[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: [email protected].
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 [email protected], 
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: [email protected]. 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