A RESEARCH NOTE - THE OUTCOME OF GC MS/MS CONFIRMATION OF HAIR ASSAYSON 93 CANNABINOID (+) CASES/

This article reports the outcome of gas chromatography/tandem mass spe ctrometry confirmations for THC and carboxy-THC on 93 hair samples scr eened by RIA for cannabinoids. The samples were taken from probationer s in Pinellas County, FL, who voluntarily provided the research staff with six hair and six urine specimens, collected at 1-month intervals. There were 40 samples that were RIA (+), urinalysis (-). Samples were selected which had cannabinoid (+) outcomes for hair, urine, or both. The THC and/or the carboxy-THC was (+) on confirmation. Of these 40 s amples, 22 were (+) for both THC and carboxy-THC, 15 were (+) for THC but not carboxy-THC, and three were carboxy THC (+), but THC (-). Only one sample had a (+) RIA, but was (-) for both THC and carboxy-THC on confirmation. RIA detection of cannabinoids was confirmed in nearly a ll cases. Most cases that were RIA (-) but urine (+) were cannabinoid (+) when analyzed by GC/MS/MS.