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Suggested Citation:"Front Matter." Transportation Research Board and National Research Council. 2003. Managing Carbon Monoxide Pollution in Meteorological and Topographical Problem Areas. Washington, DC: The National Academies Press. doi: 10.17226/10689.
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Suggested Citation:"Front Matter." Transportation Research Board and National Research Council. 2003. Managing Carbon Monoxide Pollution in Meteorological and Topographical Problem Areas. Washington, DC: The National Academies Press. doi: 10.17226/10689.
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MANAGING CARBON MONOXIDE POLLUTION 1 1~1 IVI ~ I =~J'~> BAJA 1 ~~ AND TOPOGRAPHICAL PROBLEM AREAS Committee on Carbon Monoxide Episodes in Meteorological and Topographical Problem Areas Board on Environmental Studies and Toxicology Board on Atmospheric Sciences and Climate Division on Earth and Life Studies Transportation Research Board NATIONAL RESEARCH COUNCIL OF THE NATIONAL ACADEMIES THE NATIONAL ACADEMIES PRESS Washington, D.C. www.nap.edu

THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, D.C. 20001 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. This project was supported by Contract No. X-82880601-0 between the National Academy of Sciences and the U.S. Environmental Protection Agency. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authoress and do not necessarily reflect the view of the organizations or agencies that provided support for this project. International Standard Book Number 0-309-08923-9 (Book) International Standard Book Number 0-309-50884-3 (PDF) Additional copies of this report are available from: The National Academies Press 500 Fifth Street, NW Box 285 Washington, DC 20055 800-624-6242 202-334-3313 (in the Washington metropolitan area) http://www.nap.edu Copyright 2003 by the National Academy of Sciences. All rights reserved. Printed in the United States of America Cover: photograph by Nick Wheeler/CORBIS

THE NATIONAL ACADEMIES Advisers to the Nation on Science, Engineering, and Medicine 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. Wm. 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. Harvey V. Fineberg 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. Wm. A. Wulf are chair and vice chair, respectively, of the National Research Council. www.natlonal-academles.org

. 6

COMMITTEE ON CARBON MONOXIDE EPISODES IN METEOROLOGICAL AND TOPOGRAPHICAL PROBLEM AREAS Members ARMISTEAD G. RUSSELL (Chair), Georgia Institute of Technology, Atlanta ROGER ATKINSON, University of California, Riverside SUE ANN BOWLING, University of Fairbanks (Retired), Fairbanks, AK STEVEN D. COLOME, University of California, Los Angeles NATHUA DUAN, University of California, Los Angeles GERALD GALLAGHER, J Gallagher and Associates, Inc., Englewood, CO RANDALL L. GUENSEER, Georgia Institute of Technology, Atlanta SUSAN L. HANDY, University of California, Davis SIMONE HOCHGREB, University of Cambridge, England SANDRA N. MOHR, Consultant, Gillette, New Jersey ROGER A. PIEEKE SR., Colorado State University, Fort Collins KARL J. SPRINGER, Southwest Research Institute (Retired), San Antonio, TX ROGER WAYSON, University of Central Florida, Orlando Project Stay K. JOHN HOLMES, Senior Staff Officer RAYMOND WASSEL, Senior Program Director NANCY HUMPHREY, Senior Staff Officer CHAD TOLMAN, Staff Officer LAURIE GELLER, Senior Staff Officer AMANDA STAUDT, Staff Officer KELLY CLARK, Editor MIRSADA KARALIC-LONCAREVIC, Research Assistant RAMYA CHARI, Research Assistant EMILY BRADY, Senior Project Assistant Sponsor U.S. ENVIRONMENTAL PROTECTION AGENCY v

