Particle size analysis of six illicit heroin preparations seized in the UK

Illicit heroin is rarely pure and may contain a number of other substances. The total particle size distribution in six illicit heroin preparations was analysed using a Malvern 2600 Particle Analyser and by sieving. The pattern of heroin distribution amongst these particles was determined by HPLC. The results show that a representative illicit heroin particle is approximately 45 mu m in diameter (137 mu mol heroin) and that particles occur over a wide size range? from at least 5.8 to 564 mu m in diameter. Aggregated data for the samples studied showed that the overall distribution of heroin particle size largely follows the total particle size distribution, but that this correlation is not necessarily true for individual drug preparations. These results have important implications for any system designed to detect concealed illicit heroin preparations by collection and analysis of drug particles.