Oct 11 2013: A research team based out of the University of Guelph recently published their analysis of 44 herbal products available in stores across Canada, showing a high rate of contamination. The researchers used a DNA matching technique to identify species of herbs present in these products, and compare them to those listed on the product labels.

Herbal products available to consumers in the marketplace may be contaminated or substituted with alternative plant species and fillers that are not listed on the labels. According to the World Health Organization, the adulteration of herbal products is a threat to consumer safety. This study aimed to investigate herbal product integrity and authenticity with the goal of protecting consumers from health risks associated with product substitution and contamination.

A DNA test was used to test the authenticity of 1) 44 herbal products representing 12 companies and 30 different species of herbs, and 2) 50 “raw” leaf samples collected from 42 herbal species. Researchers found that most of the products tested (59%) contained DNA from plant species not listed on the labels. Product substitution occurred in 30 of 44 of the products tested, and only 2 of 12 companies had products without any substitution, contamination or fillers. Some of the contaminants identified may pose serious health risks to consumers.

Researchers suggested that companied incorporate a DNA herbal barcode library for testing bulk materials in order to authenticate materials used. The study also underscores the need for consumers to seek out only high quality natural health products.