[Federal Register Volume 67, Number 181 (Wednesday, September 18, 2002)]
[Notices]
[Pages 58797-58799]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-23594]


-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

[OPP-2002-0192; FRL-7197-9]


Diquat Dibromide; Notice of Availability of Decision on 
Syngenta's Request to Modify Label Requirements and Closure of 1995 RED

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

-----------------------------------------------------------------------

SUMMARY:  This notice announces EPA's intention to modify certain 
occupational and residential risk mitigation measures that were imposed 
as a result of the 1995 Reregistration Eligibility Decision (RED) for 
diquat dibromide. At the end of the comment period, the Agency will 
consider this action an immediate final decision and the 1995 RED 
closed, unless adverse comments are received. The Agency conducted this 
reassessment in response to new data submitted by the technical 
registrant, Syngenta Crop Protection, Inc. Syngenta has requested the 
Agency modify certain diquat dibromide label requirements including: 
Personal protective equipment (PPE), closed loading system for aerial 
applications, reentry intervals, and allow residential broadcast spray 
uses.

DATES: Comments, identified by docket identification (ID) number OPP-
2002-0192, must be received on or before October 18, 2002.

ADDRESSES: Comments may be submitted by mail, electronically, or in 
person. Please follow the detailed instructions for each method as 
provided in Unit I. of the SUPPLEMENTARY INFORMATION. To ensure proper 
receipt by EPA, it is imperative that you identify docket ID number 
OPP-2002-0192 in the subject line on the first page of your response.

FOR FURTHER INFORMATION CONTACT:  Tyler Lane, Special Review and 
Reregistration Division (7508C), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460; telephone number: (703) 305-2737; 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, nevertheless, a 
wide range of stakeholders will be interested in obtaining information 
on the label adjustments for diquat dibromide, including environmental, 
human health, and agricultural advocates; the chemical industry; 
pesticide users; and members of the public interested in the use of 
pesticides on food. Since other entities also may 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.

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/. 
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/. Copies of the tolerance reassessment decision and supporting 
risk assessment documents for the reregistration of diquat dibromide 
may also be accessed at http://www.epa.gov/pesticides/reregistration/diquat_dibromide.htm.
    2. In person. The Agency has established an official record for 
this action under docket ID number OPP-2002-0192. 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.

[[Page 58798]]

C. How and to Whom Do I Submit Comments?

    You may submit comments through the mail, in person, or 
electronically. To ensure proper receipt by EPA, it is imperative that 
you identify docket ID number OPP-2002-0192 in the subject line on the 
first page of your response.
    1. By mail. Submit your comments to: Public Information and Records 
Integrity Branch (PIRIB), Information Resources and Services Division 
(7502C), Office of Pesticide Programs (OPP), Environmental Protection 
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
    2. In person or by courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Information Resources 
and Services Division (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, Rm. 119, Crystal Mall 2, 1921 
Jefferson Davis Highway, Arlington, VA. The PIRIB is open from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.
    3. Electronically. You may submit your comments electronically by 
e-mail to: [email protected], or you can submit a computer disk as 
described above. Do not submit any information electronically that you 
consider to be CBI. Avoid the use of special characters and any form of 
encryption. Electronic submissions will be accepted in WordPerfect 6.1/
8.0/9.0 or ASCII file format. All comments in electronic form must be 
identified by docket ID number OPP-2002-0192. Electronic comments may 
also be filed online at many Federal Depository Libraries.

D. How Should I Handle CBI That I Want to Submit to the Agency?

    Do not submit any information electronically that you consider to 
be CBI. You may claim information that you submit to EPA in response to 
this document as CBI 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. In addition to one complete 
version of the comment that includes any information claimed as CBI, a 
copy of the comment that does not contain the information claimed as 
CBI must be submitted for inclusion in the public version of the 
official record. Information not marked confidential will be included 
in the public version of the official record without prior notice. If 
you have any questions about CBI or the procedures for claiming CBI, 
please consult the person identified under FOR FURTHER INFORMATION 
CONTACT.

E. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide copies of any technical information and/or data you used 
that support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at the estimate that you provide.
    5. Provide specific examples to illustrate your concerns.
    6. Make sure to submit your comments by the deadline in this 
document.
    7. To ensure proper receipt by EPA, be sure to identify the docket 
ID number assigned to this action in the subject line on the first page 
of your response. You may also provide the name, date, and Federal 
Register citation.

II. Background

A. What Action is the Agency Taking?

    In 1995, the Agency published its Reregistration Eligibility 
Decision (RED) for diquat dibromide. Subsequent to the publication of 
the 1995 RED, the technical registrant submitted additional data to 
further refine diquat dibromide worker exposure and residential 
broadcast spray use scenarios.
    Changes to the PPE label requirements of the 1995 RED are based on 
the submission of additional data from a biomonitoring study of 
knapsack applications of the closely related chemical paraquat, and a 
reconsideration of the acute dermal toxicity endpoint. The Agency 
reevaluated the dermal toxicity endpoint and rendered a decision that 
the repeated dose dermal toxicity study used for the 1995 RED was not 
appropriate for use in the risk assessment because the skins of the 
rats used in the study were compromised. Instead, the Agency 
extrapolated a dermal toxicity endpoint from a short-term oral study on 
rabbits.
    The Agency has also reevaluated dermal absorption assumptions. 
Previously, EPA assumed a standard absorption rate of 4.1%, based on a 
rat dermal absorption study. Syngenta cited a human dermal absorption 
study estimating a 0.3% dermal absorption rate for diquat dibromide 
(Feldman RJ and Maibach HI, ``Percutaneous penetration of some 
pesticides and herbicides in man'' Tox. Appl. Pharm. 28 126-132, 1974). 
The Agency has relied on data provided by the Feldman-Maibach study for 
previous risk assessments, and believes the study to be acceptable and 
the data valid for use in this risk assessment. The use of the dermal 
absorption factor of 0.3% further refines all aggregate margins of 
exposure (MOEs) above the target MOE of 100, which would not be of 
concern to the Agency.
    The Agency has evaluated the request to modify the cited label 
requirements and summarized its assessment in the Occupational Risk 
Evaluation: ``Assessing Syngenta's Request to Modify Diquat Dibromide 
Label Requirements,'' dated February 14, 2002. In addition, the ``HED 
Risk Assessment for Tolerance Reassessment Eligibility Document 
(TRED),'' March 6, 2002, and the ``Re-characterization of Risk for the 
Diquat Dibromide Tolerance Reassessment Eligibility Decision (TRED) 
Based on New Dermal Absorption Data,'' March 13, 2002, were used to aid 
in the assessment of aggregate risks from residential uses. Any 
labeling changes are presented in the ``Required Labeling Changes 
Summary Table,'' which summarizes the labeling requirements for this 
action. All supporting documents referenced in this document are 
available in the public docket and at http://www.epa.gov/pesticides/reregistration/diquat_dibromide.htm.
    In summary, the Agency expects to change the label requirements of 
the 1995 RED for worker PPE and residential broadcast spray uses. The 
following table presents the 1995 RED decisions being reevaluated, the 
requests to change these requirements made by Syngenta, and the current 
Agency decisions to amend the 1995 RED:

[[Page 58799]]



------------------------------------------------------------------------
                                                      Amendments to 1995
          July 1995 RED            Syngenta Request           RED
------------------------------------------------------------------------
All workers required to wear a    Reduced PPE         All workers must
 double layer of clothing          requirements due    continue to wear
 (coveralls over long sleeved      potential for       protective
 shirt, long pants), chemical      heat stress to      footwear and
 resistant gloves, chemical        field workers and   coveralls over a
 resistant footwear plus socks,    applicators         single layer of
 chemical resistant headgear for                       clothes (products
 overhead exposure, and a                              with a dermal
 chemical resistant apron when                         toxicity of III
 cleaning equipment, mixing or                         or IV may reduce
 loading)                                              PPE to protective
                                                       footwear and
                                                       coveralls over
                                                       short pants and
                                                       short sleeve
                                                       shirts). Mixers,
                                                       loaders and hand
                                                       applicators must
                                                       wear chemical
                                                       resistant gloves,
                                                       while applicators
                                                       who are operating
                                                       closed cab
                                                       equipment are not
                                                       required to wear
                                                       chemical
                                                       resistant gloves
                                                       due to MOEs over
                                                       1,000.
------------------------------------------------------------------------
Respirators for mixing and        No respirator       Respirator
 loading                           requirements for    requirement for
                                   mixing and          mixer/loaders
                                   loading due to      reduced to a face
                                   potential for       shield to prevent
                                   heat stress         droplets from
                                                       entering the
                                                       eyes, mouth or
                                                       nose areas
------------------------------------------------------------------------
Closed mixing system for aerial   Open mixing system  Closed mixing/
 applications.                     for aerial          loading
                                   applications.       requirements
                                                       remain for aerial
                                                       applications.
------------------------------------------------------------------------
7-Day restricted entry interval   4-Hour REI for      REI reduced to 24
 (REI) for products used under     potato              hours for all WPS
 the Worker Protection Standard    desiccation and     uses, based on
 (WPS) unless there is no          seed crops          default reentry
 contact with treated surfaces                         analysis findings
 (such as mechanical harvesting)                       of MOEs between
                                                       150 and 1,500 and
                                                       a toxicity
                                                       category II for
                                                       eye irritation
------------------------------------------------------------------------
4-Day REI for non-WPS uses other  REI when spray is   REI reduced to
 than aquatic and spot treatment   dry for non-WPS     ``when sprays are
 at residential sites              uses                dry'' for non-WPS
                                                       uses, also based
                                                       on default
                                                       reentry analysis
------------------------------------------------------------------------
Prohibition of broadcast spray    Broadcast spray     Generic data
 applications for homeowner and    applications for    requirements have
 residential uses                  homeowner and       been fulfilled
                                   residential uses    for residential
                                                       broadcast spray
                                                       uses. Broadcast
                                                       spray
                                                       applications for
                                                       homeowner and
                                                       residential uses
                                                       for end-use
                                                       products will be
                                                       decided on a case-
                                                       by-case basis
                                                       upon review of
                                                       end-use product
                                                       toxicity, based
                                                       on short-term
                                                       exposure and
                                                       individual risk
                                                       assessments.
------------------------------------------------------------------------

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

    The legal authority for this decision falls under FIFRA, as amended 
in 1988 and 1996. Section 4(g)(2)(A) of FIFRA directs that, after 
submission of all data concerning a pesticide active ingredient, ``the 
Administrator shall determine whether pesticides containing such active 
ingredient are eligible for reregistration,'' and either reregister 
products or take other ``appropriate regulatory action.''

List of Subjects

    Environmental protection, Chemicals, Aquatic herbicides.

    Dated: September 5, 2002.
Lois Rossi,
Director, Special Review and Reregistration Division, Office of 
Pesticide Programs.
[FR Doc. 02-23594 Filed 9-17-02; 8:45 am]
BILLING CODE 6560-50-S