There are many strains of black mould that are not toxic. We have found that non-toxic black mould is the most prevalent. There are hundreds of microscopic forms of fungi that grow into visible colonies under the right conditions.  You can find a science project growing in any damp inaccessible area. They produce spores that very readily create and produce allergic reactions similar to common pollen or animal allergies. The reactions can be flu like symptoms such as cough, congestion, headache, and extreme eye irritation. The cause of nearly all chronic sinus infections is black mould and it has been linked to a 300% increase in asthma in the past 20 years.

Now the question is what to do about Mycotoxins, fungi, and mould, particularly black mould. In particular, this site is devoted to addressing the issue of black mould removal.