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Cannabis is the most consumed drug of abuse, making it the primary target for identification and quantification in human whole blood regarding forensic and clinical toxicology analyses. Among biological matrices, blood is the reference for toxicological interpretation. A highly sensitive and selective liquid chromatography (LC) hyphenated with high-resolution mass spectrometry (HRMS) was developed for the quantification of Δ9-tetrahydrocannabinol (THC), 11-hydroxytetrahydrocannabinol (THC-OH), 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH) and cannabidiol (CBD). Those cannabinoids were extracted from 1 mL of whole blood by a simple liquid–liquid extraction (LLE) in acidic conditions. HRMS was performed on an Orbitrap-based instrument using its trapping capabilities and increased selectivity for parallel reaction monitoring (PRM) quantification in positive polarity with a negative polarity switching for THC-OH and THC-COOH. Although selected reaction monitoring (SRM) and PRM-targeted methods have similar performance in terms of linearity, dynamic range, precision and repeatability, Orbitrap-based PRM provides a higher specificity due to the use of high-resolution mode separating background ions from the targeted molecules. The method was fully validated according to guidelines set forth by the “Société Française des Sciences et des Techniques Pharmaceutiques” (SFSTP). Trueness was measured below 107% for all tested concentrations. Repeatability and intermediate precision were found to be lower than 12% while the assay was found to be linear in the concentration range of 0.4–20 ng/mL for THC, THC-OH and CBD and of 2–100 ng/mL for THC-COOH. Recovery (RE) and matrix effect (ME) ranged from 70.6 to 102.5% and from −40 to 6.6%, respectively. The validated method provides an efficient procedure for the simultaneous and rapid quantification of cannabinoids in PRM mode providing an alternative over classical SRM.

In the realm of forensic pathology, ethanol is one of the most frequently encountered xenobiotics. The determination of ethanol concentration in blood after death is of great interest in forensic settings. It is important to be able to determine the level of intoxication of the deceased at the time of death, which is directly correlated to the ability to act prior to death, especially when a suicide is suspected. This estimation is not always easy to establish owing to various artifacts that are important to know for a proper ethanol blood level interpretation, among them postmortem (PM) diffusion. We describe here a case of unusual ethanol distribution in body compartments and discuss the importance of PM diffusion and redistribution while performing complementary toxicological analysis, especially when the blood and urine samples seemed to be inconsistent after the first results.

The wastewater contamination of a Swiss university hospital by active pharmaceutical ingredient (API) residues was evaluated with a three months monitoring campaign at the outlet of the main building. Flow-proportional samples were collected with an automatic refrigerated sampler and analyzed for 15 API, including antibiotics, analgesics, antiepileptic and anti-inflammatory drugs, by using a validated LC-MS/MS method. The metals Gd and Pt were also analyzed using ICP-MS. Measured concentrations were compared to the predicted ones calculated after the drug average consumption data obtained from the hospital pharmacy. The hospital contribution to the total urban load was calculated according to the consumption data obtained from city pharmacies. Lastly, the environmental hazard and risk quotients (RQ) related to the hospital fraction and the total urban consumption were calculated. Median concentrations of the 15 selected compounds were ranging from 0.04 to 675 μg/L, with a mean detection frequency of 84%. The ratio between predicted and measured environmental concentrations (PEC/MEC) has shown a good accuracy for 5 out of 15 compounds, revealing over- and under-estimations of the PEC model. Mean daily loads were ranging between 0.01 and 14.2g/d, with the exception of paracetamol (109.7 g/d). The hospital contribution to the total urban loads varied from 2.1 to 100% according to the compound. While taking into account dilution and removal efficiencies in wastewater treatment plant, only the hospital fraction of the antibiotics ciprofloxacin and sulfamethoxazole showed, respectively, a high (RQ>1) and moderate (RQ>0.1) risk for the aquatic ecosystems. Nevertheless, when considering the total urban consumption, 7 compounds showed potential deleterious effects on aquatic organisms (RQ>1): gabapentin, sulfamethoxazole, ciprofloxacin, piperacillin, ibuprofen, diclofenac and mefenamic acid. In order to reduce inputs of API residues originating from hospitals various solutions can be envisioned. With results of the present study, hospital managers can start handling this important issue.

