[Federal Register Volume 62, Number 100 (Friday, May 23, 1997)]
[Rules and Regulations]
[Pages 28355-28361]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-13643]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300493; FRL-5718-5]
RIN 2070-AB78
Pendimethalin; Pesticide Tolerance for Emergency Exemption
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes time-limited tolerances for
residues of the herbicide pendimethalin and its 3,5-dinitrobenzyl
alcohol metabolite (CL 202, 347) in or on fresh mint hay and mint oil
in connection with EPA's granting an emergency exemption under section
18 of the Federal Insecticide, Fungicide, and Rodenticide Act
authorizing use of the pesticide on mint in Idaho, Oregon, South Dakota
and Washington. These tolerances will expire and are revoked on May 31,
1998.
DATES: This regulation becomes effective May 23, 1997. Objections and
requests for hearings must be received by EPA on or before July 22,
1997.
ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [OPP-300493], 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-300493], must be submitted to: Public Information
and Records Integrity Branch, Information Resources and Services
Division, (7506C), Office of Pesticide Programs, Environmental
[[Page 28356]]
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-300493]. 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: Stephen Schaible,
Registration Division (7505W), Office of Pesticide Programs,
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460.
Office location, telephone number, and e-mail address: Sixth Floor,
Crystal Station #1, 2800 Jefferson Davis Highway, Arlington, VA 22202.
(703) 308-8337, e-mail: schaible.stephen@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 combined residues of the herbicide pendimethalin and its 3,5-
dinitrobenzyl alcohol metabolite (CL 202, 347), hereafter referred to
in this document as pendimethalin, in or on fresh mint hay at 0.1 parts
per million (ppm) and in or on mint oil at 5.0 ppm. These tolerances
will expire and be revoked by EPA on May 31, 1998. After May 31, 1998,
EPA will publish a document in the Federal Register removing the
revoked tolerance 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 FFDCA, 21
U.S.C. 301 et seq., and the Federal Insecticide, Fungicide, and
Rodenticide Act (FIFRA), 7 U.S.C. 136 et seq. Among other things, FQPA
amends FFDCA to bring all EPA pesticide tolerance-setting activities
under 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 CFR 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 Exemption for Pendimethalin on Mint and FFDCA
Tolerances
On March 3, 1997, the Idaho, Oregon, and Washington State
Departments of Agriculture availed of themselves the authority to
declare the existence of a crisis situation within their states,
thereby authorizing use under FIFRA section 18 of pendimethalin on mint
to control kochia (Kochia scoparia) and redroot pigweed (Amaranthus
retroflexus). The South Dakota Department of Agriculture has since
requested a specific exemption for the same use. Kochia and redroot
pigweed have become serious pests for mint growers in these states. The
loss of mechanical control as a weed control option (due to potential
spread of Verticillium wilt by tillage equipment), lack of a
satisfactory herbicide, and the presence of herbicide-resistant pigweed
and kochia have all contributed to the development of this emergency
condition. Additionally, the presence of these weeds in the harvested
mint results in reduction in quality and price of the mint oil. Without
effective control of these weeds, yield losses of up to 35% in these
states are expected, resulting in significant economic losses to the
mint growers.
As part of its assessment of this emergency exemption, EPA assessed
the potential risks presented by residues of pendimethalin in or on
mint. In doing so, EPA considered the new safety standard in FFDCA
section 408(b)(2), and EPA decided that the necessary tolerances under
FFDCA section 408(l)(6) would be consistent with the new safety
standard and with FIFRA section 18. These tolerances will permit the
marketing of mint treated in accordance with the provisions of the
section 18 emergency exemption. 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 these tolerances 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 May
31, 1998, under FFDCA section 408(l)(5), residues of the pesticide not
in excess of the amounts specified in the tolerances remaining in or on
mint hay and mint oil after that date will not be unlawful, provided
the pesticide is applied during the term of, and in accordance with all
the conditions of, section 18 of FIFRA. EPA will take action to revoke
these tolerances earlier if any experience with, scientific data on, or
other relevant information on this pesticide indicate that the residues
are not safe.
