Synthetic cannabinoids in hair-Prevalence of use in abstinence control programs for driver's license regranting in Germany.

Although the use, structural variety, and prevalence of synthetic cannabinoids (SCs) have steadily increased on the drug market, they are rarely analyzed in abstinence control programs for driver's license regranting. The aim of this study was to determine the SC prevalence in these programs by analyzing hair samples collected between March 2020 and March 2021 from various regions in Germany, mainly Bavaria (40%). Specimens were analyzed quantitatively for drugs of abuse and qualitatively for 107 SCs. Hair samples were screened by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and to search for unknown SC analogs, positive samples were additionally screened by liquid chromatography-high resolution time of flight mass spectrometry (LC-qTOF/MS). The analysis of 5097 hair samples resulted in 181 SC detections (3.6%), showing a wide range of 44 SCs, with up to 13 different compounds found in a single sample. The most prevalent compounds were 5F-MDMB-PICA and MDMB-4en-PINACA; furthermore, 10 new substances not initially covered by LC-MS/MS analysis were detected by LC-qTOF/MS. The SC positivity rate was comparable to cocaine (5.4%) and amphetamine (2.6%). Only in 35 cases (0.7%), SC analysis was requested by the clients, highlighting the insufficient coverage of SC consumption in the studied collective. In summary, hair sample analysis proved to be a valuable tool to monitor the use of SCs. In order to keep pace with newly emerging SC analogs, an up-to-date analytical method is essential. Prospectively, SCs should be more routinely screened in hair analysis for abstinence control to avoid cannabis substitution by SCs.

Evidence for gender differences in the Amphetamine/Methamphetamine ratio in the hair of subjects undergoing Fitness-to-Drive testing.

BACKGROUND AND AIMS: Retrospective analysis of hair testing data provides insights in drugs abuse patterns and improves results interpretation. Cases from subjects undergoing driving fitness assessment (2010-2020) were examined to evidence patterns in methamphetamine (MA) abuse. MATERIALS AND METHODS: All cases with positive MA (≥0.025 ng/mg) were included (n = 585). Data available were gender, age, MA and A (amphetamine) in hair (h), hair color/treatment, length of proximal hair. Cases with Ah/MAh ≤ 0.35 (n = 469) were arbitrarily selected to remove as many combined A, MA users. ANOVA was performed to detect Ah/MAh predictors. RESULTS: No predictors affected Ah/MAh. A bimodal frequency distribution was observed. We clustered cases in two groups (1, Ah/MAh 0.025-0.070; 2, Ah/MAh 0.071-0.120) and performed logistic regression. Only gender exhibited significant difference across groups (p = 0.0080). Odds ratio for females falling into group 2 was 2.86 times higher (CI97.5 1.34-6.44). CONCLUSION: Literature data support the hypothesis that the two Ah/MAh groups represent different phenotypes of the CYP2D6-mediated MA N-demethylation. Whether gender plays a role in such difference could not be confirmed. However, these results provide further suggestion of an association of gender and pharmacogenomics with MA disposition, requiring these factors to be considered in future research.

LC-QTOF-MS Presumptive Identification of Synthetic Cannabinoids without Reference Chromatographic Retention/Mass Spectral Information. II. Evaluation of a Computational Approach for Predicting and Identifying Unknown High-Resolution Product Ion Mass Spectra.

