To Consume and be damned may be  at your Peril  

In Britain it has long since been assumed that edible mushrooms are those fungi which grow in grassy places, in fields and on grass verges beside country lanes. (1) Horace wrote, “The meadow mushrooms are in kind the best; it is ill trusting any of the rest.”

British laymen who still adhere to this outdated mode of thought, describe their common mushrooms as, white on top, dark underneath. Foreign fruit-bodies are called toadstools, alienated by the response, “I’ll come to your funeral.” To give credit to Horace and his supporters one must put this question, Why risk the temptation of fungal poisoning while there are reliable and easy recognizable edible mushrooms available, which have little or no risk to human health ?

Unbeknown to the British mushroom gatherers however, are the many lookalikes within the genus Agaricus; and to which the shop mushroom is related. Several species may be gathered and added to the same basket, including the Yellow stainer, Agaricus xanthodermus. (2) There has been much emphasis placed on this poisonous species, yet according to the late Dr. Ramsbottom, “It causes sickness, headache and diarrhoea in a small proportion (not more than 10%) of those that eat it; others find it palatable.” This statement represents the diversity found within the wide spectrum of human taste. Having personally sampled this vile tasting fungus, also taking into consideration the blandness of British taste, one might in fact wonder at the above findings.

The word “edible” applied to fungus eating is in fact a common misnomer. It simply implies that a fungus can be eaten, the results of which will be purely a matter of personal taste and can be found in a wide range of delicacies. Consequently the information published in popular field guides will often be contradictory. So what do we have here? A possible disaster-recipe for those untrained in the art of common deception; precisely! For example, Paxillus involutus is a common woodland fungus. Positively dangerous if eaten raw, when cooked it can be fatal if eaten in large quantities and over a prolonged period of time. (3) Yet according to specialised American data, this fungus is rendered harmless depending in which part of the USA it is found. This suggests that the soil can effect the toxicity of a fungus growing in any given locality. The time of year the fungus is gathered and consumed is another factor noted by Americans who use the toxins of various species of Amanita for recreational purposes.

(4) Berkeley’s Outline of British Fungology which was published in 1860, assumed that both Amanita excelsa and Amanita citrina were poisonous, but they had there doubts about the edibility of Amanita pantherina, which at that time they only assumed to be poisonous. Today Amanita excelsa is generally regarded as an edible fungus, but although Amanita citrina is said to be edible by some authorities, it has never the less been proven to contain the toad toxin bufotenin. (5) There are many common fungi which contain mascarine, one of five specific fungal poisons defined by Dr. Rock as a toxin which paralyses the central nervous system.

According to most British authorities Amanita gemmata is a poisonous fungus which contains mascarine. (6) But contrary to this widely held view, Nonis describes this species as “edible and of good quality.” (7) Amanita muscaria the Fly Agaric, has attracted attention for many years. (8) “What little man stands in the forest, perched on one leg and is wrapped in a brilliant red cape ?” In 1869 this fungus was proven to contain only relatively low concentrations of mascarine, and that the majority of this toxin was found in the red cap of this fungus. Later it was discovered that this fungus also contained muscimol and ibotenic acid, the latter toxin was given its technical name by the Japanese. Although the Fly Agaric must be assumed to be poisonous for obvious reasons, it has been eaten on the continent, albeit after par boiling. In fact a local woman says that she has gathered and eaten the Fly Agaric with no side effects what so ever.

Eaten raw Amanita rubescens is a poisonous fungus but its mild toxins are destroyed by cooking. However, this method of destroying toxins is a particularly dangerous venture, especially if the species of fungus is not known. It has been generally assumed that Amanita pantherina contains larger quantities of mascarine than the Fly Agaric, consequently its toxins are preferred for recreational purposes in the USA. (9) However there are many other species of fungi which contain far greater concentrations of muscarine, for example, Inocybe patouillardii contains 500 times more muscarine than the Fly Agaric. A fatal dose is estimated at between 100-150 grammes.

10 Although the toxicity of blue staining species of fungi have been suspected since the Victorian period, in Britain (10) the toxicity of Psilocybe semilanceata, the Liberty cap, was not proven until 1969. (11) A coloured dictionary published in 1982 states that Psilocybe semilanceata is a “poisonous fungus when eaten raw, even fatal if eaten by children but harmless when cooked.” The common Liberty cap is often infused and drank as a herbal tea by English people who use its toxin for recreational purposes. People who take part in this ritual do not consider that the flesh of this fungus to be poisonous, unless of course a large meal is consumed by one person. Fortunately the results will most probably be no more than a severe tummy upset or cramp. The body’s defence mechanism, quickly develops a tolerance against psilocybe, double the quantity of fungus flesh must be consumed to obtain the same effects as the amount first consumed.

There are very few known deadly poisonous species of fungi growing in Britain, but because of its availability in some areas “Amanita phalloides” poses the greatest threat to human life. (12) Together with this funguses many guises, it’s only after a period of latency of between six to thirty six hours this fungus reveals its deadly intent. (13) “Once the toxins enter the bloodstream, they then begin to dissolve the liver.” (14) A dictionary may state that there is a reliable French antidotal serum available on the market, but valuable time may be wasted without adequate medical supervision. After making inquires at Southend hospital’s information centre regarding a possible antidotal serum for Amanita phalloides, a week later I received a telephone call, only to tell me, “We don’t have access to this information.” During the early stages of this illness a recovery has been noted, this however is short lived. There after the victims fight for survival diminishes with every hour that passes them bye. (15) A Woman from Prague mistakenly gathered ten Death caps and made them into an omelette for herself and family, “despite quick hospital treatment” the whole family died within the following two days, the children dying first.

(1)   Findlay. Fungi Folklore, Fiction & Fact. (Kingprint Ltd 1982)

(2) Ramsbottom. Mushrooms and Toadstools. (Collins 1969)

(3) Lincoff G & Mitchel. Toxic and Hallucinogenic Mushroom Poisoning. (Van Nostrand Reinhold Company 1977 )

(4) Berkeley’s British Fungology (London 1860)

(5) Ramsbottom. A Hand Book of Larger Fungi.

(6) Nonis. Mushrooms and Toadstools of Britain and Europe. (David and Charles 1993)
(7) Wasson Gordon R. Ethno Mycological Studies. (Harcourt Brace Jovanovich INC)
(8) First. The Encyclopedia of Pscyoactive Drugs. (Chelsea House Publishing 1966)
(9) Dr. Mirko Svrcek. The Illustrated Book of Mushrooms and Fungi.(Octopus Books 1983)
(10)Occurrence of Psilocybin in the Sporophores of Psilocybe semilanceata.
(Vol 53, p302-4 (BMS 1969)
(11) Dickinson & Lucas. The colour Dictionary of Mushrooms.(Orbis Publishing, London 1982)
(12) Baier J Vancura J. Mushrooms & Toadstools.(Sunburst Books 1995)
(13) Poisonous Mushroom. Alert. http://www.sonnetco.uk./rcollini/misc/poison. htm
(14) Ainsworth & Bisby’s, Dictionary of Fungi. ( C M I 1971 )
(15) Jiri Baier & B vancura, Mushrooms and Toadstools
(Sunburst Books 1995)

© Mr M Gooding. 01.01.2000