EPA has not made any decisions about whether pendimethalin meets
EPA's registration requirements for use on mint or whether permanent
tolerances for this use would be appropriate. These tolerances do not
serve as a basis for registration of
[[Page 28357]]
pendimethalin by a State for special local needs under FIFRA section
24(c). Nor do these tolerances serve as the basis for any States other
than Idaho, Oregon, South Dakota or Washington to use this pesticide on
this crop 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 pendimethalin, 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. For many
of these 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% 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
hundredfold margin of exposure is based on the same rationale as the
hundredfold 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 margin of exposure 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.
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. 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 <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.="" pendimethalin="" is="" already="" registered="" by="" epa="" for="" numerous="" food="" and="" feed="" uses,="" as="" well="" as="" residential="" use="" on="" ornamental="" lawns,="" grasses,="" ground="" covers,="" turf,="" and="" ornamental="" plantings.="" for="" the="" purpose="" of="" this="" emergency="" exemption,="" epa="" has="" sufficient="" data="" to="" assess="" the="" hazards="" of="" pendimethalin="" and="" to="" make="" a="" determination="" on="" aggregate="" exposure,="" consistent="" with="" 408(b)(2),="" for="" time-limited="" tolerances="" for="" residues="" of="" pendimethalin="" on="" fresh="" mint="" (peppermint,="" spearmint)="" hay="" at="" 0.1="" ppm="" and="" mint="" (peppermint,="" spearmint)="" oil="" at="" 5.0="" ppm.="" epa's="" assessment="" of="" the="" dietary="" exposures="" and="" risks="" associated="" with="" establishing="" these="" tolerances="" 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="" pendimethalin="" are="" discussed="" below.="" 1.="" acute="" toxicity.="" for="" acute="" dietary="" risk="" assessment,="" the="" agency="" has="" determined="" that="" there="" are="" no="" toxicological="" endpoints="" of="" concern="" and="" that="" this="" risk="" assessment="" is="" not="" required.="" 2.="" short-="" and="" intermediate-term="" toxicity.="" opp="" has="" determined="" that="" short-="" and="" intermediate-term="" risk="" assessments="" are="" appropriate="" for="" non-="" occupational,="" non-dietary="" routes="" of="" exposure.="" opp="" recommends="" that="" the="" noel="" of="" 10="" milligrams="" per="" kilogram="" per="" day="" (mg/kg/day),="" taken="" from="" the="" 56-day="" thyroid="" function="" study="" in="" rats,="" be="" used="" for="" the="" [[page="" 28358]]="" short="" and="" intermediate="" term="" moe="" calculations.="" the="" lowest="" effect="" level="" (lel)="" of="" 31="" mg/kg/day="" from="" a="" 14-day="" intrathyroid="" metabolism="" study="" in="" rats="" was="" based="" on="" thyroid="" hormonal="" effects="" occurring="" as="" early="" as="" day="" 3.="" though="" these="" endpoints="" have="" been="" identified,="" no="" acceptable="" reliable="" exposure="" data="" to="" assess="" these="" potential="" risks="" are="" available="" at="" this="" time.="" 3.="" chronic="" toxicity.="" the="" rfd="" of="" 0.1="" mg/kg/day="" was="" established="" based="" on="" a="" combination="" of="" three="" studies="" in="" male="" rats:="" (i)="" a="" 56-day="" oral="" thyroid="" function="" study;="" (ii)="" a="" 92-day="" thyroid="" function="" study;="" and="" (iii)="" a="" 14-day="" intrathyroidal="" metabolism="" study.="" the="" noel="" was="" established="" at="" 10="" mg/kg/day.="" the="" loel="" of="" 31="" mg/kg/day="" was="" based="" on="" thyroid="" hormonal="" changes="" and="" histologic="" thyroid="" changes.