'Forever Chemicals' Present in Homes, Humans, and Drinking Water, Study Finds

October 17, 2023
A woman filling a cup with water

By Rob Spahr

A newly released study led by researchers from Emory University’s Rollins School of Public Health was one of the first to find an emerging class of “forever chemicals” in the homes, drinking water, and bodies of United States residents.

There are thousands of per- and polyfluoroalkyl substances (PFAS), also known as “forever chemicals,” but scientists and health care experts only have sufficient data on the potential human-health impacts of a relative handful of these man-made chemical compounds. Most of the existing research has focused on the legacy and longer-chain PFAS, such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), which were found to be toxic and have been banned for many years. 

However, an Emory-led study published Wednesday in Environmental Science & Technology found that an emerging class of ultrashort- and short-chain PFAS – meant to serve as replacements for the already banned PFAS compounds – are now being found in elevated levels in U.S. residents, as well as their homes and water supplies.  Ultrashort- and short-chain PFAS have fewer carbons and are more mobile, particularly in water, than legacy PFAS.

Because little is known about the sources and potential health impacts of these newer compounds, the Emory researchers say the extent of ultrashort PFAS exposure discovered during this study highlights the urgent need for more research and risk assessments. 


  • More than 300 samples from the homes, drinking water, blood, and urine of 81 participants were studied.
  • Elevated levels of ultrashort- and short-chain PFAS were found in most of the samples of household dust, drinking water, and participants’ blood and urine.
  • The levels of ultrashort PFAS found in household dust and drinking water were several times greater than the levels of legacy PFAS. In serum samples, the levels were either higher or comparable.
  • Scientists do not yet know the source of these compounds or their potential impact on the health of humans and/or the environment. This means there is also not enough information yet on what precautions, if any, people can take to reduce their exposure.


Amina Salamova, PhD, study co-author and assistant professor in the Gangarosa Department of Environmental Health:

“These results were very concerning, especially considering the concentration of these compounds we found were much higher concentrations than those of legacy PFAS. So, it is very important to investigate the toxicity and health effects of these compounds. Because they are also more mobile, so they can get transported to remote areas – through water, for example – which can increase the risk of exposure.”

Stephanie Eick, PhD, study co-author and assistant professor of environmental health and epidemiology:

“The biggest takeaway is that these new, short-chain PFAS – which have not really received much attention yet – are everywhere. These chemicals also haven’t really even been considered as potential public health problems yet, but they are highly prevalent in people and in dust samples from our homes.”