Two people have been hospitalised in San Francisco after drinking tea from the same Chinatown herbalist.
The city’s public health department said on Friday that the tea leaves bought at Sun Wing Wo Trading Company contained the plant-based toxin aconite.
Health officials said a man in his 50s and a woman in her 30s became critically ill within an hour of drinking the tea. The first incident occurred in February and the second was in early March but both remained in hospital.
They both became weak after drinking the tea and then had life-threatening abnormal heart rhythms that required resuscitation and intensive care.
Aconite, also known as monkshood, helmet flower or wolfsbane, is used in Asian herbal medicines. But it must be processed properly to be safe.
Health officials are working to find the original source of the tea leaves. They have warned people not to drink tea from Sun Wing Wo.
“Anyone who has purchased tea from this location should not consume it and should throw it away immediately,” said Tomás Aragón, health officer for the city and county of San Francisco. “Aconite poisoning attacks the heart and can be lethal.”