Detection of alcohol use: Guidance of direct biomarker phosphatidylethanol

Acknowledging the fact that alcohol is an important source of fatalities in traffic, the amount of alcohol consumed and the exact time of the consumption could enlighten forensic cases and guide the justice system correctly. However, determining the alcohol use is a difficult problem due to alcohol metabolism in individuals and parameters such as sex, age, amount of alcohol in the drink, satiety, should be taken into account which can be challenging for amount of alcohol interpretation. Considering that blood alcohol concentration (BAC) may not be reliable, alternative metabolic products of alcohol has arisen after alcohol consumption. One of the most interesting alcohol biomarker phosphatidylethanol (PEth) has caught attention due to its long half-life and not being affected from sex, liver diseases or age in addition to that it is only synthesized under the presence of ethanol. PEth is synthesized in cell-membranes and not being a single molecule, its homologues should be considered when determining the amount of alcohol intake. Although the homologues of PEth could be isolated from whole blood, less invasive dried blood spots (DBS) also provides reliable information. The analysis of PEth is performed in LC-MS/MS which is highly sensitive and specific. For forensic applications, direct alcohol biomarker PEth may be useful for distinguishing the alcohol use and helpful for justice system. This review focuses on studies about PEth biomarker, its applications and limitations conducted from 2010 to 2019.