Consensus Study Report
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This project was funded with federal funds from the Centers for Disease Control and Prevention under contract number 200-2011-38807, task order number 75D30121F00099; National Institutes of Environmental Health Sciences, National Institutes of Health, and U.S. Department of Health and Human Services, under Contract No. HHSN2632018000291, task order number 75N98020F00012. 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: 978-0-309-48244-8
International Standard Book Number-10: 0-309-48244-5
Digital Object Identifier: https://doi.org/10.17226/26156
Library of Congress Control Number: 2022943858
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2022. Guidance on PFAS Exposure, Testing, and Clinical Follow-Up. Washington, DC: The National Academies Press. https://doi.org/10.17226/26156.
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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 THE GUIDANCE ON PFAS TESTING AND HEALTH OUTCOMES
BRUCE N. CALONGE (Chair), University of Colorado School of Medicine and School of Public Health
LAURA ANDERKO, Mid-Atlantic Center for Children’s Health and the Environment, M. Fitzpatrick College of Nursing, Villanova University
DANA BOYD BARR, Emory University Rollins School of Public Health
ERIN BELL, School of Public Health, University at Albany
KEVIN ELLIOTT, Michigan State University
MELISSA GONZALES, Tulane University School of Public Health and Tropical Medicine
ERIN HAYNES, University of Kentucky College of Public Health
JANE HOPPIN, North Carolina State University
TAMARRA JAMES-TODD, Harvard T.H. Chan School of Public Health
ALEX KEMPER, The Ohio State University College of Medicine; Nationwide Children’s Hospital
BRIAN LINDE, Yale School of Medicine
MARC-ANDRÉ VERNER, Université de Montréal
VERONICA VIEIRA, University of California, Irvine
XIAOBIN WANG, Johns Hopkins Bloomberg School of Public Health and School of Medicine
CHRIS WIANT, Caring for Colorado Foundation
Health and Medicine Division Staff
ELIZABETH BARKSDALE BOYLE, Study Director
ALEXIS WOJTOWICZ, Associate Program Officer
ALEXANDRA MCKAY, Senior Program Assistant
ROSE MARIE MARTINEZ, Senior Board Director, Board on Population Health and Public Health Practice
Division on Earth and Life Studies Staff
MARILEE SHELTON-DAVENPORT, Senior Program Officer (until March 2022)
KATE GUYTON, Senior Program Officer
KALEY BEINS, Program Officer
CLIFFORD DUKE, Board Director, Board on Environmental Studies and Toxicology
ALLIE BOMAN, Briere Associates, Inc.
RONA BRIERE, Briere Associates, Inc.
CARY HAVER, ICF Resources, LLC
JORDAN KUIPER, Johns Hopkins University
JUDY LAKIND, LaKind Associates
KATE MARQUESS, Johns Hopkins University
MELISSA MILLER, ICF Resources, LLC
JOSH NAIMAN, LaKind Associates
ANNA RUTH ROBUCK, Icahn School of Medicine at Mount Sinai
MARGARET SHANDLING, Briere Associates, Inc.
LAUREN TOBIAS, Maven Messaging
LAURENE ALLEN, Merrimack Citizens for Clean Water
ANDREA AMICO, Testing for Pease
STEL BAILEY, Fight for Zero
KYLA BENNETT, Public Employees for Environmental Responsibility
KAREN BLONDEL, Public Housing Civic Association, Inc.
