The illegal production of synthetic drugs in clandestine laboratories is an emerging threat within the European Union, necessitating improved methods for law enforcement agencies to locate these illegal sites. Combining gas chromatography and ion mobility spectrometry is a promising technology for reliably detecting trace amounts of substances in the gas phase. Therefore, the feasibility of detecting precursors involved in methamphetamine synthesis was investigated in this work. It is shown that relevant precursors of the three main synthesis pathways of the most prominent precursor, benzyl methyl ketone, naming the Dakin-West method, the nitrostyrene method and the Baeyer-Villinger pathway can be detected at concentrations down to single-digit ppbv levels. Reliable detection of these substances is based on retention time and reduced ion mobility, minimizing cross-sensitivities. Finally, using a real seized sample of benzyl methyl ketone, it was demonstrated that by-products from the synthesis can be detected in the headspace of such a sample, potentially allowing for drug profiling by sampling the gas phase near suspicious premises. [Author's abstract]

Highlights:
Detection of relevant chemicals of methamphetamine synthesis by GC-IMS.
Limits of detection down to single-digit ppbv range.
Detection based on retention time and reduced ion mobility minimizes cross-sensitivities.
Identification of the synthesis pathways of a seized sample of BMK.