If you use sunscreen according to the manufacturer's recommendations, the active ingredients can already be detected in the blood after one day. It is not known if this represents a health risk.
To that promised on his bag UV protection sunscreens, gels and sprays contain various sunscreen substances. Researchers at the US Food and Drug Administration have now investigated whether and in what quantity pharmaceuticals get into the blood after the application.1 For this they distributed 24 healthy subjects to four groups. For four days, participants used one of two sprays, a cream or a gel four times a day. For each, they wore about 2 mg per cm2 about 75% of the total body area to achieve the recommended application regimen, e.g. during a vacation at the beach, to simulate.
Serum samples contained more than 200 ng / ml of oxybenzone
All tested products are available for free in the US and contain at least one of the following UV filters: avobenzone, oxybenzone, octocrylene and ecamsul. From the first day of use, the Photoprotective substances in the blood – in each case, at concentrations> 0.5 ng / ml. This value marks the threshold from which the Food and Drug Administration requires toxicological investigations. In the following days, the numbers continued to increase. The serum concentrations of oxybenzone were the highest: in one of the solar sprays, they were> 200 ng / ml.
The waiver would probably be more harmful
The results throw a little explosive questions on, write Dr. Robert M. Califf from the Duke University School of Medicine in Durham and dr. Kanade Shinkai of the University of California at San Francisco in his accompanying editorial:2
- Does systemic absorption of substances pose a health risk?
- How do factors such as skin type or sun exposure affect absorption?
- Is there higher absorption in children because of the different ratio of body volume to surface?
Until these issues are resolved, the authors emphasize that the current recommendations should be maintained and disseminated. Because we Waiver to the sunscreen of the news could be essential more harmful consequences for health. The authors recommend more and more recommending formulations containing mineral absorbers (reflective) such as titanium dioxide and zinc oxide as part of a broader program of protection solar, which includes avoiding the sun and wearing protective clothing.
1. Matta MK et al. JAMA 2019; first online
2. Califf RM, Shinkai K.A.A.O.