Fenbuconazole; Pesticide Tolerances for Emergency Exemptions
[Federal Register: June 10, 1998 (Volume 63, Number 111)]
[Rules and Regulations]
[Page 31633-31640]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr10jn98-26]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300662; FRL 5791-5]
RIN 2070-AB78
Fenbuconazole; 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 fenbuconazole and its metabolites in or on blueberries.
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
[[Page 31634]]
the pesticide on blueberries in several States. This regulation
establishes a maximum permissible level for residues of fenbuconazole
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 December 31,
1999.
DATES: This regulation is effective June 10, 1998. Objections and
requests for hearings must be received by EPA on or before August 10,
1998.
ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [OPP-300662], 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-300662], 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, CM #2, 1921
Jefferson Davis Hwy., Arlington, VA.
A copy of objections and hearing requests filed with the Hearing
Clerk may also be submitted electronically by sending electronic mail
(e-mail) to: opp-docket@epamail.epa.gov. Copies of objections and
hearing requests must be submitted as an ASCII file avoiding the use of
special characters and any form of encryption. Copies of objections and
hearing requests will also be accepted on disks in WordPerfect 5.1/6.1
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-300662]. 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: Daniel Rosenblatt,
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) 308-9375; e-mail:
rosenblatt.dan@epamail.epa.gov.
SUPPLEMENTARY INFORMATION: EPA, on its own initiative, pursuant to
section 408(e) and (l)(6) of the Federal Food, Drug, and Cosmetic Act
(FFDCA), 21 U.S.C. 346a(e) and (l)(6), is establishing a tolerance for
the fungicide fenbuconazole and its metabolites, in or on blueberries
at 1.0 part per million (ppm). This tolerance will expire and is
revoked on December 31, 1999. 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 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 Fenbuconazole on Blueberries and FFDCA
Tolerances
Mummy berry disease Monilinia vaccinii-corymbosi is a plant disease
which causes a variety of leaf, flower, and fruit damage. Of special
concern for blueberry producers are the blighted flower clusters on
blueberry bushes and mummified fruit that the disease will produce.
Yield loss projections suggest that mummy berry disease may produce
losses of 25-50% of the blueberry crop. In addition, the mummified
fruit will serve as the inoculum for subsequent outbreaks of mummy
berry disease so it is important to gain control over the pest in order
to avert future problem outbreaks.
In past growing seasons, blueberry growers typically used triforine
to control mummy berry disease. However, triforine was voluntarily
canceled by its manufacturer. Now that triforine pesticides have been
canceled, there do not appear to be any registered pesticidal or
cultural measures that growers can use. Therefore, EPA concurs that the
pressures presented by mummy berry disease on blueberry growers
represent an urgent and non-routine situation and has authorized under
FIFRA section 18 the use of fenbuconazole on blueberries to numerous
States.
As part of its assessment of this emergency exemption, EPA assessed
the potential risks presented by residues of fenbuconazole in or on
blueberries. In doing so, EPA considered the new safety standard in
FFDCA section 408(b)(2), and EPA decided that the necessary
[[Page 31635]]
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 December 31, 1999, under FFDCA section 408(l)(5), residues of the
pesticide not in excess of the amounts specified in the tolerance
remaining in or on blueberries 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 fenbuconazole meets EPA's
registration requirements for use on blueberries 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 fenbuconazole by a State for special local needs under
FIFRA section 24(c). Nor does this tolerance serve as the basis for any
States other than those authorized under section 18 to use this
pesticide on this crop without following all provisions of section 18
as identified in 40 CFR part 166. For additional information regarding
the emergency exemption for fenbuconazole, 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
aggregateexposure 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 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
three sources are not typically added because of the very low
probability of this occurring in most cases, and because the other
conservative assumptions built into the assessment assure adequate
protection of public health. However, for cases in which high-end
exposure can reasonably be expected from multiple sources (e.g.
frequent and widespread homeowner use in a specific geographical area),
multiple high-end risks will be aggregated and presented as part of the
comprehensive risk assessment/characterization. Since the toxicological
endpoint considered in this assessment reflects exposure over a period
of at least 7 days, an additional degree of conservatism is built into
the assessment; i.e., the risk assessment nominally covers 1-7 days
exposure, and the toxicological endpoint/NOEL is selected to be
adequate for at least 7 days of exposure. (Toxicity results at lower
levels when the dosing duration is increased.)
