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Mushroom poisoning is
poisoning Poisoning is the harmful effect which occurs when Toxicity, toxic substances are introduced into the body. The term "poisoning" is a derivative of poison, a term describing any chemical substance that may harm or kill a living organism upon ...
resulting from the
ingestion Ingestion is the consumption of a substance by an organism. In animals, it normally is accomplished by taking in a substance through the mouth into the gastrointestinal tract, such as through eating or drinking. In single-celled organisms, inge ...
of
mushroom A mushroom or toadstool is the fleshy, spore-bearing Sporocarp (fungi), fruiting body of a fungus, typically produced above ground on soil or another food source. ''Toadstool'' generally refers to a poisonous mushroom. The standard for the n ...
s that contain
toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...
substances.
Symptoms Signs and symptoms are diagnostic indications of an illness, injury, or condition. Signs are objective and externally observable; symptoms are a person's reported subjective experiences. A sign for example may be a higher or lower temperature ...
can vary from slight
gastrointestinal The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascular system. ...
discomfort to
death Death is the end of life; the irreversible cessation of all biological functions that sustain a living organism. Death eventually and inevitably occurs in all organisms. The remains of a former organism normally begin to decompose sh ...
in about 10 days. Mushroom
toxin A toxin is a naturally occurring poison produced by metabolic activities of living cells or organisms. They occur especially as proteins, often conjugated. The term was first used by organic chemist Ludwig Brieger (1849–1919), derived ...
s are
secondary metabolite Secondary metabolites, also called ''specialised metabolites'', ''secondary products'', or ''natural products'', are organic compounds produced by any lifeform, e.g. bacteria, archaea, fungi, animals, or plants, which are not directly involved ...
s produced by the
fungus A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...
. 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 a close resemblance in terms of color and general
morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...
of the toxic mushrooms species with edible species. To prevent mushroom poisoning, mushroom gatherers familiarize themselves with the mushrooms they intend to collect, as well as with any similar-looking toxic species. The safety of eating wild mushrooms may depend on methods of preparation for cooking. Some toxins, such as
amatoxin Amatoxins are a subgroup of at least nine related cyclic peptide toxins found in three genera of deadly poisonous mushrooms (''Amanita'', '' Galerina'' and '' Lepiota'') and one species of the genus '' Pholiotina''. Amatoxins are very potent, as li ...
s, are
thermostable In materials science and molecular biology, thermostability is the ability of a substance to resist irreversible change in its chemical or physical structure, often by resisting decomposition or polymerization, at a high relative temperature. Th ...
and mushrooms containing such toxins will not be rendered safe to eat by cooking.


Signs and symptoms

Poisonous mushrooms contain a variety of different toxins that can differ markedly in toxicity. Symptoms of mushroom poisoning may vary from gastric upset to 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 that cause
vomiting Vomiting (also known as emesis, puking and throwing up) is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteritis, pre ...
and
diarrhea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...
(sometimes requiring urgent care ), but usually no long-term damage. However, there are a number of recognized mushroom toxins with specific, and sometimes deadly, effects: The period between ingestion and the onset of symptoms varies dramatically between toxins, some taking days to show symptoms identifiable as mushroom poisoning. *
α-Amanitin α-Amanitin (''alpha''-Amanitin) is a cyclic peptide of eight amino acids. It is possibly the most deadly of all the amatoxins, toxins found in several species of the mushroom genus ''Amanita'', one being the death cap (''Amanita phalloides'') as ...
: 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 ''Lepiota'' is a genus of gilled mushrooms in the family Agaricaceae. All ''Lepiota'' species are ground-dwelling saprotrophs with a preference for rich, calcareous soils. Basidiocarps (fruit bodies) are agaricoid with whitish spores, typica ...
''. Overall, mortality is between 10 and 15 percent. in: Recently, ''Silybum marianum'' or blessed milk thistle has been shown to protect the liver from amanita toxins and promote regrowth of damaged cells. *
Orellanine Orellanine or orellanin is a mycotoxin found in a group of mushrooms known as the Orellani within the family Cortinariaceae. Structurally, it is a pyridine N-oxide, bipyridine N-oxide compound somewhat related to the herbicide diquat. History Ore ...
: This toxin generally 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 A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...
, and
fatigue Fatigue is a state of tiredness (which is not sleepiness), exhaustion or loss of energy. It is a signs and symptoms, symptom of any of various diseases; it is not a disease in itself. Fatigue (in the medical sense) is sometimes associated wit ...
. A few species in the very large genus ''
Cortinarius ''Cortinarius'' is a globally distributed genus of fungus in the family Cortinariaceae. Its members are commonly known by the names cortinar and webcap. It is suspected to be the largest genus of agarics, containing over 2,000 widespread species ...
'' contain this toxin. People having 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 ''Amanita smithiana'', also known as Smith's amanita, is a species of agaric found on soil in coniferous (''Abies'', ''Tsuga'', ''Pseudotsuga'') and broadleaved (''Alnus'', ''Quercus'') woodland in the Pacific Northwest of North America. It frui ...
'' and some other related toxic ''Amanita''s. *
Muscarine Muscarine, L-(+)-muscarine, or muscarin is a Secondary metabolite, natural product found in certain mushrooms, particularly in ''Inocybe'' and ''Clitocybe'' species, such as the deadly ''Clitocybe dealbata, C. dealbata''. Mushrooms in the g ...
: Muscarine stimulates the
muscarinic receptors Muscarinic acetylcholine receptors (mAChRs) are acetylcholine receptors that form G protein-coupled receptor complexes in the cell membranes of certain neurons and other cells. They play several roles, including acting as the main end-recep ...
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 ''Inocybe'' is a genus of mushroom-forming fungi, with over 1,000 species. Its members are mycorrhizal, and some evidence shows that the high degree of speciation is due to adaptation to different trees and possibly also local habitats. Taxonomy ...
'' species and ''
Clitocybe ''Clitocybe'' is a genus of mushrooms characterized by white, off-white, buff, cream, pink, or light-yellow spores, gills running down the stem, and pale white to brown or lilac coloration. They are primarily saprotrophic, decomposing forest grou ...
'' species, in particular ''
Clitocybe dealbata ''Clitocybe'' is a genus of mushrooms characterized by white, off-white, buff, cream, pink, or light-yellow spores, gills running down the stem, and pale white to brown or lilac coloration. They are primarily saprotrophic, decomposing forest gro ...
'', and some red-pored ''
Boletes A bolete is a type of mushroom, or fungal fruiting body. It can be identified thanks to a unique cap. On the underside of the cap there is usually a spongy surface with pores, instead of the gills typical of mushrooms. A similar pore surface is ...
.'' *
Gyromitrin Gyromitrin is a toxin and carcinogen present in several members of the fungal genus '' Gyromitra'', like '' G. esculenta''. Its formula is . It is unstable and is easily hydrolyzed to the toxic compound monomethylhydrazine . Monomethylhydraz ...
: Stomach acids convert gyromitrin to
monomethylhydrazine Monomethylhydrazine (MMH) is a highly toxic, volatile hydrazine derivative with the chemical formula . It is used as a rocket propellant in bipropellant rocket engines because it is hypergolic with various oxidizers such as nitrogen tetroxide () ...
(MMH). It affects multiple body systems. It blocks the important neurotransmitter
GABA GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GA ...
, leading to
stupor Stupor is the lack of critical mental function and a level of consciousness, in which an affected person is almost entirely unresponsive and responds only to intense stimuli such as pain. The word derives from the Latin '' stupor'' ("numbness, in ...
,
delirium Delirium (formerly acute confusional state, an ambiguous term that is now discouraged) is a specific state of acute confusion attributable to the direct physiological consequence of a medical condition, effects of a psychoactive substance, or ...
, muscle cramps, loss of coordination,
tremor A tremor is an involuntary, somewhat rhythmic muscle contraction and relaxation involving neural oscillations, oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the h ...
s, and/or
seizures A seizure is a sudden, brief disruption of brain activity caused by abnormal, excessive, or synchronous neuronal firing. Depending on the regions of the brain involved, seizures can lead to changes in movement, sensation, behavior, awareness, o ...
. 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 Jaundice, also known as icterus, is a yellowish or, less frequently, greenish pigmentation of the skin and sclera due to high bilirubin levels. Jaundice in adults is typically a sign indicating the presence of underlying diseases involving ...
, kidney failure, and signs of
anemia Anemia (also spelt anaemia in British English) is a blood disorder in which the blood has a reduced ability to carry oxygen. This can be due to a lower than normal number of red blood cells, a reduction in the amount of hemoglobin availabl ...
. It is found in mushrooms of the genus ''Gyromitra''. A gyromitrin-like compound has also been identified in mushrooms of the genus ''
Verpa ''Verpa'' is a genus of ascomycete fungi related to the morels. Resembling the latter genus in edibility and form, the common name early morels is popular. There are five species in the widespread genus. Taxonomy Analysis of the ribosomal DNA o ...
''. *
Coprine Coprine is a mycotoxin. It was first isolated from common inkcap (''Coprinopsis atramentaria''). It occurs in mushrooms in the genera '' Coprinopsis''. When combined with alcohol, it causes "Coprinus syndrome". It inhibits the enzyme aldehyde de ...
: Coprine is metabolized to a chemical that resembles
disulfiram Disulfiram is a medication used to support the treatment of chronic alcoholism by producing an acute sensitivity to ethanol (drinking alcohol). Disulfiram works by Enzyme inhibition, inhibiting the enzyme aldehyde dehydrogenase (specifically ALD ...
. It inhibits
aldehyde dehydrogenase Aldehyde dehydrogenases () are a group of enzymes that catalyse the oxidation of aldehydes. They convert aldehydes (R–C(=O)) to carboxylic acids (R–C(=O)). The oxygen comes from a water molecule. To date, nineteen ALDH genes have ...
(ALDH), which, in general, 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 A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...
,
dizziness Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to Balance disorder, disequilibrium or a non-specific feeling, such as giddiness or foolishness. Dizziness is a ...
, weakness, apprehension, confusion, palpitations, and sometimes trouble to breathe. Coprine is found mainly in mushrooms of the genus ''
Coprinus ''Coprinus'' is a small genus of mushroom-forming fungi consisting of '' Coprinus comatus''the shaggy ink cap (British) or shaggy mane ( American)and several of its close relatives. Until 2001, ''Coprinus'' was a large genus consisting of all a ...
'', although similar effects have been noted after ingestion of '' Clitocybe clavipes''. *
Ibotenic acid Ibotenic acid or (''S'')-2-amino-2-(3-hydroxyisoxazol-5-yl)acetic acid, also referred to as ibotenate, is a naturally occurring alpha-amino acid found in certain ''Amanita'' mushrooms, that primarily acts as a potent glutamate receptor agonist ...
: Decarboxylates into
muscimol Muscimol, also known as agarin or pantherine, as well as 5-(aminomethyl)-1,2-oxazol-3-ol, is the principal psychoactive constituent of ''Amanita muscaria'' and '' Amanita pantherina''. Muscimol is an isoxazole alkaloid and a potent and selectiv ...
upon ingestion. 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 hallucinatory experiences caused by muscimol, 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. *
Arabitol Arabitol, or arabinitol, is a sugar alcohol. It can be formed by the reduction of either arabinose or lyxose. Some organic acid tests check for the presence of D-arabitol, which may indicate overgrowth of intestinal microbes such as '' Candida ...
: A
sugar alcohol Sugar alcohols (also called polyhydric alcohols, polyalcohols, alditols or glycitols) are organic compounds, typically derived from sugars, containing one hydroxyl group attached to each carbon atom. They are white, water-soluble solids that c ...
, 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 ''Pleurotus'' is a genus of gilled mushrooms which includes one of the most widely eaten mushrooms, '' P. ostreatus''. Species of ''Pleurotus'' may be called oyster, abalone, or tree mushrooms, and are some of the most commonly cultivated ...
, and considerable amounts in ''
Suillus ''Suillus'' is a genus of basidiomycete fungi in the family Suillaceae and order Boletales. Species in the genus are associated with trees in the pine family (Pinaceae), and are mostly distributed in temperate locations in the Northern Hemisphe ...
'' species and ''
Hygrophoropsis aurantiaca ''Hygrophoropsis aurantiaca'', commonly known as the false chanterelle, is a species of fungus in the family Hygrophoropsidaceae. Austrian naturalist Franz Xaver von Wulfen described the false chanterelle in 1781, noting both its resemblance w ...
'' (the " false chanterelle").


