Abstract
Samples taken from seizures of imported illicit heroin preparations of known geographical origin have been examined. The typology developed in a previous survey of illicit heroin products is applicable to virtually all the samples studied in this work. On the basis of these observations it is possible to give an opinion as to the origin of some samples of illicit heroin of unknown provenance. The observation in the previous survey that unrelated samples of illicit heroin possess unique chemical profiles has been confirmed by the present results.