PHIL BROWN, Northeastern University
ALBERTO J. CABAN-MARTINEZ, University of Miami
CHERYL CAIL, South Carolina Indian Affairs Commission/SC Idle No More
COURTNEY CARIGNAN, Michigan State University
TRACY CARLUCCIO, Delaware Riverkeeper Network
JAMIE DEWITT, East Carolina University
EMILY DONOVAN, Clean Cape Fear
ALAN DUCATMAN, West Virginia University
PATRICK ELDER, Military Poisons
TERESA GERADE, Don’t Undermine Memphremagog’s Purity
HOPE GROSSE, Buxmont Coalition for Safe Water
LOREEN HACKETT, PFOA Project New York
AYESHA KHAN, Nantucket PFAS Action Group
RAINER LOHMANN, University of Rhode Island Superfund Research Center
SAMRAA LUQMAN, Concerned Residents for South Dearborn
BETH MARKESINO, North Carolina Stop Gen-X In Our Water
AARON MARUZZO, University of California, Berkeley
TOBYN MCNAUGHTON, Resident of Belmont, Michigan
KRISTEN MELLO, Westfield Residents Advocating for Themselves
PAMELA K. MILLER, Alaska Community Action on Toxics
ELIZABETH NEARY, Wisconsin Environmental Health Network
LAURA OLAH, Citizens for Safe Water Around Badger
JACOB PARK, University of Johannesburg, Castleton University
SUE PHELAN,1 GreenCAPE
ANDREA RICH, Save Our Water
DANA SARGENT, Cape Fear River Watch
LAUREL SCHAIDER, Silent Spring Institute
LINDA SHOSIE, Mothers for Safe Air & Safe Water
LENNY SIEGEL, Center for Public Environmental Oversight
MIKE WATTERS, Gray’s Creek Residents United Against PFAS in our Wells and Rivers
LA’MESHIA WHITTINGTON, Meredith College/North Carolina Black Alliance
ALAN WOOLF, Harvard Medical School
CATHY WUSTERBARTH, Need Our Water
SANDY WYNN-STELT, Great Lakes PFAS Action Network
1 Deceased January 2022.
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 Joshua Sharfstein, Johns Hopkins Bloomberg School of Public Health, and Susan Brantley, The Pennsylvania State 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.
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Many people were critical in helping the committee accomplish its charge. The committee gratefully acknowledges the work of the community liaisons who provided insight and viewpoints pertinent to planning for our public meetings. In particular, we thank Andrea Amico, Emily Donovan, Patrick Elder, Ayesha Khan, Kristen Mello, and Laura Olah, who provided helpful insights on the perspectives and experiences of their communities that informed our community engagement methods. This engagement ensured that our public meetings would include the relevant perspectives, which allowed us to learn about the social, environmental, public health, and medical challenges central to our charge. In addition, we found the information and perspectives provided by the presentations and discussions at our public meetings immensely helpful in informing our deliberations (see Appendix C).
The committee’s work was enhanced by the technical expertise; writing contributions; data evaluation, visualization, and extraction; and other support provided by Cary Haver, Jordan Kuiper, Judy Lakind, Kate Marquess, Melissa Miller, Josh Naiman, Anna Ruth Robuck, and Lauren Tobias, who served as consultants. We would also like to acknowledge the U.S. Environmental Protection Agency’s Office of Water and Office of Research and Development for sharing publicly available abstracted data from some of the epidemiologic studies included in our literature review, as well as Scott M. Bartell and Nicholas Cuvelier from the University of California, Irvine, for calculating percentiles of per- and polyfluoroalkyl (PFAS) exposure.
Importantly, the committee heard from a number of individuals who shared their personal stories about and experiences with PFAS exposure, testing, and clinical follow-up. These discussions helped ground our work in the lived experiences of the complex issues that had to be tackled in this report, and we are extremely grateful for their courage in sharing those experiences in a public forum.
The committee thanks the staff of the National Academies of Sciences, Engineering, and Medicine who contributed to producing this report, especially the extraordinary, creative, and tireless study staff: Kaley Beins, Elizabeth Boyle, Clifford Duke, Kathryn Guyton, Rose Marie Martinez, Alexandra McKay, Marilee Shelton-Davenport, and Alexis Wojtowicz. Thanks as well go to other staff in the Division on Earth and Life Studies who provided additional support, including Tamara Dawson, Eric Edkin, Elizabeth Eide, Lauren Everett, Nancy Huddleston, Radiah Rose, and Maggie Walser. This project also received important assistance from Megan Lowry (Office of News and Public Information) and Matthew Anderson (Office of Financial Administration). Valuable research assistance was provided by Christopher Lao-Scott, senior research librarian in the National Academies Research Center. Finally, a thank you is extended to Rona Briere and Allison Boman, who assisted the committee with editing the report.
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The creation of the U.S. Environmental Protection Agency (EPA) in 1970 signaled public recognition of industrial impacts on the environment. The government subsequently acknowledged that three elements essential for life—air, water, and food—could be contaminated by industrial activity and threaten human health. In 1980, two steps were taken in response to the government’s concern: passage of the Comprehensive Environmental Response, Compensation, and Liability Act and creation of the Agency for Toxic Substances and Disease Registry (ATSDR).
