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Luca Morini - One of the best experts on this subject based on the ideXlab platform.

  • Ethyl Glucuronide hair testing: A review.
    Forensic science international, 2019
    Co-Authors: Anna Biondi, Francesca Freni, Matteo Moretti, Claudia Carelli, Luca Morini
    Abstract:

    Abstract Ethyl Glucuronide (EtG) is a minor, non-oxidative ethanol metabolite that can be detected in several matrices (e.g. blood, urine, hair, meconium) for variable periods of time. Quantification of EtG in hair (hEtG) has established itself, over recent years, as one of the most reliable biomarkers of long-term alcohol consumption habits, with the Society of Hair Testing (SoHT) offering cut-off values for assessment of both abstinence and heavy drinking (>60 g/day). Despite its high diagnostic performance, however, issues concerning inter- and intra-laboratory variability as well as data interpretation are still being investigated and represent the ultimate barrier to widespread acceptance of hEtG in the forensic context. The aim of this review is to summarize currently available analytical methods of hEtG testing, provide a framework to understand current hEtG cut-offs and their possible upcoming changes (in particular, a lower abstinence cut-off has been proposed for the 2019 revision of the SoHT consensus), and offer a schematic but exhaustive overview of the pitfalls in result reproducibility and interpretation that may limit applications of hEtG testing in the forensic context. Ultimately, the purpose of the authors is not to undermine the reliability of hEtG as an alcohol use marker, but rather to enhance it by promoting familiarization with all aspects related to it, from ethanol pharmacokinetics and EtG incorporation into hair, to sample preparation and analytical methods, to specific cases warranting close attention and additional tests for correct interpretation of hEtG results.

  • Variability on Ethyl Glucuronide concentrations in hair depending on sample pretreatment, using a new developed GC-MS/MS method.
    Journal of Pharmaceutical and Biomedical Analysis, 2018
    Co-Authors: Claudia Vignali, Stefania Ortu, Cristiana Stramesi, Francesca Freni, Matteo Moretti, Luca Tajana, Angelo Groppi, Antonio Marco Maria Osculati, Luca Morini
    Abstract:

    Abstract Quantitative determination of Ethyl Glucuronide in keratin matrix, particularly in hair samples, provides a significant contribution to the evaluation of the extent of ethanol intake. The first-choice method to carry out this analysis is LC–MS/MS, but other techniques may be used. The aim of this work is: a) to develop and validate a GC–MS/MS method for Ethyl Glucuronide determination in hair; b) to compare GC–MS/MS and LC–MS/MS in analysis of real samples; c) to compare EtG concentration obtained after hair cutting and pulverization. About 30 mg hair samples were washed, pulverized and soaked in 1 ml deionized water. After incubation, the solution was purified through a SPE anion exchange cartridge; the eluate was dried under nitrogen stream, derivatized with PFPA and reconstituted in n-hexane. Then, the sample was injected in the GC–MS/MS system, operating in negative chemical ionization mode and in selected reaction monitoring. The two most intense transitions were used to monitor Ethyl Glucuronide and deuterated internal standard. All the validation parameters fulfilled the international acceptance criteria. LOD and LOQ were set at 2.0 and 3.0 pg/mg respectively. This method was applied to 194 hair samples collected from teetotallers and alcohol consumers and represents a suitable alternative to LC–MS/MS for the determination of EtG in hair samples, in particular when scarce quantity of hair is available. This study confirmed that pulverization of hair increases the concentration of EtG, but some variability of EtG levels remains probably due to the presence of non-homogeneous material even though pulverization.

  • Ethyl Glucuronide Elimination Kinetics in Fingernails and Comparison to Levels in Hair.
    Alcohol and alcoholism (Oxford Oxfordshire), 2017
    Co-Authors: Jan Toralf Fosen, Luca Morini, Jørg Mørland, Cristina Sempio, Nefele Giarratana, Asle Enger, Gudrun Høiseth
    Abstract:

    Aims Measurement of Ethyl Glucuronide (EtG) in nail, as a biomarker for alcohol intake, has recently been suggested as alternative to measurement in hair. The aim of this study was to compare levels of EtG in nail and hair, and to investigate the elimination kinetics of EtG in fingernails during an alcohol abstinent period. Methods Overall, 40 subjects (median estimated daily intake of ethanol (EDI) 92.5 g/day) were recruited from an alcohol rehabilitation clinic. Nail and hair samples were collected at inclusion and nail clippings were collected every 7-10th day for up to 12 weeks. Results All patients showed higher nail EtG/EDI ratios compared to hair EtG/EDI ratios (P < 0.001). The median value of the ratios between EtG in nail and EtG in hair was 5.0 (range: 1.07-56.1). There was a significant correlation between nail EtG/EDI and hair EtG/EDI (Spearman's ρ = 0.638, P < 0.001). EtG disappeared from nails after ~2 months of abstinence and the median calculated EtG half-life in nail clippings was 13.3 days (range: 5.5-29.0). There was a significant correlation between the time elapsed to last positive sample for nail EtG and nail EtG levels at time of inclusion (Spearman's ρ = 0.449, P = 0.004). Conclusion The present data indicate that EtG cut-off levels in nails should be higher compared to the established 30 pg/mg EtG cut-off in hair representing heavy drinking. EtG may disappear faster from nail than expected from nail growth physiology. Short summary Nails are an alternative matrix to hair when measuring Ethyl Glucuronide (EtG). The present study indicate that EtG cut-off levels in nails should be higher compared to the established 30 pg/mg EtG cut-off in hair representing heavy drinking, and EtG may disappear faster from nail than expected.

  • Higher levels of hair Ethyl Glucuronide in patients with decreased kidney function.
    Alcoholism: Clinical and Experimental Research, 2012
    Co-Authors: Gudrun Høiseth, Luca Morini, Rudiger Ganss, Kristin Nordal, Jørg Mørland
    Abstract:

    Background Hair levels of Ethyl Glucuronide (EtG) are often used to differentiate social drinking from heavy drinking. Patients with decreased kidney function have delayed excretion of EtG, and increased incorporation into hair could be suspected. The aim of this study was to compare hair EtG levels in patients with decreased kidney function to those seen in healthy volunteers. Methods Twelve patients with renal disease were included. The levels of EtG in hair were adjusted to estimated daily intake of ethanol (EDI) and compared to 21 previously published healthy individuals. Results The levels of hair EtG in the 12 patients ranged between < limit of detection and 134 pg/mg, and the EDI ranged between 0.1 and 12 g. The levels of EtG in hair were significantly higher in the patients compared to healthy volunteers (p = 0.009). Conclusions These preliminary results indicate that hair levels of EtG in a population of patients with decreased kidney function should be interpreted with caution.

  • Higher levels of hair Ethyl Glucuronide in patients with decreased kidney function.
    Alcoholism clinical and experimental research, 2012
    Co-Authors: Gudrun Høiseth, Luca Morini, Rudiger Ganss, Kristin Nordal, Jørg Mørland
    Abstract:

    Hair levels of Ethyl Glucuronide (EtG) are often used to differentiate social drinking from heavy drinking. Patients with decreased kidney function have delayed excretion of EtG, and increased incorporation into hair could be suspected. The aim of this study was to compare hair EtG levels in patients with decreased kidney function to those seen in healthy volunteers. Twelve patients with renal disease were included. The levels of EtG in hair were adjusted to estimated daily intake of ethanol (EDI) and compared to 21 previously published healthy individuals. The levels of hair EtG in the 12 patients ranged between < limit of detection and 134 pg/mg, and the EDI ranged between 0.1 and 12 g. The levels of EtG in hair were significantly higher in the patients compared to healthy volunteers (p = 0.009). These preliminary results indicate that hair levels of EtG in a population of patients with decreased kidney function should be interpreted with caution. Copyright © 2012 by the Research Society on Alcoholism.

Anders Helander - One of the best experts on this subject based on the ideXlab platform.

  • Solid-phase extraction procedure for Ethyl Glucuronide in urine.
    Journal of analytical toxicology, 2008
    Co-Authors: Yufang Zheng, Anders Helander
    Abstract:

    Measurement of the conjugated ethanol metabolite Ethyl Glucuronide (EtG) in urine is increasingly being used as a biomarker for recent alcohol consumption. Prior to quantification of EtG by mass spectrometric (MS) methods [liquid chromatography (LC)–MS or gas chromatography–MS], there is sometimes need for sample cleanup to remove interfering matrix constituents. A solid-phase extraction (SPE) procedure using a HyperSep SAX strong anion exchanger was developed for sample cleanup of urinary EtG prior to LC–MS analysis. The EtG content in a 50–100-µL urine sample was finally reconstituted in the same volume as the original aliquot. The cleaner SPE extracts, without sample dilution, allowed for improved quantification of urinary EtG in the low concentration range. The detection limit of the SPE procedure when combined with LC–MS analysis was < 0.1 mg/L EtG, and the assay imprecision < 5.5% (total CV) in the 0.5–5.0 mg/L concentration range. The absolute recovery of urinary EtG was ~80%, which was compensated for by using a deuterated analogue (EtG-d 5) as internal standard. The urinary EtG results with SPE followed by LC–MS were highly correlated (r 2 = 0.959) with those obtained using a sensitive and selective ultraperformance LC–tandem MS method.

