[Federal Register Volume 61, Number 123 (Tuesday, June 25, 1996)]
[Notices]
[Pages 32799-32801]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-16128]



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ENVIRONMENTAL PROTECTION AGENCY
[FRL-5526-6]


Proposed Process for Reevaluating Cancer Assessments

AGENCY: U.S. Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: On April 23, 1996, EPA issued a proposal to revise its 1986 
Guidelines for Cancer Risk Assessment (61 FR 17960). Today, EPA is 
proposing a process for using the new guidelines to reevaluate cancer 
hazard and dose-response assessments developed using the 1986 
guidelines.
    EPA is inviting public comment on its proposal to identify, 
prioritize and select agents for reevaluation. This proposal outlines 
opportunities for public involvement in the reevaluation process, and 
requests comment on the proposed process. The new process would take 
effect when the Proposed Guidelines are issued as final.
    In addition, this notice also discusses the use of the Proposed 
Guidelines in ongoing or new cancer assessments.

DATES: Comments on this proposal must be submitted on or before 
September 23, 1996.

ADDRESSES: This notice contains the full proposed process for 
reevaluating cancer assessments.
    Submitting Comments: Comments on the proposed process should be 
submitted to: U.S. Environmental Protection Agency, Air and Radiation 
Docket and Information Center (6102), Attn: File CAN-96-01, Waterside 
Mall, 401 M St. SW, Washington, DC 20460. Please submit one unbound 
original with pages numbered consecutively, and three copies. For 
attachments, provide an index, number pages consecutively, provide 
comment on how the attachments relate to the main comment(s), and 
submit an unbound original and three copies. Please identify all 
comments and attachments with the file number CAN-96-01. Mailed 
comments must be postmarked by the date indicated. Comments may be also 
submitted electronically by sending electronic mail (e-mail) to: A-and-
R-D[email protected]. Electronic comments must be submitted as an 
ASCII file avoiding the use of special characters and any form of 
encryption. Comments and data will also be accepted on disks in 
WordPerfect 5.1 file format or ASCII file format. All comments in 
electronic form must also be identified by the file number CAN-96-01. 
No Confidential Business Information (CBI) should be submitted through 
e-mail.
    The docket and information center is open for public inspection and 
copying between 8:00 a.m. and 5:30 p.m., weekdays, at the Air and 
Radiation Docket and Information Center (6102), Room M-1500, 401 M St. 
SW, Washington, DC 20460. The docket and information center is located 
on the ground floor of Waterside Mall. The file index, materials and 
comments are available for review in the information

[[Page 32800]]

center or copies may be mailed on request from the Air and Radiation 
Docket and Information Center by calling (202) 260-7548 or -7549. The 
FAX number for the Center is (202) 260-4400. A reasonable fee may be 
charged for copying information materials.
    Please note that all technical comments received in response to 
this notice will be placed in the public record. For that reason, 
commentors should not submit personal information such as medical data 
or home addresses, confidential business information or information 
protected by copyright. Due to limited resources, acknowledgments will 
not be sent.

Requesting Copies of Proposed Guidelines

    To obtain a copy of the Proposed Guidelines for Carcinogen Risk 
Assessment (61 FR 17960), interested parties should consult the April 
23 Federal Register notice or contact ORD Publications, Technology 
Transfer and Support Division, National Risk Management Research 
Laboratory, U.S. Environmental Protection Agency, 26 W. Martin Luther 
King Drive, Cincinnati, OH 45268; telephone: 513-569-7566. Please 
provide your name, mailing address, document title (Proposed Guidelines 
for Carcinogen Risk Assessment), and EPA number (EPA/600/P-92/003C).

FOR FURTHER INFORMATION ON TODAY'S NOTICE CONTACT: Jennifer Orme-
Zavaleta, Office of Water, Telephone Number (202) 260-7571.

Proposed Implementation Strategy for Reevaluating Existing Assessments 
Using the Final Revised Guidelines

Background

    EPA has applied the 1986 Guidelines for Carcinogen Risk Assessment 
to hundreds of environmental agents. The results of many of these 
cancer hazard and dose-response assessments (hereafter referred to as 
assessments) can be found on EPA's Agency-wide Integrated Risk 
Information System (IRIS) database. Other assessments are maintained 
separately within individual EPA programs (e.g., certain pesticides). 
Information on IRIS and the other assessments are used as guidance to 
support Agency decisions.
    Once the Proposed Guidelines are finalized, EPA will continue to 
rely on existing assessments as they are still viewed as scientifically 
acceptable based on the 1986 Guidelines. However, EPA recognizes that 
under some circumstances, it will be appropriate to reassess an 
existing assessment taking into account new risk assessment methods, 
principles and data. As EPA's current compendium of cancer assessments 
is the product of many years of analysis, it is reasonable to assume 
that revisiting all existing assessments could require comparable 
amounts of time and resources. Therefore, it would not be practicable 
to reassess all these existing assessments and balance our commitment 
to assess new agents as well. Given these circumstances, EPA is 
proposing a process for applying the revised Cancer Guidelines that 
moves the Agency forward with new assessments, while also addressing 
reassessments of some environmental agents.

