Marihuana metabolites in urine of man. VII. Excretion patterns of acidic metabolites detected by sequential thin layer chromatography.

The 11-oic acid metabolites of delta-9-tetrahydrocannabinol (THC), cannabinol (CBN), and cannabidiol (CBD) can be identified presumptively in human urine using standard thin layer chromatographic procedures. Other acidic metabolites are also excreted but these are not yet identified. These acidic metabolites appear in urine soon after exposure but persist for at least 48 to 72 hours. Such long persistence does not permit their detection to be used for forensic purposes. Using only simple chemical methods, we have been able to identify presumptively the 11-oic acids of THC, CBN and CBD in the urine of persons taking these materials. A sequential thin-layer chromatography system we have devised provided the basis for this first report of such isolation without the use of labeled drug or mass spectrometric methods.