Microbial deterioration of cultural heritage and works of art — tilting at windmills?

Abstract

Microorganisms (bacteria, archaea and fungi), in addition to lichens and insect pests, cause problems in the conservation of cultural heritage because of their biodeteriorative potential. This holds true for all types of historic artefacts, and even for art made of modern materials, in public buildings, museums and private art collections. The variety of biodeterioration phenomena observed on materials of cultural heritage is determined by several factors, such as the chemical composition and nature of the material itself, the climate and exposure of the object, in addition to the manner and frequency of surface cleaning and housekeeping in museums. This study offers a review of a variety of well-known biodeterioration phenomena observed on different materials, such as stone and building materials, objects exhibited in museums and libraries, as well as human remains and burial-related materials. The decontamination of infected artefacts, exhibition rooms and depots incurs high expenditure for museums. Nevertheless, the question has to be raised: whether the process of biodeterioration of cultural heritage can or should be stopped under all circumstances, or whether we have to accept it as a natural and an implicit consecution of its creation. This study also highlights critically the pros and cons of biocide treatments and gives some prominent examples of successful and unsuccessful conservation treatments. Furthermore, an outlook on the future research needs and developments in this highly interesting field is given.

Evaluation of a Parchment Document, the 13th Century Incorporation Charter for the City of Krakow, Poland, for Microbial Hazards

“…Such events took place, for instance, in Florence in 1966, Petersburg in 1988, Poland in 1997 (21), and Japan in 2011 (40). The isolated bacterial strains create the microflora that is typical of archival collections (15,35,36) and other historical and museum objects (29,41). The microbiological picture of the object in question was supplemented by bioluminescence analysis, which showed an average level of organic contamination on the surface of the document, compared with that of other historical objects analyzed in the author's own studies.…”

“…The main structural material, i.e., collagen, is degraded in later stages. The hydrolysis of collagen and other protein elements can also lead to changes within nonorganic components, resulting in stains and discolorations (41). In this study, the destructive potential of isolated microbes was determined by the verification of their proteolytic properties and their ability to grow on parchment.…”

“…It is essential to guarantee appropriate temperature and humidity in storerooms (41,48). According to the recommendations of the International Federation of Library Associations, the indoor temperature in archives should range from 18°C to 20°C, and the humidity should be 50% to 60%.…”

Fungi and Bacteria in Indoor Cultural Heritage Environments: Microbial-related Risks for Artworks and Human Health

“…So far, several researches have proved that molecular biology is extremely useful also in the field of conservation of cultural assets [18][19][20][21]. Interest in assessing microbial air contamination has particularly increased over the last years, in relation to the potentially harmful effects related to microbial systems that can be amplified by the presence of many other compounds [22][23][24][25][26][27].…”

Humusica 2, article 13: Para humus systems and forms

“…Rock crusts may evolve into Soil crusts once enough mineral soil material has accumulated, or dust material has been trapped, for example in rock pockets/bowls (Souza-Egipsy et al, 2004). Nos crusts, in literature also called cryptogamic covers, may appear even on non-rocky solid substrates, like bark (Elbert et al, 2012), building and historical monuments (Gadd, 2007), human manuscripts or paintings (Sterflinger and Pinar, 2013), plastics (Crispim et al, 2003), or even liquid substances (mud, oil, dirty water, Höpner et al, 1994). With the help of a knife it is possible to remove the thickest humipedons from the substrate like a carpet or a stiff aggregate crust (< 3 cm), corresponding to thick Nos crusts (example in Figure 2e) or Soil crusts (Fig.…”