Tebuconazole; Pesticide Tolerance for Emergency Exemption
[Federal Register: May 26, 1999 (Volume 64, Number 101)]
[Rules and Regulations]
[Page 28377-28384]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr26my99-12]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300855; FRL-6079-1]
RIN 2070-AB78
Tebuconazole; Pesticide Tolerance for Emergency Exemption
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes a time-limited tolerance for
residues of tebuconazole in or on garlic. 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 garlic. This regulation establishes a maximum
permissible level for residues of tebuconazole 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 June 30, 2000.
DATES: This regulation is effective May 26, 1999. Objections and
requests for hearings must be received by EPA on or before July 26,
1999.
ADDRESSES: Written objections and hearing requests, identified by the
docket control number [OPP-300855], 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-300855], must also be submitted to: Public Information and
Records Integrity Branch, Information Resources and Services Division
(7502C), 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. 119, Crystal Mall #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@epa.gov. Copies of electronic 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 5.1/6.1
or ASCII file format. All copies of electronic objections and hearing
requests must be identified by the docket control number [OPP-300855].
No Confidential Business Information (CBI) should be submitted through
e-mail. Copies of electronic 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 (7505C), Office of Pesticide Programs,
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460.
Office location, telephone number, and e-mail address: Rm. 271, Crystal
Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA, 703-308-9362; e-
mail: schaible.stephen@epa.gov.
SUPPLEMENTARY INFORMATION: EPA, on its own initiative, pursuant to
sections 408 and (l)(6) of the Federal Food, Drug, and Cosmetic Act
(FFDCA), 21 U.S.C. 346a and (l)(6), is establishing a tolerance for
residues of the fungicide tebuconazole, in or on garlic at 0.1 part per
million (ppm). This tolerance will expire and is revoked on June 30,
2000. EPA will publish a document in the Federal Register to remove the
revoked tolerance from the Code of Federal Regulations.
I. Background and Statutory Findings
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 in this preamble 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. . . .''
[[Page 28378]]
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 tolerances to set binding precedents for the
application of section 408 and the new safety standard to other
tolerances and exemptions.
II. Emergency Exemption for Tebuconazole on Garlic and FFDCA
Tolerances
While garlic rust is usually a disease of minor concern in
California, it appeared as a serious pest problem in several garlic
growing areas of the state in the 1997-98 growing season. The mild
winter that year allowed the pathogen to survive the winter and cause
infection early in the season. No fungicide is specifically registered
for control of rust on garlic. The fungicides registered for use on
garlic are not effective at controlling the disease under high pest
pressure. Data presented by the state indicate that tebuconazole is
highly effective at controlling the disease. EPA has authorized under
FIFRA section 18 the use of tebuconazole on garlic for control of
garlic rust in California. 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 tebuconazole in or on
garlic. In doing so, EPA considered the 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 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 June 30, 2000,
under FFDCA section 408(l)(5), residues of the pesticide not in excess
of the amounts specified in the tolerance remaining in or on garlic
after that date will not be unlawful, provided the pesticide is applied
in a manner that was lawful under FIFRA, and the residues do not exceed
a level that was authorized by this tolerance at the time of that
application. 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 tebuconazole meets EPA's
registration requirements for use on garlic 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 tebuconazole 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 California to use this pesticide on this crop under
section 18 of FIFRA without following all provisions of EPA's
regulations implementing section 18 as identified in 40 CFR part 166.
For additional information regarding the emergency exemption for
tebuconazole, contact the Agency's Registration Division at the address
provided under the ``ADDRESSES'' section.
III. Aggregate Risk Assessment and Determination of Safety
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 and a complete description of
the risk assessment process, see the final rule on Bifenthrin Pesticide
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7) .
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
tebuconazole and to make a determination on aggregate exposure,
consistent with section 408(b)(2), for a time-limited tolerance for
residues of tebuconazole on garlic at 0.1 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 tebuconazole are
discussed in this unit.