Despite liquid chromatography-high-resolution tandem mass spectrometry (MS2) enables untargeted acquisition, data processing in toxicological screenings is almost invariably performed in targeted mode. We developed a computational approach based on open source chemometrics software that, starting from a suspected synthetic cannabinoid (SC) determined formula, searches for isomers in different new psychoactive substances web databases, predicts retention time (RT) and high-resolution MS2 spectrum, and compares them with the unknown providing a rank-ordered candidates list. R was applied on 105 SC measured data to develop and validate a multiple linear regression quantitative structure-activity relationship model predicting RT. Competitive Fragmentation Modeling for Metabolite Identification (CFM-ID) freeware was used to predict/compare spectra with Jaccard similarity index. Data-dependent acquisition was performed with an Agilent Infinity 1290 LC-6550 iFunnel Q-TOF MS with ZORBAX Eclipse-Plus C18 (100 × 2.1 mm2/1.8 µm) in water/acetonitrile/ammonium formate gradient. Ability of the combined RT/MS2 prediction to identify unknowns was evaluated on SC standards (with leave-one-out from the RT model) and on unexpected SC encountered in real cases. RT prediction reduced the number of isomers retrieved from a group of new psychoactive substances web databases to one-third (2,792 ± 3,358→845 ± 983) and differentiated between SC isomers when spectra were not selective (4F-MDMB-BUTINACA, 4F-MDMB-BUTINACA 2'-indazole isomer) or unavailable (4CN-Cumyl-B7AICA, 4CN-Cumyl-BUTINACA). When comparing 30/40 eV measured spectra of 99 SC against RT-selected, CFM-ID predicted spectra of isomers, the right candidate ranked 1st on median and 4th on average; 54% and 88% of times the right match ranked 1st or within the first 5 matches, respectively. To our knowledge, this is the first case of extensive chemometrics application to toxicological screening. In most cases, presumptive identification (being based on computation, it requires further information for confirmation) of unexpected SC was achieved without reference measured information. This method is currently the closest possible to true unbiased/untargeted screening. The bottleneck of the method is the processing time required to predict mass spectra (ca. 30-35 s/compound using a 64-bit 2.50-GHz Intel® Core™ i5-7200U CPU). However, strategies can be implemented to reduce prediction processing time.

LC-QTOF-MS Presumptive Identification of Synthetic Cannabinoids without Reference Chromatographic Retention/Mass Spectral Information. I. Reversed-Phase Retention Time QSPR Prediction as an Aid to Identification of New/Unknown Compounds.

The application of Quantitative Structure-Property Relationship (QSPR) modeling to the prediction of reversed-phase liquid chromatography retention behavior of synthetic cannabinoids (SC), and its use in aiding the untargeted identification of unknown SC are described in this paper. 1D, 2D molecular descriptors and fingerprints of 105 SC were calculated with PaDEL-Descriptor, selected with Boruta algorithm in R environment, and used to build-up a multiple linear regression model able to predict retention times, relative to JWH-018 N-pentanoic acid-d5 as internal standard, under the following conditions: Agilent ZORBAX Eclipse Plus C18 (100 mm × 2.1 mm I.D., 1.8 µm) column with Phenomenex SecurityGuard Ultra cartridge (C18, 10 mm × 2.1 mm I.D., < 2 µm) kept at 50°C; gradient elution with 5-mM ammonium formate buffer (pH 4 with formic acid) and acetonitrile with 0.01% formic acid, flow rate 0.5 mL/min. The model was validated by repeated k-fold cross-validation using two-thirds of the compounds as training set and one-third as test set (Q2 0.8593; root mean squared error, 0.087, ca. 0.56 min; mean absolute error, 0.060) and by predicting relative Retention Times (rRT) of 5 SC left completely out of the modeling study. Application of the model in routine work showed its capacity to discriminate isomers, to identify unexpected SC in combination with mass spectral information, and to reduce the length of the list of candidate isomers to ca. one-third, thus reducing significantly the time required for predicting high-resolution product ion spectra to be compared to the unknown using a computational Mass Spectrometry (MS) search/identification approach.

Higher Creatinine Concentrations in Ethyl Glucuronide-Positive Urine Specimens Collected from Subjects in a Controlled Alcohol Abstinence Program: Is Serum Creatinine a Good Marker of Renal Function in Drinkers?

