Exploring Skin Interactions with 5G Millimeter-Wave through Fluorescence Lifetime Imaging Microscopy

Abstract

The ongoing expansion of fifth-generation (5G) and future sixth-generation (6G) mobile communications is expected to result in widespread human exposure to millimeter-wave (mmWave) radiation globally. Given the short penetration depth of mmWaves and their high absorption by the skin, it is imperative to investigate the potential effects of 5G radiation not only in terms of temperature increase but also at the cellular level. To understand the biological mechanisms of mmWave effects, accurate methods for assessing mmWave absorption in the skin are crucial. In this study, we use fluorescence lifetime imaging microscopy (FLIM) to explore these effects. Employing a mmWave exposure system operating at 26 gigahertz (GHz), porcine skin is irradiated for varying durations (5, 10, 20, and 30 min). We investigate changes in tissue temperature and the autofluorescence of flavin adenine dinucleotide (FAD). Our findings suggest that operating our mmWave exposure systems at the configured power level of 26 GHz is unlikely to cause damage to FADs, even after a 30 min exposure duration.