How PFAS Can Harm Your Health

Even at low levels, these chemicals have been linked to kidney disease, lowered immunity in kids, and a variety of other health concerns

Illustration of a child and a hospital patient with a beaker in between them spreading PFAs Illustration: Lacey Browne/Consumer Reports

Recent Consumer Reports tests of more than 100 food packaging products from U.S. restaurants and supermarkets found dangerous PFAS chemicals in many of the products, including paper bags for french fries, wrappers for hamburgers, molded fiber salad bowls, and single-use paper plates. 

Previous CR tests found PFAS—per- and polyfluoroalkyl substances—in drinking water and bottled water.

That’s concerning, as growing research documents that PFAS, which are added to many materials to make them resistant to grease, water, and stains, have led to environmental contamination around the globe and raised questions about their health risks when they accumulate in our bodies.

How Humans Are Exposed to PFAS

One of the main concerns about PFAS is how long they last. In fact, they are often called “forever chemicals” because they break down extremely slowly, if ever.

That persistence, combined with the many products that now contain PFAS, means that there are many ways the chemicals can enter the environment and eventually reach humans, too. 

More on PFAS

Consider, for example, the production of food packaging with PFAS coating. In Maine, wastewater sludge from mills where such products are produced has reportedly been used to fertilize fields where cattle graze. In 2020, the Maine Department of Agriculture, Conservation and Forestry tested milk from dairy farms and found levels of one particular PFAS in a sample from a farm that were more than 150 times higher than state regulations permit.

When food packaging contains PFAS, some of those chemicals can migrate into food. Other products, like stain-resistant carpets, can leave PFAS in household dust and air. 

And finally, once food packaging or other products containing PFAS are thrown away, PFAS can leach out from landfills or spread from incinerators into the environment, where they can contaminate soil, food, water, and air—just like they can when they are first produced. 

People may then eat food containing the chemicals, drink water that contains them, or even breathe the chemicals in.

And a growing number of the chemicals have been linked to a variety of health problems.

PFAS Linked to Many Health Issues

For decades, PFAS manufacturers have had information indicating that the chemicals may harm human health, according to reporting from the Environmental Working Group. But for the first 60 or so years that PFAS were in production, many people thought that potential harms were specific to workers exposed to the chemicals at an industrial scale, not the general public.

Then, in 1998, a West Virginia farmer named Wilbur Tennant started raising concerns about the effects that pollution from a nearby DuPont factory had on his cattle. This helped lead to a class-action lawsuit alleging that this contamination—with the PFAS chemical PFOA, also known as C8—could be affecting the approximately 70,000 people who got water from the same polluted source.

The resulting settlement led to the creation of the C8 science panel, which between 2005 and 2013 assessed links between exposure to PFOA and a number of diseases, and found probable links between exposure and thyroid disease, higher cholesterol levels, kidney and testicular cancer, ulcerative colitis, and pregnancy-induced hypertension. Other research on various PFAS has found links to liver damage and kidney disease.

There are consistent patterns across these chemicals, and the most consistent pattern is that they’re toxic.

Miriam Rotkin-Ellman, senior scientist at the Natural Resources Defense Council

Safety Concerns at Low Levels

Growing research has also shown that health risks can occur even at very low levels. Some of the clearest evidence about that risk comes from an unexpected place: the seemingly pristine Faroe Islands, a group of 18 small, rocky islands midway between Iceland and Norway in the North Atlantic. 

In 2010 and 2011, Philippe Grandjean, PhD, a professor of environmental medicine at the University of Southern Denmark, had been studying children in the Faroes to see whether certain chemicals in the environment could dampen the immune system’s response to childhood vaccines. When he saw a study showing that PFAS could affect animal immune systems, he and colleagues decided to see whether PFAS also affected how children responded to the vaccines.

The results were dramatic. “I fell off my chair,” Grandjean says. “It was very clear these compounds were inhibiting the immune system.”

In 2012, Grandjean and colleagues first published their research showing that higher levels of PFAS in blood samples taken from the children were associated with less effective protection after being vaccinated. 

The findings were alarming not just for the Faroes. Blood PFAS levels among children in the U.S. are comparable, Grandjean says. Follow-up research in other countries has confirmed this effect, and has also shown that children with higher blood levels of PFAS have more infections, he says.

A Toxic Pattern

Still, calculating the exact level of PFAS exposure that causes harm isn’t straightforward, especially since there are thousands of different PFAS, some more toxic than others. Manufacturers have stopped producing a couple of these chemicals in the U.S., as concerns about their impact on health have become more widely known. As that has happened, however, they’ve been replaced by newer chemicals that have not been as thoroughly studied by independent researchers.

Both the Food and Drug Administration and the American Chemistry Council, which represents PFAS manufacturers, argue that we don’t know for sure that newer PFAS are as unsafe as the ones they are replacing. But a growing body of research suggests that many do pose risks, says Miriam Rotkin-Ellman, a senior scientist at the Natural Resources Defense Council. A database of research on more than two dozen different PFAS compiled by a group of scientists who study the chemicals suggests harmful effects associated with many of them.

“There are consistent patterns across these chemicals,” she says, “and the most consistent pattern is that they’re toxic.”

@consumerreports Our tests of 118 food packaging products found #PFAS—‘forever chemicals’ linked to a growing list of health problems—in all kinds of food packaging. Learn more at CR.org/pfaspackaging #foodtok #foodsafety ♬ original sound - Consumer Reports

Head shot image of CRO Health editor Kevin Loria

Kevin Loria

I'm a science journalist who writes about health for Consumer Reports. I'm interested in finding the ways that people can transform their health for the better and in calling out the systems, companies, and policies that expose patients to unnecessary harm. As a dad, I spend most of my free time trying to keep up with a toddler, but I also enjoy exploring the outdoors whenever possible. Follow me on Twitter (@kevloria).