Ethyl glucuronide in vitreous humor and blood postmortem specimens: analysis by liquid chromatography-electrospray tandem mass spectrometry and interpreting results of neo-formation of ethanol

Abstract

Introduction. The determination of ethyl glucuronide (EtG), a stable and sensitive

marker that is specific to alcohol intake, finds many applications both in the forensic

toxicology and clinical fields.

Aim. The aim of the study is to examine the possibility of using a cadaveric biological

matrix, vitreous humor (VH), to determine EtG as a marker of recent ethanol use.

Methods. The blood, taken from the femoral vein, and the VH were obtained from 63

autopsy cases. Analysis of the EtG was performed using an LC/MS/MS system. Analyses

of the ethanol and putrefaction biomarkers, such as acetaldehyde and n-propanol, were

performed using the HS-GC/FID technique in both the matrices.

Results. In 17 cases, both ethanol and EtG were absent in both matrices.Nineteen cases

presented ethanol in blood from 0.05 to 0.30 g/L, EtG-Blood concentration from 0.02

to 3.27 mg/L, and EtG-VH concentration from 0.01 mg/L to 2.88 mg/L. Thirteen cases

presented ethanol in blood > 0.05 g/L but EtG concentration in blood and VH lower

than 0.01 mg/L, are part of these 8 samples presented acetic aldehyde and n- propanol in

blood or VH, means identification of putrefaction indicators. Fourteen cases presented

ethanol in blood > 0.46 and EtG concentration in blood and VH higher than 0.01 mg/L.

Conclusions. The determination of EtG in biological material is important in those

cases where the intake of ethanol appears doubtful, as it allows us to exclude the possibility

of any post-mortem formation of ethanol.