Influence of Human Hair Medulla in Solar UV Transmission Through Skin

Abstract The role human hair plays on the solar ultraviolet (UV) transmission in the skin has been investigated regarding melanoma development in our previous work. However, due to the lack of knowledge about the optical properties of human hair medulla, hair has always been modelled as a homogenous structure in Monte Carlo (MC) simulations of photon transport in skin. In this paper, we have estimated the ratio range of the absorption to attenuation coefficient of hair medulla, in order to examine how the presence of medulla would affect the solar UV transmission in the skin. This was simulated in TracePro™ software with the implementation of the MC method for photon transport. The results show that medullated and non-medullated terminal hairs have similar shielding effects against solar UV transmission into skin.