Illegal ingredients found in traditional Chinese medicines

April 13, 2012

Print This Post Print This Post

For the first time, researchers at Murdoch University have used new DNA sequencing technology to reveal the animal and plant composition of traditional Chinese medicines (TCM) – with worrying results.

Research leader and Murdoch University Australian Research Council Future Fellow, Dr Mike Bunce, said that some TCMs contained potentially toxic plant ingredients, allergens and even traces of endangered animals.

“TCMs have a long cultural history but today, consumers need to be aware of the legal and health safety issues before adopting them as a treatment option,” Dr Bunce said.

Fifteen TCM samples, seized by border officials, in the form of powders, tablets, capsules, flakes and herbal teas were audited using the DNA preserved in the samples. The results are published in the journal PLoS Genetics.

“In total we found 68 different plant families in the medicines – they are complex mixtures of species,” Dr Bunce said.

“Some of the TCMs contained plants of the genus Ephedra and Asarum. These plants contain chemicals which can be toxic if the wrong dosage is taken, but none of them actually listed concentrations on the packaging”.

“We also found traces from trade restricted animals that are classified as vulnerable, endangered, or critically endangered, including the Asiatic black bear and Saiga antelope.”

Until now it has been difficult to determine the biological origins of ingredients contained within TCMs because processing into pills and powders makes identification difficult.

PhD student Megan Coghlan, who is studying the application of DNA techniques in wildlife forensic applications, said the research shows that second-generation, high throughput sequencing is an efficient and cost-effective way to audit the species composition.

“The approach has the ability to unravel complex mixtures of plant and animal products,” Ms Coghlan said.

Further testing of TCMs would reveal the extent of the problem and make it easier for custom officials to identify the trade of endangered species.  The increasing popularity of the medicines has seen the value of the industry increase to hundreds of millions of dollars per annum – not good news for rare animals that are hunted and killed for use in TCMs.

“We found multiple samples that contained DNA from animals listed as trade-restricted according to the Convention on International Trade in Endangered Species Legislation. Put simply, these TCMs are illegal,” Ms Coglan said.

Another worrying concern is the mislabelling of TCMs meaning consumers are unaware of the presence of some ingredients including animal DNA and potentially allergens such as soy or nuts.

“A product labelled as 100 per cent Saiga antelope contained considerable quantities of goat and sheep DNA,” Dr Bunce said.

“Another product, Mongnan Tianbao pills, contained deer and cow DNA, the latter of which may violate religious or cultural strictures.”

Incorrect labelling makes it difficult to enforce legislation and to prosecute cases of illegal trade.

“It is hoped that this new approach to genetically audit medicinal products will bring about a new level of regulation to the area of complementary and alternative medicine,” Dr Bunce said.

“Auditing TCMs would assist in prosecuting individuals who seek to profit from the illegal trade in animal products.”

Dr Bunce and his team have applied for funding from the Australian National Health and Medical Research Council (NHMRC) to expand the use of these new DNA tests to evaluate other herbal medicines.

The Australian Customs and Border Protection Service and the International Wildlife Trade Section (Department of Sustainability, Environment, Water, Population and Communities) supplied the seized TCM samples that were tested in the research.

The research was conducted at the Australian Wildlife Forensic Services, Ancient DNA Laboratory and the Centre for Comparative Genomics, all based at Murdoch University.

Comments (3 responses)

Samantha April 27, 2012

Hi,

I just wanted to say, as an environmentalist and fellow (low level) scientist, that this is very inspiring work. I'm doing my Grad Dip Ed Secondary to teach Science and would love to be able to incorporate some of this into my teaching in the future. I hope this is being aired far more publicly than the Murdoch website.

Great job, keep it up!

Sam

giles November 17, 2012

What a waste of time and expensive research for a media friendly story. TCM products would have contained ephedra and asarum species as these are standard chinese medicinals, albiet ones that are scheduled in Australia. Yes, medicines can be toxic if too great a dose is taken, but there would have been recommended doses on the packets.

I'm guessing the product that contained the illegal animal product from saiga antelope would have been the one that was labelled 100% saiga antelope. Surely DNA sequencing wasn't necessary to discover this.

The chinese medicine that is becoming popular in Australia is practiced by university trained registered professional who are perfectly aware of which medicinals should not be used because they are illegal, or come from endangered species, and who know the correct doses for the medicinals, and are just as aware of any potential toxicity issues as any other type of medical practitioner.

Chinese medicine practitioners do not need DNA sequencing to know that many commercial chinese medicine products are adulterated – it's common knowledge. The adulterants are often pharmaceutical rather than unlabelled chinese medicine medicinals. It would be useful if you would make it public which products were adulterated, rather than indiscriminately slandering an entire health modality.

Mike Bunce November 19, 2012

Dear Giles – thanks for taking the time to put your opinions into writing. You are however misguided in several areas – recent research shows that any dose of Aristolochic acid (found in asarum) is carcinogenic – are you advocating that it is OK for people in Australia (or elsewhere) to buy a product when its carcinogenic ingredient is not declared. Adulterated medicines are not acceptable the fact that (you state) that it is common knowledge does not make it any less of a problem. No doses were found on products contain Ephedra (so you are wrong on this count as well).

Endangered animals were found in TCM's that were not labelled as such (for example Asiatic Bear) – and goat and sheep DNA was found in the 100% Saiga Antelope horn powder (how would you discover this without DNA sequencing). Frankly, I am shocked that you would think that this is OK? We have recently expanded this work to products sold here in Australia and the products are equally problematic.

"It would be useful if you would make it public" – this research is already public – we published our paper and sequence in an open access journal and I would encourage you to take the time to read the science. http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1002657

Leave a comment

You can use these tags : <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

We read every comment and will make every effort to approve each new comment within one working day. To ensure speedy posting, please keep your comments relevant to the topic of discussion, free of inappropriate language and in-line with the editorial integrity of this newsroom. If not, your comments may not be published.

Thanks for commenting!