Objectif La presence d’ethanol apres un deces est souvent observee lors des analyses toxicologiques, et sa recherche revet une certaine importance pour evaluer le degre d’intoxication du defunt peu avant le deces et sa capacite d’agir. En outre, le rapport des concentrations entre les differentes matrices biologiques permet generalement de pouvoir determiner si l’ethanol a ete consomme avant le deces ou s’il provient d’une formation post mortem. Pour une consommation d’ethanol avant le deces, cela permet egalement de determiner dans quelle phase toxicocinetique le deces est survenu. Nous rapportons le cas d’un deces survenu par pendaison complete presentant une distribution atypique de l’ethanol dans les echantillons post mortem. Methode Le corps d’un homme de 49 ans est retrouve pendu sur son lieu de travail. L’autopsie, realisee 24 heures plus tard, a confirme l’hypothese d’un deces survenu suite a une asphyxie mecanique par pendaison complete, et des analyses toxicologiques sont demandees dans le but d’evaluer l’etat de la personne au moment du deces. Une forte odeur aromatique de la cavite abdominale a ete signalee lors de la dissection et l’estomac presentait une paroi de consistance ferme, de coloration brunâtre, comme « fixee » dans un liquide de conservation. Des analyses toxicologiques ont ete effectuees sur l’urine, a l’aide d’une batterie de tests de depistage, et d’un screening par CPG-SM apres hydrolyse, extraction basique et sylilation. Dans le sang, un screening general a ete effectue par CPL-SMHR. Le dosage de l’ethanol et des substances volatiles a ete effectue par HS-CPG-DIF. Le dosage de l’ethylglucuronide, de l’ethylsulfate et du phosphatidylethanol a ete effectue par CPL-SM. Resultats Mis a part la presence d’ethanol, de cafeine, de metabolites de la cafeine, de nicotine, et de metabolites de la nicotine, les analyses n’ont pas mis en evidence la presence de substance susceptibles de diminuer la capacite de decision ou d’action. La concentration de l’ethanol dans les cinq echantillons de sang femoral (veine iliaque) variaient de 1,53 a 2,04 g/kg, alors que dans l’urine et l’humeur vitree, la concentration d’ethanol etaient inferieure a 0,10 g/kg. Dans les autres echantillons, les concentrations d’ethanol etaient les suivantes : sang cardiaque (1,73 g/kg), serum femoral (2,61 g/kg), muscle squelettique (psoas) (5,00 g/kg), muscle cardiaque (1,12 g/kg), liquide pericardique (6,24 g/kg), foie (0,26 g/kg), bile (54 g/kg), cortex cerebral (0,14 g/kg), liquide cephalorachidien (0,21 g/kg), et dans le contenu gastrique (168 g/kg, ou environ 17 %, ou environ 67 g d’ethanol pur pour 400 g de contenu gastrique). La presence d’ethylglucuronide dans les echantillons biologiques analyses, en particulier dans les cheveux (24 pg/mg sur un segment de 5 cm), ainsi que d’ethylsulfate et de phosphatidylethanol (500 ng/ml dans le sang femoral) a ete mise en evidence. Dans le contenu gastrique, du 1-propanol (environ 130 mg/l) et de l’isobutanol (environ 71 mg/l) ont ete mis en evidence. Conclusion La distribution atypique de l’ethanol dans les echantillons biologiques parle en faveur d’une prise d’une dose massive d’ethanol dans les minutes avant le deces, ainsi que d’une diffusion post mortem importante de l’ethanol depuis le contenu gastrique. Des lors la concentration d’ethanol mesuree dans le sang femoral doit etre interpretee avec precaution, car elle ne correspond certainement pas a celle qui aurait pu etre relevee au moment du deces, qui devait etre nettement plus faible, tres vraisemblablement de l’ordre de quelques dixiemes de g/kg. Ces resultats soulignent l’importance de mesurer la concentration de l’ethanol dans plusieurs echantillons post mortem lorsqu’il est mis en evidence dans le sang, afin de mettre en evidence d’eventuels artefacts lies au processus de redistribution post mortem.

