Ordering Recommendation

Biomarker associated with ethanol consumption; may be helpful in monitoring alcohol abstinence.




Quantitative Liquid Chromatography-Tandem Mass Spectrometry




1-4 days

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation

Lavender (K2 or K3 EDTA), Pink (K2EDTA), Green (lithium heparin), or Gray (potassium oxalate).

Specimen Preparation

Transport 1 mL whole blood. (Min: 0.5 mL)

Storage/Transport Temperature

Refrigerated. Also acceptable: Frozen.

Unacceptable Conditions

Gel separator tubes, Plain Red, light blue (citrate), or yellow (SPS or ACD solution).


Ambient: 2 hours; Refrigerated: 2 weeks; Frozen: 1 month (-20°C)

Reference Interval

Effective September 8, 2020

By Report

Interpretive Data

Phosphatidylethanol (PEth) is a group of phospholipids formed in the presence of ethanol, phospholipase D and phosphatidylcholine. PEth is known to be a direct alcohol biomarker. The predominant PEth homologues are PEth 16:0/18:1 (POPEth) and PEth 16:0/18:2 (PLPEth), which account for 37-46% and 26-28% of the total PEth homologues, respectively. PEth is incorporated into the phospholipid membrane of red blood cells and has a general half-life of 4 - 10 days and a window of detection of 2 - 4 weeks. However, the window of detection is longer in individuals who chronically or excessively consume alcohol. Serial monitoring of PEth may be helpful in monitoring alcohol abstinence over time.  PEth results should be interpreted in the context of the patient's clinical and behavioral history.  Patients with advanced liver disease may have falsely elevated PEth concentrations (Nguyen VL et al 2018, Alcoholism Clinical & Experimental Research).

Compliance Category

Laboratory Developed Test (LDT)


Hotline History


CPT Codes

80321 (Alt code: G0480)


Component Test Code* Component Chart Name LOINC
3002599 PEth 16:0/18:2 (PLPEth) 97606-8
3002600 PEth 16:0/18:1 (POPEth) 97607-6
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • 1,2-dioleoyl-sn-glycero-3-phosphoethanol
  • 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanol
Phosphatidylethanol (PEth), Whole Blood, Quantitative