="" an="" uncertainty="" factor="" (uf)="" of="" 100="" was="" applied="" to="" account="" for="" both="" interspecies="" and="" intraspecies="" variability.="" 4.="" carcinogenicity.="" pendimethalin="" has="" been="" classified="" as="" a="" group="" c,="" ``possible="" human="" carcinogen'',="" chemical="" by="" opp,="" based="" on="" a="" statistically="" significant="" increased="" trend="" and="" pairwise="" comparison="" between="" the="" high="" dose="" group="" and="" controls="" for="" thyroid="" follicular="" cell="" adenomas="" in="" male="" and="" female="" rats.="" opp="" recommends="" using="" the="" rfd="" approach="" for="" quantification="" of="" human="" risk.="" therefore,="" the="" rfd="" is="" deemed="" protective="" of="" all="" chronic="" human="" health="" effects,="" including="" cancer.="" b.="" aggregate="" exposure="" tolerances="" have="" been="" established="" (40="" cfr="" 180.361)="" for="" the="" combined="" residues="" of="" pendimethalin="" and="" its="" 3,5-dinitrobenzyl="" alcohol="" metabolite="" (cl="" 202,="" 347),="" in="" or="" on="" a="" variety="" of="" raw="" agricultural="" commodities="" at="" levels="" ranging="" from="" 0.05="" ppm="" in="" rice="" grain="" to="" 0.1="" ppm="" in="" corn,="" peanuts,="" soybeans="" and="" other="" commodities.="" the="" proposed="" time-limited="" tolerances="" are="" based="" on="" residue="" data="" provided="" with="" the="" section="" 18="" submissions.="" there="" are="" no="" livestock="" feed="" items="" associated="" with="" this="" section="" 18="" use,="" so="" no="" additional="" livestock="" dietary="" burden="" is="" expected.="" for="" the="" purpose="" of="" assessing="" potential="" chronic="" dietary="" exposure="" from="" pendimethalin,="" epa="" assumed="" tolerance="" level="" residues="" and="" 100%="" crop="" treated="" to="" estimate="" the="" theoretical="" maximum="" residue="" contribution="" (tmrc)="" for="" major="" identifiable="" subgroups="" of="" consumers,="" including="" infants="" and="" children,="" from="" the="" proposed="" and="" existing="" food="" uses="" of="" pendimethalin.="" the="" use="" of="" these="" assumptions="" results="" in="" a="" conservative="" dietary="" exposure="" assessment,="" which="" epa="" takes="" into="" consideration="" when="" making="" a="" safety="" determination="" for="" the="" subject="" section="" 18="" tolerances.="" in="" examining="" aggregate="" exposure,="" fqpa="" directs="" epa="" to="" consider="" available="" information="" concerning="" exposures="" from="" the="" pesticide="" residue="" in="" food="" and="" all="" other="" non-occupational="" exposures.="" the="" primary="" non-food="" sources="" of="" exposure="" the="" agency="" looks="" at="" include="" drinking="" water="" (whether="" from="" groundwater="" or="" surface="" water),="" and="" exposure="" through="" pesticide="" use="" in="" gardens,="" lawns,="" or="" buildings="" (residential="" and="" other="" indoor="" uses).="" based="" on="" information="" in="" the="" herbicide="" handbook="" of="" the="" weed="" science="" society="" of="" america="" (7th="" ed,="" 1994),="" pendimethalin="" has="" low="" solubility="" in="" water="" and="" strong="" absorption="" to="" soil.="" pendimethalin="" is="" essentially="" immobile="" in="" all="" soil="" types,="" being="" strongly="" bound="" to="" organic="" matter="" and="" clay,="" thus="" minimizing="" its="" potential="" to="" runoff="" to="" surface="" water="" or="" leach="" to="" ground="" water.="" no="" maximum="" concentration="" level="" and="" no="" health="" advisory="" level="" has="" been="" established="" for="" residues="" of="" pendimethalin="" in="" drinking="" water.="" information="" in="" the="" pesticides="" in="" groundwater="" database="" (epa="" 734-12-92-="" 001,="" 9/92)="" indicates="" that="" 1,405="" wells="" were="" sampled="" for="" residues="" of="" pendimethalin.="" detectable="" residues="" were="" reported="" (0.02="" to="" 0.9="">/L) in only 1% (14) of those sampled wells.
