That is the exact question the U.S Food & Drug Administration (FDA) is asking. The agency has conducted 2 studies in the last 18 months to determine how the body absorbs chemicals from sunscreen application. The results were a cause for alarm.
As a baseline, the FDA is not concerned if ingredients found in the bloodstream at a level of less than 0.5 nanograms per milliliter. Results from one study found 6 sunscreen chemicals at levels of 3.3 to 258.1 nanograms per milliliter. That’s over 500 times the acceptable rate.
The FDA cautions that this doesn’t mean to stop using sunscreen. As of yet, there is no evidence that the high levels of absorption are harmful. With current information, the benefits of using sunscreen still outweigh the drawbacks.
“Given the recognized public health benefits of sunscreen use, the U.S. Food and Drug Administration (FDA) urges Americans to use sunscreens in conjunction with other sun-protective measures (such as protective clothing).”
The study results have led the FDA to propose an update to regulations on sunscreens. This update would require sunscreen manufacturers to do further testing to provide more data on how active ingredients are absorbed and the long-term effects of that absorption. These regulation changes have been delayed, though, due to the COVID-19 pandemic.