These reports include cases of accidental misidentification of botanical materials due to human error, but also cases of intentional adulteration (also referred to as economically-motivated adulteration), where raw materials are substituted or diluted with undisclosed lower-quality ingredients for financial gain of the seller. This poses a significant challenge to the global botanical medicine marketplace and, in some cases, impacts consumer safety.
The chemically complex nature of herbs and botanically-derived ingredients calls for unique quality control processes by suppliers, manufacturers, and producers of herbal products. One of the universal regulatory requirements in industrialised nations around the world is the appropriate testing for identity and authenticity of botanical materials that are to be used in consumer products. New analytical methods have improved the ability to establish the identity of plant-based ingredients and characterise their composition to aid in the detection of adulteration. At the same time, unscrupulous manufacturers and suppliers have succeeded in finding ways to deceive a potential buyer by providing botanical ingredients that appear to comply with standardisation requirements for specific marker/active compounds but take advantage of the lack of specificity of tests used to measure them. Examples include, for example, the addition of food dyes to St. John’s wort (Hypericum perforatum) extracts to enhance the UV/Vis absorption at the wavelength used to determine hypericin contents, the dilution of saw palmetto (Serenoa repens) extracts with undeclared vegetable oils or fatty acids from animal sources, or the addition of rutin- or quercetin-rich materials from extraneous sources to comply with the required contents for total flavonoids in ginkgo (Ginkgo biloba) extracts.
Reviews on adulteration of specific botanical ingredients are currently being compiled in a series of reports by an independent consortium of nonprofit organisations comprising the American Botanical Council (ABC), the American Herbal Pharmacopoeia (AHP), and the National Center for Natural Product Research (NCNPR) at the University of Mississippi. The ABC-AHP-NCNPR Botanical Adulterants Prevention Program is an international educational program that has been supported and endorsed by over 200 botanical industry companies, third-party analytical laboratories, manufacturers of analytical equipment, nonprofit professional organisations, trade associations, research centres, and others. To date, the Program has published 38 peer-reviewed documents, including a review of the history of adulteration and 20 papers summarising the evidence for adulteration of specific botanical ingredients. The Program has issued five Laboratory Guidance Documents in which all available analytical methods on botanicals and extracts in categories that are known to be adulterated are reviewed and evaluated for their ability to detect the suspected adulteration. Information on adulteration of essential oils has also been published, as well as a quarterly newsletter on global research and regulation on adulterants. All publications are freely available on the Program’s website here.