Table 2. Important sources of frequently occurring mold species and genera (examples from practical investigations).

Species or genus	Important sources
Cladosporium herbarum, Alternaria alternata, Botrytis cinerea	Vegetation, outdoor air-associated
Aspergillus versicolor complex and Scopulariopsis brevicaulis	Damp plaster
Xerophilic Aspergillus species of the Restrictus complex (esp. A. penicillioides and A. restrictus) as well as Aspergillus glaucus/pseudoglaucus and A. montevidensis, Wallemia sebi	Cellulose-containing materials with only slightly increased moisture
Aspergillus fumigatus	Composting, rotting of plant material, indicator for thermotolerant processes
Chaetomium spp., Trichoderma spp., Phialophora spp.	Colonizer of damp wood and cellulose materials such as cardboard
Penicillium species	Perishable food, waste, organic waste and wallpaper, house dust
Sarocladium strictum, Parengyodontium album, Lecanicillium psalliotae and Simplicillium spp.	Polystyrene floor insulation with prolonged moisture penetration
Stachybotrys chartarum, Acremonium spp, Chaetomium spp.	Very moist, cellulose-containing building materials
Wallemia sebi, Aspergillus restrictus complex	Keeping caged animals with bedding