[Federal Register Volume 64, Number 241 (Thursday, December 16, 1999)]
[Rules and Regulations]
[Pages 70184-70191]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-32652]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-300950; FRL-6391-8]
RIN 2070-AB78
Metsulfuron methyl; Pesticide Tolerances for Emergency Exemptions
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes time-limited tolerances for the
combined residues of metsulfuron methyl and its 4-hydroxy metabolite
(methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-
yl)amino]carbonyl]amino]sulfonyl]-4-hydroxybenzoate) in or on sorghum
grain, sorghum forage, and sorghum fodder. 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 the use
of the pesticide on sorghum. This
[[Page 70185]]
regulation establishes maximum permissible levels for residues of
metsulfuron-methyl on these food commodities. The tolerances will
expire and be revoked on December 31, 2001.
DATES: This regulation is effective December 16, 1999. Objections and
requests for hearings, identified by docket control number OPP-300950,
must be received by EPA on or before February 14, 2000.
ADDRESSES: Written objections and hearing requests may be submitted by
mail, in person, or by courier. Please follow the detailed instructions
for each method as provided in Unit VII. of the ``SUPPLEMENTARY
INFORMATION.'' To ensure proper receipt by EPA, your objections and
hearing requests must identify docket control number OPP-300950 in the
subject line on the first page of your response.
FOR FURTHER INFORMATION CONTACT: By mail: Andrew Ertman, Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460; telephone
number: (703) 308-9367; and e-mail address: ertman.andrew@epa.gov.
SUPPLEMENTARY INFORMATION:
I. General Information
A. Does this Action Apply to Me?
You may be potentially affected by this action if you are an
agricultural producer, food manufacturer, or pesticide manufacturer.
Potentially affected categories and entities may include, but are not
limited to:
------------------------------------------------------------------------
Examples of
Categories NAICS codes potentially
affected entities
------------------------------------------------------------------------
Industry 111 Crop production
112 Animal production
311 Food manufacturing
32532 Pesticide
manufacturing
------------------------------------------------------------------------
This listing is not intended to be exhaustive, but rather provides
a guide for readers regarding entities likely to be affected by this
action. Other types of entities not listed in the table could also be
affected. The North American Industrial Classification System (NAICS)
codes have been provided to assist you and others in determining
whether or not this action might apply to certain entities. If you have
questions regarding the applicability of this action to a particular
entity, consult the person listed under ``FOR FURTHER INFORMATION
CONTACT.''
B. How Can I Get Additional Information, Including Copies of This
Document and Other Related Documents?
1. Electronically.You may obtain electronic copies of this
document, and certain other related documents that might be available
electronically, from the EPA Internet Home Page at http://www.epa.gov/.
To access this document, on the Home Page select ``Laws and
Regulations'' and then look up the entry for this document under the
``Federal Register--Environmental Documents.'' You can also go directly
to the Federal Register listings at http://www.epa.gov/fedrgstr/.
2. In person. The Agency has established an official record for
this action under docket control number OPP-300950. The official record
consists of the documents specifically referenced in this action, and
other information related to this action, including any information
claimed as Confidential Business Information (CBI). This official
record includes the documents that are physically located in the
docket, as well as the documents that are referenced in those
documents. The public version of the official record does not include
any information claimed as CBI. The public version of the official
record, which includes printed, paper versions of any electronic
comments submitted during an applicable comment period is available for
inspection in the Public Information and Records Integrity Branch
(PIRIB), Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy.,
Arlington, VA, from 8:30 a.m. to 4 p.m., Monday through Friday,
excluding legal holidays. The PIRIB telephone number is (703) 305-5805.
II. Background and Statutory Findings
EPA, on its own initiative, in accordance with sections 408(l)(6)
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a, is
establishing tolerances for the combined residues of the herbicide
metsulfuron methyl and its 4-hydroxy metabolite (methyl 2-[[[[(4-
methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino]sulfonyl]-4-
hydroxybenzoate) in or on sorghum grain at 0.4 part per million (ppm);
sorghum forage at 0.3 ppm; and sorghum fodder at 0.5 ppm. These
tolerances will expire and are revoked on December 31, 2001. EPA will
publish a document in the Federal Register to remove the revoked
tolerances from the Code of Federal Regulations.
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. EPA does not intend for its actions on
section 18 related tolerances to set binding precedents for the
application of section 408 and the new safety standard to other
tolerances and exemptions.
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 the Federal Insecticide, Fungicide, and Rodenticide
Act (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
the Food Quality Protection Act (FQPA). EPA has established regulations
governing such emergency exemptions in 40 CFR part 166.
III. Emergency Exemption for Metsulfuron-methyl on Sorghum and
FFDCA Tolerances
The current emergency situation was brought about by the loss of
the chemical propazine as a section 18 chemical. The use of propazine
as a preemergent application in grain sorghum was very efficacious.
