The cannabis you buy may not get you as high as you hoped.
The study results show a lack of regulation in the country’s burgeoning cannabis industry and suggest that many buyers may be deceived into believing their purchase will have a stronger concentration of THC, the psychoactive compound responsible for the euphoric “high” that weed provides. Researchers say it is the first peer-reviewed study to experimentally examine the effectiveness of commercially available cannabis.
“I can’t believe what’s on the label,” said Mitt McGlaughlin, one of the study’s authors and a professor of biological sciences at the University of Northern Colorado. “We don’t have enough information for consumers about whether or not you can trust what is being produced.”
To conduct the study, researchers purchased 23 different cannabis flower samples from 10 dispensaries in Denver, Fort Collins and Garden City, Colo., and tested each sample to measure the concentration of THC, which stands for Delta-9-tetrahydrocannabinol.
In 18 of the 23 samples that bore names including Sour Amnesia, Danky Kong, and Colombian Gold ’72, researchers found potency levels lower than listed on the labels. Depending on the bag tested, some products contained 40 to 50 percent less THC than the label promised. The amount of THC detected in the lab was, on average, 23 percent less than the amount listed on hemp bags.
Five samples contained THC levels either within the range or close to those listed on the labels.
The study authors concluded, “These findings demonstrate that consumers often purchase cannabis that has a significantly lower THC potency than advertised.”
How is cannabis regulated?
Recreational cannabis is legal in 21 states and in D.C., and generates billions of dollars in annual sales. But researchers say there is not enough oversight of the dose of THC a person might get when purchasing marijuana, whether smoking, vaporizing, or ingesting it. One reason for the lack of oversight is that cannabis is still illegal under federal law, which means that standards regarding retail and medical use vary by state.
“We have a patchwork of rules and regulations within each state,” McGlaughlin said. “It’s really hard to do that on a country-by-country basis.”
Just as breweries list the percentage of alcohol in beer bottles, marijuana dispensaries often label bags of cannabis with THC content. Researchers say that companies that grow cannabis usually send samples to outside labs to measure the amount of THC in the plant. Often, the higher the concentration of THC, the higher the price.
This pricing dynamic has incentivized companies to grow, sell and market cannabis with higher concentrations of THC, says Anna Schwab, lead author of the study, which she conducted as a doctoral student at the University of Northern Colorado.
“It’s just kind of a mess right now,” said Schwab, director of research and development at a cannabis farm in New Jersey. “And really, the people on the short end of that stick are the consumers.”
How much THC is in recreational marijuana?
People who use marijuana regularly for pain or insomnia, for example, might try measuring their THC intake, said Schwab, who is also a lecturer at the University of Colorado at Boulder. Schwab said it’s hard for consumers to accurately judge when a label doesn’t match what they bought.
“They don’t get what they paid for,” Schwab said. “This is not just a Colorado issue; this is a national issue.”
In February, a patient with a medical marijuana license in Arkansas sued a cannabis testing lab and a cannabis farm for allegedly exaggerating allegations about The amount of THC in marijuana that a person has purchased. Two people filed a similar lawsuit in California in October, accusing a company of falsely advertising pre-rolled joints.
Consumers can’t always trust what’s on the labels of these products, said Judy Gilman, director of neuroscience at the Center for Addiction Medicine at Massachusetts General Hospital. In a clinical trial published in 2021, Gilman said that people who thought they were taking CBD, another compound in cannabis that doesn’t cause the same high, were actually inadvertently taking a cannabis product that contained THC.
“That was a really scary experience for them,” said Gilman, who was not involved in the Colorado study. “You can’t always trust what’s on the label.”
Schwabe said she first noticed the discrepancy in reported versus actual THC while she was conducting a separate study on the scents of different strains of weed. Additional samples were collected for the new research.
Schwabe and McGlaughlin sent cannabis samples to a private lab. In the lab, McGlaughlin said, researchers dissolved cannabis buds in a solution and ran the resulting liquid through a chromatography machine that separated all components of the plant according to molecular weight. By doing this, they were able to determine the concentration of THC.
The amount of THC found in different parts of the cannabis plant can vary. Often, as you travel from the top of the plant to the lower ends, the concentration of THC will drop, say the researchers. Schwabe said that advances in cannabis cultivation and growth in recent decades have led to an overall increase in the amount of THC in the weed. But she said she did not think the increase was “as exaggerated as we think”.
Researchers say THC in the cannabis bud can degrade over time, especially if the weed is not stored properly. But, when THC breaks down, it converts to cannabinol, which, according to the researchers, “was not observed in significant quantities in the samples used in the study, indicating that the lower potency in the observed versus reported values was not due to age or poor conditions.” storage.”