Toxic tea from Chinatown shop in SF sends 2 to hospital

A woman in her 50s and a man in his 30s became sick within an hour of sipping a tea made from leaves sold by the Sun Wing Wo Trading Co., an herbalist at 1105 Grant Ave. A woman in her 50s and a man in his 30s became sick within an hour of sipping a tea made from leaves sold by the Sun Wing Wo Trading Co., an herbalist at 1105 Grant Ave. Photo: Google Maps Photo: Google Maps Image 1 of / 1 Caption Close Toxic tea from Chinatown shop in SF sends 2 to hospital 1 / 1 Back to Gallery

Two people are critically ill and remain hospitalized after consuming a toxic herbal tea bought on Grant Avenue in Chinatown, according to the San Francisco Department of Public Health.

In separate incidents in February and March, a woman in her 50s and a man in his 30s became sick within an hour of sipping a tea made from leaves sold by the Sun Wing Wo Trading Co., an herbalist at 1105 Grant Ave.

Both victims rapidly developed weakness, followed by life-threatening abnormal heart rhythms that required resuscitation and intensive hospital care. A plant-based toxin, aconite, was found in lab tests of the patients and the tea samples they provided.

Inspectors from the city’s health department are removing the products consumed by the two patients from the shelves at Sun Wing Wo Trading Co. The health department is also working with the shop owner to trace the source of the contamination and ensure that no future customers are exposed to it.

“Anyone who has purchased tea from this location should not consume it and should throw it away immediately,” said Dr. Tomás Aragón, health officer for the city. “Aconite poisoning attacks the heart and can be lethal.”

Known to treat pains, bruises and other conditions, aconite — also called called monkshood, helmet flower, wolfsbane, chuanwu, caowu and fuzi — has been used in Asian herbal medicine for thousands of years. While the plant’s raw flowers are highly toxic in their natural state, once properly processed, they can be safely consumed. There is no antidote for aconite poisoning.

While people who have purchased and consumed the tea without experiencing symptoms are safe, they should stop consuming it, according to health officials. Anyone who experiences symptoms after consuming the tea should call 911 or go immediately to the nearest hospital. Symptoms usually begin within a few minutes or up to a couple hours and can include: numbness or tingling of the face, mouth or limbs; weakness in the limbs; paralysis; low blood pressure; chest pain; palpitations; nausea and diarrhea.

The connection to the Sun Wing Wo Trading Co. emerged after both cases were referred to the California Poison Control System at San Francisco General Hospital.

“The investigation is just starting, but we know that the tea in both instances came from the same place,” said Rachael Kagan, spokeswoman for the San Francisco Department of Public Health. “And in each instance the person had drank the tea recently.”

A woman who answered the phone at the herbal shop said she could not comment.

J.K. Dineen is a San Francisco Chronicle staff writer. Email: jdineen@sfchronicle.com Twitter: @sfjkdineen