The aim of this study was to select effective and safe microbiocides for the disinfection and protection of historical wooden surfaces at the former Auschwitz II-Birkenau concentration and extermination camp. We tested seven active compounds against bacteria and moulds, of which didecyldimethylammonium chloride and N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine were effective even at 0.02%-2%. Subsequently, eight microbiocides containing the selected active ingredients were chosen and applied three times on the surface of wood samples colonized by bacteria and moulds. ABM-1 and ABM-2-6% solution; Rocima 101-8%; Preventol R 80-12%; Acticide 706 LV-15% and Boramon-30% were the most effective disinfectants. Under laboratory conditions, ABM-1, Boramon and Rocima 101 ensured antimicrobial protection of new wood samples for six months. In situ, 30% Boramon and 8% Rocima 101 applied by spraying effectively protected the historical wood from bacterial and mould growth for 12 and 3 months, respectively. Colour and luminance of the new wood were not altered after exposure to the biocides. Boramon and Rocima 101, applied by the spraying method, caused no significant change in the colour of the historical wood. Results from this study were used to develop a procedure for the protection of wood in historical buildings against biodeterioration.
Keywords: disinfection; historical wood protection; microbiocides; quaternary ammonium compounds.