[Federal Register Volume 63, Number 92 (Wednesday, May 13, 1998)]
[Rules and Regulations]
[Pages 26473-26481]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-12639]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300661; FRL-5790-8]
RIN 2070-AB78
Bromoxynil; Pesticide Tolerance
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes tolerances for bromoxynil and DBHA
in or on cotton. In addition, this regulation establishes tolerances
for bromoxynil and DBHA in or on meat, meat by products, and fat of
cattle, hogs, horses, goats, and sheep. Further, this regulation
establishes tolerances for bromoxynil and DBHA in milk, eggs, and
poultry meat, meat by-products, and fat. Rhone-Poulenc Ag Company
requested the tolerances for cotton under the Federal Food, Drug, and
Cosmetic Act, as amended by the Food Quality Protection Act of 1996
(Pub. L. 104-170).
DATES: This regulation is effective May 13, 1998. Objections and
requests for hearings must be received by EPA on or before July 13,
1998.
ADDRESSES: Written objections and hearing requests, identified by the
docket control number, [OPP-300661], 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-300661], 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: [email protected]. 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-300661]. 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: Jim 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: Crystal Mall #2, 1921
Jefferson Davis Hwy., Arlington, VA, 703-305-5697, e-mail:
[email protected].
SUPPLEMENTARY INFORMATION: In the Federal Register of November 26, 1997
(62 FR 63170) (FRL-5755-6), EPA, issued a notice pursuant to section
408 of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C.
346a(e) announcing the filing of a pesticide petition (PP) 3F4233 for
tolerance by Rhone-Poulenc Ag Company. This notice included a summary
of the petition prepared by Rhone-Poulenc Ag Company, the registrant.
Comments in response to the notice of filing were received from public
interest groups, individual concerned citizens, agricultural extension
agents, representatives of State agencies, individual growers, and
industry groups. The issues raised were the same issues raised in
response to the proposed rule (May 2, 1997, 62 FR 24065) (FRL-5617-5)
for the bromoxynil tolerance that expired on January 1, 1998. Many of
the comments are addressed in this document. Responses to other
significant comments are presented in Unit III. of the final rule for
last year's tolerance (June 18, 1997, 62 FR 33019) (FRL-5724-9) or in a
Response to Comments document that has been included in the docket for
that action.
The petition requested that 40 CFR 180.324 be amended by
establishing tolerances for residues of the herbicide bromoxynil plus
its metabolite DBHA (3,5-dibromo-4-hydroxybenzoic acid) resulting from
the application of octanoic and heptanoic acid esters of bromoxynil to
cotton: undelinted cottonseed at 7 parts per million (ppm), cotton gin
byproducts at 50 ppm, and cotton hulls at 21 ppm. (Active ingredient
codes are 35302 for the octanoic acid ester, and 128920 for the
heptanoic acid ester. CAS Reg. Nos. are
[[Page 26474]]
1689-99-2 for the octanoic acid ester, and 56634-95-8 for the heptanoic
acid ester.) The tolerances established in this final rule differ from
these tolerances proposed by the registrant as the result of the review
of residue data for bromoxynil and DBHA in cotton commodities submitted
by the registrant after the petition was filed. In addition, the
petition requested that the maximum allowable cotton acreage that can
be treated annually with bromoxynil be increased from 400,000 acres to
1.3 million acres.
In the Federal Register of May 24, 1995 (60 FR 27414) (FRL-4953-9),
EPA established a time-limited tolerance under section 408 of the
FFDCA, 21 U.S.C. 346a, for residues of the herbicide bromoxynil, (3,5-
dibromo-4- hydroxybenzonitrile) on cottonseed. This tolerance expired
on April 1, 1997. The tolerance was established in response to a
petition filed by the Rhone-Poulenc AG Company, P.O. Box 12014, 2 T.W.
Alexander Drive, Research Triangle Park, NC 27709.
In the Federal Register of May 2, 1997 (62 FR 24065), EPA issued a
proposed rule for establishment of tolerances on cotton commodities and
poultry, eggs, and milk, and revision of tolerances on other livestock.
In the Federal Register of June 18, 1997 (62 FR 33019), EPA issued a
final rule for establishment of tolerances on cotton commodities and
poultry, eggs, and milk, and revision of tolerances on other livestock.
The tolerances for the cotton commodities expired on January 1, 1998.
I. Risk Assessment and Statutory Findings
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. . . .''
