[Federal Register Volume 62, Number 185 (Wednesday, September 24, 1997)]
[Rules and Regulations]
[Pages 49925-49931]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-25236]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 180 and 185

[OPP-300544; FRL-5740-8]
RIN 2070-AB78


Endothall; Pesticide Tolerances for Emergency Exemptions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes a time-limited tolerance for 
residues of endothall in or on canola seed. This action is in response 
to EPA's granting of an emergency exemption under section 18 of the 
Federal Insecticide, Fungicide, and Rodenticide Act authorizing use of 
the pesticide on canola in Minnesota. This regulation establishes a 
maximum permissible level for residues of endothall in this food 
commodity 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 tolerance will expire and is revoked on August 31, 1998.

DATES: This regulation is effective September 24, 1997. Objections and 
requests for hearings must be received by EPA on or before November 24, 
1997.

ADDRESSES: Written objections and hearing requests, identified by the 
docket control number, [OPP-300544], 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-300544], 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: <a href="/cdn-cgi/l/email-protection#402f30306d242f232b2534002530212d21292c6e2530216e272f36"><span class="__cf_email__" data-cfemail="107f60603d747f737b7564507560717d71797c3e7560713e777f66">[email protected]</span></a>. 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-300544]. 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: Andrea Beard, 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) 308-9356, e-mail: 
<a href="/cdn-cgi/l/email-protection#dab8bfbba8bef4bbb4bea8bfbb9abfaabbb7bbb3b6f4bfaabbf4bdb5ac"><span class="__cf_email__" data-cfemail="b3d1d6d2c1d79dd2ddd7c1d6d2f3d6c3d2ded2dadf9dd6c3d29dd4dcc5">[email protected]</span></a>.

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 a tolerance for 
residues of the herbicide endothall, in or on canola seed at 0.3 part 
per million (ppm). This tolerance will expire and is revoked on August 
31, 1998. EPA will publish a document in the Federal Register to remove 
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 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

[[Page 49926]]

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 Exemption for Endothall on Canola and FFDCA 
Tolerances

    The Applicant states that over the past several years, unusually 
cool and wet weather during the early part of the year has delayed 
planting of canola which allows smartweed to become established in 
fields, both competing with the canola plants and then contaminating 
the seed. The smartweed seed, about the same size as canola seed, 
cannot be removed using standard grain cleaning equipment. Increasing 
levels of conspicuous admixture result in lower grading of the canola 
seed, and thus lower prices for producers. In 1995, nearly all 
Minnesota canola was excluded from the export market due to dockage 
attributable to high contamination with smartweed and wild buckwheat, 
which significantly reduced grower revenues. The Applicant states that 
there are no other products registered for this use, nor are there 
effective alternative control measures available. The Applicant 
estimates that significant economic losses will be suffered by canola 
growers if endothall is not available for control of smartweed. EPA has 
authorized under FIFRA section 18 the use of endothall on canola for 
control of smartweeds in Minnesota. After having reviewed the 
submission, EPA concurs that emergency conditions exist for this state.
    As part of its assessment of this emergency exemption, EPA assessed 
the potential risks presented by residues of endothall in or on canola 
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 this tolerance will expire and is revoked on August 
31, 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 
canola 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 endothall meets EPA's 
registration requirements for use on canola or whether a permanent 
tolerance for this use would be appropriate. Under these circumstances, 
EPA does not believe that this tolerance serves as a basis for 
registration of endothall by a State for special local needs under 
FIFRA section 24(c). Nor does this tolerance serve as the basis for any 
State other than Minnesota 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 endothall, 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% or less of the RfD) is 
generally considered acceptable by EPA. EPA generally uses

[[Page 49927]]

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 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 3 
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 (Children 1 - 6 
years 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 endothall 
and to make a determination on aggregate exposure, consistent with 
section 408(b)(2), for a time-limited tolerance for residues of 
endothall on canola seed at 0.3 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

