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mushroom poisonings

Preventing Mushroom Poisonings

Be conservative in your approach to collecting and eating wild mushrooms:

  • Collect many before you eat any
  • Use reputable local field guides
  • Join a local mycological society, and/or run your mushrooms by a local mushroom expert
  • Be cautious about where you collect mushrooms; they can absorb toxins from the environment
  • Be persnickety about mushroom quality; don’t eat old or spoiled or rotten mushrooms
  • Before collecting edibles, learn about the local, poisonous mushrooms, and be able to distinguish them, especially the few deadly species
  • Eat only mushrooms that have been positively identified - and identify every mushroom you plan to eat
  • If you can't verify every identifying characteristic, don't eat it. When in doubt, throw it out!

Other Causes of Mushroom Poisonings

When eating mushrooms, there are a few extra factors to consider:

  • Overindulgence (eat small amounts, infrequently)
  • All mushrooms should be well cooked (mushrooms can be indigestible when raw, or contain heat labile toxins, which are eliminated by cooking)
  • Trehalase deficiency (inability to digest an uncommon, highly stable mushroom sugar, trehalose)
  • Mushroom food allergies
  • Spore inhalation (has caused at least one death!)
  • Dermatitis (various mushrooms)
  • Hemolytic anemia (rare immune response to antigens in Paxillus involutus; sensitivity developed over time, rarely eaten in North America)


Here are some resources for poisons, hallucinogens, and identification:

  1. Benjamin, Denis. “Mushrooms: Poisons and Panaceas,” 1995.
  2. Stamets, Paul. “Psilocybe Mushrooms of the World,” 1996.
  3. Spoerke, David and Rumack, Barry. “Handbook of Mushroom Poisoning: Diagnosis and Treatment,” 1994.
  4. Arora, David. “Mushrooms DeMystified,” 1986.
  5. Beug, Michael. “Thirty-Plus Years of Mushroom Poisoning: Summary of the Approximately 2,000 Reports in the NAMA case registry”, McIlvianea, Vol. 16, Number 2, Fall 2006.
  6. Mushroom Toxins, “The Bad Bug Book.” Foodborne Pathogenic Microorganisms and Natural Toxins Handbook, U.S. Food and Drug Administration.

For another perspective on mycophagy, read The Mycophagists Ten Commandments.

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