Sunscreen companies have long claimed the harmful chemicals in their products aren’t absorbed into the body. Turns out they are.
Sunscreens contain more chemicals at higher concentrations than they did 50 years ago. They are also applied much more frequently these days.
These two facts have prompted the FDA to re-evaluate the safety of sunscreen.
First the agency conducted a study to determine whether the chemicals used as active ingredients in the products are absorbed into the bloodstream, which, though it seems obvious, the industry has denied.
“Because sunscreens are formulated to work on the surface of the skin, some have argued that sunscreens would not be absorbed in appreciable quantities and therefore that studies are unnecessary,” the agency said in a press release.
The first study, published in 2019 in the Journal of the American Medical Association, found the opposite to be true: The chemicals are absorbed into the bloodstream at concerning levels.
The 24 participants in the study were instructed to apply sunscreen four times per day for four days on all areas that wouldn’t be covered by a swimsuit, an amount one might realistically apply on a beach vacation.
Researchers then measured the concentration of four different active ingredients in their blood: avobenzone, oxybenzone, octocrylene and ecamsule.
After just one day, all four chemicals were found at levels that far exceed the amount at which the FDA requires safety testing (anything higher than .5 nanograms per milliliter).
For oxybenzone, which has been found along with other sunscreen ingredients in breast milk, blood concentrations reached the threshold after a single application and exceeded 20 nanograms per milliliter on day 7 of the study.
Three of the chemicals remained in the bloodstream weeks later.
Since then, the FDA has conducted further studies on 14 common active ingredients found in most sunscreens and concluded in 2021 that only two of them could be classified as “generally recognized as safe and effective” — zinc oxide and titanium dioxide — (although I would bet letting heavy-metal nanoparticles absorb into your skin is not safe).
Many of the other twelve other common active ingredients — avobenzone, cinoxate, dioxybenzone, ensulizole, homosalate, meradimate, octinoxate, octisalate, octocrylene, oxybenzone, padimate O, and sulisobenzone — are known endocrine (hormone) disruptors.
Studies have linked oxybenzone with lower total testosterone levels in adolescent boys and cancer in rats, for example.
Octocrylene is often contaminated with benzophenone, a known carcinogen. According to one study, benzophenones levels can increase in products over time.
Several of the chemicals are also destructive to coral reefs, leading Hawaii to ban sunscreens that contain them.
“Creation of sunscreen products with SPFs greater than 15 and greater broad-spectrum protection against UVA and UVB rays have led to currently marketed products with more active ingredients combined together in higher concentrations than were previously used,” the agency noted.
Here are some natural alternatives: