Phosphatidylethanol (PEth) in blood – Direct marker for Alcohol Detection

Phosphatidylethanol in Blood (PEth) is a stable, highly specific and sensitive marker for detecting chronic excessive drinking behaviour with a regular daily alcohol intake. 

  • PEth is found to be detectable in blood up to 28 days without alcohol.
  • Sex, age, gender and body mass do not influence the normalisation rate of PEth.
  • In comparison to serum CDT, PEth appears more sensitive.
  • CDT is an indirect marker, PEth is a DIRECT marker.
  • 99% clinical specificity when differentiating between abstainer and non-abstainer.


Neither CDT or PEth have established legal cut off values.


TestCodeSample TypeTurnaround Time
Results show: Any drinking > 35 ug/L
Regular excessive drinking > 210 ug/L
PETH A EDTA Whole Blood (do not separate)
OR A TDL Tiny™
5-7 days


Alcohol Profiles

TestCodeSample TypeTurnaround Time
Alcohol Profile 1 
LFT, Alcohol Level, CDT and MCV – now includes PEth
AP G 5-7 days
Alcohol Profile 2 
LFT, Alcohol Level, CDT, MCV, Urine Ethyl Gluconaride/Ethyl Sulfate –
now includes PEth 
  G RU 5-7 days