Mushroom Toxins.

Edible,Poisonous or Deadly!

Toxins that cause liver damage.

Nova Scotia is home to some fine edible mushrooms,some poisonous ones and also some deadly ones. There is a distinction between poisonous and deadly and it is in this section that I will outline the differences.

The genus Amanita contains some of the deadliest mushroms in Nova Scotia and are responsible for most of the deaths in N.America due to mushroom poisoning.The three white Amanita's namely,Amanita phalloides,A.verna and A.virosa(The Destroying Angel) are closely related species and contain the toxins Amatoxin and Phallotoxin. These toxins have also been found in the genus Lepiota and also Galerina.The toxins attack the liver and are particularly insiduous as the symptoms don't appear for some length of time,usually between 8 and 24 hours after eating. It has been estimated that one fully developed mushroom has the potential to kill two people. The first signs of poisoning are vomiting and diarhhea. These symptoms may last for up to 48 hours. After which these symptoms dissapear and symptoms of liver dysfunction set in. This period is critical for the treatment of the victim. If urgent medical attention is not received the victim succumbs to unconciousness and death usually occurs on the fifth or sixth day.

Muscarine poisoning.

Initially the poison's name was taken from the mushroom that contains the toxin; Amanita muscaria.But it is now known that Ibotenic acid and Muscimol are the primary toxins in A.muscaria and A.pantherina In Nova Scotia we have two varieties of Amanita muscaria. One of which is yellow,Amanita muscaria var formosa which is by far the more common of the two. And we also have Amanita muscaria var muscaria which in my experience is rather rare,being apparently more of a western species.

Yellow-orange Fly Agaric,Amanita muscaria var formosa.

Yellow-orange Fly Agaric, Amanita muscaria var formosa.

Fly Agaric,Amanita muscaria var muscaria.

Fly Agaric, Amanita muscaria var muscaria.

It has been discovered fairly recently that Amanita muscaria (photograph above) and also A.pantherina have only small quantities of the toxin muscarine. On the other hand muscarine was found in large quantities in the genera Inocybe and Clitocybe. Of the genus Inocybe, both I.lacera and I.geophylla contain large amounts of muscarine and both are known to grow in Nova Scotia.

Poisoning due to muscarine sometimes appears while the meal is still being eaten but usually within two hours after ingestion.Symptoms include heavy pespiration,salivation,vomiting and diarrhea.Deaths are known from this type of poisoning.

Ibotenic Acid and Muscimol.

As stated elsewhere above, poisoning's occur primarily from A.muscaria and A.pantherina. The symptoms become apparent as little as thirty minutes after ingestion and can take up to two hours. The rather unpleasant symptoms include delusions,uncontrolled muscular co-ordination,cramps and deep sleep.

Hospitalisation is sometimes required and recovery takes up to 24 hours or longer.

Gyromitrin Poisoning

The Conifer False Morel,Gyromitra esculenta,photographs at left, is one of our Spring mushrooms. There has been a lot written about this particular mushroom as regards it's edibility. It should be treated as DEADLY. For a long time it was thought that the toxin involved was Helvellic acid. This has since been discounted and the toxin that was isolated was named gyromitrin which quickly metabolises in to the very poisonous monomethylhydrazine.

Symptoms do not usually occur until six to twelve hours after ingestion. The symptoms include,diarrhea, a bloated feeling,dizziness and loss of coordination. In severe cases death can occur, which is preceded by convulsions and coma.

Psilocybin and Psilocin poisoning.

There are several genera which contain Psilocybin amd Psilocyn. Psilocybe,which is probably the best known of them all, is common in Nova Scotia and could be categorised as an L.B.M ,(Little Brown Mushroom) all little brown mushrooms are difficult to tell apart,even for an expert. The mushrooms containing these toxins are known for their hallucinogenic effects and are considered poisonous. The amount of toxin varies widely from species to species, and as previously stated they are difficult to tell apart.Other genera known to contain these toxins are Stropharia,Gymnopilus,Conocybe and Panaeolina (formerly Psathyrella).

Symptoms usually appear within an hour of ingestion and can have extreme variations.Some people experience euphoria,others fear or anxiety. Sight disorders,visions and delusions are common. The combination of some of these effects may lead to delirium and suicide attempts.

Orellanin Poisoning caused by the genus Cortinarius.

The toxin Orellanin takes it's name from Cortinarius orellanus. The first poisoning being attributed to it in Poland in the early 1960's. As far as I am aware C.orellanus does not grow in Nova Scotia. Unfortunately this is cold comfort. Cortinarius is a large genus containing up to 800 species in North America with only about half of them being described.It is estimated there are between 200-300 species in Nova Scotia. Since the first poisoning with C.orellanus many Cortinarius species have been found to contain this toxin. It also follows that as more species are described and their"attributes" recognised, the list of poisonous species within this genus will undoubtably increase. Some field guides list various species of Cortinarius as edible and some field guides come down on the side of caution and say that you should not consume any species that belong to this genus. Since there are a lot of look-alikes within this genus I believe that it is always best to err on the side of caution. Personally I would not eat any species from this genus.

Symptoms of Orellanin poisoning usually take quite some time to manifest themselves and it may take up to two weeks or longer before the victim feels unwell.It follows that the victim doesn't usually make the connection between the ingestion of the mushrooms and the onset of symptoms.Orellanin poisoning affects the kidneys and can cause kidney failure. Some of the symptoms include an over production of urine, at first, which slows down and ultimately stops altogether. Death occurs from renal failure.

Shown below are two members of the Cortinarius genus. C.semisanguineus shows the cobwebby remnants of the veil,the cortina.The cortina is much easier to see in immature specimens (before the cap has expanded). While C.alboviolaceus shows the cortina around the stalk after the cap has fully expanded.

Silvery Violet Cort, Cortinarius alboviolaceus.

Poisoning of the immune system by Paxillus involutus.

For many years people in Eastern and Central Europe ate this mushroom with apparent impunity. It was not until the late 1940's that it's edibility was brought in to question. It is now known that people who have eaten this mushroom for many years develop an allergic reaction to it and it attacks red blood cells resulting in kidney failure. This is a common mushroom in Nova Scotia and obviously should not be eaten.

Mushrooms containing various unknown toxins

Because of the various toxins involved,the amount ingested and the general health of the victim it is difficult to be precise about the various symptoms involved. However,in general the symptoms will include nausea,diarrhea,vomiting and abdominal pain. Recovery may be within a few hours or a few days depending on the circumstances outlined above.The mushrooms photographed below are some of the many mushrooms that have unknown toxins contained in them. These are but a representative portion of the more common toxic mushrooms that grow in Nova Scotia.