[[Page 31636]]
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 (females 13
years and older) 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
fenbuconazole and to make a determination on aggregate exposure,
consistent with section 408(b)(2), for a time-limited tolerance for
residues of fenbuconazole and its metabolites on blueberries at 1.0
ppm. EPA's assessment of the dietary exposures and risks associated
with establishing the tolerance follows.
A. Toxicological Profile
EPA has evaluated the available toxicity data and considered its
validity, completeness, and reliability as well as the relationship of
the results of the studies to human risk. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and
children. The nature of the toxic effects caused by fenbuconazole are
discussed below.
1. Acute toxicity. For the purposes of the acute dietary risk
assessment, EPA assessments are based on an acute RfD of 0.3
milligrams/kilogram/day (mg/kg/day). This figure is derived from
developmental toxicity data from laboratory animals where the NOEL was
determined to be 30 mg/kg/day. The observed effect was a decrease in
the number of live fetuses at the Lowest Effect Level (LEL) of 75 mg/
kg/day and an uncertainty factor of 100. EPA determined that an
additional safety factor of 3x for the protection of infants and
children was appropriate. Therefore, the FQPA acute allowable risk is
0.1 mg/kg/day.
2. Short - and intermediate - term toxicity. No dermal or systemic
toxicity endpoints were identified for this exposure duration.
Therefore, a risk assessment is not needed.
3. Chronic toxicity. EPA has established the RfD for fenbuconazole
at 0.03 mg/kg/day. This RfD is based on a chronic toxicity study in the
rat with a NOEL of 3.03/4.02 in males/females. The NOEL is based on
decreased body weight gains (females), hepatocellular enlargement and
vaculation (females), increases in thyroid weight (both sexes) and
histopathological lesions in the thyroid glands (males), at the LEL of
30.62/43.04 mg/kg/day in males/females. For the population subgroup of
infants and children an uncertainty factor of 300 was used. The FQPA
chronic allowable risk is 0.01 mg/kg/day for infants, children, and
females 13 years and older.
4. Carcinogenicity. Using its Guidelines for Carcinogen Risk
Assessment, EPA has classified fenbuconazole as a Group C (possible
human carcinogen) chemical. EPA believes it is appropriate to use the
Q<INF>1</INF><SUP>*</SUP> approach of 3.59 x 10<SUP>-3</SUP> (mg/kg/
day)<SUP>-1</SUP>.
B. Exposures and Risks
1. From food and feed uses. Tolerances have been established (40
CFR 180.480) for the use of fenbuconazole and its metabolites, in or on
a variety of raw agricultural commodities. Time-limited tolerances have
been established for residues of fenbuconazole, alpha-2-(4-
chlorophenyl)-ethyl-alpha-phenyl-3-(1H-1,2,4-triazole)-1-
propanenitrile] and its metabolites, cis-5-(4-chlorophenyl)dihydro-3-
phenyl-3-(1H 1,2,4-triazole-1-ylmethyl-2-3H-furanone, expressed as
fenbuconazole in or on commodities ranging from 0.1 ppm in pecans to
2.0 ppm in the stone fruit crop group. Risk assessments were conducted
by EPA to assess dietary exposures and risks from fenbuconazole 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 one day or single exposure. In conducting an acute dietary risk
assessment for fenbuconazole, EPA has made conservative assumptions
which result in an overestimate of human dietary exposure. The acute
dietary (food only) risk assessment used TMRC. The resulting high-end
exposure estimate is 0.015 mg/kg/day. This exposure level utilizes 15%
of the dietary (food only) FQPA acute allowable risk for females 13+
years. Refinement using anticipated residue values and percent crop-
treated data in conjunction with Monte Carlo analysis would result in
lower acute dietary exposure estimates.
ii. Chronic exposure and risk. The chronic dietary risk assessment
is partially refined. Tolerance level residues were assumed for all
commodities, including stone fruits. Percent crop treated data were
used for
[[Page 31637]]
stone fruits only and 100% crop-treated data were used for all other
commodities. The existing tolerances for fenbuconazole plus exposures
connected with the section 18 on blueberries result in an anticipated
residue contribution (ARC) that is equivalent to 3% of the RfD for non-
nursing infants (<1 year old), the highest exposed subpopulation.