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 exposure from pendimethalin 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 pendimethalin 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.
Pendimethalin is currently registered for use on the following
residential non-food sites: ornamental lawns, grasses, ground covers,
turf, and ornamental plantings. While EPA does not consider that these
types of outdoor residential uses constitute a chronic residential
exposure scenario, EPA acknowledges that there may be short- and
intermediate-term non-occupational exposure scenarios. OPP has
identified toxicity endpoints for short- and intermediate-term
residential risk assessment. However, no acceptable reliable exposure
data to assess these potential risks are available at this time. Given
the time-limited nature of this request, the need to make emergency
exemption decisions quickly, and the significant scientific uncertainty
at this time about how to aggregate non-occupational exposure with
dietary exposure, the Agency will make its safety determination for
these tolerances based on those factors which it can reasonably
integrate into a risk assessment.
C. 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
[[Page 28359]]
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 pendimethalin 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,
pendimethalin 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 pendimethalin has a common mechanism of
toxicity with other substances.
D. Aggregate Risks and Determination of Safety for U.S. Population
1. Chronic risk. Using the conservative exposure assumptions
described above, EPA has concluded that aggregate exposure to
pendimethalin from food will utilize less than 1% 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
(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 pendimethalin 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
pendimethalin residues.
2. Cancer risk. Pendimethalin has been classified as a Group C,
``possible human carcinogen'', chemical by OPP; it is recommended that
the RfD approach for quantification of human risk be used. Given that
the RfD is considered protective of all chronic human health effects,
including cancer, and that EPA does not expect aggregate exposure to
the U.S. population to exceed 100% of the RfD, carcinogenicity
resulting from aggregate exposure to pendimethalin residues is not of
concern.
E. Aggregate Risks and Determination of Safety for Infants and Children
In assessing the potential for additional sensitivity of infants
and children to residues of pendimethalin, EPA considered data from
developmental toxicity studies in the rat and rabbit and a 2-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.
The pre- and post-natal toxicology data base for pendimethalin is
complete with respect to current toxicological data requirements. The
data base does not indicate a potential for increased sensitivity from
pre- and post-natal exposure.
No developmental toxicity was observed in either the rat or rabbit
developmental toxicity studies, nor was there any evidence in the 2-
generation toxicity study that there was developmental or reproductive
toxicity at dose levels below those in which parental toxicity was
observed. For rabbits, the developmental toxicity NOEL was > 60 mg/kg/
day, at the highest dose tested (HDT). The maternal NOEL was > 60 mg/
kg/day, based upon mortality observed at 125 mg/kg/day in a pilot
study. For rats, there were no maternal or developmental effects at any
dose level and the NOELs were 500 mg/kg/day, the highest
dose tested.
In the 2-generation reproductive toxicity study in rats, the
parental (systemic) NOEL could not be determined at the doses tested.
The reproductive NOEL was 172 mg/kg/day. The reproductive LOEL of 346
mg/kg/day was based on decreased pup weight, which occurred in the
presence of parental (systemic) toxicity at 346 mg/kg/day.
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 margin of exposure 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 margin of exposure and uncertainty factor (usually
100 for combined inter- and intra-species variability)) and not the
additional tenfold margin of exposure/uncertainty factor when EPA has a
complete database 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 margin of exposure/safety factor.
The reproductive NOEL of 172 mg/kg/day is seventeenfold higher than
the NOEL of 10 mg/kg/day used for the RfD. Additionally, the
reproductive LOEL occurred in the presence of parental (systemic)
toxicity and there was no evidence of developmental toxicity in either
the rat or the rabbit studies. Therefore, OPP concludes that these
section 18 requests do not represent any unacceptable pre- or post-
natal risk to infants and children.