AIMS: The aim of this study was to examine urine creatinine concentrations in drivers submitted to controlled alcohol abstinence programs. METHODS: Urine samples (n = 32,210) were screened for ethyl glucuronide (EtG) by immunoassay during a 2-year period. Non-negatives underwent EtG and ethyl sulfate (EtS) confirmation by coupled-column Liquid Chromatography-Tandem Mass Spectrometry. Urine samples were tested for dilution by the analysis of creatinine content with <0.2 g/l indicating a dilute specimen. RESULTS: The mean urine creatinine was significantly higher in EtG positives compared to negatives (1.47 ± 0.98 vs. 1.17 ± 0.79 g/l). The difference between positives and negatives was consistent within genders and age groups (<45; ≥45). The higher urinary creatinine in EtG positives is explained by a late antidiuretic effect of alcohol. CONCLUSION: Attempts to dilute urine specimens by drinking water or other liquids before voiding are less effective for EtG/EtS compared with illicit drugs excreted in urine. If the temporary decrease in serum creatinine as a consequence of the late antidiuretic effect of alcohol is confirmed by controlled studies, serum creatinine as an indicator of kidney function should be reconsidered in drinkers.

Identification of phase I and II metabolites of the new designer drug α-pyrrolidinohexiophenone (α-PHP) in human urine by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS).

Pyrrolidinophenones represent one emerging class of newly encountered drugs of abuse, also known as 'new psychoactive substances', with stimulating psychoactive effects. In this work, we report on the detection of the new designer drug α-pyrrolidinohexiophenone (α-PHP) and its phase I and II metabolites in a human urine sample of a drug abuser. Determination and structural elucidation of these metabolites have been achieved by liquid chromatography electrospray ionisation quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). By tentative identification, the exact and approximate structures of 19 phase I metabolites and nine phase II glucuronides were elucidated. Major metabolic pathways revealed the reduction of the ß-keto moieties to their corresponding alcohols, didesalkylation of the pyrrolidine ring, hydroxylation and oxidation of the aliphatic side chain leading to n-hydroxy, aldehyde and carboxylate metabolites, and oxidation of the pyrrolidine ring to its lactam followed by ring cleavage and additional hydroxylation, reduction and oxidation steps and combinations thereof. The most abundant phase II metabolites were glucuronidated ß-keto-reduced alcohols. Besides the great number of metabolites detected in this sample, α-PHP is still one of the most abundant ions together with its ß-keto-reduced alcoholic dihydro metabolite. Monitoring of these metabolites in clinical and forensic toxicology may unambiguously prove the abuse of the new designer drug α-PHP.

Uptake from water, internal distribution and bioaccumulation of selenium in Scenedesmus obliquus, Unio mancus and Rattus norvegicus: part B.

(75)Se-selenite transfer was investigated in a phytoplankton-mussel-rat food chain model consisting of Scenedesmus obliquus (Turpin) Kützing, Unio mancus Lamark and Rattus norvegicus Berkenhout. (75)Se-metabolized forms were investigated in order to identify potential critical steps in the food chain, as well as its relative bioavailability looking also at intracellular, cellular and organ partitioning. Tissue and intracellular distribution of (75)Se in mussels fed with (75)Se-S. obliquus was different compared to those exposed only to inorganic (75)Se-selenite. The intracellular distribution of (75)Se in the hepatopancreas and mantle of mussels fed (75)Se-microalgae was similar to hepatic and renal distributions in rats, suggesting that their stomach dissociated larger (75)Se-containing molecules. The (75)Se partitioned from water (culture medium) to microalgae showing a bioconcentration factor of 435. The bottleneck in the trophic transfer of (75)Se occurred between S. obliquus-U. mancus. From microalgae to mussels and subsequently to rats no bioaccumulation was verified.

Uptake from water, internal distribution and bioaccumulation of selenium in Scenedesmus obliquus, Unio mancus and Rattus norvegicus: part A.