Objectif Depuis de nombreuses annees, la politique en matiere de drogues est basee en Suisse sur quatre piliers, a savoir la prevention, la therapie, la repression et la reduction des risques. Parmi les actions mises en œuvre concernant la reduction des risques lies aux consommations recreatives de substances psychoactives, une nouvelle offre a ete proposee depuis 2019 a Geneve, consistant en l’analyse sur base anonyme et gratuite pour l’usager, d’echantillons destines a etre consommes par celui qui demande l’analyse. L’objectif de ce travail est d’obtenir une vue synthetique des resultats des echantillons soumis a analyse apres 9 mois d’activite. Methode Les echantillons (poudre, comprime, gelule, papier buvard, liquide) sont recueillis lors d’un entretien avec des specialistes de la prevention et de l’accompagnement. Ils sont ensuite transmis au laboratoire de maniere anonyme. Selon le type d’echantillon une solution methanolique est preparee a 1 mg/ml. Systematiquement, cette solution est analysee par chromatographie gazeuse couplee a la spectrometrie de masse apres injection directe, ainsi qu’apres evaporation et acetylation. L’identification des spectres de masse est realisee par comparaison des resultats avec les donnees contenues dans des bibliotheques de references. La solution est egalement systematiquement analysee par chromatographie liquide couplee a la spectrometrie de masse en tandem, afin de determiner la concentration de cocaine, d’amphetamine, de methamphetamine, de MDEA, de MDMA, de 4-MEC, de MDPV, de mephedrone, de methylone, de DOB, de 2C-B, d’heroine, de LSD et de ketamine. Une analyse complementaire de la solution methanolique peut etre effectuee par chromatographie liquide couplee a la spectrometrie de masse en haute resolution, pour confirmer l’identification des substances par comparaison des resultats avec des donnees contenues dans une bibliotheque de reference. Resultats Au total, 115 echantillons ont ete analyses (78 poudres, 20 comprimes, 9 papiers buvard, 7 liquides et 1 gelule). Dans 97 echantillons la substance annoncee a ete detectee ; alors que pour 8 echantillons, aucune substance (absence de pic significatif) n’a ete mise en evidence, et pour 10 autres echantillons, le resultat des analyses ne correspondait pas qualitativement au produit annonce. Les substances les plus frequemment mises en evidence sont la cocaine (n = 44), la MDMA (n = 24), le LSD (n = 9), et la ketamine (n = 6). Les autres substances mises en evidence sont la psilocine, la metocine, le 4-ACO-DMT, l’amphetamine, la methamphetamine, la MDA, le 6-APB, le 2C-B, le 2C-E, le 2-Br-4,5-DMPEA, le DMT, le DOB, le DOC, le DOM, la methoxetamine, la clepherone, le CBD, le GHB, le stanozolol, la methadone, le dextromethorphane, l’heroine, la codeine, et l’ethanol. Le taux de purete median de la cocaine est de 69 % ; les substances de coupage mises en evidence sont le levamisole, la phenacetine, la cafeine, la lidocaine le paracetamol et l’ephedrine. Pour la MDMA, le taux de purete median des poudres (n = 10) est de 91 %, et la dose mediane par comprime de MDMA est de 194 mg. Conclusion Les analyses et le dispositif mis en place ont permis d’emettre plusieurs alertes (publiees sur nuit-blanche.ch) concernant soit la qualite des produits, soit une dose elevee de substance, aupres des usagers recreatifs de substances psychoactives. Ces resultats montrent ainsi l’interet de cette approche dans une vision de reduction des risques envers des consommateurs absents des autres dispositifs. En outre, les resultats permettent d’obtenir des informations concernant la dynamique du marche local des produits psychotropes a usages recreatifs, de maniere complementaire aux analyses des seringues usagees, des eaux usees, des saisies de police et des douanes, ainsi que des echantillons biologiques forensiques et cliniques.