B. Toxicological Endpoint
1. Acute toxicity. The acute reference dose (RfD) of 0.1
milligrams/kilogram/day (mg/kg/day) for tebuconazole was established
based on a developmental toxicity study in mice with a no observed
adverse effect level (NOAEL) of 10 mg/kg/day for developmental
toxicity. At the lowest observed adverse effect level (LOAEL) of 30 mg/
kg/day, an increased incidence of runts (fetuses weighing less than 1.3
gram) were observed. An uncertainty factor of 100 was applied to the
NOAEL to calculate the acute RfD of 0.1 mg/kg/day. EPA has determined
that the 10x factor to account for enhanced susceptibility of infants
and children (as required by FQPA) should be retained. This
determination is based on the results of the developmental toxicity
study in mice used to establish the acute RfD, other developmental
toxicity studies in mice, rats and rabbits and the structural
relationship of tebuconazole to several other triazole pesticides which
also have been shown to induce developmental toxicity in rats and/or
rabbits. For acute dietary exposure, EPA determined that the 10x safety
factor is applicable to the subpopulations females (13+ years), as well
as infants and children because the effects seen were developmental and
are presumed to occur following ``acute'' exposures. For subpopulations
other than females (13+ years), infants and children, a toxicological
endpoint was not identified. Application of the 10x safety factor for
enhanced susceptibility of infants and children to the acute RfD of 0.1
mg/kg/day results in an acceptable acute dietary exposure (food plus
water) of 10% or less of the acute RfD.
2. Short-and intermediate-term toxicity. Toxicological endpoints
for short- or intermediate-term dermal toxicity were not identified.
Adverse systemic effects were not observed in dermal developmental
toxicity studies in mice or rats at the limit dose of 1,000
[[Page 28379]]
mg/kg/day or in a 21-day dermal toxicity study in rabbits at the limit
dose of 1,000 mg/kg/day. Therefore, risk assessments for short- or
intermediate-term dermal exposure were not conducted.
A NOAEL of 0.0106 mg/liter/day (equivalent to 2.9 mg/kg/day) was
identified as the toxicological endpoint for short- and intermediate-
term (and chronic) inhalation toxicity based on a 21-day inhalation
toxicity study in rats. At the LOAEL of 0.1558 mg/liter/day,
piloerection and increased liver O-demethylase and N-demethylase
activity were observed in both males and females. EPA determined that
the 10x safety factor to account for enhanced susceptibility of infants
and children (as required by FQPA) is not applicable for inhalation
toxicity for the currently registered residential exposures to
tebuconazole. A Margin of Exposure (MOE) of 100 or more for short- or
intermediate-term non-dietary risk is acceptable for all
subpopulations.
3. Chronic toxicity. EPA has established the RfD for tebuconazole
at 0.03 (mg/kg/day). This RfD is based on a 1-year chronic feeding
study in dogs in which the NOAEL was 100 ppm (2.96 mg/kg/day in males
and 2.94 mg/kg/day in females) and the LOAEL was 150 ppm (4.39 mg/kg/
day in males and 4.45 mg/kg/day in females), based on histopathological
changes in the adrenal gland (hypertrophy of the zona fasciculata and
fatty changes in the zona glomerulosa in both sexes and lipid
hyperplasia in the cortex in males). An uncertainty factor of 100 was
used to account for inter-species extrapolation and intra-species
variability. EPA determined that the 10x factor for enhanced
susceptibility of infants and children (as required by FQPA) is not
applicable for chronic dietary exposure. The developmental effects
which contributed to the decision to retain the 10x factor for acute
dietary exposure are considered to be acute effects; maternal effects
in those same studies were minimal. Additionally, the NOAEL on which
the RfD is based is the lowest NOAEL in the toxicology data base for
this chemical. A chronic dietary exposure (food plus water) of 100% or
less of the chronic RfD is acceptable for all subpopulations.
4. Carcinogenicity. Tebuconazole is classified as a Group C
(possible human) carcinogen. This decision was primarily based on
results in a 91-week carcinogenicity study in mice in which the
following effects were observed:
1. A statistically significant increase in the incidence of
hepatocellular adenomas, carcinomas and combined adenomas/carcinomas in
male mice at the highest dose tested (279 mg/kg/day).
