Marijuana Edibles Need Accurate Labeling

As any behavioral scientist will tell you, their studies often stem from their own personal questions and experiences. For Dr. Ryan Vandrey, an Associate Professor of Psychiatry and Behavioral Sciences at Johns Hopkins, his question for his latest investigation came after visits to marijuana dispensaries.

"There was one person who I talked to for about a half-hour, and he couldn't tell me how many different people were part of his co-op," said Vandrey. "He didn't seem to know or understand if there was any quality control in anything he was selling."

And so, Vandrey and his fellow scientists set about answering the question: How accurate are labels on medicinal marijuana edibles?

Vandrey and company examined samples from three different cities (Los Angeles, San Francisco, Seattle) in two different states (California, Washington) that allow for medical marijuana prescriptions. They bought a large sample of different edibles, from baked goods, to candies, to drinks. They then compared the amount of THC -- the chemical in marijuana that gives it the various psychoactive properties -- listed on the label to the amount of THC that was actually in the product when tested.

When they compared all the data, they found that:

This is not good.

"Once Colorado and Washington passed regulations for non-medical use, they had very strict regulations in terms of testing requirements," said Vandrey. "But the same standards weren't there for the medical product of sales. In my mind, that's backwards."

If you're providing somebody with what is, at least by definition according to state laws, a medicinal product, then there should be reliable and consistent dosing. Consider the effects: "If you have products that contain less drug than what they advertise, then you have a situation where individuals are not getting the medication they believe they're taking," Vandrey said.

For example, if you're taking treatment for, multiple sclerosis and you ingest less than the amount you've been prescribed, there could be adverse consequences. Perhaps more worrisome is what happens if you take a higher dose than you expected.

"Side effects vary from person to person, but it can cause vomit, acute panic reaction, paranoia, and in extreme circumstances you can have significant cardiovascular responses, or go into an acute psychotic state," Vandrey said. "It can also impair your ability to get through your day-to-day function, to drive, to take care of your family, to work."

The only thing that frustrated and worried consumers can do is ask the dispensary for a certificate of analysis for the product they want to consume. Even then, the fact that there's no agency assuring the accuracy of the analysis means that the information is to be taken with a grain of salt. (If you make a batch of 100 brownies, and test three of them for THC levels, the results of that test doesn't mean the other 97 will have the same content.)

Vandrey hopes that the study spotlights the fact that this industry (which, again, is used for medicinal purposes in the eyes of California law) should be regulated. And the first step in regulation is to have much fewer products on the shelves of dispensaries.

"In my mind, the solution is that the edible oral cannabis products should be constrained to three or four product types," Vandrey said. "And there should be manufacturing standards developed for what those types are, and then you move forward with regulated products that have oversight."