DNA Tests Show Fraud and Contamination Common in Herbal Products
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Celiac.com 12/16/2013 - Numerous popular herbal products may be contaminated or may contain unlabeled substitute ingredients and fillers, meaning that they are not what their labels claim. According to the World Health Organization, adulterated herbal products are a potential threat to consumer safety.
These revelations came to light after a group of Canadian researchers conducted an investigation into herbal product integrity and authenticity, with hopes of protecting consumers from health risks associated with product substitution and contamination.
Using a test called DNA barcoding, a kind of genetic fingerprinting that been effective in uncovering labeling fraud in other commercial industries, the researchers found that nearly 60% of herbal products tested were not what their label claimed them to be, and that pills labeled as popular herbs were often diluted or replaced entirely, sometimes with cheap fillers that could be dangerous to consumers.
In all, the researchers tested 44 herbal products from 12 companies, along with 30 different species of herbs, and 50 leaf samples collected from 42 herbal species.
The researchers were Steven G. Newmaster, Meghan Grguric, Dhivya Shanmughanandhan, Sathishkumar Ramalingam and Subramanyam Ragupathy. They are variously affiliated with the Centre for Biodiversity Genomics, Biodiversity Institute of Ontario (BIO) at the University of Guelph, the Bachelor of Arts and Science Program at the University of Guelph in Guelph, Ontario, Canada, and with the Plant Genetic Engineering Laboratory, Department of Biotechnology, Bharathiar University in Tamil Nadu, India.
Their laboratory also assembled the first standard reference material (SRM) herbal barcode library from 100 herbal species of known provenance that were used to identify the unknown herbal products and leaf samples.
The team recovered DNA barcodes from most herbal products (91%) and all leaf samples (100%), with 95% species resolution using a tiered approach (rbcL + ITS2).
Nearly 60% of the products tested contained DNA barcodes from plant species not listed on the labels. That means they were not what the label said they were.
Furthermore, even though 48% of the products contained authentic ingredients, one-third of those also contained contaminants and/or fillers not listed on the label.
The air data showed clearly that most herbal products tested were not what their labels claim, while most of the rest were poor quality, and often contained unlabeled, possibly dangerous, product substitute, contamination and fillers.
They note that selling weak, ineffective, or mislabeled herbal supplements reduces the perceived value of otherwise helpful products by eroding consumer confidence.
The study team recommends that the herbal industry embrace DNA barcoding to ensure authentic herbal products by effectively documenting raw manufacturing materials.
They suggest that the use of an SRM DNA herbal barcode library for testing bulk materials could provide a method for 'best practices' in the manufacturing of herbal products, and note that this would provide consumers with safe, high quality herbal products.
What do you think? Should herbal products and supplements be tested, authenticated and verified? Share your thoughts below.
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