Mushroom poisoning (also known as mycetism) refers to harmful effects from ingestion of toxic substances present in a mushroom. These symptoms can vary from slight gastrointestinal discomfort to death. The toxins present are secondary metabolites produced in specific biochemical pathways in the fungal cells. Mushroom poisoning is usually the result of ingestion of wild mushrooms after misidentification of a toxic mushroom as an edible species. The most common reason for this misidentification is close resemblance in terms of colour and general morphology of the toxic mushrooms species with edible species. Even very experienced wild mushroom gatherers are upon rare occasion poisoned by eating toxic species, despite being well aware of the risks, through carelessness.
To prevent mushroom poisoning, mushroom gatherers need to be very familiar with the mushrooms they intend to collect as well as with any similar-looking toxic species. In addition, edibility of mushrooms may depend on methods of preparation for cooking. Collectors also need to be well aware that edibility or toxicity of some species varies with geographic location.
Poisonous mushrooms contain a variety of different toxins that can differ markedly in toxicity. Symptoms of mushroom poisoning may vary from gastric upset to life-threatening organ failure resulting in death. Serious symptoms do not always occur immediately after eating; often not until the toxin attacks the kidney or liver, sometimes days or weeks later.
The most common consequence of mushroom poisoning is simply gastrointestinal upset. Most "poisonous" mushrooms contain gastrointestinal irritants which cause vomiting and diarrhea (sometimes requiring hospitalization), but usually no long-term damage. However, there are a number of recognized mushroom toxins with specific, and sometimes deadly, effects:
- Alpha-amanitin (deadly: causes liver damage 1–3 days after ingestion)–principal toxin in genus Amanita.
- Phallotoxin (causes gastrointestinal upset)–also found in poisonous Amanitas
- Orellanine (deadly: causes kidney failure within 3 weeks after ingestion)–principal toxin in genus Cortinarius.
- Muscarine (sometimes deadly: can cause respiratory failure)–found in genus Omphalotus.
- Gyromitrin (deadly: causes neurotoxicity, gastrointestinal upset, and destruction of blood cells)–principal toxin in genus Gyromitra.
- Coprine (causes illness when consumed with alcohol)–principal toxin in genus Coprinus.
- Ibotenic acid and muscimol (hallucinogenic)–principal toxin in A. muscaria, A. pantherina, and A. gemmata.
- Psilocybin and psilocin (hallucinogenic)–principal 'toxin' in genus Psilocybe.
- Arabitol (causes gastrointestinal irritation in some people).
- Bolesatine a toxin found in Boletus satanas
- Ergotamine (deadly: affects the vascular system and can lead to loss of limbs and death): An alkaloid found in genus Claviceps.
Symptoms of mushroom poisoning vary depending on the toxins involved.
- Alpha-amanitin: For 6–12 hours, there are no symptoms. This is followed by a period of gastrointestinal upset (vomiting and profuse, watery diarrhea). This stage is caused primarily by the phallotoxins and typically lasts 24 hours. At the end of this second stage is when severe liver damage begins. The damage may continue for another 2–3 days. Kidney damage can also occur. Some patients will require a liver transplant. Amatoxins are found in some mushrooms in the genus Amanita, but are also found in some species of Galerina and Lepiota. Overall, mortality is between 10 and 15 percent. Recently, Silybum marianum or blessed milk thistle has been shown to protect the liver from amanita toxins and promote regrowth of damaged cells, including a study in which 60 patients exposed to death cap poison were given 20 mg/kg of milk thistle seeds per day within 48 hours of consuming the deadly mushrooms. None of the patients died.
- Orellanine: This toxin causes no symptoms for 3–20 days after ingestion. Typically around day 11, the process of kidney failure begins, and is usually symptomatic by day 20. These symptoms can include pain in the area of the kidneys, thirst, vomiting, headache, and fatigue. A few species in the very large genus Cortinarius contain this toxin. People who have eaten mushrooms containing orellanine may experience early symptoms as well, because the mushrooms often contain other toxins in addition to orellanine. A related toxin that causes similar symptoms but within 3–6 days has been isolated from Amanita smithiana and some other related toxic Amanitas.
- Muscarine: Muscarine stimulates the muscarinic receptors of the nerves and muscles. Symptoms include sweating, salivation, tears, blurred vision, palpitations, and, in high doses, respiratory failure. Muscarine is found in mushrooms of the genus Omphalotus, notably the Jack o' Lantern mushrooms. It is also found in A. muscaria, although it is now known that the main effect of this mushroom is caused by ibotenic acid. Muscarine can also be found in some Inocybe species and Clitocybe species, particularly Clitocybe dealbata, and some red-pored Boletes.
- Gyromitrin: Stomach acids convert gyromitrin to monomethylhydrazine (MMH), a compound employed in rocket fuel. It affects multiple body systems. It blocks the important neurotransmitter GABA, leading to stupor, delirium, muscle cramps, loss of coordination, tremors, and/or seizures. It causes severe gastrointestinal irritation, leading to vomiting and diarrhea. In some cases, liver failure has been reported. It can also cause red blood cells to break down, leading to jaundice, kidney failure, and signs of anemia. It is found in mushrooms of the genus Gyromitra. A gyromitrin-like compound has also been identified in mushrooms of the genus Verpa.
