More than 6 million Americans are drinking tap water contaminated with carcinogenic industrial chemicals, according to a new study from researchers at Harvard.
Unlike the water crisis in Flint, Michigan, which was linked to a specific cause and confined to one area, the presence of toxic industrial chemicals is a problem across the U.S., researchers say.
A map published along with the study showed the continental U.S. peppered with zones where drinking water is contaminated, including large swaths of populous states like California, Florida and New York, as well as all of New Jersey.
"Poly- and perfluoroalkyl substances (PFASs) make up a large group of persistent anthropogenic chemicals used in industrial processes and commercial products over the past 60 years," researchers wrote. "Widespread use and extreme resistance to degradation have resulted in the ubiquitous presence of these compounds in the environment."
The chemicals are used in a range of applications, and are commonly found near civilian airports, firefighter training facilities, military bases and industrial facilities. Ground water and surface water near such sites are regularly contaminated, the scientists found -- but the chemicals are so pervasive that they've also contaminated crops, livestock and wildlife in many areas.
Until some of the chemicals were banned, they were also used in consumer products, like food wrappers, pots and pans, and clothing, scientists said.
“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,” lead author Xindi Hu, a doctoral student at the Harvard T.H. Chan School of Public Health 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.”
Compounding the problem is the fact that most wastewater treatment systems can't remove the carcinogenic chemicals, according to the researchers. And while they found higher-than-acceptable levels of the chemicals in the drinking water supplies of 33 U.S. states, the scientists say the government should lower the threshold of what's considered acceptable contamination, because even "safe" drinking water could contain damaging levels of toxins.
“The EPA advisory limit ... is much too high to protect us against toxic effects on the immune system,” study co-author Dr. Philippe Grandjean of the Harvard School of Public Health told the Charleston Gazette-Mail. “And the available water data only reveals the tip of the iceberg of contaminated drinking water.”