PFAS are common industrial and industrial compounds, and often found in things like no-stick frying pans. Past research has connected PFAS to things like lower birth weight, weakened immunity, and certain cancers. Here we will note that many of the studies were done on populations with higher degrees of exposure to the ingredients; while more research is needed to make definitive claims, many people—ourselves included—avoid them altogether out of caution.
Additionally, they are actually what’s known as “forever chemicals,” meaning they don’t break down. Both scientists and environmental activists see the concern in this as it means it can bioaccumulate in your body and the earth, like our water supply as an example. As Graham Peaslee, Ph.D. a physics professor at Notre Dame and the principal investigator of the study, said in this Associated Press article: “PFAS is a persistent chemical. When it gets into the bloodstream, it stays there and accumulates.”
Now, this study was only about the presence of PFAS in cosmetics—it did not look at outcomes, side effects, or the like. So we cannot draw health-related conclusions at this time, but Peaslee did describe his findings (especially the products with higher concentrations) as, “worrisome,” according to the AP article.