title: Concentrations of delta9-tetrahydrocannabinol and 11-nor-9-carboxytetrahydrocannabinol in blood and urine after passive exposure to Cannabis smoke in a coffee shop.
abstract: Cannabinoid concentrations in blood and urine after passive exposure to cannabis smoke under real-life conditions were investigated in this study. Eight healthy volunteers were exposed to cannabis smoke for 3 h in a well-attended coffee shop in Maastricht, Netherlands. An initial blood and urine sample was taken from each volunteer before exposure. Blood samples were taken 1.5, 3.5, 6, and 14 h after start of initial exposure, and urine samples were taken after 3.5, 6, 14, 36, 60, and 84 h. The samples were subjected to immunoassay screening for cannabinoids and analyzed using gas chromatography-mass spectrometry (GC-MS) for Delta(9)-tetrahydrocannabinol (THC), 11-nor-hydroxy-Delta(9)-tetrahydrocannabinol (THC-OH), and 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol (THC-COOH). It could be demonstrated that all volunteers absorbed THC. However, the detected concentrations were rather small. None of the urine samples produced immunoassay results above the cutoff concentration of 25 ng/mL. THC-COOH concentrations up to 5.0 and 7.8 ng/mL before and after hydrolysis, respectively, were found in the quantitative GC-MS analysis of urine. THC could be detected in trace amounts close to the detection limit of the used method in the first two blood samples after initial exposure (1.5 and 3.5 h). In the 6 h blood samples, THC was not detectable anymore. THC-COOH could be detected after 1.5 h and was still found in 3 out of 8 blood samples after 14 h in concentrations between 0.5 and 1.0 ng/mL.
authors.affiliation: Institute of Legal Medicine, Johannes Gutenberg-University Mainz, Am Pulverturm 3, 55131 Mainz, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Röhrich
authors.forename: I
authors.initials: I
authors.lastname: Schimmel
authors.forename: S
authors.initials: S
authors.lastname: Zörntlein
authors.forename: J
authors.initials: J
authors.lastname: Becker
authors.forename: S
authors.initials: S
authors.lastname: Drobnik
authors.forename: T
authors.initials: T
authors.lastname: Kaufmann
authors.forename: V
authors.initials: V
authors.lastname: Kuntz
authors.forename: R
authors.initials: R
authors.lastname: Urban
mesh_terms: D000328:Adult; D016902:Air Pollution, Indoor; D002188:Cannabis / Q000737:chemistry*; D013759:Dronabinol / Q000031:analogs & derivatives* / Q000097:blood* / Q000652:urine*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D019570:Inhalation Exposure; D057230:Limit of Detection; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D015203:Reproducibility of Results; D012906:Smoke / Q000032:analysis*; D013997:Time Factors
chemical_list: D012906:Smoke; C001427:11-hydroxy-delta(9)-tetrahydrocannabinol; C016780:11-nor-delta(9)-tetrahydrocannabinol-9-carboxylic acid; D013759:Dronabinol