The mission of ATSDR is to prevent or mitigate the adverse impacts on human health and diminished quality of life resulting from exposure to hazardous substances in the environment. The earliest contaminants of concern included pesticides; heavy metals from mining; asbestos; munitions and their manufacturing by-products (including radioactive substances); petrochemicals, including solvents; and products and by-products associated with oil and gas extraction, refinement, and use. Over time, additional industrial products with significant potential to affect the population’s health have been identified, including the class of chemicals known as per- and polyfluoroalkyl substances, or PFAS. PFAS have useful properties, such as oil and water repellency, temperature resistance, and friction reduction. For decades, they have been used in numerous applications and products, such as firefighting; chrome-plating; lubricants; insecticides; and coatings and treatments for such surfaces as carpeting, packaging, and cookware. As a result of the production and use of PFAS, many sites across the country are contaminated with PFAS, which in turn can result in contamination of soils and drinking water.
ATSDR faces a critical challenge in protecting people from the potential health impacts of PFAS exposures. Data from the National Health and Nutrition Examination Survey show that nearly 100 percent of people in the United States are exposed to at least one PFAS, but at what level of exposure do harms to human health occur? What PFAS-associated health outcomes might benefit from clinical follow-up or care? Would there be any benefit in testing people to know their PFAS exposure level? What clinical follow-up can help protect people from PFAS-associated harms?
Answering these questions requires bridging approaches used for chemical hazard assessments, such as those carried out by the EPA; public and community health benefits, such as those laid out in the Community Guide to Preventive Services; and medical care health benefit assessments, such as those of the U.S. Preventive Services Task Force. Chemical hazard assessments are conducted to determine whether a chemical exposure causes harm; public health assessments address the impact on and interventions to mitigate threats to the health of a population or community; and medical care health benefit assessments evaluate the effects of medical interventions, including their beneficial effects and potential adverse outcomes. One challenge with blending these different approaches is that in medical care health benefit assessments, the “gold standard” for informing clinical risk/benefit decisions for medical interventions is the randomized controlled trial (RCT). However, RCTs are typically impossible for chemical hazard assessments, for both ethical and practical reasons. For example, most environmental chemicals are not developed to improve human health, making intentional exposures in an RCT unethical. Chemical exposures also vary and may or may not be significant depending on the agent’s toxicity, which sometimes makes controlled trials infeasible. And public health assessments, in which comparative studies are still required to support evidence-based recommendations, usually require many years of data and are challenged by the long-standing and often-lamented separation of health care and public health.
In 2010, researchers Stephen Rappaport and Martyn Smith reported that “70 to 90% of disease risks are probably due to differences in environments” and made the case for a more comprehensive approach to evaluating environmental exposures in order to understand the causes of and contributors to
chronic disease.2 Such an approach has, as in the case of lead, and will, for chemicals such as PFAS, ultimately depend on breaking down the barriers between environmental public health and the clinical care setting. These two health sectors have had some limited success in bridging the gap for infectious disease outbreaks and epidemics. Identifying environmental exposures, measuring exposure levels in patients, and providing indicated medical follow-up are elements of a critical frontier that could and should bring the two disciplines closer together to improve the health of those in the nation’s communities.
Another challenge for the study committee was the critical need to include community voices in the study process as an important and credible source of evidence to inform guidance recommendations. To meet that challenge, this study included the testimony of more than 30 people who live in or work with a community impacted by PFAS contamination. Community members provided the committee with much needed data based on their lived experiences with PFAS contamination, and moved the committee’s work from an academic exercise to a personal reality. The committee used the presentations of community members to inform frameworks within the report and to gain an understanding of the social context that the committee’s recommendations will inform.
Atmospheric chemist Susan Solomon has suggested that successfully addressing environmental challenges requires making the problem personal, perceptible, and practical. The voices of affected individuals in contaminated communities make the PFAS issue personal, while the scientists researching the associations with human health make the impacts of PFAS exposure perceptible. In this report, the committee has endeavored to provide practical recommendations that can aid policy makers, state and federal environmental and public health agencies, clinicians, and concerned individuals in addressing this important health problem.
