American Herbal Product Association (AHPA) President Michael McGuffin wrote a letter to the editor criticizing inaccuracies in a recent article, "DNA barcoding detects contamination and substitution in North American herbal products," published in BMC Medicine.
Despite confusing conclusions and questionable methodology, the article sparked alarming headlines across the country about the prevalence of contamination in supplements after the New York Times summarized the BMC Medicine report in an article published on Nov. 3. AHPA is contacting newspapers that covered the BMC Medicine article to inform them about the significant issues that undermine the article's credibility.
The BMC Medicine article inaccurately states that, "There are currently no best practices in place for identifying the species of the various ingredients used in herbal products." It then draws a conclusion from this unsubstantiated statement saying that, "As a result, the marketplace is prone to contamination and possible product substitution ..."
In response, McGuffin informed the editors that all herbal products marketed in United States must comply with the Food and Drug Administration's (FDA's) current Good Manufacturing Practice (cGMP), which includes a provision that requires manufacturers to verify the identity of all herbal ingredients using scientifically valid methods."
McGuffin also questioned the methods the authors used to test the herbal supplements for the article.
"The article presents its findings as if DNA barcoding has been validated for the identification of each of the tested botanicals," McGuffin wrote. "But this is an emerging technology and there are still many questions about the effectiveness and limitations of this method. DNA testing has the potential to be useful in the future when it has been rigorously tested, but the article's blanket assertions about the accuracy of this novel analytical tool are premature."
McGuffin concluded by urging the authors to identify the products tested for the article.
"Omitting the names of the products tested is a disservice to companies that verify the identity of the ingredients in their products using scientifically valid methods like chromatography, microscopy and organoleptic analysis by qualified experts," McGuffin wrote. "These companies' reputations should not be tarnished and AHPA urges the authors of the paper to disclose the identity of the tested products."