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. First, EPA determines the
toxicity of pesticides based primarily on toxicological studies using
laboratory animals. These studies address many adverse health effects,
including (but not limited to) reproductive effects, developmental
toxicity, toxicity to the nervous system, and carcinogenicity. Second,
EPA examines exposure to the pesticide through the diet (e.g., food and
drinking water) and through exposures that occur as a result of
pesticide use in residential settings.
A. Toxicity
1. Threshold and non-threshold effects. For many animal studies, a
dose response relationship can be determined, which provides a dose
that causes adverse effects (threshold effects) and doses causing no
observed effects (the ``no-observed effect level'' or ``NOEL'').
Once a study has been evaluated and the observed effects have been
determined to be threshold effects, EPA generally divides the NOEL from
the study with the lowest NOEL by an uncertainty factor (usually 100 or
more) to determine the Reference Dose (RfD). The RfD is a level at or
below which daily aggregate exposure over a lifetime will not pose
appreciable risks to human health. An uncertainty factor (sometimes
called a ``safety factor'') of 100 is commonly used since it is assumed
that people may be up to 10 times more sensitive to pesticides than the
test animals, and that one person or subgroup of the population (such
as infants and children) could be up to 10 times more sensitive to a
pesticide than another. In addition, EPA assesses the potential risks
to infants and children based on the weight of the evidence of the
toxicology studies and determines whether an additional uncertainty
factor is warranted. Thus, an aggregate daily exposure to a pesticide
residue at or below the RfD (expressed as 100% or less of the RfD) is
generally considered acceptable by EPA. EPA generally uses 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 the pesticide residues from treated food and
contaminated drinking water is 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 the Food
Quality Protection Act of 1996 (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
[[Page 26475]]
can reasonably be expected from multiple sources (e.g. frequent and
widespread homeowner use in a specific geographical area), multiple
high-end risks will be aggregated and presented as part of the
comprehensive risk assessment/characterization. Since the toxicological
endpoint considered in this assessment reflects exposure over a period
of at least 7 days, an additional degree of conservatism is built into
the assessment; i.e., the risk assessment nominally covers 1-7 days
exposure, and the toxicological endpoint/NOEL is selected to be
adequate for at least 7 days of exposure. (Toxicity results at lower
levels when the dosing duration is increased.)
Intermediate-term risk results from exposure for 7 days to several
months. This assessment is handled in a manner similar to the short-
term risk assessment.
Chronic risk assessment describes risk which could result from
several months to a lifetime of exposure. For this assessment, risks
are aggregated considering average exposure from all sources for
representative population subgroups including infants and children.
B. Aggregate Exposure
In examining aggregate exposure, FFDCA section 408 requires that
EPA take into account available and reliable information concerning
exposure from the pesticide residue in the food in question, residues
in other foods for which there are tolerances, residues in groundwater
or surface water that is consumed as drinking water, and other non-
occupational exposures through pesticide use in gardens, lawns, or
buildings (residential and other indoor uses). Dietary exposure to
residues of a pesticide in a food commodity are estimated by
multiplying the average daily consumption of the food forms of that
commodity by the tolerance level or the anticipated pesticide residue
level. The Theoretical Maximum Residue Contribution (TMRC) is an
estimate of the level of residues consumed daily if each food item
contained pesticide residues equal to the tolerance. In evaluating food
exposures, EPA takes into account varying consumption patterns of major
identifiable subgroups of consumers, including infants and children.
The TMRC is a ``worst case'' estimate since it is based on the
assumptions that food contains pesticide residues at the tolerance
level and that 100% of the crop is treated by pesticides that have
established tolerances. If the TMRC exceeds the RfD or poses a lifetime
cancer risk that is greater than approximately one in a million, EPA
attempts to derive a more accurate exposure estimate for the pesticide
by evaluating additional types of information (anticipated residue data
and/or percent of crop treated data) which show, generally, that
pesticide residues in most foods when they are eaten are well below
established tolerances.
II. 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
bromoxynil and to make a determination on aggregate exposure,
consistent with section 408(b)(2), for tolerances for bromoxynil and
DBHA on undelinted cottonseed at 1.5 ppm; cotton gin byproducts at 7.0
ppm; and cotton hulls at 5.0 ppm; in or on cattle, hogs, horses, goats,
and sheep at 0.5 ppm in meat, 3.5 ppm in meat by-products (mbyp), and
1.0 ppm in fat; at 0.1 ppm in milk; at 0.05 ppm in eggs; at 0.05 ppm in
poultry meat and fat; and at 0.3 ppm in poultry mbyp. EPA's assessment
of the dietary exposures and risks associated with establishing the
tolerances follows.
