The fungi believed to be involved in a possible triple homicide case in Australia can also be found in Canadian forests, prompting concerns about its presence in the country.
The Australian incident gained significant attention this week when police revealed that they suspect “death cap” mushrooms were served at a family lunch in July, leading to the deaths of three of the four people who were present. Erin Patterson, 48, has been accused of serving Amanita mushrooms to her former parents-in-law, her mother-in-law’s sister, and her critically ill husband, according to the police. The case is being treated as a homicide investigation, although Patterson has denied any wrongdoing.
This tragedy raised awareness among Canadians, who began searching for information on whether these poisonous mushrooms could be found in Canada. It turns out that “death cap” mushrooms do grow in certain parts of Canada, particularly in British Columbia.
The B.C. Provincial Health Services Authority (PHSA) has confirmed that “death caps” can be found in the Lower Mainland, the Fraser Valley, and on Vancouver Island, primarily in “urban areas.” These mushrooms thrive in wet conditions, usually appearing in late fall, but they can also emerge in summer in places that are regularly watered.
Just last month, a young child ingested one of these mushrooms, leading the provincial health authority to issue a warning. Fortunately, the child survived, but the incident serves as a cautionary tale about the extreme toxicity of “death cap” mushrooms, which can cause liver damage and even death.
Symptoms of poisoning from “death caps” typically include abdominal pain, vomiting, diarrhea, and dehydration occurring eight to 12 hours after ingestion, followed by a second wave of symptoms after 72 hours, including low blood pressure, liver and kidney failure, and seizures, as explained by the B.C. Centre for Disease Control.
This type of mushroom is responsible for the most fatal mushroom poisonings globally, according to the center.
The B.C. CDC advises anyone who suspects they’ve ingested one of these potentially lethal fungi to seek immediate medical attention at an emergency room.
A study published earlier this year indicated that there have been around 100 sightings of “death cap” mushrooms across B.C., and it suggests that these sightings are likely to increase as the mushrooms continue to spread.
Researchers from Cold Spring Harbor Laboratory published the study in January, outlining how “death caps” are capable of rapid reproduction. The study suggests that these mushrooms can multiply “by single individuals,” and it highlights the diverse reproductive strategies that contribute to their rapid spread, drawing parallels with plant, animal, and fungal invasions.
At the time of publication, the study had not yet undergone peer review.
In Canada, “death caps” are considered an invasive species. They resemble Asian straw mushrooms and other varieties that grow within cities, along tree roots, and on logs. The officials in British Columbia encourage people to report sightings of these mushrooms for safe removal.