Causes

New species of fungi are continuing to be discovered, with an estimated number of 800 new species registered annually. This, added to the fact that many investigations have recently reclassified some species of mushrooms from edible to poisonous has made older classifications insufficient at describing what now is known about the different species of fungi that are harmful to humans. It is now thought that of the approximately 100,000 known fungi species found worldwide, about 100 of them are poisonous to humans. However, by far the majority of mushroom poisonings are not fatal, and the majority of fatal poisonings are attributable to the ''
Amanita phalloides ''Amanita phalloides'' ( ), commonly known as the death cap, is a deadly poisonous basidiomycete fungus and mushroom, one of many in the genus ''Amanita''. Originating in Europe but later introduced to other parts of the world since the late ...
'' mushroom. A majority of these cases are due to mistaken identity. This is a common occurrence with ''A. phalloides'' in particular, due to its resemblance to the Asian paddy-straw mushroom, ''
Volvariella volvacea ''Volvariella volvacea'' (also known as paddy straw mushroom or straw mushroom) is a species of edible mushroom cultivated throughout East and Southeast Asia and used extensively in Asian cuisine. They are often available fresh in regions they ar ...
''. Both are light-colored and covered with a
universal veil In mycology, a universal veil is a temporary membranous tissue that fully envelops immature fruiting bodies of certain gilled mushrooms. The developing Caesar's mushroom (''Amanita caesarea''), for example, which may resemble a small white sph ...
when young. ''
Amanita The genus ''Amanita'' contains about 600 species of agarics, including some of the most toxic known mushrooms found worldwide, as well as some well-regarded Edible mushroom, edible species (and many species of unknown edibility). The genus is re ...
s'' can be mistaken for other species, as well, in particular when immature. On at least one occasion they have been mistaken for ''
Coprinus comatus ''Coprinus comatus'', commonly known as the shaggy ink cap, lawyer's wig, or shaggy mane, is a species of fungus. The young fruit bodies first appear as white cylinders emerging from the ground, then the bell-shaped caps open out. The white ca ...
''. In this case, the victim had some limited experience in identifying mushrooms, but did not take the time to correctly identify these particular mushrooms until after he began to experience symptoms of mushroom poisoning. The author of ''Mushrooms Demystified'', David Arora cautions
puffball Puffballs are a type of fungus featuring a ball-shaped fruit body that (when mature) bursts on contact or impact, releasing a cloud of dust-like spores into the surrounding area. Puffballs belong to the division Basidiomycota and encompass sever ...
-hunters to beware of ''Amanita'' "eggs", which are ''Amanita''s still entirely encased in their universal veil. ''Amanita''s at this stage are difficult to distinguish from puffballs. Foragers are encouraged to always cut the fruiting bodies of suspected puffballs in half, as this will reveal the outline of a developing ''Amanita'' should it be present within the structure. A majority of mushroom poisonings, in general, are the result of small children, especially toddlers in the "grazing" stage, ingesting mushrooms found on the lawn. While this can happen with any mushroom, ''
Chlorophyllum molybdites ''Chlorophyllum molybdites'', commonly known as the green-spored parasol, false parasol, green-spored lepiota and vomiter, is a common species of mushroom found in temperate and subtropical meadows and lawns. The species is poisonous and produ ...
'' is often implicated due to its preference for growing in lawns. ''C. molybdites'' causes severe gastrointestinal upset but is not considered deadly poisonous. A few poisonings are the result of misidentification while attempting to collect hallucinogenic mushrooms for recreational use. In 1981, one fatality and two hospitalizations occurred following consumption of ''
Galerina marginata ''Galerina marginata'', known colloquially as funeral bell, deadly skullcap, autumn skullcap or deadly galerina, is a species of extremely poisonous mushroom-forming fungus in the family Hymenogastraceae of the order Agaricales. Before 2001, th ...
'', mistaken for a ''
Psilocybe ''Psilocybe'' ( ) is a genus of gilled mushrooms, growing worldwide, in the family Hymenogastraceae. Many species contain the Psychedelic drug, psychedelic compounds psilocybin and psilocin. Taxonomy Taxonomic history A 2002 study of the ...
'' species. ''
Galerina ''Galerina'' is a genus of small brown-spore saprobic mushroom-bearing fungi, with over 300 species found throughout the world from the far north to remote Macquarie Island in the Southern Ocean. The genus is most noted for some extremely poison ...
'' and ''Psilocybe'' species are both small, brown, and sticky, and can be found growing together. However, ''Galerina'' contains
amatoxins Amatoxins are a subgroup of at least nine related cyclic peptide toxins found in three genera of deadly poisonous mushrooms (''Amanita'', '' Galerina'' and '' Lepiota'') and one species of the genus '' Pholiotina''. Amatoxins are very potent, as li ...
, the same poison found in the deadly ''Amanita'' species. Another case reports kidney failure following ingestion of ''
Cortinarius orellanus ''Cortinarius orellanus'', commonly known as the fool's webcap or fools webcap, is a species of deadly fungus in the family Cortinariaceae native to Europe. Within the genus it belongs to a group known as the Orellani, all of which are highly ...
'', a mushroom containing
orellanine Orellanine or orellanin is a mycotoxin found in a group of mushrooms known as the Orellani within the family Cortinariaceae. Structurally, it is a pyridine N-oxide, bipyridine N-oxide compound somewhat related to the herbicide diquat. History Ore ...
. It is natural that accidental ingestion of hallucinogenic species also occurs, but is rarely harmful when ingested in small quantities. Cases of serious toxicity have been reported in small children. ''
Amanita pantherina ''Amanita pantherina'', also known as the panther cap, false blusher, and the panther amanita due to its similarity to the true blusher (''Amanita rubescens''), is a species of fungus found in Eurasia with poisonous and psychoactive propertie ...
'', while containing the same hallucinogens as ''
Amanita muscaria ''Amanita muscaria'', commonly known as the fly agaric or fly amanita, is a basidiomycete fungus of the genus ''Amanita''. It is a large white-lamella (mycology), gilled, white-spotted mushroom typically featuring a bright red cap covered with ...
'' (e.g.,
ibotenic acid Ibotenic acid or (''S'')-2-amino-2-(3-hydroxyisoxazol-5-yl)acetic acid, also referred to as ibotenate, is a naturally occurring alpha-amino acid found in certain ''Amanita'' mushrooms, that primarily acts as a potent glutamate receptor agonist ...
and
muscimol Muscimol, also known as agarin or pantherine, as well as 5-(aminomethyl)-1,2-oxazol-3-ol, is the principal psychoactive constituent of ''Amanita muscaria'' and '' Amanita pantherina''. Muscimol is an isoxazole alkaloid and a potent and selectiv ...
), has been more commonly associated with severe gastrointestinal upset than its better-known counterpart. Although usually not fatal, ''
Omphalotus ''Omphalotus'' is a genus of basidiomycete mushroom, in the family Omphalotaceae, formally circumscription (taxonomy), circumscribed by Victor Fayod in 1889. Members have the traditional pileus (mycology), cap and stipe (mycology), stem structu ...
'' spp., "Jack-o-lantern mushrooms", are another cause of sometimes significant toxicity. They are sometimes mistaken for
chanterelle Chanterelle is the common name of several species of fungi in the genera ''Cantharellus'', ''Craterellus'', ''Gomphus (fungus), Gomphus'', and ''Polyozellus''. They are orange, yellow or white, meaty and funnel-shaped. On the lower surface, mos ...
s. Both are bright-orange and fruit at the same time of year, although ''Omphalotus'' grows on wood and has true gills rather than the veins of a ''
Cantharellus ''Cantharellus'' is a genus of mushrooms, commonly known as chanterelles (), a name which can also refer to the type species, '' Cantharellus cibarius''. They are mycorrhizal fungi, meaning they form symbiotic associations with plants. Ch ...
''. They contain toxins known as illudins, which causes gastrointestinal symptoms. Bioluminescent species are generally inedible and often mildly toxic. ''
Clitocybe dealbata ''Clitocybe'' is a genus of mushrooms characterized by white, off-white, buff, cream, pink, or light-yellow spores, gills running down the stem, and pale white to brown or lilac coloration. They are primarily saprotrophic, decomposing forest gro ...
'', which is occasionally mistaken for an
oyster mushroom ''Pleurotus'' is a genus of Gill (mushroom), gilled mushrooms which includes one of the most widely eaten mushrooms, ''Pleurotus ostreatus, P. ostreatus''. Species of ''Pleurotus'' may be called oyster, abalone, or tree mushrooms, and are ...
or other edible species contains
muscarine Muscarine, L-(+)-muscarine, or muscarin is a Secondary metabolite, natural product found in certain mushrooms, particularly in ''Inocybe'' and ''Clitocybe'' species, such as the deadly ''Clitocybe dealbata, C. dealbata''. Mushrooms in the g ...
. Toxicities can also occur with collection of
