Consumption of marijuana edibles rises amidst scarce research into their health impact

Read the Full Transcript

• Judy Woodruff:

  But first: The number of states where recreational pot is now legal is growing. It's up to 10 states and the District of Columbia.

  Many users are consuming marijuana edibles, instead of smoking the leaf. But the research on the effects of edibles is scarce.

  From Rocky Mountain PBS in Denver, Lori Jane Gliha explores the potential link between marijuana edibles and psychosis.

• Man:

  A man accused of murdering his wife while she was on the phone calling 911.

• Woman:

  She said her husband was hallucinating and was scaring their three small children.

• Lori Jane Gliha:

  In April 2014, Richard Kirk did the unthinkable. The father of three opened his family safe, retrieved his gun, and shot his wife in the head.

• Richard Kirk:

  Who else is interested in the truth?

• Man:

  Me. It's you and me right here.

• Richard Kirk:

  So far, nobody has been interested in the truth.

• Lori Jane Gliha:

  This footage from questioning at the police station shows a confused Kirk not long after he pulled the trigger.

• Man:

  If you can't afford a lawyer, one will be appointed to you without cost to you before questioning. Do you understand each of these rights that I have read to you?

• Richard Kirk:

  I was kind of spaced out.

• Man:

  You want to go over them? We will go over them again.

• Richard Kirk:

  Yes, please.

• Man:

  Yes, please.

• Lori Jane Gliha:

  He blamed the murder on a marijuana-infused edible gummy, which at the time was newly legalized for recreational consumption in Colorado.

• Richard Kirk:

  That was the worst decision I ever made in my life.

• Lori Jane Gliha:

  This is the first interview Kirk has given. The prison wouldn't permit video cameras inside, but we were allowed to record audio.

• Richard Kirk:

  I know, without any doubt, that if I didn't eat that marijuana, my wife and family would still be together today. I know that with a certainty.

• Lori Jane Gliha:

  It is the first time since the murder in 2014 that he has spoken publicly. And despite a history of marital troubles, financial issues, and allegations he had a short temper, he still insists the marijuana edible made him do it.

• Richard Kirk:

  I didn't know it was my wife. I thought it was somebody else, I guess. That's the only way I could have done it. I never, ever once thought about even hurting my wife or pushing her or anything.

• Lori Jane Gliha:

  Whether you believe his story or not, Colorado regulators did make significant changes after that incident, by restricting serving sizes, limiting the psychoactive ingredient THC in each serving to 10 milligrams, with no more than 100 milligrams in a single package.

  And one marijuana researcher says he has new evidence linking edibles to psychiatric complications in the emergency room.

• Dr. Andrew Monte:

  There seem to be a disproportionate number of visits associated with edible cannabis products compared to other products.

• Lori Jane Gliha:

  Dr. Andrew Monte sits on Colorado's Retail Marijuana Public Health Advisory Committee, and has been researching cannabis since 2009. He also worked as a paid consultant for Kirk's defense team.

• Dr. Andrew Monte:

  Not everybody that takes an edible agent is going to have hallucinations. Many, many people do take it and take it safely, and so we need to understand and respect that.

• Lori Jane Gliha:

  In his latest research, which is now undergoing a peer review, Monte tracked the 2,600 marijuana-attributable patient visits to the emergency department at UCHealth University of Colorado Hospital over the last five years.

  The number of emergency patients with marijuana-related symptoms who visited the hospital made up less than 1 percent of all visitors to the E.R. But Monte found, of those, medical events like hallucinations occurred at a greater rate for edible users when compared with patients who smoked the drug.

• Dr. Andrew Monte:

  Clearly, edibles seem to have a more severe toxicity than inhaled agents, and it seems that much of this is actually psychiatric in nature.

• Lori Jane Gliha:

  While Dr. Monte warns of the unpredictability of edibles, little research has been done on their effects. Pot proponents say consumers have been empowered to use them responsibly for years, with few problems.

• Brian Nowak:

  It's more about the education. Start low and go slow. I will even advise people, if they're really unsure, to cut one of those in half.

• Lori Jane Gliha:

  Brian Nowak is the general manager at the Simply Pure Dispensary in Denver Colorado.

• Brian Nowak:

  I understand the caution. I just think that now we really need to focus on the research and education, so that we can start basing things off of facts and science, rather than just this — being scared of a new industry.

• Lori Jane Gliha:

  There is no consistent method for tracking violent incidents linked to edibles. Our reporting found only a handful of cases across the country since 2014 that were so violent, they made the news.

  A brief search of Denver 911 logs shows over a four-year period shows at least 91 documented reports of edible-related calls, incidents ranging from mild hallucinations to violent reactions.

• Brian Nowak:

  But very few, one or two people of negative cases out of how many millions of people use cannabis every single day and have for the last 50 years? I mean, basing things off of very few instances is where I'm having the bigger issue.

• Dr. Kari Franson:

  I think that the best thing that we did was limit what was the maximum dosage that could go into any one edible product.

• Lori Jane Gliha:

  Dr. Kari Franson is an associate professor of clinical pharmacy at the University of Colorado, who helped draft the state's marijuana regulations.

• Dr. Kari Franson:

  With edibles, there is a delay in getting the drug into the system, because it has to be swallowed, it has to be broken up in the gastrointestinal tract, and it has to be absorbed. That can take anywhere from 30 minutes to a few hours.

  And how much gets in can vary depending on what somebody ate that day, if they're on another drug, if they just exercised that day, how much fluid they have in their system. There's a lot of different factors.

• Lori Jane Gliha:

  Meanwhile, the push for marijuana legalization is growing. Oregon and Alaska have the most restrictive edible serving sizes, at 5 milligrams of THC in each. And dozens of others are considering or implementing new marijuana regulations, many looking to Colorado for guidance.

• Dominique Mendiola:

  I would say we have been really diligent in identifying issues and responding to them quickly.

• Lori Jane Gliha:

  Colorado's marijuana coordinator, Dominique Mendiola, says the state is frequently updating its rules to reflect the changing market. In 2018, the state addressed an increasing number of children accessing marijuana by preventing manufacturers from making edibles that look like tempting fruit or animal shapes. And required testing of edibles now checks for consistency and potency.

  It may never be clear exactly how the marijuana edible affected Richard Kirk on the night he murdered his wife, Kris.

• Richard Kirk:

  I think a lot of people are affected by the deep sorrow that people feel about what happened. I hope that they think about Kris, and they think about the people that are making the laws. I would hope that Kris' memory would stay in the forefront.

• Lori Jane Gliha:

  As more states consider legalizing recreational marijuana, the research into the effects of edible marijuana will only become more important.

  For the "PBS NewsHour," I'm Lori Jane Gliha in Denver, Colorado.