More than 6 million Americans use water contaminated with toxins linked to cancer, according to a new study by researchers from the Harvard T.H. Chan School of Public Health and the Harvard John A. Paulson School of Engineering and Applied Sciences.
The authors of the study found that the hazardous chemicals — polyfluoroalkyl and perfluoroalkyl substances — exceed federally recommended safety levels in some drinking water supplies.
Xindi Hu, the study’s lead author and a doctoral student at Harvard, noted in a statement that the number of Americans drinking water with the toxins might be even higher because data isn’t available for large portions of the country.
“For many years, chemicals with unknown toxicities, such as PFASs, were allowed to be used and released to the environment, and we now have to face the severe consequences,” Hu said. “In addition, the actual number of people exposed may be even higher than our study found, because government data for levels of these compounds in drinking water is lacking for almost a third of the U.S. population — about 100 million people.”
The researchers examined more than 36,000 water samples collected across nation. Seventy-five percent of the contaminated water they found came from 13 states: California, New Jersey, North Carolina, Alabama, Florida, Pennsylvania, Ohio, New York, Georgia, Minnesota, Arizona, Massachusetts and Illinois. According to their findings, the highest levels of contaminants “were detected in watersheds near industrial sites, military bases, and wastewater-treatment plants.”
“These compounds are potent immunotoxicants in children and recent work suggests drinking-water safety levels should be much lower than the provisional guidelines established by EPA,” Elsie Sunderland, the senior author of the study and an associate professor at Harvard said in a statement.
The study, published Aug. 9, coincides with an ongoing water crisis in Flint, Michigan.