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

Footnotes

2

Rappaport, S., and M. Smith. 2010. Science 330(6003):460–461. https://doi​.org/10.1126/science.1192603.