morels ''Morchella'', the true morels, is a genus of edible sac fungi closely related to anatomically simpler cup fungi in the order Pezizales ( division Ascomycota). These distinctive fungi have a honeycomb appearance due to the network of ridges w ...
. Even true morels, if eaten raw, will cause gastrointestinal upset. Typically, morels are thoroughly cooked before eating. ''
Verpa bohemica ''Verpa bohemica'' is a species of fungus in the family Morchellaceae. The synonym ''Ptychoverpa bohemica'' is often used by European mycologists and it is commonly known as the early morel or the wrinkled thimble-cap. The mushroom has a pale ye ...
'', although referred to as "thimble morels" or "early morels" by some, have caused toxic effects in some individuals. ''
Gyromitra ''Gyromitra'' () is a genus of about 18 species of ascomycete fungi. They are a false morel - a frequently toxic mushroom that can be mistaken for edible mushrooms of the genus ''Morchella'' (morels). Taxonomy The name ''Gyromitra'' comes from ...
'' spp., " false morels", are deadly poisonous if eaten raw. They contain a toxin called
gyromitrin Gyromitrin is a toxin and carcinogen present in several members of the fungal genus '' Gyromitra'', like '' G. esculenta''. Its formula is . It is unstable and is easily hydrolyzed to the toxic compound monomethylhydrazine . Monomethylhydraz ...
, which can cause
neurotoxicity Neurotoxicity is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specifical ...
, gastrointestinal toxicity, and destruction of the blood cells. The
Finns Finns or Finnish people (, ) are a Baltic Finns, Baltic Finnic ethnic group native to Finland. Finns are traditionally divided into smaller regional groups that span several countries adjacent to Finland, both those who are native to these cou ...
consume ''
Gyromitra esculenta ''Gyromitra esculenta'' is an ascomycete fungus from the genus ''Gyromitra'', widely distributed across Europe and North America. It normally fruits in sandy soils under coniferous trees in spring and early summer. The Ascocarp, fruiting bod ...
'' after
parboiling Parboiling (or leaching) is the partial or semi boiling of food as the first step in cooking. The word is from the Old French ''parbouillir'', 'to boil thoroughly' but by mistaken association with "part", it has acquired this definition. The w ...
, but this may not render the mushroom entirely safe, resulting in its being called the "
fugu Fugu (; ; ) in Japanese language, Japanese, ''bogeo'' (; 鰒魚) or ''bok'' () in Korean language, Korean, and ''hétún'' () in Standard Modern Chinese refers to tetraodontidae, pufferfish, normally of the genus ''Takifugu'', ''Lagocephalus'', o ...
of the Finnish cuisine". A more unusual toxin is
coprine Coprine is a mycotoxin. It was first isolated from common inkcap (''Coprinopsis atramentaria''). It occurs in mushrooms in the genera '' Coprinopsis''. When combined with alcohol, it causes "Coprinus syndrome". It inhibits the enzyme aldehyde de ...
, a
disulfiram Disulfiram is a medication used to support the treatment of chronic alcoholism by producing an acute sensitivity to ethanol (drinking alcohol). Disulfiram works by Enzyme inhibition, inhibiting the enzyme aldehyde dehydrogenase (specifically ALD ...
-like compound that is harmless unless ingested within a few days of ingesting alcohol. It inhibits
aldehyde dehydrogenase Aldehyde dehydrogenases () are a group of enzymes that catalyse the oxidation of aldehydes. They convert aldehydes (R–C(=O)) to carboxylic acids (R–C(=O)). The oxygen comes from a water molecule. To date, nineteen ALDH genes have ...
, an enzyme required for breaking down
alcohol Alcohol may refer to: Common uses * Alcohol (chemistry), a class of compounds * Ethanol, one of several alcohols, commonly known as alcohol in everyday life ** Alcohol (drug), intoxicant found in alcoholic beverages ** Alcoholic beverage, an alco ...
. Thus, the symptoms of toxicity are similar to being
hung over A hangover is the experience of various unpleasant physiological and psychological effects usually following the consumption of alcohol, such as wine, beer, and liquor. Hangovers can last for several hours or for more than 24 hours. Typical s ...
—flushing, headache, nausea, palpitations, and, in severe cases, trouble breathing. ''
Coprinus ''Coprinus'' is a small genus of mushroom-forming fungi consisting of '' Coprinus comatus''the shaggy ink cap (British) or shaggy mane ( American)and several of its close relatives. Until 2001, ''Coprinus'' was a large genus consisting of all a ...
'' species, including ''
Coprinopsis atramentaria ''Coprinopsis atramentaria'', commonly known as the common ink cap, tippler's bane, or inky cap, is a species of fungus. Previously known as ''Coprinus atramentarius'', it is the second best-known ink cap and previous member of the genus '' ...
'', contain coprine. ''
Coprinus comatus ''Coprinus comatus'', commonly known as the shaggy ink cap, lawyer's wig, or shaggy mane, is a species of fungus. The young fruit bodies first appear as white cylinders emerging from the ground, then the bell-shaped caps open out. The white ca ...
'' does not, but it is best to avoid mixing alcohol with other members of this genus. Recently, poisonings have also been associated with ''
Amanita smithiana ''Amanita smithiana'', also known as Smith's amanita, is a species of agaric found on soil in coniferous (''Abies'', ''Tsuga'', ''Pseudotsuga'') and broadleaved (''Alnus'', ''Quercus'') woodland in the Pacific Northwest of North America. It frui ...
''. These poisonings may be due to orellanine, but the onset of symptoms occurs in 4 to 11 hours, which is much quicker than the 3 to 20 days normally associated with orellanine. ''
Paxillus involutus ''Paxillus involutus'', also known as the brown roll-rim or the common roll-rim, is a species of basidiomycete fungus. Although it has lamella (mycology), gills, it is more closely related to the pored boletes than to typical gilled mushroom ...
'' is also inedible when raw, but is eaten in Europe after pickling or parboiling. However, after the death of the German mycologist Dr. Julius Schäffer, it was discovered that the mushroom contains a toxin that can stimulate the immune system to attack its red blood cells. This reaction is rare but can occur even after safely eating the mushroom for many years. Similarly, ''
Tricholoma equestre ''Tricholoma equestre'' or ''Tricholoma flavovirens'', commonly known as the man on horseback or yellow knight, is a species of fungus of the genus '' Tricholoma'' that forms ectomycorrhiza with pine trees. It has been treasured as an edible mu ...
'' was widely considered edible and good, until it was connected with rare cases of
rhabdomyolysis Rhabdomyolysis (shortened as rhabdo) is a condition in which damaged skeletal muscle breaks down rapidly. Symptoms may include muscle pains, weakness, vomiting, and confusion. There may be tea-colored urine or an irregular heartbeat. Some o ...
. In the fall of 2004, thirteen deaths were associated with consumption of ''
Pleurocybella porrigens ''Pleurocybella porrigens'', also known as the angel wing, is a species of fungus in the family Phyllotopsidaceae. It medium-sized fruit bodies are whitish and fan-shaped. It is a wood-decay fungus on conifer wood and is widespread in temperate ...
'' or "angel's wings". In general, these mushrooms are considered edible. All the victims died of an acute brain disorder, and all had pre-existing kidney disease. The exact cause of the toxicity was not known at this time and the deaths cannot be definitively attributed to mushroom consumption. However, mushroom poisoning is not always due to mistaken identity. For example, the highly toxic ergot ''
Claviceps purpurea ''Claviceps purpurea'' is an ergot fungus that grows on the ear (botany), ears of rye and related cereal and forage plants. Consumption of Cereal, grains or seeds contaminated with the survival structure of this fungus, the ergot sclerotium, can ...
'', which grows on rye, is sometimes ground up with rye, unnoticed, and later consumed. This can cause devastating, even fatal, effects, called
ergotism Ergotism (pron. ) is the effect of long-term ergot poisoning, traditionally due to the ingestion of the alkaloids produced by the '' Claviceps purpurea'' fungus—from the Latin "club" or clavus "nail" and for "head", i.e. the purple club-h ...
. Cases of
idiosyncratic An idiosyncrasy is a unique feature of something. The term is often used to express peculiarity. Etymology The term "idiosyncrasy" originates from Greek ', "a peculiar temperament, habit of body" (from ', "one's own", ', "with" and ', "blend ...
or unusual reactions to fungi can also occur. Some are probably due to allergy, others to some other kind of sensitivity. It is not uncommon for a person to experience gastrointestinal upset associated with one particular mushroom species or genus. Some mushrooms might concentrate toxins from their growth substrate, such as
Chicken of the Woods ''Laetiporus'' is a genus of edible mushrooms found throughout much of the world. Some species, especially ''Laetiporus sulphureus'', are commonly known as sulphur shelf, chicken of the woods, the chicken mushroom, or the chicken fungus becau ...
growing on
yew Yew is a common name given to various species of trees. It is most prominently given to any of various coniferous trees and shrubs in the genus '' Taxus'': * European yew or common yew (''Taxus baccata'') * Pacific yew or western yew ('' Taxus ...
trees.