Background: Hyphenation of liquid chromatography (LC) with high-resolution mass spectrometry (HRMS) offers the potential to develop broad-spectrum screening procedures from low volumes of biological matrices. In parallel, dried blood spot (DBS) has become a valuable tool in the bioanalysis landscape to overcome conventional blood collection issues. Herein, we demonstrated the applicability of DBS as micro-sampling procedure for broad-spectrum toxicological screening. Methods: A method was developed on a HRMS system in data dependant acquisition (DDA) mode using an extensive inclusion list to promote collection of relevant data. 104 real toxicology cases were analysed, and the results were cross-validated with one published and one commercial screening procedures. Quantitative MRM analyses were also performed on identified substances on a triple quadrupole instrument as a complementary confirmation procedure. Results: The method showed limits of identification (LOIs) in appropriateness with therapeutic ranges for all the classes of interest. Applying the three screening approaches on 104 real cases, 271 identifications were performed including 14 and 6 classes of prescribed and illicit drugs, respectively. Among the detected substances, 23% were only detected by the proposed method. Based on confirmatory analyses, we demonstrated that the use of blood micro-samples did not impair the sensitivity allowing more identifications in the low concentration ranges. Conclusion: A LC-HRMS assay was successfully developed for toxicological screening of blood microsamples demonstrating a high identification power at low concentration ranges. The validation procedure and the analysis of real cases demonstrated the potential of this assay by supplementing screening approaches of reference.

Objectif Evaluer la possibilite de differencier la prise de cannabis legal, defini selon la loi suisse comme contenant moins de 1 % de tetrahydrocannabinol (THC) et pouvant etre riche en cannabidiol (CBD), de la prise de cannabis illegal, defini en Suisse comme contenant un taux de THC egal ou superieur a 1 %, independamment de la teneur en CBD, a partir des concentrations sanguines de THC, 11-OH-THC, THC-COOH et CBD, et urinaires de THC-COOH et de CBD. Methodes Au total, 284 echantillons de sang et 130 echantillons d’urine provenant de personnes suspectees de conduire sous influence et indiquant une prise de cannabis illicite, ainsi que 13 echantillons de sang et 11 echantillons d’urine preleves chez des personnes consommant du cannabis legal, riche en CBD, suivies en addictologie, ont ete inclus dans l’etude. Les analyses ont ete effectuees par des methodes validees, basees sur l’utilisation de la GC-MS et de la LC-MS/MS, avec une limite de quantification fixee a 1 ng/mL pour le THC, le 11-OH-THC et le CBD, et a 5 ng/mL pour le THC-COOH, dans le sang et l’urine. Resultats Parmi les consommateurs de cannabis illicite, 220 presentaient des concentrations sanguines de THC comprises entre 1,0 et 35 ng/mL, toujours superieures aux concentrations de CBD. Cette derniere substance n’a ete mise en evidence que dans 105 echantillons de sang (37 %). Parmi les consommateurs de cannabis legal, le CBD a ete observe dans tous les echantillons de sang, alors que pour 12 cas (92 %), la concentration de CBD etait comprise entre 2,1 et 24 ng/mL, toujours superieure a la concentration de THC. Des resultats similaires ont ete obtenus dans l’urine, entre le THC-COOH et le CBD. Les medianes, ainsi que les ecarts interquartiles, des concentrations des cannabinoides mesurees dans le sang et l’urine de consommateurs de cannabis illicite (THC ≥ 1 %) et de consommateurs de cannabis legal (THC Tableau 1 . En appliquant la legislation suisse en matiere de circulation routiere, 2 consommateurs de cannabis legal presentaient des concentrations de THC superieures a 1,5 ng/mL (valeur limite selon la legislation suisse), respectivement 1,7 et 2,8 ng/mL. Conclusion Parmi les echantillons analyses, les rapports des concentrations sanguines de cannabinoides ont permis de confirmer le caractere illicite ou legal, selon la legislation suisse, du cannabis consomme. En outre, du fait de la presence de THC dans le cannabis legal et selon la dose consommee, il est possible que la concentration sanguine de THC soit superieure a la valeur limite definissant une infraction en matiere de circulation routiere.

