In the 20th century, scientists developed a group of complex, manmade chemicals called per- and polyfluoroalkyl substances (PFAS). In the past decade, researchers have found these chemicals contaminating drinking water and the environment. Current research measures them at alarming rates in breast milk.
The properties of these substances include oil and water repellency, temperature resistance, and friction reduction. Experts estimate there may be up to 10,000 of these forever chemicals, the full effects of which aren’t yet known.
