Death Cap: The Deadliest Mushroom in the World

Every part of a death cap is poisonous, even its name. To make both forest walks and foraging safer, every forest lover should learn how to recognize it and know the symptoms of death cap poisoning.

WHY IT IS THE DEADLIEST MUSHROOM

The death cap is one of the most poisonous mushrooms out there and it poisons more people than all other mushrooms combined. Indeed, despite the death cap (Amanita phalloides) is easy to recognize, but hundreds of foragers poison themselves and their families each year. Let’s examine how to avoid that fate.

HOW TO RECOGNIZE A DEATH CAP

A death cap is 2-5 inches wide and 4-6 inches tall. It has an olive-green cap with a smooth rim, dense white gills free of the stalk, sometimes with remains of a veil, and a stalk with a striated ring and a bulbous base with a prominent volva. The smell is sweet with a hint of raw potatoes.

A young death cap is round and covered with a white veil. In this stage, it literally looks like an egg. The remains of this veil at the base of the mushroom become the volva. Sometimes, a piece of this veil can remain on the cap to become a wart.

The cap is hemispherical at first and opens with age to become almost flat.

The spore print is white. The spores are elliptic and short.

WHERE ARE DEATH CAPS FOUND?

Death caps naturally occur during summer and autumn in the deciduous forests of warm parts of Europe, Asia, and North Africa. Humanity accidentally introduced them to North America and Australia, where they are spreading fast.

The fact that they are so widespread means that everyone in the world should learn about them. And I don’t mean just foragers. To know that a mushroom is deadly will allow you to act if your kid or dog accidentally eats one. And to know how to perform first aid (which mostly means calling an ambulance).

The death cap isn’t killing people by itself. It partners with ignorance to do it.

TREES THAT DEATH CAPS GROW UNDER

Death caps mostly grow in symbiosis with deciduous trees like oak, beech, and hornbeam, but you can also find them under pine and spruce. A death cap needs to form a relationship with a tree and can’t grow alone.

The tree provides the mushroom with organic molecules that it produces in photosynthesis. In return, the death cap provides the tree with water and minerals that it absorbs from the soil. This kind of symbiosis is called mycorrhiza.

A “hatching” egg, now 100% death cap

WHAT MAKES THE DEATH CAP MUSHROOM SO DEADLY

Death caps are responsible for 90% of mushroom-related deaths worldwide because they are mismatched for popular edible mushroom species. They contain deadly toxins with delayed effects, which complicates first aid. A single mushroom can kill a human.

CAN YOU SURVIVE EATING A DEATH CAP?

The death rate of death cap poisoning is 50% if untreated and about 13% if treated. It decreases each year as new research allows to improve treatment. An individual’s survival depends on the amount of mushroom consumed and the speed of diagnosis and medical aid quality.

That’s why, in case of death cap poisoning, you need to call the ambulance immediately.

CAN YOU DIE FROM TOUCHING A DEATH CAP?

Touching a death cap cannot poison you. The toxins are contained inside the flesh of the mushroom and can’t be absorbed through your skin.

This knowledge is quite important for a mushroom forager. Touching mushrooms, turning them over, smelling them, and studying them is essential for identifying and learning new species.

Of course, some scruples towards touching a poisonous mushroom are natural. Parents may choose to confuse their kids about this to keep them safe. Mine did. I remember that because of that, as a nine-year-old, I treated even the picture of a death cap in our family mushroom guide book with tremendous respect.

CAN YOU DIE FROM LICKING A DEATH CAP?

Licking a death cap wouldn’t kill you. You would have to eat a piece of the mushroom to poison yourself. Despite that, licking poisonous mushrooms is not a practice to be encouraged.

ARE DEATH CAP SPORES DANGEROUS?

The spores of a death cap are highly toxic.  Avoid consuming them. If you forage a death cap for some reason (to make a spore print etc.), keep it separately from edible mushrooms to avoid contaminating them.

DANGEROUS MYTHS

Alongside misidentification, myths are a second major reason why people poison themselves with the death cap. There are many false claims about death caps and poisonous mushrooms out there that aren’t true. Let me debunk a few of them for you now.