Objectif Presentation d’un cas d’intoxication mortelle au Diuron. Description Un homme d’une soixantaine d’annees est retrouve inconscient dans sa voiture a cote d’une ferme. Il est transporte rapidement a l’hopital. Selon le dossier medical du patient, il n’y a pas d’antecedents medicaux connus hormis une consommation excessive d’alcool. Les examens cliniques effectues montrent un pH a 6,54, des lactates, une troponine et une creatinine eleves tandis que les bicarbonates sont tres diminues. La mesure des gaz arteriels indique une hypoxie severe. Apres des manœuvres de reanimation, le patient decede, sans connaitre l’origine de cette acidose metabolique lactique. Suite au deces, une autopsie est ordonnee par le ministere public. Celle-ci revele un œdeme pulmonaire et une stase viscerale generalisee. Des prelevements sont realises en vue d’analyses toxicologiques. Des echantillons preleves lors de l’arrivee du patient a l’hopital sont egalement transmis au laboratoire de toxicologie. Les analyses mettent rapidement en evidence la presence de diuron, un herbicide, dans le sang, la bile et le contenu gastrique. Methodes Un depistage par tests immunologiques est realise dans l’echantillon urinaire puis un screening par GC/MS, HR-LC-MS/MS et LC/DAD et un test au cyanure sont effectues dans l’echantillon de sang. Les substances d’interet toxicologique mises en evidence sont ensuite dosees par methodes chromatographiques. Une analyse de l’ethanol et des volatils dans le sang est effectuee par GC-FID. Resultats Une ethanolemie a 2,42 g/kg a ete mesuree dans le sang preleve lors de l’arrivee aux urgences. Le diuron a ete mis en evidence par LC-DAD et HR-LC-MS/MS dans l’echantillon de sang ante-mortem. Le dosage a ete effectue par LC-DAD dans le sang (4,9 mg/L), la bile (1,7 mg/L) et le contenu gastrique (> 30 mg/L). L’ethylglucuronide a ete mesure a 4,9 ng/mg sur des cheveux de 4 a 5 cm de long, indiquant une consommation excessive d’ethanol dans les 4 a 5 mois precedent le prelevement. Conclusion Le diuron a ete mis en evidence par LC-DAD dans l’echantillon sanguin. Le spectre UV n’etant pas specifique de ce compose, un echantillon a ete analyse par LC-MS/MS haute resolution afin d’obtenir le spectre caracteristique du diuron. La presence de cette substance dans les differentes matrices biologiques indique une ingestion importante de diuron ayant entraine la mort.

Because of the various matrices available for forensic investigations, the development of versatile analytical approaches allowing the simultaneous determination of drugs is challenging. The aim of this work was to assess a liquid chromatography-tandem mass spectrometry (LC-MS/MS) platform allowing the rapid quantification of colchicine in body fluids and tissues collected in the context of a fatal overdose. For this purpose, filter paper was used as a sampling support and was associated with an automated 96-well plate extraction performed by the LC autosampler itself. The developed method features a 7-min total run time including automated filter paper extraction (2 min) and chromatographic separation (5 min). The sample preparation was reduced to a minimum regardless of the matrix analyzed. This platform was fully validated for dried blood spots (DBS) in the toxic concentration range of colchicine. The DBS calibration curve was applied successfully to quantification in all other matrices (body fluids and tissues) except for bile, where an excessive matrix effect was found. The distribution of colchicine for a fatal overdose case was reported as follows: peripheral blood, 29 ng/ml; urine, 94 ng/ml; vitreous humour and cerebrospinal fluid, < 5 ng/ml; pericardial fluid, 14 ng/ml; brain, < 5 pg/mg; heart, 121 pg/mg; kidney, 245 pg/mg; and liver, 143 pg/mg. Although filter paper is usually employed for DBS, we report here the extension of this alternative sampling support to the analysis of other body fluids and tissues. The developed platform represents a rapid and versatile approach for drug determination in multiple forensic media.

Postmortem angiography is becoming increasingly essential in forensic pathology as an adjunct to conventional autopsy. Despite the numerous advantages of this technique, some questions have been raised regarding the influence of the contrast agent injected on the results of toxicological and biochemical analyses. The aim of this study was to investigate the effect of the injection of the contrast agent Angiofil®, mixed with paraffin oil, on the results of postmortem biochemical investigations performed on vitreous humor. Postmortem biochemical investigations were performed on vitreous samples collected from bodies that had undergone postmortem angiography (n = 50) and from a control group (n = 50). Two vitreous samples were analyzed for each group and the results compared. Glucose, urea, creatinine, 3-β-hydroxybutyrate, sodium and chloride were tested. Different values were observed between the first and second samples in each group. However, these differences were not clinically relevant, suggesting that the injection of this contrast agent mixture does not modify the concentration of the analyzed substances in the vitreous humor.

