Herbal medicines and dietary supplements purchased from pharmacies and health food stores in Australia have been found to contain a wide range of contaminants including DNA from rats, dogs and pigs.

When WA pharmaceutical chemists analysed 135 complementary and alternative medicine (CAM) products they found that most were adulterated, fraudulent or contaminated and only 21% contained exactly what was stated on the label.

Their investigation focused on herbal medicines and supplements promoted for diet, weight loss and cardiovascular health, of which almost two thirds (63%) were listed by the TGA and bought from pharmacies and health food shops, the remainder being purchased online.

Using DNA ‘barcoding’ and mass spectrometry the scientists found that of the 82 samples that had amplifiable DNA:

• Half contained undeclared plant-based fillers based on wheat, rice, soybean and grasses or DNA from nuts.
• One in five (21%) had animal contamination (DNA from species such as dog, pig, rat, mouse or cow).
• DNA from frog, reindeer and shrew was detected in tonics and teas promoted for detox and slimming.
• A ‘shark cartilage’ product was found to contain DNA suggesting the cartilage may have come from other animals, possibly chicken.
• One in 20 products (5%) contained undeclared pharmaceutical ingredients including pseudoephedrine, chlorpheniramine [an antihistamine] and paracetamol. Caffeine was a common undeclared ingredient.

The researchers, from Murdoch University’s  Department of Medical Molecular and Forensic Sciences, said the findings suggested that only a minority of the 11,000 CAM products listed on the Australian Register of Therapeutic Goods complied  with TGA regulations for quality control and listed ingredients.

They said the presence of undeclared ingredients such as wheat and nuts in CAM products was a safety concern for people with conditions such as coeliac disease and nut allergy.

Similarly the presence of undeclared pharmaceuticals such as paracetamol was an obvious toxicity hazard for overdose and drug interactions, they warned.

“This study has shown that contaminated and adulterated products are not minor, niche-market remedies, but are sold in some of the biggest health food stores and pharmacies in Australia,” they wrote in the Journal of Pharmaceutical and Biomedical Analysis.

“The fact that [we] could purchase these products suggests a failure in regulatory control, demonstrating a clear need to strengthen the regulation of these products to improve consumer safety.”