Bruce N. Calonge, Chair
Committee on the Guidance on PFAS Testing and Health Outcomes
BOXES, FIGURES, AND TABLES
3-11 Adjusted risk estimates for preeclampsia, gestational hypertension (hypertension without preeclampsia), and hypertensive disorders of pregnancy and 95% confidence intervals by study and PFAS PFOS exposure category
3-12 Adjusted risk estimates for preeclampsia, gestational hypertension (hypertension without preeclampsia), and hypertensive disorders of pregnancy and 95% confidence intervals by study and PFOA exposure category
3-13 Adjusted risk estimates for preeclampsia, gestational hypertension (hypertension without preeclampsia), and hypertensive disorders of pregnancy and 95% confidence intervals by study and PFuDA and PFDA exposure category
3-14 Adjusted risk estimates for preeclampsia, gestational hypertension (hypertension without preeclampsia), and hypertensive disorders of pregnancy and 95% confidence intervals by study and PFHxS exposure category
3-15 Adjusted risk estimates for preeclampsia, gestational hypertension (hypertension without preeclampsia), and hypertensive disorders of pregnancy and 95% confidence intervals by study and PFNA exposure category
5-5 Graphical display of the levels of PFAS to inform clinical care for the sum of MeFOSAA, PFHxS, PFOA (linear and branched isomers), PFDA, PFUnDA, PFOS (linear and branched isomers), and PFN in serum or plasma
E-2 Examples of PFAS content (micrograms per kilogram [μg/kg] wet weight [ww]) in raw and steamed seafood samples and percentages of PFAS content increase (+) and decrease (−) after steaming (mean ± standard deviation [SD])
E-6 Limited data on PFAS levels in breast milk and infant formula in the United States show general overlapping concentrations, which also overlap with PFAS concentrations in drinking water that could be used to reconstitute formula
|AAFP||American Academy of Family Physicians|
|AAP||American Academy of Pediatrics|
|ACOG||American College of Obstetricians and Gynecologists|
|AHRQ||Agency for Healthcare Research and Quality|
|ANHE||Alliance of Nurses for Health Environments|
|ASTHO||Association of State and Territorial Health Officials|
|ATSDR||Agency for Toxic Substances and Disease Registry|
|BLL||blood lead level|
|BMI||body mass index|
|CAS||Chemical Abstract Services|
|CDC||Centers for Disease Control and Prevention|
|CERCLA||Comprehensive Environmental Response, Compensation, and Liability Act|
|CMS||Centers for Medicare & Medicaid Services|
|CPG||clinical practice guideline|
|CPT||Current Procedural Terminology|
|DOD||U.S. Department of Defense|
|EFSA||European Food Safety Authority|
|EPA||U.S. Environmental Protection Agency|
|EVIDEM||Evidence and Value in Decision Making|
|EWG||Environmental Working Group|
|FDA||U.S. Food and Drug Administration|
|GRADE||Grading of Recommendations, Assessment, Development and Evaluations|
|HHS||U.S. Department of Health and Human Services|
|HMB||German Human Biomonitoring Commission|
|IARC||International Agency for Research on Cancer|
|IOM||Institute of Medicine|
|LOD||limit of detection|
|MCL||maximum contaminant level|
|MeFOSAA||methylperfluorooctane sulfonamidoacetic acid|
|NAS||National Academy of Sciences|
|NHANES||National Health and Nutrition Examination Survey|
|NIEHS||National Institute of Environmental Health Sciences|
|NIOSH||National Institute for Occupational Safety and Health|
|NIST-SRM||National Institute of Standards and Technology Standard Reference Material|
|NRC||National Research Council|
|NTP||National Toxicology Program|
|OECD||Organisation for Economic Co-operation and Development|
|OSHA||Occupational Safety and Health Administration|
|PBPK||physiologically based pharmacokinetic|
|PEHSU||Pediatric Environmental Health Specialty Unit|
|PFAS-REACH||PFAS Research, Education, and Action for Community Health|
|PFBS||perfluorobutane sulfonic acid|
|PFCA||perfluorinated aliphatic carboxylic acid|
|PFHxS||perfluorohexane sulfonic acid|
|PFOS||perfluorooctane sulfonic acid|
|SSEHRI||Social Science Environmental Health Research Institute|
|TSCA||Toxic Substances Control Act|
|USDA||U.S. Department of Agriculture|
|USPSTF||U.S. Preventive Services Task Force|
|VHA||Veterans Health Administration|
|WHO||World Health Organization|