However, with its loss, grain sorghum producers are relying more on
postemergent applications. Sorghum grows slowly in the early seedling
stage and is susceptible to weed interference the first 2 to 3 weeks
after crop emergence. This is especially the case in light soils where
surface moisture is the major limiting growth factor. The use of
methsulfuron methyl with 2,4-D
[[Page 70186]]
provides the producer with a wider window of application (sorghum that
is 3-15'' tall) than registered alternatives.
In addition, there is less flexibility in rotation of crops after
sorghum because of the carry-over problems that exist with registered
alternatives, primarily atrazine. The applicants asserted that the
inability to rotate other crops after sorghum will result in
significant loss of income to producers. EPA has authorized under FIFRA
section 18 the use of metsulfuron methyl on sorghum for control of
weeds in Kansas, Oklahoma, and Texas.
As part of its assessment of this emergency exemption, EPA assessed
the potential risks presented by residues of metsulfuron methyl in or
on sorghum. In doing so, EPA considered the safety standard in FFDCA
section 408(b)(2), and EPA decided that the necessary tolerances under
FFDCA section 408(l)(6) would be consistent with the 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 these tolerances without notice and opportunity for public
comment as provided in section 408(l)(6). Although these tolerances
will expire and are revoked on December 31, 2001, under FFDCA section
408(l)(5), residues of the pesticide not in excess of the amounts
specified in the tolerances remaining in or on sorghum grain, forage,
or fodder 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 these tolerances at the time
of that application. EPA will take action to revoke these tolerances
earlier if any experience with, scientific data on, or other relevant
information on this pesticide indicate that the residues are not safe.
Because these tolerances are being approved under emergency
conditions, EPA has not made any decisions about whether metsulfuron
methyl meets EPA's registration requirements for use on sorghum or
whether permanent tolerances for this use would be appropriate. Under
these circumstances, EPA does not believe that these tolerances serve
as a basis for registration of metsulfuron methyl by a State for
special local needs under FIFRA section 24(c). Nor do these tolerances
serve as the basis for any State other than Kansas, Oklahoma, and Texas
to use this pesticide on this crop under section 18 of FIFRA without
following all provisions of EPA's regulations implementing section 18
as identified in 40 CFR part 166. For additional information regarding
the emergency exemption for metsulfuron methyl, contact the Agency's
Registration Division at the address provided under ``FOR FURTHER
INFORMATION CONTACT.''
IV. Aggregate Risk Assessment and Determination of Safety
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 and a complete description of
the risk assessment process, see the final rule on Bifenthrin Pesticide
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).
Consistent with section 408(b)(2)(D), EPA has reviewed the
available scientific data and other relevant information in support of
this action. EPA has sufficient data to assess the hazards of
metsulfuron methyl and to make a determination on aggregate exposure,
consistent with section 408(b)(2), for time-limited tolerances for the
combined residues of the herbicide metsulfuron methyl and its 4-hydroxy
metabolite (methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-
yl)amino]carbonyl]amino]sulfonyl]-4-hydroxybenzoate) in or on sorghum
grain at 0.4 ppm; sorghum forage at 0.3 ppm; and sorghum fodder at 0.5
ppm. 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 metsulfuron methyl
are discussed in this unit.
B. Toxicological Endpoint
1. Acute toxicity. For acute dietary and aggregate risk
assessments, the Agency established an acute reference dose (RfD) of
0.25 milligram/kilogram/day (mg/kg/day). This RfD was based on
decreased body weight gain seen on gestation days 6-9 in the prenatal
developmental toxicity study in rabbits. The no observed adverse effect
level (NOAEL) was 25 mg/kg/day and an uncertainty factor of 100 was
applied.
Because the potential for additional sensitivity of infants and
children to residues of metsulfuron methyl was not assessed by the
Agency, for the purposes of this section 18 only, the FQPA 10x safety
factor will be retained. Therefore the acute Population Adjusted Dose
(aPAD) is 0.025 mg/kg/day.
2. Short- and intermediate-term toxicity. For short- and
intermediate-term dermal toxicity, the Agency established an endpoint
of 500.0 mg/kg/day. The lowest observed adverse effect level (LOAEL)
was 2,000 mg/kg/day, based on diarrhea in the 21-day dermal toxicity
study in rats. Margin of exposures (MOEs) must be equal to or greater
than 100 to be considered to be acceptable (i.e., to not exceed EPA's
level of concern). A long-term dermal endpoint was not established for
this use because long-term exposure is not expected.
3. Chronic toxicity. EPA has established the RfD for metsulfuron
methyl at 0.25 mg/kg/day. This RfD is based on decreased body weight in
the 2-year rat study. The NOAEL was 25 mg/kg/day and an uncertainty
factor of 100 was applied.
Because the potential for additional sensitivity of infants and
children to residues of metsulfuron methyl was not assessed by the
Agency, for the purposes of this section 18 only, the FQPA 10x safety
factor will be retained. Therefore the chronic Population Adjusted Dose
(cPAD) is 0.025 mg/kg/day.
4. Carcinogenicity. Metsulfuron methyl is classified as a class E
compound (not likely to be a human carcinogen). This classification was
based on a 2-year rat study (HDT = 5,000 ppm, 250 mg/kg/day) and an 18-
month mouse study (HDT = 5,000 ppm, 714 mg/kg/day).
