Phosphatidylethanol (PEth) is a specific or direct alcohol biomarker, which forms only in the presence of ethanol. It is a more sensitive indicator than the indirect markers of CDT, LFT and FBE (these can be influenced by other health issues and medication).
PEth indicates levels of alcohol consumption over a period up to 28 days. PEth is eliminated from the body in approximately 30 days, meaning the window of detection is often given as one month.
PEth enables the discrimination of heavy versus moderate or occasional drinkers and can monitor abstinence. Age, gender, health or previous alcohol issues do not impact the results.
A sample of blood is collected via a finger prick using a convenient and compact device, enabling collection of a dried blood spot for analysis by the laboratory. The dried blood spot is stable for a long period of time and no special transport or storage is required.
The ability of a PEth test to discriminate between heavy, moderate and minimal alcohol consumption is a key benefit of the test.
Abstinence or irregular low alcohol consumption in the approximate month prior to the sample collection.
PEth between 20 – 200ng/mL:
Consistent with alcohol consumption, but not at an excessive level, in the approximate month prior to the sample collection.
PEth >200 ng/mL:
Excessive alcohol consumption in the approximate month prior to the sample collection.
NOTE: There are a number of factors that affect the level of PEth, for example, differences in metabolism and frequency of alcohol consumption. The consumption of a higher number of drinks on one occasion will produce a higher blood alcohol concentration and consequently a higher PEth result than if the same number of drinks were consumed on five separate occasions. It can take a number of weeks following abstinence from alcohol for all PEth to be eliminated, depending on the original increase in the PEth level that existed for that individual.
Collection of both a blood sample for PEth and a hair sample for EtG can complement each other and show comparisons or differences between recent and long-term alcohol use.
Samples for PEth testing are sent to Cansford Laboratories with results returned with 1 – 2 weeks of sample collection. See Cansford’s blog for further information about PEth.