Setting Priorities for Drinking Water Contaminants

Committee on Drinking Water Contaminants

Water Science and Technology Board

Board on Environmental Studies and Toxicology

Commission on Geosciences, Environment, and Resources

NATIONAL ACADEMY PRESS
Washington, D.C.
1999



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page R1
--> Setting Priorities for Drinking Water Contaminants Committee on Drinking Water Contaminants Water Science and Technology Board Board on Environmental Studies and Toxicology Commission on Geosciences, Environment, and Resources NATIONAL ACADEMY PRESS Washington, D.C. 1999

OCR for page R1
--> NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. Support for this project was provided by the Environmental Protection Agency under contract no. X-826345-01-0. Library of Congress Catalog Card Number 98-88191 International Standard Book Number 0-309-06293-4 Additional copies of this report are available from: National Academy Press 2101 Constitution Avenue, NW Box 285 Washington, D.C. 20055 800-624-6242 202-334-3313 (in the Washington metropolitan area) http://www.nap.edu Copyright 1999 by the National Academy of Sciences. All rights reserved. Printed in the United States of America

OCR for page R1
--> COMMITTEE ON DRINKING WATER CONTAMINANTS WARREN R. MUIR, Chair, Hampshire Research Institute, Alexandria, Virginia R. RHODES TRUSSELL, Vice-Chair, Montgomery Watson, Inc., Pasadena, California FRANK J. BOVE, Agency for Toxic Substances and Disease Registry, Atlanta, Georgia LAWRENCE J. FISCHER, Michigan State University, East Lansing WALTER GIGER, Swiss Federal Institute of Environmental Science and Technology, Zurich BRANDEN B. JOHNSON, New Jersey Department of Environmental Protection, Trenton NANCY K. KIM, Center for Environmental Health, Albany, New York MICHAEL J. MCGUIRE, McGuire Environmental Consultants, Santa Monica, California DAVID M. OZONOFF, Boston University, Massachusetts CATHERINE A. PETERS, Princeton University, New Jersey JOAN B. ROSE, University of South Florida, St. Petersburg PHILIP C. SINGER, University of North Carolina, Chapel Hill DEBORAH L. SWACKHAMER, University of Minnesota, Minneapolis PAUL G. TRATNYEK, Oregon Graduate Institute of Science and Technology, Portland Staff JACQUELINE A. MACDONALD, Study Director CAROL A. MACZKA, Director, BEST Toxicology and Risk Assessment Program MARK C. GIBSON, Research Associate KIMBERLY A. SWARTZ, Project Assistant

OCR for page R1
--> WATER SCIENCE AND TECHNOLOGY BOARD HENRY J. VAUX, JR., Chair, University of California, Riverside CAROL A. JOHNSTON, Vice-Chair, University of Minnesota, Duluth RICHELLE ALLEN-KING, Washington State University, Pullman JOHN S. BOYER, University of Delaware, Lewes JOHN BRISCOE, The World Bank, Washington, D.C. DENISE FORT, University of New Mexico, Albuquerque EVILLE GORHAM, University of Minnesota, St. Paul CHARLES D. D. HOWARD, Charles Howard & Associates, Victoria, British Columbia, Canada WILLIAM A. JURY, University of California, Riverside WILLIAM M. LEWIS, JR., University of Colorado, Boulder GARY S. LOGSDON, Black & Veatch, Cincinnati, Ohio RICHARD G. LUTHY, Carnegie Mellon University, Pittsburgh, Pennsylvania JOHN W. MORRIS, J. W. Morris, Ltd., Arlington, Virginia CHARLES R. O'MELIA, Johns Hopkins University, Baltimore, Maryland PHILIP A. PALMER, DuPont Engineering, Wilmington, Delaware REBECCA T. PARKIN, The George Washington University, Washington, D.C. JOAN B. ROSE, University of South Florida, St. Petersburg ERIC F. WOOD, Princeton University, New Jersey Staff STEPHEN D. PARKER, Director JACQUELINE A. MACDONALD, Associate Director CHRIS ELFRING, Senior Staff Officer LAURA J. EHLERS, Staff Officer JEFFREY W. JACOBS, Staff Officer JEANNE M. AQUILINO, Administrative Associate MARK C. GIBSON, Research Associate ANITA A. HALL, Administrative Assistant ELLEN A. DE GUZMAN, Senior Project Assistant KIMBERLY A. SWARTZ, Project Assistant

