Non‐invasive diffuse reflectance measurements of cutaneous melanin content can predict human sensitivity to ultraviolet radiation

The diversity of human skin phenotypes and the ubiquitous exposure to ultraviolet radiation ( UVR ) underscore the need for a non‐invasive tool to predict an individual's UVR sensitivity. We analysed correlations between UVR sensitivity, melanin content, diffuse reflectance spectroscopy ( DR ) and UVR ‐induced DNA damage in the skin of subjects from three racial/ethnic groups: A sian, B lack or A frican A merican and W hite. UVR sensitivity was determined by evaluating each subject's response to one minimal erythemal dose ( MED ) of UVR one day after the exposure. Melanin content was measured using DR and by densitometric analysis of F ontana‐ M asson staining ( FM ) in skin biopsies taken from unexposed areas. An individual's UVR sensitivity based on MED was highly correlated with melanin content measured by DR and by FM . Therefore, a predictive model for the non‐invasive determination of UVR sensitivity using DR was developed. The MED precision was further improved when we took race/ethnicity into consideration. The use of DR serves as a tool for predicting UVR sensitivity in humans that should be invaluable for determining appropriate UVR doses for therapeutic, diagnostic and/or cosmetic devices.