Levels of THC Incorrectly Labeled on Most Edible Marijuana Products: Study

Most edible marijuana products incorrectly list their levels of THC, the main psychoactive ingredient, a new study finds.

The study analyzed 75 edible marijuana products sold in Seattle, San Francisco and Los Angeles, according to The New York Times. Only 17 percent of the products correctly described their levels of THC. Researchers found 60 percent of the products had less THC than the packages stated, and 23 percent had more THC than advertised.

The study is published in JAMA.

Medical marijuana products with more THC than advertised could cause overdosing side effects, including extreme anxiety and psychotic reactions, study lead author Ryan Vandrey of the Johns Hopkins University School of Medicine noted in a news release. “If this study is representative of the medical cannabis market, we may have hundreds of thousands of patients buying cannabis products that are mislabeled,” Vandrey said.

One product had only three milligrams of THC, although the label claimed it had 108, according to Vandrey. “The point is not to say, ‘Hey, X medical marijuana company, you’re bad,’” he told the newspaper. The more serious problem is that “we don’t have the kind of quality assurance for edibles that we have for any other medicine.”

The chance of buying an edible marijuana product with more THC than labeled was higher in Los Angeles, while products that had less THC than advertised were more common in Seattle.

The study also analyzed products for cannabidiol, or CBD, a nonpsychoactive ingredient of marijuana that is being studied in purified form as a possible treatment for children with severe epilepsy. The researchers found 44 products had detectable CBD levels, although only 13 listed it on the label. Of those products, nine had less CBS than labeled, and four had more.