C. Exposures and Risks
1. From food and feed uses. Tolerances have been established (40
CFR 180.428) for the combined residues of metsulfuron methyl and its
metabolite (methyl 2-[[[[(4-methoxy-6-methyl-1,3,5 triazin-2-
yl)amino]carbonyl]amino]sulfonyl]-4-hydroxybenzoate) in or on barley,
grass, sugarcane, and wheat. These tolerances range from 0.1 ppm to 20
ppm. Tolerances are also established for metsulfuron methyl residues in
milk and on the fat, meat, meat byproducts, and kidney of cattle,
goats, hogs, horses, and sheep. These animal commodity tolerances range
from 0.05 ppm in milk to 0.5 ppm in kidney. Results of a poultry
feeding study indicate that residues will not be present in poultry
commodities. Risk assessments were conducted by EPA to assess dietary
[[Page 70187]]
exposures and risks from metsulfuron methyl as follows:
i. Acute exposure and risk. Acute dietary risk assessments are
performed for a food-use pesticide if a toxicological study has
indicated the possibility of an effect of concern occurring as a result
of a 1-day or single exposure. In conducting this acute dietary risk
assessment, EPA made very conservative assumptions: 100% crop treated
is assumed for all crops and residues will be at the level of the
tolerance.
The aPAD (0.025 mg/kg/day) is the level above which exposure of a
subgroup exceeds EPA's level of concern. The exposures of all
population subgroups (as well as the exposure of the U.S. population as
a whole) are expressed as percentages of the aPAD. Therefore, exposures
above 100% aPAD exceed EPA's level of concern. The existing metsulfuron
methyl tolerances (published, pending, and including the necessary
section 18 tolerance(s)) result in exposures that are equivalent to the
following percentages of the aPAD: The U.S. population (8%), non-
nursing infants < 1="" year="" old="" (20%),="" and="" females="" 13+,="" nursing="" (6%).="" the="" most="" highly="" exposed="" subgroup="" is="" non-nursing="" infants="">< 1="" year)="" which="" uses="" 20%="" of="" the="" apad.="" the="" exposure="" to="" metsulfuron="" methyl="" of="" the="" u.s.="" population="" and="" all="" population="" subgroups="" is="" below="" epa's="" level="" of="" concern.="" ii.="" chronic="" exposure="" and="" risk.="" as="" with="" the="" acute="" analysis,="" in="" conducting="" this="" chronic="" dietary="" risk="" assessment,="" the="" agency="" made="" very="" conservative="" assumptions:="" 100%="" crop="" treated="" is="" assumed="" for="" all="" crops="" and="" residues="" will="" be="" at="" the="" level="" of="" the="" tolerance.="" the="" novigen="" dietary="" exposure="" evaluation="" model="" (deem)="" system="" was="" used="" for="" this="" chronic="" dietary="" exposure="" analysis.="" the="" cpad="" (also="" 0.025="" mg/kg/day)="" is="" analogous="" to="" the="" apad="" (see="" discussion="" of="" apad,="" above).="" the="" existing="" metsulfuron="" methyl="" tolerances="" (published,="" pending,="" and="" including="" the="" necessary="" section="" 18="" tolerance(s))="" result="" in="" exposures="" that="" are="" equivalent="" to="" the="" following="" percentages="" of="" the="" cpad:="" the="" u.s.="" population="" (3%),="" children="" 1-6="" years="" old="" (8%),="" and="" females="" 13+="" pregnant,="" not="" nursing="" (2%).="" the="" most="" highly="" exposed="" subgroup,="" children="" 1-6="" years,="" uses="" 8%="" of="" the="" cpad.="" the="" exposure="" of="" the="" u.s.="" population="" and="" all="" population="" subgroups="" is="" below="" epa's="" level="" of="" concern.="" 2.="" from="" drinking="" water.="" metsulfuron="" methyl="" is="" persistent="" and="" mobile.="" there="" is="" no="" established="" maximum="" contaminant="" level="" (mcls)="" for="" residues="" of="" metsulfuron="" methyl="" in="" drinking="" water.="" no="" health="" advisory="" levels="" for="" metsulfuron="" methyl="" in="" drinking="" water="" have="" been="" established.="" estimates="" for="" the="" concentration="" of="" metsulfuron="" methyl="" in="" surface="" water="" were="" based="" on="" generic="" estimated="" environmental="" concentration="" (geneec)="" modeling="" and="" in="" ground="" water="" based="" on="" screening="" concentration="" in="" ground="" water="" (sci-grow)="" modeling.="" the="" maximum="" application="" rate="" of="" metsulfuron="" methyl="" (0.015="" lb="" ai/acre)="" is="" on="" pasture="" and="" rangeland.="" i.="" acute="" exposure="" and="" risk.="" the="" peak="" surface="" water="" estimated="" concentration="" for="" metsulfuron="" methyl="" is="" 0.63="" parts="" per="" billion="" (ppb).="" the="" ground="" water="" estimated="" concentration="" is="" 0.093="" ppb.="" for="" purposes="" of="" risk="" assessment,="" the="" maximum="" eec="" for="" metsulfuron="" methyl="" in="" surface="" water="" (0.63="" ppb)="" should="" be="" used="" for="" comparison="" to="" the="" back-calculated="" human="" health="" drinking="" water="" levels="" of="" comparison="" (dwloc)="" for="" the="" acute="" endpoint.="" the="" estimated="" maximum="" concentrations="" of="" metsulfuron="" methyl="" in="" surface="" water="" and="" ground="" water="" are="" less="" than="" epa's="" levels="" of="" comparison="" for="" metsulfuron="" methyl="" in="" drinking="" water="" as="" a="" contribution="" to="" acute="" aggregate="" exposure.="" the="" population="" subgroup="" with="" the="" highest="" dietary="" exposure="" is="" non-nursing="" infants.="" the="" dwloc="" for="" this="" group="" is="" 200="" micrograms/liter="">g/L). The DWLOCs for all population
subgroups exceed the maximum acute estimated environmental
concentrations (EEC) of 0.63. Therefore, taking into account the
present uses and uses proposed in this section 18, EPA concludes with
reasonable certainty that residues of metsulfuron methyl in drinking
water (when considered along with other sources of chronic exposure for
which EPA has reliable data) would not result in an unacceptable
estimate of acute aggregate human health risk at this time.