A. Toxicological Profile
EPA has evaluated the available toxicity data and considered its
validity, completeness, and reliability as well as the relationship of
the results of the studies to human risk. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and
children. The nature of the toxic effects caused by bromoxynil are
discussed in the proposed rule (May 2, 1997, 62 FR 24065).
B. Toxicological Endpoints
The toxicological endpoints for bromoxynil are discussed in Unit
IV. ``Dose Response Assessment'' of the proposed rule for last year's
tolerance (May 2, 1997, 62 FR 24065).
C. Exposures and Risks
1. From food and feed uses. Tolerances have been established (40
CFR 180.324) for the residues of bromoxynil, in or on a variety of raw
agricultural commodities. Tolerances for the residues of bromoxynil,
resulting from the application of octanoic and heptanoic acid esters of
bromoxynil to cotton, have been established in or on cattle, hogs,
horses, goats, and sheep at 0.5 ppm in meat, 3.0 ppm in mbyp, and 1.0
ppm in fat. Tolerances for residues of bromoxynil, resulting from the
application of octanoic and heptanoic acid esters of bromoxynil to
cotton have been established at 0.1 ppm in milk; and at 0.05 ppm in
eggs; at 0.05 ppm in poultry meat, mbyp, and fat. Risk assessments were
conducted by EPA to assess dietary exposures and risks from bromoxynil
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. A revised acute dietary risk
assessment was conducted for bromoxynil. This revised acute dietary
assessment differs from the assessment used for last year's tolerance
as follows: (a) The results of a new cotton residue study were used to
determine anticipated bromoxynil residues; (b) a probabilistic
assessment submitted by the registrant was used. The acute assessment
used a NOEL of 4 milligram/kilograms body weight/day (mg/kg bw/day)
based on developmental effects with the population subgroup of concern
being females 13 years old and a NOEL of 8 mg/kg bw/day
based on systemic effects for all populations except females
13 years old. The acute analysis estimates the distribution
of single-day exposures for the overall U.S. population and certain
subgroups. The MOE is a measure of how closely the exposure comes to
the NOEL and is calculated as a ratio of the NOEL to the exposure. The
calculated MOE for acute risk of bromoxynil for the general U. S.
Population is >58,000 and for females 13 years old is
>24,000. For the most exposed subgroups, the calculated MOE for acute
risk of bromoxynil is >32,000 for non-nursing infants, >36,000 for all
infants, and >35,000 for children 1-6 years old. These figures are
above the required MOE of 1,000 for females 13 years old and
100 for the general population and all other population subgroups,
indicating that the potential for an adverse effect from a single day
exposure is unlikely. The level of concern for the general U.S.
population and all population subgroups except for females
13 years is based on interspecies extrapolation (10x) and
intraspecies variability (10x). For females 13 years, an
added factor of 10x is used pursuant to section 408(b)(2)(C) (See Unit
II.E.b. of this document).
ii. Chronic exposure and risk. For chronic exposure to bromoxynil,
the reference dose (0.015 mg/kg/day) is based upon a NOEL/LOEL of 1.5
mg/kg/day, from a 1-year canine study, with additional uncertainty
factors applied
[[Page 26476]]
for intra- (10x) and interspecies (10x) variability.
A DRES chronic exposure analysis was conducted using anticipated
residue levels for all registered commodities and livestock, and
percent crop treated information to estimate dietary exposure for the
general population and several population subgroups. The chronic
analysis showed that for chronic effects other than cancer, for all
population subgroups, less than 1% of the reference dose was consumed.
When EPA establishes, modifies, or leaves in effect a tolerance,
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 five years after the tolerance is established,
modified, or left in effect, demonstrating that the levels in food are
not above the levels anticipated. 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 five 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: (a) 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; (b) that the exposure estimate does not underestimate exposure
for any significant subpopulation group; and (c) 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 percent crop treated as required by the section
408(b)(2)(F), EPA may require registrants to submit data on percent
crop treated.
The Agency used percent crop treated (PCT) information as follows.
A routine chronic dietary exposure analysis for bromoxynil was based on
10% of the cotton crop treated, 10% of all cereal grain crops (wheat,
corn, oats, barley, rye, sorghum) treated, 62% of the onion crop
treated, 100% of the garlic crop treated, and 71% of peppermint and
spearmint crop treated. PCT of 10% for cotton was based on the
petitioner's request that the Agency permit up to 1.3 million acres of
cotton to be treated annually with bromoxynil, which amounts to 10% of
the cotton crop grown in the U.S. The registration of bromoxynil will
restrict treatment of bromoxynil on cotton to no more than 1.3 million
acres during 1998.
