January 22, 2020
Though sunscreen is beneficial for protection against the harmful rays of the sun, a new study reveals that several ingredients can enter the bloodstream at potentially unsafe levels.
Six chemicals commonly found in sunscreen products are absorbed into the bloodstream and remain there for days afterward, according to a study conducted by the U.S. Food and Drug Administration.
Still, FDA officials urged consumers to continue wearing sunscreen.
"The fact that an ingredient is absorbed through the skin and into the body does not mean that the ingredient is unsafe, nor does the FDA seeking further information indicate such," Dr. Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, said in a statement.
"Rather, this finding calls for further industry testing to determine the safety and effect of systemic exposure of sunscreen ingredients, especially with chronic use."
The chemicals – avobenzone, oxybenzone, octocrylene, homosalate, octisalate and octinoxate – remained at unsafe levels three days after the sunscreen product was last applied, the study found. Homosalate and oxybenzone remained above safety levels 17 days later.
The study examined four different sunscreen formulations – lotion, aerosol spray, non aerosol spray and pump spray. Researchers randomly assigned 48 participants into four groups, with each group using a different sunscreen form.
On the first day of the study, participants applied the sunscreen once to 75% of their bodies. On the second, third and fourth days, participants were asked to apply sunscreen four times each day. Blood cultures were taken each morning prior to a required shower.
Not only did the chemicals absorb into the bloodstream, but their levels increased after subsequent sunscreen applications, the study found.
The FDA emphasized that more research is needed to understand whether the chemicals can be labeled as generally regarded as safe and effective.