Cannabinoids and metabolites in expectorated oral fluid following controlled smoked cannabis

摘要

Background: Δ 9-Tetrahydrocannabinol (THC) in oral fluid (OF) implies cannabis intake, but eliminating passive exposure and improving interpretation of test results requires additional research. Methods: Ten adult cannabis users smoked ad libitum one 6.8% THC cigarette. Expectorated OF was collected for up to 22. h, and analyzed within 24. h of collection. THC, 11-nor-9-carboxy-THC (THCCOOH), cannabidiol, and cannabinol were quantified by 2-dimensional-GCMS. Results: Eighty specimens were analyzed; 6 could not be collected due to dry mouth. THC was quantifiable in 95.2%, cannabidiol in 69.3%, cannabinol in 62.3%, and THCCOOH in 94.7% of specimens. Highest THC, cannabidiol, and cannabinol concentrations were 22370, 1000, and 1964 μg/l, respectively, 0.25. h after the start of smoking; THCCOOH peaked within 2. h (up to 560. ng/l). Concentrations 6. h after smoking were THC (0.9-90.4 μg/l) and THCCOOH (17.0-151. ng/l) (8 of 9 positive for both); only 4 were positive for cannabidiol (0.5-2.4 μg/l) and cannabinol (1.0-3.0 μg/l). By 22. h, there were 4 THC (0.4-10.3 μg/l), 5 THCCOOH (6.0-24.0. ng/l), 1 cannabidiol (0.3 μg/l), and no cannabinol positive specimens. Conclusions: THCCOOH in OF suggests no passive contamination, and CBD and CBN suggest recent cannabis smoking. Seventeen alternative cutoffs were evaluated to meet the needs of different drug testing programs.