Evaluation of Ethanol and N-propanol in Victims

Background: Blood alcohol concentration is a major factor in forensic analysis in criminal and civil litigation. Along with ethanol, other volatile compounds such as n-propanol are produced as products of putrefaction. The aim of this study is the evaluation of ethanol and n-propanol in postmortem blood. Methods: A case-control study was done on 300 blood samples obtained from cadavers that were referred to Legal Medicine Organization (LMO) of Tehran, Iran, over a year (2009-2010). Blood ethanol and n-propanol concentrations were analyzed in duplicate by HSGC. Data on cadavers were taken from the information sheets and were analyzed by SPSS software. Results: In this study, mean n-propanol level in blood was 8.311 mg/dl in putrefied and 1.58 mg/dl in non-putrefied victims. Interval times between death and autopsy in putrefied and non-putrefied victims were 3.5 and 1.25 days. Results show that n-propanol concentrations increase 1.23 mg/dl/day after death. In 99% of putrefied victims, ethanol level was more than 10 mg/dl. There was a high correlation between ethanol and n-propanol concentrations. By increasing 1mg/dl of n-propanol concentration, ethanol levels increased 2.5 and 1.4 mg/dl in putrefied and non-putrefied victims, respectively. Conclusion: N-propanol produced in putrefied victims with ethanol. Production of ethanol increased by rising n-propanol levels. Therefore, we might use n-propanol as a putrefaction factor in postmortem blood to distinguish endogenous and exogenous ethanol production.