Perfluoroalkyl substances (PFAS) are harmful chemicals found in nonstick pans, cosmetics, and more. Now, a new study shows they’re in dental floss as well. In the study, researchers found that women who flossed with products that contain fluorine (a marker of PFAS) had higher levels of the chemicals in their blood than those who used other types. The results would likely hold for men as well.
The findings prove that PFAS migrate out of household products and into people’s bodies, says lead study author Katie Boronow, a staff scientist at the Silent Spring Institute in Newton, Massachusetts. Exposure has been linked to increased risk of cancer, reduced fertility, and lower immune responses to vaccines. If you use floss characterized as “easy glide,” chances are it contains these chemicals. A specific type of PFAS called Teflon, which gives products nonstick properties, may help the floss move smoothly between your teeth, Boronow says.
You’re likely exposed to PFAS at several points throughout the day like when you’re cooking, so it’s important to limit them when you can. Burden suggests you avoid any floss with descriptors like Teflon or PTFE (the scientific word for Teflon). Listerine Cool Mint fits the bill.