A 98-year-old Australian woman has died after she and her son ate poisonous mushrooms they had picked from their garden in Melbourne.

Loreta Del Rossi passed away on May 22 after suffering a fatal bout of multi-organ failure which was triggered by toxins in the “death cap” mushrooms.

She often grew her own vegetables in the garden and would regularly forage for wild greens.

In April she came across a patch of mushrooms in her front yard and decided to use them for dinner.

She didn’t suffer any illness from that meal, and on May 15 found more mushrooms in her garden and used them again to make a tuna and rice dish.

It was reported that she thoroughly washed, cleaned, and tested the white mushrooms.

However, this time Del Rossi and her son both fell severely ill and were rushed to hospital.

The toxin in death cap mushroom (amanita phalloides) stops human cells dividing, affecting organs such as the liver. Photo / Supplied

Del Rossi’s condition worsened and she died a week later. Her son survived.

Coroner Judge John Cain released his findings on Wednesday, saying the mother and son had consumed a death cap mushroom which is often pale yellow, green or whitish in colour.

He confirmed she died from organ failure following amanita poisoning, the toxin found in both death cap and yellow-staining mushrooms.

The amatoxins found in these mushrooms are lethal in small doses, where a 50g mushroom can deliver a fatal dose to a 70kg adult.

Despite the Victoria health department publishing an advisory on wild mushroom consumption, the coroner said there needs to be improved public messaging to avoid further tragic deaths.

“I commend the Department of Health for publishing a health advisory regarding the consumption of wild mushrooms,” he said in a statement.

“However, I believe that additional public awareness is merited.”

The death came nearly a year after three people died following a fatal beef wellington lunch.

Erin Patterson, the Australian woman who cooked the mushroom meal that killed three people, pleaded not guilty to charges of murder and attempted murder.

Erin Patterson is accused of murdering her former father-in-law Don Patterson, his wife Gail, and Gail’s sister Heather Wilkinson after they ate poisonous mushrooms in the meal at her home on July 29 last year.

All three died in hospital days afterwards. Heather’s husband Ian Wilkinson miraculously survived after he spent two months in hospital.

Erin Patterson pleaded not guilty to three counts of murder and five counts of attempted murder.

Three of her attempted murder charges are related to her estranged husband following “three separate incidents” where he fell ill between 2021 and 2022.