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Background: Traditional biomarkers for heavy alcohol use include serum carbohydrate-deficient transferrin (CDT), the enzymes aspartate aminotranserase (AST), and alanine aminotransferase (ALT) as well as gamma-glutamyl transferase (GGT). Measurement of the nonoxidative ethanol metabolite, ethyl glucuronide (EtG) in hair, has been proposed as a new marker with superior qualities. The aim of this study was to investigate the sensitivity of EtG in hair to detect heavy alcohol use compared with CDT, AST, ALT, and GGT. We also wanted to study the quantitative relation between alcohol intake and the different biomarkers. Methods: Sixteen patients with a history of heavy alcohol use over the previous 3 months were recruited directly after admission to a withdrawal clinic. They were thoroughly interviewed about their drinking pattern as well as relevant diseases and use of medicines or drugs. Serum was sampled and analyzed for %CDT, AST, ALT, and GGT. Hair samples were collected and analyzed for EtG. Results: The mean estimated daily intake (EDI) over the previous 3 months was 206 ± 136 g pure alcohol. All patients fulfilled the criteria for heavy alcohol use. The sensitivity to detect heavy alcohol use was 64% for %CDT, 67% for AST, 67% for ALT, 93% for GGT, and 94% for EtG. There was no correlation between the quantitative values of EDI and %CDT, AST, ALT, and GGT. There was a positive, statistically significant correlation between EDI and the level of EtG in hair. Conclusions: In this study, EtG in hair and GGT showed the best sensitivity to detect heavy alcohol use and there was a positive correlation between EDI and the concentrations of EtG in hair. Before giving recommendations for clinical practice, further studies should be carried out on larger materials and populations with a wider range of alcohol intake.

Pyrrolidinophenones represent one emerging class of newly encountered drugs of abuse, also known as 'new psychoactive substances', with stimulating psychoactive effects. In this work, we report on the detection of the new designer drug α-pyrrolidinohexiophenone (α-PHP) and its phase I and II metabolites in a human urine sample of a drug abuser. Determination and structural elucidation of these metabolites have been achieved by liquid chromatography electrospray ionisation quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). By tentative identification, the exact and approximate structures of 19 phase I metabolites and nine phase II glucuronides were elucidated. Major metabolic pathways revealed the reduction of the ß-keto moieties to their corresponding alcohols, didesalkylation of the pyrrolidine ring, hydroxylation and oxidation of the aliphatic side chain leading to n-hydroxy, aldehyde and carboxylate metabolites, and oxidation of the pyrrolidine ring to its lactam followed by ring cleavage and additional hydroxylation, reduction and oxidation steps and combinations thereof. The most abundant phase II metabolites were glucuronidated ß-keto-reduced alcohols. Besides the great number of metabolites detected in this sample, α-PHP is still one of the most abundant ions together with its ß-keto-reduced alcoholic dihydro metabolite. Monitoring of these metabolites in clinical and forensic toxicology may unambiguously prove the abuse of the new designer drug α-PHP.

A method for the rapid and robust confirmation of 11-nor-∆9-tetrahydrocannabinol-9-carboxylic acid (THCA) in urine involving basic hydrolysis with NaOH and direct injection of the hydrolysate in a column-switching LC-MS-MS system was developed and validated. THCA-d3 was used as internal standard. Detection was performed in negative-ion mode by monitoring the transitions from the [M-CO(2) ]- ion m/z 299.2→245.2 and and m/z 299.2→191.1 that were found to provide a better signal-to-noise ratio than the transition from the pseudomolecular ion at m/z 343. The high sensitivity of detection enabled the injection of a small volume (10 µl) of the NaOH hydrolysate which, together with the applied column switching system, proved to confer ruggedness to the method and to avoid the deterioration of the instrumental apparatus despite the large amount of inorganic ions in the hydrolysate. The LLOQ was established at 5 ng/ml, and the LLOD was calculated as 0.2 ng/ml (S/N =3). The method was submitted to thorough validation including evaluation of the calibration range (5-500 ng/ml), accuracy and precision, matrix effects, overall process efficiency, autosampler stability, carryover and cross-talk, and 10-times reduction of sample volume (0.1 ml). Proof of applicability was obtained by direct comparison with the reference GC-MS method in use in the lab (the R(2) between the two methods was 0.9951).