Alcohol markers in hair: an issue of interpretation

  • Richard PaulEmail author


Ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEEs) are metabolites of alcohol that when detected in hair can provide evidence of a person’s drinking behavior. The analysis of these compounds in hair has become commonplace in recent years and has been used as evidence in legal proceedings. Despite the routine use of such toxicological analysis, the correct interpretation of alcohol biomarker hair testing can be complex, and there may be debate as to the significance of the data. This paper considers whether the accepted norm of applying interpretative cut-off values to EtG and FAEE concentrations from hair samples is appropriate, and asks whether Bayesian theory, using a likelihood ratio approach may offer greater insight as to the strength of evidence. In addition to the complexity of result interpretation in this field, the sensitivity of alcohol biomarkers in hair to distinguish low level drinking from abstinence also represents a significant challenge. The use of fingernail EtG testing as an alternative to hair analysis is explored in this paper and it is proposed that fingernails may in theory show a higher uptake of EtG than hair, and thus show potential as a useful alternative matrix to document long-term low to moderate alcohol consumption.


Ethyl glucuronide Fatty acid ethyl esters Hair Fingernails Likelihood ratio Bayesian 



We acknowledge funding for part of this work from the Royal Society of Chemistry (RF18-8876).

Compliance with ethical standards

Conflict of interest

The author declares no conflict of interest.

Ethical approval

Bournemouth University ethics committee provided ethical approval for the work on ethyl glucuronide in fingernails.

Informed consent

The author declares that informed consent was sought from all participants relating to this work.


  1. 1.
    Pragst F, Balikova MA. State of the art in hair analysis for detection of drug and alcohol abuse. Clin Chim Acta. 2006;370:17–49.CrossRefGoogle Scholar
  2. 2.
    Pragst F. Interpretation problems in a forensic case of abstinence determination using alcohol markers in hair. Forensic Sci Int. 2012;10(217):1–3.Google Scholar
  3. 3.
    Society of Hair Testing: 2016 consensus for the use of alcohol markers in hair for assessment of both abstinence and chronic excessive alcohol consumption. Accessed 27 June 2018.
  4. 4.
    Bossers LCAM, Paul R. Application of Bayesian theory to the reporting of results in alcohol hair testing. Forensic Sci Int. 2014;242:e56–8.CrossRefGoogle Scholar
  5. 5.
    Alladio E, Martyna A, Salomone A, Pirro V, Vincenti M, Zadora G. Evaluation of direct and indirect ethanol biomarkers using a likelihood ratio approach to identify chronic alcohol abusers for forensic purposes. Forensic Sci Int. 2017;271:13–22.CrossRefGoogle Scholar
  6. 6.
    Biedermann A, Taroni F, Bozza S, Augsburger M, Aitken CGG. Critical analysis of forensic cut-offs and legal thresholds: a coherent approach to inference and decision. Forensic Sci Int. 2018;288:72–80.CrossRefGoogle Scholar
  7. 7.
    Cappelle D, Neels H, De Keukeleire S, Fransen E, Dom G, Vermassen A, et al. Ethyl glucuronide in keratinous matrices as biomarker of alcohol use: a correlation study between hair and nails. Forensic Sci Int. 2017;279:187–91.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Faculty of Science and TechnologyBournemouth UniversityPooleUK

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