Effects of Ultraviolet B Radiation on Physicochemical Properties of Human Hair Shaft

The study, involving hair samples from 20 females aged 25 to 31, examined the impact of UVB radiation on human hair shaft properties. UVB doses of 400, 2,000, and 4,000 mJ/cm² were used to irradiate the hair. The results showed that UVB exposure did not significantly change the hair's morphology or surface roughness. However, chemical alterations were observed, including a transformation in the keratin structure from alpha-helix to beta-sheet and the development of stretching modes in C-H lipid alkyl chains, as detected by FTIR spectroscopy. Additionally, an increase in UVB intensity led to a reduction in water content in the proximal root of the hair. Despite the lack of significant physical damage, UVB radiation did affect the hair's chemical composition and hydration.