Poisonous mushrooms

Of the most lethal mushrooms, five—the
death cap ''Amanita phalloides'' ( ), commonly known as the death cap, is a deadly poisonous basidiomycete fungus and mushroom, one of many in the genus ''Amanita''. Originating in Europe but later introduced to other parts of the world since the late ...
(''A. phalloides''), the three
destroying angel The name destroying angel applies to several similar, closely related species of deadly all-white mushrooms in the genus ''Amanita''. They are '' Amanita virosa'' in Europe and '' A. bisporigera'' and '' A. ocreata'' in eastern and western North ...
s (''A. virosa'', ''A. bisporigera'', and ''A. ocreata''), and the fool's mushroom (''A. verna'')—belong to the genus ''
Amanita The genus ''Amanita'' contains about 600 species of agarics, including some of the most toxic known mushrooms found worldwide, as well as some well-regarded Edible mushroom, edible species (and many species of unknown edibility). The genus is re ...
'', and two more—the deadly webcap (''C. rubellus''), and the fool's webcap (''C. orellanus'')—are from the genus ''
Cortinarius ''Cortinarius'' is a globally distributed genus of fungus in the family Cortinariaceae. Its members are commonly known by the names cortinar and webcap. It is suspected to be the largest genus of agarics, containing over 2,000 widespread species ...
''. Several species of
Galerina ''Galerina'' is a genus of small brown-spore saprobic mushroom-bearing fungi, with over 300 species found throughout the world from the far north to remote Macquarie Island in the Southern Ocean. The genus is most noted for some extremely poison ...
,
Lepiota ''Lepiota'' is a genus of gilled mushrooms in the family Agaricaceae. All ''Lepiota'' species are ground-dwelling saprotrophs with a preference for rich, calcareous soils. Basidiocarps (fruit bodies) are agaricoid with whitish spores, typica ...
, and
Conocybe ''Conocybe'' is a genus of mushrooms with '' Conocybe tenera'' as the type species and at least 243 other species. There are at least 50 different species in North America. Most have a long, thin fragile stipe and are delicate, growing in grass ...
also contain lethal amounts of
amatoxin Amatoxins are a subgroup of at least nine related cyclic peptide toxins found in three genera of deadly poisonous mushrooms (''Amanita'', '' Galerina'' and '' Lepiota'') and one species of the genus '' Pholiotina''. Amatoxins are very potent, as li ...
s. Deadly species are listed in the
List of deadly fungi Although many people have a fear of mushroom poisoning by "toadstool A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or another food source. ''Toadstool'' generally ref ...
. The following species may cause great discomfort, sometimes requiring hospitalization, but are not considered deadly. * ''
Amanita muscaria ''Amanita muscaria'', commonly known as the fly agaric or fly amanita, is a basidiomycete fungus of the genus ''Amanita''. It is a large white-lamella (mycology), gilled, white-spotted mushroom typically featuring a bright red cap covered with ...
'' (fly agaric) – Contains the psychoactive
muscimol Muscimol, also known as agarin or pantherine, as well as 5-(aminomethyl)-1,2-oxazol-3-ol, is the principal psychoactive constituent of ''Amanita muscaria'' and '' Amanita pantherina''. Muscimol is an isoxazole alkaloid and a potent and selectiv ...
and the
neurotoxin Neurotoxins are toxins that are destructive to nervous tissue, nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insult (medical), insultsSpencer 2000 that can adversely affect function ...
ibotenic acid Ibotenic acid or (''S'')-2-amino-2-(3-hydroxyisoxazol-5-yl)acetic acid, also referred to as ibotenate, is a naturally occurring alpha-amino acid found in certain ''Amanita'' mushrooms, that primarily acts as a potent glutamate receptor agonist ...
. Ibotenic acid decarboxylates into muscimol upon curing of the mushroom, rendering it relatively non-toxic, though death via
respiratory depression Hypoventilation (also known as respiratory depression) occurs when ventilation is inadequate (''hypo'' meaning "below") to perform needed respiratory gas exchange. By definition it causes an increased concentration of carbon dioxide (hypercapni ...
is possible. Muscimol intoxication is often considered unpleasant and undesirable, however, and as such has seen little recreational use compared to the unrelated
psilocybin mushroom Psilocybin mushrooms, or psilocybin-containing mushrooms, commonly known as magic mushrooms or as shrooms, are a type of hallucinogenic mushroom and a polyphyletic informal group of fungi that contain the prodrug psilocybin, which turns into t ...
, though it has been used as an
entheogen Entheogens are psychoactive substances used in spiritual and religious contexts to induce altered states of consciousness. Hallucinogens such as the psilocybin found in so-called "magic" mushrooms have been used in sacred contexts since ancie ...
by the native people of Siberia. * ''
Amanita pantherina ''Amanita pantherina'', also known as the panther cap, false blusher, and the panther amanita due to its similarity to the true blusher (''Amanita rubescens''), is a species of fungus found in Eurasia with poisonous and psychoactive propertie ...
'' (panther mushroom) – contains similar toxins as ''A. muscaria'', but is associated with more fatalities than ''A. muscaria''. * ''
Chlorophyllum molybdites ''Chlorophyllum molybdites'', commonly known as the green-spored parasol, false parasol, green-spored lepiota and vomiter, is a common species of mushroom found in temperate and subtropical meadows and lawns. The species is poisonous and produ ...
'' (greengills) – causes intense gastrointestinal upset. * ''
Entoloma ''Entoloma'' is a genus of fungi in the order Agaricales. Called pinkgills in English, basidiocarps (fruit bodies) are typically agaricoid (gilled mushrooms), though a minority are gasteroid. All have salmon-pink basidiospores which colour the ...
'' (pinkgills) – some species are highly poisonous, such as livid entoloma ('' E. sinuatum''), '' E. rhodopolium'', and '' E. nidorosum''. Symptoms of intense gastrointestinal upset appear after , 20 minutes to 4 hours, caused by an unidentified gastrointestinal irritant. * Many ''
Inocybe ''Inocybe'' is a genus of mushroom-forming fungi, with over 1,000 species. Its members are mycorrhizal, and some evidence shows that the high degree of speciation is due to adaptation to different trees and possibly also local habitats. Taxonomy ...
'' species such as '' Inocybe fastigiata'' and '' Inocybe geophylla'' contain
muscarine Muscarine, L-(+)-muscarine, or muscarin is a Secondary metabolite, natural product found in certain mushrooms, particularly in ''Inocybe'' and ''Clitocybe'' species, such as the deadly ''Clitocybe dealbata, C. dealbata''. Mushrooms in the g ...
