Detection of cannabinoids in homicide victims and motor vehicle fatalities

A gas chromatographic/mass spectrometric (GC/MS) procedure is described for the detection and measurement of delta 9-tetrahydrocannabinol, 11-hydroxy-delta 9-tetrahydrocannabinol, and 11-nor-delta 9-tetrahydrocannabinol-9-carboxylic acid in blood, or 11-nor-delta 9-tetrahydrocannabinol-9-carboxylic acid in urine. About 50% of all homicide victims and motor vehicle drivers killed in Bexar County in 1985 were tested for the presence of cannabinoids. Of 130 homicides and 69 drivers tested, blood was analyzed primarily in all but 15 and 3 cases, respectively. In these latter cases, blood analyzed after urine was found to be positive. Of the homicide victims, 44 (34%), and of all drivers, 19 (28%), tested were positive for one or more of the cannabinoids. As a separate group, 16 motorcycle drivers tested had 38% positive as compared with 25% of the other vehicle drivers. Ethyl alcohol was present in 55% of the drivers, and in 63% of the homicide victims. Drugs other than alcohol or cannabinoids were found in 10% of the drivers, and in 12% of the homicide victims.