Is the ‘gold standard’ in laboratory quality assurance really golden?

cannabis testing, Is the ‘gold standard’ in laboratory quality assurance really golden?

Susan Audino

Editor’s note: This column originally appeared in the MJBizScience newsletter. Simply sign up here to get it fresh to your inbox each month. Susan Audino holds a doctorate in chemistry and is a chemistry consultant and instructor for the American Association for Laboratory Accreditation.

Laboratories cannot reasonably ascertain a cannabis product’s composition with 100% certainty.

Many states with legal cannabis and cannabis-derived products require products to be tested by independent third-party testing laboratories.

The labs are tasked with ensuring no product violates the regulatory requirements and specifications for contaminants—and that products meet label requirements.

Most states require laboratories to be accredited to ISO/IEC 17025:2017, long recognized as the “gold standard” for testing and calibration laboratory quality assurance.

The critical element of a laboratory’s accreditation is the objective third-party verification of the their technical competence. More than 60,000 laboratories worldwide have attained ISO/IEC 17025 accreditation. This is not a new standard, nor was it developed for the cannabis industry.

All laboratories should aspire to earn third-party accreditation. But this achievement is not a guarantee they employ good science.

Reading between the lines

Accreditation means that the laboratory is technically competent to perform a specified scope of activities. The term “technically competent” doesn’t necessarily mean that the lab is implementing the best possible technical program.

I recently came across a guide to understanding the cannabis certificate of analysis (COA) and was sorely disheartened to read “only an accredited laboratory is able to give precise results,” and that the lab’s COA “provides an accurate report and gives you 100% accurate information about the product composition.”

These statements are misleading.

There are exceptionally good laboratories in all industries that are more than capable of providing precise test results; this claim is not limited to accredited labs.
Similarly, cannabis and hemp testing labs are encumbered by the matrix’s complexities to give “100% accurate information” about any sample—not to mention contributions from measurement error, bias and uncertainty.

As the arsenal of standard test methods continues to evolve, laboratories must develop at least some of their own test methods.

ISO/IEC 17025 accreditation does not require any laboratory to use specific instruments or materials, nor does it require they implement the most empirically sound methodology. The standard requires only that the laboratory demonstrate technical competence for a specified scope of activities.

Know your limits

All labs should fully embrace the intent of the foundation in quality structured by ISO/IEC 17025. However, all interested parties must understand the limitations of accreditation.

First and foremost, even if a lab has attained accreditation, there is no guarantee that it consistently implements a quality-assurance program.

Second, laboratory customers must share the responsibility to ensure the laboratory is using the most technically sound method to meet their needs. That is, customers must discuss their specific needs with laboratory candidates, and the laboratories should candidly disclose any limitations of their own technical programs — especially if the program does not meet the needs of the customer.

Finally, all laboratories should seek the most rigorous scientific program—even when not required by the standard.