Nearly all of the herbal dietary supplements tested in a Congressional investigation contained trace amounts of lead and other contaminants, and some supplement sellers made illegal claims that their products can cure cancer and other diseases, investigators found.
The levels of heavy metals — including mercury, cadmium and arsenic — did not exceed thresholds considered dangerous, the investigators found. However, 16 of the 40 supplements tested contained pesticide residues that appeared to exceed legal limits, the investigators found. In some cases, the government has not set allowable levels of these pesticides because of a paucity of scientific research.
The report focused on herbal supplements like Ginko and St. John’s Wort. The levels were low as noted:
GAO also found trace amounts of at least one potentially hazardous contaminant in 37 of the 40 herbal dietary supplement products tested, though none in amounts considered to pose an acute toxicity hazard. All 37 supplements tested positive for trace amounts of lead; of those, 32 also contained mercury, 28 cadmium, 21 arsenic, and 18 residues from at least one pesticide. The levels of heavy metals found do not exceed any FDA or Environmental Protection Agency (EPA) regulations governing dietary supplements or their raw ingredients, and FDA and EPA officials did not express concern regarding any immediate negative health consequences from consuming these 40 supplements.
Earlier this year, Kirkman Labs (who markets their supplements towards the autism parent community) was found to have a number of supplements contaminated with antimony.
A representative for the Council for Responsible Nurtirion downplayed the contamination issues:
Steve Mister, president of the Council for Responsible Nutrition, a trade association representing the dietary supplement industry, said it was not surprising that herbal supplements contained trace amounts of heavy metals, because these are routinely found in soil and plants. “I don’t think this should be of concern to consumers,” Mr. Mister said.