Mushroom poisoning, also known as
mycetism, refers to deleterious effects from ingestion of
toxic substances present in a
mushroom. These symptoms can vary from slight
gastrointestinal discomfort to
death. The
toxins present are
secondary metabolites produced in specific
biochemical pathways in the
fungal cells. Mushroom poisoning is usually the result of ingestion of wild mushrooms after misidentification of a toxic mushroom as an edible species. The most common reason for this misidentification is close resemblance in terms of colour and general
morphology of the toxic mushrooms species with edible species. Even very experienced wild mushroom gatherers are sometimes poisoned by eating toxic species, despite being well aware of the risks.
To prevent mushroom poisoning, mushroom gatherers need to be very intimately familiar with the mushrooms they intend to collect, including knowledge of the toxic species that look similar to these edible species. Other considerations regard methods of preparation and toxicity of some fungal species that appears to vary with geographic location, raising the potential of mushroom poisoning due to local toxicity of a correctly identified species.
There are many folk traditions concerning the defining features of poisonous mushrooms[1][2]. Unfortunately there are no general identifiers for poisonous mushrooms, and so such traditions are unreliable guides. For example, while some highly coloured mushrooms such as fly agaric are indeed poisonous, other strongly coloured mushrooms are harmless. Other highly toxic mushrooms, such as the appropriately named destroying angel, are of unremarkable white colour. Lack of snail or insect infestation is also an unreliable identifier, since fungi that are harmless to invertebrates can still be toxic to humans; the death cap, for instance, is often infested by insect larvae. Likewise, poisonous mushrooms neither blacken silverware during cooking, nor necessarily smell or taste unpleasant. Importantly, many fungal toxins are not particularly sensitive to heat and so are not broken down during cooking.
Persons who gather wild mushrooms should follow some practical guidelines (see mushroom hunting). In particular, they should not eat any mushroom they cannot positively identify; not allow small children to gather mushrooms for consumption; or mix known edibles with questionable species while gathering, since mushroom parts could break off and be confused with edible species.
