Gyromitra esculenta, a false morel


  A skull and Crossbones OR  False morels prepared to eat with cream sauce and vegetables  ?

     Gyromitra esculenta is a little confusing when it comes to its ability to poison people.  Some people have eaten it and not felt any adverse effects; others have died soon after ingestion.  No one has figured out why it affects different people differently, but it is known that environmental factors play a huge role.  In fact, Gyromitra esculenta has relatively high concentrations of gyromitrin compared to other Gyromitra species.  The concentration of toxin varies even within the species because of variable climate, nutrition, water availability, etc.  There’s no way (yet, check when this site was updated) to know if a false morel contains enough toxin to kill you.  The lethal dose is 20-50mg/kg in adults and 10-30mg/kg in children.  So if you are going to roll the dice and eat these things, just be aware that it could go either way. 

             Gyromitrin 3D strucutre
    The name of the toxin is gyromitrin.  The 3D structure is shown above. (grey-carbon, white-hydrogen, blue-nitrogen, red-oxygen) When it was discovered that the false morel was poisonous, however, people thought it was hellvellic acid.  Gyromitrin contains small amounts of N-methyl-N-formyl hydrazine.  The structure of that compound is remarkably similar to rocket fuel.  The compound derived from hydrazine has been shown to act as a powerful carcinogen.  When its effect was tested on mice, they grew tumors over their lifetime. (Leathem, 2007)  Hydrazine prevents enzyme activation of pyridoxine, also known as vitamin B6. 

    This causes the body to not be able to break down food, and increases susceptibility to seizures.  Hydrazine is also irritating to mucous membranes and the digestive tract.  Symptoms show up 6 to 12 hours after ingestion.  They include a bloated feeling, nausea, vomiting, diarrhea, muscle cramps, and, in severe cases, seizures and death. 
A bottle of activated charcoal for medical use

    Fluid and electrolyte imbalance is the most common complication of gyromitrin poisoning, as well as seizures.  If the patient can be kept hydrated and nourished they have a better chance of recovery.  Also, administering vitamin B6 has been recommended in serious cases.  Decontamination usually isn’t necessary because people don’t seek treatment until two to six hours after being poisoned.  By that time, people have been vomiting and most of the toxin is gone.  However, a single dose of charcoal (right) is a treatment mode.

    Feeling lucky? Dice

    If you still aren’t deterred from eating these mushrooms, you should know a couple of facts about cooking them.  In theory, the toxin can be boiled off, but some may remain in the water.  Hydrazine is volatile, so it could evaporate.  Therefore, the person cooking it could inhale the toxin and be in more danger than people eating it!  Drying them before cooking can reduce the toxin concentration.  Cooking them by drying and rehydrating or boiling, rinsing, and boiling again can also help reduce the risk.  Still, it is never certain all the toxin will have been cooked off, and I don’t recommend taking that chance. 

     Now that you’ve read about the darker side of Gyromitra esculenta, visit the fun facts page for some interesting tidbits of information about this fascinating mushroom.                                                                                A young false morel
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