Une part importante de l'accreditation est de prouver la qualite et la fiabilite de la methode analytique utilisee en routine. Le but de la validation est d'etablir que ces methodes analytiques sont appropriees pour leur utilisation. Notre laboratoire de toxicologie medico-legale est accredite depuis 2003. La strategie de validation de la procedure analytique a ete basee sur l'approche proposee par la Societe Francaise des Sciences et Techniques Pharmaceutiques (SFSTP). Dans ce travail, la validation d'une methode, pour la determination simultanee de cocaine (COC), d'anhydroecgoninemethylester (AEME), d'ecgoninemethylester (EME) et de cocathylene (COET) dans les cheveux par GC-CI/MS/MS en utilisant une detection a piege d'ions, apres une hydrolyse acide et une extraction en phase solide automatisee, a ete presentee comme application a cette directive. On a trouve une regression lineaire dans une gamme de concentrations de 0,05-5,00 ng/mg pour la COC, l'EME et le COET, 0,10-5,0 ng/mg pour VAEME. On a estime la limite de detection (LOD) a 0,005 ng/mg pour la COC et le COET, 0,025 ng/mg pour l'EME et 0,05 ng/mg pour l'AEME. L'efficacite de la methode, comme la justesse et la precision, ont ete evaluees en utilisant des echantillons de controles qualites sur la gamme etudiee.

L'incertitude de mesure n'est pas un concept vraiment nouveau. En effet, l'ancienne norme EN 45001 demandait deja d'estimer ce parametre dans les cas ou cela se justifiait. Maintenant la nouvelle norme ISO 17025 va plus loin et demande que l'incertitude de mesure soit determinee chaque fois que deux resultats sont compares. En toxicologie medico- legale, nous nous trouvons dans cette situation : a) lorsque nous devons rendre un resultat en nous basant sur un seuil de positivite (cut-off), b) lors des interpretations en comparant nos resultats avec des valeurs de reference. C'est pourquoi il est important de connaitre le moyen d'estimer ce parametre pour pouvoir l'appliquer dans le domaine de la toxicologie medico-legale ou cette notion est encore peu employee.

Objectif Presenter quelques cas de suspicion de diminution de la capacite a conduire due a la prise d’amphetamines de synthese en Suisse. Description Depuis quelques annees, les nouvelles drogues psychoactives deviennent de plus en plus consommees en Europe [1] . Un des groupes les plus importants est celui des amphetamines de synthese. La consommation de ces substances peut entrainer une incapacite similaire a celle observee apres la consommation d’amphetamine ou de MDMA. Des symptomes neurologiques et psychologiques peuvent alors affecter le comportement et avoir une influence negative sur la capacite a conduire. Methodes Un depistage par tests immunologiques est realise dans l’echantillon urinaire, puis un screening par DBS-LC-MS/MS est effectue dans l’echantillon de sang. Les substances d’interet toxicologique mises en evidence sont ensuite dosees par GC-MS ou LC-MS/MS. L’analyse des amphetamines de synthese detectees est effectuee par DBS-LC-MS/MS ou LLE-GC/MS, la quantification est realisee a l’aide de la methode par ajouts doses, aucun controle de qualite interne adequat n’ayant ete trouve sur le marche a ce jour. Pour chaque cas, un dosage de l’ethanol est effectue dans l’echantillon de sang par GC-FID. Resultats Dans 8 cas de controles routiers et un cas d’accident de la circulation, des amphetamines de synthese ont ete mises en evidence ces six dernieres annees. La 4-MEC, la mephedrone, la methylone sont les composes les plus frequemment retrouves dans ces cas, souvent en association avec d’autres substances telles que la cocaine, les benzodiazepines, l’ethanol et le cannabis. Conclusion L’evaluation de la diminution de la capacite a conduire due a la prise de nouveaux psychotropes de synthese n’est pas evidente a cause du manque d’etudes scientifiques sur les effets de ces substances sur la conduite automobile. En Suisse, il n’existe pas pour ces substances de seuils definissant une incapacite a conduire. Des lors, l’evaluation doit etre effectuee dans le cadre d’une expertise dite des trois piliers (selon la loi suisse), basee sur le rapport de police, le rapport du medecin intervenu peu apres l’evenement et le rapport des analyses toxicologiques. Si ces cas etaient tres rares ces dernieres annees, depuis quelques mois, plusieurs nouveaux psychotropes de synthese ont ete mis en evidence, amenant a se questionner sur l’aspect ephemere de cette observation, ou si au contraire il s’agit d’une augmentation reelle de la consommation de ces substances en Suisse. En outre, ces observations soulignent l’importance pour les laboratoires de rechercher systematiquement la presence de nouvelles substances dans les echantillons soumis a analyse.

