Diagnostic performance of ethyl glucuronide in hair for the investigation of alcohol drinking behavior: a comparison with traditional biomarkers

Background: Ethyl glucuronide (EtG) in hair has emerged as a useful biomarker for detecting alcohol abuse and monitoring abstinence. However, there is a need to establish a reliable cutoff value for the detection of chronic and excessive alcohol consumption. Methods: One hundred and twenty-five subjects were classified as teetotalers, low-risk drinkers, at-risk drinkers, or heavy drinkers. The gold standard for subjects' classifications was based on a prospective daily alcohol self-monitoring log. Subjects were followed for a 3-month period. The EtG diagnostic performance was evaluated and compared with carbohydrate-deficient transferring (CDT) and the activities of aspartate aminotransferase, alanine aminotransferase, and γ-glutamyl-transferase (γGT). Results: A cutoff of >9pg/mg EtG in hair, suggesting an alcohol consumption of >20/30g (at-risk drinkers), and a cutoff of >25pg/mg, suggesting a consumption of >60g (heavy drinkers), were determined by receiver operating characteristic analysis. The EtG diagnostic performance was significantly better (P < 0.05) than any of the traditional biomarkers alone. EtG, as a single biomarker, yielded a stronger or similar diagnostic performance in detecting at-risk or heavy drinkers, respectively, than the best combination of traditional biomarkers (CDT and γGT). The combination of EtG with traditional biomarkers did not improve the diagnostic performance of EtG alone. EtG demonstrated a strong potential to identify heavy alcohol consumption, whereas the traditional biomarkers failed to do so. EtG was not significantly influenced by gender, body mass index, or age. Conclusion: Hair EtG definitively provides an accurate and reliable diagnostic test for detecting chronic and excessive alcohol consumption. The proposed cutoff values can serve as reference for future cutoff recommendations for clinical and forensic us

Codeine accumulation and elimination in larvae, pupae, and imago of the blowfly Lucilia sericata and effects on its development

The aim of this study was to evaluate the reliability of insect larvae as samples for toxicological investigations. For this purpose, larvae of Lucilia sericata were reared on samples of minced pig liver treated with different concentrations of codeine: therapeutic, toxic, and potentially lethal doses. Codeine was detected in all tested larvae, confirming the reliability of these specimens for qualitative toxicology analysis. Furthermore, concentrations measured in larvae were correlated with levels in liver tissue. These observations bring new elements regarding the potential use of opiates concentrations in larvae for estimation of drug levels in human tissues. Morphine and norcodeine, two codeine metabolites, have been also detected at different concentrations depending on the concentration of codeine in pig liver and depending on the substance itself. The effects of codeine on the development of L. sericata were also investigated. Results showed that a 29-h interval bias on the evaluation of the larval stage duration calculated from the larvae weight has to be considered if codeine was present in the larvae substrate. Similarly, a 21-h interval bias on the total duration of development, from egg to imago, has to be considered if codeine was present in the larvae substrat

Positive EtG findings in hair as a result of a cosmetic treatment

In a case of a driving ability assessment, hair analysis for ethyl glucuronide (EtG) was requested by the authorities. The person concerned denied alcohol consumption and did not present any clinical sign of alcoholism. However, EtG was found in concentrations of up to 910pg/mg in hair from different sampling dates suggesting an excessive drinking behavior. The person declared to use a hair lotion on a regularly base. To evaluate a possible effect of the hair lotion, prospective blood and urine controls as well as hair sampling of scalp and pubic hair were performed. The traditional clinical biomarkers of ethanol consumption, CDT and GGT, were inconspicuous in three blood samples taken. EtG was not detected in all collected urine samples. The hair lotion was transmitted to our laboratory. The ethanol concentration in this lotion was determined with 35g/L. The EtG immunoassay gave a positive result indicating EtG, which could be confirmed by GC-MS/MS-NCI. In a follow-up experiment the lotion was applied to the hair of a volunteer over a period of six weeks. After this treatment, EtG could be measured in the hair at a concentration of 72pg/mg suggesting chronic and excessive alcohol consumption. Overnight incubation of EtG free hair in the lotion yielded an EtG concentration of 140pg/mg. In the present case, the positive EtG hair findings could be interpreted as the result of an EtG containing hair care product. To our knowledge, the existence of such a product has not yet been reported, and it is exceptionally unusual to find EtG in cosmetics. Therefore, external sources for hair contamination should always be taken into account when unusual cosmetic treatment is mentioned. In those cases, it is recommended to analyze the hair product for a possible contamination with EtG. The analysis of body hair can help to reveal problems occurring from cosmetic treatment of head hair. As a consequence, the assessment of drinking behavior should be based on more than one diagnostic parameter

Development and validation of a gas chromatography-negative chemical ionization tandem mass spectrometry method for the determination of ethyl glucuronide in hair and its application to forensic toxicology.

Ethyl glucuronide (EtG) is a minor and direct metabolite of ethanol. EtG is incorporated into the growing hair allowing retrospective investigation of chronic alcohol abuse. In this study, we report the development and the validation of a method using gas chromatography-negative chemical ionization tandem mass spectrometry (GC-NCI-MS/MS) for the quantification of EtG in hair. EtG was extracted from about 30 mg of hair by aqueous incubation and purified by solid-phase extraction (SPE) using mixed mode extraction cartridges followed by derivation with perfluoropentanoic anhydride (PFPA). The analysis was performed in the selected reaction monitoring (SRM) mode using the transitions m/z 347--&gt;163 (for the quantification) and m/z 347--&gt;119 (for the identification) for EtG, and m/z 352--&gt;163 for EtG-d(5) used as internal standard. For validation, we prepared quality controls (QC) using hair samples taken post mortem from 2 subjects with a known history of alcoholism. These samples were confirmed by a proficiency test with 7 participating laboratories. The assay linearity of EtG was confirmed over the range from 8.4 to 259.4 pg/mg hair, with a coefficient of determination (r(2)) above 0.999. The limit of detection (LOD) was estimated with 3.0 pg/mg. The lower limit of quantification (LLOQ) of the method was fixed at 8.4 pg/mg. Repeatability and intermediate precision (relative standard deviation, RSD%), tested at 4 QC levels, were less than 13.2%. The analytical method was applied to several hair samples obtained from autopsy cases with a history of alcoholism and/or lesions caused by alcohol. EtG concentrations in hair ranged from 60 to 820 pg/mg hair