An ocfentanil-related death case: UHPLC-MS analysis of the drug and its metabolites

OcF is a potent synthetic opioid, structurally analogue of fentanyl, abused as a new psychoactive substance in the recreational drug scenario. This work deals with a drug-related fatality involving OcF. In order to obtain a diagnosis of death, a forensic-based method involving anamnestic, clinical and circumstantial, anatomo-pathological and toxicological criteria was used. It was known that the deceased person had a substantial anamnestic history of drug addiction when in life, which may direct the diagnosis towards a death correlate with a chemical cause. As far as the anatomo-pathological findings are concerned, limbs lesions were found to be significant and consisted with a narcotic substance injection. Indeed, the toxicological investigations performed on the brown powder and subsequently on the biological specimens, taken from the body of the deceased person, has shown the presence of OcF in the femoral and cardiac blood, in urine, bile, brain, liver, lung and kidney, together with paracetamol and caffeine. To do this, an ultra-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS) based method was developed and validated for OcF quantitation and the simultaneous main metabolites identification. This represents the first reported case in Italy of a fatal outcome related to Ocf and the first time the drug is quantified in tissues. In addition, the toxicological data obtained in the present study, taken together with the well-known potency and danger of the substance and with the congruence between anamnestic, circumstantial and anatomopathological data with the hypothesis of acute narcosis, allow us to support the lethal power of OcF.