The effect of 6 0 Co irradiation (1-250 Gy) on the optical properties of selected phosphate and silicate-based scintillating glasses was investigated by transmission measurements performed at room temperature in the UV-Visible part of the spectra. Samples doped with rare-earth ions (Ce 3 + , Tb 3 + as emission centres, and Gd 3 + as an additional constituent in certain compositions) have been studied. The results are discussed taking into account the possible influence of different glass compositions on radiation induced colour centres.