2. From drinking water. There are no established Maximum
Contaminant Level for residues of fenbuconazole in drinking water and
no health advisory levels for fenbuconazole in drinking water have been
established.
Fenbuconazole is moderately persistent and slightly mobile to
immobile in soil. Because of its adsorption to soil, the potential for
fenbuconazole to leach to ground water appears to be slight. However,
the potential to contaminate ground water may be greater at vulnerable
sites, where soils are low in organic matter and where ground water is
relatively close to the surface. The long half-lives of aerobic soil
and terrestrial field dissipation indicate that when fenbuconazole is
applied over multiple growing seasons, soil residue accumulation may
result. These residues may be available for rotational crop uptake or
may be transported with sediments during runoff events.
For the purposes of EPA's water screening assessments, it is
assumed that adult males weigh 70 kg, adult females 60 kg, and children
10 kg. Average consumption is assumed to be 2 liters/day for adults and
1 liter/day for children.
EPA performed a ground water assessment with its ground water
screening tool to establish an estimated environmental concentration
(EEC). The Tier I estimate projected that the concentration of
fenbuconazole in drinking water from ground water sources is not likely
to exceed an acute and chronic EEC of 0.019 <greek-m>g/l for ground and
aerial applications.
A Tier I drinking water assessment of fenbuconazole was also
conducted for surface water. The EECs are generated for high exposure
agricultural scenarios and correspond to a stagnant pond with no outlet
that receives pesticide loading from an adjacent 100% cropped, 100%
treated field. As such, these computer generated EECs represent
conservative screening levels for ponds and lakes and are thought to
represent an overestimate of the actual EEC. The peak EEC projection
for surface water involved aerial applications. The acute peak EEC was
4.27 <greek-m>g/l. The chronic 56-day EEC was 2.29 <greek-m>g/l.
Because the surface water EECs appear to be higher, EPA used these
worst case calculations in its dietary risk assessment.
i. Acute exposure and risk. EPA calculated the acute risks from
drinking water for fenbuconazole based on dietary (food) exposure and
the default assumptions mentioned above. To calculate the acute
drinking water level of concern (DWLOC), the acute dietary food
exposure estimate is subtracted from the acute RfD.
The calculations were based on the following: the acute RfD for
fenbuconazole is 0.3 mg/kg/day; the FQPA acute allowable risk is 0.1
mg/kg/day based on an uncertainty factor of 3. If the acute food
exposure estimate (0.015 mg/kg/day) is subtracted from the FQPA acute
allowable risk (0.1 mg/kg/day) the result is the maximum acute water
exposure which is 0.085 mg/kg/day or 2,600 parts per billion (ppb).
The peak EEC (acute) value is 4.27 ppb, based on aerial application
of fenbuconazole. This figure is significantly lower that the DWLOC of
2,600 ppb. Therefore, EPA concludes with reasonable certainty that the
acute exposure to fenbuconazole in drinking water is less than the
level of concern.
ii. Chronic exposure and risk. To calculate the chronic DWLOC, the
chronic dietary food exposure is subtracted from the RfD. Chronic
DWLOCs were calculated for various subpopulations ranging from 1,050
ppb for the U.S. population to 92 ppb for infants and children (non-
nursing < 1 year). The computer model suggested that the chronic EEC
for fenbuconazole is 2.29 ppb for aerial applications of the pesticide.
Since the EEC is less than the DWLOC, EPA concludes that there is
reasonable certainty that chronic exposure is less than the level of
concern.
