The nightmare of inexperienced mushroom hunters everywhere, the Destroying Angel occupies the coveted position of one of the most deadly poisonous mushrooms known to mycologists. The mushroom gets its common name from its infamously pure white fruiting body. Fortunately, it is relatively easy to identify in its mature and button stages, with a little effort. It is equipped with most of the features that a mushroom can have, including a skirt on the stem (annulus) and round cup-like base (volva). It displays a beautiful white cap, stalk, and gills, and deposits a white spore print. These white spores can be the crucial factor between life and death for someone who is trying to distinguish a Destroying Angel in its button stage from an edible, brown-spored, white button mushroom (Agaricus campestris).
Depending on what part of the world you live in, your local destroying angels will be one of a handful of similar-looking species. In our neck of the woods, northeastern North America, most white Amanitas are Amanita bisporigera, the eastern destroying angel. In western North America, you’d find the western destroying angel, Amanita ocreata, and A. smithiana (toxic in its own different way). Some angels are white forms of the infamously deadly Amanita phalloides (the latter native to Europe but introduced to North America). The names Amanita virosa and Amanita verna apply to European species, but the name A. virosa has been widely applied to just about any white Amanita. There are white Amanitas elsewhere in the world, too, and you’d best not eat any of them. For an account of what happens when you do (assuming fate is smiling on you), read Richard Eshelman’s survivor story right here at the Mushroom Blog.
In keeping with their reputation, the destroying angels employ a deadly and tricky family of toxins called amatoxins. Common to some Amanitas as well as some Galerina, Lepiota, and Conocybe species, amatoxins will cause gastrointestinal distress (diarrhea, nausea, abdominal pain) after five to twelve hours. However, symptoms typically remit after that, and one might assume that the worst has passed without going to the hospital. By the time the symptoms get worse again, after a day or two, it will probably be too late for the victim, who will likely suffer liver and kidney failure and enter a hepatic coma, ending in death. The symptoms are harsh and the ultimate treatment is severe: liver transplant. Though there is a series of experimental treatments that may or may not help, the best way to avoid being killed by amatoxin is to learn to identify the poisonous mushrooms before starting on the edible ones.
The mechanism of amatoxin toxicity is its binding to and deactivating a cellular enzyme called RNA polymerase II, which is critical in protein synthesis. The toxins actually bind within this key enzyme, preventing it from moving along the DNA strand during transcription, the process that generates messenger RNA. Transcription is most active and imperative in the liver and kidney, which feel the brunt of the toxins. All living tissues of the body are affected though, including the lining of the gastrointestinal tract and even the brain. Furthermore, only 0.1 mg/kg body weight can be a fatal dose of amatoxins, which can be found in approximately 50 grams of mushrooms. Upwards of 60% of those who consume amatoxins are killed, and some sources say that amatoxins are responsible for 95% of mushroom-related deaths, worldwide.
The best way to avoid amatoxins is to learn to identify mushrooms like A. bisporigera, and not to rely on old wives’ tales. Don’t rely on single characteristics like color or shape in isolation. Instead, look for a combination of features including the white spore print, the skirt-like ring (annulus) around the stalk, the white gills that stop just shy of the stalk, and the cup-like volva at the bottom of the stalk (often underground). Fear of destroying angels should not prevent you from mushroom hunting, as any responsible mushroom hunter can learn to identify and avoid them. The destroying angels and their deadly sister the death cap (Amanita phalloides) are awfully good mushrooms to learn first.
- Hudler, George W. 1998. Magical Mushrooms, Mischievous Molds. Princeton, NJ: Princeton University Press.
- Toxicity, mushroom- Amatoxin. eMedicine.com
- D.R. Benjamin. 1995. Mushrooms: Poisons and Panaceas. W.H. Freeman.
- Bushnell, D. A., P. Cramer, and R. D. Kornberg. 2002. Structural basis of transcription: alpha-Amanitin-RNA polymerase II cocrystal at 2.8 Ãƒâ€¦ resolution. Proceedings of the National Academy of Sciences (USA) 99:1218-1222. (geeky but readable)
Read about amatoxin effects first hand in Richard Eshelman’s memoir, “I survived the destroying angel,” right here chez nous.
Photo by K.T. Hodge of Amanita bisporigera in my own backyard.