Death cap mushrooms: why are they so toxic and how can poisoning be treated? | Fungi

2023-08-11 23:25:02

Death cap mushrooms: why are they so toxic and how can poisoning be treated? | Fungi

Three people are dead and one is in a critical condition in a Melbourne hospital from suspected mushroom poisoning after eating a beef wellington pie in the Victorian town of Leongatha.

Police have said their symptoms were consistent with having eaten death cap mushrooms, although the official cause of death has not yet been confirmed.

Carrickfergus crash: Tributes paid as police name girl who died following crash in Co Antrim as Scarlett Rosborough (8)

The death cap, Amanita phalloides, is responsible for about 90% of mushroom-related deaths globally. It can be mistaken for edible mushroom varieties such as the field mushroom or the straw mushroom.

“It’s quite upright, it’s very bright white … it’s eye-catching,” says Dr Michael Taylor, a mycology expert at Flinders University.

The cap of a typical Amanita phalloides mushroom may measure about 10cm across, Taylor says. “Half of that would be toxic, probably enough to kill a person. That might be, once it’s cooked down, a mouthful – maybe two or three mouthfuls of actual mushroom … at absolute most.”

Fresh Strikes At Gatwick Threaten Holiday Plans Of 45,000 Passengers

The toxicity of individual mushrooms may vary depending on geographical location, Taylor says. Death caps are not native to Australia and are usually only found in Victoria and the Australian Capital Territory.

What are the effects of eating a death cap mushroom?

“Death cap mushrooms contain three broad classes of toxins: the amatoxins, the phallotoxins and the virotoxins,” says Dr Ian Musgrave, a molecular pharmacologist at the University of Adelaide.

The most toxic of these is an amatoxin known as α-Amanitin. Amatoxins inhibit an enzyme called RNA polymerase II, preventing cells from carrying out essential functions such as creating proteins. The toxin cannot be destroyed by cooking or drying.

Robbie Robertson: The Band's Guitarist and Songwriter Passes Away at 80

Once a death cap is eaten, people are often asymptomatic for several hours before its effects become apparent. Nausea, diarrhoea and other symptoms of gastrointestinal upset develop from about six to 12 hours after ingestion, though this may occur sooner if a high dose is ingested, Taylor says.

The primary site of α-Amanitin toxicity is the liver, where it first travels after being absorbed from the lining of the gastrointestinal tract. “It’ll stop the liver functioning and then after a period of time, the liver will die,” Taylor says.

The toxin has the same effect on all the cells it interacts with.

Taylor Swift's Eras Tour Broke These Five Records So Far

“Quite often you have … a period of remission in which you stop being immediately sick, the nausea calms down, you start feeling pretty well again,” Taylor says. “Then you hit that 24-hour-plus mark if you’ve had a relatively low dose. That’s when you start to get the secondary toxic effects … the liver and other organs start to shut down.”

Within one to seven days of ingestion, the death cap can result in liver failure, kidney failure, encephalopathy, and death.

How is death cap poisoning treated?

Antidotes to α-Amanitin are “mostly not very good”, Musgrave says. “The binding of the amatoxin to its target is largely irreversible – it’s very hard to get around it.”

FBI agent lied about knowledge of Hunter Biden laptop, talks with Facebook

A compound called silibinin can be used to treat death cap poisoning. It works by competitively binding to the same receptors in the liver that α-Amanitin binds to.

But it is only effective if administered before the toxin starts to irreversibly bind to cells – which may be before a person begins to show symptoms, depending on the dose.

“The quicker that you are administered it, the far better is the prognosis,” Taylor

If you would like to know other articles similar to Death cap mushrooms: why are they so toxic and how can poisoning be treated? | Fungi updated this year 2024 you can visit the category UK News.