A 10 year post-mortem analysis of keratin matrix in Perugia (Italy): focus on cocaine involvement in several types of death

The use of keratin matrix, in detecting drug consumption, offers compelling advantages compared to other conventional biological matrices used for these types of investigation, and provides important information to surveys which are characterised by a general underestimation, especially in Italy. In our study we collected and analysed 424 hair samples from corpses autopsied in Perugia from January 2001 to December 2011 in order to detect traces of drugs and especially of cocaine, and evaluate their involvement in several types of death. Hair samples were analysed by gas chromatography–mass spectrometry in the Laboratory of Forensic Toxicology of the Department of Legal Medicine of the University of Perugia: 232 samples derived from cases of overdose deaths; 192 were connected to different causes of death. The average concentration of cocaine in the keratin matrix samples was of 3.74 ng/mg in people who died from overdose, 3.09 ng/mg in people who died from other causes. In 232 cases of overdose deaths, 135 were positive for cocaine (accounting for 58.18% of total); in 192 deaths from other causes, 39 were positive for cocaine (accounting for 20.31% of the total). Our study demonstrated the crucial role of cocaine in overdose deaths and in other deaths, as is well known in other research.