- Coprine: Coprine is metabolized to a chemical that resembles disulfiram. It inhibits aldehyde dehydrogenase (ALDH), which generally causes no harm, unless the person has alcohol in their bloodstream while ALDH is inhibited. This can happen if alcohol is ingested shortly before or up to a few days after eating the mushrooms. In that case the alcohol cannot be completely metabolized, and the person will experience flushed skin, vomiting, headache, dizziness, weakness, apprehension, confusion, palpitations, and sometimes trouble breathing. Coprine is found mainly in mushrooms of the genus Coprinus, although similar effects have been noted after ingestion of Clitocybe clavipes.
- Ibotenic acid: This organic acid is metabolized to muscimol. The effects of muscimol vary, but nausea and vomiting are common. Confusion, euphoria, or sleepiness are possible. Loss of muscular coordination, sweating, and chills are likely. Some people experience visual distortions, a feeling of strength, or delusions. Symptoms normally appear after 30 minutes to 2 hours and last for several hours. A. muscaria, the "Alice in Wonderland" mushroom, is known for the toxic/hallucinogenic properties caused by ibotenic acid, but A. pantherina and A. gemmata also contain the same compound. While normally self-limiting, fatalities have been associated with A. pantherina, and consumption of a large number of any of these mushrooms is likely to be dangerous.
- Psilocybin: This compound is converted into psilocin when ingested. Symptoms begin shortly after ingestion. The effects can include euphoria, visual and religious hallucinations, and heightened perception. However, some persons experience fear, agitation, confusion, and schizophrenialike symptoms. All symptoms generally pass after several hours. Some (though not all) members of the genus Psilocybe contain psilocybin, as do some Panaeolus, Copelandia, Conocybe, Gymnopilus, and others. Some of these mushrooms also contain baeocystin, which has effects similar to psilocin.
- Arabitol: A sugar alcohol, similar to mannitol, which causes no harm in most people but causes gastrointestinal irritation in some. It is found in small amounts in oyster mushrooms, and considerable amounts in Suillus species and Hygrophoropsis aurantiaca (the "false chanterelle").
Some mushrooms contain less toxic compounds and, therefore, are not severely poisonous. Poisonings by these mushrooms may respond well to treatment. However, certain types of mushrooms, such as the Amanitas, contain very potent toxins and are very poisonous; so even if symptoms are treated promptly mortality is high. With some toxins, death can occur in a week or a few days. Although a liver or kidney transplant may save some patients with complete organ failure, in many cases there are no organs available. Patients who are hospitalized and given aggressive support therapy almost immediately after ingestion of amanitin-containing mushrooms have a mortality rate of only 10%, whereas those admitted 60 or more hours after ingestion have a 50–90% mortality rate.
Cap is convex or spread with a slight concavity or convexity, white color with yellowish brown tones,the stem is hairy flaky,white color,growing in the autumn in all forests.
Cap is convex and bulging then it spread and depressed, white with yellow ocher shades,stem is longitudinally grooved,
white ocher color,growing in late summer and autumn in the deciduous and coniferous forests on fallen leaves and needles.
Cap a convex then spread, smooth and shiny surfaces, scarlet red,the stem of scarlet red color,growing in late summer and autumn, the deciduous beech forests.
Cap a convex then spread and truncate, velvety surface, the edge rolled, varies from reddish yellow to olive-brown and
olive-green,stem is yellowish olive colors, growing in late summer and autumn in the coniferous and deciduous forests.
Cap is conical, then a conical and sharply bulging, yellow-orange to reddish brown, cap surface is covered with scales,
stipe of ocher brown in color, black root, growing in late summer in deciduous forests.
Cap is conical, then spread and dull bulging, reddish brown or orange-brown, very thin cap, stipe dirty yellow, grows in the
summer and autumn in the deciduous forests.
Cap is a convex conical, then spread and dull bulging,the edge is wavy and cracks,brown to reddish brown color, very thin cap, stipe dirty yellow or rusty red color, grows in the summer and autumn in the deciduous
Cap is conical, then spread and strongly bulging, rusted or orange-brown, rolled edge, stipe yellow rust, to grow in late
summer in coniferous forests.
Cap is convex then widespread, the edge is rolled and wavy, golden yellow color with some reddish freckles, a stem of sulfur yellow with brown longitudinal fibers, growing in deciduous forests.
Cap is spread and bulging, gray color,edge is wrapped,sinuous and covered with small flakes,stem is white color, sometimes the surface is covered with flakes,growing in summer and autumn
in the deciduous forests along the edges of forests.
Cap is convex then spread, covered with scales,gray or gray-brown color,the edge is inrolled,stem is robust,is full
,white and gently ocher color,growing in late summer and autumn in the deciduous and coniferous forests,especially under
spruce and beech.