Also, here’s some extra info about “chemical” sunscreens from Badger Balm, who has a very in-depth post about the science of sunscreen and light dynamics (seen here and here):
Sunscreens such as avobenzone and oxybenzone have a very limited range of light wavelengths that they work on, meaning you need to use a larger assemblage of similar sun screeners in order to achieve a broad-spectrum sunscreen. Also, SPF only refers to the amount of UV-B rays that are blocked, and UV-A rays are the cancer-causing ones. So Broad Spectrum (or UVA-PF PA ++ grade or higher) is necessary!
