Bad actors to blame for inaccurate cannabis labels? Not so fast

Susan Audino

All cannabis consumers have a right to confidently know the contents of the products they purchase.

But ongoing random, observational and longitudinal studies have demonstrated that many product labels in the cannabis sector don’t concur with independent analytical test results.

Many in the cannabis industry have come to regard some as “bad players” when labels and test results don’t match. Reality may be more complicated.

Look at a recent cohort study published in JAMA Network, an open-access medical journal published by the American Medical Association, in which cannabinoid metabolites were not always present as expected.

The piece spotlighted cannabis product label claims that were not supported by independent laboratory tests for cannabinoids in urine.

Specifically, 97 participants contributed a combined 256 urine samples at five collection times spread over 38 months ending in August 2020.

Each participant classified his or her commercial cannabis products as “THC-dominant, CBD-dominant, or approximately equal CBD and THC.”

Results showed an absence of CBD metabolites in 30.3% of samples where participants reported using “CBD-dominant” products.

There were an absence of CBD metabolites in 37% of samples of products classified as containing approximately equal parts CBD and THC.

With respect to THC metabolites, none were detected in 10.9% samples collected after using THC-dominant products, and none were detected in 35.2% of samples where participants used approximately equal CBD-THC products.

Further, nearly 20% of participants’ samples contained no measurable CBD when using vape cartridges, even though vaping was reportedly the most common delivery mechanism.

These results are not surprising in light of the absence of measurement or labeling standards in the cannabis marketplace.

A 2017 research letter issued by JAMA raised similar concerns. Researchers tested 84 CBD products purchased online. They found that 26% contained less CBD than claimed.

In 2014, the U.S Food and Drug Administration tested 23 products and determined that CBD concentration was consistent with only 35% of the respective label claims.

A subsequent FDA study in 2020 evaluated 147 products, 102 of which made claims to specific CBD amounts. Results indicated that:

  • 18% contained less than 80% of the claim.
  • 45% products were within 20% of the claim.
  • 37% contained more than 120% of CBD purported on the label claim.

 Bad players to blame?

The knee-jerk reaction to these kinds of studies is to assume the product manufacturer with inaccurate product labels is a “bad player” consciously intending to defraud or cheat the consumer.

Perhaps it would be prudent to consider less malevolent yet equally plausible potential root causes to these discrepancies.

First, we need to keep in mind that all studies, though well-intentioned, have included relatively small numbers and types of products in their testing protocols.

Larger sample sizes are on the horizon. Last year, the FDA initiated a more exhaustive sampling plan and long-term study.

More to the point, product manufacturers are usually required to submit their cannabis products for analysis by independent third-party testing labs, which introduces another wrinkle.

Lab discrepancies

Cannabis-testing laboratories are disadvantaged by the lack of published multi-laboratory-validated standard test methods, which are available to nearly every other agricultural commodity destined for human or pet consumption.

Consequently, each laboratory is left to develop its own test methods.

As we know, the creation of marijuana- and hemp-infused products is limited only by one’s imagination as the industry lays claim to products like foods, dietary supplements and personal-care items consumed in different ways.

Not all laboratories take the time to thoroughly and empirically evaluate each matrix-type during their method validation or subsequent matrix-extension studies.

Matrix complexity and interferences are critical features that should be thoroughly evaluated and empirically defended in all sample preparation methods.

Finally, the laboratory also must ensure a solid customer base.

Too often, customers who receive unexpected or undesirable test will take their business to competitor laboratories that may perform substandard work to provide acceptable test results.

Sampling confusion

Perhaps the most egregious deficit of every cannabis-testing laboratory is bulk-sampling practices.

The economy of the cannabis material is so high that regulators prohibit large samples from the lot or batch, often forcing laboratories to make inferences on lots of 50 or more pounds using only 20 to 30 grams of a highly complex material.

That can easily cause discrepancy between two test values of the same material.

Cannabis-testing laboratories are not always the root cause for discrepant product label claims.

All too often laboratories must develop their test methods to meet analytical specifications imposed by regulatory bodies that don’t understand analytical chemistry or laboratory practices.

When this occurs, any new or existing laboratory is disadvantaged before it develops its first method.

Well-intentioned or not, cannabis regulatory bodies are often integral to laboratory failures by establishing specifications that are unrealistic and susceptible to diverse interpretations.

Patchwork problems

Inaccurate product labels are a problem for each and every consumer.

Until well-established, multi-laboratory-validated methods become standard practice, we must cautiously evaluate before judging article headlines that a label claim was not substantiated by laboratory testing.

As of this writing, there is no way to definitively know which testing method is superior or most appropriate. Only equivalent methods and instruments can provide a more accurate comparison of test results.

The lack of federal (versus state-by-state) regulation makes discrepant content and label claims worse.

Unless federal regulation also includes a suite of federal standard laboratory test methods and reasonable bulk- sample size, the industry is likely to continue along its current path of product uncertainty and questionable product label claims, thereby continuing to compromise consumer safety.

Finally, and most important, regulatory and scientific communities must work together to develop and implement mechanisms to discern the bad players from disadvantaged and well-intentioned businesses in the cannabis industry.

Punishment should be delivered to the former, and resources should be provided to the latter. This will drive social equity, scientific integrity and consumer confidence.

Susan Audino, who holds a doctorate in chemistry, is a chemistry consultant and instructor for the American Association for Laboratory Accreditation. She is based in Ohio.