In Elemental. More on Medium.
For a 2019 study, researchers at the U.S. Food and Drug Administration had healthy people apply common, commercially available sunscreens.
For four days — and four times each day — the people in the study sprayed or rubbed sunscreen onto their bodies. Most sunscreen labels advise people to reapply “at least every two hours,” so the study was designed to assess what would happen inside the body if people followed this guidance. For example, if someone went on a beach vacation and slathered on sunscreen throughout the day, as directed, what, if anything, might show up in their blood?
To…