  • Evaluation of a new immunoassay for urinary Ethyl Glucuronide testing
    Alcohol and alcoholism (Oxford Oxfordshire), 2007
    Co-Authors: Michael Böttcher, Olof Beck, Anders Helander
    Abstract:

    Aims: The minor ethanol metabolite Ethyl Glucuronide (EtG) is used as a sensitive and specific test for recent alcohol consumption with clinical and forensic applications. This study evaluated a new enzyme immunoassay (DRI-EtG EIA, Microgenics Corp.) for determination of the EtG concentration in urine samples. Methods: Evaluation was done using the kit calibrators (range 0-5.0 mg/L) and controls, an external quality control sample, and 400 consecutive urines from the routine samples pool. The measuring range was extended by dilution of urine samples with saline. Comparison was made with an established liquid chromatographic-mass spectrometric (LC-MS) method. Results: The intra- and inter-assay imprecision of the DRI-EtG EIA in the range 0.4-2.5 mg/L was

  • evaluation of a new immunoassay for urinary Ethyl Glucuronide testing
    Alcohol and Alcoholism, 2007
    Co-Authors: Michael Böttcher, Olof Beck, Anders Helander
    Abstract:

    Aims: The minor ethanol metabolite Ethyl Glucuronide (EtG) is used as a sensitive and specific test for recent alcohol consumption with clinical and forensic applications. This study evaluated a new enzyme immunoassay (DRI-EtG EIA, Microgenics Corp.) for determination of the EtG concentration in urine samples. Methods: Evaluation was done using the kit calibrators (range 0-5.0 mg/L) and controls, an external quality control sample, and 400 consecutive urines from the routine samples pool. The measuring range was extended by dilution of urine samples with saline. Comparison was made with an established liquid chromatographic-mass spectrometric (LC-MS) method. Results: The intra- and inter-assay imprecision of the DRI-EtG EIA in the range 0.4-2.5 mg/L was <2.2% (coefficient of variation, CV), and the limit of quantification was <0.1 mg/L. For the 400 urine samples, the EtG concentrations obtained using the DRI-EtG EIA (mean 24.2 mg/L, range 0-830) and LC-MS method (mean 22.4 mg/L, range 0-959) showed an overall good and statistically significant agreement (r 2 = 0.931 ,P < 0.0001). Conclusions: These results indicated a high level of accuracy and selectivity of the DRI-EtG EIA for quantification of urinary EtG. In the absence of a commonly accepted cut-off limit for urinary EtG, a threshold of 0.5 mg/L (2.2 µmol/L) is proposed, to obtain a high sensitivity but avoid positive results due to unintentional ethanol exposure.

  • Comparison of urinary excretion characteristics of ethanol and Ethyl Glucuronide.
    Journal of analytical toxicology, 2002
    Co-Authors: Helen Dahl, Nikolai Stephanson, Olof Beck, Anders Helander
    Abstract:

    I This study compared the urinary excretion characteristics of Ethyl Glucuronide (EtG) with that of ethanol, with focus on the effect of water-induced diuresls. Six healthy volunteers ingested an ethanol dose of 0.5 g/kg (range 25.0-41.5 g) as 5% (v/v) beer in 30 rain and the same volume of water after 3 h. Urine collections were made before starting the experiment and at timed intervals over 31.5 h. The concentration of EtG was determined by LC-MS method (LOQ = 0.1 mg/L). The urine samples collected immediately before starting drinking were all negative for ethanol and EtG, thus confirming that the participants had not recently ingested alcohol. Intake of beer resulted in a marked increase in excreted urine volume and a concomitant drop in creatinine concentration. The concentration of ethanol peaked at a mean value of 17 mmol/I, in the 1.5-h urine collection. Except for one subject, EtG was first detectable (range 0.9-5.5 rag/L) at 1 h. Intake of water at 3 h produced another increase in urine volume and a drop in creatinine. The ethanol concentration curve was not influenced by the water diuresis, whereas this caused a distinct drop in the EtG concentration. When EtG was expressed relative to the creatinine value, this ratio was seemingly not affected by the intake of water. The ethanol concentration returned to zero at 6.5 h, whereas EtG was still detectable for up to 22.5-31.5 h, albeit at low levels in the end (< 1 rag/L). Only about 0.02% of the administered dose of ethanol (on a molar basis) was recovered in the urine as EtG. The results demonstrated that EtG remains

