Variation in the THC content in illicitly imported Cannabis products--Part II.

The tetrahydrocannabinol (THC) contents of 220 samples of fresh illicit Cannabis products seized on entry into the United Kingdom of Great Britain and Northern Ireland over the period 1979-1981 have been determined by gas chromatography. During that period there was a general increase in the quality of both cannabis and cannabis resin, but with wide variations in THC contents both within and between countries. Some very high quality samples of cannabis, cannabis resin and cannabis oil from the Indian sub-continent have been analysed. There have been considerable changes in the number of fresh samples from several countries, compared with the previous survey. Fresh cannabis oil samples were very rare during the period covered by this survey.