A pilot study recently published in the medical journal, JAMA, found that it took just one day of sunscreen use for several active ingredients in sunscreen products to enter the blood stream at high levels. The sunscreen absorption study, which was conducted by a branch of the US FDA, examined four chemicals: avobenzone, oxybenzone, ecamsule, and octocrylene. These four chemicals are part of the twelve chemicals that the FDA is requesting more information on from manufacturers to be considered for GRASE (Generally Regarded As Safe and Effective) status. Three of the ingredients continued to be present in the bloodstream and rose in concentration as daily use continued. After stopping sunscreen applications, they remained in the body for longer than 24 hours.

Physical Sunscreens vs. Chemical Sunscreens:

According to the American Academy of Dermatology and the American Academy of Dermatology Association, physical sunscreens work like a shield while chemical sunscreens work like a sponge. Physical sunscreens contain the active(s) zinc oxide and/or titanium dioxide, and work by sitting on the skin’s surface deflecting the sun’s rays. On the other hand, most chemical sunscreens contain one or more of the following active ingredients that absorb the sun’s rays: oxybenzone, avobenzone, octisalate, octocrylene, homosalate, octinoxate.

Originally, the chemical sunscreens were used in small quantities for preventing sunburn on vacation. According to a CNN article, the FDA started to become concerned about chemical safety when sun protection agencies started recommending daily application on large parts of the body.

Oxybenzone seems to be the most concerning active ingredient in sunscreens. In a small FDA study of sunscreen chemicals, oxybenzone was absorbed into the body at a concentration of approximately 50 to 100 times higher than the other three chemicals. Other studies have shown a potential link between oxybenzone and changing hormone levels in men, including lower testosterone. According to the article, it is also the most common cause of contact allergies and can also leach into breast milk.

Experts say that you should NOT stop using sunscreens. Further studies need to be conducted to determine the medical implications, if any, of sunscreen absorption. However, the increasing awareness surrounding the potentially harmful absorption of these chemicals encourages consumers to be more cautious about the type of sunscreens they purchase. Alternative sun protection methods include avoiding sun exposure at peak times, using protective clothing, and wearing a hat.

For more information, please contact Focal Point Research Inc.  We are leading North American Regulatory and New Product Consultants for Medical DevicesNatural Health ProductsOTC DrugsCosmetics, and other consumer products regulated by Health Canada and the U.S. FDA.