POISONOUS AND HALLUCINOGENIC MUSHROOMS
by Michael W. Beug Email: beugm@evergreen.edu
The Evergreen State College, Olympia WA
Slide 14.
Gyromitra esculenta and all other Gyromitra
species are suspected of containing gyromitrin or related hydrazines. These
are Class C toxins (Poisindex III). Gyromitra esculenta, commonly
known as the beefsteak morel or brain mushroom, is a very popular mushroom
eaten by the ton in Europe and frequently eaten in North America as well.
However, Gyromitra esculenta can cause severe illness and in many
cases people have died from the effects. The quantity of toxin in the mushrooms
varies greatly with geographic region and possibly even increases with
age of the collection. Furthermore, the toxic effects are cumulative over
several days so that persons who have consumed the mushroom in moderation
for years suddenly find themselves sick after consuming Gyromitra esculenta
for several days in a row.
Unlike all of the previous toxins which are heat stable and are not
water soluble, gyromitrin is water soluble and it vaporizes on cooking.
Consequently it is partially detoxified by cooking. However, in Europe
there are several instances where cooks have become ill and sometimes have
died after inhaling the very pleasant vapors produced when Gyromitra
esculenta is cooked. The symptom onset is delayed, generally 6 to 12
hours after ingestion, though cooks can be affected in as quickly as 2
hours. Victims experience sudden headache, a bloated feeling, nausea,
vomiting, stomach pains and cramps, watery or bloody diarrhea, and fatigue
or dizziness. Seizures may ensue. The toxin produces damage mainly to the
liver, kidney, and red blood cells. A 15% mortality has been reported
with death occurring within 5-7 days.