Evaluation of the on-site Draeger DrugTest 5000 in occasional and chronic frequent smokers following controlled cannabis smoking

Background Cannabis is the most commonly reported illicit drug in drugged driving cases. Achieving accurate oral fluid (OF) cannabinoid on-site results is challenging and essential. Aims Device performance and OF cannabinoid detection windows 30h post-smoking were evaluated in occasional (<2x/week) and frequent (≥4x/week) cannabis smokers. Methods 10 occasional and 14 frequent smokers (18-45 years) provided written informed consent for this Institutional Review Board-approved study, and smoked ad libitum one 6.8% THC cannabis cigarette. OF was collected with the DrugTest 5000 test cassette and Oral-Eze® collector (Quest Diagnostics) before and frequently up to 30h post-dose. Test cassettes were analyzed immediately and compared to two-dimensional gas chromatography mass spectrometry (2D-GCMS) cannabinoid results from simultaneously collected Oral-Eze OF. Results 404 paired OF were collected; 9 samples (2.2%) were invalid, yielding 395 OF pairs for comparison. Sensitivity, specificity and efficiency were 75.3, 94.1, and 81.8% and 66.4, 98.9, and 73.9% with 2 ng/mL THC proposed SAMHSA and 1 ng/mL DRUID confirmation cutoffs, respectively. Sensitivity was 6-11% higher in chronic frequent as compared to occasional cannabis smokers due to longer detection windows and higher true positive rates. Median (range) last detection times with the DrugTest 5000 were 12h (4-24) and 21h (1->30) for occasional and frequent smokers, respectively (p=0.12, >30 assigned as 30h). Three frequent smokers were still positive at 30h, but had up to 5 negative specimens prior to 30h. Discussion and conclusions Sensitivity of the DrugTest 5000 5 ng/mL cutoff was lower for occasional as compared to chronic frequent smokers over the extended 30h monitoring window with the 2 and 1 ng/mL confirmation cutoffs; however, these authentic data after controlled smoking document the best performance to date for on-site cannabinoid tests. Sensitivity within 6 and 8h time frames, representing recent smoking, were 85.6 and 84.7%; and 84.0 and 82.5% at the proposed SAMHSA and DRUID confirmation cutoffs, respectively. Supported by the Intramural Research Program, NIH, National Institute on Drug Abuse Introduction Cannabis sativa (marijuana) has been smoked for its medicinal and psychoactive properties for thousands of years and is the most widely consumed illicit drug in the world (Vega et al.,