Spectral emission variability in commercial led masks for cosmetic use.

Facial LED masks for aesthetic purposes are widely available online, allowing unrestricted application times without professional supervision. This study analyzed four masks with different LED colors to evaluate the information provided by the manufacturers and to measure their spectral irradiance. Documentation lacked data on emitted energy across wavelength ranges, its absorption by the skin, and potential health consequences of improper use. Measurements revealed pronounced variability in irradiance, with considerable differences in peak positions and spectral distribution for some LED colors, such as yellow or violet. In some cases, the total irradiances were higher than that from sunlight. Despite similar recommended session durations, the differences in irradiances result in markedly different physical doses. Current evidence regarding the biological effects of visible light absorption through the skin at different doses-and its medium- and long-term implications-remains limited. These findings highlight the need for regulatory measures to define energy limits for such masks and for consumer guidance on potential health risks associated with indiscriminate exposure to visible light.