OCR for page R1
--> BOARD ON ENVIRONMENTAL STUDIES AND TOXICOLOGY GORDON ORIANS, Chair, University of Washington, Seattle DONALD MATTISON, Vice-Chair, University of Pittsburgh, Pennsylvania DAVID ALLEN, University of Texas, Austin MAY R. BERENBAUM, University of Illinois, Urbana EULA BINGHAM, University of Cincinnati, Ohio PAUL BUSCH, Malcolm Pirnie, Inc., White Plains, New York PETER L. DEFUR, Virginia Commonwealth University, Richmond DAVID L. EATON, University of Washington, Seattle ROBERT A. FROSCH, Harvard University, Cambridge, Massachusetts JOHN GERHART, University of California, Berkeley MARK HARWELL, University of Miami, Florida ROGENE HENDERSON, Lovelace Respiratory Research Institute, Albuquerque, New Mexico CAROL HENRY, American Petroleum Institute, Washington, D.C. BARBARA HULKA, University of North Carolina, Chapel Hill DANIEL KREWSKI, Health Canada and University of Ottawa, Ontario JAMES A. MACMAHON, Utah State University, Logan MARIO J. MOLINA, Massachusetts Institute of Technology, Cambridge WARREN MUIR, Hampshire Research Institute, Alexandria, Virginia CHARLES O'MELIA, Johns Hopkins University, Baltimore, Maryland KIRK SMITH, University of California, Berkeley MARGARET STRAND, Bayh, Connaughton and Malone, Washington, D.C. GERALD N. WOGAN, Massachusetts Institute of Technology, Cambridge TERRY F. YOSIE, Ruder Finn, Inc., Washington, D.C. Staff JAMES J. REISA, Director DAVID J. POLICANSKY, Associate Director and Program Director for Applied Ecology CAROL A. MACZKA, Program Director for Toxicology and Risk Assessment LEE R. PAULSON, Program Director for Resource Management RAYMOND A. WASSEL, Program Director for Environmental Sciences and Engineering KULBIR BAKSHI, Program Director for the Committee on Toxicology

OCR for page R1
--> COMMISSION ON GEOSCIENCES, ENVIRONMENT, AND RESOURCES GEORGE M. HORNBERGER, Chair, University of Virginia, Charlottesville PATRICK R. ATKINS, Aluminum Company of America, Pittsburgh, Pennsylvania JERRY F. FRANKLIN, University of Washington, Seattle B. JOHN GARRICK, PLG, Inc., Newport Beach, California THOMAS E. GRAEDEL, Yale University, New Haven, Connecticut DEBRA KNOPMAN, Progressive Foundation, Washington, D.C. KAI N. LEE, Williams College, Williamstown, Massachusetts JUDITH E. MCDOWELL, Woods Hole Oceanographic Institution, Massachusetts RICHARD A. MESERVE, Covington & Burling, Washington, D.C. HUGH C. MORRIS, Canadian Global Change Program, Delta, British Columbia RAYMOND A. PRICE, Queen's University at Kingston, Ontario H. RONALD PULLIAM, University of Georgia, Athens THOMAS C. SCHELLING, University of Maryland, College Park VICTORIA J. TSCHINKEL, Landers and Parsons, Tallahassee, Florida E-AN ZEN, University of Maryland, College Park MARY LOU ZOBACK, United States Geological Survey, Menlo Park, California Staff ROBERT M. HAMILTON, Executive Director GREGORY H. SYMMES, Assistant Executive Director JEANETTE SPOON, Administrative & Financial Officer SANDI FITZPATRICK, Administrative Associate MARQUITA SMITH, Administrative Assistant/Technology Analyst

OCR for page R1
--> Preface Americans expect to be able to drink the water that comes from their taps without fear for their safety. While this expectation has been largely fulfilled in this century, on occasions and in certain systems, chemicals and microbes still contaminate drinking water supplies in the United States. Thus, continuing vigilance is necessary to assure that important drinking water contaminants are identified and appropriately addressed. In 1996, Congress enacted the Safe Drinking Water Act Amendments of 1996, substantially revising the way in which public water supplies are regulated. Among the amendments is a requirement that the Environmental Protection Agency (EPA) develop a list of currently unregulated contaminants that may pose risks in drinking water. Every five years, EPA must decide whether to regulate at least five of those contaminants and whether to conduct additional monitoring and research for the others. The first of these lists, known as the Drinking Water Contaminant Candidate List (CCL), was published by EPA in March of 1998. EPA has asked the National Research Council (NRC) for assistance in addressing three aspects of this effort: developing a scientifically sound approach for deciding whether or not to regulate contaminants on the current and future CCLs, convening a workshop that will focus on emerging drinking water contaminants and the database that should be created to support future decision making on such contaminants, and creating a scientifically sound approach for developing future CCLs.

