Nearly three-quarters of adolescents who use cannabis report using a concentrate, which contains a higher concentration of Δ-9- tetrahydrocannabinol (THC) than dried cannabis, according to a study published in Pediatrics. In addition, the study results suggest that adolescents who use cannabis concentrate, for example, wax or hashish, are at higher risk of developing substance use problems compared with their peers who use nonconcentrate products.
Compared with dried cannabis (ie, marijuana), which has an average THC concentration ranging from 12% to 20%, cannabis concentrates have an average THC concentration ranging from approximately 39% to 69%, noted the authors.
“Understanding the prevalence of cannabis concentrate use in adolescents is important because cannabis use is typically initiated in adolescence, and adolescence is a developmental period characterized by heightened risk for cannabis use disorder and other cannabis-related consequences,” the authors wrote.
To determine the frequency of cannabis concentrate use among adolescents in Arizona, a state in which medical cannabis is legal, the investigators surveyed adolescents in 8th, 10th, and 12th grades. The researchers were examining whether concentrate users had differences in risk factors or substance use problems compared with cannabis users who had not used concentrates.
Of the 47,142 adolescents who were surveyed, 33% reported lifetime cannabis use (either marijuana or concentrate) and 24% reported lifetime concentrate use. Cannabis use increased with age: a total of 19.9%, 35.0%, and 46.4% of 8th, 10th, and 12th graders reported cannabis use, respectively, whereas 14.7%, 25.3%, and 32.9% of 8th, 10th, and 12th graders reported concentrate use in their lifetime. Both cannabis use and concentrate use were more common among girls than boys, as well as in adolescents whose caregivers did not finish high school.
Concentrate users had higher rates of other substance use and were worse off on every risk and protective factor for substance use problems than nonconcentrate users. For example, the odds of e-cigarette use among adolescents who used concentrate was 3.24 times greater than nonconcentrate cannabis users and 24.50 times greater than cannabis nonusers. Adolescents who used concentrate were more likely to have initiated substance use younger than age 17 years.
“Such high rates of concentrate use raise concerns about adolescents’ exposure to high-THC cannabis because some research suggests that use of cannabis with higher THC content is associated with increased risk of cannabis use disorder, cognitive impairment, and psychosis,” the authors noted.
“As findings emerge showing high rates of concentrate use in adolescents, and increased cannabis-related risks associated with use of high-THC cannabis, policy makers might consider putting a limit on THC concentration in cannabis,” concluded the investigators.
Meier MH, Docherty M, Leischow SJ, Grimm KJ, Pardini D. Cannabis concentrate use in adolescents. Pediatrics. 2019;144(3):e20190338.