In response to questions from NutraIngredients-USA, a spokesperson for the Office of the Attorney General told us: "We will not be publishing the data for peer review. Our data is part of an ongoing investigation."
In response to a question regarding the suitability of evolutionary biologist Dr James Schulte to test botanical finished products, the Office said: “Rather than attacking testing methods that have been validated by more than 70 published papers, the time has come for the herbal supplements industry to put concerns about what is and is not included in their products to rest.
"The fact is virtually every product we tested includes ingredients not listed on the packaging, and close to 80% failed to show any evidence that they included even trace amounts of what was advertised. This is ultimately a matter of public health, and when public health is at stake the burden is on this largely unregulated industry to prove what's in its products.”
The University of Guelph study was published in 2013 in the open access journal BMC Medicine. Researchers led by Prof Steven Newmaster used DNA barcoding technology to test 44 herbal products sold by 12 companies. Their results indicated that only two of the companies provided authentic products without substitutions, contaminants or fillers.
Overall, nearly 60% of the herbal products contained plant species not listed on the label, and product substitution was detected in 32% of the samples.
That paper was widely criticized by analytical and botanical experts and the American Botanical Council called for it to be retracted.
Methodology and experimental details
In response to our questions, “Could you share details of the study with me, particularly in terms of which of the products tested were extracts – did you characterize all of the products?” and “Can you share the methodology used?”, a spokesperson for the AG stated: “I’ve attached the letters that were sent to the four retailers, which detail the study”.
The attached letters state: “[The study used] established DNA barcoding technology.” Lot numbers for the tested products are provided, but no further study details are provided.
As reported by NutraIngredients-USA in 2013, DNA barcoding offers a lot of potential for botanical testing, and is incredibly reliable, but only when performed on appropriate material.
However, botanical extracts are particularly problematic because, while some extracts may contain DNA, it is often of low quality or degraded to a point that makes it impossible to perform proper authentication, explained Stefan Gafner, PhD, Chief Science Officer at the American Botanical Council. “Other processes, like extensive heat treatment, or submission of plant material to UV light also impact the quality and may lead to erroneous results using DNA methods,” he added.
Click on the following link to read our article, 10 questions we need answered regarding the NY AG’s botanical action
GNC disagrees but will comply
In a statement released from GNC, the retailer said: "We stand behind the quality, purity and potency of all ingredients listed on the labels of our private label products. The DNA barcoding technology employed on behalf of the Attorney General in testing our products has not been approved by the US Pharmacopeia and may not be appropriate for the testing of these herbal products.
"We test all of our products using validated and widely used testing methods, including those approved by US & British governing bodies. While standing firmly behind the quality, purity and potency of all ingredients listed on the labels of GNC private label products, including the GNC Herbal Plus line of products, GNC Holdings, Inc. today announced that it will voluntarily comply with the New York State Attorney General’s letter of February 2 by temporarily removing from our stores in New York the product lots cited in the letter."
GNC added that it will provide the AG's staff with a reasonable opportunity to review its full and robust response to its questions on, among other things, the standards and procedures GNC follows in authenticating the content of the GNC Herbal Plus products cited in the letter, including finished products testing results based on validated testing protocols.
"GNC is confident that its response will demonstrate that the five products in question are fully compliant, safe and properly labeled," said the company. "GNC is hopeful that the Attorney General’s staff will promptly reach the same conclusion."
The company said it expects to make these products available again to its customers in New York State after providing the State a reasonable time for review.
The Company also made these additional points:
• GNC tests all of its products using validated and widely used testing methods, including those approved by governing bodies like the United States Pharmacopeia and the British Pharmacopeia.
• GNC Herbal Plus products meet all federal regulatory standards as monitored by the Food and Drug Administration, our primary federal regulator. And there are no adverse event reports concerning these products.
• The DNA barcoding technology employed on behalf of the Attorney General’s office in testing GNC Herbal Plus products has not been approved by the United States Pharmacopeia and may not be appropriate for the testing of these herbal products. The Attorney General’s office has refused to provide the test data to GNC.