Mushroom Poisoning - Folk Traditions

Folk Traditions

There are many folk traditions concerning the defining features of poisonous mushrooms. Unfortunately there are no general identifiers for poisonous mushrooms, and so such traditions are unreliable guides. Use of folk traditions to try to identify edible mushrooms is a frequent cause of mushroom poisoning.
Examples of erroneous folklore "rules" include:

• "Poisonous mushrooms are brightly colored." – While the fly agaric, usually bright red to orange and/or yellow, is narcotic and hallucinogenic, there have been no reported human deaths; the deadly destroying angel, in contrast, is an unremarkable white, and the deadly Galerinas are brown. Some choice edible species (chanterelles, Amanita caesarea, Laetiporus sulphureus, etc.) are brightly colored, while most poisonous species are brown or white.
• "Insects/animals will avoid toxic mushrooms." – Fungi that are harmless to invertebrates can still be toxic to humans; the death cap, for instance, is often infested by insect larvae.
• "Poisonous mushrooms blacken silver." – None of the known mushroom toxins have a reaction with silver.
• "Poisonous mushrooms taste bad." – People who have eaten the deadly Amanitas reported that the mushrooms tasted quite good.
• "All mushrooms are safe if cooked/parboiled/dried/pickled/etc." – While it is true that some otherwise inedible species can be rendered safe by special preparation, many toxic species cannot be made toxin-free. Many fungal toxins are not particularly sensitive to heat and so are not broken down during cooking; particularly α-amanitin, the poison produced by the death cap (Amanita phalloides) and others of the genus, is not denatured by heat.
• "Poisonous mushrooms will turn rice red when boiled". – A number of Laotian refugees were hospitalized after eating mushrooms (probably toxic Russula species) deemed safe by this folklore rule and this misconception cost at least one person her life.
• "Poisonous mushrooms have a pointed cap. Edible ones have a flat, rounded cap." – The shape of the mushroom cap does not correlate with presence or absence of mushroom toxins, so this is not a reliable method to distinguish between edible and poisonous species. Death cap, for instance, has a rounded cap when mature.
• "Boletes are generally safe to eat" – It is true that unlike a number of Amanita species in particular, in most parts of the world, there are no known deadly varieties of the Boletus genus, which reduces the risks associated with misidentification. However, mushrooms like the Devil's Bolete are poisonous both raw and cooked and can lead to strong gastrointestinal symptoms, and other species like the Lurid Bolete require thorough cooking to break down toxins. As with other mushroom genera, proper caution is therefore advised in determining the correct species.