the proposed prohibition for feeding the
pea byproducts. No animal feed items are associated with the proposed
use on mustard seed.
[[Page 45753]]
D. International Residue Limits
No CODEX, Canadian, and/or Mexican MRLs/tolerances have been
established for residues of paraquat on peas or mustard seed.
E. Rotational Crop Restrictions.
As noted in the residue chemistry chapter of the Paraquat
Reregistration Eligibility Document, no plantback restrictions or field
rotational crop studies are required.
VI. Conclusion
Therefore, tolerances are established for paraquat (1,1'-dimethyl-
4,4'-bipyridinium-ion) in/on dry peas at 0.3 ppm and mustard seed at
5.0 ppm in 40 CFR 180.205. In addition, Sec. 180.205 was restructured
in a final rule published in the Federal Register on May 2, 1997 (62 FR
24045)(FRL-5713-2) to combine the tolerances for food and feed
commodities and raw agricultural commidities into the same section. At
that time the food and feed additive tolerances in Secs. 185.4700 and
186.4700 were combined with the tolerances in Sec. 180.205(a).
Therefore, Secs. 185.4700 and 186.4700 are no longer necessary and are
removed in this rule.
VII. Objections and Hearing Requests
The new FFDCA section 408(g) provides essentially the same process
for persons to ``object'' to a tolerance regulation issued by EPA under
new section 408(e) and (l)(6) as was provided in the old section 408
and in section 409. However, the period for filing objections is 60
days, rather than 30 days. EPA currently has procedural regulations
which govern the submission of objections and hearing requests. These
regulations will require some modification to reflect the new law.
However, until those modifications can be made, EPA will continue to
use those procedural regulations with appropriate adjustments to
reflect the new law.
Any person may, by October 28, 1997, file written objections to any
aspect of this regulation and may also request a hearing on those
objections. Objections and hearing requests must be filed with the
Hearing Clerk, at the address given above (40 CFR 178.20). A copy of
the objections and/or hearing requests filed with the Hearing Clerk
should be submitted to the OPP docket for this rulemaking. The
objections submitted must specify the provisions of the regulation
deemed objectionable and the grounds for the objections (40 CFR
178.25). Each objection must be accompanied by the fee prescribed by 40
CFR 180.33(i). If a hearing is requested, the objections must include a
statement of the factual issues on which a hearing is requested, the
requestor's contentions on such issues, and a summary of any evidence
relied upon by the requestor (40 CFR 178.27). A request for a hearing
will be granted if the Administrator determines that the material
submitted shows the following: There is genuine and substantial issue
of fact; there is a reasonable possibility that available evidence
identified by the requestor would, if established, resolve one or more
of such issues in favor of the requestor, taking into account
uncontested claims or facts to the contrary; and resolution of the
factual issues in the manner sought by the requestor would be adequate
to justify the action requested (40 CFR 178.32). Information submitted
in connection with an objection or hearing request may be claimed
confidential by marking any part or all of that information as
Confidential Business Information (CBI). Information so marked will not
be disclosed except in accordance with procedures set forth in 40 CFR
part 2. A copy of the information that does not contain CBI must be
submitted for inclusion in the public record. Information not marked
confidential may be disclosed publicly by EPA without prior notice.
VIII. Public Docket
EPA has established a record for this rulemaking under docket
control number [OPP-300542] (including any comments and data submitted
electronically). A public version of this record, including printed,
paper versions of electronic comments, which does not include any
information claimed as CBI, is available for inspection from 8:30 a.m.
to 4 p.m., Monday through Friday, excluding legal holidays. The public
record is located in Room 1132 of the Public Information and Records
Integrity Branch, Information Resources and Services Division (7506C),
Office of Pesticide Programs, Environmental Protection Agency, Crystal
Mall #2, 1921 Jefferson Davis Highway, Arlington, VA.
Electronic comments may be sent directly to EPA at:
opp-docket@epamail.epa.gov.
Electronic comments must be submitted as an ASCII file avoiding the
use of special characters and any form of encryption.
The official record for this rulemaking, as well as the public
version, as described above will be kept in paper form. Accordingly,
EPA will transfer any copies of objections and hearing requests
received electronically into printed, paper form as they are received
and will place the paper copies in the official rulemaking record which
will also include all comments submitted directly in writing. The
official rulemaking record is the paper record maintained at the
Virginia address in ``ADDRESSES'' at the beginning of this document.