EPA calculated the cancer risk associated with fenbuconazole and
drinking water. To calculate the DWLOC for cancer, the chronic dietary
food exposure was subtracted from the negligible risk standard (1 x
10<SUP>-6</SUP>) divided by the Q<INF>1</INF><SUP>*</SUP> (0.00359 mg/
kg/day). EPA's drinking water level of concern from cancer is 5.4 ppb
for the U.S. population. This compares to the level of 2.29 ppb from
the conservative computer model EPA used to estimate exposures. Since
the DWLOC is higher than the calculated EEC of 2.29 ppb, EPA concludes
with reasonable certainty that exposure to fenbuconazole in drinking
water does not pose a level of concern with respect to cancer risks.
3. From non-dietary exposure. Fenbuconazole is not currently
registered for any residential or non-food use sites. Therefore, a
discussion of the toxicity endpoints for non-dietary exposure and a
risk assessment for these uses is not germane to this review.
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 fenbuconazole has a common mechanism of toxicity with other
[[Page 31638]]
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,
fenbuconazole 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 fenbuconazole has a common mechanism of
toxicity with other substances.
C. Aggregate Risks and Determination of Safety for U.S. Population
1. Acute risk. For the population subgroup of concern, females 13
years and older, EPA used the TMRC approach and calculated that
exposure would utilize 15% of the RfD. EPA generally has no concerns
for exposures below 100% of the acute RfD. In addition, for acute
exposures associated with drinking water, EPA has concluded that the
level of concern is 2,600 ppb. The EEC value is 4.27 ppb. This leads
EPA to conclude that acute exposure to fenbuconazole does not pose a
level of concern.
2. Chronic risk. Using ARC exposure assumptions, EPA has concluded
that aggregate exposure to fenbuconazole from food will utilize less
than 1% of the RfD for the U.S. population. The major identifiable
subgroup with the highest aggregate exposure is non-nursing infants
where 3% of the RfD is utilized. A full discussion of the risks
associated with exposure to infants and children is presented 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. EPA's level of concern from chronic exposure to drinking
water is 1,050 ppb for the U.S. population. The EEC for aerial
application is projected to be 2.29 ppb. Therefore, EPA concludes that
there is a reasonable certainty that no harm will result from aggregate
exposure to fenbuconazole residues.
3. Short- and intermediate-term risk. Short- and intermediate-term
endpoints were not identified for fenbuconazole. Therefore, an
aggregate risk assessment was not conducted for these endpoints.
Furthermore, fenbuconazole has no residential uses.
D. Aggregate Cancer Risk for U.S. Population
Fenbuconazole has been classified as a Group C Carcinogen with a
Q<INF>1</INF><SUP>*</SUP> of 3.59 x 10<SUP>-3</SUP> (0.00359 mg/kg/
day). The Q<SUP>*</SUP> approach was used for risk assessments
involving carcinogenic effects. Using partially refined exposure
estimates, the cancer risk estimate for the U.S. population is 3.25 x
10<SUP>-7</SUP>. For exposures connected with drinking water, EPA's
level of concern is 5.4 ppb. EPA projects that the EEC for
fenbuconazole is 2.29 ppb. Therefore, EPA concludes with reasonable
certainty that exposure to fenbuconazole does not exceed the level of
concern for cancer risks.
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 fenbuconazole, 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 database unless EPA determines that a different
margin of safety will be safe for infants and children. Margins of
safety are incorporated into EPA risk assessments either directly
through use of a MOE analysis or through using uncertainty (safety)
factors in calculating a dose level that poses no appreciable risk to
humans. EPA believes that reliable data support using the standard MOE
and uncertainty factor (usually 100 for combined inter- and intra-
species variability) and not the additional tenfold MOE/uncertainty
factor when EPA has a complete data base under existing guidelines and
when the severity of the effect in infants or children or the potency
or unusual toxic properties of a compound do not raise concerns
regarding the adequacy of the standard MOE/safety factor.