EPA bases this determination on a comparison of estimated maximum
concentrations of metsulfuron methyl in surface and ground water to
back-calculated DWLOCs for metsulfuron methyl in drinking water. These
levels of comparison in drinking water were determined after EPA
considered all other non-occupational human exposures for which it has
reliable data (there are no residential uses), including all current
uses, and the use considered in this action. The estimate of
metsulfuron methyl in surface water is derived from a water quality
model that uses conservative assumptions (health-protective) regarding
the pesticide transport from the point of application to surface and
ground water. Because EPA considers the aggregate risk resulting from
multiple exposure pathways associated with a pesticide's uses, levels
of comparison in drinking water may vary as those uses change. If new
uses are added in the future, EPA will reassess the potential impacts
of metsulfuron methyl in drinking water as a part of the acute
aggregate risk assessment process.
ii. Chronic exposure and risk. The 56-day average surface water
estimated concentration for metsulfuron methyl is 0.61 ppb. The ground
water estimated concentration is 0.093 ppb. For purposes of risk
assessment, the average EEC for metsulfuron methyl in surface water
(0.61 ppb) should be used for comparison to the back-calculated human
health drinking water levels of comparison (DWLOC) for the chronic
(non-cancer) endpoint.
The estimated average concentrations of metsulfuron methyl in
surface water and ground water are less than EPA's levels of comparison
for metsulfuron methyl in drinking water as a contribution to chronic
aggregate exposure. The population subgroup with the highest dietary
exposure is children 1-6 years old. The DWLOC for this subgroup is 230
g/L. The DWLOCs for all population subgroups exceed the
chronic average EEC of 0.61 ppb. Therefore, taking into account the
present uses and uses proposed in this section 18 and the fact that
GENEEC can substantially overestimate (by up to 3x) true pesticide
concentrations in drinking water, EPA concludes with reasonable
certainty that residues of metsulfuron methyl in drinking water (when
considered along with other sources of chronic exposure for which the
Agency has reliable data) would not result in an unacceptable estimate
of chronic (non-cancer) aggregate human health risk at this time.
EPA bases this determination on a comparison of estimated average
concentrations of metsulfuron methyl in surface and ground water to
back-calculated DWLOCs for metsulfuron methyl in drinking water. These
levels of comparison in drinking water were determined after EPA
considered all other non-occupational human exposures for which it has
reliable data (there are no residential uses), including all current
uses, and the use considered in this action. The estimate of
metsulfuron methyl in surface water is derived from a water quality
model that uses conservative assumptions (health-protective) regarding
the pesticide transport from the point of application to surface and
ground water. Because the Agency considers the aggregate risk resulting
from multiple exposure pathways associated with a pesticide's
[[Page 70188]]
uses, levels of comparison in drinking water may vary as those uses
change. If new uses are added in the future, the Agency will reassess
the potential impacts of metsulfuron methyl in drinking water as a part
of the chronic (non-cancer) aggregate risk assessment process.
3. From non-dietary exposure. Metsulfuron methyl is not currently
registered for use on residential non-food sites. Because there are no
residential uses registered, a risk assessment on acute exposure,
chronic exposure, and short- and intermediate-term exposures relating
to non-dietary exposures were not conducted.
4. Cumulative exposure to substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) requires that, when considering
whether to establish, modify, or revoke a tolerance, the Agency
consider ``available information'' concerning the cumulative effects of
a particular pesticide's residues and ``other substances that have a
common mechanism of toxicity.''
