Consensus Study Report
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This study was sponsored by the Alfred P. Sloan Foundation, the Centers for Disease Control and Prevention, the Environmental Protection Agency, and the National Institute of Environmental Health Sciences. This activity was supported by contracts between the National Academies of Sciences, Engineering, and Medicine and in whole or in part with Federal funds from the National Institutes of Health, Department of Health and Human Services, under Contract No. HHSN263201800029I Task Order No. 75N98020F00009. 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: 978-0-309-08399-7
International Standard Book Number-10: 0-309-08399-0
Digital Object Identifier: https://doi.org/10.17226/26228
Library of Congress Control Number: 2022946407
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2022. Why Indoor Chemistry Matters. Washington, DC: The National Academies Press. https://doi.org/10.17226/26228.
The National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, nongovernmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research. Dr. Marcia McNutt is president.
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Consensus Study Reports published by the National Academies of Sciences, Engineering, and Medicine document the evidence-based consensus on the study’s statement of task by an authoring committee of experts. Reports typically include findings, conclusions, and recommendations based on information gathered by the committee and the committee’s deliberations. Each report has been subjected to a rigorous and independent peer-review process and it represents the position of the National Academies on the statement of task.
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COMMITTEE ON EMERGING SCIENCE ON INDOOR CHEMISTRY
Members
DAVID C. DORMAN (Chair), North Carolina State University
JONATHAN ABBATT, University of Toronto
WILLIAM P. BAHNFLETH, Pennsylvania State University
ELLISON CARTER, Colorado State University
DELPHINE FARMER, Colorado State University
GILLIAN GAWNE-MITTELSTAEDT, Partnership for Air Matters/Tribal Healthy Homes Network
ALLEN H. GOLDSTEIN, University of California, Berkeley
VICKI H. GRASSIAN, University of California, San Diego
RIMA HABRE, University of Southern California
GLENN MORRISON, University of North Carolina, Chapel Hill
JORDAN PECCIA, Yale University
DUSTIN POPPENDIECK, National Institute of Standards and Technology
KIMBERLY A. PRATHER (NAS/NAE), University of California, San Diego
MANABU SHIRAIWA, University of California, Irvine
HEATHER M. STAPLETON, Duke University (since February 2021)
MEREDITH WILLIAMS, California Department of Toxic Substances Control
Staff
MEGAN E. HARRIES, Study Director
MICHELLE BAILEY, Program Assistant (until July 2021)
KESIAH CLEMENT, Research Associate (until July 2021)
MEGHAN HARRISON, Senior Program Officer (until July 2021)
ELLEN K. MANTUS, Scholar (until April 2021)
EMMA SCHULMAN, Program Assistant (until March 2022)
MARILEE SHELTON-DAVENPORT, Senior Program Officer (until January 2021)
ABIGAIL ULMAN, Research Assistant (until November 2021)
BENJAMIN ULRICH, Senior Program Assistant (until August 2021)
BOARD ON CHEMICAL SCIENCES AND TECHNOLOGY
Members
SCOTT COLLICK (Co-Chair), DuPont
JENNIFER SINCLAIR CURTIS (Co-Chair), University of California, Davis
GERARD BAILLELY, The Procter & Gamble Co.
RUBEN G. CARBONELL (NAE), North Carolina State University
JOHN FORTNER, Yale University
JEN HEEMSTRA, Emory University
JODIE L. LUTKENHAUS, Texas A&M University
SHELLEY MINTEER, University of Utah
AMY PRIETO, Colorado State University
MEGAN ROBERTSON, University of Houston
SALY ROMERO-TORRES, Thermo Fisher Scientific
REBECCA T. RUCK, Merck Research Laboratories
ANUP KUMAR SINGH, Lawrence Livermore National Laboratory
VIJAY SWARUP, ExxonMobil Research and Engineering Corporation
Staff
CHARLES FERGUSON, Senior Board Director
BRENNA ALBIN, Program Assistant
MEGAN E. HARRIES, Program Officer
AYANNA LYNCH, Program Assistant
LINDA NHON, Associate Program Officer
EMMA SCHULMAN, Program Assistant
ABIGAIL ULMAN, Research Assistant
LIANA VACCARI, Program Officer
JESSICA WOLFMAN, Research Associate
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 Cynthia Beall (NAS), Case Western Reserve University, and Teresa Fryberger, Consultant, Chemical Sciences and Policy. 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.
