According to a recent study, PFAS is a possible source in the US and is present in at least 45% of drinking water close to urban areas. Since these substances have been connected to a number of cancers, determining if they are present in drinking water can aid in biomonitoring and preventative initiatives.
The first study to look at the connection between drinking water PFAS contamination and cancer rates in the US is from USC’s Keck School of Medicine. It was discovered that the incidence of some cancers can increase by up to 33% in areas exposed to drinking water tainted with PFAS.
To learn more about PFAS and cancer risk, researchers used extensive population statistics to conduct an ecological study. Cancer rates were greater in US counties with drinking water contaminated with PFAS between 2016 and 2021, with differences by sex.
According to new data from the US Environmental Protection Agency (EPA), PFAS in drinking water are thought to be responsible for more than 6,800 cancer cases annually.
The study’s first author, Shiwen (Sherlock) Li, PhD, a postdoctoral researcher in the Keck School of Medicine’s Department of Population and Public Health Sciences, stated, “These findings allow us to form an initial conclusion concerning the link between some uncommon malignancies and PFAS.” This implies that it would be worthwhile to conduct more thorough and specialized research on each of these connections.
Researchers evaluated two sizable datasets—one for all reported cancer cases and one for PFAS levels in drinking water throughout the United States—in order to better understand the relationship between PFAS exposure and cancer. They used PFAS levels data from 2013 to 2024 and cancer case data from 2016 to 2021.
Age, sex, socioeconomic level, smoking prevalence, obesity, urbanization, and other pollutants were all taken into account by the researchers. Using the EPA’s suggested cutoffs for each form of PFAS, they compared the cancer rates in each county to the levels of PFAS in drinking water.
Cancers of the mouth, throat, endocrine system, and digestive tract were more common in counties where PFAS levels were higher than the advised upper limit. Perfluorobutanesulfonic acid (PFBS) was associated with the largest increase in cancer incidence, which varied from 2% to 33%.
Males in counties with PFAS-contaminated drinking water were more likely than those in uncontaminated areas to develop leukaemia, brain, soft tissue, and urinary system malignancies. Soft tissue, mouth, throat, and thyroid malignancies were more common in women. Recent EPA data indicates that an estimated 6,864 cancer incidences annually are attributed to PFAS pollution.
Li clarified that figuring out how many cancer cases are connected to PFAS aids in estimating the financial and human costs. These results show previously unknown links between PFAS and uncommon malignancies. To ascertain if the connection is causative and investigate the molecular mechanisms at play, individual-level research is required.
Less-studied PFAS require greater monitoring, and regulators should take into account other PFAS that may not be rigorously controlled yet. The results also indicate that PFAS levels should be limited and that proposed rules may not go far enough.
-Raja Aditya
