PFAS Multi-site Study (MSS)

About the Study
Multi-Site Study icon

The per- and polyfluoroalkyl substances (PFAS) Multi-site Study (MSS) was authorized by the National Defense Authorization Acts of 2018 and 2019. The study provides information to communities about the health effects of exposure to PFAS. Information learned from the MSS will help all communities in the United States who have been exposed to PFAS through drinking water. Even communities that were not directly involved in this study. More information about the MSS can be found in the Journal of Environmental Health publication: Direct from ATSDR: PFAS MSS

In 2019, CDC and ATSDR announced partnerships with seven study teams to carry out the MSS in communities across the nation.

MSS efforts expand on the work that began with the Pease Study, which was started in 2019 and located in Portsmouth, NH. The Pease Study used data collection and evaluation methods that are now being used at the seven MSS locations. Data collected at each MSS location will be combined with data from the Pease Study. The combined dataset will allow researchers to better explore health outcomes from PFAS exposure.

Graphic: The Multi-site Study Process

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Factsheets about PFAS and Health

To help start a conversation with your doctor about how PFAS can affect your health, please refer to these fact sheets:

Talking to Your Doctor about Exposure to PFAS [English]

Download PDF

Cómo hablar con su médico sobre la exposición a PFAS [Español]

Download PDF

Additional information is available on the ATSDR PFAS Resources page.

Additional ATSDR PFAS Resources

To learn more about PFAS, visit the following web pages.
Coming soon – Materials in Spanish and PDF versions

  1. Understanding PFAS Exposure and Your Body | Per- and Polyfluoroalkyl Substances (PFAS) and Your Health | ATSDR (
  2. Frequently Asked Questions about PFAS Chemicals | ATSDR (

Additional information is available on the ATSDR PFAS Resources page.

MSS Locations

MSS site location map

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For more information on ATSDR regional offices, please refer to the following link:

MSS partners and their study locations:

*For more information on how to participate, please contact your local MSS team or visit their study websites (linked above)

Expected Outcomes of the MSS

The MSS aims to provide a better scientific understanding about the relationships between PFAS exposure via drinking water and certain health outcomes among differing populations. The study also aims to help people understand their risk for health effects. Information gathered from the MSS can be applied to help protect communities across the nation.

MSS teams will collect information about things like immune response, lipid metabolism, kidney function, thyroid disease, liver disease, glycemic parameters, and diabetes. The MSS seeks to enroll at least 2,100 children and 7,000 adults from communities who were exposed to PFAS-contaminated drinking water.

Research involving humans suggests that high levels of certain PFAS may lead to the following:

  • Increased cholesterol levels
  • Changes in liver enzymes
  • Decreased vaccine response in children
  • Increased risk of high blood pressure or pre-eclampsia in pregnant women
  • Small decreases in infant birth weights
  • Increased risk of kidney or testicular cancer

Understanding the relationship between PFAS exposure and health outcomes will allow communities and governmental agencies to make better decisions about how to protect public health.

Child Enrollment in the MSS
A woman hugging a child

Some MSS teams are actively recruiting participants, ages 4-17 years, who meet study criteria. Data collected from child participants will help ATSDR and MSS teams identify any health risks that children may face from exposure to PFAS through their drinking water. If you would like to know if your child is eligible and enroll, please contact your local MSS team.

Community Engagement in the MSS

ATSDR is committed to supporting the MSS teams’ efforts to engage communities in the study. As an agency, ATSDR recognizes that partnering and working with communities is critical to the success of many public health endeavors, including the MSS.

MSS teams will work closely with local and state health agencies, local community organizations, and local media to share information about the study and encourage participation. In addition, study teams may establish a community assistance panel (CAP) to involve the community in decisions related to the study. CAPs may provide input on outreach about the study, participant recruitment strategies, study logistics, and dissemination of study findings within the community. More information on site-specific community engagement activities may be found on study team websites. Team websites are linked in the MSS Locations section.

Technical Workgroups

The MSS teams are

  • using historical reconstruction (HR) methods to research past concentrations of PFAS in the drinking water of study areas and
  • using a type of statistical modeling called pharmacokinetic (PK)/physiologically based pharmacokinetic (PBPK) modeling to research the historical concentrations of PFAS in blood serum levels of affected populations.

ATSDR has established two technical workgroups, the MSS HR Workgroup and the MSS PK Workgroup, to oversee the technical evaluation and the quality assurance of all methods and models used. MSS team representatives serve on these workgroups and facilitate information sharing throughout the study teams.

Information for Healthcare Providers

PFAS resources for clinicians and environmental health professionals, including health assessors, are available at PFAS Information for Clinicians and Environmental Health Professionals.