SAN FRANCISCO (KGO) -- A lawsuit has been filed in the case of a dead woman poisoned after ingesting some herbs from a shop in San Francisco's Chinatown. A second person was also hospitalized but survived.
RELATED: Death of tea consumer shocks San Francisco's Chinatown
Jin Deng remembers his mother becoming very ill just one hour after taking a specialty tea blend prescribed by a Chinese herbalist.
For an entire month, doctors tried unsuccessfully to save her life.
"We told her, that, 'Mom, they're going to have to cut off your leg because it's making you very very sick and the only chance to save your life is to do this,' and she understood," said Deng.
The San Francisco Health Department found traces of aconite in her urine and in the tea she was drinking.
After being processed, aconite can be safely used to treat pain.
Attorney Charles Kelly questioned who was manufacturing the tea and putting it on the market.
RELATED: Woman dies after drinking toxic tea from San Francisco's Chinatown
A study out of Hong Kong documented 52 cases of aconite poisoning between 2004 and 2009. The purpose of the study was to determine the causes that lead to the kind of poisoning that killed Yu-Ping Xie.
In most cases it was due to poor-quality herbs, or an error at the time it was dispensed.
The herbs were purchased at Sun Wing Wo Trading Company. The family confronted owner Yui-Wan Chan. ABC7 News couldn't reach her either.
The owner is being investigated by the health department.
The son says his mother never left the hospital. "Doctor basically told us there was nothing they could do, so then we chose to let her go comfortably."
RELATED: Two hospitalized by poison tea from SF Chinatown
A man was also hospitalized after consuming a tea blend made at the same store and is recovering.