WA House COG - Work Session
(September 15, 2020) - UW ADAI

Committee members learned about cannabis-related research from academics affiliated with the University of Washington Alcohol and Drug Abuse Institute (UW ADAI) and heard their concerns about concentrated cannabinoid products.

  • Beatriz Carlini, a UW School of Public Health Affiliate Associate Professor, presented information on "High Potency Cannabis" and research on “how they are measured and researched, who are the consumers, health risks and consequences, and a little bit about policies” (audio - 13m, video).
    • Carlini began by saying “high potency” cannabis had been defined as having a tetrahydrocannabinol (THC) concentration “of more than 10%, and that was right before the market forces of legalization redefined that concept.” She accepted that potency-focused cultivation and concentrates were “not invented by legalization, by no means, but was legalization...that brought a possibility of mass production of this manufactured products, cannabis extracts.”
      • Carlini presented data showing low potency cannabis flower had disappeared from retail stores.
      • Carlini contrasted concentrates, which had cannabinoid concentrations “mostly in 60 to 90%” range, which she felt was “entirely a different animal” than the cannabis plant. Carlini testified that extraction of cannabis was “mostly using butane...adding terpenes from other vegetables and other plants, refine and process a little like” commercial food manufacturing but with less research. She believed this process of cannabis product innovation led to new paraphernalia like “dabs and all the different ways of vaping cannabis.”
      • Carlini noted that Washington's extract market share grew from 9% in 2014 to 24% by 2017, and that it was currently “35% of the market” in Washington, representing a “nearly ten-fold increase in sales.” 
        • Some of this growth can be attributed to other factors. As a writer covering the launch of retail sales in Washington for the Marijuana News Network (MJNN), I observed the stores opening across the state throughout 2014 had limited types of products given the small number of licensed processors in operation. At the first retailer to open in Vancouver, I wrote that “the supply issue will be resolved soon enough...we will soon be offering the finest quality weed at a reasonable price, as well as edibles and more.”
        • UW ADAI’s data also couldn’t account for extract sales in gray market dispensaries prior to their prohibition by law in 2015, and closure the following year. I noted one nearby dispensary when writing about Thurston County’s first legal retailer.
    • Increasingly concerned about health impacts of concentrated cannabinoids, UW and WSU staff joined state and community prevention organizations to form a “Cannabis Concentration Workgroup” within the Washington State Prevention Research Subcommittee (WA PRS) in March.
      • The formation of the work group may have been a response to the failure to advance HB 2546, which proposed a cap on THC concentrations in cannabis products. However, Carlini expressed concerns in 2019 as a member of WSLCB’s potency tax work group. She was joined in that work group by WSU Human Development Professor Laura Hill, who was a co-chair of WA PRS at the time, and UW Endowed Professor of Prevention Kevin Haggerty, who was appointed co-chair of WA PRS in January.
      • The WA PRS cannabis work group’s goal was development of a “consensus statement on health risks of high concentration cannabis” which Carlini said would be available to policymakers and the public before November 2020. She said the group “departed” from an approach which would “check if the science really backs what we have been perceiving as work in the community.” Instead, the group planned to assert “that high potency cannabis is more detrimental to health than lower potency, so there is a dose-response relationship.”
      • Carlini said the work group members believed “high potency cannabis use is an issue of equity, disproportionately affects marginalized or vulnerable populations,” another subject discussed in the cannabis potency tax work group.
    • Carlini called attention to research at UW by Caislin Firth, who used data from the Behavioral Risk Factor Surveillance System (BRFSS) to look for common traits among adults who vaped or used higher concentrated cannabis dabs. Firth asserted vape users tended to be male, with higher incomes and college education. Dab users were also likely male, but skewed towards being younger, Latinx, and with less income and health insurance.
    • Although cannabis use among underage populations “has not increased when we look at the general prevalence,” Carlini said that some youth were vaping or dabbing at increasing rates according to the state’s Healthy Youth Survey (HYS).
      • WSLCB Public Health Education Liaison Sara Cooley-Broschart briefed on the HYS’s impact on agency activity in December 2019 and on January 8th
    • Carlini credited the work of Julia Dilley, the Principal Investigator at Program Design and Evaluation Services, a joint office of the Multnomah County Health Department and the Oregon Department of Human Services Division of Public Health, and a Senior Research Scientist/Epidemiologist at UW.
      • Carlini said Dilley and other researchers studied poison center data nationwide from 2015 to 2017, “and they clearly see that the plant material” reports were “stable” but that there were “increasing calls to the poison centers asking for help is concentrated on vape concentrate products and also edibles.” She reported that the majority of poison center calls for cannabis plants involved “co-using” with another substance, but that 82% of calls for concentrates, edibles, and vape products were “calling because they are experiencing negative consequences related to this manufactured product.”
      • Dilley briefed the WSLCB Board in September 2018, was a participant on the WSLCB potency tax work group, and briefed the agency’s HYS work group in October 2019
      • More recently, Dilley was listed as a reference for Center for Toxicology and Environmental Health (CTEH) health scientist Katelyn Hall in the unsuccessful proposal from TerraGraphics, Inc. to consult for the Washington State Task Force on Marijuana Odor. TerraGraphics, perhaps better equipped to help monitor radioactive solid waste burial grounds at the Hanford site, partnered with “CTEH as our subcontractor to provide human health and toxicological expertise for this scope.”
    • Carlini presented other researchers’ “most relevant” reviews of academic studies between 2018 and 2020. At UW, Denise Walker and Jason Kilmer found that “the higher the potency, higher is the chance of developing addiction to cannabis” and “THC concentration increases the chance of cannabis use disorder, particularly among young people.”
    • Echoing a point made earlier by her WSU colleagues on limits to constructing human studies involving the administration of cannabis products, Carlini said there wouldn’t be studies based on “randomizing people to see if they’re going to get addicted later. This is not possible. We’re never going to get that.” Carlini asserted that “the studies are well done, and well controlled, and have sophisticated designs, but they observe people over time. They do depend on what people tell us because that’s the nature of doing research in this area.”
    • Carlini then mentioned psychosis, and McDonell’s literature review which claimed that “the use of higher potency cannabis increased nearly five times the odds of developing psychotic disorders.” Carlini said that “no one is trying to disseminate panic or anything, but [a dose-response relationship] is what the data says.”
    • Carlini concluded by saying “we live in a legalization era where the market runs the show. There are many ways you can legalize cannabis.” She argued that Washington’s market was driven by “product diversification and innovation. That’s how it is for cell phones, for cars” where consumers were encouraged “to want to consume more.” Meanwhile, science and regulation “walks behind” that curve. Carlini dropped an open question: “who owns the burden to prove safety and quality of the products sold?”

Information Set