Test Catalog

Test Id : PETH

Phosphatidylethanol Confirmation, Blood

Useful For
Suggests clinical disorders or settings where the test may be helpful

Verifying abstinence or use of ethanol especially in liver transplant candidates/patients

Method Name
A short description of the method used to perform the test

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Phosphatidylethanol Confirmation, B

Lists additional common names for a test, as an aid in searching

1-Palmitoyl-2-linoleoyl-sn-glycero-3-phosphoethanol (PLPEth)

1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanol (POPEth)

Specimen Type
Describes the specimen type validated for testing

Whole Blood EDTA

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Container/Tube: Lavender top (EDTA)

Specimen Volume: 1 mL

Collection Instructions:

1. Do not centrifuge.

2. Send whole blood specimen in original tube. Do not aliquot.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.5 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross lipemia OK
Gross icterus OK

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Whole Blood EDTA Frozen (preferred) 28 days
Refrigerated 14 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Verifying abstinence or use of ethanol especially in liver transplant candidates/patients

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Phosphatidylethanol (PEth) is a direct biomarker for alcohol (ethanol) intake. In presence of ethanol, phosphatidylcholine is converted to PEth on the red blood cell membrane by the phospholipase D enzyme. PEth homologues (16:0/18:1 [POPEth: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanol] and 16:0/18:2 [PLPEth: 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphoethanol]) levels correlate with the amount of alcohol consumed within the previous 2 weeks and may be detected in the blood up to 2 to 4 weeks after excessive alcohol consumption. POPEth and PLPEth comprise approximately 60% of all observed PEth homologues in the blood.(1)

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

Negative (<10 ng/mL)


PEth 16:0/18:1 (POPEth): Lower limit of quantification =10 ng/mL

PEth 16:0/18:2 (PLPEth): Lower limit of quantification =10 ng/mL

Provides information to assist in interpretation of the test results

POPEth (1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanol):

A result of 20 ng/mL to 200 ng/mL is considered evidence of moderate ethanol consumption, while results over 200 ng/mL indicate heavy ethanol consumption. However, the Center for Substance Abuse Treatment advises caution in interpretation and use of biomarkers alone to assess alcohol use. Results should be interpreted in the context of all available clinical and behavioral information.(2)


PLPEth (1-Palmitoyl-2-linoleoyl-sn-glycero-3-phosphoethanol):

There are no current clinical reference limits for this phosphatidylethanol (PEth) homologue.


PEth 16:0/18:1 (POPEth)

Less than 10 ng/mL: Not detected

10-19 ng/mL: Abstinence or light alcohol consumption (<2 drinks per day for several days a week)

20-200 ng/mL: Moderate alcohol consumption (up to 4 drinks per day for several days a week)

Greater than 200 ng/mL: Heavy alcohol consumption or chronic alcohol use (at least 4 drinks per day several days a week)


PEth 16:0/18:2 (PLPEth): Reference ranges are not well established.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

No significant cautionary statements

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Helander A, Zheng Y: Molecular species of the alcohol biomarker phosphatidyethanol in human blood measured by LC-MS. Clin Chem. 2009 Jul:55:(7):1395-1405. doi: 10.1373/clinchem.2008.120923

2. Substance Abuse and Mental Health Services Administration (SAMHSA) and National Institute on Alcohol Abuse and Alcoholism: Medication for the Treatment of Alcohol Use Disorder: A Brief Guide. HHS Publication No. (SMA) 15-4907. SAMHSA; 2015.

3. Ulwelling W, Smith K: The PEth blood test in the security environment: What it is; why it is important; and interpretative guidelines. J Forensic Sci. 2018 Nov;63(6):1634-1640. doi: 10.1111/1556-4029.13874

4. Hakim F, Wiart JF, Menard O, Allorge D, Gaulier JM. Dosage sanguin du phosphatidylethanol Phosphatidylethanol blood analysis. Ann Biol Clin (Paris). 2019 Dec 1;77(6):638-644. French. doi: 10.1684/abc.2019.1499

Method Description
Describes how the test is performed and provides a method-specific reference

The received whole blood sample is diluted and mixed with internal standard and clinical laboratory reagent water and extracted using supported liquid extraction and analyzed by an in-house developed liquid chromatography-tandem mass spectrometry method.(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

2 to 7 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their account representative. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


G0480 (if appropriate)

LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
PETH Phosphatidylethanol Confirmation, B 101506-4
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
617481 PEth 16:0/18:1 (POPEth) by LC-MS/MS 97607-6
617482 PEth 16:0/18:2 (PLPEth) by LC-MS/MS 97606-8
617483 PEth Interpretation 59462-2

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports

Test Update Resources

Change Type Effective Date
New Test 2022-09-15