Where is Cladosporium found?
Although Cladosporium species are abundant globally, they are dominant in temperate climates.14 For Cladosporium herbarum, the optimal temperature for growth is 18 to 28 C (roughly 64 to 82 F), but it can grow below 0 C (32 F) and can even live on frozen meat.9 Found mainly on plants, in soil, and on food, C. herbarum can also colonize a host of indoor surfaces such as window panes and insulation in heating and cooling systems.3,5 That's because mold reproduces via spores, which can be transported by air, water, and insects.10,15 So even if a fungus originates outdoors, it often can enter a dwelling through a variety of means, including doorways, windows, vents, and heating and air conditioning systems.16
While this mold can be clearly visible at times, at other times its undetectable by the naked eye. It can often be found in bathrooms and basements and on surfaces such as fabrics, wood, wallpaper, carpets, rugs, windowsills, grills, upholstered furniture, faucets, and curtains. Cladosporium is extremely widespread indoors, for according to some air-pollution studies, all tested homes in Canada contained Cladosporium spores, as did 70 percent of similarly tested U.S. homes.9