OCR for page R1
--> This report, written by the NRC's Committee on Drinking Water Contaminants, addresses the first of these topics. It includes a review of ten different governmental and private schemes used to rank environmental contaminants in other contexts to identify whether, and in what manner, such schemes might apply to the three tasks being addressed by the committee. The committee consists of 14 volunteer experts in water treatment engineering, water chemistry, analytical chemistry, microbiology, toxicology, public health, epidemiology, risk assessment, and risk communication. This report's findings are based on a review of relevant technical literature, information gathered at two committee meetings, and the expertise of committee members. The committee will address the remaining two topics in subsequent reports. On behalf of the committee, I wish to thank Jim Taft, Evelyn Washington, and Chuck Job of EPA for supporting this important three-phased review. In addition, thanks go to William Carpenter, attorney and member of the National Drinking Water Advisory Council's Working Group on Occurrence and Contaminant Selection; Stephen Clark, EPA Office of Ground Water and Drinking Water; and Thomas Yohe, Philadelphia Suburban Water Company. All of these individuals made presentations and supplied valuable background information at the first committee meeting. This report has been reviewed, in accordance with NRC procedures, by individuals chosen for their expertise and broad perspectives on the issues addressed herein. The purpose of this review is to provide independent, candid, and critical comments that will help the NRC to be assured that the report is sound and meets the NRC's standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft report remain confidential to protect the deliberative process by which the report was developed. The committee wishes to thank the following people for their participation in this review and for their many constructive comments: Richard Bull, Washington State University and Battelle Pacific Northwest Laboratory; Gunther Craun, Gunther F. Craun & Associates, Staunton, Virginia; Joseph Delfino, University of Florida; George Hornberger, University of Virginia; Eric Olson, National Resources Defense Council; David Reckhow, University of Massachusetts, Amherst; Robert Spear, University of California, Berkeley; and Thomas Yohe, Philadelphia Suburban Water Company. Notwithstanding this review, however, the final content of this report is the responsibility of the Committee on Drinking Water Contaminants. I speak for the whole committee in thanking the very capable and professional NRC staff for the assistance we have received throughout our deliberations and during report preparation. In particular, I want to acknowledge the outstanding efforts we have received from Jacqueline MacDonald, study director and associate director, Water Science and Technology Board (WSTB),

OCR for page R1
--> Carol Maczka, director of toxicology and risk assessment programs, Board on Environmental Studies and Toxicology, Mark Gibson, research associate, WSTB, and Kimberly Swartz, project assistant, WSTB. These staff members worked extraordinarily hard and effectively to help us produce this report in a very short time, in order to be of maximum utility to EPA as it moves forward to implement the recently enacted drinking water protection mandates. Finally, I want to thank the diverse and talented members of the committee, who were able to bring together their diverse perspectives and broad expertise to produce this report. I look forward to continuing to work with this wonderful group in making a contribution to addressing the second and third phases of our effort. WARREN R. MUIR, Ph.D. CHAIR, COMMITTEE ON DRINKING WATER CONTAMINANTS

OCR for page R1
--> The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. William A. Wulf is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. William A. Wulf are chairman and vice-chairman, respectively, of the National Research Council.

OCR for page R1
--> Contents     Executive Summary   1 1   Introduction   9 2   Review of Existing Chemical Prioritization Schemes   21 3   Review of Methods for Assessing Microbial Pathogens   47 4   Approach Used to Develop the 1998 CCL   57 5   Selecting Contaminants on the CCL for Future Action: Recommended Decision Process   70 Appendix A   Assessing Uncertainty in Decision Processes   103 Appendix B   Biographical Sketches of Committee Members and Staff   109

OCR for page R1
This page in the original is blank.

OCR for page R1
Setting Priorities for Drinking Water Contaminants

OCR for page R1
This page in the original is blank.