[Federal Register Volume 67, Number 147 (Wednesday, July 31, 2002)]
[Notices]
[Pages 49689-49691]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-19105]


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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2002-0156; FRL-7188-5]


Butylate Tolerances are Considered to be Reassessed by EPA

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: This notice announces that EPA is considering as reassessed 
all tolerances for residues of the herbicide butylate. The Agency has 
determined that no common mechanism exists among butylate and the 
thiocarbamates. Therefore, the Agency is not amending its previous 
notice which constituted EPA's report on the Food Quality Protection 
Act (FQPA) of 1996 tolerance reassessment progress and interim risk 
management decision for butylate. By itself, butylate poses no risk 
concerns within the limits of the existing tolerances, which will 
remain in effect at 0.1 part per million (ppm) for all registered 
commodities; however, the Agency intends to revise the commodity 
definitions in accordance with current Agency administrative practice. 
By law, EPA is required by August 2002 to reassess 66% of the 
tolerances in existence on August 2, 1996, or about 6,400 tolerances. 
The regulatory actions in this document pertain to the reassessment of 
seven tolerances which are counted among tolerance/exemption 
reassessments made toward the August 2002 review deadline.

FOR FURTHER INFORMATION CONTACT: By mail: Joseph Nevola, Special Review 
and Reregistration Division (7508C), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460; telephone number: (703) 308-8037; e-mail address: 
[email protected].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    This action is directed to the public in general. This action may, 
however, be of interest to persons who are or may be required to 
conduct testing of chemical substances under the Federal Insecticide, 
Fungicide, and Rodenticide Act (FIFRA) or the Federal Food, Drug, and 
Cosmetic Act (FFDCA); environmental, human health, and agricultural 
advocates; pesticides users; and members of the public interested in 
the use of pesticides. Since other entities may also be interested, the 
Agency has not attempted to describe all the specific entities that may 
be affected by this action. If you have any questions regarding the 
applicability of this action to a particular entity, consult the person 
listed under FOR FURTHER INFORMATION CONTACT.

[[Page 49690]]

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,'' ``Regulations and Proposed Rules,'' 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/.
    To access the butylate TRED (Report on FQPA Tolerance Reassessment 
Progress and Interim Risk Management Decision) and butylate TRED 
support documents electronically, go directly to http://www.epa.gov/pesticides/reregistration/butylate/. You can also go to the EPA Office 
of Pesticide Programs website for Tolerance Reassessment and 
Reregistration, at http://www.epa.gov/pesticides/reregistration/status.htm for additional information on butylate.
    2. In person. The Agency has established an official record for 
this action under docket ID number OPP-2002-0156. 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 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

