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How Can PFAS Affect Your Health?

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PFAS (per- and polyfluoroalkyl substances) are among the most ubiquitous synthetic chemicals in the world. Approximately 98 percent of Americans have PFAS in their bodies. People can be exposed to these chemicals in many different ways—through the water they drink, the products they use, the air they breathe, and the food they eat. During pregnancy, PFAS can pass from the mother to the fetus through the umbilical cord, and babies can be exposed through breast milk or formula made with contaminated water.

Although the science on health effects is still evolving, scientists are increasingly concerned about low-dose exposures, as they continue to find health effects at lower and lower levels. More research is needed on other PFAS chemicals, in particular ones that companies have developed to replace PFOA and PFOS. Because people are exposed to multiple PFAS from multiple sources, researchers are beginning to investigate the effects of mixtures of PFAS on human health.

girl and mother cooking

Their strong chemical bonds and unique structures make them very effective at repelling water and oil even at high temperatures. These same characteristics also make PFAS extremely persistent, meaning they don’t break down in the environment. Even more concerning, some PFAS can remain in the body for years, and people continue to be exposed to the chemicals.

Because of their persistence and because exposures are so widespread, scientists are concerned about the potential health impacts. Most health studies have looked at PFOA and PFOS, the two most commonly found PFAS. However, new research suggests other types of PFAS have similar health effects.

Scientific studies have linked exposure to PFAS with:

Human studies

  • High cholesterol
  • Ulcerative colitis
  • Cancer (testicular, kidney)
  • Preeclampsia
  • Liver damage
  • Thyroid disease
  • Decreased vaccine response
  • Asthma
  • Decreased fertility
  • Lower birth weight


Animal studies

  • Cancer (testicular, liver, pancreatic)
  • Liver damage
  • Delayed mammary gland development
  • Developmental problems
  • Effects on brain development
  • Immune system effects
  • Changes in cholesterol levels
  • Changes in thyroid hormones
  • Low birth weight