title: Cannabinoids in oral fluid following passive exposure to marijuana smoke.
abstract: The concentration of tetrahydrocannabinol (THC) and its main metabolite 11-nor-Δ(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) as well as cannabinol (CBN), and cannabidiol (CBD) were measured in oral fluid following realistic exposure to marijuana in a Dutch coffee-shop. Ten healthy subjects, who were not marijuana smokers, volunteered to spend 3h in two different coffee shops in Groningen, The Netherlands. Subjects gave two oral fluid specimens at each time point: before entering the store, after 20 min, 40 min, 1h, 2h, and 3h of exposure. The specimens were collected outside the shop. Volunteers left the shop completely after 3h and also provided specimens approximately 12-22 h after beginning the exposure. The oral fluid specimens were subjected to immunoassay screening; confirmation for THC, cannabinol and cannabidiol using GC/MS; and THC-COOH using two-dimensional GC-GC/MS. THC was detectable in all oral fluid specimens taken 3h after exposure to smoke from recreationally used marijuana. In 50% of the volunteers, the concentration at the 3h time-point exceeded 4 ng/mL of THC, which is the current recommended cut-off concentration for immunoassay screening; the concentration of THC in 70% of the oral fluid specimens exceeded 2 ng/mL, currently proposed as the confirmatory cut-off concentration. THC-COOH was not detected in any specimens from passively exposed individuals. Therefore it is recommended that in order to avoid false positive oral fluid results assigned to marijuana use, by analyzing for only THC, the metabolite THC-COOH should also be monitored.
authors.affiliation: Immunalysis Corporation, Pomona, CA, USA. cmoore@immunalysis.com
authors.forename: Christine
authors.initials: C
authors.lastname: Moore
authors.forename: Cynthia
authors.initials: C
authors.lastname: Coulter
authors.forename: Donald
authors.initials: D
authors.lastname: Uges
authors.forename: James
authors.initials: J
authors.lastname: Tuyay
authors.forename: Susanne
authors.initials: S
authors.lastname: van der Linde
authors.forename: Arthur
authors.initials: A
authors.lastname: van Leeuwen
authors.forename: Margaux
authors.initials: M
authors.lastname: Garnier
authors.forename: Jonathan
authors.initials: J
authors.lastname: Orbita
mesh_terms: D002186:Cannabinoids / Q000032:analysis* / Q000378:metabolism; D015331:Cohort Studies; D013759:Dronabinol / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D005260:Female; D006801:Humans; D007118:Immunoassay; D008297:Male; D008385:Marijuana Smoking / Q000378:metabolism; D009426:Netherlands; D012463:Saliva / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013048:Specimen Handling; D015813:Substance Abuse Detection / Q000379:methods*; D014028:Tobacco Smoke Pollution / Q000032:analysis*; D055815:Young Adult
chemical_list: D002186:Cannabinoids; D014028:Tobacco Smoke Pollution; C016780:11-nor-delta(9)-tetrahydrocannabinol-9-carboxylic acid; D013759:Dronabinol