Citing concerns about a suspected connection between cannabis and psychosis, a group of Washington state lawmakers wants to slash the allowed potency of all non-medical cannabis concentrates, limiting THC levels to no more than 10%.

The new proposal, House Bill 2546, would dramatically alter the face of Washington’s legal cannabis landscape by outlawing the vast majority of state-licensed vape cartridges, dabbable extracts, and other concentrated products. Such products are increasingly popular with consumers, lawmakers noted in the bill, accounting for nearly 40% of the state’s legal cannabis sales in 2019.

Experts warn that the move, ostensibly aimed at improving public health, could quickly backfire. Leo Beletsky, a professor of law and public health at Northwestern University, said that a blanket ban on such a large swath of popular products would likely drive consumers into the illegal market.

“There may well be rationale for eliminating some portion of the riskiest products on the market if there’s evidence to support that, but doing that with 40% off the products would make very little sense,” Beletsky said. “If 40% of the market is toward these products and then you ban them, you’d definitely be creating a push towards the black market.”

Illegal concentrates led to 57 deaths

And that’s where far more serious health dangers may lurk. Federal Centers for Disease Control (CDC) officials have concluded that vitamin E oil used to dilute illegal-market vape cartridges has been responsible for nearly all cases of VAPI (also known as EVALI), the deadly lung condition that has killed at least 57 Americans in the past year. Vitamin E oil did not show up in the state-licensed market because potency testing, which is required in legal markets, would reveal cartridges cut with vitamin E oil to be severely lacking in THC—and thus all but unsellable.

Beletsky called the proposed 10% THC cutoff “puzzling” and “arbitrarily low.” Recent studies have indicated a link between cannabis use and psychosis in a very small percentage of consumers, he acknowledged, but the science is far from settled. Some evidence, for example, suggests that patients with psychosis may actually be self-medicating with THC to better cope with symptoms.

“I think there is a reason for concern,” Beletsky said, “but we need far more information and far more high-quality research to try to guide these legal steps.”

10% pulled out of the air

The bill’s 10% cutoff comes from a study that defined “high-potency” cannabis as products containing more than 10% THC. The study found that regular consumers of high-THC products had higher instances of psychosis. But as Beletsky pointed out, the 10% threshold appears to be arbitrary, borrowed by lawmakers not because of its scientific grounding but simply because it was there.

“They cite this study where they used a 10% number for a cutoff for what they define to be high-potency,” he said. “I’m not sure that is a number that makes sense.”

Low potency would require more diluents

The new bill also raises other questions, such as how to effectively produce such low-potency extracts. Because concentrates are usually made from cannabis flower or trim that itself contains about 10% to 30% THC, concentrated extracts almost by definition contain more. Typical concentrates contain about 40% to 70% THC, while some purified products can approach nearly 100% THC.

To create concentrate products that would comply with HB 2546’s strict limit, processors would likely have to dilute their products or start with especially low-potency plant material, industry experts said.

Daniel Luebke, director of marketing and brand for Seattle-based cannabis extractor Heylo, said that to comply with the new rule, concentrate producers would need to blend THC extracts either with other cannabinoids, such as CBD, or add cutting agents to dilute the concentration.

“We’re trying to preserve the chemistry that’s in the flower and just make a concentration of it,” Luebke said. “To cater to the [new 10% THC] legal demand, we would have to be making an inferior product, essentially, and going away from the method we’ve developed, that our customers love.”

‘No measurable benefit’

Passage of HB 2546 wouldn’t ultimately impact consumer demand for high-potency concentrates, Luebke predicted. “It’s a question of whether they’re getting safe products and whether the state’s getting that revenue.”

Concentrate products manufactured by state-licensed companies are required to undergo lab testing, and may be recalled at the first sign of trouble. New state rules established after the nationwide vaping scare now limit many dangerous additives to vape cartridges and other state-licensed products. There are no such controls over illicit-market products.

Christine Bryant, marketing director for cannabis retailer Hashtag, said passage of HB 2546 “would decimate our inventory.” Even most of the store’s high-CBD concentrates, she said, come in at about 20% THC.

“I think I can even wrap my mind around the spirit of the bill,” Bryant said, acknowledging that the consequences of psychosis are “terrifying.” But she remains unconvinced “that a 10% cap on THC concentrates would provide any measurable benefit to end consumers.”

‘You will not feel intoxicated’

Washington’s cannabis laws clearly contemplate adult-use consumers who want to get high, Bryant said. Under the HB 2546, she argued, it’s not clear they’d be able to.

“If you come into the store saying, ‘I want to get high, please give me a concentrate with 10% THC or less,’” she said, “the response is likely going to be, ‘You will not feel intoxicated.’”

Reviving the BHO fire problem

Consumers seeking higher-potency extracts would be pushed to the unlicensed market, she predicted—or, worse, would try to make extracts at home. Home extraction can cause explosions if the volatile chemicals typically used catch fire.

'Why have a legal market if you're going to encourage home lab production of concentrate?'

Christine Bryant , cannabis retailer Hashtag

In the era prior to the opening of Washington state’s adult-use cannabis stores, home extraction fires had become a public safety issue. An Oct. 2013 fire that started in a BHO operation in a Bellevue, WA, apartment, claimed the life of the city’s former mayor, who happened to live in a nearby unit.

“Producing concentrate outside of a licensed producer-processor lab is so incredibly dangerous,” Bryant said. “Why have a recreational legal cannabis market in Washington state if one of the outcomes would be to encourage home lab production of concentrate?”

It’s not yet clear what kind of reception the measure will get in Olympia, but cannabis businesses and trade associations are watching it closely. Luebke, at Heylo, says HB 2546 is one of a handful this legislative session that have put him on edge—and the session only started on Monday.

Crazy week in the legislature

“It’s been a crazy week,” he said. “This is the most significant time that we’ve been concerned that there’s change happening in Olympia that could tremendously adversely affect our future.”

HB 2546’s sponsors include state Reps. Lauren Davis (D-32), Chris Corry (R-14), Brad Klippert (R-8), Jeremie Dufault (R-15), Christine Kilduff (D-28), Paul Harris (R-17), Lisa Callan (D-5), Mari Leavitt (D-28), My-Linh Thai (D-41), Tana Senn (D-41), Sherry Appleton (D-23), Tina Orwall (D-33), Sharon Wylie (D-49), Laurie Dolan (D-22), Luanne Van Werven (R-42), Amy Walen (D-48), Kelly Chambers (R-25), Jenny Graham (R-6), Bill Ramos (D-5), Shelley Kloba (D-1), Gerry Pollet (D-46), and Debra Lekanoff (D-40).

Reps. Davis, Corry, and Klippert did not immediately respond to requests for comment on their bill.