Cannabis Flower Testing Shows THC Potency Widely Inflated In Colorado

Most Colorado cannabis flower products are mislabeled with inflated THC levels, according to a study published this month in Scientific Reports.

The study, conducted by researchers at the University of Colorado Boulder, anonymously sampled hundreds of different cannabis products from 52 state-licensed retailers and tested the samples for THC content. Of the 178 flower samples, over half — 56.7% — were found to have “significantly lower” THC potency than their labels suggested. The study authors also found that while product labels for cannabis concentrates “met the accuracy threshold for THC content,” the 99 sampled products had “lower observed THC content compared to labeled values.”

The study suggests that the practice of “lab shopping” — where cannabis operators select testing labs based on which one yields the most favorable results, from a marketing perspective — is still prevalent in Colorado.

Greg Giordano, Senior Professional Research Assistant and one of the study’s authors, told CPR News that accurate labeling is a key part of having a regulated cannabis market.

“It’s important that we have accurate cannabis product labels so people who do that kind of research — looking at risks, potential risks — that they know what’s in the product.” — Giordano, via CPR

Regulators with the Colorado Marijuana Enforcement Division (MED) said they “look forward to an opportunity to discuss the findings of the study in a public forum with the licensee and other stakeholders in the near future,” according to the report.