Ethanol Metabolites: Their Role in the Assessment of Alcohol Intake

BACKGROUND Alcohol-related disorders are common, expensive in their course, and often underdiagnosed. To facilitate early diagnosis and therapy of alcohol-related disorders and to prevent later complications, questionnaires and biomarkers are useful. METHODS Indirect state markers like gamma-glutamyl-transpeptidase, mean corpuscular volume, and carbohydrate deficient transferrin are influenced by age, gender, various substances, and nonalcohol-related illnesses, and do not cover the entire timeline for alcohol consumption. Ethanol (EtOH) metabolites, such as ethyl glucuronide, ethyl sulfate, phosphatidylethanol, and fatty acid ethyl esters have gained enormous interest in the last decades as they are detectable after EtOH intake. RESULTS For each biomarker, pharmacological characteristics, detection methods in different body tissues, sensitivity/specificity values, cutoff values, time frames of detection, and general limitations are presented. Another focus of the review is the use of the markers in special clinical and forensic samples. CONCLUSIONS Depending on the biological material used for analysis, ethanol metabolites can be applied in different settings such as assessment of alcohol intake, screening, prevention, diagnosis, and therapy of alcohol use disorders.