PFAS, or perfluoroalkyls and polyfluoroalkyl substances, are manmade chemicals found in a wide range of everyday consumer products such as nonstick cookware, upholstery, textiles, and even paper products meant to hold hot, greasy, or gooey food. They have been linked to high blood pressure, liver damage, cancer, low birthweight, and other adverse health effects. Microwave popcorn bags are one of the paper products that use PFAS to keep food from sticking, and studies have found that people who consume microwave popcorn regularly have markedly higher levels of PFAS in their bodies. It is recommended to limit daily use of microwave popcorn and switch to other evening snacks.
https://www.uclahealth.org/news/eating-microwave-popcorn-increases-the-level-of-pfas-in-body