Using the conservative exposure assumptions described above, EPA
has concluded that aggregate exposure to pendimethalin from food will
utilize less than 2% of the RfD for infants and children. 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 pendimethalin 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 pendimethalin residues.
V. Other Considerations
The nature of the residue in plants is adequately understood. The
regulable residue in mint is pendimethalin and its 3,5-dinitrobenzyl
alcohol metabolite (CL 202,347), as per 40 CFR 180.361(a). Adequate
enforcement methodology, GC/ECD, is available in the Pesticide
[[Page 28360]]
Analytical Manual, Vol. II, to enforce the tolerance expression. The
combined residues of pendimethalin plus its regulated metabolite (CL
202,347) are not expected to exceed 0.1 ppm in/on fresh mint
(peppermint, spearmint) hay or 5.0 ppm in mint (peppermint, spearmint)
oil as a result of these section 18 uses. There are no Codex, Canadian,
or Mexican international residue limits established for residues of
pendimethalin in/on mint.
VI. Conclusion
Therefore, tolerances in connection with the FIFRA section 18
emergency exemptions are established for residues of pendimethalin in
fresh mint hay at 0.1 ppm and in mint oil at 5.0 ppm.
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 July 22, 1997, file written objections to any
aspect of this regulation (including the revocation provision) 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 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
The official record for this rulemaking, as well as the public
version, has been established for this rulemaking under docket control
number [OPP-300493] (including comments and data submitted
electronically as described below). A public version of this record,
including printed, paper versions of electronic comments, which does
not include any information claimed as CBI, is available for inspection
from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal
holidays. The official rulemaking record is located at the address in
``ADDRESSES'' at the beginning of this document.
Electronic comments can 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. Comment and data
will also be accepted on disks in Wordperfect 5.1 file format or ASCII
file format. All comments and data in electronic form must be
identified by the docket number [OPP-300493]. Electronic comments on
this proposed rule may be filed online at many Federal Depository
Libraries.
IX. Regulatory Assessment Requirements
This action finalizes a tolerance under section 408 of the FFDCA.
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). In addition, 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 special 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, pursuant to the Regulatory Flexibility Act (RFA) (5
U.S.C. 601 et seq.), the Agency 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 (46 FR 24950, May 4, 1981). In accordance with Small Business
Administration (SBA) policy, this determination will be provided to the
Chief Counsel for Advocacy of the SBA upon request.
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 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 in 40 CFR Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.
Dated: May 15, 1997.
Peter Caulkins,
Acting Director, Registration Divison, Office of Pesticide Programs.
Therefore, 40 CFR Chapter I is amended as follows:
PART 180 [AMENDED]
1. The authority citation for part 180 continues to read as
follows:
[[Page 28361]]
Authority: 21 U.S.C. 346a and 371.
2. Section 180.361 is amended as follows:
i. In paragraph (a) by adding a paragraph heading.
ii. In paragraph (b) by transferring the entry in the table for
``Peanuts, hulls'' to the table in paragraph (a), and by revising the
remainder of paragraph (b).
iii. In paragraph (c) by adding a paragraph heading.
iv. By adding and reserving paragraph (d).
Sec. 180.361 Pendimethalin, tolerances for residues.
(a) General. * * *
(b) Section 18 emergency exemptions. Time-limited tolerances are
established for residues of the herbicide pendimethalin in connection
with use of the pesticide under section 18 emergency exemptions granted
by EPA. The tolerances will expire and are revoked on the dates
specified in the following table:
------------------------------------------------------------------------
Parts per Expiration/
Commodity million Revocation Date
------------------------------------------------------------------------
Mint hay, fresh......................... 0.1 ppm 5/31/98
Mint oil................................ 5.0 ppm 5/31/98
------------------------------------------------------------------------
(c) Tolerances with regional registrations. * * *
(d) Indirect or inadvertent residues. [Reserved]
[FR Doc. 97-13643 Filed 5-22-97; 8:45 am]
BILLING CODE 6560-50-F
