Impurity profiling/comparative analyses of samples of 1-phenyl-2-propanone.

1-Phenyl-2-propanone (P-2-P), also known as benzyl methyl ketone (BMK), is the main precursor used in amphetamine synthesis. In recent years, the number of seizures of P-2-P from both licit and illicit drug manufacture has increased. The present article comprises a discussion of some of the largest seizures of P-2-P diverted from regular production to the illicit market. It also presents the methods used in clandestine laboratories to synthesize P-2-P and a forensic approach to identify and differentiate between these methods. To that end, and to facilitate the monitoring of the P-2-P market, a method of P-2-P impurity profiling was designed for comparative purposes and for the identification of the synthesis route. P-2-P samples were analysed by means of gas chromatography/mass spectrometry (GC/MS). Out of 36 identified impurities, 14 were selected as markers for sample comparison. On the basis of the GC peak areas of those 14 markers, a cluster analysis was carried out, resulting in three clusters, each corresponding to a given P-2-P synthesis route. The results of P-2-P impurity profiling are stored in both a forensic database and a police database. The forensic database comprises chemical data, such as those on P-2-P purity, additives and specific impurities, as well as information on seized P-2-P samples having a similar impurity profile. Data stored in the police database, which is linked with the forensic database by case identification number, cover the circumstances of seizures and personal details of offenders. The databases enable the full use of forensic data in intelligence work and police investigative activities.