Sunscreen Ingredients Are Absorbed in Blood
Over the past year, 2 small clinical trials have been done by a team at the FDA on sunscreen absorption in the blood. The first trial found that four active ingredients in sunscreen applied under “maximal use conditions” are absorbed into the blood at levels high enough to warrant further safety research. Sunscreen was applied every 2 hours (as the label recommends) 4 times a day, to represent a full day at the beach or pool. This was repeated for four days in a row, to represent what might occur during a vacation.
The second study set out to determine the absorption after a single application. It found that the absorption of all six of the active ingredients studied occurred on the first day after a single application. These active ingredients remained in the blood for extended time periods. Two were still detectible 21 days later.
The leader of the studies stressed that just because active ingredients in sunscreens are absorbed does not mean they are unsafe. Two of the active ingredients – zinc oxide and titanium dioxide – are generally recognized as safe by the FDA and additional data are not needed for them. The FDA is proposing requesting additional safety studies from the industry and other interested parties. They strongly advise all Americans to continue to use sunscreen in conjunction with other sun-protective measures.
Terry Pfau DO, HMD