The Agency believes that the three conditions listed above have
been met. With respect to (a), EPA finds that the PCT information
described above for bromoxynil used on cotton is reliable and has a
valid basis. The registration of bromoxynil will restrict treatment of
bromoxynil on cotton to no more than 1.3 million acres during 1998.
Before the petitioner can increase the treatment of greater than 1.3
million acres of cotton per year, permission from the Agency must be
obtained. For crops other than cotton, the Agency has utilized the
latest statistical data from RFF (Resources For The Future), Doane, and
the U.S. Department of Agriculture (USDA), the best available sources
for such information. As to (b) and (c), 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 consumption of food bearing
bromoxynil in a particular area.
The cancer risk from all food sources is 1.5 in a million if 10% of
the cotton is treated. These risk estimates are based on anticipated
residues and percent crop treated information.
2. From drinking water. Based on the chemical characteristics and
monitoring data, bromoxynil residues are not expected to be found in
ground water. For the action last year (June 18, 1997, 62 FR 33019), an
analysis of surface water based on cotton use was conducted using the
PRZM-EXAMS computer model (Pesticide Root Zone Model Version 2.3 plus
Exposure Analysis Modeling System Version 2.94). The maximum or peak
estimated concentration for bromoxynil was 12.3 parts per billion (ppb)
and the maximum estimated long-term mean was 0.24 ppb (based on
modeling using 36 years of weather data). These values represent what
might be expected in a small water body near a cotton field highly
prone to runoff. The maximum peak estimated concentration for
bromoxynil from the model correlates with the highest value detected in
the U.S. Geological Survey (USGS) monitoring data, 12.2 ppb, which has
been corrected for an analytical recovery rate of 50%. For this action,
the Agency has reevaluated the concentrations of bromoxynil in surface
water to be used to assess risk associated with drinking water. EPA
reviewed USGS national monitoring data and determined which of these
sites were likely to have bromoxynil use. To estimate a reasonable high
end exposure, EPA focussed on the calculated time weighted annual mean
concentrations of bromoxynil at each of 11 USGS monitoring sites, which
the EPA views as located in watersheds likely to have bromoxynil use.
(These values were not corrected for the analytical recovery rate of
50%.) These time weighted annual mean concentrations ranged from 0.011
ppb to 0.18 ppb, with 10 out of the 11 sites with time weighted annual
mean concentrations below 0.05 ppb. Six of the 10 sites had time
weighted annual mean concentrations at or below 0.014 ppb. The highest
annual time-weighted mean (0.18 ppb) was located in a relatively small
watershed (approximately 100 square miles) and a relatively small water
body, and the calculated annual mean value at this site was
significantly influenced by the presence of a single high value (the
highest value found in all of the available monitoring data). Based on
this information, EPA believes that 0.05 ppb is a reasonable high end
estimate for purposes of estimating drinking water exposure. However,
EPA is imposing surface water monitoring requirements as a condition of
registration to allow use of more precise estimates in the future.
i. Acute exposure and risk. Acute drinking water exposure was
calculated by multiplying the estimated concentration of bromoxynil in
surface water (12.3 ppb) by the estimated water consumption (2 liters
for adults, 1 liter for children) and then dividing by body weight (70
kg for males, 60 kg for females, and 10 kg for children). Acute
drinking water exposure is calculated to be 3.5 x 10-4 mg/
kg/day for adult males and females, and 1.2 x 10-4 mg/kg/day
for children. The MOE for drinking water for all three population
subgroups is >10,000.
ii. Chronic exposure and risk. Chronic drinking water risk was
calculated in the same way as acute risk, except that
[[Page 26477]]
the estimated mean concentrations of 0.24 ppb, 0.05 ppb, and 0.01 ppb
were used. At 0.24 ppb, the highest of these concentrations, chronic
drinking water exposure is calculated to be 2 x 10-5 mg/kg/
day for children, 7 x 10-6 mg/kg/day for males, and 8 x
10-6 mg/kg/day for females. All of these exposures are <1%
of the RfD of 0.015 mg/kg/day. The cancer risk (calculated based on a
70-year lifetime) is calculated to be 8 x 10-7 at a chronic
water exposure concentration of 0.24 ppb, 2 x 10-7 at a
concentration of 0.05 ppb, and 3 x 10-8 at a concentration
of 0.01 ppb. The Agency has determined that a concentration of 0.05 ppb
for bromoxynil is a reasonable high end of exposure for bromoxynil in
surface water; therefore, the cancer risk from exposure to bromoxynil
in drinking water is calculated at 2 x 10-7.