IX. Regulatory Assessment Requirements
This final rule establishes a time limited tolerance on EPA's own
initiative, under FFDCA section 408(d). The Office of Management and
Budget (OMB) has exempted these types of actions from review under
Executive Order 12866, entitled Regulatory Planning and Review (58 FR
51735, October 4, 1993). This final rule does not contain any
information collections subject to OMB approval under the Paperwork
Reduction Act (PRA), 44 U.S.C. 3501 et seq., or impose any enforceable
duty or contain any unfunded mandate as described under Title II of the
Unfunded Mandates Reform Act of 1995 (UMRA) (Pub. L. 104-4). Nor does
it require any prior consultation as specified by Executive Order
12875, entitled Enhancing the Intergovernmental Partnership (58 FR
58093, October 28, 1993), or special considerations as required by
Executive Order 12898, entitled Federal Actions to Address
Environmental Justice in Minority Populations and Low-Income
Populations (59 FR 7629, February 16, 1994), or require OMB review in
accordance with Executive Order 13045, entitled Protection of Children
from Environmental Health Risks and Safety Risks (62 FR 19885, April
23, 1997).
In addition, since these tolerances and exemptions that are
established on the basis of a petition under FFDCA section 408(d), such
as the time limited tolerance in this final rule, do not require the
issuance of a proposed rule, the requirements of the Regulatory
Flexibility Act (RFA) (5 U.S.C. 601 et seq.) do not apply.
Nevertheless, the Agency has previously assessed whether establishing
tolerances, exemptions from tolerances, raising tolerance levels or
expanding exemptions might adversely impact small entities and
concluded, as a generic matter, that there is no adverse economic
impact. The factual basis for the Agency's generic certification for
tolerance actions published on May 4, 1981 (46 FR 24950), and was
provided to the Chief Counsel for Advocacy of the Small Business
Administration.
X. Submission to Congress and the General Accounting Office
Under 5 U.S.C. 801(a)(1)(A), as added by the Small Business
Regulatory
[[Page 45754]]
Enforcement Fairness Act of 1996, the Agency has submitted a report
containing this rule and other required information to the U.S. Senate,
the U.S. House of Representatives, and the Comptroller General of the
General Accounting Office prior to publication of this rule in today's
Federal Register. This is not a ``major rule'' as defined by 5 U.S.C.
804(2).
List of Subjects
40 CFR Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.
40 CFR Part 185
Environmental protection, Food additives, Pesticides and pests.
40 CFR Part 186
Environmental protection, Animal feeds, Pesticides and pests.
Dated: August 18, 1997.
James Jones,
Acting Director, Registration Division, Office of Pesticide Programs.
Therefore, 40 CFR chapter I, parts 180, 185, and 186 is amended as
follows:
PART 180--[AMENDED]
1. In part 180:
a. The authority citation for part 180 continues to read as
follows:
Authority : 21 U.S.C. 346a and 371.
b. In Sec. 180.205, the table in paragraph (b) is amended by
ordering alphabetically the existing entries, and by adding
alphabetically entries for ``peas, (dry),'' and ``mustard, seed,'' to
read as follows:
Sec. 180.205 Paraquat; tolerances for residues.
* * * * *
(b) * * *
------------------------------------------------------------------------
Expiration/
Commodity Parts per million Revocation Date
------------------------------------------------------------------------
* * * * *
Peas (dry)...................... 0.3 November 15, 1998
Mustard, seed................... 5.0 November 15, 1998
* * * * *
------------------------------------------------------------------------
* * * * *
PART 185--[AMENDED]
2. In part 185:
a. The authority citation for part 185 continues to read as
follows:
Authority : 21 U.S.C. 346a and 348.
Sec. 185.4700 [Removed]
b. Section 185.4700 is removed.
PART 186--[AMENDED]
3. In part 186:
a. The authority citation for part 186 continues to read as
follows:
Authority : 21 U.S.C. 346a and 348.
Sec. 186.4700 [Removed]
b. Section 186.4700 is removed.
[FR Doc. 97-23094 Filed 8-28-97; 8:45 am]
BILLING CODE 6560-50-F