The (75)Se internal bioavailability was investigated in microalgae, mussels and rats as biological experimental models. The (75)Se accumulation from freshwater to microalgae [Scenedesmus obliquus (Turpin) Kützing], from freshwater to mussels (Unio mancus Lamark) and, finally, per os to rats (Rattus norvegicus Berkenhout) was followed using (75)Se-labelled selenite looking at (75)Se uptake, retention, intracellular distribution and binding with cellular biocomplexes. After exposure to 10, 50 and 500 µg Se L(-1), the microalgae showed an inhibitory effect on population growth only at the highest concentration. Mussels exposed to 105 µg Se L(-1) showed an accumulation of the element with time in all tissues. Intracellularly, Se was present in all subcellular fractions, especially in the cytosol. Rats were treated via oral administration with 5 µg Se rat(-1). After 24 h, liver and kidney showed the highest Se concentration.

Determination of cocaine and metabolites in hair by column-switching LC-MS-MS analysis.

A method for rapid, selective, and robust determination of cocaine (CO) and metabolites in 5-mg hair samples was developed and fully validated using a column-switching liquid chromatography-tandem mass spectrometry system (LC-MS-MS). Hair samples were decontaminated, segmented, incubated overnight in diluted HCl, and centrifuged, and the diluted (1:10 with distilled water) extracts were analyzed in positive ionization mode monitoring two reactions per analyte. Quantifier transitions were: m/z 304.2→182.2 for CO, m/z 290.1→168.1 for benzoylecgonine (BE), and m/z 318.2→196.2 for cocaethylene (CE). The lower limit of quantification (LLOQ) was set at 0.05 ng/mg for CO and CE, and 0.012 ng/mg for BE. Imprecision and inaccuracy at LLOQ were lower than 20 % for all analytes. Linearity ranged between 0.05 and 50.0 ng/mg for CO and CE and 0.012 and 12.50 ng/mg for BE. Selectivity, matrix effect, process efficiency, recovery, carryover, cross talk, and autosampler stability were also evaluated during validation. Eighteen real hair samples and five samples from a commercial proficiency testing program were comparatively examined with the proposed multidimensional chromatography coupled with tandem mass spectrometry procedure and our reference gas chromatography coupled to mass spectrometry (GC-MS) method. Compared with our reference GC-MS method, column-switching technique and the high sensitivity of the tandem mass spectrometry detection system allowed to significantly reduce sample amount (×10) with increased sensitivity (×2) and sample throughput (×4), to simplify sample preparation, and to avoid that interfering compounds and ions impaired the ionization and detection of the analytes and deteriorate the performance of the ion source.

Evaluation of buprenorphine LUCIO immunoassay versus GC-MS using urines from a workplace drug testing program.

The buprenorphine (BUP) LUCIO Nal Von Minden screening assay was evaluated. Urine samples from subjects enrolled in a workplace drug testing program were screened according to the manufacturer's instruction using a Roche COBAS Integra 800 analyser. For gas chromatography-mass spectrometry (GC-MS) confirmatory analysis, samples were submitted to enzymatic hydrolysis with ß-glucuronidase and mixed-mode solid-phase extraction. Imprecision (coefficient of variation) for 3.0, 7.0, and 13.0 ng/mL calibrators varied within 2.8-8.7 intra-day (n = 20) and 7.7-8.6 inter-day (n = 19). Inaccuracy (bias) was between -5.6-30.5 intra-day and -13.2-4.2 inter-day. At the 5 ng/mL cut-off, the immunoassay showed 100% sensitivity and 88% specificity, with an overall agreement of 94% between immunoassay and GC-MS. Raising the cut-off to 10 ng/mL provided an identical overall agreement between immunoassay and GC-MS (94%), despite the decrease in sensitivity (90%) and the increase in specificity (100%). According to these results, the BUP LUCIO Nal Von Minden screening assay provides adequate sensitivity and specificity for BUP screening in urine samples using a cut-off concentration of 5 ng/mL.

Incorporation of methamphetamine and amphetamine in human hair following controlled oral methamphetamine administration.

