Reducing biocide use in building conservation
A large number of historically and culturally important stone structures (e.g. buildings, archaeological sites, etc.) exist across Europe. Unfortunately, this great heritage is threatened by films of microorganisms that accumulate on the surface of these structures, often causing irreparable damage. Currently, biocides are used to destroy the biofilms, but they are unattractive from an environmental point of view and may otherwise harm the objects they are intended to protect. Geomicrobiologists with the University of Oldenburg led an investigation of alternative methods of biofilm removal and prevention. They teamed up with six other organisations in the framework of the BIODAM project. What they discovered is that the concentration of biocides can be drastically reduced by combining them with other chemical compounds. The mixture they formulated includes polysaccharide inhibitors to block slime development and photosensitizers that are activated by incident solar radiation. Pigment inhibitors and cell permeabilizers complete the picture. Feedback from trials carried out during BIODAM is being analysed and more trials are planned in the near future. Conservationists, museum curators and other interested parties may come into contact with the University of Oldenburg and/or its BIODAM partners to learn more about these developments.