BOARD ON ENVIRONMENTAE STUDIES AND TOXICOEOGY Members GORDON ORIANS (Chair), University of Washington, Seattle JOHN DOULL (Vice Chair9, University of Kansas Medical Center, Kansas City DAVID AEEEN, University of Texas, Austin THOMAS BURKE, Johns Hopkins University, Baltimore, MD JUDITH C. CHOW, Desert Research Institute, Reno, NV CHRISTOPHER B. FIEED, Carnegie Institute of Washington, Stanford, CA WILLIAM H. GLAZE, Oregon Health and Science University, Beaverton SHERR! W. GOODMAN, Center for Naval Analyses, Alexandria, VA DANIEE S. GREENBAUM, Health Effects Institute, Cambridge, MA ROGENE HENDERSON, Lovelace Respiratory Research Institute, Albuquerque, NM CAROL HENRY, American Chemistry Council, Arlington, VA ROBERT HUGGETT, Michigan State University, East Lansing BARRY L. JOHNSON Emory University, Atlanta, GA JAMES H. JOHNSON, Howard University, Washington, DC JAMES A. MACMAHON, Utah State University, Logan PATRICK V. O'BRIEN, Chevron Research and Technology, Richmond, CA DOROTHY E. PATTON, International Life Sciences Institute, Washington, DC ANN POWERS, Pace University School of Law, White Plains, NY LOUISE M. RYAN, Harvard University, Boston, MA JONATHAN M. SAMET, Johns Hopkins University, Baltimore, MD KIRK SMITH, University of California, Berkeley LISA SPEER, Natural Resources Defense Council, New York, NY G. DAVID TILMAN, University of Minnesota, St. Paul CHRIS G. WHIPPLE, Environ Incorporated, Emeryville, CA LAUREN A. ZEISE, California Environmental Protection Agency, Oakland, CA Senior Stay JAMES J. REISA, Director DAVID J. POLICANSKY, Associate Director RAYMOND A. WASSEE, Senior Program Director for Environmental Sciences and Engineering KULBIR BAKSHI, Program Director for the Committee on Toxicology ROBERTA M. WEDGE, Program Director for Risk Analysis K. JOHN HOLMES, Senior Staff Officer SUSAN N.J. MARTEE, Senior Staff Officer SUZANNE VAN DRUNICK, Senior Staff Officer EIEEEN N. ABT, Senior Staff Officer ELLEN K. MANTUS, Senior Staff Officer RUTH E. CROSSGROVE, Managing Editor Vl

TRANSPORTATION RESEARCH BOARD EXECUTIVE COMMITTEE Members GENEVIEVE GIULIANO (Chair), University of Southern California, Los Angeles MICHAEL S. TOWNES ~ Vice Chair), Hampton Roads Transit, Virginia ROBERT E. SKINNER, JR. (Executive Director), National Research Council, Washington, DC MICHAEL W BEHRENS, Texas Department of Transportation, Austin JOSEPH H. BOARDMAN, New York State Department of Transportation, Albany SARAH C. CAMPBELL, TransManagement Inc., Washington DC E. DEAN CARLSON, Independent Consultant, Topeka, KS JOANNE CASEY, Intermodal Association of North America, Greenbelt, MD JAMES C. CODELL III, Kentucky Transportation Cabinet, Frankfort JOHN L. CRAIG, Nebraska Department of Roads, Lincoln BERNARD S. GROSECLOSE JR., South Carolina State Ports Authority, Charleston SUSAN HANSON, Clark University, Worcester, MA LESTER A. HOEL, University of Virginia, Charlottesville HENRY L. HUNGERBEELER, Missouri Department of Transportation, Jefferson City ADIB K. KANAFANI, University of California, Berkeley RONALD F. KIRBY, Metropolitan Washington Council of Governments, Washington DC HERBERT S. LEVINSON, Herbert S. Levinson Transportation Cons., New Haven, CT MICHAEL D. MEYER, Georgia Institute of Technology, Atlanta JEFF P. MORALES, California Nepal lenient of Transportation, Sacramento KAM K. MOVASSAGHI, Louisiana Deltas lenient of Transportation & Development, Baton Rouge CAROL A. MURRAY, New Hampshire Department of Transportation, Concord DAVID Z. PLAVIN, Airports Council International of North America, Washington DC JOHN H. REBENSDORF, Union Pacific Railroad Company, Omaha CATHERINE L. ROSS, Consultant, Atlanta, GA JOHN M. SAMUELS, Norfolk Southern Corporation, Norfolk, VA PAUL P. SKOUTELAS, Port Authority of Allegheny County, Pittsburgh, PA MICHAEL W. WICKHAM, Roadway Express, Inc., Akron, OH . . V11

BOARD ON ATMOSPHERIC SCIENCES AND CLIMATE Members ERIC J. BARRON (Chair), Pennsylvania State University, University Park RAYMOND J. BAN, The Weather Channel, Inc., Atlanta, GA ROBERT C. BEARDSLEY, Woods Hole Oceanographic Institution, Woods Hole, MA ROSINA M. BIERBAUM, The University of Michigan, Ann Arbor HOWARD B. BLUESTEIN, University of Oklahoma, Norman RAFAEL L. BRAS, Massachusetts Institute of Technology, Cambridge STEVEN F. CLIFFORD, University of Colorado, Boulder CASSANDRA G. FESEN, Dan Mouth College, Hanover, NH GEORGE L. FREDERICK, Vaisala Meteorological Systems, Inc., Boulder, CO JUDITH L. LEAN, Naval Research Laboratory, Washington, DC MARGARET A. LEMONE, National Center for Atmospheric Research, Boulder, CO MARIO J. MOLINA, Massachusetts Institute of Technology, Cambridge MICHAEL J. PRATHER, University of California, Irvine WILLIAM J. RANDEL, National Center for Atmospheric Research, Boulder, CO RICHARD D. ROSEN, Atmospheric & Environmental Research, Inc., Lexington, MA THOMAS F. TASCIONE, Sterling Software, Inc., Bellevue, NE JOHN C. WYNGAARD, Pennsylvania State University, University Park . . . vial