ii. Developmental toxicity studies. In the developmental toxicity
study in rats, the maternal (systemic) NOEL was 30 mg/kg/day, based on
decreases in body weight and body weight gain at the LOEL of 75 mg/kg/
day. The developmental (fetal) NOEL was 30 mg/kg/day, based on an
increase in post implantation loss and a significant decrease in the
number of live fetuses per dam at the LOEL of 75 mg/kg/day. In the
developmental toxicity study in rabbits, the maternal (systemic) NOEL
was 10 mg/kg/day, based on decreased body weight gain at the LOEL of 30
mg/kg/day. The developmental (pup) NOEL was 30 mg/kg/day, based on
increased resorptions at the LOEL of 60 mg/kg/day.
iii. Reproductive toxicity study. In the 2-generation reproductive
study in rats, the paternal (systemic) NOEL was 4 mg/kg/day, based on
decreased body weight and food consumption, increased number of dams
not delivering viable or delivering nonviable offspring, and increases
in adrenal and thyroid weights at the LOEL of 40 mg/kg/day. The
reproductive (pup) NOEL was 40 mg/kg/day, the highest dose tested
(HDT).
iv. Pre- and post-natal sensitivity. The toxicological data base
for evaluating pre-and post-natal toxicity for fenbuconazole is
complete with respect to EPA's current data requirements. Based on the
developmental and reproductive toxicity studies there is not adequate
evidence to completely remove the FQPA 10x factor. There is some
evidence suggestive of increased susceptibility in developing
offspring. An increase in post implantation loss and a significant
decrease in the number of live fetuses per dam in rats in the presence
of effects on maternal weight gain may be indicative of increased
susceptibility in the fetus. However, the increased incidence does not
appear to be very great at 75 mg/kg/day for either effect. Similarly,
in rabbits there are reported resorptions at 60 mg/kg/day and effects
on maternal weight gain at 30 mg/kg/day. Therefore, EPA determined that
the 10x factor required by FQPA for protection of infants and children
from exposure to fenbuconazole should be reduced to 3x.
The retention of the 3x factor for this risk assessment does not
result in exposure values which exceed EPA's level of concern. This
action should not pose an unacceptable aggregate risk to infants and
children.
2. Acute risk. Toxicological effects relevant to infants and
children that could be attributed to a single exposure (dose) were not
observed in oral toxicity studies including the developmental toxicity
studies in rats and rabbits. A dose and endpoint was not identified.
Therefore, an aggregate risk assessment is not required for this
subpopulation.
3. Chronic risk. Using ARC exposure assumptions, EPA has concluded
that aggregate exposure to fenbuconazole from food will utilize 3% of
the RfD for non-nursing infants less than 1 year old to less than 1%
for children 1-6 years old. EPA generally has no concern for exposures
below 100% of the RfD
[[Page 31639]]
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. EPA's level of concern for chronic exposure to infants
and children through drinking water is 92 ppb. EPA's water exposure
model suggests that aerial application could result in an EEC of 2.29
ppb. Therefore, EPA concludes that there is a reasonable certainty that
no harm will result to infants and children from aggregate exposure to
fenbuconazole residues.
V. Other Considerations
A. Metabolism In Plants and Animals
The nature of the residue of fenbuconazole for this action is
adequately understood. The residue of concern is fenbuconazole (alpha-
[2-4-chlorophenyl)-ethyl]alpha-phenyl-3-(1H-1,2,4-triazole)-1-
propanenitrile] and its metabolites, cis-5-(4-chlorophenyl)dihydro-3-
phenyl-3-(1H-1,2,4-triazole-1-ylmethyl)-2-3H-furanoneandtrans-5-(4-
chlorophenyl)dihydro-3-phenyl-3-(1H-1,2,4-triazole-1-ylmethyl)-2-3H-
furanone, expressed as fenbuconazole as specified in 40 CFR 180.480.
No livestock feed items are associated with this request. Thus, the
nature of the residue in livestock is not of concern.
B. Analytical Enforcement Methodology
Analytical methodology is available to enforce the tolerances
forfenbuconazole.
C. Magnitude of Residues
Residues of fenbuconazole and its regulated metabolites are not
expected to exceed 1.0 ppm in/on blueberries. Secondary residues are
not expected as no livestock feed items are associated with this use.
