Delta-9-tetrahydrocannabinol Levels in Street Samples of Marijuana and Hashish: Correlation to User Reactions

Abstract

In a 6 yr period, 435 alleged cannabis samples were accessioned by an urban street drug analysis program, and clinical histories were correlated with laboratory results. The most common reason for submission of a sample was suspicion of adulteration; however, such samples were usually unadulterated but had high potency as measured by .DELTA.9-tetrahydrocannabinol concentration. Adverse reactions occurring in nonadulterated samples were not associated with high potencies. The validity of cannabis products distributed illicitly and analyzed was over 94%. Exotic varieties were more potent than less expensive cannabis. The absolute amount of .DELTA.9-tetrahydrocannabinol ranged from 1.5-144.9 mg.