  • Direct quantification of Ethyl Glucuronide in clinical urine samples by liquid chromatography-mass spectrometry.
    Therapeutic drug monitoring, 2002
    Co-Authors: Nikolai Stephanson, Helen Dahl, Anders Helander, Olof Beck
    Abstract:

    Ethyl Glucuronide is a minor metabolite of ethanol, and its presence in urine can be used as a laboratory test to detect recent alcohol intake, even for some time after the ethanol is no longer measurable. A simple analytical procedure was developed based on direct injection of urine diluted with a deuterated internal standard into an electrospray liquid chromatographic-mass spectrometric (LC-MS) system. A novel LC system using a porous graphite column (Hypercarb) enabled an isocratic elution with retention times of 5-6 minutes. The intra- and inter-assay coefficients of variation were 2-12%, and the measuring range was 0.1-1,500 mg/L (0.45-6,750 micromol/L). Ethyl Glucuronide was found to be stable in urine for more than 4 days at room temperature, and no artifactual formation was observed on storage of urine samples fortified with 1% ethanol. Ethyl Glucuronide was not detected in urine samples collected after abstinence from alcohol. Intake of a very low amount (7 g) of ethanol produced Ethyl Glucuronide values up to 8.4 mg/L after 4 hours and was still detectable at 6 hours. When the method was applied for routine screening of 252 clinical urine samples (range, 0-1,240 mg/L), it fulfilled the need for a simple and reliable assay to be used in the evaluation of urinary Ethyl Glucuronide as a routine test of recent alcohol intake.

Michel Yegles - One of the best experts on this subject based on the ideXlab platform.

  • Ethyl Glucuronide concentrations in hair: a controlled alcohol-dosing study in healthy volunteers
    Analytical and Bioanalytical Chemistry, 2016
    Co-Authors: Cleo Crunelle, Michel Yegles, Kristof E Maudens, Mireille De Doncker, Delphine Cappelle, Geert Dom, Peter Michielsen, Alexander L. N. Nuijs, Adrian Covaci, Hugo Neels
    Abstract:

    Ethyl Glucuronide (EtG) is a minor phase II metabolite of alcohol that accumulates in hair. It has been established as a sensitive marker to assess the retrospective consumption of alcohol over recent months using a cut-off of ≥7 pg/mg hair to assess repeated alcohol consumption. The primary aim was to assess whether amounts of alcohol consumed correlated with EtG concentrations in hair. Additionally, we investigated whether the current applied cut-off value of 7 pg/mg hair was adequate to assess the regular consumption of low-to-moderate amounts of alcohol. A prospective controlled alcohol-dosing study in 30 healthy individuals matched on age and gender. Individuals were instructed to drink no alcohol ( N  = 10), 100 g alcohol per week ( N  = 10) or 150 g alcohol per week ( N  = 10) for 12 consecutive weeks, before and after which hair was collected. Throughout the study, compliance to daily alcohol consumption was assessed by analyzing urine EtG three times weekly. Participants in the non-drinking group had median EtG concentrations of 0.5 pg/mg hair (interquartile range (IQR) 1.7 pg/mg; range 

  • Determination of Ethyl Glucuronide in hair improves evaluation of long-term alcohol abstention in liver transplant candidates
    Liver international : official journal of the International Association for the Study of the Liver, 2013
    Co-Authors: Martina Sterneck, Michel Yegles, Eik Vettorazzi, Gregor Rothkirch Von, Katharina Staufer, Karl-heinz Schulz, Niels Tobias, Christian Graeser, Lutz Fischer, Bjoern Nashan
    Abstract:

    Background & Aims Prior to listing patients for Orthotopic liver transplantation (OLT) an abstention period of 6 months is required. Ethyl Glucuronide in the hair is a new reliable marker for the assessment of alcohol consumption. Here, the diagnostic value of determining the Ethyl Glucuronide concentration in the hair of liver transplant candidates was evaluated. Methods In 63 transplant candidates with alcoholic liver cirrhosis and 25 control patients with cirrhosis of other aetiologies alcohol markers, i.e. hEtG, urine EtG, blood ethanol, methanol and carbohydrate deficient transferrin were determined in parallel to an interview with a psychologist. Results A total of 19 (30%) transplant candidates admitted alcohol consumption within the last 6 months, while 39/63 (62%) were positive for at least one alcohol marker. In 52% of the 44 candidates denying alcohol consumption, abstention was disproved by detecting at least one positive alcohol marker, in 83% of cases by a positive hEtG result. In the control patients stating abstention from alcohol all hEtG tests were negative. No impact of renal or liver function on hEtG results was detected. A specificity of 98% and a positive predictive value of 92% were calculated for testing hEtG in proximal hair segment and applying a cut-off of 30 pg/mg. Conclusions In 52% of patients denying alcohol consumption within the last 6 months, alcohol abstention was disproved, in 83% of cases by hEtG testing. Therefore, hEtG is a promising new marker for the evaluation of long-term alcohol abstention in liver transplant candidates.

