THE highly toxic amatoxins found only in death cap mushrooms, including alpha-amanitin and beta-amanitin, were detected in urine samples provided by one of the victims of the poisonous beef Wellington lunch, Korumburra’s Don Patterson, at the Dandenong Hospital at 9.01pm on Sunday, July 30, 2023.
These details, as well as laboratory analysis of samples from the other victims of the mushroom meal, together with the leftovers and residue from the food dehydrator were provided to the court on Day 12 of Erin Patterson’s triple murder trial by Head of Forensic Science at the Victorian Institute of Forensic Medicine Dr Dimitri Gerostamoulos.
An expert witness in literally hundreds of cases where poisoning has been alleged, Dr Gerostamoulos, also a toxicologist, pharmacologist and Adjunct Associate Professor in the School of Public Health and Preventive Medicine at Monash University said there had also been positive results from Ian Wilkinson’s blood serum and urine for the beta-amanitin toxin.
Dr Gerostamoulos said laboratory analysis had also been performed on the leftovers from the meal, recovered by Mirboo North Senior Constable Adrian Martinez-Villalobis from a red-lid rubbish bin outside Erin Patterson’s house on Monday, July 31 when he visited the address with Leading Senior Constable Kate Mulry.
Photos were shown to the court of four pieces of the leftover beef Wellington pasties, on individual trays with Dr Gerostamoulos acknowledging that mushroom paste from the leftovers as well as a meat sample both tested positive for the beta-amanitin toxin.
A small amount of material recovered from the Sunbeam Food Lab Electronic Dehydrator, which Erin Patterson allegedly purchased from Hartley Wells in Leongatha on April 28, 2023, and recovered later from the Koonwarra tip, was also tested with both alpha-amanitin and the beta-amanitin toxins detected in three individual samples taken from the dehydrator.
“And is it your evidence that they are exclusively associated with death cap mushrooms?” asked prosecution lawyer Sarah Lenthall.
“Yes, they are,” said Dr Gerostamoulos.
It was the evidence of Dr Gerostamoulos that none of the nine samples provided by Erin Patterson, including blood and serum, tested positive for any of the death cap mushroom toxins.
He also said that it was estimated that 50 grams or three table spoons amatoxins constituted a lethal dose for a 70 kilogram adult.
His evidence will continue on Friday in the Supreme Court at Morwell.