. * '' Inosperma erubescens'' has caused death. * Some white ''
Clitocybe ''Clitocybe'' is a genus of mushrooms characterized by white, off-white, buff, cream, pink, or light-yellow spores, gills running down the stem, and pale white to brown or lilac coloration. They are primarily saprotrophic, decomposing forest grou ...
'' species, including '' C. rivulosa'' and '' C. dealbata'', contain muscarine. * ''
Tricholoma pardinum ''Tricholoma pardinum'', commonly known as spotted tricholoma, tiger tricholoma, tigertop, leopard knight, or dirty trich, is a species of gilled mushroom. First officially described by Christiaan Hendrik Persoon in 1801, it has had a confus ...
'', '' T. tigrinum'' (tiger tricholoma) – gastrointestinal upset due to an unidentified toxin, begins in 15 minutes to 2 hours and lasts 4 to 6 days. * ''
Tricholoma equestre ''Tricholoma equestre'' or ''Tricholoma flavovirens'', commonly known as the man on horseback or yellow knight, is a species of fungus of the genus '' Tricholoma'' that forms ectomycorrhiza with pine trees. It has been treasured as an edible mu ...
'' (man-on-horseback) – until recently thought edible and good, can lead to
rhabdomyolysis Rhabdomyolysis (shortened as rhabdo) is a condition in which damaged skeletal muscle breaks down rapidly. Symptoms may include muscle pains, weakness, vomiting, and confusion. There may be tea-colored urine or an irregular heartbeat. Some o ...
after repeated consumption. * ''
Hypholoma fasciculare ''Hypholoma fasciculare'', commonly known as the sulphur tuft or clustered woodlover, is a common woodland mushroom, often in evidence when hardly any other mushrooms are to be found. This Saprotrophic nutrition, saprotrophic small Lamella (myc ...
''/''Naematoloma fasciculare'' (sulfur tuft) – usually causes gastrointestinal upset, but the toxins fasciculol E and F could lead to paralysis and death. * ''
Paxillus involutus ''Paxillus involutus'', also known as the brown roll-rim or the common roll-rim, is a species of basidiomycete fungus. Although it has lamella (mycology), gills, it is more closely related to the pored boletes than to typical gilled mushroom ...
'' (brown roll-rim) – once thought edible, but now found to destroy
red blood cell Red blood cells (RBCs), referred to as erythrocytes (, with -''cyte'' translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, erythroid cells, and rarely haematids, are the most common type of blood cel ...
s with regular or long-term consumption. * '' Rubroboletus satanas'' (Devil's bolete), '' Suillellus luridus'', ''
Rubroboletus legaliae ''Rubroboletus legaliae'', previously known as ''Boletus splendidus'', ''B. satanoides'', and ''B. legaliae'' is a basidiomycete fungus of the family Boletaceae. It is Mushroom poisoning, poisonous, with predominantly gastrointestinal s ...
'', ''
Chalciporus piperatus ''Chalciporus piperatus'', commonly known as the peppery bolete, is a species of fungus in the family Boletaceae. Described by Jean Baptiste François Pierre Bulliard, Pierre Bulliard in 1790 as ''Boletus piperatus'', it is only distantly rela ...
'', '' Neoboletus luridiformis'', '' Rubroboletus pulcherrimus'' – gastrointestinal irritation. Of these, only ''R. pulcherrimus'' has been implicated in a death. Many books list ''N. luridiformis'' as edible, but Arora lists it as "to be avoided". * ''
Hebeloma crustuliniforme ''Hebeloma crustuliniforme'', commonly known as poison pie or fairy cakes, is a gilled mushroom of the genus ''Hebeloma''. It is found in both the Old and New World and is poisonous. Taxonomy The species' specific name derives from the Latin ...
'' (known as poison pie or fairy cakes) – causes gastrointestinal symptoms such as nausea and vomiting. * ''
Russula emetica ''Russula emetica'', commonly known as the sickener, emetic russula, or vomiting russula, is a basidiomycete mushroom, and the type species of the genus ''Russula''. It was first described in 1774. It has a red, convex to flat pileus (mycology) ...
'' (the sickener) – as its name implies, causes rapid vomiting. Other Russulas with a peppery taste (''
Russula silvicola ''Russula'' is a very large genus composed of around 750 worldwide species of fungi. The genus was described by Christian Hendrik Persoon in 1796. The mushrooms are fairly large, and brightly colored – making them one of the most recognizable ...
'', ''
Russula mairei Formerly ''Russula mairei'' (Singer), and commonly known as the beechwood sickener, the now re-classified fungus ''Russula nobilis'' (Velen.) is a basidiomycete mushroom of the genus ''Russula''. This group of mushrooms are noted for their brit ...
'') will likely do the same. * '' Agaricus hondensis'', ''
Agaricus californicus ''Agaricus californicus'', commonly known as the mock meadow mushroom, or California agaricus, is a species of fungus in the section (biology), section ''Xanthodermati'' of the genus ''Agaricus''. The mushroom is mildly mushroom poisoning, pois ...
'', '' Agaricus praeclaresquamosus'', ''
Agaricus xanthodermus ''Agaricus xanthodermus'', commonly known as the yellow-staining agaricus, yellow-staining mushroom or yellow-stainer, is a species of fungus in the genus ''Agaricus''. It displays a strong yellow colouration at the base of the stem when cut. It ...
'' – cause vomiting and diarrhea in most people, although some people seem to be immune. * ''
Lactifluus piperatus ''Lactifluus piperatus'' (synonym ''Lactarius piperatus''), commonly known as the blancaccio, is a basidiomycete fungus of the genus '' Lactifluus''. It was the original type species of the genus ''Lactarius'', before being moved to ''Lactifluus ...
'', ''
Lactarius torminosus ''Lactarius torminosus'', commonly known as the woolly milkcap or the bearded milkcap, is a large species of agaric fungus. It was first described scientifically by Jacob Christian Schäffer in 1774 as an ''Agaricus'', and later transferred to t ...
'', '' Lactarius rufus'' – these and other peppery-tasting milk-caps are pickled and eaten in
Scandinavia Scandinavia is a subregion#Europe, subregion of northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. ''Scandinavia'' most commonly refers to Denmark, Norway, and Sweden. It can sometimes also ...
, but are indigestible or poisonous unless correctly prepared. * '' Lactarius vinaceorufescens'', '' Lactarius uvidus'' – reported to be poisonous. Arora reports that all yellow- or purple-staining ''Lactarius'' are "best avoided". * '' Ramaria gelatinosa'' – causes indigestion in many people, although some seem immune. * '' Gomphus floccosus'' (the scaly chanterelle) – causes gastric upset in many people, although some eat it without problems. ''G. floccosus'' is sometimes confused with the chanterelle.


