Detection of Δ9 -tetrahydrocannabinol (THC) in oral fluid using two point-of-collection testing devices following oral administration of a THC and cannabidiol containing oil

Anastasia Suraev; Danielle McCartney; Richard Kevin; Rebecca Gordon; Ronald R Grunstein; Camilla M Hoyos; Iain S McGregor

doi:10.1002/dta.3658

Detection of Δ⁹ -tetrahydrocannabinol (THC) in oral fluid using two point-of-collection testing devices following oral administration of a THC and cannabidiol containing oil

Drug Test Anal. 2024 Feb 27. doi: 10.1002/dta.3658. Online ahead of print.

Authors

Anastasia Suraev^{1

2

3

4}, Danielle McCartney^{1

3

4}, Richard Kevin^{1

5

6}, Rebecca Gordon¹, Ronald R Grunstein^{2

7

8}, Camilla M Hoyos^{2

9}, Iain S McGregor^{1

3

4}

Affiliations

¹ Lambert Initiative for Cannabinoid Therapeutics, University of Sydney, Sydney, New South Wales, Australia.
² Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, Sydney, New South Wales, Australia.
³ School of Psychology, Faculty of Science, University of Sydney, Sydney, New South Wales, Australia.
⁴ Brain and Mind Centre, University of Sydney, Sydney, New South Wales, Australia.
⁵ St Vincent's Hospital Sydney, Sydney, New South Wales, Australia.
⁶ School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.
⁷ Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.
⁸ Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.
⁹ Faculty of Medicine and Human Health Sciences, Macquarie University, Sydney, New South Wales, Australia.

PMID: 38414100
DOI: 10.1002/dta.3658

Abstract

Point-of-collection testing (POCT) devices are widely used in roadside and workplace drug testing to identify recent cannabis use by measuring the presence of Δ⁹ -tetrahydrocannabinol (THC) in oral fluid (OF). However, the performance of POCT devices with oral medicinal cannabis products remains poorly described. In a randomised, double-blinded, crossover trial, adults with insomnia disorder (n = 20) received a single (2 mL) oral dose of oil containing 10 mg THC + 200 mg cannabidiol, or placebo, prior to sleep. Participants were tested with the Securetec DrugWipe® 5S (10 ng/mL THC cut-off) and Dräger DrugTest® 5000 (25 ng/mL THC cut-off) POCT devices at baseline (pre-treatment) and then at 0.5, 10, and 18 h post-treatment. An OF sample, taken at each time point, was also analysed using liquid chromatography-tandem mass spectrometry. Large individual variability in OF THC concentrations was observed 0.5 h post-treatment (range: 0-425 ng/mL; mean (SD) 48.7 (107.5) ng/mL). Both the Securetec DrugWipe® 5S and DrugTest® 5000 demonstrated poor sensitivity to THC at 0.5 h post-treatment (25% and 50%, respectively). At 10 and 18 h post-treatment, all participant OF THC concentrations were below screening cut-offs, and all test results were negative. These findings highlight the relatively poor sensitivity of both devices in detecting recent use of an oral medicinal cannabis product. They also suggest a low probability of obtaining a positive THC result the morning after ('one-off') use. Further research is required to establish the probability of obtaining a positive THC result with regular medicinal cannabis use.

Keywords: THC; cannabis; drug testing; oral fluid; point-of-collection testing.

Grants and funding

Lambert Initiative for Cannabinoid Therapeutics