Most mold species that grow commonly in homes release irritants called mycotoxins. Mycotoxins released from black mold cause several health problems and symptoms, ranging from mild irritation and hay fever to potential nerve damage.
These pollutants can be fatal to small children and elderly people with some sensitivity to mold. Other hazardous mold species, such as fusarium, aspergillus, Cladosporium, and Penicillium, cause discomfort and illnesses but not fatal.