Evolution

Many different species of mushrooms are poisonous and contain differing
toxins A toxin is a naturally occurring poison produced by metabolic activities of living cells or organisms. They occur especially as proteins, often conjugated. The term was first used by organic chemist Ludwig Brieger (1849–1919), derived ...
that cause different types of harm. The most common toxin that causes severe poisoning is
amatoxin Amatoxins are a subgroup of at least nine related cyclic peptide toxins found in three genera of deadly poisonous mushrooms (''Amanita'', '' Galerina'' and '' Lepiota'') and one species of the genus '' Pholiotina''. Amatoxins are very potent, as li ...
, found in various mushroom species that cause the most fatalities every year.
Amanita The genus ''Amanita'' contains about 600 species of agarics, including some of the most toxic known mushrooms found worldwide, as well as some well-regarded Edible mushroom, edible species (and many species of unknown edibility). The genus is re ...
, or “ the death cap”, is a type of mushroom named for its substantial amount of amatoxin, which has about 10 mg per mushroom, which is the lethal dose. Amatoxin blocks the replication of DNA, which leads to cell death. This can affect cells that replicate frequently, such as
kidneys In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and right in the retro ...
,
livers The liver is a major metabolic organ exclusively found in vertebrates, which performs many essential biological functions such as detoxification of the organism, and the synthesis of various proteins and various other biochemicals necessary for ...
, and eventually, the
central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain, spinal cord and retina. The CNS is so named because the brain integrates the received information and coordinates and influences the activity o ...
. It can also cause the loss of muscle contraction and liver failure. Despite the severe and dangerous symptoms, amatoxin poisoning is treatable given quick, professional care. Mushrooms have also been found to have evolved toxicity independently from each other. Researchers have found that different mushroom species share the same type of amatoxin called amanitin. They specifically looked at three of the deadliest species,
Amanita The genus ''Amanita'' contains about 600 species of agarics, including some of the most toxic known mushrooms found worldwide, as well as some well-regarded Edible mushroom, edible species (and many species of unknown edibility). The genus is re ...
,
Galerina ''Galerina'' is a genus of small brown-spore saprobic mushroom-bearing fungi, with over 300 species found throughout the world from the far north to remote Macquarie Island in the Southern Ocean. The genus is most noted for some extremely poison ...
, and
Lepiota ''Lepiota'' is a genus of gilled mushrooms in the family Agaricaceae. All ''Lepiota'' species are ground-dwelling saprotrophs with a preference for rich, calcareous soils. Basidiocarps (fruit bodies) are agaricoid with whitish spores, typica ...
. Through
genome sequencing Whole genome sequencing (WGS), also known as full genome sequencing or just genome sequencing, is the process of determining the entirety of the DNA sequence of an organism's genome at a single time. This entails sequencing all of an organism's ...
, a scientific process that determines the DNA sequence of an organism’s genome, closely related mushrooms obtained genetic information via
horizontal gene transfer Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between organisms other than by the ("vertical") transmission of DNA from parent to offspring (reproduction). HGT is an important factor in the e ...
. Once assimilated, it can then be passed down to an offspring. The researchers also concluded that there is “an unknown ancestral fungal donor,” that allowed for horizontal gene transfer. Mushroom toxins have appeared and disappeared many times throughout their evolutionary history. Many scientists believe that the toxins evolved in mushrooms are used to deter predation, either from
fungivores Fungivory or mycophagy is the process of organisms consuming fungi. Many different organisms have been recorded to gain their energy from consuming fungi, including birds, mammals, insects, plants, amoebas, gastropods, nematodes, bacteria and othe ...
or mammals. If mushrooms are consumed, it can negatively affect their ability to disperse
spores In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plant ...
, survive, and reproduce. Snails and insects are fungivores and many have learned or evolved to avoid eating poisonous mushrooms. However, it is believed that mammals pose a higher threat to mushrooms than fungivores, as larger body sizes mean they are more capable of eating an entire fungus in one sitting. Some
phenotypes In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological properti ...
, or observable characteristics, may co-occur with toxicity, and therefore act as a warning signal. The first potential warning sign is
aposematism Aposematism is the Advertising in biology, advertising by an animal, whether terrestrial or marine, to potential predation, predators that it is not worth attacking or eating. This unprofitability may consist of any defenses which make the pr ...
, which is an adaptation that warns off predators based on a physical trait of an organism. In this case, the researchers were interested in observing whether the color of a mushroom deters predators. This would suggest that toxic mushrooms are of different colors than non-poisonous ones. The visual cue of some colors should be enough for predators to know not to consume the mushroom. The second possible warning sign is
olfactory The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it ...
aposematism, a similar concept, but instead of focusing on color, the odor of the mushroom would be what deters predation. This would again indicate that poisonous mushrooms would emit a different odor than non-poisonous ones. Alternatively, is the ability of organisms to learn from other organisms. This would suggest that avoidance of toxic mushrooms is a learned behavior. Organisms may avoid toxic mushrooms if they observed other organisms of the same species consume the fungus. Learned behavior is when an organism learns how to behave based on previous experiences. Some researchers believe that if an organism got sick or observed another organism get sick from consuming a poisonous mushroom, then they would know not to continue consuming it for fear of getting sick again. An analysis of 245 North American mushroom species and 265 from Europe, revealed 21.2% of the North American species and 12.1% of the European ones as poisonous. After collecting this information, and using a neural network to classify all of the mushrooms based on color and odor, the researchers concluded that there was no correlation between
cap A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. The origin of the word "cap" comes from the Old French word "chapeau" which means "head co ...
color and mushrooms containing toxins. The cap is the top, rounded part of a mushroom and comes in different colors. This proposes that the cap color does not act as a warning sign to deter predators, providing no evidence that poisonous mushrooms may not signal their toxicity through visual or chemical traits. The three deadly mushrooms listed above, Amanita, Galerina, and Lepiota, are all of different colors, consisting of reds, yellows, browns, and whites. A possible theory as to why color is not a factor in determining whether a mushroom is poisonous is the fact that many of its predators are
nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...