EPA does not have, at this time, available data to determine
whether metsulfuron methyl 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,
metsulfuron methyl 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 metsulfuron methyl has a
common mechanism of toxicity with other substances. For more
information regarding EPA's efforts to determine which chemicals have a
common mechanism of toxicity and to evaluate the cumulative effects of
such chemicals, see the final rule for Bifenthrin Pesticide Tolerances
(62 FR 62961, November 26, 1997).
D. Aggregate Risks and Determination of Safety for U.S. Population
1. Acute risk. Acute aggregate exposure risk assessment is limited
to food + water only because there are no residential uses registered.
The risk from acute exposure to metsulfuron methyl in food and drinking
water is below the Agency's level of concern for the U.S. population
and all population subgroups. See Units IV.C.1.i. and IV.C.2.i. for
details on this topic.
2. Chronic risk. There are no registered residential uses or
registered uses which will result in application or post-application
residential exposure; therefore, aggregate exposure risk assessment
will be limited to food + water only. The risk from chronic exposure to
metsulfuron methyl in food and drinking water is below the Agency's
level of concern for the U.S. population and all population subgroups.
See Units IV.C.1.i. and IV.C.2.i. for details on this topic.
3. Short- and intermediate-term risk. Short- and intermediate-term
aggregate exposure takes into account chronic dietary food and water
(considered to be a background exposure level) plus indoor and outdoor
residential exposure.
There are no registered residential uses or registered uses which
will result in application or post-application residential exposure;
therefore, these aggregate exposure risk assessments are not required.
See section (C)(3) for details on this topic.
4. Aggregate cancer risk for U.S. population. Metsulfuron methyl
has been classified by the Agency as a class E compound (not likely to
be a human carcinogen); therefore, a cancer risk assessment is not
required.
5. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
from aggregate exposure to metsulfuron methyl residues.
E. Aggregate Risks and Determination of Safety for Infants and Children
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 prenatal and postnatal toxicity and
the completeness of the data base unless EPA determines that a
different margin of safety will be safe for infants and children.
Margins of safety are incorporated into EPA risk assessments either
directly through use of a 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
interspecies and intraspecies 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.
A conservative risk assessment for expedited actions (i.e., section
18s) may be performed, assuming that an FQPA safety factor of 10x is
retained. If risk estimates do not exceed the Agency's level of concern
under these circumstances, the action can go forward, noting that the
safety factor determination applies only to this action and is subject
to change when the chemical undergoes full review by the FQPA Safety
Factor Committee. Because the potential for additional sensitivity of
infants and children to residues of metsulfuron methyl was not assessed
by the Agency, for the purposes of this section 18 only, the FQPA 10x
safety factor will be retained. Therefore, the MOE/safety factor is
1,000.
As noted above, because the Agency did an expedited conservative
risk assessment, for the purposes of this section 18 only, the FQPA 10x
safety factor will be retained. Therefore, both the aPAD and cPAD are
0.025 mg/kg/day, adding the additional 10x to the RfDs of 0.25 mg/kg/
day.
1. Acute risk. Using the exposure assumptions described in this
unit, EPA has concluded that aggregate exposure to metsulfuron methyl
from food will utilize between 4% and 20% of the aPAD for infants and
children. EPA generally has no concern for exposures below 100% of the
aPAD because the aPAD represents the level at or below which acute
dietary exposure will not pose appreciable risks to human health.
The estimated maximum concentrations of metsulfuron methyl in
surface water and ground water are less than EPA's levels of comparison
for metsulfuron methyl in drinking water as a contribution to acute
aggregate exposure. The population subgroup with the highest dietary
exposure is non-nursing infants. The DWLOC for this group is 200
g/L. The DWLOCs for all population subgroups exceed the
maximum acute EEC of 0.63. Therefore, taking into account the present
uses and uses proposed in this section 18, EPA concludes with
reasonable certainty that residues of metsulfuron methyl in drinking
water (when considered along with other sources of chronic exposure for
which EPA has reliable data) would not result in an unacceptable
estimate of acute aggregate human health risk at this time.
2. Chronic risk. Using the exposure assumptions described in this
unit, EPA has concluded that aggregate exposure to metsulfuron methyl
from food will utilize between 1% and 8% of the cPAD for infants and
children. EPA generally has no concern for exposures below 100% of the
cPAD because the cPAD represents the level at or below which daily
aggregate dietary exposure over a lifetime will not pose appreciable
risks to human health.
The estimated average concentrations of metsulfuron methyl in
surface water
[[Page 70189]]
and ground water are less than EPA's levels of comparison for
metsulfuron methyl in drinking water as a contribution to chronic
aggregate exposure. The population subgroup with the highest dietary
exposure is children 1-6 years old. The DWLOC for this subgroup is 230
g/L. The DWLOCs for all population subgroups exceed the
chronic average EEC of 0.61 ppb. Therefore, taking into account the
present uses and uses proposed in this section 18 and the fact that
GENEEC can substantially overestimate (by up to 3x) true pesticide
concentrations in drinking water, EPA concludes with reasonable
certainty that residues of metsulfuron methyl in drinking water (when
considered along with other sources of chronic exposure for which EPA
has reliable data) would not result in an unacceptable estimate of
chronic (non-cancer) aggregate human health risk at this time.
