Preanalytical variables affecting the quantification of fatty acid ethyl esters in plasma and serum samples.

BACKGROUND Fatty acid ethyl esters (FAEEs) are cytotoxic nonoxidative ethanol metabolites produced by esterification of fatty acids and ethanol. FAEEs are detectable in blood up to 24 h after ethanol consumption. The objective of this study was to assess the impact of gender, serum or plasma triglyceride concentration, time and temperature of specimen storage, type of alcoholic beverage ingested, and the rate of ethanol consumption on FAEE concentrations in plasma or serum. METHODS For some studies, subject were recruited volunteers; in others, residual blood samples after ethanol quantification were used. FAEEs were isolated by solid-phase extraction and quantified by gas chromatography-mass spectrometry. RESULTS For weight-adjusted amounts of ethanol intake, FAEE concentrations were twofold greater for men than women (P /=24 h. The type of alcoholic beverage and rate of consumption did not affect FAEE concentrations. CONCLUSION These studies advance plasma and serum FAEE measurements closer to implementation as a clinical test for ethanol intake.