Proposed Reassessment Process

    EPA proposes the following process to involve the public in the 
identification, prioritization and selection of candidate environmental 
agents for reevaluation. The intent is to ensure that agents that 
warrant reevaluation are given the highest priority.
    EPA envisions the following process:
    (1) EPA publishes an annual notice in the Federal Register 
requesting candidates for reevaluation,
    (2) Candidates are submitted,
    (3) Candidates are reviewed and prioritized within the Agency,
    (4) Candidates selected are published in a Federal Register notice. 
Submitters are notified on the status of their submission.
    (5) Reassessment is initiated in the next fiscal year. The 
reassessment is reviewed in accordance with EPA's Peer Review Policy 
and placed on IRIS.
    In selecting candidates for reevaluation, EPA will consider the 
following:
    (1) whether application of the new guidelines will appreciably 
change the existing cancer assessment,
    (2) completeness and validity of the scientific information,
    (3) EPA priorities,
    (4) Resources.

Discussion

    On an annual basis, EPA will publish in the Federal Register a list 
of agents for which EPA plans to initiate cancer hazard and dose 
response assessments in the following year. A rationale will be given. 
This list may include reassessments as well as new assessments to meet 
Agency needs, focusing on evidence that application of the new 
guidelines is expected to change the assessment.
Call for Candidates and Screening Criterion
    In addition, the above notice will ask the public for candidates 
for reassessment. For all nominations, EPA will ask the public to 
provide evidence that application of the revised guidelines is likely 
to appreciably change the existing cancer assessment. This requirement 
represents the criterion that the Agency will use to screen candidates 
for reassessment. Along with this nomination, EPA will encourage the 
public to propose a revised cancer assessment which applies the revised 
guidelines; this could greatly facilitate the review for selection. If 
an interested party is not able to provide a revised assessment, then 
the nomination should be accompanied by a justification explaining the 
importance of reassessing that agent. Candidates for reassessment will 
be accepted during a 90-day period.
Prioritization and Peer Review
    An Agency screening team will review all nominations. The team will 
first determine if the above criterion is met. Then, the screening team 
will prioritize the submissions based on completeness and quality of 
the supporting information and consistency with Agency priorities. It 
is the intent of the Agency to involve peer review of the scientific 
validity and relative ranking of the candidates proposed for 
reassessment. The peer review can assist EPA in the final 
prioritization of requests for reevaluation. A number of peer review 
mechanisms can be used, including the Science Advisory Board, an 
annually constituted expert panel specifically charged with reviewing 
the ranking of chemicals, targeted mail reviews to expert independent 
reviewers, or other peer review mechanisms.
    (a) Completeness and scientific validity of the supporting 
information: The screening team will consider the extent to which a 
request for reevaluation is supported by a complete reassessment or 
justification. A complete, high-quality reassessment should address all 
the principles of the new Guidelines.
    EPA expects that commentors may be interested in submitting 
candidates based on minor changes, e.g., change in interspecies scaling 
factor. Revising risk assessments based on minor changes may or may not 
be consistent with Agency priorities. Thus, commentors are encouraged 
to apply all elements of the Guidelines in their supporting materials.
    (b) Agency priorities: Following review of the screening criterion 
and supporting scientific information, the Agency screening team will 
weigh the list of candidates according to the following Agency 
priorities:


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Degree of public health protection,
Protecting the maximum number of people including sensitive subgroups,
Addressing the public interest,
Addressing multimedia exposure,
Addressing agents where there is scientific controversy,
Addressing the potential to change a regulation.

