“PFAS are commonly referred to as ‘forever chemicals,’ but the term can be abstract until it hits home: at least 97% of Americans tested have PFAS chemicals in their bodily fluids, according to summaries of research based on national biomonitoring data. It is the same qualities that made these chemicals desirable that also make them persistent in the body, soil, and water.”
Exposure does not depend on one source. PFAS can be introduced into a person’s life through drinking water, food grown or raised in contaminated environments, and a host of products that do not have to reveal whether they contain PFAS.
1. Their chemistry is built to resist breakdown
PFAS are characterized by a carbon chain that is strongly bound to fluorine atoms, making it resistant to heat and degradation. This is one of the key reasons why PFAS persist in the environment and in the body rather than degrading into less persistent forms. There are thousands of synthetic chemicals that fall under the PFAS category.
2. Most exposure routes are mundane, not dramatic
PFASs find their way into the everyday environment through cookware, stain-resistant fabrics, certain cosmetics, food packaging, and fire-suppressing foam. The more ominous threat, however, lies in the regular consumption of contaminated drinking water and food that concentrates PFASs in the soil, feed, or packaging. “The big problem with PFASs is that they are water-soluble,” Jennifer Schlezinger explained. “People are mostly being exposed to them through contaminated drinking water, contaminated food, and then, in part, through products in one’s home.”
3. Drinking water contamination is widespread and uneven
Federal statistics and scholarly analyses have documented PFAS detections in all 50 states in the U.S., with inequities in vulnerability to exposure. The U.S. Geological Survey’s estimate that at least 45% of U.S. tap water contains PFAS has become a benchmark for why the problem cannot be remedied by household choices.
4. The first enforceable national drinking-water limits changed the landscape
In April 2024, the EPA completed its first National Primary Drinking Water Regulation for PFAS, establishing enforceable levels for six PFAS and a hazard index method for certain mixtures. The EPA estimated that the regulation would decrease PFAS exposure for 100 million people. The systems have several years to comply with the standards and have until 2029 to implement reductions at locations where exceedances occur.
5. Food can be a silent delivery system
PFAS can migrate from contaminated soil and water to crops and farm animals, and they can also migrate from food packaging that comes into direct contact with food. Summaries of research studies point to high levels of PFAS in specific foods such as seafood, eggs, and brown rice.
6. Sewage sludge builds a pipeline from cities to farm fields
The treatment of wastewater does not remove PFAS effectively, and as such, these compounds can accumulate in sewage sludge, or biosolids. Industry surveys and estimates related to this matter suggest that close to 70 million acres of agricultural land in the U.S. could be impacted where biosolids are applied, and that 18% of agricultural land in the U.S. could receive biosolids applications.
7. Wildlife effects show what long-term exposure looks like
PFAS have been linked to immune system responses and reproductive damage in animal studies and real-world observations, which reflect how long-term contamination can reorganize health on a population level. This is important for humans because the same waterways and food webs that support wildlife also support human populations.
8. “Replacement” chemicals can create new problems
While some of the older PFAS chemicals like PFOA and PFOS were decreasing in production in the U.S., new chemicals were introduced. GenX-type chemicals are described as having the potential to be more mobile in the environment, meaning that people could be exposed to them at a greater distance from the source. This is a problem that has been seen time and again: one chemical is removed, but the problem of PFAS is not necessarily solved.
9. Military and aviation firefighting foams remain a major legacy source
Aqueous Film-Forming Foam (AFFF) was a factor in contamination surrounding training areas and facilities because it was intended to quickly extinguish fuel fires. Policy reforms have started to limit purchases, such as the Department of Defense’s interim rule that bans the DOD from purchasing AFFF containing more than one part per billion of PFAS, unless an exception is granted. Despite these limitations, legacy contamination can remain in groundwater and soil for several years.
10. Researchers are testing practical ways to reduce PFAS in the body
Interest has shifted from detection and regulation to possible intervention. A pilot study in humans found that a gel-forming fiber supplement taken with meals lowered PFAS concentrations in a small human pilot study using oat beta-glucan samples, according to a report by Schlezinger’s group, published in a peer-reviewed journal. “PFAS easily enter the body, but the issue is that we can’t degrade them, and we can’t remove them from the body,” she explained. “Something I always tell my toxicology students is that a fundamental principle of toxicology is that the longer a substance is in the body, the more likely it is to be toxic.”
The issue of PFAS exposure is becoming increasingly driven by infrastructure considerations to treat water, control industrial processes upstream, and what is allowed in fertilizers and packaging materials rather than simply individual knowledge. Standards have been established for a number of PFAS in drinking water, but food and soil challenges continue to push the boundaries of monitoring and prevention. The one thing that comes through most clearly in the research is the persistence of PFAS: “Once PFAS are in water, soil, or the body, they don’t easily leave. This is what is driving the push to stop the flow of sources, to quantify what is already there, and to find a credible path to reduce the impact over time.”
