The Role of Alcohol Biomarkers in Family Law

Understanding Alcohol Testing in Legal Contexts

In family law proceedings, alcohol testing plays a vital role in ensuring fair and informed decisions. From custody disputes to compliance monitoring, understanding how alcohol biomarkers function can provide clarity in complex cases. Key biomarkers like PEth, ETG, and CDT offer insight into drinking patterns, ranging from chronic excessive consumption to occasional social drinking. This blog explores these biomarkers and illustrates their application using the example of Mark and Tiki, two fictional drinkers with contrasting habits.

Breaking Down Alcohol Biomarkers

1. PEth (Phosphatidylethanol)

PEth is a direct alcohol biomarker formed only in the presence of ethanol. It stands out for its:

• Detection Window: Up to four weeks (up to 1 month), making it ideal for monitoring recent alcohol consumption.

• Accuracy: Minimally influenced by external factors like medication or most of the medical conditions.

• Sample Collection: Requires very small amount of blood(1 blood drop through a finger prick sampling), ensuring ease and compliance.

2. ETG (Ethyl Glucuronide)

ETG is commonly detected in hair or nails, providing a longer-term view of alcohol consumption:

• Detection Window: Spanning several months in hair or weeks in urine.

• Application: Useful in cases requiring historical drinking patterns.

• Limitations: Can be influenced by external hair treatments like bleaching.
  
  

3. EtPa (Ethyl Palmitate)

Ethyl Palmitate

• Detection Window: EtPa, which is also known as FAEE, is a biomarker used to indicate recent typically reflecting alcohol use within the past few months if tested in hair or nails.

• Applications: EtPa is often used in forensic toxicology and family law cases to provide evidence of historic alcohol use. Less impacted by external treatments such as hair dye and bleach. 

• Limitations: EtPa is susceptible to environmental contamination due to the presence of ethanol in common products such as hair sprays, potentially leading to false-positive results.

4. CDT (Carbohydrate-Deficient Transferrin)

CDT is an indirect biomarker reflecting chronic excessive alcohol use:

• Detection Window: Two to four weeks.

• Influences: Affected by conditions such as hormonal variation and smoking, potentially leading to false positives.

• Use Case: Best for identifying chronic excessive drinking behavior.

Mark vs. Tikki: A Tale of Two Drinkers

 

To illustrate how alcohol biomarkers are applied in family law, let’s meet Mark and Tiki:

Mark: The Chronic Excessive Drinker

Mark consumes approximately eight alcohol units daily, exceeding the threshold for excessive drinking (7.5 units for men). Testing reveals:

• CDT Levels: Elevated, indicating prolonged heavy drinking.

• PEth Results: High, confirming recent alcohol use.

• Hair Testing: Shows sustained alcohol consumption over several months.

These findings could be pivotal in custody cases, signaling potential concerns about his ability to provide a stable environment.

Tikki: The Reformed Drinker

Tiki used to be a big drinker for decades. Now she has it under control and drinks three units per day, well below the threshold for excessive drinking (5 units for women). Her test results highlight:

• CDT Levels: High, reflecting an excessive alcohol intake.

• PEth Results: Low, affirming her claims of occasional drinking.

• Hair Testing: Minimal markers, consistent with social drinking habits.

For Tikki, you can see that there is an incongruence in her results. This is because CDT is not an accurate biomarker for people with a history of chronic excessive drinking. CDT can be detected for a longer period after alcohol consumption has decreased. CDT could also be affected by some of the medical conditions and social habits of Tikki. Thankfully, in this case the PEth and Hair results tell a different story. Thanks to these tests, Tikki can relax that her history hasn’t come back to haunt her.

Tailoring Testing to Case Needs

The choice of alcohol testing methods depends on the specific requirements of the case. PEth testing is often preferred for its accuracy and non-invasive collection process which can show any alcohol consumption for a month while ETG offers complementary insights into long-term drinking and EtPa acts as supporting evidence to the EtG findings especially if the hair has been chemically treated such as bleached or dyed.  By combining these methods, legal professionals can build a robust understanding of an individual’s alcohol consumption patterns.

Closing Thoughts: Leveraging Biomarkers for Fair Outcomes

Accurate alcohol testing is essential in family law to ensure equitable decisions that prioritise the well-being of all parties involved. Biomarkers like PEth, ETG, EtPa and CDT provide powerful tools for assessing drinking behaviors and their potential impact. By understanding these methods and tailoring them to case needs, legal professionals can confidently navigate the complexities of alcohol-related evidence.

For more information, get in touch with our team today!

 

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