Ethanol as a recreational and social drug has been ingested by the human species for millennia. With its use comes the risk of addiction, due to genetic, mental, physical, and/or situational factors. In cases of abuse, individuals may refer to rehabilitation programs to receive support and help to quit using. Often a "no tolerance" policy may be enforced as part of the treatment. Random urine spot checks ensure compliance.
Ethanol analyte testing works well for recent ingestion (under 12 h); however, rehabilitation stays can easily exceed this window. A metabolite that remains in the body for an extended period of time (1-3 days) is ideal for monitoring a multi-day treatment cycle.
This assay instead analyzes the minor metabolites of ethanol: ethyl sulfate and ethyl glucuronide. The trace concentrations found in the body after ethanol ingestion are ideal for analysis by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The levels found in urine, as well as the window of excretion (typically at least a day from as little as a 1 oz drink) are quite similar to drugs of abuse, and thus can be reported and interpreted in a similar manner.