Because of the various matrices available for forensic investigations, the development of versatile analytical approaches allowing the simultaneous determination of drugs is challenging. The aim of this work was to assess a liquid chromatography-tandem mass spectrometry (LC-MS/MS) platform allowing the rapid quantification of colchicine in body fluids and tissues collected in the context of a fatal overdose. For this purpose, filter paper was used as a sampling support and was associated with an automated 96-well plate extraction performed by the LC autosampler itself. The developed method features a 7-min total run time including automated filter paper extraction (2 min) and chromatographic separation (5 min). The sample preparation was reduced to a minimum regardless of the matrix analyzed. This platform was fully validated for dried blood spots (DBS) in the toxic concentration range of colchicine. The DBS calibration curve was applied successfully to quantification in all other matrices (body fluids and tissues) except for bile, where an excessive matrix effect was found. The distribution of colchicine for a fatal overdose case was reported as follows: peripheral blood, 29 ng/ml; urine, 94 ng/ml; vitreous humour and cerebrospinal fluid,5 ng/ml; pericardial fluid, 14 ng/ml; brain,5 pg/mg; heart, 121 pg/mg; kidney, 245 pg/mg; and liver, 143 pg/mg. Although filter paper is usually employed for DBS, we report here the extension of this alternative sampling support to the analysis of other body fluids and tissues. The developed platform represents a rapid and versatile approach for drug determination in multiple forensic media.

Background: Dried blood spots (DBS) sampling has gained popularity in the bioanalytical community as an alternative to conventional plasma sampling, as it provides numerous benefits in terms of sample collection and logistics. The aim of this work was to show that these advantages can be coupled with a simple and cost-effective sample pretreatment, with subsequent rapid LC–MS/MS analysis for quantitation of 15 benzodiazepines, six metabolites and three Z-drugs. For this purpose, a simplified offline procedure was developed that consisted of letting a 5-µl DBS infuse directly into 100 µl of MeOH, in a conventional LC vial. Results: The parameters related to the DBS pretreatment, such as extraction time or internal standard addition, were investigated and optimized, demonstrating that passive infusion in a regular LC vial was sufficient to quantitatively extract the analytes of interest. The method was validated according to international criteria in the therapeutic concentration ranges of the selected compounds. Conclusion: The presented strategy proved to be efficient for the rapid analysis of the selected drugs. Indeed, the offline sample preparation was reduced to a minimum, using a small amount of organic solvent and consumables, without affecting the accuracy of the method. Thus, this approach enables simple and rapid DBS analysis, even when using a non-DBS-dedicated autosampler, while lowering the costs and environmental impact.

Here we report the case of a 70-year-old woman who committed suicide by cyanide poisoning. During resuscitation cares, she underwent an antidote treatment by hydroxocobalamin. Postmortem investigations showed marked bright pink discolouration of organs and fluids, and a lethal cyanide blood concentration of 43 mg/L was detected by toxicological investigation. Discolouration of hypostasis and organs has widely been studied in forensic literature. In our case, we interpreted the unusual pink coloration as the result of the presence of hydroxocobalamin. This substance is a known antidote against cyanide poisoning, indicated because of its efficiency and poor adverse effects. However, its main drawback is to interfere with measurements of many routine biochemical parameters. We have tested the potential influence of this molecule in some routine postmortem investigations. The results are discussed.

