537 - Dazed and Confused: Variability in Reported and Measured THC Content in Cannabis Edibles

Publication Number: 537.4074

Laura Lee Beneke, University of Mississippi School of Medicine, Jackson, MS, United States; John B. Benton, University of Mississippi School of Medicine, Jackson, MS, United States; Patrick B.. Kyle, University of Mississippi Medical Center, Jackson, MS, United States; Matthew W. Maready, University of Mississippi School of Medicine, Jackson, MS, United States

Background: Cannabis plant and cannabinoid derivatives are widely used. Its principal metabolites are Δ9-tetrahydracannabinol (THC) and cannabidiol (CBD), with THC being psychoactive. Upon legalization of THC and CBD products, producers found loopholes to increase THC content in CBD products. Since legalization of medical marijuana in Mississippi in 2022, there has been an increase in admissions for intoxicated young children after ingestion of THC edibles. The level of intoxication and duration of symptoms has led to concern surrounding accuracy of package dosing of these products. The purpose of this study is to compare package reported and lab measured THC content in cannabis edibles.

Objective: The primary objective of the study was to compare the reported and measured level of THC in edibles from the area. The study authors hypothesize that the actual measured levels will be higher than those reported on packaging.

Design/Methods: 3 samples from each of 13 packages of THC edibles were tested. The extraction for each sample was the same, based on a previous study. A gummy, or a 50mg piece, was dissolved in water of a specified amount based on THC content. 10µL of gummy solution was added to 990µL of water in a 1:100 dilution. 400µL of deuterium solution was then added, followed by 1mL of acetonitrile. The new solution was vortexed for 30s. Next, the solution was filtered via solid phase extraction. 100µL of the solution was then added to 900µL of 0.1% formic acid. Finally, samples were placed in a liquid chromatograph-mass spectrometer (LC-MS) for analysis of THC.

Results: In most products, lab measured THC values were higher than package labeling. Some products (Wedding Cake, Durban Poison) differed by hundreds of milligrams per gummy. Because the mass spectrometer was only calibrated to detect Δ9-THC and CBD, other similarly-sized psychoactive cannabis metabolites (eg. Δ8-THC) could have been detected and interpreted as Δ9-THC. This is a potential reason the spectrometer reported Δ9-THC values to be much higher than labeled values. We believe that several similar metabolites were potentially added to these products.

Conclusion(s): Most products studied showed significantly higher levels of THC metabolites than was reported on their packaging. This may be due to actual higher levels of Δ9-THC or due to the addition of other psychoactive compounds. More research could measure levels of each specific metabolite to better understand the complete chemical makeup of these products. This research should guide regulatory efforts and increase product transparency in order to prevent accidental overdose in small children.

THC Gummies Tested
These are the products tested in the study. Some of the products were obtained from medical dispensaries while others were purchased at local stores.

Measured v Reported THC Levels in Edibles
Side-by-side comparisons show most products tested had substantially higher levels of Δ9-THC per gummy than what was reported on the packaging labels. Due to molecular similarity, some of this may be related to the unreported addition of similar psychoactive compounds. This loophole has been identified by other reports as a way to increase the psychoactive effect of gummies despite efforts to regulate Δ9-THC quantity.

THC Gummies Tested
These are the products tested in the study. Some of the products were obtained from medical dispensaries while others were purchased at local stores.

Measured v Reported THC Levels in Edibles
Side-by-side comparisons show most products tested had substantially higher levels of Δ9-THC per gummy than what was reported on the packaging labels. Due to molecular similarity, some of this may be related to the unreported addition of similar psychoactive compounds. This loophole has been identified by other reports as a way to increase the psychoactive effect of gummies despite efforts to regulate Δ9-THC quantity.