2. A statistically significant increase in the incidence of
hepatocellular carcinomas and combined adenomas/carcinomas in female
mice at the highest dose tested (366 mg/kg/day). In addition,
tebuconazole is structurally related to several other triazole
pesticides that produce similar liver tumors in mice. For the purpose
of carcinogenic risk assessment, the RfD methodology is used to
estimate human risk.
C. Exposures and Risks
1. From food and feed uses. Tolerances have been established (40
CFR 180.474) for the residues of tebuconazole, in or on a variety of
raw agricultural commodities. Tolerances have been established for milk
and meat byproducts in connection with use of tebuconazole under a
previous section 18. Risk assessments were conducted by EPA to assess
dietary exposures and risks from tebuconazole 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 a 1-day or single exposure. An acute dietary endpoint of concern was
identified for subpopulations females (13+ years), as well as infants
and children.
An acute dietary (food only) probablistic risk analysis submitted
in conjunction with another action was used to estimate acute dietary
risk. The following assumptions were utilized in the Monte Carlo
analysis:
1. Percent crop treated (PCT) data were used for all commodities.
2. Maximum residue levels from crop field trials for single serving
commodities such as bananas and peaches were utilized.
3. Average residue levels from crop field trials were used for
blended commodities such as fruit juices, grains and oils.
4. Anticipated residue levels for ruminant commodities were
calculated using a livestock diet constructed using anticipated residue
levels for livestock feed items. This analysis is considered to be
highly refined. This analysis was run with 2,000 iterations. The
results of the Monte Carlo analysis indicate that the percent of acute
RfD for all children and infants subgroups as well as females 13+ years
old are all below 10% of the RfD nursing infants (<1 year), 7%; non-
nursing infants (<1 year), 7%; children (1 to 6 years) 9%, children (7
to 12 years) 3%; all infants (<1 year), 7%; females (13 years plus),
3%.
Section 408(b)(2)(E) authorizes EPA to use available data and
information on the anticipated residue levels of pesticide residues in
food and the actual levels of pesticide chemicals that have been
measured in food. If EPA relies on such information, EPA must require
that data be provided 5 years after the tolerance is established,
modified, or left in effect, demonstrating that the levels in food are
not above the levels anticipated. Following the initial data
submission, EPA is authorized to require similar data on a time frame
it deems appropriate. As required by section 408(b)(2)(E), EPA will
issue a data call-in for information relating to anticipated residues
to be submitted no later than 5 years from the date of issuance of this
tolerance.
Section 408(b)(2)(F) states that the Agency may use data on the
actual percent of food treated for assessing chronic dietary risk only
if the Agency can make the following findings: That the data used are
reliable and provide a valid basis to show what percentage of the food
derived from such crop is likely to contain such pesticide residue;
that the exposure estimate does not underestimate exposure for any
significant subpopulation group; and if data are available on pesticide
use and food consumption in a particular area, the exposure estimate
does not understate exposure for the population in such area. In
addition, the Agency must provide for periodic evaluation of any
estimates used. To provide for the periodic evaluation of the estimate
of PCT as required by section 408(b)(2)(F), EPA may require registrants
to submit data on PCT.
The Agency used PCT information as follows:
PCT refinements were assumed for all commodities evaluated in the
probablistic risk assessment. For published uses, PCT data were based
on information obtained from the registrant and were derived from Doane
Marketing Research and USDA National Agricultural Statistics Service
(NASS). For those commodities being requested under section 18, total
U.S. acreage treated under section 18 was aggregated for each crop and
compared to total acreage grown in the U.S. to derive a national PCT
estimate.
The Agency believes that the three conditions, discussed in section
408 (b)(2)(F) concerning the Agency's responsibilities in assessing
acute dietary risk findings, have been met. The PCT estimates are
derived from Federal and private market survey data, which are reliable
and have a valid basis. Typically, a range of estimates are supplied
and the upper end of this
[[Page 28380]]
range is assumed for the exposure assessment. By using this upper end
estimate of the PCT, the Agency is reasonably certain that the
percentage of the food treated is not likely to be underestimated. The
regional consumption information and consumption information for
significant subpopulations is taken into account through EPA's
computer-based model for evaluating the exposure of significant
subpopulations including several regional groups. Use of this
consumption information in EPA's risk assessment process ensures that
EPA's exposure estimate does not understate exposure for any
significant subpopulation group and allows the Agency to be reasonably
certain that no regional population is exposed to residue levels higher
than those estimated by the Agency. Other than the data available
through national food consumption surveys, EPA does not have available
information on the regional consumption of food to which tebuconazole
may be applied in a particular area.