OTHER REPORTS OF THE BOARD ON ENVIRONMENTAL STUDIES AND TOXICOLOGY Cumulative Environmental Effects of Alaska North Slope Oil and Gas Development (2003) Estimating the Public Health Benefits of Proposed Air Pollution Regulations (2002) Biosolids Applied to Land: Advancing Standards and Practices (2002) Ecological Dynamics on Yellowstone's Northern Range (2002) The Airliner Cabin Environment and Health of Passengers and Crew (2002) Arsenic in Drinking Water: 2001 Update (2001) Evaluating Vehicle Emissions Inspection and Maintenance Programs (2001) Compensating for Wetland Losses Under the Clean Water Act (2001) A Risk-Management Strategy for PCB-Contaminated Sediments (2001) Acute Exposure Guideline Levels for Selected Airborne Chemicals (3 volumes, 2000-2003) Toxicological Effects of Methylmercury (2000) Strengthening Science at the U.S. Environmental Protection Agency (2000) Scientific Frontiers in Developmental Toxicology and Risk Assessment (2000) Ecological Indicators for the Nation (2000) Modeling Mobile-Source Emissions (2000) Waste Incineration and Public Health (1999) Hormonally Active Agents in the Environment ~ 1999) Research Priorities for Airborne Particulate Matter (4 volumes, 1998-2003) Ozone-Forming Potential of Reformulated Gasoline (1999) Arsenic in Drinking Water (1999) The National Research Council's Committee on Toxicology: The First 50 Years (1997) Carcinogens and Anticarcinogens in the Human Diet (1996) Upstream: Salmon and Society in the Pacific Northwest (1996) Science and the Endangered Species Act (1995) Wetlands: Characteristics and Boundaries (1995) Biologic Markers (5 volumes, 1989-1995) Review of EPA's Environmental Monitoring and Assessment Program (3 volumes, 1994-1995) Science and Judgment in Risk Assessment (1994) Pesticides in the Diets of Infants and Children (1993) Dolphins and the Tuna Industry (1992) Science and the National Parks (1992) Human Exposure Assessment for Airborne Pollutants (1991) Rethinking the Ozone Problem in Urban and Regional Air Pollution (1991) Decline ofthe Sea Turtles (1990) Copies of these reports may be orderedfrom the National Academy Press 6800j 624-6242 or (202) 334-3313 www.nap.edu ix

Acknowledgment of Review Participants This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research CounciT's (NRC's) Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, andresponsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report: Richard Baker, Ford Motor Company Lenora Bohren, Colorado State University Russell Dickerson, University of Maryland Robert Dulia, Sierra Research, Inc. Peter Flachsbart, University of Hawaii at Manoa Bernard D. Goldstein, University of Pittsburgh R. Michael Hardesty, National Oceanic and Atmospheric Administration Roland Hwang, Natural Resources Defense Council lane Milford, University of Colorado at Boulder William Neff, National Oceanic and Atmospheric Administration Robert F. Klausmeier, de la Torre Klausmeier Consulting, Inc. Xl

xii Acknowledgment of Review Participants Andrew Sessler, Lawrence Berkeley National Laboratory Michael Walsh, Consultant Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations, nor did they see the final draft of the report before its release. The review of this report was overseen by William Chameides, Georgia Institute of Technology, and Robert Sawyer, University of Califor- nia, Berkeley. Appointed by the NBC, they were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content ofthisreportrests entirely with the authoring committee and the institution.

