GC-MS and GC-MS/MS in PCI mode determination of mescaline in peyote tea and in biological matrices.

Peyote, a cactus containing the hallucinogen mescaline, is used to induce altered states of consciousness in religious ceremonies or for recreational purpose. This study reports a case of an underage boy suspected of mescaline abuse. For this purpose, we analyzed a dark green liquid sample found in the bedroom of the boy whose urine and hair samples were collected shortly after the drink was found. A method by gas chromatography-mass spectrometry tandem mass spectrometry (GC-MS/MS) in positive chemical ionization mode was developed and validated in terms of linearity, specificity, accuracy, and sensitivity for mescaline determination at the low concentrations present in hair. GC-MS analysis of the liquid identified mescaline, while urine was negative; GC-MS/MS segmental hair analysis identified mescaline in the proximal segment (root to 2 cm), while the distal segments were negative. Although peyote was uncommonly encountered, its use was confirmed by segmental hair analysis that can provide long-term information about drugs use.