[[Page 49928]]

toxic effects caused by endothall are discussed below.
    1. Acute toxicity. An acute dietary risk endpoint has not been 
identified, and an acute risk assessment is not required.
    2. Short - and intermediate - term toxicity. For dermal short- and 
intermediate- term MOE calculations, the NOEL of 40.0 mg/kg/day (no 
effects seen at this, the Highest Dose Tested) was chosen from the 21-
day dermal toxicity study in rats.
    3. Chronic toxicity. EPA has established the RfD for endothall at 
0.02 milligrams/kilogram/day (mg/kg/day). This RfD is based on a 2-year 
feeding study in dogs with an NOEL of 2.0 mg/kg/day, using an 
uncertainty factor of 100. At the lowest observed effect level (LOEL) 
of 6.0 mg/kg/day, increased relative and absolute weight of the stomach 
and small intestine was observed.
    4. Carcinogenicity. Endothall has not yet been reviewed by the 
Cancer Peer Review Committee. However, review of available data 
indicate that tumors observed in both the rat and the mouse studies are 
within the historical control range for these species. Thus, there is 
no concern for carcinogenic effects at this time.

B. Exposures and Risks

    1. From food and feed uses. Tolerances have been established (40 
CFR 180.293) for the residues of endothall, in or on a variety of raw 
agricultural commodities, including rice grain and straw, potatoes, 
hops, cottonseed at levels from 0.05 to 0.1 ppm; and 40 CFR 180.319, 
interim tolerance for sugarbeets at 0.2 ppm. Risk assessments were 
conducted by EPA to assess dietary exposures and risks from endothall 
as follows:
    Chronic exposure and risk. In conducting this chronic dietary risk 
assessment, refinements used included percent of crop treated figures 
for all crops except canola and sugar beets. Aside from this, the 
conservative assumptions were made that 100% of the crops would have 
residues at tolerance levels. Using these conservative assumptions, the 
ARC estimates occupy the following percentages of the RfD: Overall U.S. 
Population, 1.1%; Nursing Infants <1 Year Old, 0.6%; Non-Nursing 
Infants <1 Year Old, 1.5%; Children Age 1-6 Years (highest exposed 
subgroup), 2.1%; and Children 7-12 Years Old, 1.6%. Although these 
estimates are well below levels of concern, additional refinement using 
anticipated residue levels and percent of crop treated information for 
all crops would result in much lower dietary exposure estimates.
    2. From drinking water. There is an interim tolerance for residues 
of endothall in potable water at 0.2 ppm, and EPA has also established 
a Maximum Contaminant Level (MCL) for water at 0.1 mg/L.
     Chronic exposure and risk. Chronic exposure levels for the U.S. 
population and children were calculated assuming concentrations at the 
MCL of 100.0 <greek-m>g/L in drinking water; adult and child body 
weights of 70 and 10 kg, respectively; and adult and child drinking 
water consumption of 2 and 1 L per day, respectively. Based on these 
assumptions, adult exposure was calculated to be 2.9 x 10<SUP>-3</SUP> 
mg/kg/day, and child exposure to be 1.0 x 10<SUP>-2</SUP> mg/kg/day. 
These exposure values correspond to 14.3% of the RfD for adults, and 
50.0% of the RfD for children.
    3. From non-dietary exposure. Endothall is currently registered for 
use on the following residential non-food sites: Granular formulations 
of endothall are applied to lakes and ponds that have recreational 
uses. Concentrations of endothall ranging from 0.5 to 5 mg/L are used 
to control various aquatic weeds.
     i. Chronic exposure and risk. Chronic non-dietary exposure is not 
expected with this use. Therefore, it is not necessary to conduct a 
chronic risk assessment, in association with the non-dietary exposure, 
which is expected to be short- and intermediate-term. This risk is 
discussed in the following paragraph.
    ii. Short- and intermediate-term exposure and risk. The non-dietary 
swimmer exposure of a child (1-6 years), while swimming in water 
treated with this chemical is estimated as follows: Dermal Exposure = 
(Concentration of endothall) x (Surface area of child) x (hours 
exposed) x (body weight (kg)). Assumptions were used of 0.5 - 5 mg/L 
endothall concentrations in the water, surface area and body weight of 
the child 9,000 cm<SUP>2,</SUP> and 22 kg, respectively. Based upon 
these assumptions, dermal exposure is estimated at a range of 0.0044 to 
0.044 mg/kg/day. Oral Exposure = (Concentration of endothall) x 
(Ingestion rate of water) x (exposure time) / (body weight(kg)). 
Assumptions were 0.05 L/hr ingestion, 5 hr/day exposure time, and 22 kg 
bodyweight. Based on these assumptions, oral exposure is estimated at a 
range of 0.0057 to 0.057 mg/kg/day. Total Exposure, both dermal and 
oral, for a child 1-6 years old, is estimated at 0.01 to 0.1 mg/kg/day. 
From these exposure estimates, the MOE for short-term and intermediate-
term exposure is calculated to be a range of 400 to 4,000.
    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 endothall has a common mechanism of toxicity with other 
substances or how to include this pesticide in a cumulative risk 
assessment. Unlike other pesticides

