Communities across the United States that have been exposed to drinking water contaminated with per- and polyfluoroalkyl substances (PFAS) are experiencing a higher incidence of certain cancers, according to a recent study conducted by researchers at the Keck School of Medicine of USC. The study, published in the Journal of Exposure Science & Environmental Epidemiology, is the first to explore the relationship between cancer and PFAS contamination in drinking water in the U.S.
PFAS are synthetic chemicals found in a variety of consumer products, such as furniture and food packaging, and have been detected in approximately 45% of drinking water supplies in the country. These chemicals are known to accumulate in the body over time and have been linked to various health issues, including kidney, breast, and testicular cancers.
To gain a better understanding of the association between PFAS and cancer risk, researchers at the Keck School of Medicine conducted an ecological study using large population-level datasets. The study revealed that counties with PFAS-contaminated drinking water had a higher incidence of certain types of cancer between 2016 and 2021, with differences observed between male and female populations. Overall, PFAS in drinking water are estimated to contribute to over 6,800 cancer cases each year based on data from the U.S. Environmental Protection Agency (EPA).
Lead researcher Dr. Shiwen (Sherlock) Li emphasized the importance of further research to investigate the specific links between PFAS and different types of cancer. The findings also underscore the need for stricter regulations on PFAS levels in drinking water. While the EPA plans to monitor six types of PFAS in drinking water starting in 2029, Dr. Li suggests that more stringent limits may be necessary to safeguard public health.
The study compared comprehensive datasets on cancer cases and PFAS levels in drinking water from national databases. Factors such as age, sex, socioeconomic status, smoking rates, and exposure to other pollutants were taken into account to analyze the relationship between PFAS contamination and cancer incidence. Counties with elevated levels of PFAS in drinking water showed higher rates of digestive, endocrine, respiratory, and mouth and throat cancers, with incidence increases ranging from 2% to 33%.
Males living in areas with contaminated drinking water had a higher incidence of leukemia, urinary system, brain, and soft tissue cancers, while females had a higher incidence of thyroid, mouth and throat, and soft tissue cancers. The researchers estimated that PFAS contamination contributes to over 6,800 cancer cases annually, highlighting the personal and financial toll of these cases.
The findings of this study suggest the need for individual-level research to determine causality and explore the biological mechanisms involved. From a regulatory standpoint, the results support the call for more stringent monitoring of PFAS levels in drinking water to protect public health. The research was conducted as part of a collaboration between the Southern California Environmental Health Sciences Center and the USC Norris Comprehensive Cancer Center at the Keck School of Medicine.
For more information on this study, you can refer to the Journal of Exposure Science & Environmental Epidemiology. This research sheds light on the potential risks associated with PFAS contamination of drinking water and emphasizes the importance of continued efforts to regulate these harmful chemicals.
