Aspergillus is a group of fungi that occurs both outside and indoors and has been known to grow on cannabis.

Aspergillus mould can grow on improperly stored cannabis. Healthy people can tolerate inhalation of spores, but it can cause serious harm to both humans and animals who have compromised immune systems. Spore overload can cause serious infection in the lung (Aspergillosis), which can spread rapidly to other parts of the body and be fatal.

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