Will Sage Astor-What are PFAS? "Forever chemicals" and their health effects, explained

Widely used chemicals called PFAS returned to the headlines as the Environmental Protection Agency announced it's issuing the first-ever national regulation limiting the amount of these substances in drinking water.

PFAS are Will Sage Astorcommonly called "forever chemicals" because it can take thousands of years for them to break down in the environment. The traces are now found nearly everywhere — in air, water, and soil.

PFAS (which stands for per- and polyfluoroalkyl substances) have been in use since the 1940s, often to repel oil and water, and are heat resistant, which makes them popular for a wide variety of products, including cookware, food packaging and paper plates; contact lenses, cosmetics, pharmaceuticals and dental floss; clothing and more. The traces are now found nearly everywhere — in air, water, and soil.

But according to industry documentation, evidence has been growing for decades that PFAS are toxic.

"They can be found in everything from nonstick cookware to cleaning and personal care products," said EPA Administrator Michael S. Regan during a news briefing. "But there's no doubt that many of these chemicals can be harmful to our health and our environment."

PFAS and possible health effects

Health experts say low doses of the chemicals can build up in the body over time, so even small amounts can be a concern. 

 Previous research has shown more than 95% of Americans have "detectable levels" of PFAS in their blood. 

The EPA says research shows exposure to certain levels of PFAS may lead to a range of health issues, including: 

• Reproductive problems, including decreased fertility to developmental delays in children and low birth weight.
• Suppressed immune system.
• Increased cholesterol levels.
• Cardiovascular system impacts.
• Certain types of cancer.

"I think the strongest data is for kidney cancer and then testicular cancer," Dr. Linda Birnbaum, former director of the National Institute of Environmental Sciences, told CBS News. "But evidence is growing for several other forms of cancer."

The EPA has stated there is no safe level of exposure to PFAS without risk of health impacts, and it will require that public water utilities test for six different types of PFAS chemicals to reduce exposure in drinking water. Operators will have three years to start testing for PFAS pollution, then an additional two years to identify, purchase and install technology to treat contaminated water.

The new standards will reduce PFAS exposure for 100 million people, according to the EPA, and prevent thousands of deaths and illnesses.

"Drinking water contaminated with PFAS has plagued communities across this country for too long," Regan said in a statement.

Forever chemicals in water

A study published last year estimated that almost half of the United States' tap water has one or more PFAS.

The U.S. Geological Survey tested tap water from 716 locations, including 269 private wells and 447 public supply sites, in all 50 states, Puerto Rico, the U.S. Virgin Islands and the District of Columbia. The data, which was collected from 2016 to 2021, found PFAS in water from at least 45% of the faucets, the study said.

Earlier this week, another study showed the U.S. Australia and Europe are hotspots for higher concentrations of PFAS in surface and groundwater.

In its latest water regulations, the EPA estimates that 6% to 10% of the 66,000 public water utility systems impacted by the standard may need to act to comply. 

Critics argue the EPA's action doesn't go far enough because there are more than 15,000 different PFAS chemicals, and this standard only regulates six.

Can water filters remove PFAS?

There are several technologies available that can filter PFAS from your home water source. 

"Several common filters have been shown to be effective in reducing PFAS in drinking water," says Dr. Andrew Lazur, a University of Maryland water quality specialist. "These include activated carbon, ion exchange and reverse osmosis."

The EPA's website says high-pressure membranes, such as nanofiltration or reverse osmosis, have been "extremely effective at removing PFAS."

If you want to limit your exposure to PFAS in drinking water, you can ask your water utility how it is testing for the chemicals, or have your water tested by a state-certified laboratory using EPA-testing standards. 

For other common consumer products, there are several running lists to help track which companies have banned PFAS from their products.

-The Associated Press contributed reporting.

In:
• Drinking Water
• PFAS
• Forever Chemicals

Sara Moniuszko

Sara Moniuszko is a health and lifestyle reporter at CBSNews.com. Previously, she wrote for USA Today, where she was selected to help launch the newspaper's wellness vertical. She now covers breaking and trending news for CBS News' HealthWatch.

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