A forensic standard procedure is described that combines enzyme-linked immunoassay for screening and gas chromatography–mass spectrometry (GC–MS) for confirmation to detect drugs of abuse in a sample before used to detect opioids and cocaine. We used two equal aliquots of the same previously selected cannabinoid positive hair samples, one of which was subjected to acid hydrolysis. Afterward, both the aliquots were subjected to basic extraction and then to immunoassay screening. After derivatization, the GC–MS parameters were the same for both the aliquots for the determination of the cannabinoids (Δ⁹-tetrahydrocannabinol, cannabidiol and cannabinol). The results show that there were no statistical differences between the nonpreviously treated and the pretreated hair samples for the quantification of the three cannabis products for immunochemical procedure. No differences between the two groups were shown as for GC–MS confirmation procedures. All substances showed a good linearity between 0.05 and 2 ng/mg. The limit of detection ranged from 0.02 to 0.03 ng/mg, and the limit of quantification was 0.05 ng/mg for all substances. To our knowledge, this is the first time that screening and confirmation procedures have been applied on the same sample of hair to detect more than one drug of abuse.

This study reports the results of the detection and quantitation of cocaine and its metabolites in liver tissues fixed in formalin and in the formalin solutions in which the same tissues were fixed. Toxicological analyses were performed on formalin-fixed liver samples from four cases of death of cocaine abusers and on formalin solutions (10% buffered, pH 7) in which the samples were preserved. Analyses carried out at the time of autopsy on body fluids and tissues allowed identification of cocaine and the metabolite benzoylecgonine. Liver tissue samples were preserved in formalin solutions for four weeks before analysis. Results only showed the presence of benzoylecgonine in the studied materials. The mean levels of recovery of benzoylecgonine in fixed tissues were 12.31% in liver and 84.47% in formalin from liver. Results indicated that benzoylecgonine has good stability, even in biological specimens subjected to chemical fixation.

Taxus baccata is a widely distributed yew often associated with cases of fatal intoxication, which is related to the high amounts of cardiotoxic alkaloids, taxine A and taxine B, contained in its leaves. In this paper, a case of Taxus fatal poisoning, hypothesized by the forensic autopsy, has been confirmed by the application of both gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) techniques. A GC-MS method was used for the determination of the derivatized 3,5-dimethoxyphenol, a cyanogenic aglylactone considered as a marker of Taxus poisoning, being present in all species of Taxus. The detection by LC-MS-MS of taxine B and isotaxine B in the biological specimens confirmed the absorption of cardiotoxic alkaloids and allowed to established the cause of death as the ingestion of Taxus baccata leaves.