Irradiation effects on canvas oil painting: Spectroscopic observations

“Winter” oil painting, by Romanian contemporary artist George Alexandrescu was used as experimental model for the substantiation of gamma radiation treatment, as the best choice to stop the biological attack of paintings. In this purpose, spectroscopic and colorimetric methods were used to analyse in situ, non-destructively and non-contact, the experimental model before and after 60Co gamma irradiation. Chemical structure and colour changes were monitored by FTIR, FT-Raman and Vis reflectance spectroscopy. Negligible Infrared spectral transformations have been observed after irradiation. Furthermore, it was found that gamma irradiation did not induce any significant colour alterations. Insignificant structural and colour changes observed, recommend the use of gamma irradiation in the disinfection of oil paintings.

► Oil painting experimental model was gamma irradiated at 33 kGy.
► Changes induced by gamma irradiation were investigated in situ by spectral methods.
► Insignificant FT-IR/Raman spectral and colour variations were observed.
► Negligible changes recommend the irradiation for oil paintings disinfection.