ii. Chronic exposure and risk. The Agency conducted a chronic
dietary exposure analysis and risk assessment. The analysis evaluated
individual food consumption as reported by respondents in the USDA
1977-78 Nationwide Food Consumption Survey (NFCS) and accumulates
exposure to the chemical for each commodity. In conducting the chronic
dietary risk assessment, the Agency made the very conservative
assumption that 100% of every commodity evaluated will contain residues
and those residues will be at tolerance level; this assumption results
in an overestimation of human dietary exposure. Thus, in making a
safety determination for this time-limited tolerance, the Agency is
taking into account this conservative exposure assessment.
The existing tebuconazole tolerances published, pending, and
including the necessary section 18 tolerance(s) result in a Theoretical
Maximum Residue Contribution (TMRC) that is equivalent to percentages
of the RfD below 100% for all subgroups i.e., U.S. population, 11% and
non-nursing infants (<1 year old), the most highly exposed subgroup,
37%.
2. From drinking water. Based on present data available to the
Agency, tebuconazole is persistent and relatively immobile. There are
no established Maximum Contaminant Level or health advisory levels for
residues of tebuconazole in drinking water. Monitoring data for
residues of tebuconazole in surface and ground water are not available.
Tebuconazole is not included in the Pesticides in Ground Water Database
(US EPA, 1992), and it was not an analyte in the National Pesticide
Survey (US EPA, 1990).
EPA estimated exposure for tebuconazole for both surface and ground
water based on available modeling. Environmental concentrations for
surface water were estimated using modeling from Generic Estimated
Environmental Concentration (GENEEC). For surface water, the maximum
concentrations were used for acute risk calculations, the annual means
(1-10 years) for chronic risk calculations. Current Agency policy
allows that a factor of 3 be applied to GENEEC model values when
determining whether or not a level of concern has been exceeded. If the
GENEEC model value is <ls-thn-eq> 3 times the drinking water level of
comparison (DWLOC), the pesticide is considered to have passed the
screen. Acute and chronic ground water concentrations were estimated
using the Screening Concentration in Ground Water (SCI-GROW) model. For
the purposes of the screening level assessment, the maximum and average
annual concentrations in ground water are not believed to vary
significantly. DWLOCs will be compared directly to SCI-GROW values.
i. Acute exposure and risk. DWLOCs were calculated for acute
exposures to tebuconazole in surface and ground water for females 13+
years old and children (1-6 years old). Relative to an acute toxicity
endpoint, the acute dietary food exposure (from the probablistic
analysis) was subtracted from the ratio of the acute NOAEL to the
appropriate percentage acute RfD to obtain the acceptable acute
exposure to tebuconazole in drinking water. DWLOCs were then calculated
from this acceptable exposure using default body weights (60 kg for
females and 10 kg for children) and drinking water consumption figures
(2 liters for females 1 liter for children). Based on these
calculations EPA's DWLOC for acute dietary risk is 14 parts per billion
(ppb) for children (1-6 years old) and 200 ppb for females 13+ years
old.
Maximum concentrations of tebuconazole in surface and ground water
are estimated to be 14 ppb and 0.3 ppb, respectively. The maximum
estimated concentrations of tebuconazole in surface and ground water do
not exceed EPA's levels of concern for acute exposure in drinking water
for the females 13+ and children.
ii. Chronic exposure and risk. EPA has calculated DWLOCs for
chronic exposures to tebuconazole in surface and ground water. To
calculate the DWLOC for chronic exposures relative to a chronic
toxicity endpoint, the chronic dietary food exposure was subtracted
from the chronic RfD (0.03 mg/kg/day) to obtain the acceptable chronic
exposure to tebuconazole in drinking water. DWLOCs were then calculated
from this exposure using default body weights (70 kg for U.S.
population, 60 kg for females 10 kg for children) and drinking water
consumption figures (2 liters U.S. population females 1 liter
children). Based on these calculations EPA's DWLOCs for chronic risk
are 950 ppb for the U.S. population, 780 ppb for females and 190 ppb
for non-nursing infants (<1 year old).
