Per- and poly-fluoroalkyl substances (PFAs) and perfluorooctane sulfonate (PFOs) are manufactured chemicals in various everyday products. Though PFOs are a type of PFA, they are both known as "forever chemicals" because the time it takes for them to break down in the environment is very, very long. PFAs can make their way into the human body through contaminated water sources and food, leeching through packaging and products like cookware and waterproof clothing.

When people have high levels of PFAs in their bodies, they are susceptible to kidney, breast, and testicular cancers. Plus, PFAs have been linked to immune and cardiovascular system damage, thyroid disease, higher cholesterol levels, low birth weight, developmental issues, endocrine disruption, and fertility issues.