It takes just one day for a number of common ingredients found in sunscreen to enter a person’s bloodstream, according to research from the U.S. Food and Drug Administration.
The study, published in The Journal of the American Medical Association (JAMA) on May 6, examined how several chemicals found in four commercially available sunscreens were absorbed into the bloodstream of 24 healthy participants.
Between July and August 2018, scientists studied four chemicals commonly found in sunscreen: vobenzone, oxybenzone, ecamsule and octocrylene.
Participants applied one of either a lotion-sunscreen, cream-sunscreen or two sprays, four times a day for four days on areas of the body uncovered by their swimwear. 30 blood samples were collected from each participant over a period of seven days.
Upon analyzing plasma levels in the participants’ blood samples, scientists found that the level of active ingredients in their bloodstreams was high enough to spark a government investigation.
The four chemicals were discovered to have entered the bloodstream at levels that exceed the FDA’s recommended threshold without a government safety inspection.
Additionally, three of the chemicals accumulated in the bloodstream with continued daily use, and remained in the body for at least 24 hours after the sunscreen had been applied, CNN reported.
Almost all participants had levels of the chemicals which exceeded 0.5 ng/ml within one day—the “Threshold of Toxocological Concern” (TTC). The TTC was developed by the FDA as a measure for a chemical to “undergo nonclinical toxicology assessment” to examine its effects on the body, reported The New York Daily News.
The chemical oxybenzone stood out among the four chemicals as the one that was absorbed into the bloodstream at the highest rate. It was discovered at levels as high as 209.6 ng/mL.
David Andrews, senior scientist at The Environmental Working Group said: ”Looking through the results tables of the study, one thing about oxybenzone stood out.
”Oxybenzone was absorbed into the body at about 50 to 100 times higher concentration than any of these other three chemicals they tested.”
Despite the findings, experts urge people to continue using sunscreen. The study emphasized that the research does not “indicate that individuals should refrain from the use of sunscreen.”