Estimated annual average concentrations of tebuconazole in surface
water and ground water are 10 ppb and 0.3 ppb, respectively. The
estimated annual average concentrations of tebuconazole in surface and
ground water are less than EPA's levels of concern for chronic exposure
in drinking water.
3. From non-dietary exposure. No short- or intermediate-term dermal
toxicological endpoints were identified. Tebuconazole's registered
residential uses are for the formulation of wood-based composite
products, wood products for in-ground contact, plastics, exterior
paints, glues and adhesives. Currently, the only residential end-use
products on the market are for exterior treated wood use. Exposure via
incidental ingestion (by children) and inhalation are not a concern for
these products which are used outdoors. No paints or other end-use
products containing tebuconazole are available for interior use.
Accordingly, residential exposure is not expected at this time.
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.''
EPA does not have, at this time, available data to determine
whether tebuconazole 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,
tebuconazole 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 tebuconazole has a
[[Page 28381]]
common mechanism of toxicity with other substances. For more
information regarding EPA's efforts to determine which chemicals have a
common mechanism of toxicity and to evaluate the cumulative effects of
such chemicals, see the final rule for Bifenthrin Pesticide Tolerances
(62 FR 62961, November 26, 1997).
D. Aggregate Risks and Determination of Safety for U.S. Population
1. Acute risk. A toxicological endpoint was identified for acute
dietary risk assessments for subpopulations females (13+ years),
infants and children. The 10x safety factor for enhanced susceptibility
of infants and children as required by FQPA is applicable for all of
these subgroups. Therefore, 10% or less of the acute RfD of 0.1 mg/kg/
day results in an acceptable acute dietary exposure (food plus water).
An acute dietary (food only) probablistic risk analysis resulted in
3% of the acute RfD utilized for females (13+ years). The maximum
estimated concentrations of tebuconazole in surface and ground water do
not exceed EPA's levels of concern for acute exposure in drinking water
for the females 13+. Currently the only residential end-use products on
the market are for exterior treated wood use. Exposure via incidental
ingestion (by children) and inhalation are not a concern for these
products which are used outdoors. No paints or other end-use products
containing tebuconazole are available for interior use. Accordingly
residential exposure is not expected with these uses. Therefore, EPA
concludes with reasonable certainty that residues of tebuconazole do
not contribute significantly to the aggregate acute risk at the present
time.
2. Chronic risk. Using the TMRC exposure assumptions described in
this unit, EPA has concluded that aggregate exposure to tebuconazole
from food will utilize 11% of the RfD for the U.S. population. The
major identifiable subgroup with the highest aggregate exposure is non-
nursing infants (< 1 yr.), 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. Estimated
environmental concentrations of tebuconazole in surface water and
ground water do not exceed chronic DWLOCs calculated by the Agency;
therefore, EPA does not expect the aggregate exposure to exceed 100% of
the RfD.
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.
No short- or intermediate-term dermal toxicological endpoints were
identified. Also, no residential exposure is expected from the current
residential uses. Thus, no risk assessments were conducted for
residential exposure. Therefore, EPA concludes with reasonable
certainty that tebuconazole does not contribute significantly to the
aggregate shortand intermediate-term risk at the present time.
4. Aggregate cancer risk for U.S. population. Tebuconazole is
classified as a Group C (possible human) carcinogen. Since, for the
purpose of carcinogenic risk assessment the Reference Dose (RfD)
methodology was used, the discussion for chronic risk (11% of RfD
utilized) above applies to cancer risk as well. Therefore, EPA
concludes with reasonable certainty that tebuconazole does not
contribute significantly to the aggregate cancer risk at the present
time.
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
from aggregate exposure to tebuconazole residues.
