title: Measurement of delta 9-tetrahydrocannabinol (THC) in whole blood samples from impaired motorists.
abstract: The major psychoactive cannabinoid in marihuana, delta 9-tetrahydrocannabinol (THC) was measured in 1792 randomly selected blood specimens from erratic motorists arrested for impairment who submitted to blood alcohol sampling. Of these specimens, 14.4% were positive for THC (greater than or equal to 5.5 ng/mL). In those erratic driver specimens negative for alcohol THC positives rose to 23%. Drivers who used marihuana covered a broad age range. Aliquots of hemolyzed blood (10 microL) were analyzed by a sensitive radioimmunoassay (RIA) not requiring extraction. RIA accuracy and specificity were validated by gas liquid chromatography/mass spectroscopy (GLC/MS) split pair analysis (correlation coefficient = 0.93). This initial experience should facilitate and amplify a program designed to set forth the epidemiology of marihuana use in motorists and possible behavioral correlates.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001334:Automobile Driving; D013759:Dronabinol / Q000097:blood*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D002189:Marijuana Abuse / Q000175:diagnosis*; D008875:Middle Aged; D011863:Radioimmunoassay
chemical_list: D013759:Dronabinol