Certain fungi, such as mushrooms, can produce poisonous toxins that may prove fatal if ingested (e.g. Amanita phalloides "death cap") Others (e.g. Psilocybe) affect the central nervous system inducing hallucinogenic responses.
Outbreaks of disease caused by chemical substances are rare, apart from intoxication caused by consuming poisonous fungi. In some CCEE and NIS with a tradition of collecting and consuming wild mushrooms, the death toll from mushroom poisoning reaches hundreds of people each year.