This study investigated whether herbal products on the north american market were contaminated. The results are worrying.
Most of the herbal products tested were of poor quality, including considerable product substitution, contamination and use of fillers.
Most (59%) of the products tested contained plant species not listed on the labels. Although we were able to authenticate almost half (48%) of the products, one-third of these also contained contaminants and or fillers not listed on the label. Product substitution occurred in 30/44 of the products tested and only 2/12 companies had products without any substitution, contamination or fillers. Some of the contaminants we found pose serious health risks to consumers.