3. Short- or intermediate-term risk. There are no registered
residential uses or registered uses which will result in application or
post-application residential exposure; therefore, these aggregate
exposure risk assessments are not required.
4. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to infants and children from aggregate exposure to metsulfuron methyl
residues.
V. Other Considerations
A. Metabolism in Plants and Animals
1. Plants. The nature of the residue is understood for cereal
grains. The residue to be regulated consists of metsulfuron methyl and
its metabolites methyl 2-[[[[(4-methyoxy-6-methyltriazin-2-
yl)amino]carbonyl]amino]sulfonyl]-4-beta-D-glycopyranosylbenzoate
(metabolite A) and methyl 2-[[[[(4-methoxy-6-methyltriazin-2-
yl)amino]carbonyl]amino]sulfonyl]-4-hydroxybenzoate (metabolite A1).
The latter metabolite can be formed from metabolite A through enzymatic
hydrolysis.
2. Animals. Metabolism studies were conducted for metsulfuron
methyl in rat and goat and metabolite A in goat. The residue to be
regulated was determined to be parent only. Metsulfuron methyl was the
major component in milk. Saccharin was the major component in liver and
was judged not to be of concern. Levels in other tissues were
20 ppb. However, the dose level of 3.4 ppm in the diet was
only about equal to the calculated dietary intake, and there are no
studies in which the triazine moiety was labeled. Liver and milk were
the only tissues characterized, and a sample chromatogram was submitted
from the milk analysis only. A subsequent petition (for grass forage,
hay and fodder) resulted in a potentially higher contribution to the
diet of ruminants 15 ppm. Any subsequent use which results in a
significant contribution to the dietary intake of the herbicide will
require submission of a new ruminant metabolism study in which the
triazine portion of the molecule is labeled, the dose level is
appropriate ( 1x rate and at least 10 ppm) and residues in
muscle, fat, kidney, liver and milk are fully characterized.
Sorghum grain can constitute up to 80% of the diet of poultry. A
poultry metabolism study has been submitted, but has not been fully
reviewed by the Agency. The results were similar to the results of the
goat and rat metabolism studies in that parent metsulfuron methyl was
excreted largely unchanged. A minor portion was metabolized to O-
desmethyl metsulfuron methyl. As a result, EPA concludes that for the
purposes of this section 18 the nature of the residue in poultry is
understood.
B. Analytical Enforcement Methodology
1. Plants. An adequate analytical method is available for
enforcement of the proposed tolerances in sorghum. This method (AMR
1797-90, Revision No. 1: Analytical Method for the Quantitation of DPX-
T6376 (Ally) in Wheat Grain and Straw,'' 1991) is an HPLC method. The
limit of quantitation (LOQ) is based on spike recoveries and is
reportedly 0.050 ppm for sorghum grain and 0.10 ppm for forage hay and
stover. For processed commodities, the LOQ for process and steep water
fractions was 0.02 ppm and the LOQ for all other fractions was 0.050
ppm. Metabolites A and A1 were determined by a procedure derived from
Dupont's AMR 238-84 and AMR 1934-91, Revision 1. This method is also an
HPLC method and has the same quantitation limits as the method for
parent does. In this procedure, metabolite A is converted to metabolite
A1. As a result, the residue of concern is parent and metabolite A1.
In addition to the methods described above, two regulatory
analytical methods are also given in PAM II for metsulfuron methyl and
its metabolites. The method for metsulfuron methyl is titled ``High-
Performance Liquid Chromatographic Determination of Metsulfuron Methyl
Residues in Crops,'' L.W. Hershberger, DuPont Document No. AMR-104-82,
Revision B, February 20, 1986. [PAM II, Method I]. The method for the
metabolites is: ``High-Performance Liquid Chromatographic Determination
of Residues of Metsulfuron Methyl Metabolites A and A1 in Cereal Grain
Crops,'' L.W. Hershberger, Du Pont Document No. AMR-238-84, Revision B,
March 27, 1986. [PAM II, Method III]
Adequate analytical methodology is available for enforcement of the
proposed tolerances.
2. Animals. A method is available for enforcement of tolerances in
bovine tissues and milk (Method II in PAM II).
C. Magnitude of Residues
Residues of metsulfuron methyl and its 4-hydroxy metabolite (methyl
2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]-
amino]sulfonyl]-4-hydroxybenzoate) are not expected to exceed the
following levels: sorghum grain at 0.4 part per million (ppm); sorghum
forage at 0.3 ppm; and sorghum fodder at 0.5 ppm.
D. International Residue Limits
There are no Codex, Canadian, or Mexican Maximum Residue Limits
(MRLs) for metsulfuron methyl on sorghum.
E. Rotational Crop Restrictions
Minimum rotation intervals of 1 to 22 months are specified
explicitly for wheat, field corn, soybeans, and cotton. For all other
crops, the minimum rotation interval is 34 months.
