Consensus Study Report

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This activity was supported by contracts between the National Academy of Sciences and Centers for Disease Control and Prevention, the National Institute of Standards and Technology, and the National Institutes of Health, Department of Health and Human Services, under Contract No. HHSN263201800029I. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

International Standard Book Number-13: 978-0-309-27705-1
International Standard Book Number-10: 0-309-27705-1
Digital Object Identifier: https://doi.org/10.17226/26460
Library of Congress Control Number: 2022949390

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2022. The Chemistry of Fires at the Wildland-Urban Interface. Washington, DC: The National Academies Press. https://doi.org/10.17226/26460.

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COMMITTEE ON THE CHEMISTRY OF URBAN WILDFIRES

Members

DAVID T. ALLEN (NAE), Chair, The University of Texas at Austin

OLORUNFEMI ADETONA, The Ohio State University

MICHELLE BELL (NAM), Yale University

MARILYN BLACK, Underwriters Laboratories Inc.

JEFFEREY L. BURGESS, University of Arizona

FREDERICK L. DRYER (NAE), University of South Carolina

AMARA HOLDER, US Environmental Protection Agency

ANA MASCAREÑAS, Independent Consultant

FERNANDO L. ROSARIO-ORTIZ, University of Colorado Boulder

ANNA A. STEC, University of Central Lancashire

BARBARA J. TURPIN, University of North Carolina at Chapel Hill

JUDITH T. ZELIKOFF, New York University

Staff

MEGAN E. HARRIES, Study Director (until August 2022)

LIANA VACCARI, Study Director

BRENNA ALBIN, Program Assistant

EMILY J. BUEHLER, Consultant

KESIAH CLEMENT, Research Associate (until July 2021)

CHARLES FERGUSON, Senior Board Director

MEGHAN HARRISON, Senior Program Officer (until July 2021)

ELLEN K. MANTUS, Scholar (until April 2021)

JEREMY T. MATHIS, Board Director (until March 2021)

MARILEE SHELTON-DAVENPORT, Senior Program Officer (until January 2021)

ABIGAIL ULMAN, Research Assistant (until May 2022)

BENJAMIN ULRICH, Senior Program Assistant (until March 2022)

Sponsors

CENTERS FOR DISEASE CONTROL AND PREVENTION

NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES

NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY

BOARD ON CHEMICAL SCIENCES AND TECHNOLOGY

Members

SCOTT COLLICK, Co-chair, DuPont

JENNIFER SINCLAIR CURTIS, Co-chair, University of California, Davis

GERARD BAILLELY, Procter and Gamble

RUBEN G. CARBONELL (NAE), North Carolina State University

JOHN FORTNER, Yale School of Engineering and Applied Science

KAREN I. GOLDBERG (NAS), University of Pennsylvania

JENNIFER M. HEEMSTRA, Emory University

JODIE L. LUTKENHAUS, Texas A&M University

SHELLEY D. MINTEER, University of Utah

AMY PRIETO, Colorado State University

MEGAN L. ROBERTSON, University of Houston

SALY ROMERO-TORRES, Thermo Fisher Scientific

REBECCA T. RUCK, Merck Process Research & Development

ANUP K. SINGH, Lawrence Livermore National Laboratory

VIJAY SWARUP, ExxonMobil

Staff

CHARLES FERGUSON, Senior Board Director

MEGAN E. HARRIES, Program Officer (until August 2022)

LIANA VACCARI, Program Officer

LINDA NHON, Associate Program Officer

THANH NGUYEN, Finance Business Partner

JESSICA WOLFMAN, Research Associate

BRENNA ALBIN, Program Assistant

AYANNA LYNCH, Program Assistant

Acknowledgments

This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.

We thank the following individuals for their review of this report:

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report, nor did they see the final draft before its release. The review of this report was overseen by Susan Brantley, The Pennsylvania State University, and Martin-Jose J. Sepulveda, Florida International University. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.

This study would not have been successful without the assistance of many. The committee is grateful to the people who helped provide research support to the report, including Colette Schissel, The University of Texas at Austin; Yosuke Kimura, The University of Texas at Austin; and the staff of the National Academies Research Center. We are especially grateful to the numerous expert individuals who spoke to the committee during an open information-gathering session or otherwise provided input (see Appendix D).

Acronyms and Abbreviations

CHEMICAL FORMULAS

Contents

SUMMARY

1 INTRODUCTION

Wildfires at the WUI

The Committee and Its Task

The Committee’s Approach to Its Task

The Committee’s Approach to Equity

Prior Related Work by the National Academies

Organization of This Report

References

2 DEFINING AND CONTEXTUALIZING WUI FIRES

Defining the WUI

Defining Spatial and Temporal Scales

Factors Contributing to Increasing WUI Fires

The Impacts of WUI Fires

Using Examples to Contextualize WUI Fires

Findings from Recent Examples of WUI Fires

References

3 MATERIALS, COMBUSTION, AND EMISSIONS IN WUI FIRES

Materials

Combustion

Emissions

References

4 ATMOSPHERIC TRANSPORT AND CHEMICAL TRANSFORMATIONS

Primary Species with Toxic Potential Downwind of WUI Fires

Atmospheric Transformations

Current Practice in Modeling Far Plumes

References

5 WATER AND SOIL CONTAMINATION

Impacts to Water Quality Related to Community Water Systems

Impacts to Groundwater and Soil Contamination

Impacts of Atmospheric Wet and Dry Deposition

References

6 HUMAN EXPOSURES, HEALTH IMPACTS, AND MITIGATION

Chemicals of Concern for Human Exposure

Vulnerable Populations, Health Equity, and Environmental Justice

Routes of Exposure

Health Impacts

Reducing Exposure Risks and Health Effects

Conclusion

References

7 MEASUREMENT OF WUI FIRES: EMISSIONS AND EXPOSURES

An Overview of Data and Measurement Systems for WUI Fires

Detecting and Determining the Areal Extent of WUI Fires

Measuring Fuels and Estimating Emissions

Measuring Emissions in the Field

Monitoring Emissions Using Continuous/Ambient Networks

Assessing Exposure

Sampling and Analytical Methods

Coordinating Measurements of WUI Fires

References

8 THE FUTURE OF WUI FIRE RESEARCH

Research Agenda

Cross-Disciplinary Coordination

Information Dissemination

APPENDIXES

A GLOSSARY

B COMMITTEE BIOGRAPHICAL SKETCHES

C AVAILABLE DATA FOR EXAMPLE FIRES

D PUBLIC WORKSHOP AGENDA

E ENGINEERING CALCULATIONS FOR TABLE 3-2