Understanding PEth: A Key Marker for Alcohol Consumption

Understanding Alcohol Consumption with PEth Testing

Phosphatidylethanol (PEth) is a critical biomarker for detecting alcohol consumption, providing valuable insights into an individual's drinking behaviour. Phosphatidylethanol (PEth) testing is a highly specific method for detecting alcohol consumption, providing a reliable marker of recent ethanol intake. PEth is a superior marker that is used in child custody cases and other legal cases to test participants for excessive alcohol misuse and complete abstinence (teetotalism), as mentioned by one of the leading medical journals (PubMed, 2018).

This article will explain PEth as an alcohol test, how it is formed, and why it is significant in various settings, including the legal sector.

What is PEth?

PEth is a group of direct alcohol biomarkers which, unlike certain other alcohol markers, are only formed in the human body when alcohol is present. It is tested in blood. Enzymes in the body transform components of biological cell membranes and these have been identified in human blood. The two most abundant analogues, often measured together, are PEth 16:0/18:1 and PEth 16:0/18:2. 

PEth Dection Window

“PEth blood test has a much longer window of detection than existing urine tests for alcohol use” (Mayo Clinic, 2024). PEth can serve as an indicator of alcohol consumption for approximately up to 4 weeks immediately before the sample collection.

Stability and Measurement of PEth

PEth is not stable in liquid blood unless stored at extremely low temperatures (-80ºC). Therefore, at AttoLife it is collected and measured using Dried Blood Spots (DBS), which offer better analyte stability. DBS involves sampling small volumes of blood (10-20 µL) on filter paper, which then dries. This method has several advantages over traditional venipuncture, including minimal invasiveness (e.g., a simple finger-prick).

Why PEth is a Reliable Marker

PEth is a direct metabolite of ethanol. This means that unlike the other alcohol markers in blood, it will only be detectable if alcohol was consumed. The reliability of PEth as a marker for alcohol consumption stems from its specificity and the low likelihood of false positives. Since PEth is only formed in the presence of ethanol, its detection directly indicates alcohol intake. This specificity makes it a highly trusted method for assessing recent alcohol use.

 

Classifying Drinking Habits with PEth

PEth levels help classify individuals into three categories based on their alcohol consumption:

• Abstinence: Below the lower threshold, indicating little to no alcohol consumption.
• Moderate Drinkers: Between the lower and upper thresholds, indicating moderate alcohol consumption.
• Excessive Consumers: Above the upper threshold, indicating excessive alcohol consumption.

These thresholds can vary, but they generally serve to distinguish between light, significant, and excessive alcohol use.

 

Applications of PEth Testing

PEth testing is widely used in several fields:

• Family Law: To assess parental fitness and ensure the safety and well-being of children. In family law and child custody cases phosphatidylethanol (PEth) has been proven to provide the most conclusive insight into a person’s drinking patterns (Johnson Astills, 2024).
• Organ Transplantation: To ensure that candidates maintain required sobriety levels for eligibility
• Medical Settings: To monitor alcohol consumption in patients undergoing treatment for alcohol dependency. 
• Legal and Regulatory Environments: For evaluating fitness for driving, granting gun licences, and other legal matters.

 

PEth Testing: A Summary

PEth testing provides a precise and reliable measure of alcohol consumption, making it invaluable in family law and child custody cases. By understanding PEth and its applications, we can better appreciate its role in monitoring and managing alcohol use for approximately one month, ultimately contributing to healthier and safer communities.

AttoLife UK Based in-house labs are equipped to meet your testing needs with reliability and expert support. Our Drug and alcohol tests are court approved. Please get in touch with our team for any enquiry about PEth testing, hair strand drug testing, nail drug testing, DNA testing or any other enquiries. 

If you are interested in obtaining a quote for PEth testing, please fill in our quote form and we will be right back to you.