VI. Conclusion
Therefore, the tolerance is established for the combined residues
of the herbicide metsulfuron methyl and its 4-hydroxy metabolite
(methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]-
amino]sulfonyl]-4-hydroxybenzoate) in or on sorghum grain at 0.4 part
per million (ppm); sorghum forage at 0.3 ppm; and sorghum fodder at 0.5
ppm.
VII. Objections and Hearing Requests
Under section 408(g) of the FFDCA, as amended by the FQPA, any
person may file an objection to any aspect of this regulation and may
also request a hearing on those objections. The EPA procedural
regulations which govern the submission of objections and requests for
hearings appear in 40 CFR part 178. Although the procedures in those
regulations require some modification to reflect the amendments made to
the FFDCA by the FQPA of 1996, EPA will continue to use those
procedures, with appropriate adjustments, until the necessary
modifications can be made. The new section 408(g) provides essentially
the same process for persons
[[Page 70190]]
to ``object'' to a regulation for an exemption from the requirement of
a tolerance issued by EPA under new section 408(d), as was provided in
the old FFDCA sections 408 and 409. However, the period for filing
objections is now 60 days, rather than 30 days.
A. What Do I Need to Do to File an Objection or Request a Hearing?
You must file your objection or request a hearing on this
regulation in accordance with the instructions provided in this unit
and in 40 CFR part 178. To ensure proper receipt by EPA, you must
identify docket control number OPP-300950 in the subject line on the
first page of your submission. All requests must be in writing, and
must be mailed or delivered to the Hearing Clerk on or before February
14, 2000.
1. Filing the request. Your objection must specify the specific
provisions in the regulation that you object to, and the grounds for
the objections (40 CFR 178.25). If a hearing is requested, the
objections must include a statement of the factual issues(s) on which a
hearing is requested, the requestor's contentions on such issues, and a
summary of any evidence relied upon by the objector (40 CFR 178.27).
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.
Mail your written request to: Office of the Hearing Clerk (1900),
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460.
You may also deliver your request to the Office of the Hearing Clerk in
Rm. M3708, Waterside Mall, 401 M St., SW., Washington, DC 20460. The
Office of the Hearing Clerk is open from 8 a.m. to 4 p.m., Monday
through Friday, excluding legal holidays. The telephone number for the
Office of the Hearing Clerk is (202) 260-4865.
2. Tolerance fee payment. If you file an objection or request a
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must
mail the fee to: EPA Headquarters Accounting Operations Branch, Office
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please
identify the fee submission by labeling it ``Tolerance Petition Fees.''
EPA is authorized to waive any fee requirement ``when in the
judgement of the Administrator such a waiver or refund is equitable and
not contrary to the purpose of this subsection.'' For additional
information regarding the waiver of these fees, you may contact James
Tompkins by phone at (703) 305-5697, by e-mail at tompkins.jim@epa.gov,
or by mailing a request for information to Mr. Tompkins at Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460.
If you would like to request a waiver of the tolerance objection
fees, you must mail your request for such a waiver to: James Hollins,
Information Resources and Services Division (7502C), Office of
Pesticide Programs, Environmental Protection Agency, 401 M St., SW.,
Washington, DC 20460.
3. Copies for the Docket. In addition to filing an objection or
hearing request with the Hearing Clerk as described in Unit VII.A., you
should also send a copy of your request to the PIRIB for its inclusion
in the official record that is described in Unit I.B.2. Mail your
copies, identified by the docket control number OPP-300950, 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 or
by courier, bring a copy to the location of the PIRIB described in Unit
I.B.2. You may also send an electronic copy of your request via e-mail
to: opp-docket@epa.gov. Please use an ASCII file format and avoid the
use of special characters and any form of encryption. Copies of
electronic objections and hearing requests will also be accepted on
disks in WordPerfect 6.1/8.0 file format or ASCII file format. Do not
include any CBI in your electronic copy. You may also submit an
electronic copy of your request at many Federal Depository Libraries.
B. When Will the Agency Grant a Request for a Hearing?
A request for a hearing will be granted if the Administrator
determines that the material submitted shows the following: There is a
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(s) in the manner sought
by the requestor would be adequate to justify the action requested (40
CFR 178.32).
VIII. Regulatory Assessment Requirements
This final rule establishes a time-limited tolerance under FFDCA
section 408. 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) (Public Law 104-4). Nor does it require any prior consultation
as specified by Executive Order 13084, entitled Consultation and
Coordination with Indian Tribal Governments (63 FR 27655, May 19,
1998); 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 or any Agency action under Executive Order 13045,
entitled Protection of Children from Environmental Health Risks and
Safety Risks (62 FR 19885, April 23, 1997). This action does not
involve any technical standards that would require Agency consideration
of voluntary consensus standards pursuant to section 12(d) of the
National Technology Transfer and Advancement Act of 1995 (NTTAA),
Public Law 104-113, section 12(d) (15 U.S.C. 272 note). Since
tolerances and exemptions that are established on the basis of a FIFRA
section 18 petition under FFDCA section 408, 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. In addition, the Agency has determined that this
action will not have a substantial direct effect on States, on the
relationship between the national government and the States, or on the
distribution of power and responsibilities among the various levels of
government, as specified in Executive Order 13132, entitled Federalism
(64 FR 43255, August 10, 1999). Executive Order 13132 requires EPA to
develop an accountable process to ensure ``meaningful and timely input
by State and local officials in the development of regulatory policies
that have federalism implications.'' ``Policies
[[Page 70191]]
that have federalism implications'' is defined in the Executive Order
to include regulations that have ``substantial direct effects on the
States, on the relationship between the national government and the
States, or on the distribution of power and responsibilities among the
various levels of government.'' This final rule directly regulates
growers, food processors, food handlers and food retailers, not States.