BACKGROUND: Although hair testing is well established for the assessment of past drug exposure, uncertainties persist about mechanisms of drug incorporation into hair and interpretation of results. The aim of this study was to administer methamphetamine (MAMP) under controlled conditions as a model drug to investigate drug incorporation into human hair. MATERIAL AND METHODS: Seven volunteers with a history of stimulant use received 4×10 mg (low) doses of sustained release S-(+)-MAMP HCl within 1 week, with weekly head hair samples collected by shaving. 3 weeks later, 4 of them received 4×20 mg (high) doses. After extensive isopropanol/phosphate buffer washing of the hair, MAMP and its metabolite amphetamine (AMP) concentrations were determined in all weekly hair samples by LC-MS-MS in selected reaction monitoring mode with the undeca- and deca-deuterated drugs, respectively, as internal standards (LLOQ, 0.005 ng mg(-1)). RESULTS: MAMP T(max) occurred from 1 to 2 weeks after both doses, with C(max) ranging from 0.6 to 3.5 ng mg(-1) after the low and 1.2 to 5.3 ng mg(-1) after the high MAMP doses. AMP C(max) in hair was 0.1-0.3 ng mg(-1) and 0.2-0.5 ng mg(-1), respectively, for low and high doses. Highly dose-related concentrations within subjects, but large variability between subjects were observed. MAMP concentrations were above the 0.2 ng mg(-1) cut-off for at least 2 weeks following administration of both low and high doses. The overall AMP/MAMP ratio ranged from 0.07 to 0.37 with a mean value of 0.15 ± 0.07, and a median of 0.13. The percentage of MAMP and AMP removed with the washing procedure decreased with time after administration. A strong correlation was found between area under the curve of MAMP (r(2)=0.90, p=0.00) and AMP (r(2)=0.94, p=0.00) concentrations calculated for the 3-week period following administration and the total melanin concentration in hair. Significant correlations were observed also between C(max) and melanin. CONCLUSIONS: This study demonstrated that despite large inter-individual differences, the incorporation of MAMP and AMP into hair is dose-related with much of the observed scatter of MAMP and AMP concentrations explained by melanin concentration in hair.

Rapid and robust confirmation and quantification of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine by column switching LC-MS-MS analysis.

A method for the rapid and robust confirmation of 11-nor-∆9-tetrahydrocannabinol-9-carboxylic acid (THCA) in urine involving basic hydrolysis with NaOH and direct injection of the hydrolysate in a column-switching LC-MS-MS system was developed and validated. THCA-d3 was used as internal standard. Detection was performed in negative-ion mode by monitoring the transitions from the [M-CO(2) ]- ion m/z 299.2→245.2 and and m/z 299.2→191.1 that were found to provide a better signal-to-noise ratio than the transition from the pseudomolecular ion at m/z 343. The high sensitivity of detection enabled the injection of a small volume (10 µl) of the NaOH hydrolysate which, together with the applied column switching system, proved to confer ruggedness to the method and to avoid the deterioration of the instrumental apparatus despite the large amount of inorganic ions in the hydrolysate. The LLOQ was established at 5 ng/ml, and the LLOD was calculated as 0.2 ng/ml (S/N =3). The method was submitted to thorough validation including evaluation of the calibration range (5-500 ng/ml), accuracy and precision, matrix effects, overall process efficiency, autosampler stability, carryover and cross-talk, and 10-times reduction of sample volume (0.1 ml). Proof of applicability was obtained by direct comparison with the reference GC-MS method in use in the lab (the R(2) between the two methods was 0.9951).

Prevalence of drug abuse among workers: strengths and pitfalls of the recent Italian Workplace Drug Testing (WDT) legislation.

