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Sainte-Foy-lès-Lyon, France

Imbert L.,Martin Luther University of Halle Wittenberg | Gaulier J.-M.,Martin Luther University of Halle Wittenberg | Dulaurent S.,Martin Luther University of Halle Wittenberg | Morichon J.,Martin Luther University of Halle Wittenberg | And 3 more authors.
International Journal of Legal Medicine | Year: 2014

Ethyl glucuronide (EtG) is a direct marker of ethanol consumption, and its assay in hair is an efficient tool for chronic alcoholism diagnosis. In 2012, the Society of Hair Testing proposed a new consensus for hair concentrations interpretation, strongly advising the use of analytical methods providing a limit of quantification of less than 3 pg/mg. The present work describes the optimization and validation of a previously developed liquid chromatography-tandem mass spectrometric method in order to comply with this recommendation. The concentration range of this improved method is from 3 to 1,000 pg/mg. Some cases are then described to illustrate the usefulness of hair EtG: a forensic post-mortem case and two cases of suspension of driving licences. Finally, hair samples of some teetotallers (n = 10) have been analyzed, which allowed neither to quantitate nor to detect any trace of EtG. © 2013 Springer-Verlag Berlin Heidelberg.

Mazoyer C.,Laboratoire LAT LUMTOX | Carlier J.,Laboratoire LAT LUMTOX | Boucher A.,Center Devaluation Et Dinformation Sur La Pharmacodependance Of Lyon | Peoc'h M.,Service de Medecine Legale | And 2 more authors.
Journal of Forensic Sciences | Year: 2013

We report the case of a man who died twelve hours after ingesting powdered iboga root, commonly taken for its stimulant and hallucinogenic properties. Ibogaine and ibogamine were quantified in the powder ingested and the victim's body fluids by GC-MS/MS after liquid-liquid extraction (Toxi-tubes A®). The concentrations of ibogaine measured in the blood samples taken at the scene and in the peripheral blood, urine, and gastric fluid samples taken during the autopsy were 0.65, 1.27, 1.7, and 53.5 μg/mL, while the iboga content in the powder was 7.2%. Moreover, systematic toxicological analyses of biological samples showed the presence of diazepam and methadone in therapeutic concentrations. Death was attributed to the ingestion of a substantial quantity of iboga in the context of simultaneous methadone and diazepam consumption. © 2013 American Academy of Forensic Sciences.

Bevalot F.,Laboratoire LAT LUMTOX | Bevalot F.,University Claude Bernard Lyon 1 | Cartiser N.,University Claude Bernard Lyon 1 | Bottinelli C.,Laboratoire LAT LUMTOX | And 3 more authors.
Forensic Toxicology | Year: 2015

Forensic toxicology involves two possible levels of interpretation: qualitative (detection of xenobiotic consumption by the victim) and quantitative (assessing the implication of xenobiotics in death). Based on six drugs (meprobamate, morphine, cyamemazine, caffeine, diazepam, and citalopram) used as test substances, an animal experiment was combined with a series of autopsy cases to assess both qualitatively and quantitatively the use of bile and vitreous humor (VH) as alternative matrices to blood. The six molecules were administered to rabbits at various time points prior to euthanasia, and a human autopsy series (n > 20) was set up for each molecule. Bile, blood, and VH were analyzed using gas chromatography–tandem mass spectrometry (GC–MS/MS) according to two previously published methods. Ratios and correlations between bile/blood and VH/blood concentrations were determined. Both bile and VH demonstrated value qualitatively, allowing detection of all six molecules, possibly with longer detection windows than with blood. All six molecules showed a significant correlation between blood and VH concentrations in rabbits, whereas no such correlation was found in the autopsy series for cyamemazine or diazepam. In bile, correlations were found for meprobamate and caffeine in both rabbits and humans. Thus, bile and VH can be interpreted quantitatively for certain molecules. Combining the two experimental approaches demonstrated the impact of forensic (drug intake-to-death interval) and other parameters such as unbound fraction and molecular mass on xenobiotic distribution in these two alternative matrices. Pharmacokinetic and physicochemical parameters influencing the distribution of molecules were thus proposed, and were recommended to be taken into account when interpreting the behavior of other drugs. © 2014, Japanese Association of Forensic Toxicology and Springer Japan.

Bevalot F.,Laboratoire LAT LUMTOX | Bevalot F.,University Claude Bernard Lyon 1 | Cartiser N.,University Claude Bernard Lyon 1 | Bottinelli C.,Laboratoire LAT LUMTOX | And 4 more authors.
Forensic Toxicology | Year: 2016

Vitreous humor (VH) is a gelatinous substance contained in the posterior chamber of the eye, playing a mechanical role in the eyeball. It has been the subject of numerous studies in various forensic applications, primarily for the assessment of postmortem interval and for postmortem chemical analysis. Since most of the xenobiotics present in the bloodstream are detected in VH after crossing the selective blood-retinal barrier, VH is an alternative matrix useful for forensic toxicology. VH analysis offers particular advantages over other biological matrices: it is less prone to postmortem redistribution, is easy to collect, has relatively few interfering compounds for the analytical process, and shows sample stability over time after death. The present study is an overview of VH physiology, drug transport and elimination. Collection, storage, analytical techniques and interpretation of results from qualitative and quantitative points of view are dealt with. The distribution of xenobiotics in VH samples is thus discussed and illustrated by a table reporting the concentrations of 106 drugs from more than 300 case reports. For this purpose, a survey was conducted of publications found in the MEDLINE database from 1969 through April 30, 2015. © 2015, The Author(s).

Bevalot F.,Laboratoire LAT LUMTOX | Bevalot F.,University Claude Bernard Lyon 1 | Bottinelli C.,Laboratoire LAT LUMTOX | Cartiser N.,University Claude Bernard Lyon 1 | And 3 more authors.
Journal of Analytical Toxicology | Year: 2014

An automated solid-phase extraction (SPE) protocol followed by gas chromatography coupled with tandem mass spectrometry was developed for quantification of caffeine, cyamemazine, meprobamate, morphine and 6-monoacetylmorphine (6-MAM) in 11 biological matrices [blood, urine, bile, vitreous humor, liver, kidney, lung and skeletal muscle, brain, adipose tissue and bone marrow (BM)]. The assay was validated for linearity, within-and between-day precision and accuracy, limits of quantification, selectivity, extraction recovery (ER), sample dilution and autosampler stability on BM. For the other matrices, partial validation was performed (limits of quantification, linearity, within-day precision, accuracy, selectivity and ER). The lower limits of quantification were 12.5 ng/mL(ng/g) for 6-MAM, morphine and cyamemazine, 100 ng/mL(ng/g) for meprobamate and 50 ng/ mL(ng/g) for caffeine. Analysis of real-case samples demonstrated the performance of the assay in forensic toxicology to investigate challenging cases in which, for example, blood is not available or in which analysis in alternative matrices could be relevant. The SPE protocol was also assessed as an extraction procedure that could target other relevant analytes of interest. The extraction procedure was applied to 12 molecules of forensic interest with various physicochemical properties (alimemazine, alprazolam, amitriptyline, citalopram, cocaine, diazepam, levomepromazine, nordazepam, tramadol, venlafaxine, pentobarbital and phenobarbital). All drugs were able to be detected at therapeutic concentrations in blood and in the alternate matrices. © The Author 2014. Published by Oxford University Press. All rights reserved.

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