Ecology, Detection and Identification Problems of Moulds in Indoor Environments

Robert A. SAMSON Ph.D.

Centraalbureau voor Schimmelcultures, The Netherlands, e-mail:

For many people working in the building industry or those who are consulting for indoor problems, identification of moulds does not seem a problem. In their opinion mould applying disinfectants or antifungal paints can easily solve problems. Furthermore, it is often recommended to modify the construction and adding ventilation with the result that the conditions for fungal growth can be reduced. However, if we like to know the cause and the degree of biodeterioration, in particular when health implications are involved, it is important to know which organisms are causing the problem. This is particularly true for species of Stachybotrys, Penicillium, Aspergillus and Fusarium.

Identification of mould isolates or specimens is problematic for the inexperienced researcher. This is partly due to the fact that the methods for identification are still based on the phenotypical characters of the moulds, which requires many skills in microscopical observations. In addition the mould flora of indoor environments consists of some problematic genera such as Penicillium, Aspergillus and Fusarium of which there is no general taxonomic consensus. Even experienced mycologists might reach different conclusions hence different names for an isolate.

Several surveys of moulds in indoor environments have revealed that we are dealing with a known and relatively low number of species. To detect these relevant species it is, however, essential to apply the appropriate methods. This paper is focused on the ecology and taxonomic problems of indoor moulds also related to methods of detection.