  • Abstinence Monitoring of Suspected Drinking Drivers: Ethyl Glucuronide in Hair Versus CDT
    Traffic injury prevention, 2010
    Co-Authors: Bruno Liniger, Ariane Nguyen, Andrea Friedrich-koch, Michel Yegles
    Abstract:

    Objective: Ethyl Glucuronide (EtG) determinations in the hair of self-reported teetotalers were reviewed and compared with carbohydrate-deficient transferrin (CDT) blood tests (by immunochemistry and high-performance liquid chromatography [HPLC]). Methods: A retrospective study was carried out on 154 people whose fitness to drive had to be assessed because of the suspicion of relevant alcohol problems. Results: EtG was detected in 55 percent of the hair samples and abstinence thus disproved. In two thirds (67%) of these cases, alcohol consumption was even shown to be excessive (EtG values > 30 pg/mg). Of the EtG-positive subjects 54 and 82 percent had CDT values within the reference range by immunochemistry and HPLC, respectively. Thirty-nine percent of the EtG-negative subjects had increased immunochemical CDT values; in contrast, 96 percent had HPLC CDT values within the normal range. Conclusions: EtG analysis in hair is a useful tool for assessing fitness to drive in suspected drinking drivers; compare...

  • Ethyl Glucuronide determination head hair versus non head hair
    Alcohol and Alcoholism, 2008
    Co-Authors: Isabelle Kerekes, Michel Yegles, Ulfert Grimm, Robert Wennig
    Abstract:

    Introduction: In previous studies, hair analysis of Ethyl Glucuronide (EtG), a non-volatile, water-soluble, direct metabolite of ethanol, was shown to be adequate for the detection of social and chronic excessive alcohol consumption. As in some cases scalp hair is not available, the analysis of hair from alternative anatomical sites becomes of interest. Aims: In this study, hair samples from head, beard, chest, armpit, stomach, pubis, arms and legs from 32 subjects were analyzed when available, in order to compare the EtG concentrations and to study if the cut-offs used for head hair could be used for non-head hair. Methods: EtG was determined by GC/MS in negative chemical ionization mode using EtG-d5 as internal standard, after extraction by solid phase extraction using Oasis MAX columns and pentafluoropropionic anhydride (PFPA) derivatization. Results: The results showed that in the cases of negative findings in head hair (EtG < 7 pg/mg), in 7 out of 12 cases negative results could also be found in non-head hair. The five others were positive, due to a positive EtG finding in pubic hair. In 20 cases of positive EtG results for head hair, in all cases positive results could also be found in non-head hair. Conclusions: In conclusion, although preliminary results indicate a clear trend regarding the accordance between EtG results in head hair and non-head hair, interpretation of non-head hair results remains to be carefully done for pubic hair, for which often higher concentrations have been found.

  • Ethyl Glucuronide concentration in hair is not influenced by pigmentation.
    Alcohol and alcoholism (Oxford Oxfordshire), 2007
    Co-Authors: Brice M.r. Appenzeller, Marc Schuman, Michel Yegles, Robert Wennig
    Abstract:

    This work shows that the concentration of Ethyl Glucuronide (EtG) in hair, a marker for the evaluation of the alcohol consumption, is not influenced by the presence or absence of melanin. The results confirm that, unlike many other substances, the EtG determination in hair has not to take into account the hair colour for the correct interpretation of hair testing results.

Olof Beck - One of the best experts on this subject based on the ideXlab platform.

  • Sevoflurane metabolite cross-react in the Ethyl Glucuronide DRI® immunoassay.
    Drug testing and analysis, 2017
    Co-Authors: Michael Böttcher, David Kühne, Olof Beck
    Abstract:

    Ethyl Glucuronide is a direct ethanol metabolite that is used as a biomarker for recent alcohol drinking. The DRI EtG immunoassay is commonly used for screening urine for Ethyl Glucuronide. A case was encountered where EtG was positive in the screening assay but negative in the confirmation with a mass spectrometry method. This case was further investigated in order to identify cause of the false positive screening result. The sevoflurane metabolite hexafluoroisopropanol was identified in the urine with GC-MS after enzyme hydrolysis of conjugates. The hydrolysis resulted in lost reactivity in the immunoassay. We conclude, based on indirect evidence, that the sevoflurane metabolite hexafluoroisopropanol Glucuronide present in high concentration after anaesthetic treatment can cause a positive EtG screening result.

