DNA testing of traditional Chinese medicines has shown that many contain traces of endangered animals.
Scientists who analysed 15 samples of powders, pills, capsules and herbal teas found "multiple" examples of banned animal ingredients.
Some of the samples also contained potentially toxic plant compounds and allergy triggers. The traditional Chinese medicines (TCMs) studied were among products seized by Australian border officials.
Dr Michael Bunce, from Murdoch University in Western Australia, said: "In total we found 68 different plant families in the medicines - they are complex mixtures of species. Some of the TCMs contained plants of the genus Ephedra and Asarum. These plants contain chemicals that 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 TCMs processed into pills and powders.
The new research, published in the online journal Public Library of Science Genetics, used high-throughput DNA sequencing to unravel the complex mixtures of plant and animal ingredients.