UNfTED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON D.C. 20460
October 29, 1992
OFFICE OF
I1« ADMINISTRATOR
SCJENCE ADVISORY BOARD
EPA-SAB-IAQC-LTR-93-OG2
Honorable William K. Eeilly
Administrator
U.S. Environmental Protection Agency
401 M Street, SW
Washington, DC 20460
Subject; Science Advisory Board Review of the Risk Assessment
Forum's Draft Guidance Document on Showering with
VOC Contaminated Tap Water
Dear Mr. Reilly;
On February 24-2S, 1992, the Indoor Air Quality and Total Human
Exposure Committee (IAQTHBC) of the Science Advisory Board met to review the
Office of Research and Development's (ORD) proposed guidance on showering with
tap water contaminated with volatile organic compounds (VOC) (entitled; Project
Summary - Guidance on Estimating Exposure to VOC's During Showering).
According to the Risk Assessment Forum (RAF), this "...document is based on
discussions among EPA scientists and a few outside experts with the goal of
developing some limited guidance for situations where guidance does not currently
exist...." The RAF has developed this guidance for Agency-wide use, and plans on
distributing this guidance through the Agency's Risk Assessment Council.
However, before doing so, the Forum has requested that the SAB review its
interpretation of the underlying science upon which the guidance is based (i.e., is
the guidance scientifically defensible), and whether the recommendations represent
useful, practical guidance for Agency risk assessors.
The Committee has provided the Agency with a detailed discussion of then-
concerns during the public meeting (for which a transcript has been made
available), The Committee has highlighted several of their concerns in this letter,
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including some comments specific to this draft guidance document, as well as
comments which concern the preparation of such guidance documents in general.
Although the Conunittee believes that the draft document represents a good
start towards developing guidance to be used by Regional EPA risk assessors in
responding to public concerns, we believe the draft still needs significant
improvement. We are aware that the scientific basis for anything but general
advice in this case is extremely limited. As with many public health concerns,
vague generic advice may be misleading and inappropriate for many specific
situations that arise. Nevertheless, we were pleased to note that the Agency seeks
to include non-ingestion exposure pathways when assessing risk to VOC, which,
under certain circumstances, can dominate total human exposure. Guidance to
help identify the circumstances where, for example, the inhalation hazard from
volatilized agents can exceed the ingestion hazard is clearly needed by risk
assessors. In addition, there are many factors that affect the total dose of VOC
received from showering, including water temperature, droplet size, room size,
shower duration, and number of showers per day. The latter could be important
considerations for teenagers, and other segments of the population.
We believe that there is also a need to provide easily accessible information
to other public officials and the public who are also concerned about such
instances. Since local health department staff, e.g., local health officers,
sanitarians, and sanitary engineers, often have to (perhaps more often than EPA
regional staff) respond to such concerns, we recommend that EPA consider such
individuals as this guidance document is revised. Ultimatelyj EPA should consider
distributing the guidance to local health departments. We believe that it is not
only important that the various EPA regions give consistent advice, but that the
advice by EPA in a given region is consistent with that given by the local health
departments.
If the Agency chooses to request additional SAB review of guidance
documents such as this one in the future, we would suggest several generic
improvements in addition to the above comments. Clearly, one is a consistent
guidance document format with a standardized outline.
This particular document needs to be presented in a more polished form, so
that it can be reviewed for content and the appropriate use of the scientific
support for the recommendations and guideline steps that are included.
Furthermore, a history of the project and details concerning workshops that
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formed the basis of the information contained in the guidance are extraneous to
the guidance document and can be deleted.
We also recommend that some mechanism be set up to document phone
calls from citkens and to detail the facts of specific incidents and the lessons they
provide. By so doing, regions can share information, providing a timely and
informal mechanism for assessors in the various regions to develop consistent
advice. It would also be a mechanism for use by EPA Headquarters in
determining the effectiveness of these documents in establisMng consistent advice
across the Eegions.
The Committee is not prepared to endorse this draft document as final EPA
guidance at this time. If the Agency chooses to request SAB review of a revised
document in the future, we would are prepared to do so. We appreciate the
opportunily to review this draft document and look forward to your written
response.
Sincerely,
Dr. Raymond C. Loehr, Chair Dr. Morton Lippmann, Chair
Executive Committee Indoor Air Quality and Total
Science Advisory Board Human Exposure Committee
Science Advisory Board
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UJEL Environmental Protection Agency
Science Advisory Board
Indoor Air Quality and Total Human Exposure Committee
Chairman
Dr. Morton Lippmann, Institute of Environmental Medicine, New York University
Medical Center, Tuxedo, NY
Dr. Jan A* J. Stolwgk, School of Medicine, Department of Epidemiology and Public
Health, Yale University, New Haven, CT
Members
Dr. Joan Daisey, Indoor Environment Program, Lawrence Berkeley Laboratory,
Berkeley, CA
Dr. Timothy Larson, University of Washington, Seattle, WA
Dr. Victor G, Laties, University of Rochester Medical Center, Rochester, NY
Dr. Paul Lioy, Department of Environmental and Community Medicine, Robert Wood
Johnson School of Medicine, Piscataway, NJ
Dr. Jonathan M. Samet, New Mexico Tumor Registry, Albuquerque, NM
Dr. Jerome J. WesolowsM, Air and Industrial Hygiene Lab., California Department
of Health, Berkeley, CA
Dr. James E. Woods, Jr., College of Architecture and Urban Studies, Viginia Tech
Blacksburg, VA
Science Advisory Board Staff
Mr, A. Robert Flaak, Assistant Director, Science Advisory Board, U.S. EPA,
Washington, DC
Ms. Carolyn Qsborae, Program Assistant, Science Advisory Board, U.S, EPA,
Washington, DC
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NOTICE
This report has been written as a part of the activities of the Science Advisory
Board, a public advisory group providing extramural scientific information and
advice to the Administrator and other officials of the Environmental Protection
Agency. The Board is structured to provide balanced, expert assessment of
scientific matters related to problems facing the Agency. This report has not been
reviewed for approval by the Agency and, hence, the contents of this report do not
necessarily represent the views and policies of the Environmental Protection
Agency, nor of other agencies in the Executive Branch of the Federal government,
nor does mention of trade names or commercial products constitute a
recommendation for use.
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