Patterns of the most abundant volatiles detected in post-mortem blood

The most abundant volatiles detected during the forensic ethanol analysis are ethanol, acetaldehyde, 1-propanol, 2-propanol, and acetone. These volatiles could either be initiated in the human body after the consumption of alcoholic beverages; or have been produced ante mortem during metabolic processes or post-mortem by microbes. Aims of this study were the determination of the volatiles’ concentrations in autopsy blood samples received from 483 routinely autopsied corpses and classification of their patterns according to the manner of death, and the presence of putrefaction at autopsy. The volatiles concentrations were determined by a validated gas chromatographic method. The experimental values obtained from these determinations were submitted to statistical evaluation by principal component analysis (PCA). Blood acetaldehyde, acetone, 1and 2-propanol concentrations were higher in cases of violent and undetermined deaths compared to the ones determined in cases of natural deaths. Blood volatiles concentrations were dispersed in higher values in cases with putrefaction compared to cases without putrefaction at autopsy. Blood volatiles had low values in the majority of cases with low BAC. All volatiles had higher maximum concentrations and broader concentration ranges when BAC ranged from 10-100 mg/ dL. Cases of undetermined manner of death along with some cases of violent deaths achieved clustering (PCA) from cases of violent or natural manner of death indicating similarities among the grouped samples on the basis of measured blood 1-propanol and ethanol concentrations. The latter novel finding needs further investigation using a larger dataset pool and possibly other classification method with a different regression model.