PFAS: “Forever Chemicals” and the Anacostia Watershed

There is increasing chatter in the news regarding the growing concerns about “forever chemicals” found in our air, water, and even our food. These forever chemicals are referred to by many different acronyms with some of the most common including PFOA, PFOS, and PFAS. But, what are they?

What are PFAS?

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are two of the most widely found members of a chemical group called per- and polyfluoroalkyl substances (PFAS) which includes thousands of different chemicals (more than 9,000 to date). Chemicals in the PFAS chemical group break down very slowly and can be very long lasting. They’ve been widely used since the 1940s for household goods ranging from food packaging to cosmetics as well as industrial production in the automotive, construction, electronic, and aerospace industries. They can help make products resistant to heat, stains, grease, and oil. Many non-stick surfaces like food wrappings and cooking pans have been made with PFAS compounds.

Both PFOA and PFOS have not been manufactured in 10+ years but persist in the environment due to the many everyday sources of contamination. Because they are so widely used, they can now be found in the environment around the world, including in the air, water, and soil. Since they break down slowly, they can build up in people and animals who are heavily exposed through their environment and have even started to show up in our drinking water

Why are PFAS harmful and are they regulated?

Because there are so many PFAS chemicals, it’s hard for scientists to pinpoint which ones are the biggest concerns and at what levels they become dangerous to human health. A study by the Centers for Disease Control and Prevention’s National Health and Nutrition Examination Survey (NHANES) found PFAS compounds in the blood of 97% of Americans. Learn more here.

Not a lot is known about the health effects of exposure to PFAS compounds, but current research suggests that exposure to high levels can lead to many different types of health concerns such as interference with hormones, decreased fertility in women, developmental delays in children, and increased risks for certain types of cancers to name a few. Scientists are still trying to determine at what levels various PFAS compounds become toxic and if exposure at different points in your lifetime can change the impact these chemicals have on our bodies. 

The EPA does not yet have enforceable standards on PFAS compounds although PFOA and  PFOS have been included in proposed updates to drinking water regulations. EPA has issued health advisories for these compounds. 

What about PFAS in the Anacostia?

To get a better understanding of the prevalence of these chemicals, Waterkeepers all over the country collected and tested samples in their watershed in 2022. Across all U.S. waters tested, 83% of samples showed detection of a PFAS compound and some showed very high concentrations of PFAS – up to thousands of parts per trillion. Maryland was found to be one of the states with the highest number of PFAS detections. Learn more about the Waterkeeper Alliance study here.

We sampled six locations throughout the watershed:

  1. Anacostia Mainstem alongside Kingman Island, which was chosen as our baseline site.
  2. Kingman Lake, which is close to RFK stadium and astroturf fields which are a known source of PFAS.
  3. Pepco Bay on the Anacostia Mainstem, which has a history of contamination at this site.
  4. Quincy Run, which is downstream of a recycling center and has a history of poor water quality.
  5. Long Branch, a tributary of Sligo Creek, which is downstream of an artificial turf field at a local high school. 
  6. Northwest Branch, which is downstream of a site where neighborhood residents raised pollution concerns.

The ARK results found measurable levels of 8-10 different PFAS compounds in all six samples collected. The EPA health advisory limit for PFOA is for concentrations above 0.004 parts per trillion (ppt). All six sites exceeded this limit with counts ranging from 3.5 to 8 ppt. Likewise, PFOS has an EPA health advisory for concentrations above 0.02 ppt. ARK results for PFOS also exceeded this limit, ranging from 4.7 to 7.7 ppt. 

With these high levels of PFAS found in our waterways, we need more regulations to prevent further contamination and prioritize remediation. We hope to expand our monitoring to new sites this year to gain a bigger picture of PFAS in the Anacostia Watershed.

Updates and Links to Learn More:

For information on the EPA’s PFAS Strategic Roadmap, opportunities for public comment, and more, check out

Washington Post Article, JULY 9 2023: PFAS  widely used in DC for decades have caused widespread contamination by traveling into surface water and soil. DC files lawsuit. 

EPA 2nd Annual Report, DEC 2023: EPA’s second annual report on PFAS progress highlights milestones reached in protecting people and communities from harmful PFAS. Key accomplishments include actions to prevent PFAS from entering the environment and holding PFAS polluters accountable.