Application of γ rays in insecticidal sterilization of document archives

In this study, the optimal dose of irradiation for insecticidal sterilization was investigated by simulating different doses of γ rays irradiation on paper samples (simulated paper document archives), and the mechanical properties of paper, colors of patterns and handwriting were analyzed. In case of Aspergillus, Bacillus subtilis, tobacco beetle, and ctenolepisma villosa, the killing rate > 99.9% was achieved when the absorbed dose was 2 kGy. After aging, the mechanical properties, gutters and ink marks of the samples were kept at least 80% of the original ones, which would not affect the later preservation. In consideration of the effectiveness of insecticidal sterilization, safety of paper document archives, and economics of irradiation services, the absorbed dose of 2 kGy was appropriate for the preservation of document archives. (authors)