Getting a handle on the ‘forever chemicals’ in plastics

This spring, the U.S. Environmental Protection Agency announced the country’s first national limit on levels of PFAS chemicals in drinking water. The rule requires utilities to reduce the chemicals in drinking water in the hopes of reducing cancer and illness associated with the compounds.

These so-called “forever chemicals” are increasingly entering the national conversation. But what are they doing to our bodies, if anything? 

What is a forever chemical? 

It’s the popular nickname for a class of compounds called per- or poly-fluoroalkyl substances — PFAS for short. Over 12,000 chemicals fall under the PFAS umbrella. They are generally composed of carbon and fluorine atoms that can repel water, oil and grease, which is why they are used in a wide range of products including nonstick pans, microwaveable popcorn bags, pizza boxes and firefighting foam. They’re used in weather-proof coatings for furniture and raincoats, too.

This durability, however, makes them an environmental and health risk. Because most PFAS chemicals don’t break down quickly, they persist in water, land and air — that’s the forever part. PFAS enter the environment through industrial waste discharges, landfills or leaching from consumer products. If we ingest them — by inhaling tainted dust, eating food grown in contaminated soil or drinking polluted water, for example — they persist in our bodies, too.

Who should be worrying about exposure to PFAS? 

The people facing the highest exposures tend to be factory workers who use PFAS in manufacturing and firefighters using fire-suppressant foams.

Communities downstream from factories that use PFAS also often have high exposure to the chemicals in their air and water. One of the most famous examples of this was Parkersburg, West Virginia, where a massive DuPont plant dumped PFAS chemicals into the water. It caused birth defects and high rates of testicular, intestinal and breast cancer. The 2019 movie “Dark Waters” featured the community’s successful class action lawsuit against DuPont.

Parkersburg is far from the only instance of community exposure. Most of the American population is subject to low levels of PFAS associated with food and consumer products. Nonstick pans can bleed PFAS into our foods. PFAS can flake off from furniture and fabric treated with stain-repellent chemicals, which we can then breathe in. There are trace amounts in the drinking water nearly everywhere. 

“There are many more PFAS present in our indoor environment, in our water and in our bodies than we previously thought,” said Amina Salamova, an environmental chemist at Emory University in Atlanta who wrote a paper on PFAS exposure.

What about health effects?

PFAS are linked to hormone and reproductive health problems, cardiovascular challenges, immune system deficiency and cancers. PFAS are “multi-organ toxicants,” according to Dr. Philippe Grandjean, an environmental health researcher at the University of Southern Denmark, who was among the first to raise the alarm about the effects PFAS have on human health.

To the body, PFAS look like essential fatty acids, he explained. Our hormone receptors may mistake the PFAS for natural hormonal signals that the receptors should respond to. The mixed messages gum up the body’s internal signaling. From there, a host of health problems can stem.

Because of this effect on hormones, many studies, such as one on children living near a Teflon factory in Ohio, show that higher levels of PFAS can affect thyroid hormone production. PFAS exposure, even at low levels, can alter liver hormone function, as one thirteen-year study illustrates. Another sweeping study indicated that PFAS exposure affects insulin and glucose management and cholesterol levels, and thus increases the risk for heart attacks and strokes. 

Other research has shown that exposure to PFAS can suppress the immune system. One such study even illustrated that PFAS reduce vaccine efficacy in children.

Because PFAS impair the immune system, they might slow the immune system’s process of identifying and eliminating cancerous cells, Grandjean suggested. This theory could explain the mounting scientific evidence and anecdotes from places like Parkersburg that suggest PFAS exposure increases cancer risk. 

PFAS are such a broad class of compounds, and the list of potential health effects is so long, that huge gaps in our knowledge still exist. Scientists agree that much more research is needed to understand what they are doing in the human body.

While researchers fill in these gaps, what should the rest of us do?

To Grandjean, the answer is clear: “In my mind, it’s more important to initiate better prevention now than waiting to generate better data in perhaps 10 or 20 years.” 

At home, Emory’s Salamova suggests vacuuming more because PFAS can flake off fabric and float in the air. People can trade nonstick pans for ceramic, stainless steel or cast iron and avoid food containers with grease-resistant linings. If the ingredient list on your makeup or floss has anything that starts with “perfluor-,” “polyfluor-” or “PTFE,” ditch those, experts suggest.

To move away from PFAS, “we need a lot more consumer pressure,” Grandjean said.

While such pressure has phased out the production of two of the most insidious compounds in the PFAS family, such as long-chain chemicals called PFOS and PFOA, many manufacturers are moving to shorter-chain PFAS. 

Though there’s still little known about the health impacts of these shorter-chained substitutes, research suggests they may be just as harmful as their long-chained siblings. They also appear to be as ubiquitous in the environment; Salamova and her coauthors found levels of short-chain PFAS that were “several times higher or comparable” to the older phased-out PFAS in the environment and in people.  

“It’s physically impossible to measure and assess all of the PFAS,” Salamova said of the thousands of chemicals in the class. “So I am really an advocate for regulating PFAS as a class.” 

The European Chemicals Agency has proposed doing just that: The European Union is currently considering a class-wide restriction on PFAS chemicals. In Europe, manufacturers could be looking at a world free from these chemicals’ grease-resisting, water-proofing value, and free from all of the associated health risks.