Consensus Study Report

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International Standard Book Number-13: 978-0-309-71275-0
International Standard Book Number-10: 0-309-71275-0
Digital Object Identifier: https://doi.org/10.17226/27341

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2024. Health Risks of Indoor Exposure to Fine Particulate Matter and Practical Mitigation Solutions. Washington, DC: The National Academies Press. https://doi.org/10.17226/27341.

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COMMITTEE ON HEALTH RISKS OF INDOOR EXPOSURE TO FINE PARTICULATE MATTER AND PRACTICAL MITIGATION SOLUTIONS

RICHARD L. CORSI (Chair), Dean of Engineering, University of California, Davis

LILIA A. ABRON, President and Chief Executive Officer, PEER Consultants, P.C.

SEEMA BHANGAR, Principal for Healthy Buildings and Communities, U.S. Green Building Council

WANYU (RENGIE) CHAN, Staff Scientist, Lawrence Berkeley National Laboratory

ELIZABETH MATSUI, Professor of Population Health and Pediatrics, Dell Medical School, University of Texas at Austin

LINDA A. MCCAULEY, Professor and Dean, Nell Hodgson Woodruff School of Nursing, Emory University

MEREDITH C. MCCORMACK, Associate Professor of Medicine, Johns Hopkins University School of Medicine

KIMBERLY A. PRATHER, Atmospheric Chemist, Distinguished Chair in Atmospheric Chemistry, and Distinguished Professor, Scripps Institution of Oceanography and the Department of Chemistry and Biochemistry, University of California San Diego

JEFFREY SIEGEL, Professor of Civil Engineering, University of Toronto

BRENT STEPHENS, Professor of Architectural Engineering and Department Chair, Illinois Institute of Technology

MARINA E. VANCE, Associate Professor and McLagan Family Faculty Fellow, University of Colorado Boulder

National Academy of Engineering staff

DAVID A. BUTLER, J. Herbert Hollomon Scholar, Study Director

COURTNEY HILL, Program Officer (until January 2023)

CASEY GIBSON, Associate Program Officer (from January 2023)

MAIYA SPELL, Senior Program Assistant (until January 2023)

CHESSIE BRIGGS, Senior Program Assistant (from March 2023)

GURU MADHAVAN, Norman R. Augustine Senior Scholar, Senior Director of Programs

Reviewers

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 CHARLES HAAS (NAE), Drexel University, and GLEN DAIGGER (NAE), University of Michigan. They 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.

Contents

SUMMARY

1 INTRODUCTION

What Is Fine Particulate Matter?

Why Is It Important to Study Indoor Exposure to Fine Particulate Matter?

The Study’s Statement of Task

The Committee’s Approach to Its Task

Methodologic Considerations

Report Organization and Framework

References

2 BACKGROUND

The U.S. EPA’s Role in Indoor Environmental Quality

National Academies Reports Addressing Related Topics

References

3 SOURCES AND COMPOSITION OF INDOOR PARTICULATE MATTER

Introduction and Background

Indoor PM_2.5 Concentrations and Composition

Regional, Area, and Local Differences and Cultural/Socioeconomic Disparities in the Sources and Composition of Indoor PM

Findings and Conclusions

Recommendations

References

4 PARTICLE DYNAMICS AND BUILDING CHARACTERISTICS THAT INFLUENCE INDOOR PM

Particles in Indoor Environments

Indoor Particle Dynamics: Defining Mechanisms

Measuring Indoor Particle Dynamics

Socioeconomic Disparities in Indoor Particle Dynamics

Observations and Recommendations

References

5 EXPOSURE TO INDOOR PM

Scope and Introduction

Exposure Assessment Methods

Exposure Trends and Disparities

Indoor Exposure Assessment to Inform Health and Mitigation

Findings and Conclusions

References

6 HEALTH EFFECTS FROM EXPOSURE TO INDOOR PM

Introduction

Respiratory Health Effects

Cardiovascular Health Outcomes

Cancer Outcomes

Neurological Outcomes

Reproductive Outcomes

Diabetes and Metabolic Syndrome

Conclusions and Recommendations

References

7 PRACTICAL MITIGATION SOLUTIONS FOR INDOOR PM

Introduction

Framework

Literature Review Methodology

Literature Review Results

Considerations Across All Mitigation Measures

Conclusions and Recommendations

References

8 KEY FINDINGS, CONCLUSIONS, AND RECOMMENDATIONS

Overview of the Committee’s Work

Key Conclusions

Overarching Recommendations

APPENDIXES

A AGENDAS – 2021 WORKSHOP SERIES ON INDOOR EXPOSURE TO FINE PARTICULATE MATTER AND PRACTICAL MITIGATION APPROACHES

B BIOGRAPHIC SKETCHES OF COMMITTEE MEMBERS AND PROJECT STAFF

Box, Figures, and Tables

BOX

8-1 Synopsis – What Is and Isn’t Known about the Health Risks of Indoor Exposure to Fine Particulate Matter and Practical Mitigation Solutions

FIGURES

4-1 Sources, Sinks, and Transformations of Indoor PM

5-1 The Connections Among Sources, Transformations, and Mitigation, and Their Influence on Indoor Exposure to Fine PM

6-1 Overview of Diseases, Conditions, and Biomarkers Affected by Outdoor Air Pollution

TABLES

3-1 Examples of Indoor Sources of PM_2.5 That Are Relevant in Many U.S. Homes and Schools, With Some of Their Characteristics

4-1 Sources, Sinks, and Transformations of Indoor PM and Key Affecting Parameters

7-1 Mitigation Measures and the Contextual Factors That Influence Their Impact

7-2 Search Terms Used in the Review of Practical Mitigation Measures

7-3 Summary of Selected Studies Addressing Mitigation of Indoor PM Exposure, Grouped by Health Outcomes

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