BACKGROUND: In 2008 a Workplace Drug Testing (WDT) law became effective in Italy for workers involved in public/private transportation, oil/gas companies, and explosives/fireworks industry with the aim to ensure public safety for the community. AIMS: To examine and elaborate WDT data collected on a large group of workers (over 43,500) during March 2009-February 2010 in order to highlight pros and cons and to draw suggestions for policies in the field. SETTING: Northern Italy. METHODS: After ≤ 24 h notification, workers provided a urine sample screened for opiates, methadone, buprenorphine, cocaine, amphetamines, ecstasy, and cannabinoids (THC) by immunoassay. Positives were confirmed by GC-MS. RESULTS: The positive rate was 2.0%, THC being most frequent drug (1.3%; cocaine, 0.4%; opioids, 0.3%). 6.9% of the positive workers tested positive for ≥ 2 classes (most often THC+cocaine). Gender ratio and mean age were significantly lower in positives (F/M=0.007; 35.5 ± 8.3 years) than negatives (0.016 and 40.7 ± 9.5, respectively). No decline in rates of positives and an increase of diluted samples over time were observed. The highest rates of positives were detected when sampling was performed just before/after week-end and during morning hours. Possible correlation between job type and drugs used were observed (e.g. more cocaine positives among road vehicle-drivers than among lift truck-drivers). Declared use of medicine/illicit drugs during the preceding week showed that illicit drug use was likely not always detected in urine and that almost 4% workers declared use of medicine drugs possibly affecting performance. CONCLUSIONS: This survey enabled to evidence relevant pitfalls of the law and to define strategies to improve the outcomes of WDT policies.

[Assessment of fitness to drive in correlation with narcotic and psychotropic drug use. Epidemiologic study in Verona]. / La valutazione dell'idoneità alla guida in relazione all'uso di sostanze stupefacenti e psicotrope. Studio epidemiologico della casistica veronese.

Driving under the influence of drugs is a serious problem for road traffic safety. According to the Italian Road Traffic Code, the driving licence must not be issued to anyone who abuses, is addicted to, or suffers for dependence to illicit or psychotropic drugs. The diagnosis of such clinical conditions is performed by Provincial Medical Commissions of the Public Health Service also on the basis of drugs of abuse testing results on urine and/or hair samples. This study aimed at examining test results obtained by the Forensic Toxicology laboratory of the Department of Public Health & Community Medicine, University of Verona, upon request of the local Medical Commission, over the period 2003-2008 with the purposes of (i) defining trends in drug abuse in the examined population (ii) identifying specific risk factors for testing positive and for relapse, (iii) selecting the most effective and efficient analytical strategy to detect illicit drugs use. During the study period, cocaine was the most frequently detected illicit drug. The comparison of results from urine and hair testing confirmed the complementary features of these two biological substrates and the importance to have both data in order to increase the sensitivity in detecting illicit drug use. Moreover, this study showed that testing for driving fitness is an effective deterrent to illicit drug use, as only about one quarter of subjects testing positive at the first testing are still positive at the second testing.

Screening for pharmaco-toxicologically relevant compounds in biosamples using high-resolution mass spectrometry: a 'metabolomic' approach to the discrimination between isomers.

High-resolution mass spectrometry (HRMS) enables the identification of a chemical formula of small molecules through the accurate measurement of mass and isotopic pattern. However, the identification of an unknown compound starting from the chemical formula requires additional tools: (1) a database associating chemical formulas to compound names and (2) a way to discriminate between isomers. The aim of this present study is to evaluate the ability of a novel 'metabolomic' approach to reduce the list of candidates with identical chemical formula. Urine/blood/hair samples collected from real positive cases were submitted to a screening procedure using ESI-MS-TOF (positive-ion mode) combined with either capillary electrophoresis or reversed phase liquid chromatography (LC). Detected peaks were searched against a Pharmaco/Toxicologically Relevant Compounds database (ca 50,500 compounds and phase I and phase II metabolites) consisting of a subset of PubChem compounds and a list of candidates was retrieved. Then, starting from the mass of unknown, mass shifts corresponding to pre-defined biotransformations (e.g. demethylation, glucuronidation, etc.) were calculated and corresponding mass chromatograms were extracted from the total ion current (TIC) in order to search for metabolite peaks. For each candidate, the number of different functional groups in the molecule was automatically calculated using E-Dragon software (Talete srl, Milan, Italy). Then, the presence of metabolites in the TIC was matched with functional groups data in order to exclude candidates with structures not compatible with observed biotransformations (e.g. loss of methyl from a structure not bearing methyls). The procedure was tested on 108 pharmaco-toxicologically relevant compounds (PTRC) and their phase I metabolites were detected in real positive samples. The mean list length (MLL) of candidates retrieved from the database was 7.01 +/- 4.77 (median, 7; range, 1-28) before the application of the 'metabolomic' approach, and after the application it was reduced to 4.08 +/- 3.11 (median 3, range 1-17). HRMS allows a much broader screening for PTRC than other screening approaches (e.g. library search on mass spectra databases). The 'metabolomic' approach enables the reduction of the list of candidate isomers.