1. Contrary to common belief, death caps are actually delicious. Not bitter, not hot. Hundreds of people who ate them confirm this.
2. Heat preparation doesn’t destroy the death cap’s poison. Most people who poison themselves with a death cap cook it. While there are some thermo-labile toxins in the death cap, its deadliest toxins are very stable.
3. The flesh of a death cap doesn’t change color when bruised.
4. Milk is not an antidote to death cap toxins (nor for any other mushroom poison). There is no antidote to the death cap’s poisons.
5. Silver doesn’t change color after contact with the poison.
6. The fact that animals munched on a mushroom doesn’t mean that the mushroom is edible to humans. Squirrels, insects, or slugs have a different metabolism than we do, and death cap toxins don’t harm them.

If you know other myths about death cap identification or first aid, please let me know in the comments. I want to add that to this list to make it more helpful.

Squirrels’ metabolism allows them to eat death caps.

WHAT HAPPENS IF A HUMAN ACCIDENTALLY EATS A DEATH CAP MUSHROOM

The death cap’s toxins quickly leave the digestive system and start attacking liver cells. The symptoms appear 8-24 hours later. Then, either the victim dies of dehydration or the symptoms recede. In that case, the victim will then often die of kidney or liver failure 4-12 days from the poisoning.

Let’s look at it more thoroughly now.

PRE-SYMPTOMATIC

After consumption of a death cap, the first stage of the poisoning starts almost immediately. The toxins are absorbed from the digestive system into the blood flow and begin attacking hepatocytes (liver cells). The symptoms of the poisoning appear only when a lot of these hepatocytes are destroyed.

THE SYMPTOMS

In the first stage, some functions of the digestive system are disrupted. The victim becomes languid, dizzy, and chilly. Then they feel nausea and stomach ache, followed by heavy vomiting and diarrhea. Those lead to dehydration and demineralization. If the victim survives, the vomiting and diarrhea disappear entirely, which may calm the victim – falsely.

2ND STAGE

In the following days, the liver and kidneys will start malfunctioning. The liver enlarges. The victim increasingly urinates, and after about 4 to 5 days from poisoning, they feel better. If they are lucky, they recover. But in most cases, acute failure of the liver or kidneys follows.

In case of a slow progression, the victim dies 8 to 12 days after the poisoning. In the case of a fast progression, liver coma develops quickly, resulting in apathy, loss of consciousness, shaking, spasms, decreased blood pressure, mydriasis, and death 4 to 7 days after the poisoning.

Green is a surprisingly rare color for mushroom caps. Death cap (Amanita phalloides) is one of just a few mushrooms with a green cap.

AMANITIN

The most prominent toxin of death cap is amanitin. To illustrate its deadliness, let me quote the satirical play Afrika:

Aminitin is so poisonous that just the amount that would fit on knife’s tip could kill 100000 mice. You could then line those dead mice in a line 11 miles long that you would march along for an average of 4.5 hours.

Amanitin is the toxin that makes death caps so deadly, the compound that destroys the liver and kidneys. There is no complex antidote for it.

About 50% of the death cap’s amanitin is in the gills, 20% in the cap, 20% in the stalk, and the rest in volva. Spores contain very low if any amanitin but are still highly toxic.

PHALLOTOXINS AND VIROTOXINS

There are other deadly toxins in the death cap. Still, these aren’t responsible for the poisonings. They are either not absorbed from the digestive system or destroyed during heat preparation.

Some thermo-labile phallotoxins that would attack red blood cells are found even in the popular blusher mushroom, which is widely consumed but causes no poisonings.

PIERRE BASTIEN, THE MAN WHO ATE DEATH CAPS ON PURPOSE

In 1974, a 50-year old French doctor Pierre Adrien Bastien decided to experiment on himself and eat a death cap. He based the experiment on the knowledge that some people survive the poisoning and on the (kind of mistaken) assumption that the 1st stage of the poisoning is similar to cholera.

In the presence of a notary, he consumed 50 g (1.5 oz) of a death cap with a piece of bread and a banana. Six hours later, deep into the symptomless 1st stage of poisoning, he went to the resuscitation unit for acute poisonings in Nancy and requested to be treated with the method he designed for this occasion.