EPA believes the estimates of bromoxynil exposure in water derived
from the PRZM-EXAMS model, particularly the estimates pertaining to
chronic exposure, are significantly overstated for several reasons. The
PRZM-EXAMS model was designed to estimate exposure for ecological risk
assessments and thus uses a scenario of a body of water approximating
the size of a 1 hectare (2.5 acres) pond. This tends to overstate
chronic drinking water exposure levels for the following reasons.
First, surface water source drinking water generally comes from bodies
of water that are substantially larger than a 1 hectare (2.5 acres)
pond. Second, the modeled scenario also assumes that essentially the
whole basin receives an application of the pesticide. Yet, in virtually
all cases, basins large enough to support a drinking water facility
will contain a substantial fraction of the area which does not receive
the pesticide. Third, there is often at least some flow (in a river) or
turn over (in a reservoir or lake) of the water so the persistence of
the pesticide near the drinking water facility is usually
overestimated. Fourth, even assuming a reservoir is directly adjacent
to an agricultural field, the agricultural field may not be used to
grow a crop on which the pesticide in question is registered for use.
Fifth, the PRZM-EXAMS modeled scenario does not take into account
reductions in residue-loading due to applications of less than the
maximum application rate or no treatment of the crop at all (percent
crop treated data).
3. From non-dietary exposure. Bromoxynil is currently not
registered for use on any residential non-food sites.
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 bromoxynil 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,
bromoxynil 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 bromoxynil has a common mechanism of toxicity
with other substances.
C. Aggregate Risks and Determination of Safety for U.S. Population
1. Acute risk. The MOE for all dietary sources (food plus water) is
>16,000 for the entire U.S. population, >11,000 for females
13 years old, and >5,000 for children 1-6 years old. These
MOEs are greater than the levels of concern of 1,000 for females
13 years and 100 for all other population groups.
Accordingly, EPA concludes that there is a reasonable certainty that no
harm will result to the general population and major identifiable
population subgroups from aggregate acute exposure to bromoxynil.
2. Chronic risk. Using the exposure assumptions described above,
EPA has concluded that aggregate exposure to bromoxynil from food and
drinking water will utilize <1% of the RfD for the U.S. population. EPA
has also concluded that aggregate exposure to bromoxynil will utilize
<1% of the RfD for the most highly exposed subpopulation, children 1-6
years old (discussed below). EPA generally has no concern for exposures
below 100% of the RfD because the RfD represents the level at or below
which daily aggregate dietary exposure over a lifetime will not pose
appreciable risks to human health. Accordingly, EPA concludes that
there is a reasonable certainty that no harm will result to the general
population and major identifiable population subgroups from aggregate
chronic exposure to bromoxynil.
D. Aggregate Cancer Risk for U.S. Population
The aggregate cancer risk for the U.S. population calculated for
use of bromoxynil is 1.7 x 10-6. EPA believes that a risk
estimate of this level generally represents a negligible risk, as EPA
has traditionally applied that concept. EPA has commonly referred to a
negligible risk as one that is at or below 1 in 1 million (1 x
10-6). Quantitative cancer risk assessment is not a precise
science. There are a significant number of uncertainties in both the
toxicology used to derive the cancer potency of a substance and in the
data used to measure and calculate exposure. Thus, EPA generally does
not attach great significance to numerical estimates that differ by
approximately a factor of 2. Therefore, EPA considers the
[[Page 26478]]
carcinogenic risk from bromoxynil to be negligible within the meaning
of that standard as it has been traditionally applied by EPA.
Accordingly, EPA concludes that there is a reasonable certainty that no
harm will result to the general population and major identifiable
population subgroups from aggregate exposure to bromoxynil. Specific
risks to infants and children other than cancer are discussed below.
