If you've been seeing sun block with Mexoryl around, it's the latest greatest thing in sun blocks. It's been used in Europe and Canada for years and it's just became available in the U.S. It does a better job of blocking those nasty UVA rays that cause all those wrinkles and it's not as sticky feeling as the sun blocks you're used to. The usual sun blocks use avobenzone and zinc oxide. There has been some question lately whether sun screens can be dangerous since we absorb the chemicals they are made from through our skin. The latest consensus is that we probably don't absorb enough to be harmful and that going unprotected is too dangerous.