Effect of bleaching on ethyl glucuronide in hair: an in vitro experiment.

INTRODUCTION: Ethyl glucuronide in hair (HEtG) has recently gained great attention, because of its high sensitivity and specificity in the diagnosis of chronic alcohol abuse. Due to its high polarity hydrophilicity, a strong hair treatment followed by a shampooing may lead to removal/degradation of this molecule from hair matrix. AIM: To set up an in vitro study in order to evaluate the ability of bleaching of modifying HEtG test results. METHODS: Thirty hair samples from teetotalers (n=5), social drinkers (n=4) and heavy drinkers (n=21), after an informed written consent, were collected and divided longitudinally into four aliquots. The first aliquot was kept untreated and was processed following the method routinely used in our lab for the determination of HEtG (double washing with methanol/dichloromethane, overnight incubation in water, and LC-MS/MS analysis, LLOQ: 3pg/mg). To the other three aliquots a commercially available bleaching solution was applied, according to the manufacturer's instructions. One out of the three aliquots was submitted to the analysis by following the same procedure used for the untreated sample. The other two were submitted to a purification step before LC-MS/MS analysis, by using two different SPE cartridges (aminopropyl and dimethyl butylamine). RESULTS: HEtG levels in the untreated samples from social drinkers and heavy drinkers ranged from 7.7 to 149.0pg/mg. All the samples from teetotalers tested negative. The treated samples processed without any SPE extraction and with aminopropyl cartridges showed a relevant ion suppression for both EtG and D(5)-EtG (IS) signals. Samples treated with the bleaching solution and extracted with dimethyl butylamine cartridge allowed to sensitively reduce ion suppression (less than 35%) and to verify that EtG, after a strong treatment like bleaching, completely disappears. CONCLUSIONS: This in vitro study showed that HEtG disappears from hair matrix after a strong hair treatment. It is not clear whether the mechanism involved is chemical degradation or physical removal from the damaged keratinic matrix. However, owing to the highly hydrophilic character of the compound, the second mechanism seems more likely to occur. Finally, bleaching solutions could lead to a heavy ion suppression of this metabolite that may be avoided by using an SPE purification before instrumental analysis.

Serum/whole blood concentration ratio for ethylglucuronide and ethyl sulfate.

Serum/blood (S/B) concentration ratios for ethyl glucuronide (EtG) and ethyl sulfate (EtS) are missing from the literature, and the aim of this study was to determine these ratios in samples from patients at admission to an alcohol rehabilitation clinic. Two blood samples were collected simultaneously, and EtG and EtS were analyzed in whole blood and serum, respectively, using a liquid chromatography-mass spectrometry method. Separate calibration standards were prepared in both whole blood and serum for the calculation of whole blood and serum concentrations, respectively. Thirteen pairs of serum and whole blood were analyzed. The median S/B value for EtG was 1.69, and the range was 1.33-1.90. For EtS, the median S/B ratio was 1.30, and the range was 1.08-1.47. The S/B ratio was significantly lower for EtS than for EtG (p < 0.001). The higher concentrations of EtG and EtS in serum than in whole blood have to be considered when whole blood results obtained from forensic toxicology are compared to serum or plasma results from clinical laboratories.

