A new study out of Australia looked at 26 different Traditional Chinese Medicine (TCM) products purchased from stores. They performed three types of analysis: heavy metal screening, toxicological analysis, and DNA sequencing. They found that 92% of the products tested had at least one type of contaminant.
This adds to a growing list of studies and revelations about how poorly the supplement industry is regulated, and raises further concerns about the overall quality of herbal and supplement products.
A 2008 study found that about 20% of ayurvedic herbal products contained heavy metal contamination, often at levels high enough to be toxic.
“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.”
A 2014 study published in JAMA found that half of the product recalled by the FDA for being adulterated with banned drugs were dietary supplements, including up to one third of products purchased online. Further, when the FDA followed up they found that 6 months after they had issued a recall for adulterated supplements, two-thirds were still on the market and still contained the banned drugs.