Activation analysis of rare-earth elements in opium and cannabis samples

Rare earth concentrations in 65 Opium, Cannabis and Cannabis resin samples seized from various parts of world were determined by destructive NAA. Great variations in absolute element concentrations, but only small significant differences of rare earth concentration ratios were found, indicating inconsiderable biogeochemical fractionation. The mean values of these ratios correspond with the relative abundances of the rare earths in the upper continental earth's crust.