This action does not alter the relationships or distribution of power
and responsibilities established by Congress in the preemption
provisions of FFDCA section 408(n)(4).
IX. Submission to Congress and the General Accounting Office
The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and to the Comptroller General of the
United States. EPA will submit a report containing this rule and other
required information to the U.S. Senate, the U.S. House of
Representatives, and the Comptroller General of the United States prior
to publication of this final rule in the Federal Register. This final
rule is not a ``major rule'' as defined by 5 U.S.C. 804(2).
List of Subjects in 40 CFR Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.
Dated: December 1, 1999.
James Jones,
Director, Registration Division, Office of Pesticide Programs.
Therefore, 40 CFR chapter I is amended as follows:
PART 180--[AMENDED]
1. The authority citation for part 180 continues to read as
follows:
Authority: 21 U.S.C. 321(q), 346(a) and 371.
2. By revising Sec. 180.428, to read as follows:
Sec. 180.428 Metsulfuron methyl; tolerances for residues.
(a) General. (1) Tolerances are established for the combined
residues of the herbicide metsulfuron methyl (methyl 2-[[[[(4-methoxy-
6-methyl-1,3,5-triazin-2-yl)amino]
carbonyl]amino]sulfonyl]benzoate) and its metabolite methyl 2-[[[[(4-
methoxy-6-methyl-1-,3,5-triazin-2-yl)amino]carbonyl]amino] sulfonyl]-4-
hydroxybenzoate in or on the following raw material agricultural
commodities:
------------------------------------------------------------------------
Parts
Commodity per
million
------------------------------------------------------------------------
Barley, grain.................................................. 0.1
Barley, hay.................................................... 20.0
Barley, straw.................................................. 0.3
Grass, fodder.................................................. 15.0
Grass, forage.................................................. 15.0
Grass, hay..................................................... 15.0
Sugarcane...................................................... 0.05
Wheat, grain................................................... 0.1
Wheat, green forage............................................ 5.0
Wheat, hay..................................................... 20.0
Wheat, straw................................................... 0.3
------------------------------------------------------------------------
(2) Tolerances are established for residues of metsulfuron methyl
(methyl-2[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)
amino]carbonyl] amino]sulfonyl]benzoate) in or on the following raw
agricultural commodities:
------------------------------------------------------------------------
Parts
Commodity per
million
------------------------------------------------------------------------
Cattle, fat.................................................... 0.1
Cattle, kidney................................................. 0.5
Cattle, meat................................................... 0.1
Cattle, meat byproduct......................................... 0.1
Goats, fat..................................................... 0.1
Goats, kidney.................................................. 0.5
Goats, meat.................................................... 0.1
Goats, meat byproduct.......................................... 0.1
Hogs, fat...................................................... 0.1
Hogs, kidney................................................... 0.5
Hogs, meat..................................................... 0.1
Hogs, meat byproduct........................................... 0.1
Horses, fat.................................................... 0.1
Horses, kidney................................................. 0.5
Horses, meat................................................... 0.1
Horses, meat byproduct......................................... 0.1
Milk........................................................... 0.05
Sheep, fat..................................................... 0.1
Sheep, kidney.................................................. 0.5
Sheep, meat.................................................... 0.1
Sheep, meat byproduct.......................................... 0.1
------------------------------------------------------------------------
(b) Section 18 emergency exemptions. Time-limited tolerances are
established for the combined residues of the herbicide metsulfuron
methyl and its 4-hydroxy metabolite (methyl 2-[[[[(4-methoxy-6-methyl-
1,3,5-triazin-2-yl) amino]carbonyl]-amino] sulfonyl]-4-
hydroxybenzoate)] in connection with use of the pesticide under section
18 emergency exemptions granted by EPA. The tolerances will expire and
are revoked on the dates specified in the following table.
------------------------------------------------------------------------
Expiration/
Commodity Parts per Revocation
million Date
------------------------------------------------------------------------
Sorghum, fodder............................... 0.5 12/31/01
Sorghum, forage............................... 0.3 12/31/01
Sorghum, grain................................ 0.4 12/31/01
------------------------------------------------------------------------
(c) Tolerances with regional registrations. [Reserved]
(d) Indirect or inadvertent residues. [Reserved]
[FR Doc. 99-32652 Filed 12-15-99; 8:45 am]
BILLING CODE 6560-50-F