A. What Action is the Agency Taking?

    This notice announces to the general public that EPA has determined 
that seven tolerances for residues of butylate are considered to be 
reassessed. EPA evaluated existing pesticide tolerances under the FQPA 
of 1996. The butylate tolerances included in this notice have been 
found to meet the FQPA safety standard.
    On September 11, 2001 (66 FR 47219) (FRL-6796-3), EPA published a 
notice in the Federal Register, entitled ``Butylate; Notice of 
Pesticide Report on FQPA Tolerance Reassessment Progress and Interim 
Risk Management Decision.'' That notice constituted the Agency's report 
on the FQPA tolerance reassessment progress and interim risk management 
decision for butylate. At that time, the Agency had not made a full 
reassessment because the cumulative risk from thiocarbamates, such as 
butylate, had not been evaluated. The September 11, 2001, notice 
provided a 30-day comment period and invited public comment for 
consideration. No comments were received by the Agency. Since then, the 
Agency has made a determination on whether two subgroups of the 
pesticides, thiocarbamates and dithiocarbamates, belong to a larger 
group of chemicals known as carbamates and share a common mechanism of 
toxicity. The Agency considered whether they cause a common effect that 
is attributable to a common mechanism. A total of four common effects 
were considered, including acetylcholinesterase inhibition. The Agency, 
guided by several relevant science policies, summarized its position on 
December 19, 2001, with respect to the grouping of the thiocarbamate 
pesticides based on a common mechanism of toxicity and the results of a 
screening level cumulative risk assessment. That December memorandum is 
entitled ``Thiocarbamates: A Determination of the Existence of a Common 
Mechanism of Toxicity and a Screening Level Cumulative Food Risk 
Assessment.'' In that memorandum, EPA announced its determinations 
that:
    1. Some thiocarbamates (EPTC, molinate, pebulate, and cycloate) 
share a common mechanism of toxicity for acetylcholinesterase 
inhibition.
    2. There is insufficient evidence for grouping the thiocarbamate 
pesticides based on a common mechanism for toxicity for effects other 
than acetylcholinesterase inhibition.
    Although, structural and metabolic similarities exist among the 
thiocarbamates and there is evidence that the thiocarbamates may 
produce a common effect (neuropathology), this evidence is insufficient 
to warrant a determination of common mechanism.
    Also, EPA conducted a preliminary screening level cumulative food 
risk assessment for thiocarbamates which incorporated very conservative 
assumptions; i.e., assumptions which overstate significantly the actual 
level of potential risk. While a common mechanism of toxicity could not 
be established for neuropathology, the effect was selected as the 
endpoint for use in a screening level cumulative risk assessment to 
assure that risks would not be underestimated. In part, the Agency 
concluded that given the high dose required to provide evidence of 
neuropathological potential and the questionable significance of the 
solitary finding in a single study conducted with butylate, it is 
unlikely that butylate would contribute to any cumulative dietary risk 
that might result from dietary exposure to two or more thiocarbamates. 
Because the ``No Observed Adverse Effect Level'' (NOAEL) for 
neuropathological effects of butylate is substantially higher (120-
times greater) than the NOAEL used to establish a reference dose (RfD) 
for butylate, and because neuropathology was observed at a limit dose 
(2,000 milligrams/kilograms/day (mg/kg/day), it is unlikely that 
butylate would contribute to potential cumulative risks of the 
thiocarbamates.
    EPA placed the December 19, 2001 memorandum, entitled ``A Common 
Mechanism of Toxicity Determination for Thiocarbamate Pesticides.'' in 
a docket with its attachments. Also, the memorandum is available on the 
Agency's website at http://www.epa.gov/pesticides/cumulative/thiocar.htm. EPA notified its stakeholders of its determination using 
the Pesticide Program Update Messaging System and announced the 
availability of these documents to the media. Further, EPA invited the 
public to submit comments on these determinations during a 60-day 
period, until February 22, 2002. No significant comments were received 
regarding butylate during the provided 60-day period. Therefore, 
chronic cumulative dietary risks for butylate are not of concern to the 
Agency, and all tolerances for butylate in 40 CFR 180.232 for corn, 
field, grain; corn, pop, grain; corn, sweet (kernels, plus cob with 
husk removed); corn, field, stover; corn, field, forage; corn, pop, 
forage; and corn, sweet, forage are now considered fully reassessed 
according to FQPA because aggregate risks were previously assessed (66 
FR 47219) and cumulative risk does not apply. These commodity 
tolerances are each maintained at 0.1 ppm.
    In addition, to conform to current Agency practice, EPA will revise 
specific commodity tolerance definitions in 40 CFR 180.232, according 
to its prior notice of September 11, 2001 (66 FR 47219), in a future 
action that will be published in the Federal Register.

[[Page 49691]]

B. What is the Agency's Authority for Taking this Action?

    The legal authority for tolerance reassessment falls under FFDCA, 
as amended in 1996. Section 408(q) of FFDCA directs that ``the 
Administrator shall review tolerances and exemptions for pesticide 
chemical residues in effect on the day before the date of the enactment 
of the FQPA of 1996, as expeditiously as practicable, assuring that--66 
percent of such tolerances and exemptions are reviewed within 6 years 
(i.e., by August 3, 2002), of the date of enactment of such Act (i.e., 
on August 3, 1996), and--shall determine whether the tolerance or 
exemption meets the requirements of sections 408(b)(2) or (c)(2) and 
shall, by the deadline for the review of the tolerance or exemption, 
issue a regulation under section 408 (d)(4) or (e)(1) to modify or 
revoke the tolerance or exemption if the tolerance or exemption does 
not meet such requirements.'' Under section 408 of the FFDCA, a 
tolerance may only be maintained if EPA determines that the tolerance 
is safe based on a number of factors, including an assessment of the 
aggregate exposure to the pesticide and an assessment of the cumulative 
effects of such pesticide and other substances that have a common 
mechanism of toxicity. In section 408(b)(2) of the FFDCA, ``the term 
`safe,' with respect to a tolerance for a pesticide chemical residue, 
means that the Administrator has determined 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.''

List of Subjects

    Environmental protection. Chemicals, Pesticides and pests, 
thiocarbamate(s).

    Dated: July 19, 2002.
  Lois Ann Rossi,
Director, Special Review and Reregistration Division, Office of 
Pesticide Programs.
[FR Doc. 02-19105 Filed 7-30-02; 8:45 am]
BILLING CODE 6560-50-S