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Acronyms
| AMS | aerosol mass spectrometers |
| ANSI | American National Standards Institute |
| CADR | clean air delivery rate |
| CARB | California Air Resources Board |
| CFD | computational fluid dynamics |
| CIMS | chemical ionization mass spectrometry |
| EC | elemental carbon |
| EDC | endocrine-disrupting chemical |
| EJ | environmental justice |
| EPA | U.S. Environmental Protection Agency |
| ESP | electrostatic precipitator |
| HEPA | high-efficiency particulate air |
| HOM | highly oxygenated organic molecule |
| HOMEChem | House Observations of Microbial and Environmental Chemistry |
| HVAC | heating, ventilation, and air conditioning |
| IOM | Institute of Medicine |
| MERV | Minimum Efficiency Reporting Value |
| mVOC | microbial volatile organic compound |
| NHANES | National Health and Nutrition Examination Survey |
| NHAPS | National Human Activity Patterns Survey |
| NRC | National Research Council |
| OA | organic aerosol |
| PAH | polycyclic aromatic hydrocarbon |
| PBDE | polybrominated diphenyl ether |
| PCB | polychlorinated biphenyl |
| PCO | photocatalytic oxidation |
| PFAS | per- and polyfluoroalkyl substances |
| PM | particulate matter |
| PM2.5 | fine particulate matter |
| PMF | positive matrix factorization |
| PPE | personal protective equipment |
| PTR-MS | proton-transfer-reaction mass spectrometer |
| RIOPA | Relationship of Indoor, Outdoor, and Personal Air study |
| ROS | reactive oxygen species |
| SDO | standards developing organization |
| SDS | Safety Data Sheet |
| SOA | secondary organic aerosol |
| SVOC | semivolatile organic compound |
| SV-TAG | semivolatile thermal desorption aerosol gas chromatography |
| TAG | thermal desorption aerosol gas chromatography |
| TCE | trichloroethylene |
| TEG | triethylene glycol |
| TSCA | Toxic Substances Control Act |
| UFP | ultrafine particle |
| UHI | urban heat islands |
| UV | ultraviolet |
| UVGI | ultraviolet germicidal irradiation |
| VCP | volatile chemical product |
| VOC | volatile organic compound |
CHEMICAL FORMULAS
| Cl2 | chlorine |
| ClNO2 | nitryl chloride |
| CO | carbon monoxide |
| CO2 | carbon dioxide |
| HO2 | hydroperoxy |
| H2O2 | hydrogen peroxide |
| HOCl | hypochlorous acid |
| HONO | nitrous acid |
| H2SO3 | sulfurous acid |
| NH3 | ammonia |
| NO | nitric oxide |
| NO2 | nitrogen dioxide |
| NOx | nitrogen oxides |
| O3 | ozone |
| OH | hydroxyl |
| SiO2 | silica or silicon dioxide |
| TiO2 | titanium dioxide |
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Contents
Prior Efforts on Which This Report Builds
Organization of This Consensus Report
2 PRIMARY SOURCES AND RESERVOIRS OF CHEMICALS INDOORS
Major Primary Sources, Reservoirs, and Factors That Influence Emission Rates
Classes of Compounds in Indoor Environments
Analytical Methods and Challenges
3 PARTITIONING OF CHEMICALS IN INDOOR ENVIRONMENTS
Indoor Environmental Reservoirs and Surfaces
Partitioning among Reservoirs and Phases Found in Indoor Environments
Size and Capacity of Different Indoor Reservoirs
Partitioning Thermodynamics: Effects of Temperature and Relative Humidity
Partitioning Dynamics, Timescales, and Limitations on the Equilibrium Concept
Current Science on Partitioning of Chemicals in Indoor Environments
5 MANAGEMENT OF CHEMICALS IN INDOOR ENVIRONMENTS
Management through Capture and Removal
Management through Chemical Transformations
Other Considerations for Management of Chemicals
6 INDOOR CHEMISTRY AND EXPOSURE
Exposure Definitions, Settings, and Timing
Environmental Health Disparities and Exposure Variables
The Intersection of Indoor Chemistry and Exposure Modeling
Measurement Science for Exposure
7 A PATH FORWARD FOR INDOOR CHEMISTRY
Chemical Complexity in the Indoor Environment
Indoor Chemistry in a Changing World
Future Investments in Research
Communicating Science and Risks: Indoor Chemistry and Environmental Quality