  • Evaluation of a new immunoassay for urinary Ethyl Glucuronide testing
    Alcohol and alcoholism (Oxford Oxfordshire), 2007
    Co-Authors: Michael Böttcher, Olof Beck, Anders Helander
    Abstract:

    Aims: The minor ethanol metabolite Ethyl Glucuronide (EtG) is used as a sensitive and specific test for recent alcohol consumption with clinical and forensic applications. This study evaluated a new enzyme immunoassay (DRI-EtG EIA, Microgenics Corp.) for determination of the EtG concentration in urine samples. Methods: Evaluation was done using the kit calibrators (range 0-5.0 mg/L) and controls, an external quality control sample, and 400 consecutive urines from the routine samples pool. The measuring range was extended by dilution of urine samples with saline. Comparison was made with an established liquid chromatographic-mass spectrometric (LC-MS) method. Results: The intra- and inter-assay imprecision of the DRI-EtG EIA in the range 0.4-2.5 mg/L was

  • evaluation of a new immunoassay for urinary Ethyl Glucuronide testing
    Alcohol and Alcoholism, 2007
    Co-Authors: Michael Böttcher, Olof Beck, Anders Helander
    Abstract:

    Aims: The minor ethanol metabolite Ethyl Glucuronide (EtG) is used as a sensitive and specific test for recent alcohol consumption with clinical and forensic applications. This study evaluated a new enzyme immunoassay (DRI-EtG EIA, Microgenics Corp.) for determination of the EtG concentration in urine samples. Methods: Evaluation was done using the kit calibrators (range 0-5.0 mg/L) and controls, an external quality control sample, and 400 consecutive urines from the routine samples pool. The measuring range was extended by dilution of urine samples with saline. Comparison was made with an established liquid chromatographic-mass spectrometric (LC-MS) method. Results: The intra- and inter-assay imprecision of the DRI-EtG EIA in the range 0.4-2.5 mg/L was <2.2% (coefficient of variation, CV), and the limit of quantification was <0.1 mg/L. For the 400 urine samples, the EtG concentrations obtained using the DRI-EtG EIA (mean 24.2 mg/L, range 0-830) and LC-MS method (mean 22.4 mg/L, range 0-959) showed an overall good and statistically significant agreement (r 2 = 0.931 ,P < 0.0001). Conclusions: These results indicated a high level of accuracy and selectivity of the DRI-EtG EIA for quantification of urinary EtG. In the absence of a commonly accepted cut-off limit for urinary EtG, a threshold of 0.5 mg/L (2.2 µmol/L) is proposed, to obtain a high sensitivity but avoid positive results due to unintentional ethanol exposure.

  • Comparison of urinary excretion characteristics of ethanol and Ethyl Glucuronide.
    Journal of analytical toxicology, 2002
    Co-Authors: Helen Dahl, Nikolai Stephanson, Olof Beck, Anders Helander
    Abstract:

    I This study compared the urinary excretion characteristics of Ethyl Glucuronide (EtG) with that of ethanol, with focus on the effect of water-induced diuresls. Six healthy volunteers ingested an ethanol dose of 0.5 g/kg (range 25.0-41.5 g) as 5% (v/v) beer in 30 rain and the same volume of water after 3 h. Urine collections were made before starting the experiment and at timed intervals over 31.5 h. The concentration of EtG was determined by LC-MS method (LOQ = 0.1 mg/L). The urine samples collected immediately before starting drinking were all negative for ethanol and EtG, thus confirming that the participants had not recently ingested alcohol. Intake of beer resulted in a marked increase in excreted urine volume and a concomitant drop in creatinine concentration. The concentration of ethanol peaked at a mean value of 17 mmol/I, in the 1.5-h urine collection. Except for one subject, EtG was first detectable (range 0.9-5.5 rag/L) at 1 h. Intake of water at 3 h produced another increase in urine volume and a drop in creatinine. The ethanol concentration curve was not influenced by the water diuresis, whereas this caused a distinct drop in the EtG concentration. When EtG was expressed relative to the creatinine value, this ratio was seemingly not affected by the intake of water. The ethanol concentration returned to zero at 6.5 h, whereas EtG was still detectable for up to 22.5-31.5 h, albeit at low levels in the end (< 1 rag/L). Only about 0.02% of the administered dose of ethanol (on a molar basis) was recovered in the urine as EtG. The results demonstrated that EtG remains