and have poor vision. Therefore, viewing the different colors is difficult, and could result in inaccurate consumption. The study, however, did suggest that poisonous mushrooms do emit a smell that is unpleasant and therefore discourages consumption. Despite this result, there is no definitive evidence to suggest if the odor is a result of the production of the toxin or if it is intended as a warning signal. Additionally, many of the odors are not picked up by humans. This could suggest that there is another characteristic difference between poisonous and non-poisonous mushrooms to avoid predation from larger mammals or that there is another purpose for some mushrooms being poisonous that is not dependent on predators.


Prognosis and treatment

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 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 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. In the United States, mushroom poisoning kills an average of about 3 people a year. According to National Poison Data System (NPDS) annual reports published by America's Poison Centers, the average number of deaths occurring over a ten-year period (2012–2020) sits right at 3 a year. In 2012, 4 out of the 7 total deaths that occurred that year, were attributed to a single event where a "housekeeper at a Board and Care Home for elderly dementia patients collected and cooked wild (Amanita) mushrooms into a sauce that she consumed with six residents of the home.". Over 1,300 emergency room visits in the United States were attributed to poisonous mushroom ingestion in 2016, with about 9% of patients experiencing a serious adverse outcome.


Society and culture


Folklore

Many old wives' tales concern the defining features of poisonous mushrooms. However, there are no general identifiers for poisonous mushrooms, so such beliefs are unreliable. Guidelines to identify particular mushrooms exist, and will serve only if one knows which mushrooms are toxic. Examples of erroneous folklore "rules" include: * "Poisonous mushrooms are brightly colored." – Indeed,
fly agaric ''Amanita muscaria'', commonly known as the fly agaric or fly amanita, is a basidiomycete fungus of the genus ''Amanita''. It is a large white- gilled, white-spotted mushroom typically featuring a bright red cap covered with distinctive white ...
, usually bright-red to orange or yellow, is narcotic and hallucinogenic, although no human deaths have been reported. The deadly
destroying angel The name destroying angel applies to several similar, closely related species of deadly all-white mushrooms in the genus ''Amanita''. They are '' Amanita virosa'' in Europe and '' A. bisporigera'' and '' A. ocreata'' in eastern and western North ...
, in contrast, is an unremarkable white. The deadly ''
Galerina ''Galerina'' is a genus of small brown-spore saprobic mushroom-bearing fungi, with over 300 species found throughout the world from the far north to remote Macquarie Island in the Southern Ocean. The genus is most noted for some extremely poison ...
s'' are brown. Some choice edible species ( chanterelles, ''
Amanita caesarea ''Amanita caesarea'', commonly known as Caesar's mushroom, is a highly regarded edible mushroom in the genus ''Amanita'', native to southern Europe and North Africa. While it was first species description, described by Giovanni Antonio Scopol ...
'', ''
Laetiporus sulphureus ''Laetiporus sulphureus'' is a species of bracket fungus (fungi that grow on trees). Its common names include sulphur polypore, sulphur shelf, and chicken-of-the-woods. Its fruit bodies grow as striking golden-yellow shelf-like structures on tre ...
'', etc.) are brightly colored, whereas most poisonous species are brown or white. * "Insects/animals will avoid toxic mushrooms." – Fungi that are harmless to invertebrates can still be toxic to humans; the
death cap ''Amanita phalloides'' ( ), commonly known as the death cap, is a deadly poisonous basidiomycete fungus and mushroom, one of many in the genus ''Amanita''. Originating in Europe but later introduced to other parts of the world since the late ...
, for instance, is often infested by insect
larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...
e. * "Poisonous mushrooms blacken
silver Silver is a chemical element; it has Symbol (chemistry), symbol Ag () and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. ...
." – None of the known mushroom toxins react with silver. * "Poisonous mushrooms taste bad." – People who have eaten the deadly ''
Amanita The genus ''Amanita'' contains about 600 species of agarics, including some of the most toxic known mushrooms found worldwide, as well as some well-regarded Edible mushroom, edible species (and many species of unknown edibility). The genus is re ...
s'' and survived have reported that the mushrooms tasted quite good. * "All mushrooms are safe if cooked/parboiled/dried/pickled/etc." – While it is true that some otherwise-inedible species can be rendered safe by special preparation, many toxic species cannot be made toxin-free. Many fungal toxins are not particularly sensitive to heat and so are not broken down during cooking; in particular,
α-Amanitin α-Amanitin (''alpha''-Amanitin) is a cyclic peptide of eight amino acids. It is possibly the most deadly of all the amatoxins, toxins found in several species of the mushroom genus ''Amanita'', one being the death cap (''Amanita phalloides'') as ...
, the poison produced by the death cap (''
Amanita phalloides ''Amanita phalloides'' ( ), commonly known as the death cap, is a deadly poisonous basidiomycete fungus and mushroom, one of many in the genus ''Amanita''. Originating in Europe but later introduced to other parts of the world since the late ...
'') and others of the
genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
, is not denatured by heat. * "Poisonous mushrooms will turn rice red when boiled." – A number of Laotian refugees were hospitalized after eating mushrooms (probably toxic ''
Russula ''Russula'' is a very large genus composed of around 750 worldwide species of fungi. The genus was described by Christian Hendrik Persoon in 1796. The mushrooms are fairly large, and brightly colored – making them one of the most recognizable ...
'' species) deemed safe by this folklore rule and this misconception cost at least one person her life. * "Poisonous mushrooms have a pointed cap. Edible ones have a flat, rounded cap." – The shape of the mushroom cap does not correlate with presence or absence of mushroom toxins, so this is not a reliable method to distinguish between edible and poisonous species.
Death cap ''Amanita phalloides'' ( ), commonly known as the death cap, is a deadly poisonous basidiomycete fungus and mushroom, one of many in the genus ''Amanita''. Originating in Europe but later introduced to other parts of the world since the late ...
, for instance, has a rounded cap when mature. * "
Boletes A bolete is a type of mushroom, or fungal fruiting body. It can be identified thanks to a unique cap. On the underside of the cap there is usually a spongy surface with pores, instead of the gills typical of mushrooms. A similar pore surface is ...
are, in general, safe to eat." – It is true that, unlike a number of ''Amanita'' species in particular, in most parts of the world, there are no known deadly varieties of the genus ''Boletus'', which reduces the risks associated with misidentification. However, mushrooms like the Devil's bolete are poisonous both raw and cooked and can lead to strong gastrointestinal symptoms, and other species like the
lurid bolete ''Suillellus luridus'' (formerly ''Boletus luridus''), commonly known as the lurid bolete, is a fungus of the family Boletaceae, found in calcareous broad-leaved tree, broadleaved woodlands in Europe. Basidiocarp, Fruit bodies appear in summer ...
require thorough cooking to break down toxins. As with another mushroom ''genera'', proper caution is, therefore, advised in determining the correct species.


