What a good point.
I worked in a shop and in the store room there was a funny noise coming from the ceiling, like squeeking, anyway this was going on for ages and the place really was damp and moldy and i was beginning to feel really weird, i had all sorts of symptoms, chest pains, fatigue, palpitations, etc.
One day i was so ill, i told my boss i couldnt go in and i was off sick for 6mths.
I went in the shop a few months later to get my wages and i went to the store room and there was a big hole in the ceiling, my boss said that a piece of mould came fthrough the ceiling and it was about 3 foot square, how gross!
No wonder i was ill.
Last year i got ill when i opened our car that had been off the road for months and there was mould and mushrooms growing on the carpet where it was damp, from that moment i was so ill.