Comparison of ethyl glucuronide in hair with carbohydrate-deficient transferrin in serum as markers of chronic high levels of alcohol consumption.

This study was designed with the aim to compare sensitivity and specificity of ethyl glucuronide in hair (HEtG) and carbohydrate-deficient transferrin (CDT) in serum as markers of heavy drinking. Eighty-six volunteers, including teetotalers, social, and heavy drinkers, were interviewed to evaluate their ethanol daily intake (EDI) during the last 2-week and 3-month periods. HEtG determination was performed by a fully validated LC-MS-MS procedure and ranged from

Blood kinetics of ethyl glucuronide and ethyl sulphate in heavy drinkers during alcohol detoxification.

Studies of ethyl glucuronide (EtG) blood kinetics have so far been performed on healthy volunteers with ingestion of low to moderate doses of ethanol. These data are not necessarily transferable to heavy drinkers where the consumed doses of ethanol are much higher. The aim of this study was to investigate the pharmacokinetics of EtG and ethyl sulphate (EtS) in blood in heavy drinkers after termination of alcohol ingestion. Sixteen patients from an alcohol withdrawal clinic were included directly after admission. Time of end of drinking, estimated daily intake of ethanol (EDI) and medical history were recorded. Three to five blood samples over 20-43 h were collected from each patient subsequent to admission. The median EDI was 172 g (range 60-564). The first sample was collected median 2.5 h after end of drinking (range 0.5-23.5). Two patients had levels of EtG and EtS below LOQ in all samples, the first collected 19.25 and 23.5 h after cessation of drinking, respectively. Of the remaining 14 patients, one subject, suffering from both renal and hepatic disease, showed concentrations of EtG and EtS substantially higher than the rest of the material. This patient's initial value of EtG was 17.9 mg/L and of EtS 5.9 mg/L, with terminal elimination half lives of 11.9 h for EtG and 12.5 h for EtS. Among the remaining 13 patients, the initial median values were 0.7 g/L (range 0-3.7) for ethanol, 1.7 mg/L (range 0.1-5.9) for EtG and 0.9 mg/L (range 0.1-1.9) for EtS. Elimination occurred with a median half-life of 3.3 h for EtG (range 2.6-4.3) and 3.6 h for EtS (range 2.7-5.4). In conclusion, elimination of EtG in heavy drinkers did not significantly differ from healthy volunteers, and EtS appeared to have similar elimination rate. In the present work, there was one exception to this, and we propose that this could be explained by the patient's renal disease, which would delay excretion of these conjugated metabolites.

Ethyl glucuronide in hair. A sensitive and specific marker of chronic heavy drinking.

AIMS: This study aims to define a cut-off concentration for ethyl glucuronide in hair to determine if there was a history of heavy drinking. SETTINGS: Pavia, Italy. PARTICIPANTS: We analysed hair samples from 98 volunteers among teetotallers, social drinkers and heavy drinkers, whose ethanol daily intake (EDI) was estimated by means of a written questionnaire. MEASUREMENTS: Ethyl glucuronide hair concentration (HEtG) was measured by liquid chromatography-tandem mass spectrometry (lower limit of quantification: 3 pg/mg) using a fully validated method. FINDINGS: The HEtG level providing the best compromise between sensitivity (0.92) and specificity (0.96) at detecting an EDI of 60 g or higher during the last 3 months was 27 pg/mg. None of the factors examined among those known to affect ethanol metabolism and/or the diagnostic power of other markers of ethanol use or hair analyses, including age, gender, body mass index, tobacco smoke, prevalent beverage, hair colour, cosmetic treatments and hygienic habits was found to influence marker performance significantly. However, the slight differences in HEtG performance observed for some factors (e.g. body mass index, smoke and hair treatments) require further studies on larger groups of individuals in order to assess their influence more precisely. CONCLUSIONS: Our results confirm further that HEtG is a sensitive and specific marker of chronic heavy drinking.