Microbial environmental monitoring in museums: Preventive conservation of graphic collections

In museums, the biological component of indoor air, called bioaerosol or biological aerosol, is a potential biodeteriogen for graphic collections. The biological particles settling on the surface of artworks find favorable nutritional and environmental conditions for their growth, and promote biodeterioration. As is well known, biological attacks depend on microclimatic conditions; for this reason their control is essential to assess contamination and estimate biological risks. This article presents the partial application of a methodological model, in the National Institute of Graphic Arts (Istituto Nazionale per la Grafica-ING), a museum of international importance in Rome, on a collection of ancient drawings in the Fondo Corsini, preserved in repository no.1. This model is based on an integrated system of biological environmental monitoring (air and surfaces) in association with microclimatic monitoring (repository no.1, cabinet no.6, volumes, drawings and outdoor) carried out in an interdisciplinary research project. The values of thermohygrometric parameters were stable enough during the monitored month and had no daily fluctuations. The qualitative and quantitative analysis of air contamination and that on the surfaces of drawings did not show a critical situation. This article describes a pilot study which has focused attention on the biological contamination of the graphic collections and is a contribution to standardizing a system of diagnosis-intervention for preventive conservation of organic cultural heritage preserved in museums and in other indoor environments and the protection of the health of operators and visitors.