His treatment included disinfection of bowels with antibiotics, intravenous administration of vitamin C, and drinking syrup with potassium. It is unknown whether the toxicology unit treated him with anything else.

Dr. Bastien survived, but doctors and journalists contested his experiment because the toxicology unit successfully treated 75% of patients at the time, so that the result could have been just luck. Perhaps that’s why doctor Bastien decided to repeat the experiment in 1976 and presented the public with the results of another successful treatment of himself and 12 other people.

In 1980, he already claimed to have treated 100 people with his method, with a 98% success.

The French public remained skeptical, and so doctor Bastien made one final demonstration in Switzerland. On camera in the cantina of Swiss TV, he ate 70 g (2 oz, about double of the deadly dose) of a death cap sautéed in butter.

Eight hours later, when the first symptoms appeared, he had vitamin C administered intravenously, drank an antibiotic and a bowel disinfectant. This time, he also used treatment to stop vomiting. During treatment, he only ate cooked carrot porridge with yeast.

Once again, he survived, becoming the only person ever to survive death cap poisoning thrice. He finally got the worldwide publicity that he definitely deserved. His experiments permanently damaged his liver, but he lived until 2006 when he died aged 82 of another cause.

It is interesting that animals that cannot make vitamin C from sugars, including humans, are the most sensitive to death cap poisoning. So doctor Bastien may have been onto something. There is still a lot of research ahead of scientists in the decades to come.

THE GÉRARD EXPERIMENT

In 1850, 123 years before Bastien, another Frenchman, M. Gérard, performed a test overseen by a medical council on himself and his family. He pickled death caps in vinegar water for 2 hours, then washed them, cooked them, and ate them along with his family. According to doctor Cadet present at the experiment, the family displayed no symptoms.

The effect of strong acids on amanitin was later tested, with different results. I would discourage anyone from risking the things that Pierre Bastien and the Gérard family have done. But they are, no doubt, heroes of mycology.

FIRST AID FOR DEATH CAP MUSHROOM POISONING

As first aid for death cap poisoning, drink lots of water to avoid dehydration and demineralization and eat activated carbon, which binds the poison to itself. Contact a doctor immediately, even if the symptoms seem to go away. Hospitalization is necessary!

IN THE HOSPITAL

The exact process and chances of recovery depend on the time of diagnosis and the speed of hospitalization. Most cases arrive at the hospital about a day after poisoning. Treatment includes:

1. Special activated carbon that cleans the toxin from blood flow.
2. Repeated or permanent lavage of the digestive tract.
3. Megadoses of penicillin G, which pushes amanitin away from some bonds.
4. Treatment to protect the liver using an extract from blessed milk thistle.
5. Treatment that cleans the poison from the digestive system.

The patients who recover often require a liver or kidney transplant, or both.

HISTORY OF FIRST AID

Historically, death cap poisoning was treated with enema and bloodletting. At the start of the 20th century, the patients drank tea and coffee to stimulate their organism and fight the symptoms.

From the 1920s to the 1970s, patients were treated with a serum made from the blood of horses fed small doses of death caps to make them develop resistance to the poison. The serum didn’t show results, which is not surprising as there is no evidence that the consumption of death caps would cause the organism to develop resistance, nor is there a reason to suspect so.

MISMATCHING

As mismatching is the typical reason why people consume a death cap in the first place, let’s take a look at several mushroom species that are commonly mismatched for one.

PADDY STRAW MUSHROOMS

Straw mushrooms are very similar to death caps and almost identical at a young age. A mismatch is responsible for 90 % of death cap poisonings worldwide.Asian immigrants are typical victims as they come from regions where straw mushrooms are popular and death caps unknown.

Death caps and paddy straws mushrooms are closely related look-alikes. Luckily, they don’t share a habitat.

One way to distinguish the mushroom at a young age is by spore print. Death cap has a white spore print. The straw mushroom has a pink spore print. Another tell is the habitat: death caps are symbiotic with trees, straw mushrooms grow in pre-tillage fields.

CHAMPIGNONS

The death cap’s white variant is almost identical to young champignon mushrooms like the field mushroom or the wood mushroom. The only noticeable difference is the volva, which can be accidentally removed while picking the death cap.