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 tebuconazole, 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 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 data base 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 (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. In two associated oral
developmental toxicity studies in mice, the maternal NOAEL was 10 mg/
kg/day and the LOAEL was 20 mg/kg/day, based on decreased hematocrit
and effects in the liver. The developmental toxicity NOAEL was 10 mg/
kg/day and the LOAEL was 30 mg/kg/day, based on increased numbers of
runts (fetuses weighing less than 1.3 gram). In addition, at 100 mg/kg/
day, frank malformations in the skull, brain and spinal column and a
reduced rate of ossification in the cranium were observed. In a dermal
developmental toxicity study in mice, no toxicologically significant
maternal toxicity or developmental toxicity was observed at the limit
dose of 1,000 mg/kg/day.
In an oral developmental toxicity study in rats, the maternal NOAEL
was 30 mg/kg/day and the LOAEL was 60 mg/kg/day, based on increased
liver weight. The developmental toxicity NOAEL was 30 mg/kg/day and the
LOAEL was 60 mg/kg/day, based on delayed ossification of several bones
and increased numbers of fetuses with supernumerary ribs. In addition,
at 120 mg/kg/day, increased resorptions, decreased fetal body weights
and frank malformations in two fetuses (missing tail, agnatha,
microtomia and anophthalmia) were observed. In a dermal developmental
toxicity study in rats, no toxicologically significant maternal
toxicity or developmental toxicity was observed at the limit dose of
1,000 mg/kg/day.
In an oral developmental toxicity study in rabbits, the maternal
NOAEL was 30 mg/kg/day and the LOAEL was 100 mg/kg/day, based on
decreased body weight gain and decreased food consumption during the
dosing period. The developmental toxicity NOAEL was 30 mg/kg/day and
the LOAEL was 100 mg/kg/day, based on increased postimplantation loss,
increased frank malformations, hydrocephalus and delayed ossification
of bones. In another oral developmental toxicity study in rabbits, the
maternal NOAEL was <10
[[Page 28382]]
mg/kg/day and the LOAEL was 10 mg/kg/day, based on increased incidences
of single cell necrosis (minimal severity) in liver cells. The maternal
NOAEL from this study was not used to determine the acute RfD because
single cell necrosis was not considered to result from a single
exposure. The developmental toxicity NOAEL was 30 mg/kg/day and the
LOAEL was 100 mg/kg/day, based on increased postimplantation loss,
decreased fetal body weights, increased percentage of fetuses with
abnormalities (including runts, hemidiaphragm, limb abnormalities and
neural tube defects characterized as meningocoele and spina bifida) and
delayed ossification of bones.
iii. Reproductive toxicity study. In a 2-generation reproduction
study in rats, the parental (systemic) toxicity NOAEL was 15 mg/kg/day
and the LOAEL was 50 mg/kg/day, based on loss of hair, decreased body
weights, decreased food consumption, increased severity of spleen
hemosiderosis and decreased liver and kidney weights. For offspring
toxicity, the NOAEL was 15 mg/kg/day and the LOAEL was 50 mg/kg/day,
based on decreased pup body weights from birth through weeks 3-4 in all
litter groups.
iv. Pre-and postnatal sensitivity. The above studies meet the
standard toxicology data requirements, as required for a food-use
chemical, in 40 CFR part 158. However, after evaluation of the findings
in these studies, particularly with respect to effects on the fetal
nervous system, together with a consideration of neurotoxic effects
observed in several other developmental toxicity studies on
structurally related triazole pesticides, the Agency requested a
postnatal developmental neurotoxicity study in rats (Guideline 83-6) be
conducted. The EPA notes effects on the nervous system of fetuses in
studies on tebuconazole occurred only at doses of 100 mg/kg/day or
higher--i.e., at doses at least ten-fold higher than the developmental
toxicity NOAEL (10 mg/kg/day) to be used for the assessment of acute
dietary risk.
On the basis of comparative NOAELs and LOAELs, it was determined
there was no indication of increased susceptibility of the offspring of
mice, rats or rabbits resulting from prenatal and/or postnatal exposure
to tebuconazole. However, the maternal effects observed in the
developmental toxicity studies at the LOAEL were of minimal concern and
did not increase substantially in severity at higher doses, whereas the
developmental effects at the LOAEL were pronounced and at higher doses
were quite severe (including frank malformations) in mice (at 100 mg/
kg/day), rats (at 120 mg/kg/day) and rabbits (at 100 mg/kg/day). Based
on a consideration of all the above findings, the Agency retained the
10x factor for enhanced susceptibility to infants and children. The 10x
factor is applicable to acute dietary exposures for the subpopulations
females (13+ years), infants and children. The 10x factor for enhanced
sensitivity of infants and children is not applicable to chronic
exposure analysis.
v. Conclusion. There is a complete toxicity data base for
tebuconazole and exposure data are complete or estimated based on data
that reasonably accounts for potential exposures.
