Multiple fatalities in the North of England associated with synthetic fentanyl analogue exposure: Detection and quantitation a case series from early 2017

Abstract

Background: Synthetic fentanyl analogues are highly potent opioid drugs which have no pharmaceutical use in humans. We detected the synthetic fentanyl analogues; carfentanil, butyryl fentanyl, fluorobutyrylfentanyl, furanylfentanyl, and alfentanil as well as fentanyl itself in 25 cases in early 2017. There have been no previous reports of synthetic fentanyl deaths in the United Kingdom (UK).

Methods: Cases in which the history clearly stated drug use but where a post mortem blood morphine concentration was lower than would be expected to explain the sudden death, were referred for further analysis by high resolution accurate mass (HRAM) mass spectrometry.

Results: 25 post mortem cases in which synthetic fentanyl analogues were implicated in the cause of death were reported from January to May 2017. No cases were seen in June 2017. The age range was 21-54 years and 22 were male. There was a history of heroin use, or markers of heroin use on toxicology screening in 21/25 cases. Carfentanil and fentanyl were detected in 7 cases. Multiple synthetic fentanyl analogues were present in 13 cases, with the remaining 5 cases having only carfentanil present. Synthetic fentanyl analogues were detected in combination with other drugs in all cases. Significant concentrations of ethanol were detected in only 2 cases. The concentration range of carfentanil in blood was 90-4004pg/mL. Of note, the 3 cases in which ante mortem carfentanil was quantified ranged from 21 to 98pg/mL. In all cases, death was attributed to combined central nervous system depression.

Conclusions: This paper highlights a new and rapid emergence of these drugs into the UK illicit drug arena. Synthetic fentanyl analogues represent a significant challenge both analytically and clinically within the groups who misuse drugs. It is worthwhile considering the possibility of the presence of these drugs in cases in which a toxicological cause of death is not apparent analytically but there is a history of drug use and circumstantial evidence exists to support a drug-related death as the most likely cause. It may be that synthetic fentanyl analogues should be screened for routinely to avoid reporting any false negative results, but the cost implications and viability of this have not been fully evaluated.

Keywords: Carfentanil; Fentanyl; Post mortem; Synthetic fentanyl analogues; Toxicology.