Biodeterioration

The biodeterioration of organic and inorganic materials, as well as polymers, is a complex of alteration processes induced by the growing and metabolic activity of organisms. It can be recognized on monuments, wall paintings, stone, wood, paper, vegetal/animal fibers, and parchment artworks. As defined by Hueck, 1968, biodeterioration is “any undesirable change in the properties of a material caused by the vital activities of organisms”; this definition is accepted as the meaning of the phenomenon. Both macroorganisms (such as animals, plants, and mosses) and microorganisms (such as autotrophic or heterotrophic bacteria, microfungi, cyanobacteria, algae, and lichens) represent the triggers of biodeterioration for cultural heritage. Understanding the morphological and physiological features of the biodeteriogens is required to establish the kind of interaction that occurs with the material and to assess the cause-effect of the biodeterioration action of a specific identified biological agent. For a complete evaluation of biodeterioration, a proper sampling and identification of the majority of biodeteriogens are required. Therefore, in order to apply a prompt and effective conservation to limit further damage, evaluating and quantifying the presence of biological systems that induce damage in heritage materials is indispensable.