May 06, 2019
We all know that wearing sunscreen is very important — even if you aren’t in direct sunlight. Best sun protection practices involve having some sort of sun defense on at all times.
That said, it’s important to note that there are ingredients in commercially-available sunscreen that we might need to protect ourselves from, which creates a fairly difficult and confusing situation.
The U.S. Food and Drug Administration released findings on Monday from a small clinical trial examining the effects of the four most common active ingredients in sunscreen — avobenzone, oxybenzone, ecamsule and octocrylen — after they’ve been applied to human skin, Wired reports.
The findings, according to the report published in JAMA, were the first to prove that the chemicals from sunscreen do, in fact, make their way into the bloodstream — a finding that experts have been iffy on in the past.
The study tested 24 healthy adult volunteers – 12 men and 12 women – who were randomly assigned to one of four sunscreens and applied the lotion four times a day for four days according to the directions on the bottle, according to the study. For a total of seven days, researchers collected blood samples four times per day to test for the presence of the four chemicals. Three of the active ingredients continued to rise in blood levels with daily use and lingered in the body for at least 24 hours after the sunscreen was first applied.
NBC News reports:
In order for sunscreen companies to avoid safety testing of the chemicals in their products, no more than 0.5 ng/mL of the active ingredients can be absorbed into the body. When the researchers analyzed the amount of these chemicals in the blood samples, they found all at higher levels than that threshold. The biggest difference was for oxybenzone, which was found to exceed 20ng/mL on day seven of the study.
While it has been proven that these chemicals can make their way into the bloodstream, it has not been confirmed that they’re doing anything harmful while they’re in there.
"The systemic absorption of sunscreen ingredients supports the need for further studies to determine the clinical significance of these findings," the study authors wrote. "These results do not indicate that individuals should refrain from the use of sunscreen.
The American Academy of Dermatology published a response to the findings of this study to point out that sunscreens have been used for several decades without any reported internal side effects in humans.