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 bromoxynil, EPA considered all available
developmental and reproductive toxicity data. A total of 12
developmental and 3 reproductive toxicity studies were available for
review. These include oral prenatal developmental toxicity studies
(four in rats, two in rabbits, and one in mice with the phenol; one in
rats with the octanoate), dermal prenatal developmental toxicity
studies (one each in rats and rabbits with both the phenol and the
octanoate), and dietary two-generation reproduction studies in rats
(two with the phenol; one with the octanoate). The developmental
toxicity studies are designed to evaluate adverse effects on the
developing organism resulting from maternal pesticide exposure
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
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. Analysis. Developmental toxicity was observed, following in
utero exposure to bromoxynil, in multiple studies, by two routes of
exposure, and in three species. The induction of supernumerary ribs was
shown to be the most sensitive indicator of developmental toxicity in
fetal rats, mice, and (in certain studies) rabbits. In EPA's 1997
tolerance action concerning bromoxynil (62 FR 33019, June 18, 1997 ),
EPA concluded that the children's safety factor was not necessary to
protect the safety of infants and children. That decision rested on the
view that, given the large number of studies available on bromoxynil,
EPA had a high degree of certainty regarding the level at which effects
would occur in experimental animals. Since that action, EPA revisited
the children's safety factor decision and concluded that the safety
factor should be retained. This revised decision is based on EPA's
conclusion that the standard 100-fold safety factor may not be adequate
to protect the safety of infants and children given the clear showing
of increased susceptibility of fetuses, the steep dose response curve,
and the demonstrated severe developmental effects at doses above the
LOEL. Nevertheless, EPA's decision at this time remains tentative due
to the fact that EPA has only recently sought external science review
of its approach to the children's safety factor and also instituted an
internal reexamination process. Given the toxicological factors noted
above, EPA is unwilling to make safety determinations regarding this
pesticide without using the additional tenfold safety factor.
EPA believes that the population of concern for which the safety
factor should be retained is the developing fetus and the endpoint of
concern is supernumerary ribs. This endpoint, a developmental anomaly,
results from in utero exposure. Although some systems in infants and
children continue developing, it is unlikely that supernumerary ribs,
even though observed across multiple species, would result from
postnatal exposure. Since the acute dietary endpoint for females
13 years old is based on developmental effects, it was
determined that the 10-fold safety factor should be applied to the
acute risk assessment for females 13 years old (the
population subgroup that is relevant to in utero exposure), but is not
needed for children and infants. A 10-fold factor safety factor applied
to females 13 years old will provide additional protection
for infants and children and ensure a reasonable certainty of no harm
to this sensitive subpopulation.
2. Acute risk. The MOE of >5,000 for children 1-6 years old, the
most highly exposed subpopulation, is greater than the level of concern
of 100. For females 13 years old, the population subgroup
that is most relevant to the development of in utero exposure, the MOE
of 11,000 is greater than the level of concern of 1000. Therefore acute
risk for children does not trigger any concerns.
3. Chronic risk. Using the exposure assumptions described above,
EPA has concluded that aggregate exposure to bromoxynil from food will
utilize <1% of the RfD for infants and children. EPA generally has no
concern for exposures below 100% of the RfD because the RfD represents
the level at or below which daily aggregate dietary exposure over a
lifetime will not pose appreciable risks to human health. Therefore,
the Agency concludes that there is a reasonable certainty of no harm to
infants and children as a result of chronic dietary exposure to
bromoxynil.
III. Other Considerations
A. Metabolism In Plants and Animals
The nature (metabolism) of bromoxynil residues in plants and
livestock is adequately understood for the purposes of these
tolerances. In all the plant and animal (poultry and ruminants)
metabolism studies submitted, the residues of concern were parent
bromoxynil and the metabolite DBHA. The tolerances for cotton
commodities and livestock are expressed in terms of bromoxynil and
DBHA.
Pending receipt of additional metabolism data for DBHA in
livestock, the Agency has assumed that DBHA is of equal toxicity to the
parent and translates proportionately to the parent for livestock
commodities. The Agency believes these assumptions are adequately
protective for purposes of these tolerances.
B. Analytical Enforcement Methodology
Adequate analytical methodology is available for data collection
and tolerance enforcement for bromoxynil per se in plants. Method I in
PAM, Vol. II, is a GLC/MCD that has undergone a successful EPA method
validation on wheat grain. This method involves alkaline hydrolysis in
methanolic KOH to convert residues to bromoxynil, cleanup by liquid-
liquid partitioning, methylation using diazomethane, further cleanup on
a Florisil column, and determination by GLC/MCD. Method Ia is the same
method, but uses GC/ECD for determination of methylated bromoxynil.
[[Page 26479]]
The analytical method ``Bromoxynil: Method of Analysis for
Bromoxynil and its Metabolite, 3,5-Dibromo-4-hydroxybenzoic Acid in
Cottonseed, Gin Trash, and Seed Processed Fractions using GC-MSD.''
(Method RES9603) has been the subject of an Independent Laboratory
Validation (ILV) and an Agency Petition Method Validation (PMV). The
method validation data are being reviewed by the Agency; approval of
the method for enforcement purposes is anticipated.
