Lawmakers across the country increasingly are considering legislation that would limit or regulate the potency of marijuana, as states legalize the use of the drug for medical and recreational purposes.
New York will tax recreational marijuana based on its amount of THC, the psychoactive chemical in cannabis, under a law signed last month.
Illinois adopted a potency-related tax when recreational pot sales started last year, and Vermont will limit THC content when its legal market opens as soon as next year.
“There should definitely be limits on THC. Some of these products have as much as 80 to 90 percent THC,” said Amy Ronshausen, executive director of the Drug Free America Foundation. “Most studies that have been done are on low potency marijuana. That being said, in a 2019 advisory, the U.S. Surgeon General said that the risk of physical dependence, addiction and other negative mental health consequences increase with exposure to high concentrations of THC marijuana.”
Other states have discussed setting limits or taxes. Colorado state Rep. Yadira Caraveo this year proposed to ban cannabis products with THC potency at 15%, but the Democrat’s bill was never introduced due to backlash, according to The Denver Post.
Marijuana these days isn’t available only as a rolled-up joint but as concentrates, gummies, sodas, wax and other products that can have higher levels of THC.
In the 1970s, “Woodstock Weed” contained about 1% to 3% THC, but marijuana potency has climbed to an average of 18% to 23%, according to Smart Approaches to Marijuana (SAM). The organization also notes that THC concentrates had an average potency of about 56% in 2017, but many retailers sell products with up to 95%-99% potency.
“We are very supportive of marijuana potency caps and are working to support efforts to install them in several states,” said SAM spokesman Colton Grace, noting efforts in Montana, Colorado and Florida. “There is an overwhelming body of recent research showing that today’s high potency marijuana is linked to potentially severe mental health issues and a heightened risk for addiction. We are also seeing concerning increases in the rate of youth using extremely potent forms of marijuana such as 99% THC vapes and dabs.”
Some states have regulated the amount of THC for at least some products, The Associated Press reported. Vermont limits the chemical in recreational pot to 30% for flower-form marijuana and 60% for concentrates.
Virginia’s new law allows its future Cannabis Control Authority to cap THC levels. In Florida, lawmakers are discussing a proposal to limit THC in medical marijuana.
Last month, the U.S. Senate’s bipartisan Caucus on International Narcotics Control recommended that federal health agencies look into whether pot potency should be capped.
Dr. Peter Grinspoon, a Harvard Medical School professor and board member of Doctors for Cannabis Regulation, argued that if lawmakers tax cannabis too much, it will feed the black market.
“If you make regulated cannabis too expensive, people literally just go and buy it in the illicit market. You know, it’s much less expensive and it’s obviously better for people to buy it in the legal market,” Dr. Grinspoon said. “It’s as safe as cannabis gets. It’s regulated. It doesn’t have lead, heavy metal, fungus — you know exactly what’s in it.”
He said there are legitimate arguments for and against potency caps. Those who argue for limits say some people accidentally take too much, he said
The main problem with high-THC products could be accidental over-ingestion of marijuana-based products, said Dr. Grinspoon, adding that the risk could be reduced with clear labeling and individually wrapped servings.
“No medicine is without side effects. So when people who are pro-cannabis say there are no side effects or harms, that’s ridiculous. And when people exaggerate the harm, that’s ridiculous, too,” he said. “So if you take a bigger dose, there’s going to be more side effects.”
But he added he doesn’t believe “dire warnings” about higher potency marijuana, saying it needs to be studied more.
Morgan Fox, spokesman for the National Cannabis Industry Association, also noted that alcoholic beverages with more than 90% alcohol content are legal in most states, despite the “significantly more dangerous nature of those products compared to even the most concentrated THC products.” He noted out dronabinol, an FDA-approved prescription cannabinoid that is nearly 100% THC, is legal.
χ This article is based in part on wire service reports.