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In the NoCo

Why a new CU study raises doubts about the accuracy of labels on cannabis products

Jonny Lisano, a researcher at the University of Colorado Boulder, stands in front of a bulletin board wearing a white polo shirt and a lanyard with a name tag around his neck. On the bulletin board behind his shoulder is some information regarding methodology and studies of cannabis on pain.
Courtesy of Jonny Lisano / CU Boulder
Jonny Lisano, a researcher at the University of Colorado Boulder, was part of a team that analyzed the accuracy of potency labels on cannabis products. The study shows the THC content shown on labels is often higher - or sometimes lower - than what's indicated on the label.

When we shop for food, the labels on our groceries give us guideposts, such as how much fiber, protein or fat is in that loaf of bread or jar of peanut butter.

But more than a decade after Colorado legalized recreational cannabis, the potency labeling on products at your local marijuana dispensary may be far less helpful – and less reliable.

A new study from the University of Colorado Boulder found that almost half of cannabis flower products sold at dispensaries across the state are inaccurately labeled. Researchers found that flower products often contain less – or more – of compounds like THC and CBD than indicated on the label.

The findings raise questions about quality control within cannabis companies, as well as how much consumers should trust these labels, especially when they buy higher-potency marijuana. The results of the study were published earlier this month in the journal Scientific Reports.

Erin O’Toole spoke with one of the CU researchers, Jonny Lisano, to learn more about the study and what it means for consumer trust.

For more cannabis coverage, check out In The NoCo’s recent conversations that explored how long-term marijuana use might impact memory and a study of cannabis’ potential as a treatment for cancer and its symptoms.

KUNC's In The NoCo is a daily slice of stories, news, people and issues. It's a window to the communities along the Colorado Rocky Mountains. The show brings context and insight to the stories of the day, often elevating unheard voices in the process. And because life in Northern Colorado is a balance of work and play, we celebrate the lighter side of things here, too.
As the host of KUNC’s new program and podcast In the NoCo, I work closely with our producers and reporters to bring context and diverse perspectives to the important issues of the day. Northern Colorado is such a diverse and growing region, brimming with history, culture, music, education, civic engagement, and amazing outdoor recreation. I love finding the stories and voices that reflect what makes NoCo such an extraordinary place to live.
Brad Turner is an executive producer in KUNC's newsroom. He manages the podcast team that makes In The NoCo, which also airs weekdays in Morning Edition and All Things Considered. His work as a podcaster and journalist has appeared on NPR's Weekend Edition, NPR Music, the PBS Newshour, Colorado Public Radio, MTV Online, the Denver Post, Boulder's Daily Camera, and the Longmont Times-Call.
Ariel Lavery grew up in Louisville, Colorado and has returned to the Front Range after spending over 25 years moving around the country. She co-created the podcast Middle of Everywhere for WKMS, Murray State University’s NPR member station, and won Public Media Journalism awards in every season she produced for Middle of Everywhere. Her most recent series project is "The Burn Scar", published with The Modern West podcast. In it, she chronicles two years of her family’s financial and emotional struggle following the loss of her childhood home in the Marshall Fire.