Disinfection of fungus using X-ray irradiation for the preservation of contaminated organic artifacts of traditional heritage

In disaster situations such as tsunamis, floods, and typhoons, fungal contamination can significantly intensify within 48 h of submersion, rapidly spreading and damaging the value and structural integrity of organic cultural heritage artifacts. Consequently, the application of radiation-based disinfection has been increasingly studied as an effective method for prompt and reliable treatment. In most cases, the fungal species were successfully eradicated at a radiation dose of 5 kGy (gamma rays). Nevertheless, certain fungal strains demonstrated high resistance and survived even at doses ranging from 10 to 15 kGy, making disinfection more challenging. Notably, differences in threshold disinfection doses between gamma rays and electron beams (E-beams) have been reported. Therefore, this study investigated the threshold dose of X-ray radiation required to disinfect representative fungi that damage organic cultural heritage artifacts, including Epicoccum nigrum (high radiation resistance), Cladosporium cladosporioides (moderate resistance), and Aspergillus niger (common resistance). E. nigrum was effectively controlled at a dose of 12.5 kGy, while C. cladosporioides was controlled at 7.5 kGy and A. niger was controlled within the 5 kGy range. The results of this study suggest that at least 12.5 kGy of X-ray radiation should be used to preserve waterlogged traditional Korean art pieces after flooding or other water disasters.