The University of Washington is warning students and staff to avoid eating potentially deadly mushrooms that have turned up on the school’s Seattle campus.
“Highly toxic ‘death cap’ (Amanita phalloides) mushrooms were found by UW Facilities staff,” school leaders warned in an alert on Wednesday. “Death cap mushrooms appear similar to edible mushrooms, but are poisonous and should be avoided.”
The death cap mushroom is to blame for most mushroom-related deaths across the globe, according to the U.S. Centers for Disease Control and Prevention.
“If a person eats a mushroom containing amanita toxins, the health effects may include liver failure, kidney failure and death,” the alert said. “Symptoms include nausea, stomach cramps, pain and diarrhea. The onset of symptoms may be delayed by six to 24 hours after consumption.”
The school asked people to report mushrooms they think are toxic to UW facilities workers.
Differentiating between safe mushrooms and poisonous ones isn’t always easy, according to the California Department of Public Health.
“Telling the difference between wild mushrooms that are safe and those that are poisonous can be difficult for many people,” state Public Health Officer Dr. Karen Smith said in a statement last year. “Wild mushrooms should not be eaten unless they have been examined by a mushroom expert and determined to be edible.”
More than 1,000 cases of people eating poisonous mushrooms were reported to the California Poison Control System just from November 2016 to Jan. 15, 2018, according to the Department of Public Health. Of those cases, 16 were admitted to intensive care units and 433 were kids under the age of 6.
The mushroom isn’t native to North America at all: Canadian researchers wrote in 2016 that the death cap “is an invasive ectomycorrhizal fungus in North America that was inadvertently introduced from Europe.”
The dangerous variety of mushroom was first reported on the continent in Monterey, California, in 1938, but can now be found from Los Angeles up to British Columbia, as well as on the East Coast, researchers said.