The effect of ethylene oxide and silver nanoparticles on photographic models in the context of disinfection of photo albums

The purpose of the study was to evaluate the efficacy of photographic models' disinfection with ethylene oxide (EtO) and silver nanoparticles (AgNPs). The models were made using POP (Printing Out Paper) methods: salted paper, albumin, collodion, gelatine on Whatman and Fabriano paper artificially infected with bacteria (Bacillus subtilis, Streptomyces sp.) and mould (Aspergillus versicolor, Trichoderma viride). Moreover, the study was supposed to determine the influence of disinfection, including the impact of artificial ageing, on the optical and mechanical properties and pH of the photos and volatile compounds residues after EtO disinfection. The studied microorganisms developed on all tested photographic models after seven days incubation. After disinfection, the microorganisms number reduction amounted to R = 28.27 – 99.01% for AgNPs and R = 100% for EtO. No significant changes were discovered in the pH or the breaking length after ageing and disinfection with AgNPs and EtO for most of the samples. The photographic models - albumin and gelatine after disinfection with EtO and artificial ageing - significantly changed their colour. EtO disinfection results in chemical degradation of the photograph matrix and 2-chloroethanol retention (GLC-MS). EtO was demonstrated to be a more effective photograph disinfection method than AgNPs. AgNPs, in turn, exerts a lower impact on the material properties of the photographic models than EtO.