Feasibility study of using gamma ray for fungal decontamination of historical oil painting

Abstract

In this study, gamma irradiation as a method for fungal decontamination of a historical oil painting was evaluated. For this purpose, an oil painting belonging to the Ghajar period with Ghahvekhanei style was selected. Sampling of suspected and discolored points on the surface and backside of the artwork was done and the total counts of fungi were detected. The dose of gamma ray for decontamination of painting was calculated. To study the radiation effects on the color materials used in the painting, small samples were taken from its two main colors. The chemical structure and color measurement of the samples were monitored by FTIR and colorimeter before and after the irradiation. No infrared spectral changes were observed after the irradiation. Furthermore, it was found that gamma irradiation did not induce any significant color alterations. These results showed that irradiation with tested dose (5 kGy) did not damage the oil painting and therefore the radiation method could be recommended for disinfection of this kind of artwork.

Keywords

• gamma ray
• oil painting
• fungal contamination
• calorimetric test