Method A is a GC/MCD or ECD method for the analysis of bromoxynil
per se in livestock tissues and is essentially the same as Method I.
Method B is a GC/ECD method that is also similar to Method I, with
modifications to the cleanup procedures. A method for DBHA in animal
commodities has been developed and is currently in the process of
review and validation by the Agency.
C. Magnitude of Residues
In the petition for these tolerances, the registrant requested that
40 CFR 180.324 be amended by establishing tolerances for residues of
the herbicide bromoxynil and its metabolite DBHA on cotton at 7 ppm for
undelinted cottonseed, 50 ppm for cotton gin byproducts, and 21 ppm for
cotton hulls. These proposed tolerances are the same as those issued in
the June 18, 1997 final rule (62 FR 33019). Immediately prior to
establishing these tolerances, the registrant reduced the maximum label
rate as a result of Agency risk concerns. The tolerances were
determined by extrapolating from residue studies conducted at the
former maximum label rate (4.5 lb ai/A). Following the submission of
the tolerance petition, the registrant submitted residue data for
bromoxynil and DBHA in cotton commodities at the revised maximum
application rate of 3 applications at 0.5 lb ai/A each for a total of
1.5 lb ai/A. These data show that bromoxynil and DBHA residues in
cotton commodities are lower than the values determined for the June
18, 1997 final rule. Based on the new residue data, tolerances for
bromoxynil and DBHA in cotton commodities are being changed to 7.0 ppm
in cotton gin byproducts, 5.0 ppm in cotton hulls, and 1.5 ppm in
undelinted cottonseed.
In the June 18, 1997 final rule, tolerances for livestock
commodities (including milk and eggs) were expressed as bromoxynil per
se only; the Agency concluded that measurement of bromoxynil per se in
livestock commodities could serve as a marker to indicate the amount of
DBHA present in livestock. After further consideration, the Agency has
determined that measurement of bromoxynil per se in livestock is not
adequate to determine the amount of DBHA present. Therefore, in this
action, tolerances are expressed as bromoxynil and DBHA instead of only
as bromoxynil per se in livestock.
Tolerances for ruminant commodities (meat, fat, and meat by
products) were recalculated since issuing the June 18, 1997 final rule
due to new information. First, new residue data for bromoxynil and DBHA
in cotton commodities were used to determine expected maximum
theoretical dietary exposure to bromoxynil and DBHA via ingestion of
cotton commodities. Second, maximum theoretical residues in livestock
commodities were recalculated based on a revision in the dosing levels
used in livestock feeding studies. Doses were previously calculated in
terms of bromoxynil octanoate; however, since tolerances in RACs (raw
agricultural commodities) are for bromoxynil per se, doses were
recalculated as such. Finally, changes were made to the relative
contributions of feed items in the diet as a result of grazing
restrictions for grass, and information provided by the registrant on
the amount of cotton gin trash in beef and dairy cattle diets. These
changes did not affect tolerances for residues in milk, eggs, or meat
and fat of ruminants and poultry; however, the tolerances for residues
in meat by-products increased to 3.5 ppm for ruminants and to 0.3 ppm
for poultry.
D. International Residue Limits
There are no established or proposed Codex MRLs for bromoxynil
residues.
E. Rotational Crop Restrictions
Required additional limited field rotational crop studies have not
been submitted to the Agency; acceptable studies previously submitted
in support of reregistration reflect a maximum seasonal and single
application rate of 0.5 lb ai/A, but the use on cotton constitutes a
maximum seasonal application rate of 1.5 lb ai/A. Pending receipt of
these studies registered labels must restrict rotation of cotton fields
treated at a rate of greater than 0.5 lb ai/A/season to cotton.
IV. Conclusion
Therefore, tolerances are established for bromoxynil and DBHA in
undelinted cottonseed at 1.5 ppm, cotton gin byproducts at 7.0 ppm, and
cotton hulls at 5.0 ppm. In addition, this document establishes
tolerances for the residues of bromoxynil and DBHA, resulting from the
application of octanoic and heptanoic acid esters of bromoxynil to
cotton, in or on cattle, hogs, horses, goats, and sheep to 0.5 ppm in
meat, 3.5 ppm in mbyp, and 1.0 ppm in fat. Further, this document
establishes tolerances for residues of bromoxynil and DBHA, resulting
from the application of octanoic and heptanoic acid esters of
bromoxynil to cotton, at 0.1 ppm in milk; at 0.05 ppm in eggs; at 0.05
ppm in poultry meat and fat; and at 0.3 ppm in poultry mbyp.
