Doubt cast on accuracy of cannabis oil labels

Published on July 5, 2024 by David Wylie

Bottles of cannabis oil are shown. Photo: David Wylie/the oz.

The first ever study of accuracy on legal cannabis oil labels in Canada is casting serious doubt on whether they’re trustworthy.

Researchers from McMaster University randomly selected 30 products available through the Ontario Cannabis Store between November 2021 and January 2022.

“Our findings suggest that inaccurate labeling of cannabis oil products in the legal Canadian market is common, with most discrepancies due to labeling products with greater THC or CBD content than was present,” say researchers.

A key component of legalization is quality control, including cannabis labeling requirements that specify the allowable variance between labeled and actual amounts of THC and CBD in a commercial product.

While, federal cannabis regulations allow for variability for extracts at 15% above or below the product’s labeled amount, a new study shows significant errors even beyond that threshold.

“There were discrepancies between information on the OCS website regarding advertised amounts of THC and CBD and physical product labels for 10 of 30 oil products,” says the study summary posted on JAMA Network.

“We also found internal inconsistency, with five products labeled with discordant THC/CBD (denotes active cannabinoid content) and total THC/CBD (denotes cannabinoid content after product is heated for consumption) concentrations, which should be identical for extract type products. The product with the largest discrepancy was labeled as having 5 mg/g CBD but 26 mg/g total CBD.”

Overall, 12 products (40%) were outside the variability limit for THC and three products were outside the variability limit for CBD. Among 16 products that had a label amount of 2.5 mg/g THC or greater, seven products had amounts that were lower than what was labeled by more than 15%.

No products contained more THC than labeled at an amount that would be expected to have substantively different psychoactive effects. However, say researchers, given that many medical consumers obtain products from the non-medical market, one implication is inaccurate dosing.

“Altogether, these findings suggest a need for greater quality control in the Canadian legal cannabis market and undermine the assumption that a legal market is an assurance of accurate labeling,” they say.

Researchers note the sample size of 30 products is not representative of all available products in Ontario or Canadian markets.