What is “Teflon flu”? It is linked to the coating of certain non-stick pans.

Last year, 267 suspected cases of the little-known disease were reported, one of the highest numbers since 2000, according to America’s Poison Centers, a nonprofit organization that oversees 55 U.S. poison control centers.

Teflon and many other nonstick pans are made from polytetrafluoroethylene (PTFE), which belongs to the larger class of substances known as PFAS (per- and polyfluoroalkyl substances) — or “forever chemicals,” because of their ability to persist in the environment for years.

Studies have shown that PTFE nonstick pans are safe for cooking when used as directed. But at very high temperatures (when a nonstick pan is exposed to temperatures above 500 degrees Fahrenheit), the coating can begin to break down and burn off potentially harmful fumes.

Julie Weber, director of the Missouri Poison Control Center, said questions about using nonstick pans are more common than reports of polymer clay fever. Weber said it’s important to use the pans as directed. “A lot of it depends on a person not taking shortcuts, following instructions and using things correctly,” she said.

So how do you use nonstick pans? The Washington Post spoke to several experts about polymer fume fever and nonstick pan coatings. Here’s what they said.