Notable cases

*
Siddhartha Gautama Siddhartha Gautama, most commonly referred to as the Buddha (),* * * was a śramaṇa, wandering ascetic and religious teacher who lived in South Asia during the 6th or 5th century BCE and founded Buddhism. According to Buddhist lege ...
(known as The Buddha), by some accounts, may have died of mushroom poisoning around ~479 BCE, though this claim has not been universally accepted. * Roman Emperor
Claudius Tiberius Claudius Caesar Augustus Germanicus ( ; ; 1 August 10 BC – 13 October AD 54), or Claudius, was a Roman emperor, ruling from AD 41 to 54. A member of the Julio-Claudian dynasty, Claudius was born to Nero Claudius Drusus, Drusus and Ant ...
is said to have been murdered by being fed the
death cap ''Amanita phalloides'' ( ), commonly known as the death cap, is a deadly poisonous basidiomycete fungus and mushroom, one of many in the genus ''Amanita''. Originating in Europe but later introduced to other parts of the world since the late ...
mushroom. However, this story first appeared some two centuries after the events, and it is debatable whether Claudius was murdered at all. * The best-selling author
Nicholas Evans Nicholas Benbow Evans (26 July 1950 – 9 August 2022) was a British journalist, screenwriter, television and film producer and novelist. He was best known for his 1995 debut novel, ''The Horse Whisperer (novel), The Horse Whisperer''. It has s ...
('' The Horse Whisperer'') was poisoned (but survived) after eating ''
Cortinarius rubellus ''Cortinarius rubellus'', commonly known as the deadly webcap, is a species of fungus in the family Cortinariaceae, native to high-latitude temperate to subalpine forests of Eurasia and North America. Within the genus it belongs to a group know ...
''. * The parents of the physicist
Daniel Gabriel Fahrenheit Daniel Gabriel Fahrenheit FRS (; ; 24 May 1686 – 16 September 1736) was a physicist, inventor, and scientific instrument maker, born in Poland to a family of German extraction. Fahrenheit invented thermometers accurate and consistent enough t ...
, who created the
Fahrenheit The Fahrenheit scale () is a scale of temperature, temperature scale based on one proposed in 1724 by the German-Polish physicist Daniel Gabriel Fahrenheit (1686–1736). It uses the degree Fahrenheit (symbol: °F) as the unit. Several accou ...
temperature scale, died in Danzig on 14 August 1701 from accidentally eating poisonous mushrooms. * The composer Johann Schobert died in Paris, along with his wife, all but one of his children, their maidservant, and four acquaintances after insisting that certain poisonous mushrooms they had gathered were edible despite the express warning of cooks at two separate restaurants to which he had taken the mushrooms. * July 2023 Leongatha mushroom poisoning − Four people in
Leongatha Leongatha () is a town in the foothills of the Strzelecki Ranges, South Gippsland Shire, Victoria (Australia), Victoria, Australia, located south-east of Melbourne. At the , Leongatha had a population of 5,869. Canadian dairy company Saputo In ...
,
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
were taken to hospital after consuming
beef Wellington Beef Wellington is a baked steak dish of English origin, made out of fillet steak and duxelles wrapped in shortcrust pastry. Some recipes include wrapping the contents in prosciutto, or dry-cured ham, which helps retain moisture while preve ...
suspected to have contained
death cap ''Amanita phalloides'' ( ), commonly known as the death cap, is a deadly poisonous basidiomycete fungus and mushroom, one of many in the genus ''Amanita''. Originating in Europe but later introduced to other parts of the world since the late ...
mushrooms. Three of the four guests subsequently died and one survived, later receiving a
liver transplant Liver transplantation or hepatic transplantation is the replacement of a Liver disease, diseased liver with the healthy liver from another person (allograft). Liver transplantation is a treatment option for Cirrhosis, end-stage liver disease and ...
. The woman who cooked the meal, Erin Patterson, was charged with murder in November 2023. Patterson has pleaded not guilty and the Supreme Court of Victoria is expected to hear her case on 28 April, 2025. * In August 2023, Professor Vitaly Melnikov, 77, who had headed the
Moscow Moscow is the Capital city, capital and List of cities and towns in Russia by population, largest city of Russia, standing on the Moskva (river), Moskva River in Central Russia. It has a population estimated at over 13 million residents with ...
Department of Rocket and Space Systems at RSC Energia (Russia's leading spacecraft manufacturer), became suddenly seriously ill and subsequently died after eating inedible mushrooms.


See also

*
List of deadly fungi Although many people have a fear of mushroom poisoning by "toadstool A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or another food source. ''Toadstool'' generally ref ...
(for lethal species only) * List of poisonous fungi (including non-deadly species that are nevertheless harmful)


References


External links


Poisonous American Mushrooms – AmericanMushrooms.com


from medical mycologist R.C. Summerbell

from the
North American Mycological Association The North American Mycological Association (NAMA), is a non-profit organization of amateurs and professionals who are interested in fungi, including mushrooms, morels, truffles, molds, and related organisms. NAMA aims "to promote, pursue, and advan ...

Mushroom Poisoning Case Registry
(North America) from the
North American Mycological Association The North American Mycological Association (NAMA), is a non-profit organization of amateurs and professionals who are interested in fungi, including mushrooms, morels, truffles, molds, and related organisms. NAMA aims "to promote, pursue, and advan ...

American Association of Poison Control Centers
Provides information on the toxicity of mushrooms in your area, symptoms and first aid. * {{Authority control Mycotoxins Toxic effect of noxious substances eaten as food