What are forever chemicals?

Chemists are currently at loggerheads about the definition of per- and polyfluoroalkyl substances (PFAS), also known as forever chemicals. PFAS are incredibly useful: they’re found in many objects we use everyday, such as non-stick pans and water-resistant clothing, and in firefighting foams. However, they can be hugely harmful to both the environment and human health. Discover what makes PFAS so useful, why they are risky and how scientists are combating PFAS pollution.