Typical means of adulteration within the supplements industry include economically motivated substitution of a more expensive ingredient with a less expensive ingredient¹ and pharmaceutical adulteration where an active drug is included in an alleged botanical supplement. In several instances, products with “natural” labels have had naturally sourced ingredients replaced with petrochemical-derived counterparts, often for the purpose of financial gain.

Quality control (QC) and quality assurance (QA) need to catch ingredient adulteration and prevent adulterated products from reaching the marketplace. Selecting appropriate analytical methods to detect adulteration is a key part of the solution. Rigorous and routine QC procedures that incorporate carbon-14 technology will ultimately allow for the distinction between biomass-derived and petrochemical-derived ingredients in supplements, authenticating natural source claims.

How to detect supplement ingredient adulteration

Products sourced only from plants, animals or microbiological materials tend to be more expensive in comparison to their petroleum-derived counterparts. This may lead manufacturers or distributors to fraudulently substitute biomass material with cheaper, petrochemical-derived ingredients and mislabel the counterfeit ingredients as naturally sourced.²

Dietary supplements are prone to adulteration as aspirations for economic gain cloud the integrity of industry stakeholders.³ By implementing procedures to authenticate ingredients, QC departments can verify the source of ingredients to combat economic adulteration.

An example of such method is carbon-14 testing, which analyzes product ingredients to differentiate between naturally derived and petrochemically derived ingredients, allowing for detection of fraudulently labeled “natural” supplements. Carbon-14 testing can measure the exact percentage of carbon in a product that comes from biomass-based sources. All material comprised of biomass sources contains a known amount of the isotope carbon-14, whereas material which was alive over 50,000 years ago such as petroleum has no carbon-14. Carbon-14 testing of products which are 100% naturally sourced will, therefore, report a result of 100% biobased after undergoing the analysis. However, products that are only partially comprised of biomass-derived material will report a result that ranges between 0% and 100% biobased.⁴

Carbon-14 testing for natural products is an established method according to standards such as ASTM International D6866 and International Organization for Standardization (ISO) 16620-2. These standards were developed to determine the biobased content of solid, liquid and gaseous material using carbon-14 analysis, applicable to several products including supplements, flavors, fragrances, foods and beverages.^5,6

Adulteration of supplement ingredients

Botanical supplements are still vulnerable to adulteration,^7,8 even though they are regulated by FDA under the Federal Food, Drug and Cosmetic Act (FD&C), which protects consumers from deceptive labels and prohibits marketing of misbranded products.

Turmeric is growing in popularity due to its widespread use, however, alongside this increasing demand for turmeric is the growing potential for ingredient adulteration. The risk of adulteration of turmeric may be increased due to the high cost of the ingredient. Curcumin is a main component in turmeric dietary supplements, and because of the low cost associated with petroleum-derived synthetic curcumin, replacing natural-sourced curcumin with the cheaper petroleum-based alternative offers a significant financial incentive. Although analytical methods such as high-performance liquid chromatography (HPLC) can show a characteristic fingerprint to identify and distinguish between Curcuma species, carbon-14 analysis can identify if there are petrochemical compounds present in a botanical supplement.⁹

As with turmeric, adulteration of several other natural-sourced botanical extracts with petrochemical synthetics is widespread, especially amid relatively high-cost materials. Therefore, with the potential for economic adulteration on the table, carbon-14 testing is a necessary tool when it comes to distinguishing between biomass-derived and petrochemical-derived ingredients and when authenticating “natural” label claims.

The rising consumer demand for naturally sourced supplements highlights the need to test botanical ingredients for potential adulteration.3 Within the supplement and natural products industry, cases of adulteration are often due to intentions of economic gain, causing some companies to mislabel petrochemical-derived product ingredients as natural. QC departments are aware of the potential for ingredient adulteration and often turn to analytical methods like carbon-14 testing to address this industry challenge. 

Haley Gershon is marketing specialist at Beta Analytic.

References

1. Cohen P. “The FDA and Adulterated Supplements—Dereliction of Duty. JAMA Netw Open. 2018 Oct 5;1(6):e183329. DOi: 10.1001/jamanetworkopen.2018.3329.

2. Boren K et al. “Detecting essential oil adulteration.” J Environ Anal Chem 2015, 2:132. DOI: 10.4172/2380-2391.1000132

3. Wheatley V, Spink J. “Defining the Public Health Threat of Dietary Supplement Fraud.” Comprehensive Reviews in Food Science and Food Safety. 15 October 2013. DOI: 10.1111/1541-4337.12033

4. American Chemical Society National Historic Chemical Landmarks. “Discovery of Radiocarbon Dating.” American Chemical Society. 10 October 2016.

5. ASTM International. ASTM D6866 - 18, Standard Test Methods for Determining the Biobased Content of Solid, Liquid, and Gaseous Samples Using Radiocarbon Analysis. 2018.

6. International Organization for Standardization. ISO 16620-2:2015, Plastics -- Biobased content -- Part 2: Determination of biobased carbon content. April 2015.

7. Shipkowski K et al. “Naturally complex: Perspectives and challenges associated with Botanical Dietary Supplement Safety assessment.” Food Chem Toxicol. 2018 Aug;118:963-971. DOI: 10.1016/j.fct.2018.04.007.

8. U.S. Food & Drug Administration. Labeling Requirements - Misbranding. 27 October 2018.

9. Bejar E. “Turmeric (Curcuma longa) Root and Rhizome, and Root and Rhizome Extracts.” American Botanical Council. 2018 June 5.