Be careful what you buy: A side-by-side comparison of the raw herb mutong (bottom) and its adulterated cousins guan mu tong and chuan mu tong (top). -Pic courtesy of Dr Yam Mun Fei
PETALING JAYA: A traditional Chinese medicine expert wants the Health Ministry to implement stricter control on the import of herbs, saying his research has found that Chinese medicine halls are selling adulterated raw herbs.
Dr Yam Mun Fei, a pharmacologist who is a member of the Federation of Chinese Physician and Medicine Dealers Association, studied more than 130 herb samples collected from medicine halls in all 13 states.
The USM lecturer found that merchants were mistakenly selling a herb species known to contain aristolochic acid, a banned substance in Malaysia.
His research showed that medicine halls were replacing mu tong (akebiae caulis), a herb commonly used as a diuretic, with guan mu tong (aristolochiae manshuriensis caulis).
He said long-term consumption of guan mu tong could lead to kidney failure.
Dr Yam said another herb known as chuan mu tong (caulis clematidis armandii) was also being mistakenly sold as mu tong, only that this herb is harmless.
To the untrained eye, these three herb species look identical.
"If you do not have professional knowledge, you will not be able to differentiate between these herbs," Dr Yam said, adding he used scientific analysis to identify them.
He said merchants could be unintentionally selling the wrong herb species due to a lack of knowledge, but there could also be irresponsible merchants out to make a profit.
This further highlighted the need for a system or SOP to control the import and export of raw herbs, mainly those from China, Dr Yam said.
Existing laws under the National Pharmaceutical Regulatory Agency regulate herbs that have been processed into pharmaceutical form but exempted raw herbs sold in powder or dry form from registration or testing.
Dr Yam said while most raw herbs were harmless, it still needed to be regulated as it could be contaminated with herbicides, pesticides or heavy metals.
"If you take some random sample of herbs in the market and analyse, I can guarantee that its heavy metal level is more than the suggested level by the Health Ministry," he said.
To protect end users, Dr Yam said a national monograph or pharmacopoeia for imported herbs was needed to complement the existing monograph for local herbs.