It is popularly known as death cap. Despite its harmless appearance, Amanita phalloides is considered the most poisonous mushroom in the world (or at least one of the most dangerous), and this is no exaggeration. In fact, more than 90% of fatal mushroom poisonings are attributed to it. A small portion of this mushroom can kill an adult.
Do not be fooled by appearances, as it is quite similar to other mushrooms of the genus Amanita that are edible, such as Amanita citrina. Amanita phalloides is characterized by an olive green cap that usually measures between 5-15 cm. The lamellae are white or dyed the same color as the cap. The foot is quite long, almost white, and has a protruding white, flaccid-looking, skirt-like ring. A sac-like structure called volva appears on the underside of the foot.
Its flesh is soft and white with a greenish hue under the cuticle. Its flavor is sweet and pleasant. Adult specimens emit a slight odor that is sometimes nauseating.
This mushroom has several types of toxins:
Amatoxins: they are absorbed in the intestine and are responsible for the intoxications and severe phalloidian syndrome, which affects the liver.
Phallotoxins: although they are very toxic to liver cells, they are not absorbed by the intestine, so they contribute little to the toxicity of this mushroom. In fact, they are found in other edible species, such as Amanita rubescens.
Phallolysin: its hemolytic activity has been demonstrated in in vitro tests. However, it is susceptible to destruction by gastric acids, so its oral ingestion is not usually dangerous.
People who are poisoned by this mushroom have very characteristic symptoms that usually appear from 6-24 h after ingestion. The first symptoms are vomiting and strong and intermittent diarrhea that can lead to dehydration. In severe cases there may be hypotension, tachycardia, hypoglycemia and acidosis. In the next phase, the liver deteriorates, resulting in bloody diarrhea, delirium, convulsions and coma. Complications usually result in intracranial pressure, cerebral hemorrhage, sepsis, pancreatitis, renal failure, and cardiac arrest. Sometimes the first symptoms subside, giving a false sense of recovery, but more serious symptoms may appear later.
Accidental poisoning is avoidable, as the mushroom is relatively easy to identify, even by non-experts, although care should be taken with young specimens, as the cap is not yet extended and could be confusing.
Amanita phalloides grows in coniferous forests and in the shade of deciduous forests. It is available during autumn and early winter, although specimens have been seen as early as late summer. It is common in temperate regions of the northern hemisphere, being native to Europe and North Africa. It has been introduced accidentally in Australia, New Zealand and the United States.
THE FACT
Some famous people in history have suffered the harmful effects of this mushroom, among them the Archduke Charles of Austria (Charles VI of Habsburg), who died from accidental ingestion, or the Emperor Claudius who, according to some, was poisoned with this mushroom premeditatedly and, according to others, was accidentally intoxicated.
REFERENCES
Aritio, L.B. (1983). Records de la naturaleza. Madrid: URBION.
Fichas micológicas (2020). Amanita phalloides [online] available in: https://www.fichasmicologicas.com/?micos=1&alf=A&s=amanita%20phalloides&art=30
Petruzzello, M. (2022). 7 of the world’s most poisonous mushrooms. Encyclopedia Britannica [online] available in: https://www.britannica.com/list/7-of-the-worlds-most-poisonous-mushrooms
Talamoni, M., Cabrerizo, S., Cari, C., Díaz, M., de Rozas, M.O., Sager, I. (2006). Intoxicación por Amanita phalloides, diagnóstico y tratamiento. Arch. argent. pediatr. 104, 372-374. http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0325-00752006000400018#:~:text=Lavado%20g%C3%A1strico%2C%20respetar%20v%C3%B3mitos%20espont%C3%A1neos,siempre%20que%20no%20presente%20diarrea.
Valderrey, J.L.M. (2006). Amanita phalloides. Asturnatura [online] available in: https://www.asturnatura.com/especie/amanita-phalloides.html#:~:text=Nombre%20popular%20del%20cuerpo%20fruct%C3%ADfero%20de%20algunos%20basidiomicetes.&text=Velo%20universal%2C%20particularmente%20desarrollado%20en,sobre%20la%20superficie%20del%20sombrero.