Editor's Note: This article was published as a guest article on Oct. 29, 2013 at NutraIngredients-usa.com. It is being reprinted with their permission as a courtesy to AHPA members.

Former FDA inspector discusses ID verification regulations, methodologies

Tamika Cathey, a former Food and Drug Administration (FDA) inspector and current independent regulatory consultant at EAS Consulting Group, discusses identity verification regulations and methodologies with the American Herbal Products Association (AHPA). 
Cathey and 15 other industry experts will discuss botanical identity verification regulations, methodologies, and technologies at the AHPA Botanical Congress being held Saturday, Nov. 16, at SupplySide West in Las Vegas.

AHPA: What responsibilities do manufacturers have when it comes to verifying the identity of ingredients?

Tamika Cathey: The manufacturer has the responsibility to verify the identity of any dietary ingredient by at least one appropriate test or examination per 21 CFR 111.75 (a)(1). In some cases, a single test or examination may be all that is required, but other cases may require conducting more than one test or examination.

For non-dietary ingredients (i.e., components), the manufacturer has the responsibility to conduct the appropriate test or examination or rely on a Certificate of Analysis (C of A) from the supplier per 21 CFR 111.75 (a)(2) contingent on the following:

• The manufacturer establishes the reliability of the C of A through confirmation testing.* The C of A includes description of the test or examination methods used, as well as their limits and actual results.
• The manufacturer qualifies the supplier with documentation of how the supplier was audited/qualified. Quality control personnel reviews and approves the documentation, noting the basis for qualification or requalification of the supplier.
• The manufacturer periodically reconfirms the supplier's C of A.

AHPA: Are there any identification verification responsibilities specific to botanicals?
TC: Manufacturers are 100 percent responsible for the identification of the botanical ingredients, using scientifically valid methods for authentication. The manufacturer also has to ensure that valid method is appropriate for the intended purposes (i.e., whole herb versus powder). The manufacturer should exercise due diligence to know its suppliers and the supply chain to help determine appropriate confirmation testing of the botanical ingredient. A verified botanical reference standard such as the American Herbal Pharmacopoeia is also critical in the identification verification process.

In the case of individual botanicals not in whole form (e.g., powder or extract), confirming the botanical identity can be

a challenge. It becomes even more difficult with botanical blends in a dietary supplement. Distinguishing key marker compounds can be almost impossible if ingredients contain the same marker from closely related species. In extracts, small trace amounts can also be hard to detect.

Manufacturers should focus on identifying the blend as a whole rather than each ingredient once it is a blended finished product.

AHPA: What are some strengths and weaknesses of the verification technologies currently available?

TC: Chemical and molecular methods, such as high performance liquid chromatography (HPLC), can provide good "indicators" of identity if known conditions (e.g., marker compounds) are met. Results are fairly rapid due to automation capabilities and sensitivity to some known marker compounds. However, these methods often exhibit limitations when attempting to differentiate closely related species, which becomes an issue when a finished product blends two or more closely related botanical ingredients, when dirt and/or insects are present, or when trying to distinguish different plant parts that share similar composition.

Macroscopic and organoleptic examinations are among the most useful and appropriate tests because the unique identifying features of the botanical ingredients (whole plant parts) are intact and readily distinguishable.

AHPA: Are certain tests more effective for verifying identity in different forms-whole versus powder versus extract?

TC: Yes, certain technologies are more useful depending on the form of the ingredient. For example: •Thin layer chromatography (TLC) and high performance thin layer chromatography (HPTLC) are good for identifying botanical ingredients in a single test run versus HPLC. This is also an appropriate test of botanical extracts (via constituents).

• Macroscopic exams are very good at identifying botanical ingredients in whole parts/plant parts (stems, leaves, roots, etc.) because you distinguish the "true" identity of an ingredient. Once botanicals are highly processed (powders, extracts, etc.), it can become very difficult or impossible to verify identity using this method.

• Microscopic exams are good for highly refined materials identification testing and common botanical ingredients in powered form. They are not appropriate to identify botanical extracts.
• Fourier transform infrared (FTIR) and near infrared spectroscopy (NIR) are good for highly refined materials, but not appropriate for botanicals. These are often inappropriately used as a "one size fits all" instrument. 
• HPLC/gas chromatography/Spectrophotometer can be used for detecting different key marker compounds, but is limited if the different ingredients contain the same marker or if markers are widely distributed in nature, as is the case with botanicals. These can also be used for verifying the identity of fish oils in finished products. 
• Organoleptic can be a very good identification test if an experienced, trained individual such as a botanist is involved, but it should not be used as a standalone test. This approach has limitations associated with visual examination confirmation for powdered and processed botanical ingredients.
• Inductively coupled plasma mass spectrometry (ICP-MS) is good for heavy metal detection and mineral detection.

AHPA: Given all the technology available, is there still a role for organoleptic analysis?

TC: Yes, organoleptic analysis is still very effective in identifying whole form plant (root, stems, leaves, fruit, etc.) by trained individuals who can recognize the ingredient (e.g. goldenseal) and its common adulterants. It can also be a good indicator that something is wrong with the ingredient per expected sensory evaluation, such as smell, for processed ingredients and/or finished product. There are differentiation limitations associated with chemical and molecular methods in regard to identification verification. These would make the organoleptic evaluation a more appropriate choice, but it should be used in conjunction with chemical/molecular methods.