Absorption spectra of bone.

Absorption spectra of human bone and its two major constituents (collagen and apatite) were obtained in the wavelength region extending from 2000 to 12,000 A. In the last two cases a minimum transmission (maximum absorption) was uniformly observed in the ultraviolet region. The two samples after exposure to ultraviolet radiations show a shift in the peak positions. Absorption peaks in the total bone spectra are not reproducible in its two constituents. After exposure to UV radiations the position of maximum absorption is displaced. A possible interpretation of the observed results is presented.