DNA technique can detect contaminants in supplements
University of Guelph researchers develop way to test natural health products
Researchers at the University of Guelph have developed a new DNA technique to identify if contaminants are present in natural health products with more than one ingredient, such as natural medicines. It can also be used to test food quality.
The technique was first tested in a recent study on Chinese patent medicine, or Chinese medicine that comes in pill, tablet and capsule forms, 80 per cent of which was found to contain ingredients that were not on the label.
“This is quite a breakthrough for industry,” said Steven Newmaster, a professor at Guelph’s integrative biology department and co-author of the study, which was published in Nature, a top-tier scientific journal.
“Before the study, you wouldn’t be able to take the mixture and disentangle all the species and say they’re there for quality testing. Now you can,” he said.
The technology will allow industry users, such as Chinese pharmaceutical giants or supplement companies like Canada’s Jamieson Vitamins, to conduct quality-assurance checks more effectively, he said.
Regulatory bodies can also benefit. Instead of going through the long and expensive process of extracting and sequencing DNA, the technique scans the product for “DNA signatures.” This probe picks up on the individual species or ingredients within a mixture and can be done in less than an hour, rather than waiting up to two weeks for test results in previous methods.
Newmaster said that, in his experience, working with companies in the natural health product industry, “innocent contamination” of products can occur simply from how complex the supply chains are. Other times, substituting ingredients is intentional.
“Some of it is actually economically motivated adulteration (and) substitution . . . put something in cheap rather than a more expensive ingredient,” he said.
The study notes that illegal supply chains and counterfeit plant medicines can be a “considerable” threat to consumer health.
Adina Stanescu, a traditional Chinese medicine practitioner and herbalist at the TCM Clinic in Toronto, cautions clients from picking up low-cost, off-the-shelf treatment.
“It ends up being that people may self-treat or they just quickly ask the shop owner,” she said.
She said patients should consult with a clinic to avoid the risk of taking an ineffective treatment, especially when lower-grade ingredients or substitutions may be found in the pills.
Strain on the supply chain for some botanical species, such as honeysuckle, used to treat lung conditions including cold and flu symptoms, can put pressure on manufacturers to find substitutes, Newmaster said.
The technique in his study is “disruptive” to the industry, he said, and will change the way companies detect and combat dummy ingredients.
“Canadian technology in DNA diagnostics is kind of leading the way for good quality food, quality assurance in food and natural health products.”