  • Direct quantification of Ethyl Glucuronide in clinical urine samples by liquid chromatography-mass spectrometry.
    Therapeutic drug monitoring, 2002
    Co-Authors: Nikolai Stephanson, Helen Dahl, Anders Helander, Olof Beck
    Abstract:

    Ethyl Glucuronide is a minor metabolite of ethanol, and its presence in urine can be used as a laboratory test to detect recent alcohol intake, even for some time after the ethanol is no longer measurable. A simple analytical procedure was developed based on direct injection of urine diluted with a deuterated internal standard into an electrospray liquid chromatographic-mass spectrometric (LC-MS) system. A novel LC system using a porous graphite column (Hypercarb) enabled an isocratic elution with retention times of 5-6 minutes. The intra- and inter-assay coefficients of variation were 2-12%, and the measuring range was 0.1-1,500 mg/L (0.45-6,750 micromol/L). Ethyl Glucuronide was found to be stable in urine for more than 4 days at room temperature, and no artifactual formation was observed on storage of urine samples fortified with 1% ethanol. Ethyl Glucuronide was not detected in urine samples collected after abstinence from alcohol. Intake of a very low amount (7 g) of ethanol produced Ethyl Glucuronide values up to 8.4 mg/L after 4 hours and was still detectable at 6 hours. When the method was applied for routine screening of 252 clinical urine samples (range, 0-1,240 mg/L), it fulfilled the need for a simple and reliable assay to be used in the evaluation of urinary Ethyl Glucuronide as a routine test of recent alcohol intake.

Georg Schmitt - One of the best experts on this subject based on the ideXlab platform.

  • Excretion Profiles of Ethyl Glucuronide in Human Urine after Internal Dilution
    Journal of analytical toxicology, 2002
    Co-Authors: Marion Goll, Georg Schmitt, Beate Ganßmann, R. Aderjan
    Abstract:

    Ethyl Glucuronide (EG) is a useful marker of alcohol consumption because its presence in urine can be detected up to five days. We investigated the impact of diuresis on the urinary excretion of EG, a minor ethanol metabolite. Seven healthy volunteers drank 250 mL of wine (25 g ethanol) in 15 min and, 240 min later, ingested 1 L of water within 15 min. Urine was voided before the drinking started and every 30-60 min for 400-550 min thereafter. Urinary Ethyl Glucuronide (UEG), creatinine, and ethanol were determined using liquid chromatography-tandem mass spectrometry, Jaffe's method, and the enzymatic ADH method, respectively. The maximum diuresis coincided with the lowest values of the UEG concentrations of 2 mg/L and the lowest creatinine values of 10 mg/dL 250-400 min after drinking. After drinking the wine, the urinary creatinine decreased slowly. After a short period of increasing, it decreased to minimum values caused by the water intake. After the intake of 1 L water, the diuresis increased within 60 min to its maximum. The amount of Ethyl Glucuronide excreted in urine was 10 mg (SD 5 mg) corresponding to 0.04% (SD 0.02%) of the dose administered. In successive voids during the elimination phase, the UEG and the diuresis were influenced after the subjects drank 1 L of water. Minimum UEG values of 0.5 mg/L could still be measured. Measuring UEG provides a reliable way to monitor recent drinking of alcohol. However, urinary creatinine needs to be measured additionally. Establishing a cutoff value of 25 mg/dL for urinary creatinine in diluted samples, like for the analysis of illicit drugs, is recommended. If the creatinine value is too low, the analyst has to decide about the further procedure.

  • Preliminary Immunochemical Test for the Determination of Ethyl Glucuronide in Serum and Urine: Comparison of Screening Method Results with Gas Chromatography-Mass Spectrometry
    Journal of analytical toxicology, 2002
    Co-Authors: Holger Zimmer, Georg Schmitt, Rolf Aderjan
    Abstract:

    Ethyl Glucuronide is a highly specific metabolite of ethanol that is formed by enzymatic conjugation of ethanol with glucuronic acid. Because of its suitability as a marker of excessive alcohol consumption in serum with low blood-alcohol concentration and as a consumption marker in serum and urine, especially after the breakdown of ethanol, demand exists for a simple and fast analytical procedure, which is rarely possible using mass spectrometric determination methods. For this reason, we developed an immunochemical screening procedure (ELISA) in which polyclonal antibodies are bound to the walls of microtiter plates. To test suitability, 335 authentic serum and 186 urine samples were examined using immunochemistry and gas chromatography-mass spectrometry (GC-MS). The serum (urine) samples with cutoff values of 0.31 mg/L (1.33 mg/L) yielded false-negative results in 9.5% (24.3%) and false positives in 8.4% (23.2%) of cases. Specificity was calculated at 91.6% (76.8%) and sensitivity at 90.5% (75.7%). Test efficiency was 90.8% (76.3%). The study shows that Ethyl Glucuronide and therefore alcohol consumption can be detected in immunochemical screening of serum in a similar manner as current drugs, but the method is of limited value for urine. A GC-MS confirmation continues to remain a necessity.

  • Ethyl Glucuronide in human hair.
    Alcohol and alcoholism (Oxford Oxfordshire), 2000
    Co-Authors: Gisela Skopp, Georg Schmitt, Lucia Pötsch, Peter Drönner, Rolf Aderjan, Rainer Mattern
    Abstract:

    Ethyl Glucuronide (EtG) is considered to be a promising candidate marker of alcohol consumption, but exhibits a short window of detection in blood or urine. Keratinized tissues are known to retain foreign substances and to provide a greater retrospective window of detection than body fluids. Therefore, post-mortem hair, skin swabs, and stratum corneum samples were collected from four subjects with a reported history of alcohol misuse and from seven subjects with a report of regular, socially accepted drinking behaviour, and were investigated for EtG. Additionally, certain specimens were collected from three children, who had not yet consumed any alcoholic beverages. EtG was detectable in most of the hair and stratum corneum samples as well as in perspiration stains from alcohol-consuming subjects. The results indicated that EtG might be formed locally in very small and highly variable amounts. The most important finding was that EtG cannot be expected to be generally detectable in keratinized tissues or perspiration stains from alcohol-drinking subjects, whereas a positive result is always associated with recent alcohol consumption.

  • Ethyl Glucuronide concentration in serum of human volunteers, teetotalers, and suspected drinking drivers.
    Journal of forensic sciences, 1997
    Co-Authors: Georg Schmitt, Gisela Skopp, P. Droenner, R. Aderjan
    Abstract:

    The kinetic profile of ethanol and Ethyl Glucuronide (EtG) in serum was investigated in three subject groups: 1) Healthy, moderately drinking volunteers (daily intake less than 30 g ethanol) who ingested a single dose of ethanol. In this group the maximum of serum Ethyl Glucuronide concentration (SEtGC) and of serum ethanol concentration (SEC) did not exceed 3.7 mg/L and 1.5 g/L respectively. EtG peaked 2 to 3.5 h later than ethanol. EtG was eliminated with a terminal half-life of 2 to 3 h. EtG decreased slower than ethanol--the metabolite could still be determined in serum up to 8 h after complete ethanol elimination. 2) In serum samples of teetotalers neither ethanol nor EtG could be found. 3) In 37 of 50 serum samples of drivers suspected of driving under the influence of ethanol, SEtGC was found between the limit of detection (0.1 mg/L) and 20 mg/L. If the SEC is less than 1 g/L and the SEtGC is significantly higher than 5 mg/L, we assume alcohol misuse.

  • Ethyl Glucuronide: an unusual ethanol metabolite in humans. Synthesis, analytical data, and determination in serum and urine
    Journal of analytical toxicology, 1995
    Co-Authors: Georg Schmitt, R. Aderjan, Thomas Keller
    Abstract:

    Ethyl Glucuronide (Ethyl beta-D-6-glucosiduronic acid), a minor ethanol metabolite in serum or urine, was determined by gas chromatography-mass spectrometry. Prior to this, Ethyl Glucuronide was synthesized by the reaction of acetobromo-glucosiduronic acid with ethanol. For the determination of Ethyl Glucuronide, serum samples were precipitated with acetone, and urine specimens were analyzed after evaporation to dryness. The residues were derivatized with acetic anhydride. Capillary gas chromatography was used to find a retention index value of 1920 for the triacetyl derivative. The mass spectrum of the acetylated Ethyl Glucuronide was recorded. The calibration is linear in the range investigated (0.1-150 mg/L), and the detection limit is 0.1 mg/L. In individual specimens containing between 0.1 and 4 g ethanol per liter serum, Ethyl Glucuronide could be detected at concentrations between 3 and 14 mg/L and in the corresponding urine specimens at concentrations between 3 and 130 mg/L.