Mayo Clinic Laboratories has developed a new direct biomarker test for alcohol consumption called Phosphatidylethanol Confirmation, Blood (Mayo ID: PETH). This blood test has a much longer detection window than existing urine tests for alcohol use.

The preferred screening approach for ethanol, the chemical term for alcohol, measures certain substances that the body produces when ethanol is metabolized. The direct ethanol metabolites (i.e., ethyl glucuronide and ethyl sulfate) currently used for alcohol testing can be detected in urine for up to five days.

PETH measures a different alcohol metabolite, known as phosphatidylethanol (PEth), in whole blood, providing a window of detection of approximately two to four weeks. The window can be even longer in individuals who chronically or excessively consume alcohol.

To learn more, check out this episode of the “Answers From the Lab” podcast on Mayo Clinic Laboratories Insights.