All six tested sunscreen active ingredients were systemically absorbed above the FDA threshold, reinforcing the need for further safety data

This follow-up to the landmark 2019 FDA study expanded the investigation to six sunscreen active ingredients (avobenzone, oxybenzone, octocrylene, homosalate, octisalate, and octinoxate) across four formulations (lotion, aerosol spray, non-aerosol spray, and pump spray). All six ingredients exceeded the FDA's 0.5 ng/mL plasma concentration threshold after a single application, and concentrations increased with repeated application over the 21-day study period. The authors again emphasized that systemic absorption does not equal harm but that additional safety studies are warranted.

U.S. Food and Drug Administration