Purity estimation of seized stimulant-type new psychoactive substances without reference standards by nitrogen chemiluminescence detection combined with GC-APCI-QTOFMS.

Purity assessment of seized material containing new psychoactive substances (NPS) is complicated without appropriate primary reference standards. Here we present a method for fast quantitative estimation of stimulant-type NPS with use of secondary reference standards, based on gas chromatography nitrogen chemiluminescence detection coupled with atmospheric pressure chemical ionization quadrupole time-of-flight mass spectrometry (GC-NCD-APCI-QTOFMS). Quantification was based on the detector's N-equimolar response to nitrogen and using two external nitrogen-containing calibrators, MDMA for prim- and sec-amines and α-PVP for tert-amines. Sample preparation involved dissolving the seized powdery material in an organic solvent mixture followed by acylation with N-methyl-bis-trifluoroacetamide (MBTFA). The method's between-day accuracy and precision over a five-day period was measured for twenty-eight stimulants: the grand mean equimolarity was 91.9% (CV 5.5%), as compared with primary reference standards. The GC-NCD-APCI-QTOFMS method was applied to the purity estimation of forty-two seized powder samples previously found to contain stimulant-type NPS by appropriate methods. The quantitative results were compared to those obtained by an established method relying on liquid chromatography chemiluminescence detection (LC-CLND), the latter using caffeine as an external calibrator. The mean difference of purity values between the methods was 8.1% (range 0.4-26.7%). The presented method might find use as a tool for instant purity assessment in forensic laboratories.

Quantitative Estimation of 38 Illicit Psychostimulants in Blood by GC-APCI-QTOFMS with Nitrogen Chemiluminescence Detection Based on Three External Calibrators.

A method was developed for quantitative estimation of illicit psychostimulants in blood, with an emphasis on new psychoactive substances, based on gas chromatography nitrogen chemiluminescence detection coupled with atmospheric pressure chemical ionization quadrupole time-of-flight mass spectrometry (GC-NCD-APCI-QTOFMS). Quantitative estimation relied on the NCD's N-equimolar response to nitrogen, using amphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and methylenedioxypyrovalerone as external calibrators for prim-, sec- and tert- amines, respectively. After spiking with 38 stimulants at 3 concentration levels, the donor blood samples were submitted to liquid-liquid extraction at a basic pH followed by acylation with trifluoroacetic anhydride. All but 3 psychostimulants could be analyzed with a limit of quantification (LOQ) of 0.05 mg/L. At LOQ, the coefficient of variation (CV) values for between-day accuracy was 62.3-143.3% (mean, 93.5%; median, 88.5%) and precision 6.6-22.4% (mean, 15.8%; median, 16.1%). In addition, 11 post-mortem blood samples, containing 0.08-2.4 mg/L of amphetamine (n = 5), methamphetamine (n = 4) or MDMA (n = 4), were analyzed by the GC-NCD-APCI-QTOFMS method, and the results were compared with an established electron ionization GC-MS method with appropriate calibration. The agreement between the 2 methods was 62.5-117.3%. Regarding identification, the APCI source permitted detection of the intact precursor ion, or the respective acylation product, for all of the measured compounds. The GC-NCD-APCI-QTOFMS method developed here enables instant quantitative estimation of illicit psychostimulants in blood at reasonable accuracy, without the necessity of possessing the true reference standards for each analyte.

Femoral blood concentrations of flualprazolam in 33 postmortem cases.

Flualprazolam is a novel designer benzodiazepine, structurally related to alprazolam, flubromazolam and triazolam. In the last couple of years, it has been frequently detected in seizures and in forensic cases in Sweden and Finland. However, there is a lack of published blood concentrations for the drug, which presents difficulties when assessing its relevance for the cause of death. A quantitative method for the determination of flualprazolam in post-mortem blood was developed and validated, and subsequently used to analyse samples from 33 deaths previously screened as testing positive for flualprazolam in Sweden and Finland. Most of the cases in the study were accidental deaths (61 %) or suicides (18 %). The median (range) flualprazolam concentration was 18.0 (3.0-68) ng/g. The majority of the deceased were male (82 %) and the median age was 30 years. The median age in the Swedish cases was significantly higher (35 years) than in the Finnish cases (23 years) (p< 0.05). Poly-drug use and particularly the concomitant use of flualprazolam and opioids were very common in the study population. Most of the cases that were positive for flualprazolam were fatal poisonings by a drug (N=23), and in 13 cases, flualprazolam was implicated in the cause of death. Combining the resources of two countries in which all post-mortem toxicology is centralised provided a more comprehensive insight into the toxicology of flualprazolam. Research on novel psychoactive substances, such as flualprazolam, is required in order to be able to provide scientific evidence on the risks of these new substances for drug administration and potential users.

