It's a trap: Deathcap mushroom warning as wet weather arrives in Australia

Wild mushrooms are 'mushrooming' around Australia this Autumn after wet weather, prompting the Food Safety Information Council to warn people about being extremely careful around wild mushrooms because of the deadly, deathcap mushroom poisoning risk.

The poison in the quarter of a cap of one deathcap mushroom, if eaten, is enough to kill a healthy adult. The toxin in deathcap mushrooms is not destroyed by peeling, cooking or drying.

Council chair Cathy Moir said deathcap mushrooms can appear at any time of year but are more common a week or two after good rains. They have been found in the Canberra region, in and around Melbourne, in Tasmania and in Adelaide growing in warm wet weather. They are not native to Australia and are often found near English oak trees.

The similar native marbled deathcap mushrooms have been found in Western Australia, although they may not be as toxic. While no cases have been reported in other states, it is possible that they also grow there.

She said deathcap mushrooms are difficult to distinguish from other wild mushrooms, so advised it is best to only eat mushrooms bought from a supermarket, greengrocer or other reputable source.

Cathy said foraging for wild food is becoming a popular activity, and is strongly promoted by influencers on social and conventional media.

'We are particularly concerned about this growing online promotion of mushroom foraging with some wild mushroom social media groups having over 40,000 members seeking to have their photos of mushrooms identified by fellow foragers," she said.

"Apps and Google are not reliable to identify mushrooms accurately as they often only recognise Northern Hemisphere mushrooms and mushrooms change appearance during their growth cycle."

For people born outside of Australia, particularly from European and Asian countries, Cathy wanted to let them know that deadly mushrooms look like the mushrooms they would forage for and eat in their home country, so do not pick them here as they're not the same.

Symptoms of deathcap mushroom poisoning include vomiting, diarrhoea and stomach cramps and usually appear 10 to 16 hours after eating. These symptoms may ease for two to three before a terminal phase of three to four days begins. Without early, effective medical intervention people may go into a coma and die after two or three weeks of liver and kidney failure.

While rare, most deaths from mushroom poisoning in Australia result from deathcap mushrooms. But there are other wild mushrooms in Australia that have caused fatalities or can make people seriously ill with abdominal pain, vomiting and diarrhoea. These include the Cortinarius (webcap) and Galerina species, the ghost mushroom (commonly mistaken for oyster mushrooms), and the yellow stainer which resembles a field mushroom and is the most commonly ingested poisonous mushroom in Victoria and New South Wales.

Cathy said many accidental exposures to poisonous mushrooms are in children under 5 years.

"Remember that small children have a natural inclination to put things in their mouths, especially if they are colourful and attractive. So, keep an eye on them when outdoors," she said.

"Parents, school and childcare workers should regularly check outdoor areas and gardens for mushrooms and remove them to reduce the risk of them being eaten accidentally. This will also protect your pets."

If you suspect you or your child may have eaten a deathcap mushroom, don't wait for symptoms to occur.

Go to a hospital emergency department straight away, taking the mushroom with you if you can.

You can also contact the Poisons Information Centre from anywhere in Australia on 13 11 26 (24 hours a day 7 days a week).