2. Acute risk. An acute dietary (food only) probablistic risk
analysis resulted in the following percentages for the acute RfD:
nursing infants (<1 year), 7%; non-nursing infants (<1 year), 7%;
children (1 to 6 years) 9%, children (7 to 12 years) 3%; and all
infants (<1 year), 7%. The maximum estimated concentrations of
tebuconazole in surface and ground water do not exceed EPA's levels of
concern for acute exposure in drinking water for children. Currently,
the only residential end-use products on the market are for exterior
treated wood use. Exposure via incidental ingestion (by children) and
inhalation are not a concern for these products which are used
outdoors. No paints or other end-use products containing tebuconazole
are available for interior use. Accordingly residential exposure is not
expected with these uses. Therefore, EPA concludes with reasonable
certainty that residues of tebuconazole do not contribute significantly
to the aggregate acute risk at the present.
3. Chronic risk. Using the exposure assumptions described in this
unit, EPA has concluded that aggregate exposure to tebuconazole from
food will utilize up to 37% 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. As stated above, residential exposure to tebuconazole is not
expected for the currently registered uses. Estimated environmental
concentrations of tebuconazole in surface water and ground water do not
exceed chronic DWLOCs calculated by the Agency; therefore, EPA does not
expect the aggregate exposure to exceed 100% of the RfD.
4. Short- or intermediate-term risk. As stated above, residential
exposure to tebuconazole is not expected for the currently registered
uses.
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to infants and children from aggregate exposure to tebuconazole
residues.
IV. Other Considerations
A. Metabolism In Plants and Animals
The nature of the residue in plants is understood based on
metabolism studies in grapes, wheat and peanuts. For the purpose of
this section 18 only, the nature of the residue in garlic is considered
to be adequately understood. The residue of concern in plants is
tebuconazole per se.
B. Analytical Enforcement Methodology
Method 101341, a GC/NPD method, is adequate to enforce the
tolerance expression. The method may be requested from: Calvin Furlow,
PRRIB, IRSD (7502C), Office of Pesticide Programs, Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460. Office
location and telephone number: Rm 101FF, Crystal Mall #2, 1921
Jefferson Davis Hwy., Arlington, VA, (703) 305-5229.
C. Magnitude of Residues
No residue data were provided for garlic. Residue data were
translated from dry bulb onion data generated in Mexico. Based on these
data, residues of tebuconazole are not expected to exceed 0.1 ppm on
garlic as a result of the proposed section 18 use.
D. International Residue Limits
There are no Codex, Canadian, or Mexican maximum residue limits
(MRLs) for residues of tebuconazole in/on garlic. International
harmonization is thus not an issue for this time-limited tolerance.
E. Rotational Crop Restrictions
A plant back interval of 120 days after last application for crops
not listed on the label is required.
V. Conclusion
Therefore, the tolerance is established for residues of
tebuconazole in garlic at 0.1 ppm.
VI. Objections and Hearing Requests
The new FFDCA section 408(g) provides essentially the same process
for persons to ``object'' to a tolerance regulation 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
[[Page 28383]]
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 26, 1999, 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 under the ``ADDRESSES'' section (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). EPA is authorized to waive any fee requirement
``when in the judgement of the Administrator such a waiver or refund is
equitable and not contrary to the purpose of this subsection.'' For
additional information regarding tolerance objection fee waivers,
contact James Tompkins, 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: Rm. 239, Crystal Mall #2, 1921 Jefferson Davis Hwy.,
Arlington, VA, (703) 305-5697, tompkins.jim@epa.gov. Requests for
waiver of tolerance objection fees should be sent to James Hollins,
Information Resources and Services Division (7502C), Office of
Pesticide Programs, Environmental Protection Agency, 401 M St., SW.,
Washington, DC 20460.
