January 2025

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Health Capsule

What Are PFAS?

Chemicals called PFAS are sometimes in the news. PFAS stands for perfluoroalkyl and polyfluoroalkyl substances. PFAS are widely used and long-lasting. They’re found in everyday items like carpets, clothes, and cookware. They have many uses. For example, they can help keep food from sticking to packages and prevent stains on fabrics. PFAS are even used in some fire-fighting foams.

These chemicals do not break down easily in the environment. And they can build up in the blood over time. Some studies have found that PFAS can be detected in the blood and urine of people and animals.

Scientists are working to better understand how PFAS might affect human health. Some studies have found links between PFAS and increased risk for some cancers. Others have found that PFAS are linked to changes in metabolism or body weight.

In the early 2000s, some PFAS chemicals were removed from consumer products. One study found that blood levels of the chemicals dropped after that. But since then, new PFAS chemicals have been created. NIH-supported studies are continuing to assess the potential health effects of these new products. But because there are thousands of variations in PFAS chemicals, they can be hard to study.

Learn more about PFAS.