After two hours, sunscreen that includes zinc oxide loses effectiveness, becomes toxic: study
— Read on phys.org/news/2021-10-hours-sunscreen-zinc-oxide-effectiveness.html
This research has shown a potential hazard to health exists by the use of sunscreens containing various metallic oxides. This has profound implications to the sunscreen industry and to people’s continuing use of sunscreens generally. NIH use approvals have to be updated. Meanwhile perhaps much slower natural exposure to sunlight is the best protection. It begs the question: Why don’t long-time nudists have higher skin cancer rates than non-nudists?