The present work describes a fast gas chromatography/negative-ion chemical ionization tandem mass spectrometric assay (Fast GC/NICI-MS/MS) for analysis of tetrahydrocannabinol (THC), 11-hydroxy-tetrahydrocannabinol (THC-OH) and 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH) in whole blood. The cannabinoids were extracted from 500 microL of whole blood by a simple liquid-liquid extraction (LLE) and then derivatized by using trifluoroacetic anhydride (TFAA) and hexafluoro-2-propanol (HFIP) as fluorinated agents. Mass spectrometric detection of the analytes was performed in the selected reaction-monitoring mode on a triple quadrupole instrument after negative-ion chemical ionization. The assay was found to be linear in the concentration range of 0.5-20 ng/mL for THC and THC-OH, and of 2.5-100 ng/mL for THC-COOH. Repeatability and intermediate precision were found less than 12% for all concentrations tested. Under standard chromatographic conditions, the run cycle time would have been 15 min. By using fast conditions of separation, the assay analysis time has been reduced to 5 min, without compromising the chromatographic resolution. Finally, a simple approach for estimating the uncertainty measurement is presented.

Introduction In forensic toxicology, cocaine is better known for its powerful stimulating effects of nervous system and its high potential for recreational abuse, than for his therapeutic use. However, cocaine is still use as a topical anesthetic and peripheral vasoconstrictor in surgeries of eye, ear, nose and throat. Last decade, an increase of the presence of cocaine and metabolites in blood samples of drivers suspected to drive under the influence of drugs (DUID) was observed in Switzerland (Augsburger et al., Forensic Sci Int 153 (2005) 11-15; Senna et al., Forensic Sci Int 198 (2010) 11-16). Observed blood concentration ranges of cocaine and benzoylecgonine were 10-925 μg/L and 20-5200 μg/L, respectively. Since 2005, zero-tolerance approach was introduced in the Swiss legislation for different substances, especially cocaine (analytical cutoff: 15 μg/L). Thus, the interpretation often amounts to determine if the concentration is situated above or under the limit. However, it is important for the interpretation to take into account the context and to be critical with the obtained results, at the risk of ending in erroneous conclusions. Methods Systematical toxicological analyses were performed on blood and urine, if available, for 5 DUID cases, as already published (Augsburger et al., Forensic Sci Int 153 (2005)). Positive results were confirmed and drugs were quantified in biological samples by GCMS, GC-MS/MS or LC-MS/MS. Results Administration of cocaine after traffic accident was identified in five cases. All people were admitted to the emergency room because of severe trauma. Maxillofacial surgery was done shortly after admission to the emergency room, involving use of nasal application of cocaine (swab). For all cases, use of cocaine swab was not mentioned in the document filled by the police and by medical staff requested for blood and urine sampling. The information was obtained retrospectively after consultation of the medical records, without precise indication of the application time or dose. Case 1 . A 83-year old man (pedestrian) was hit by a car. Blood (+11h after the accident): cocaine (16 μg/L), benzoylecgonine (370 μg/L). Urine: cocaine (1700 μg/L), benzoylecgonine (560 μg/L). Case 2 . A 84-year old woman (pedestrian) was hit by a car. Blood (+1.5h after the accident): cocaine (230 μg/L), benzoylecgonine (370 μg/L). Urine was not available. Hair (+4 months after the accident): segment 1 (0-2 cm), cocaine not detected; segment 2 (2-4 cm), cocaine: Case 3 . A 66-year old man was involved in a car/car accident. He died 2 hours and 5 minutes after the crash. Blood (+1.5h after the accident): cocaine and metabolites not detected. Blood (+2h after the accident): cocaine (1750 μg/L), benzoylecgonine (460 μg/L). Blood (post-mortem): cocaine (370 μg/L), benzoylecgonine (200 μg/L). Urine (+1.5h after the accident): cocaine not detected. Case 4 . A 57-year old woman on a motor scooter was hit by a car. She died 2 hours and 10 minutes after the crash. Blood (+0.5h after the accident): cocaine and metabolites not detected. Urine (post-mortem): cocaine ( Case 5. A 30-year old man was involved in a car accident. Blood (+4h after the accident): cocaine (29 μg/L), benzoylecgonine ( Conclusion To our knowledge, this is the first description of DUID cases involving therapeutic use of cocaine after an accident. These results indicate that even if a per se law is effective for prosecution case of DUID, a critical interpretation of the results is always needed, especially if a medical intervention occurs after an accident.