The chemicals called “PFAS” have been in the news a lot lately — like a recent report reaffirming links between PFAS and some health issues. There's also earlier revelations that contaminated compost and fertilizer may have led to PFAS in water supplies.
So, what are these chemicals, anyway? And should we be worried about them? Here’s what you need to know:
What are PFAS?
There are around 4,700 chemicals in the PFAS family, and they all have two things in common:
- They’re all man-made.
- They contain chains of carbon and fluorine.
The bond between carbon and fluorine atoms is one of the strongest in nature. That means that PFAS chemicals don’t degrade easily; they stick around in the human body and the environment for a long time, and are very stable in water. That’s why some people call them “forever chemicals.”
Where do they come from?
PFAS chemicals were invented in the 1930s, and found to have some useful qualities for consumer products because they repel oil, water and grease. Companies used these chemicals in many common items, like paper food packaging (think microwave popcorn bags and pizza boxes), stain-proof rugs, waterproof clothing, some types of dental floss and nonstick cookware.
The two PFAS chemicals you’re most likely to hear about are perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). Neither of them are made in the United States any longer — manufacturers started voluntarily phasing them out in the early-2000s — but because they were manufactured here for decades, they remain the most widespread in the environment, most-studied and best understood. Manufacturers from other countries still produce PFOS and PFOA, and can ship products made with them into the U.S.
U.S. manufacturers have replaced PFOA and PFOS with other members of the PFAS family. The effects of these next-generation PFAS chemicals are not as well understood.
The bottom line is there are still PFAS chemicals in the everyday products we buy, and also lots of them sticking around in our water.
What is the effect of PFAS chemicals on health? And how do we know?
Because these chemicals have been used in many consumer products for many decades, most people have been exposed to them. The chemicals probably enter our bodies through the food we eat, like microwave popcorn, food in takeout containers or fish from contaminated water.
Some people are exposed through highly contaminated drinking water, according to Laurel Schaider, a research scientist with the Silent Spring Institute. People can also inhale PFAS-contaminated air or dust. According to the CDC, studies have shown that only a small amount of PFAS can be absorbed through your skin. Studies estimate that 98% of Americans have detectable levels of PFAS in their blood.
A 2022 report from the National Academies offered the first comprehensive summary of the links between PFAS levels in the blood and specific health concerns. The report said there is "sufficient evidence" of association between PFAS exposure and kidney cancer in adults, decreased immune response in adults and children, high cholesterol in adults and children, and decreased infant and fetal growth. The report recommended blood tests and medical monitoring for people likely to have high exposure to PFAS.
The effects of low-level exposure are also less understood, says Schaider, who is currently studying PFAS exposure in the towns of Hyannis and Ayer. And scientists are less certain about the health effects of newer PFAS compounds that replaced PFOS and PFOA
Despite the remaining uncertainty, scientists have found that PFAS chemicals affect “every major organ in the human body,” says Elsie Sunderland, a PFAS researcher at the Harvard T.H. Chan School of Public Health. “So that is scary for me.”
But, she says, since PFOS was phased out of production around the year 2000, blood levels have dropped dramatically. “If you stop producing it, yes, you can still find it,” she says. “But we also saw a very fast and dramatic reduction in both environmental samples and people’s blood.”
“If you stop producing it, yes, you can still find it.”Elsie Sunderland
How do these chemicals get into drinking water?
PFAS chemicals were widely used in firefighting foams on military bases, airports and firefighting training facilities. They are also found in landfills when products containing PFAS break down, and in fertilizer made from human waste or sewage. All these sources can contaminate nearby drinking water supplies.
Estimates about the extent of contaminated drinking water vary widely, based on testing methods and sensitivity. The Environmental Working Group, a consumer-education nonprofit, estimates that 1,500 drinking water systems across the country may be contaminated, affecting 110 million Americans.
Northeastern University also maintains an interactive map of PFAS contamination in the U.S.
How do I know if my drinking water is contaminated? What do I do if it is?
Massachusetts has required PFAS testing of drinking water since 2020. As of July, 2022, most of the public water systems in Massachusetts had been tested for the six most common PFAS compounds, and water supplies in 93 communities have had at least one test result over the legal limit. While some communities have been able to switch to alternate water systems or turn off contaminated wells, many are still searching for long-term solutions.
You can search for test results in Massachusetts communities by going to this website and typing in "PFAS6" under "chemical name."
Outside Massachusetts, a good place to start is the Environmental Working Group’s Tap Water Database. Enter your ZIP code and see if there are any contaminants in your home water (you may want to double check with your supplier if any numbers are concerning).
If you want to decrease the PFAS chemicals in your water, Phil Brown, a PFAS researcher at Northeastern, suggests installing a home water filter that uses activated carbon or a reverse osmosis system.
“Obviously we want to protect ourselves and our families,” he says, “but we also want to focus on getting cities and states and the federal government to their job.”
How do I avoid eating PFAS with my food?
“Don’t eat microwave popcorn — that’s an easy one,” Sunderland says. She also says to avoid food packaging and take-out boxes when possible, opting instead for fresh food in reusable containers.
Should I stop using nonstick cookware?
Experts are divided on nonstick cookware. Some say don’t use it at all, while others say it’s OK as long you don’t use it on high heat, and the coating isn’t flaking off.
What else can I do to limit my exposure to PFAS chemicals?
Skip the stain-resistant carpets and upholstery. Use uncoated dental floss, or at least floss coated with natural wax. Sunderland also notes that some companies, like Ikea, Lowe’s and Columbia Sportswear, are starting to phase PFAS chemicals out of some of their products, so you can look for items that are PFAS-free. The Green Science Policy Institute’s list of PFAS-free products is a good resource. The Silent Spring Institute offers a free mobile app called Detox Me, which includes a buying guide.
What is the federal standard for PFAS in drinking water?
There are currently no federal regulations for PFAS in drinking water. However, in June, 2022, the Environmental Protection Agency issued nonbinding health advisories setting health risk thresholds for the two most common PFAS chemicals — PFOA and PFOS — to near zero. Schaider said that the federal government is expected to release draft PFAS regulations in late 2022 or early 2023.
There is also a question about whether the EPA may list PFOS and PFOA as hazardous substances under the Superfund law, which would help communities clean up contamination, and also recover costs.
What’s the Massachusetts standard?
Massachusetts released regulations for PFAS limits in drinking water in September, 2020. The rule establishes a limit of 20 parts per trillion for the sum of six PFAS compounds, including PFOS and PFOA. Managers of all public water systems in the state are required to test for these six compounds and take action when they detect PFAS levels above the limit.
What else is Massachusetts doing to manage PFAS?
In 2020, the Massachusetts legislature also created the PFAS Interagency Task Force to investigate water and ground contamination across the Commonwealth. The Task Force released their final report in 2022.
In May, 2022, Attorney General Maura Healey sued 13 manufacturers of PFAS chemicals used in firefighting foam for causing millions of dollars in damages to communities across Massachusetts.
Is there any way to really, truly, get rid of these things?
“One of the few things that will get rid of PFAS are very high temperatures,” Schaider says.
Water-treatment facilities, for instance, will often send their PFAS-infused filters to incinerators for disposal. Sunderland says that if the incineration isn’t complete, there is concern that the chemicals and their precursors will be released back into the environment.
The Department of Defense is researching other ways to deal with the chemicals.
This article was originally published on November 08, 2019.