V. Objections and Hearing Requests
The new FFDCA section 408(g) provides essentially the same process
for persons to ``object'' to a tolerance regulation issued by EPA under
new section 408(e) and (l)(6) as was provided in the old section 408
and in section 409. However, the period for filing objections is 60
days, rather than 30 days. EPA currently has procedural regulations
which govern the submission of objections and hearing requests. These
regulations will require some modification to reflect the new law.
However, until those modifications can be made, EPA will continue to
use those procedural regulations with appropriate adjustments to
reflect the new law.
Any person may, by July 13, 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).
[[Page 26480]]
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.
VI. Public Docket
EPA has established a record for this rulemaking under docket
control number [OPP-300661] (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:
[email protected].
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.
VII. Regulatory Assessment Requirements
This final rule establishes tolerances 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 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 1985, April 23,
1997).
In addition, since these tolerances and exemptions that are
established on the basis of a petition under FFDCA section 408(d), such
as the tolerances 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.
VIII. 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 6, 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. In Sec. 180.324, paragraph (a) is revised to read as follows:
Sec. 180.324 Bromoxynil; tolerances for residues.
(a) General. (1) Tolerances are established for residues of the
herbicide bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) resulting from
application of its octanoic and/or heptanoic acid ester in or on the
following commodities:
------------------------------------------------------------------------
Commodity Parts per million
------------------------------------------------------------------------
Alfalfa, seeding.......................... 0.1 ppm
Barley, grain............................. 0.1 ppm
Barley, straw............................. 0.1 ppm
Corn, fodder (dry)........................ 0.1 ppm
Corn, fodder (green)...................... 0.1 ppm
Corn, fodder, field (dry)................. 0.1 ppm
Corn, fodder, field (green)............... 0.1 ppm
Corn, grain............................... 0.1 ppm
Corn, grain, field........................ 0.1 ppm
Flaxseed.................................. 0.1 ppm
Flax straw................................ 0.1 ppm
Garlic.................................... 0.1 ppm
Grass, canary, annual, seed............... 0.1 ppm
Grass, canary, annual, straw.............. 0.1 ppm
Mint hay.................................. 0.1 ppm
Oats, forage, green....................... 0.1 ppm
Oats, grain............................... 0.1 ppm
Oats, straw............................... 0.1 ppm
Onions (dry bulb)......................... 0.1 ppm
Rye, forage, green........................ 0.1 ppm
Rye, grain................................ 0.1 ppm
Rye, straw................................ 0.1 ppm
Sorghum, fodder........................... 0.1 ppm
Sorghum, forage........................... 0.1 ppm
Sorghum, grain............................ 0.1 ppm
Wheat, forage, green...................... 0.1 ppm
Wheat, grain.............................. 0.1 ppm
Wheat, straw.............................. 0.1 ppm
------------------------------------------------------------------------
(2) Tolerances are established for residues of the herbicide
bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) and its metabolite 3,5-
dibromo-4-hydroxybenzoic acid (DBHA) resulting from application of its
octanoic and/or heptanoic acid ester in or on the following
commodities:
[[Page 26481]]
------------------------------------------------------------------------
Commodity Parts per million
------------------------------------------------------------------------
Cattle, fat............................... 1 ppm
Cattle, mbyp.............................. 3.5 ppm
Cattle, meat.............................. 0.5 ppm
Cotton gin byproducts..................... 7.0 ppm
Cotton, hulls............................. 5.0 ppm
Cotton, undelinted seed................... 1.5 ppm
Eggs...................................... 0.05 ppm
Goats, fat................................ 1 ppm
Goats, mbyp............................... 3.5 ppm
Goats, meat............................... 0.5 ppm
Hogs, fat................................. 1 ppm
Hogs, mbyp................................ 3.5 ppm
Hogs, meat................................ 0.5 ppm
Horses, fat............................... 1 ppm
Horses, mbyp.............................. 3.5 ppm
Horses, meat.............................. 0.5 ppm
Milk...................................... 0.1 ppm
Poultry, fat.............................. 0.05 ppm
Poultry, mbyp............................. 0.3 ppm
Poultry, meat............................. 0.05 ppm
Sheep, fat................................ 1 ppm
Sheep, mbyp............................... 3.5 ppm
Sheep, meat............................... 0.5 ppm
------------------------------------------------------------------------
* * * * *
[FR Doc. 98-12639 Filed 5-8-98; 9:42 am]
BILLING CODE 6560-50-F