[[Page 49929]]

for which EPA has followed a cumulative risk approach based on a common 
mechanism of toxicity, EPA cannot at this time determine whether 
endothall produces a toxic metabolite produced by other substances. For 
the purposes of this tolerance action, therefore, EPA has not assumed 
that endothall has a common mechanism of toxicity with other 
substances.

C. Aggregate Risks and Determination of Safety for U.S. Population

    1. Chronic risk. Using the ARC exposure assumptions described 
above, EPA has concluded that aggregate exposure to endothall from food 
and drinking water will utilize 15.4% of the RfD for the U.S. 
population. The major identifiable subgroup with the highest aggregate 
exposure is Children 1 to 6 Years 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 endothall 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 acute aggregate exposure to 
endothall residues.
    2. 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.
    Based upon assumptions given above, the MOEs for adults from 
exposures contributed by food plus drinking water plus swimming 
exposure, range from 384 to 3,033. For children, the MOEs range from 
359 to 1,950. Since these MOEs are well above the acceptable level of 
100, EPA concludes that there is reasonable certainty that no harm will 
result from short- and intermediate-term exposure to endothall 
residues.

D. 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 endothall, EPA considered data from 
developmental toxicity studies in the rat and rabbit 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 maternal pesticide exposure during gestation. 
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 100-
fold safety factor (usually 100 for combined inter- and intra-species 
variability)) and not the additional tenfold safety 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 safety factor.
    ii. Developmental toxicity studies. In the developmental study in 
rats, the maternal (systemic) NOEL was 12.5 mg/kg/day, based upon 
decreased body weight gain at the LOEL of 25.0 mg/kg/day. The 
developmental (fetal) NOEL was 25.0 mg/kg/day, the highest dose tested.
    iii. Reproductive toxicity study. In the 2-generation reproductive 
toxicity study in rats, the parental (systemic) NOEL was not determined 
since there were proliferative lesions of the gastric epithelium in 
both sexes at the lowest dose tested (2.0 and 2.3 mg/kg/day for males 
and females respectively). The developmental/reproductive (pup) NOEL 
was 9.4 mg/kg/day, based on decreased pup body weights (both sexes) at 
the LOEL of 60.0 mg/kg/day.
    iv. Pre- and post-natal sensitivity. The available developmental 
and reproductive toxicity data available do not indicate that there are 
pre- or post-natal toxicity concerns for infants and children.
    v. Conclusion. Based on the currently available developmental and 
reproductive toxicity studies discussed above and best scientific 
judgment of EPA scientists, there does not appear to be an extra 
sensitivity for pre- or post-natal effects, and an additional tenfold 
safety factor is not warranted.
    2. Chronic risk. Using the conservative exposure assumptions 
described above, EPA has concluded that aggregate exposure to endothall 
from food and drinking water will utilize 52.1% 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 endothall 
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 endothall residues.
    3. Short- or intermediate-term risk. Granular formulations of 
endothall are applied to lakes and ponds that have recreational uses. 
Concentrations of endothall ranging from 0.5 to 5 mg/L are used to 
control various aquatic weeds.
     Short- and intermediate-term exposure and risk. The non-dietary 
swimmer exposure estimate for a child (1-6 years), while swimming in 
water treated with this chemical, through both dermal and oral 
exposure, results in MOEs from 400 to 4,000 (further discussed above).

