Traditional Chinese medicine (TCM) has become quite popular in recent years. TCM includes herbal medications, acupuncture, massage and exercise. While it may be considered alternative medicine in the western world, TCM is a common part of medical care in east Asia. Hundreds of millions of dollars are spent on TCM products, with much of it being spent on the Internet. Researchers have noted in the past however that some mixtures can also contain contaminants like heavy metals, as well as naturally occurring toxins. New studies “show very clearly how dangerous the products of TCM can be,” according to Fritz Sorgel, of the Institute for Biomedical and Pharmaceutical Research in Nuremberg, Germany.
Researchers at Murdoch University in Australia analyzed samples of TCM seized by Australian border officials. The researchers found Ephedra and Asarum plants in some of the herbal preparations. Both can contain toxic chemicals such as aristolochic acid which can cause kidney disease and cancer of the upper urinary tract. The dangers of aristolochic acid is also reviewed in a paper published in the Proceedings of the National Academy of Sciences. The researchers, led by pharmacologist Arthur Grollman of Stony Brook Unversity studied Taiwan, the country with the highest rate of upper urinary tract cancer in the world. Earlier research had shown that approximately one-third of the Taiwanese population consumed herbs likely to contain aristolochic acid. The Stony Brook study found compelling evidence that aristolochic acid is a primary cause of cancer of the upper urinary tract of people living in Taiwan.
Molecular geneticist Michael Bunce at Murdoch University and his colleagues also found DNA in some TCM that could pose risks when used in combination with other drugs. “This just shows that the ingredients in these preparations aren’t accurately declared,” says Bunce. Adds Sorgel, “We just don’t know enough about it.” ScienceNow 4/16/12