Matta MK, et al. - In this randomized clinical trial involving 24 healthy candidates, researchers ascertained if the active ingredients (avobenzone, oxybenzone, octocrylene, and ecamsule) of four commercially available sunscreens are absorbed into systemic circulation. They found that maximum plasma concentrations for the active ingredient avobenzone were 4.0 (60.9%), 3.4 (77.3%), 4.3 (46.1%), and 1.8 (32.1%) ng/mL, respectively, for two different sprays, a lotion, and a cream. The investigators also noted that the application of thse four sunscreens under maximum conditions of use resulted in plasma concentrations exceeding the FDA threshold for the possibility of waiving some non-clinical sunscreen toxicology studies. Rash was the most common adverse event, which developed with each sunscreen in one participant. These outcomes, however, did not suggest that people should refrain from using sunscreen. The sunscreen ingredient systemic absorption supports the need for further studies to determine the clinical significance of these findings.