[Biological pollution of indoor air]

Biological pollution of indoor air can consist of viruses, bacteria, fungi, fungal spores, mites, dander and metabolic products from the microorganisms. The occurrence of such pollution can occasionally cause building-related adverse health effects. Allergens produced by house dust mites and in the dander of furred domestic animals are generally regarded to be among the most important causes of disease episodes in atopic individuals. Bacteria and fungi as such cause building-related disease more rarely. An exception is respiratory infections caused by Legionella bacteria. Other possible health effects of biological indoor air pollution have been suggested, but the data are inconclusive.