Preface Carbon monoxide (CO) is a toxic air pollutant emitted largely from motor vehicles. It is a colorless, odorless, tasteless gas that can produce serious adverse health effects. Breathing CO at high concentrations leads to carboxyhemogIobin poisoning (reduced oxygen transport by hemoglobins, which can lead to impaired reaction timing, headaches, lightheadedness, nausea, coma, and, at high enough concentrations and long enough expo- sure, death. At lower concentrations that can occur in the ambient environ- ment, the effects of CO exposure include increased risk of chest pain and hospitalization for persons with coronary artery disease. Because of the adverse health effects associated with this pollutant, the U.S. Environmen- tal Protection Agency (EPA), as directed by the Clean Air Act, established the health-based National Ambient Air Quality Standards (NAAQS) for CO in 1971. Reducing CO pollution has been one of the greatest success stories in emissions control. Over the past three decades improved motor-vehicle emissions controls have greatly reduced ambient CO concentrations. Most areas that were originally designated as nonattainment areas have come into compliance with the NAAQS for CO. However, certain locations continue to occasionally experience high concentrations of CO. These locations tend to have topographical and meteorological characteristics that exacer- bate pollution. Compliance with the health-based NAAQS for CO has proved difficult under those circumstances. In response to the challenges posed for certain areas by having to come into compliance with the xiii

xiv Preface NAAQS for CO, Congress requested that the National Research Council investigate the characteristics of CO in areas with meteorological and topo- graphical handicaps. In an interim report released in May of 2002, the committee addressed this issue for Fairbanks, Alaska. Many people assisted the committee by providing information related to issues addressed in this report. We gratefully acknowledge Steven Albu, California Air Resources Board; Joseph Cassmassi, South Coast Air Qual- ity Management District; B art Croes, California Air Resources Board; Greg Dana, Alliance of Automobile Manufacturers; Laurence Elmore, EPA; Robert Gibbons, University of Illinois at Chicago; Douglas Lawson, Na- tional Renewable Energy Laboratory; William Neff, National Oceanic and Atmospheric Administration; Dennis Ransel, Clark County, Nevada; Pat- rick Reddy, Colorado Department of Public Health and the Environment; Beate Ritz, University of California, Los Angeles; Shannon Therriault, Missoula City/County Health Department. I am also grateful for the assistance of the National Research Council staff in the preparation of this report. K. John Holmes greatly assisted the committee in his role as project director. The committee also acknowI- edges Raymond A. Wassel, senior program director for environmental sciences and engineering in the Board on Environmental Studies and Toxi- cology (BEST). We thank the other staffmembers who contributed to this report, including Warren Muir, executive director of the Division on Earth and Life Studies; lames J. Reisa, director of BEST; Nancy Humphrey, senior staff officer with the Transportation Research Board; Laurie Geller, senior staff officer with the Board on Atmospheric Sciences and Climate (BASC); Amanda Staudt, staff officer with BASC; Chad Tolman, staff officer with BEST (retired); Kelly Clark, assistant editor with BEST; Mirsada Karalic-Loncarevic, research assistant with BEST; Ramya Chari, research assistant with BEST; and Emily Brady, senior project assistant with BEST. Finally, I would like to thank all the members ofthe committee for their expertise and dedicated effort throughout the study. A~mistead Russell, Ph.D. Chair, Committee on Carbon Monoxide Episodes in Meteorological and Topographical Problem Areas

Contents Summary Ambient Carbon Monoxide Pollution in the United States 16 Introduction, 16 Study Background and Charge, ~ 7 Summary of Interim Report, 21 The Committee's Approach To Its Charge, 22 Report Contents, 23 National Regulatory Setting for Ambient CO, 23 Areas With Recent Exceedances of the CO Standard, 27 Sources of CO Emissions, 31 Health Effects of CO, 39 Relationship of CO to Other Air Pollutants, 51 Equity Considerations in the Spatial Distribution of Ambient CO, 65 Contributions of Topography, Meteorology, and Human Activity to Carbon Monoxide Concentrations 72 Introduction, 72 Meteorology and Topography, 74 Temporal Patterns of CO Concentrations, 82 Vulnerability to Future Exceedances, SS Illustrative Examples, 94 xv

xvi Contents 3 Management of Carbon Monoxide Air Quality. Emissions Control Programs, 100 Monitoring, Models, and Inventories, 129 4 The Future of Carbon Monoxide Air Quality Management Exposures of Concern in the Future, 150 Future CO Management Issues, l S1 Integrating CO Control Into the Overall Air Quality Management System, 156 ..100 .149 References 160 Glossary 1 78 Appendix A. Biographical Information on the Committee on Carbon Monoxide Episodes in Meteorological and Topographical Problem Areas l 89 Appendix B. Abbreviations and Names Used for Classifying Organic Compounds 193 Appendix C. A Simple Box Model with Recirculation 194

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The regulation of carbon monoxide has been one of the great success stories in air pollution control. While more than 90 percent of the locations with carbon monoxide monitors were in violation in 1971, today the number of monitors showing violations has fallen to only a few, on a small number of days and mainly in areas with unique meteorological and topographical conditions.

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