Nearly half of tap water in the United States contains PFAS, a class of chemicals linked to serious health problems. In April, the Environmental Protection Agency announced that municipal utilities will be required to detect and remove PFAS from drinking water for the first time.
Here's what you need to know.
What are PFAS?
In 1938, a young chemist working on refrigerants for Dupont accidentally discovered a new compound that was remarkably resistant to water and grease, a finding that would lead to the creation of the Teflon brand of nonstick cookware.
Today, there are nearly 15,000 per- and polyfluoroalkyl substances, collectively called PFAS, according to a database maintained by the EPA
The common connection is that they have a special bond of carbon and fluorine atoms, making them incredibly strong and resistant to heat, water, oil and dirt. For that reason, PFAS is used on everyday items as diverse as microwave popcorn bags, water-repellent clothing and stain-resistant carpets. PFAS are also found in firefighting foam, cosmetics, shampoos, toys and even dental floss.
Where are PFAS?
Everywhere, including drinking water. The indestructible nature that makes PFAS useful in some products also makes them harmful to human health. The chemicals are virtually indestructible and do not break down completely as they accumulate in the environment and the human body.
The chemicals are so ubiquitous that they can be found in the blood of almost everyone in the country. A recent government study found PFAS chemicals in almost half of the country's tap water. A global survey of more than 45,000 water samples around the world found that approximately 31 percent of groundwater samples tested were not near an obvious source of contamination. had considered PFAS levels harmful for human health.
What does PFAS do to the body?
According to the EPA, PFAS exposure can cause damage to the liver and immune system and has also been linked to low birth weight, birth defects and developmental delays, as well as an increased risk of some prostate, kidney and testicular cancers. New research published this past year has found links between PFAS exposure and a delay in the onset of puberty in girls, leading to a higher incidence of breast cancer, kidney disease and thyroid disease; a decrease in bone density in teenagers, which can potentially lead to osteoporosis; and an increased risk of type 2 diabetes in women.
Why hasn't the EPA regulated PFAS in water sooner?
Many environmentalists argue that PFAS contamination should have been addressed long ago.
“For generations, PFAS chemicals slid off every federal environmental law like a fried egg from a Teflon pan,” said Ken Cook, president and co-founder of the Environmental Working Group, a nonprofit organization.
Activists blame chemical companies for hiding evidence of PFAS dangers for decades, lawsuits show a peer-reviewed studypublished in the Annals of Global Health, from previously classified industry documents.
The new EPA rule requires utilities to reduce PFAS in drinking water to near-zero levels.
How do I get rid of PFAS?
Not easy. In homes, filters attached to faucets or in pitchers generally do not remove PFAS substances. Under-sink reverse osmosis systems have been shown to remove most, but not all, PFAS in studies conducted by scientists at Duke University and North Carolina State University.
Municipal water systems can install one of several technologies, including carbon filtration or a reverse osmosis water filtration system that can reduce the levels of the chemicals.
Now that limits have been set, when will PFAS disappear from tap water?
It could take years. Under the rule, a water system has three years to monitor and report PFAS levels. If levels then exceed the EPA's new standard, the utility will have another two years to purchase and install filtration technology.
But trade groups and local governments are expected to take legal action against the ordinance, possibly even delaying it before a court issues a final ruling. And if former President Donald J. Trump were to retake the White House in November, his administration could also roll back or weaken the rule.