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.
VII. Public Record and Electronic Submissions
EPA has established a record for this regulation under docket
control number [OPP-300855] (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 119 of the Public Information and Records
Integrity Branch, Information Resources and Services Division (7502C),
Office of Pesticide Programs, Environmental Protection Agency, Crystal
Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA.
Objections and hearing requests may be sent by e-mail directly to
EPA at:
opp-docket@epa.gov.
E-mailed objections and hearing requests must be submitted as an
ASCII file avoiding the use of special characters and any form of
encryption.
The official record for this regulation, as well as the public
version, as described in this unit 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 record which
will also include all comments submitted directly in writing. The
official record is the paper record maintained at the Virginia address
in ``ADDRESSES'' at the beginning of this document.
VIII. Regulatory Assessment Requirements
A. Certain Acts and Executive Orders
This final rule establishes 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). 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 tolerances and exemptions that are established
on the basis of a petition 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 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.
B. Executive Order 12875
Under Executive Order 12875, entitled Enhancing the
Intergovernmental Partnership (58 FR 58093, October 28, 1993), EPA may
not issue a regulation that is not required by statute and that creates
a mandate upon a State, local or tribal government, unless the Federal
government provides the funds necessary to pay the direct compliance
costs incurred by those governments. If the mandate is unfunded, EPA
must provide to OMB a description of the extent of EPA's prior
consultation with representatives of affected State, local, and tribal
governments, the nature of their concerns, copies of any written
communications from the governments, and a statement supporting the
need to issue the regulation. In addition, Executive Order 12875
requires EPA to develop an effective process permitting elected
officials and other representatives of State, local, and tribal
governments ``to provide meaningful and timely input in the development
of
[[Page 28384]]
regulatory proposals containing significant unfunded mandates.''
Today's rule does not create an unfunded Federal mandate on State,
local, or tribal governments. The rule does not impose any enforceable
duties on these entities. Accordingly, the requirements of section 1(a)
of Executive Order 12875 do not apply to this rule.
C. Executive Order 13084
Under Executive Order 13084, entitled Consultation and Coordination
with Indian Tribal Governments (63 FR 27655, May 19, 1998), EPA may not
issue a regulation that is not required by statute, that significantly
or uniquely affects the communities of Indian tribal governments, and
that imposes substantial direct compliance costs on those communities,
unless the Federal government provides the funds necessary to pay the
direct compliance costs incurred by the tribal governments. If the
mandate is unfunded, EPA must provide OMB, in a separately identified
section of the preamble to the rule, a description of the extent of
EPA's prior consultation with representatives of affected tribal
governments, a summary of the nature of their concerns, and a statement
supporting the need to issue the regulation. In addition, Executive
Order 13084 requires EPA to develop an effective process permitting
elected officials and other representatives of Indian tribal
governments ``to provide meaningful and timely input in the development
of regulatory policies on matters that significantly or uniquely affect
their communities.''
Today's rule does not significantly or uniquely affect the
communities of Indian tribal governments. This action does not involve
or impose any requirements that affect Indian tribes. Accordingly, the
requirements of section 3(b) of Executive Order 13084 do not apply to
this rule.
IX. Submission to Congress and the Comptroller General
The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the Agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and the Comptroller General of the United
States. EPA will submit 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 United States prior
to publication of the rule in the Federal Register. This rule 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 12, 1999.
James Jones,
Director, Registration Division, 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:
Authority: 21 U.S.C. 321(q), 346a and 371.
2. In Sec. 180.474, by alphabetically adding the following
commodity ``garlic'' to the table in paragraph (b) to read as follows:
Sec. 180.474 Tebuconazole; tolerances for residues.
* * * * *
(b) * * *
------------------------------------------------------------------------
Parts Expiration/
Commodity per Revocation
million Date
------------------------------------------------------------------------
* * * * *
Garlic............................................ 0.1 6/30/00
* * * * *
------------------------------------------------------------------------
* * * * *
[FR Doc. 99-12935 Filed 5-25-99; 8:45 am]
BILLING CODE 6560-50-F
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