    Prioritization of candidates will be case-by-case depending on 
issues identified above. The screening team may give higher priority to 
those agents for which public health protection is of concern to ensure 
that those agents with the potentially highest risk are addressed 
first. Other factors such as potential for widespread exposure, 
particularly to sensitive members of the population, may also place an 
agent higher on the list.
Selection and Notification
    Once the candidate list has been prioritized, the Agency will 
evaluate the availability of resources for final selection of 
candidates for reassessment. The Agency must balance resource needs for 
new assessments as well as reassessments in making this decision. 
Resources include the availability of staff time as well as resources 
for conducting peer reviews.
    In the fourth quarter of each fiscal year, EPA will publish in the 
Federal Register a list of agents that have been selected for 
reevaluation. Those who submitted comments will be notified in writing. 
If a chemical is not selected for reassessment in the upcoming cycle, 
EPA will explain its reasons for not including the requester's 
candidate and invite the requester to resubmit its request during the 
next cycle (with any updated supporting information, if desired or 
necessary). A decision to not include a chemical in any given cycle 
does not mean that the Agency does not consider reassessment of the 
chemical to be appropriate, and it certainly does not mean that the 
Agency will not reassess the chemical in some later cycle. The decision 
merely means that given Agency resources for the performance of 
reassessments in the upcoming cycle and the other candidates presented, 
the Agency will not be able to reassess the requestor's candidate in 
the next cycle. For purposes of judicial review, the Agency does not 
consider this prioritization decision to be a final Agency action on a 
request to reassess a chemical.
    Once an assessment (including reevaluations) has been completed by 
EPA, it will undergo peer review in accordance with the Agency's Peer 
Review Policy. Consistent with previous practices for conducting 
assessments, EPA may also consult with other Federal agencies. The 
final reassessment, reflecting Agency consensus and peer review, will 
be summarized in IRIS.
    The Office of Pesticide Programs is conducting new or updated 
cancer assessments on certain pesticides according to timetables 
established for its reregistration, registration and special review 
programs. A list of potential candidate chemicals to be evaluated in 
reregistration during FY97 was published for comment in the Federal 
Register on May 15, 1996. The comment period for that notice ends July 
15, 1996. Therefore, requests to reevaluate previous assessments 
associated with the listed pesticides are not necessary under the 
process outlined above.

Issues for Comment

    EPA requests comments on the proposed process for reevaluating 
existing cancer hazard and dose response assessments. Specifically, EPA 
seeks public opinion on four topics.
    (1) The screening criterion.
    (2) The relative importance of the different prioritization factors 
in determining where an agent falls on the list. Other factors that can 
usefully be considered.
    (3) The utility and appropriateness of the peer review mechanism(s) 
suggested for peer review of the ranking of chemicals for reevaluation. 
Please note that peer review of each completed EPA assessment (both new 
and reevaluated) will proceed as outlined above.
    (4) Other relevant issues pertaining to this proposed process.

Interim Use of the Proposed Guidelines Pending Finalization in New 
Assessments

    EPA will continue in most circumstances to rely on the assessment 
information currently available on IRIS as guidance for use in 
regulatory and non-regulatory decisions. Existing assessments which 
applied the 1986 Guidelines continue to be scientifically acceptable.
    At the same time, the Agency's 1986 Guidelines for Carcinogen Risk 
Assessment provide for use of data on mode(s)/mechanism(s) of action 
and biologically-based models whenever such information is available. 
The 1986 Guidelines state that they are intended to accommodate new 
knowledge and methods regarding cancer assessment as they emerge. 
Accordingly, EPA has used new approaches to cancer assessment for 
agents (such as in EPA's pending reevaluation of dioxin risks) when 
there has been sufficient scientific foundation to support the new 
approaches.
    Thus, pending publication of the final revised guidelines and in 
keeping with advancing knowledge on cancer assessment, the principles 
and approaches of the Proposed Guidelines will be applied in part or in 
whole, on a case-by-case basis for new assessments as data warrant. 
Such use of the Proposed Guidelines will allow EPA to gain more 
experience before they are finalized. The assessment will state the 
rationale for applying the Proposed Guidelines. When the Guidelines are 
adopted by the Agency as final, they will provide guidance for all new 
cancer hazard and dose-response assessments. EPA will continue to use 
appropriate peer review processes during this time.
    In summary, EPA recognizes the possible need to reevaluate cancer 
assessments developed using the 1986 Guidelines for Carcinogen Risk 
Assessment. In addition, EPA must also address new chemicals to meet 
Agency priorities. Thus, EPA is proposing a process that will enable it 
to move forward in conducting new assessments while also reevaluating 
existing assessments using the new guidelines.

    Dated: June 17, 1996.
Henry L. Longest,
Acting Assistant Administrator for Research and Development.
[FR Doc. 96-16128 Filed 6-24-96; 8:45 am]
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