How to tell field mushrooms from an amanita? 1. pink gills, 2. lack of volva, 3. the cap’s rim isn’t smooth.

For this reason, I highly recommend against foraging young champignon mushrooms if their gills haven’t turned pink yet.

GREEN RUSSULAS

Russulas have a white underside with gills, and some of them have a green cap. However, that’s where the similarities go. For an advanced forager, distinguishing them is easy. All it takes is a little experience.

There are 3 major signs to tell a russula from a death cap. 1.Russula mushrooms lack a volva and a ring. 2. Their stem is shorter and cylindrical. 3. The cap is dome-shaped and becomes flatter with time, often with a depression in the middle.

The typical tells of a russula: 1. lack of a ring, 2. lack of a volva, 3. shape of the cap and a depressed middle.

ALBINO BLUSHERS

Blushers are a delicious amanita species closely related to the death cap. Albino versions may be harder to tell from a white death cap. Albino blushers are scarce, and the best approach is not to forage them at all.

CAESAR MUSHROOMS’ EGGS

Caesar’s mushrooms are covered in a veil and resemble an egg just like a young death cap. If you chose to forage these young “eggs,” you need to look for yellow gills on the inside. White gills would signal a death cap or other poisonous amanita species.

Once the veil breaks, it becomes clear that the mushroom isn’t a death cap but a caesar’s mushroom.

PUFFBALLS

Puffballs are popular aromatic mushrooms that are round and white, and cases of mismatching a death cap egg for a puffball sometimes occur. How to tell them apart?

Only minimal experience is required to tell a puffball from an amanita egg.

Puffballs are more elastic, while death cap eggs are tough to the touch. It is easy to recognize the mushroom once you cut it in half. A puffball is full and white inside. An amanita has an apparent cap, stalk, and gills. Therefore, a mismatch could only occur if you cooked the mushroom whole.

POISONOUS LOOK-ALIKES

The destroying angel is a white amanita very similar to the death cap. It has the same toxins and sits with the death cap on the top of the deadliest mushrooms list.

The false death cap has a pale-green cap with remains of the veil. It used to be considered edible but is now proven to contain a mild poison.

False death cap (Amanita citrina)

WHO IS RESPONSIBLE FOR THE IDENTIFICATION?

In case of a mismatch and poisoning, a question of legal responsibility may arise. The person who misidentified and foraged the mushroom will usually be held responsible because typical signs are often removed during cleaning, and others (i.e., the cook) may have relied on the ID provided.

As a forager, play it safe and only harvest mushrooms that you are 100% sure about. As a person further in a chain (a cleaner or a cook), you can check the mushrooms and ask the forager about any suspicious specimens.

HISTORICAL POISONINGS

Death cap was probably the poison of choice of ancient and medieval assassins. It tastes nice and doesn’t kill the victim right away, which allowed the assassins to poison even those victims who employed a taster. The most famous victim of death cap poisoning is Roman Holy Emperor Charles VI.

He died 10 days after consuming sautéed mushrooms. His symptoms were consistent with death cap poisoning. It is unsure whether the meal was made of death caps or if someone added death cap powder to the emperor’s meal.

That mushroom dish changed the destiny of Europe. (Voltaire)

Roman emperor Claudius died after eating his favorite caesar’s mushroom. Authors of that time speculate whether he was poisoned by the mushrooms themselves or whether the poison was added to the meal.

According to Tacitus, the murderer was Claudius’s wife Agrippina, willing to make her son Nero the emperor.

These are the ones that turned my father into a god.

(Nero, eating a mushroom meal)

Russian tsaritsa Natalia Naryshkina consumed pickled mushrooms before her death. In Russia, pickling is a very popular way of preparation. It is unclear whether she died of death cap poisoning or food poisoning as pickling in the wrong way could cause edible mushrooms to develop botulinum toxin and become poisonous.

CONCLUSION

Please exercise maximum caution when foraging species that are similar to the death cap. Dozens of people die each year because of death cap poisoning, and it is quite needless. Careful mushroom foraging is actually very safe.

By sharing this post, you will help spread awareness about death caps and can potentially prevent someone from dying.