D. International Residue Limits
There are no CODEX, Canadian, or Mexican maximum residue limits
(MRLs) for fenbuconazole on blueberries.
E. Rotational Crop Restrictions
Blueberries are not rotated. Rotational crop restrictions are not
germane to this action.
VI. Conclusion
Therefore, the tolerance is established for residues of
fenbuconazole (alpha-[2-4-chlorophenyl)-ethyl]alpha-phenyl-3-(1H-1,2,4-
triazole)-1-propanenitrile] and its metabolites, cis-5-(4-
chlorophenyl)-dihydro-3-phenyl-3-(1H-1,2,4-triazole-1-ylmethyl)-2-3H-
furanone and trans-5-(4-chlorophenyl)dihydro-3-phenyl-3-(1H 1,2,4-
triazole-1-ylmethyl-2-3H-furanone, expressed as fenbuconazole in
blueberries at 1.0 ppm.
VII. Objections and Hearing Requests
The new FFDCA section 408(g) provides essentially the same process
for persons to ``object'' to a tolerance regulation issued by EPA under
new section 408(e) and (l)(6) as was provided in the old section 408
and in section 409. However, the period for filing objections is 60
days, rather than 30 days. EPA currently has procedural regulations
which govern the submission of objections and hearing requests. These
regulations will require some modification to reflect the new law.
However, until those modifications can be made, EPA will continue to
use those procedural regulations with appropriate adjustments to
reflect the new law.
Any person may, by August 10, 1998, 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 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 Record and Electronic Submissions
EPA has established a record for this rulemaking under docket
control number [OPP-300662] (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.
Electronic comments may be sent directly to EPA at:
opp-docket@epamail.epa.gov.
Electronic comments must be submitted as an ASCII file avoiding the
use of special characters and any form of encryption.
The official record for this rulemaking, as well as the public
version, as described above will be kept in paper form. Accordingly,
EPA will transfer any copies of objections and hearing requests
received electronically into printed, paper form as they are received
and will place the paper copies in the official rulemaking record which
will also include all comments submitted directly in writing. The
official rulemaking record is the paper record maintained at the
Virginia address in ``ADDRESSES'' at the beginning of this document.
IX. Regulatory Assessment Requirements
This final rule establishes a tolerance under FFDCA section 408(d)
in response to a petition submitted to the Agency. 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
[[Page 31640]]
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 Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.
Dated: May 20, 1998.
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. 346a and 371.
2. Section 180.480 is amended by adding a heading to paragraph (a);
by designating the text in paragraph (a) as paragraph (a)(1); by
redesignating paragraph (b) as paragraph (a)(2) and amending it to
revise the phrase ``paragraph (a) of this section'' to read ``paragraph
(a)(1) of this section''; by adding a new paragraph (b); and by adding
and reserving with headings paragraphs (c) and (d) to read as follows:
Sec. 180.480 Fenbuconazole; tolerances for residues.
(a) General. (1) * * *
(2) * * *
(b) Section 18 emergency exemptions. A time-limited tolerance is
established for fenbuconazole (alpha-[2-4-chlorophenyl)-ethyl]alpha-
phenyl-3-(1H-1,2,4-triazole)-1-propanenitrile] and its metabolites,
cis-5-(4-chlorophenyl)-dihydro-3-phenyl-3-(1H-1,2,4-triazole-1-
ylmethyl)-2-3H-furanone and trans-5-(4-chlorophenyl)dihydro-3-phenyl-3-
(1H 1,2,4-triazole-1-ylmethyl-2-3H-furanone, expressed as fenbuconazole
in or on blueberries in connection with use of the pesticide under a
section 18 exemption granted by EPA. The time-limited tolerance will
expire on the date specified in the following table.
------------------------------------------------------------------------
Expiration/
Commodity Parts per million revocation date
------------------------------------------------------------------------
Blueberries..................... 1.0 12/31/99
------------------------------------------------------------------------
(c) Tolerances with regional registrations. [Reserved]
(d) Indirect or inadvertent residues. [Reserved]
[FR Doc. 98-15173 Filed 6-9-98; 8:45 am]
BILLING CODE 6560-50-F
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