Quantitative GC-MS analysis of D(9)-tetrahydrocannabinol in fiber hemp varieties.

A sensitive and specific method for the determination of total available D(9)-tetrahydrocannabinol in fiber hemp varieties is described. The method was used for the regulatory purposes in which the detection of higher than the maximum allowed concentration of the psychoactive cannabinoid, D(9)-tetrahydrocannabinol, in industrial fiber hemp would result in cancellation of the grower's license. Cannabinoids were extracted from dry leaf powder into hexane containing internal standard chrysene-d(12) using sonication. D(9)-Tetrahydrocannabinol in the extract was separated by gas chromatography and quantitated by mass spectroscopy. A linear calibration range extending to 40 ppm and a limit of detection of 0.2 ng were obtained by using the total ion current mode of detection.