Giovanna Tassoni

Polydrug use is a frequent pattern of consumption in Europe. This behavior has mainly been analyzed within restricted groups; more rarely in large populations. Current polydrug use is less studied than simultaneous use. This study focused on the concurrent assumption of polydrug among drivers using hair matrix. Hair matrix, for its biological characteristics, allows to identify illicit drug use more often than other matrices, i.e., urine, and it provides information on the long-term use of them. Hair samples of subjects positive for opiates, cocaine and delta-9-tetrahydrocannabinol (Δ⁹-THC) collected by the forensic toxicology laboratory of the University of Macerata in the period 2010–2020, were analyzed using a gas chromatography-mass spectrometry method. Our results evidenced that a significant part of the examined population (12.15%) used polydrug. A strong predominance of males over females was evident. Polydrug users were more frequently young people. The abuse of two substances was predominant. Cocaine and Δ⁹-THC was the most common combination, followed by cocaine and morphine, and morphine and Δ⁹-THC. The timeframe of polydrug use was also analyzed. Our study shows that polydrug use is a very frequent behavior, and that hair analysis may be a powerful tool to obtain objective biological information of this complex phenomenon.

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.

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.

Following its metabolism in the liver, morphine and its metabolites can be directly eliminated in bile. Then, they undergo the enterohepatic cycle (EHC) and mostly reappear in the circulation. We report a case showing the presence of morphine in bile (21.3 mug/mL) and hair (4.8 ng/mg) but not in blood, urine or the liver of an addict who survived in hospital for about 144 h (6 days). These data would indicate that the EHC does not play any role about 144 h after the last injection, and directly confirms that gall bladder is a storage depot for morphine. They constitute the first report of a demonstration of the effect of the EHC on morphine bioavailability in an addict, and could be considered as indication, without supporting circumstantial evidence, that the morphine level in bile is related to chronic opiate use.

This study reports the results of the retention and quantitation of barbiturates in fresh tissue, in liver tissue fixed in formalin, and in the formalin solutions in which the same tissues were fixed for six months. Biological materials came from four cases of death due to phenobarbital and two due to butalbital. Results showed the presence of barbiturates in all studied materials. Mean recovery rates of phenobarbital in fixed liver were 57.11% and 30.84% in formalin from liver; and those of butalbital in fixed liver were 21.66% and 66.56% in formalin from liver. Total sums of recovery rates in formalin solutions and fixed tissues for phenobarbital (87.95%) and butalbital (88.22%) were comparable with those of the extraction efficiency of the method (90.2%) and indicate that these barbiturates have good stability even in biological specimens subjected to chemical fixation. This fact may be useful in qualitative evaluation of cases.

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.