Evaluation of ethylglucuronide and cocaethylene as hair markers of alcohol consumption

Background and aims: The concurrent use of alcohol and cocaine is known to be a harmful condition in terms of behaviour and organ damage. The identification of this condition requires the use of objective biomarkers, such as hair ethylglucuronide (hEtG) and hair cocaethylene (hCE). The aim of the present work was to investigate their presence and their possible mutual relationship in a group of cocaine users to evaluate the different potentials offered by the two analytes in the retrospective investigation of alcohol intake. Materials and methods: 209 hair specimens, previously collected from cocaine users in the context of re-issuing of the driving license, were analysed for the presence of CE and EtG. Results: Out of the 108 individuals who tested positive for hCE, only 57 resulted also positive for hEtG (52.8 %) (above our limit of quantification, i.e. 0.05 ng/mg for the former and 3 pg/ mg for the latter). Conversely, in a group of 101 hCE negative, 63 samples tested hEtG positive (62.4 %). Conclusions: the observed findings highlighted the advantage, in terms of improvement of diagnostic sensitivity, of an integrated use of the two metabolites for a reliable investigation strategy based on alcohol hair markers.