Formation of Phosphatidylethanol and Its Subsequent Elimination During an Extensive Drinking Experiment Over 5 Days

Background For almost 30years, phosphatidylethanol (PEth) has been known as a direct marker of alcohol consumption. This marker stands for consumption in high amounts and for a longer time period, but it has been also detected after 1 high single intake of ethanol (EtOH). The aim of this study was to obtain further information about the formation and elimination of PEth 16:0/18:1 by simulating extensive drinking. Methods After 3weeks of alcohol abstinence, 11 test persons drank an amount of EtOH leading to an estimated blood ethanol concentration of 1g/kg on each of 5 successive days. After the drinking episode, they stayed abstinent for 16days with regular blood sampling. PEth 16:0/18:1 analysis was performed using liquid chromatography-tandem mass spectrometry (high-performance liquid chromatography 1100 system and QTrap 2000 triple quadrupole linear ion trap mass spectrometer. Values of blood alcohol were obtained using a standardized method with headspace gas chromatography flame ionization detector. Results Maximum measured concentrations of EtOH were 0.99 to 1.83g/kg (mean 1.32g/kg). These values were reached 1 to 3hours after the start of drinking (mean 1.9hours). For comparison, 10 of 11 volunteers had detectable PEth 16:0/18:1 values 1hour after the start of drinking, ranging from 45 to 138ng/ml PEth 16:0/18:1. Over the following days, concentrations of PEth 16:0/18:1 increased continuously and reached the maximum concentrations of 74 to 237ng/ml between days 3 and 6. Conclusions This drinking experiment led to measurable PEth concentrations. However, PEth 16:0/18:1 concentrations stayed rather low compared with those of alcohol abusers from previous studies.