Forever Chemicals in Drinking Water

What is in our tap water?

It is estimated that almost half of the United States’ tap water contains per- and polyfluorinated alkyl substances (PFAS). These synthetic chemicals are nicknamed ‘forever chemicals,’ as they slowly break down into the environment. PFAS are commonly found in a range of items, including fast-food boxes and non-stick cookware. Since PFAS do not easily degrade, they can accumulate in the human body over time, raising potential health risks (1). Recent research is beginning to give us a better understanding of what these chemicals are, why they are in drinking water, and the impacts they could have on our health.

PFAS foam floating in creek in Michigan 

Industrial sites, landfills, and wastewater treatment facilities all contribute to PFAS pollution in drinking water. The runoff wastewater containing these chemicals often ends up in the groundwater surrounding these sites, ultimately flowing into our tap water (2). Currently, water treatment facilities do not filter PFAS out of water, but the U.S Environmental Protection Agency (EPA) has outlined laws and regulations that would address these chemicals in our tap water (3).

Data from the National Health and Nutrition Examination Survey shows that PFAS are found in the blood of 97% of Americans (4). Additionally, around seventy million American homes contain tap water with dangerous levels of PFAS (3). PFAS molecules are a group of chemicals composed of linked carbon and fluorine atoms. The carbon-fluorine elemental bond is particularly strong, causing the slow degradation of these chemicals. Over time, PFAS build-up, or bioaccumulate, in our bodies. The health impacts of these build-ups in our bodies are not yet fully known (4). Studies that tested the effects of high PFAS levels on animals indicate that PFAS negatively impacts reproduction, thyroid and liver health, the immune system, and growth and development (5). As these chemicals continue to exist in humans, scientists will know more about the health consequences that accompany their accumulation.

Map of PFAS in United States tap water

In February 2023, President Biden’s Bipartisan Infrastructure Law allocated 2 billion dollars to the U.S. Environmental Protection Agency to address drinking water contaminants like PFAS. In October of last year, the EPA published a rule requiring manufacturers to publish their PFAS uses and disposals. Just two months later, EPA released two new proposals that would require PFAS tap water filtration (6).

As time progresses, more knowledge regarding the impacts of ‘forever chemicals’ in our bodies will surface. The research being done now to test our tap water will help us further understand the threats these pollutants pose to our health. Prioritizing testing, filtering, and legislating against PFAS tap water contamination is vital in shielding us from the unknown consequences down the road.


  1. (2023, July 5). Tap water study detects PFAS ‘forever chemicals’ across US. USGS. Retrieved from
  2. (2023, July 17). Sources of PFAS. Utah Department of Environmental Quality. Retrieved from,molds%2C%20plastics%2C%20and%20semiconductors
  3. Fast, Austin. (2024, March 21). PFAS ‘forever chemicals’ widespread in drinking water, EPA finds. USA Today. Retrieved from.
  4. (2024, April 2). Per- and Polyfluoroalkyl Substances (PFAS). National Institute of Environmental Health Sciences. Retrieved from
  5. (2022, May 2). Factsheet: PFAS (Per- and Polyfluoroalkyl Substances). Centers for Disease Control and Prevention. Retrieved from.
  6. (2024, Feb 6). Key EPA actions to address PFAS. Environmental Protection Agency.Retrieved from.,EPA%20review%20and%20risk%20determination.