V. Other Considerations

A. Metabolism In Plants and Animals

    The qualitative nature of the residues of endothall in plants 
appears to be adequately understood; the nature of the residue in 
animals is adequately understood based on acceptable studies with 
lactating goats and laying hens. The residue to be regulated is 
endothall per se, as stated in 40 CFR 180.293 .

B. Analytical Enforcement Methodology

    Adequate analytical methods are available for tolerance enforcement 
in plant commodities ( a GC method with nitrogen detection is available 
in the Pesticide Analytical Manual (PAM) Vol. II, as Method I.) No 
tolerances have been established for animal commodities, or are 
required with this section 18 use; therefore, no analytical methods are 
required for livestock commodities.

C. Magnitude of Residues

    Residues of endothall are not expected to exceed 0.3 ppm in canola 
and in its processed products canola oil and meal, as a result of this 
use. Secondary resides are not expected in animal commodities.

D. International Residue Limits

    There are no Codex, Canadian, or Mexican Maximum Residue Levels 
(MRLs) established for endothall on canola.

[[Page 49930]]

E. Rotational Crop Restrictions

    There are no rotational crop restrictions with this use or on the 
federal label for endothall.

VI. Conclusion

    Therefore, the tolerance is established for residues of endothall 
in canola seed at 0.3 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 November 24, 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-300544] (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 Hwy., Arlington, VA.
    Electronic comments may be sent directly to EPA at:
    <a href="/cdn-cgi/l/email-protection#573827277a3338343c3223173227363a363e3b7932273679303821"><span class="__cf_email__" data-cfemail="59362929743d363a323c2d193c293834383035773c2938773e362f">[email protected]</span></a>.


    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 under FFDCA 
section 408(1)(6). 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 under FFDCA section 408 (l)(6), such as the 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 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 Parts 180 and 185

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Food additives, Pesticides and pests, 
Reporting and recordkeeping requirements.


[[Page 49931]]


    Dated: September 12, 1997.

Daniel Barolo,
Director, Office of Pesticide Programs.
    Therefore, 40 CFR chapter I 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. 180.293:
    i. By designating the existing text as paragraph (a)(1) and adding 
a heading to paragraph (a).
    ii. By adding paragraph (b).
    iii. By adding and reserving paragraphs (c) and (d).
    Section 180.293, as amended, reads as follows:


Sec. 180.293 Endothall; tolerances for residues.

    (a) General. * * *
    (b) Section 18 emergency exemptions. Time-limited tolerances are 
established for the residues of the herbicide endothall, in connection 
with use of the pesticide under section 18 emergency exemptions granted 
by EPA. The tolerances will expire on the dates specified in the 
following table:

                                                                        
------------------------------------------------------------------------
                                                          Expiration/   
            Commodity              Parts per million    Revocation Date 
------------------------------------------------------------------------
Canola, seed....................  0.3                 8/31/98           
------------------------------------------------------------------------

    (c) Tolerances with regional registrations. [Reserved]
    (d) Indirect or inadvertent residues. [Reserved]

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. 185.2650  [Removed]

    b. In Sec. 185.2650:
    i. By desginating the existing text as paragraph (a)(2) to 
Sec. 180.293.
    ii. By removing Sec. 185.2650.

[FR Doc. 97-25236 Filed 9-23-97; 8:45 am]
BILLING CODE 6560-50-F


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