There are five chapters presented in this thesis. The first chapter deals with the development and validation of an analytical method, incorporating HPLC, for the analysis of MDMA in illicitly produced ecstasy tablets. In all 100 tablets were analysed and the MDMA content on average was found to be 79.01mg.

The second chapter involved the analysis of route specific compounds (two pyrimidines and N-formyl BDB) generated by the synthesis of MBDB that had been synthesised via the Leuckart route. HPLC and GC-MS methods were developed and validated of for the analysis of the three target compounds. Solid phase extraction and liquid-liquid extraction were assessed as potentially suitable methods for the extraction of the three target compounds from MBDB synthesised via the Leuckart route. Street samples of MBDB were analysed and it was discovered that three of the tablets were likely to have been synthesised via Leuckart route.

The most likely routes of synthesis of MDA, MDMA, MDEA, MBDB and 4-MTA were investigated in the Department of Pharmaceutical Chemistry. The third chapter involved subjecting impurities, intermediates and products generated by the routes investigated, to GC-MS analysis. Mass spectral data recorded was incorporated into a software based library which could be used as a forensic tool for the attempted identification of routes of synthesis. Samples licitly prepared Ecstasy and samples of illicitly prepared Ecstasy were subjected to GC-MS analysis. Where possible, routes of synthesis were identified with the aid of the library.

Chapter IV involved the analysis of the 100 urine samples, taken from clients of the methadone programme in the Drug Treatment Centre in Dublin, which had tested positive for amphetamines on EMIT screening. A GC-MS method was used to determine whether the type of amphetamines being abused were non-ring substituted (amphetamine, methamphetamine), ring-substituted propanamines (MDA, MDMA, 4-MTA) or ring-substituted butanamines (MBDB, BDB). Amphetamine and methylenedioxy propanamines were found however, there was no abuse of 4-MTA or ring-substituted butanamines noted.

The final chapter used GC-FID to determine the cannabinoid content of products of the plant Cannabis sativa seized and./or grown in the Republic of Ireland. THC, CBD and CBN levels were determined for 62 samples of cannabis resin, 5 samples of herbal cannabis and 21 samples hemp. The average levels of THC, CBD and CBN in resin were 2.11%, 2.19% and 2.13% respectively. The average levels of THC, CBD and CBN in hemp were 0.06%, 1.61% and 0.06% respectively. The average levels of THC, CBD and CBN in herb were 0.20%, 0.13% and 0.65% respectively.