Single-calibrant quantification of seized synthetic opioids by liquid chromatography-chemiluminescence nitrogen detection.

Drug seizures involving a wide variety of emerging new psychoactive substances (NPS) call for new approaches for instant quantification and valuation. Liquid chromatography-chemiluminescence nitrogen detection (LC-CLND) was used in the quantification of opioids with a single secondary standard (caffeine), utilizing the detector's equimolar response to nitrogen. The mean N-equimolarity of CLND for ten fentanyl derivatives and U-47700 by the present LC-CLND method was 96.4% (range 91-101%). The furanylfentanyl samples consisted of 112 powdery samples with a mean (median, range) hydrochloride purity of 13% (4.9%, 0.08-100%). The purity distribution of the furanylfentanyl samples was distinctly bipartite, showing only lower than 9% (N=98) and higher than 60% (N=14) purities. The carfentanil samples consisted of eight brownish sticky samples with a mean (median, range) hydrochloride purity of 0.064% (0.063%, 0.052-0.092%). The U-47700 samples consisted of seven powdery samples with a mean (median, range) hydrochloride purity of 89.0% (100%, 51-100%). The present application to synthetic opioid analysis widens the scope of the established LC-CLND method, previously found useful for single-calibrant quantification of stimulant/hallucinogenic and cannabinoid type of NPS.

Toxic lifespan of the synthetic opioid U-47,700 in Finland verified by re-analysis of UPLC-TOF-MS data.

U-47,700 is a synthetic opioid that emerged on the novel psychoactive substance market a few years ago. After incorporating the substance into the urine UPLC-TOF-MS screening used in post-mortem toxicology, the drug was detected in 10 autopsy cases within routine case work. In all cases, the cause of death was accidental poisoning by U-47,700 alone or in combination with other psychoactive substances. The concentration of U-47,700 in the blood samples ranged between 0.15-2.0 mg/L with a median of 0.30 mg/L. In one of the cases with a U-47,700 concentration of 0.27 mg/L, no other psychoactive substances were detected. The stored TOF-MS analytical data from the year preceding the incorporation of U-47,700 into the screening was reprocessed in order to search for more positive cases. The data-independent acquisition of the original screening allowed for retrospective re-analysis of the full-scan data without additional experiments on the actual sample. The retrospective data-analysis revealed two additional cases positive for U-47,700. The first mention of U-47,700 on a Finnish internet discussion forum was in March 2015. After having been detected in several death cases, the drug was put under national control in November 2016 and the last fatality occurred in 2017. The toxic lifespan of U-47,700 thus lasted for approximately 2 years in Finland. Forensic and clinical laboratories need to rapidly adjust their screening procedures in order to adapt to the continuously expanding field of novel psychoactive substances. Retrospective data-analysis is a practical tool for monitoring the emergence of new substances onto the market.

Quantitative estimation of α-PVP metabolites in urine by GC-APCI-QTOFMS with nitrogen chemiluminescence detection based on parent drug calibration.

Gas chromatography (GC) hyphenated with nitrogen chemiluminescence detection (NCD) and quadrupole time-of-flight mass spectrometry (QTOFMS) was applied for the first time to the quantitative analysis of new psychoactive substances (NPS) in urine, based on the N-equimolar response of NCD. A method was developed and validated to estimate the concentrations of three metabolites of the common stimulant NPS α-pyrrolidinovalerophenone (α-PVP) in spiked urine samples, simulating an analysis having no authentic reference standards for the metabolites and using the parent drug instead for quantitative calibration. The metabolites studied were OH-α-PVP (M1), 2″-oxo-α-PVP (M3), and N,N-bis-dealkyl-PVP (2-amino-1-phenylpentan-1-one; M5). Sample preparation involved liquid-liquid extraction with a mixture of ethyl acetate and butyl chloride at a basic pH and subsequent silylation of the sec-hydroxyl and prim-amino groups of M1 and M5, respectively. Simultaneous compound identification was based on the accurate masses of the protonated molecules for each compound by QTOFMS following atmospheric pressure chemical ionization. The accuracy of quantification of the parent-calibrated NCD method was compared with that of the corresponding parent-calibrated QTOFMS method, as well as with a reference QTOFMS method calibrated with the authentic reference standards. The NCD method produced an equally good accuracy to the reference method for α-PVP, M3 and M5, while a higher negative bias (25%) was obtained for M1, best explainable by recovery and stability issues. The performance of the parent-calibrated QTOFMS method was inferior to the reference method with an especially high negative bias (60%) for M1. The NCD method enabled better quantitative precision than the QTOFMS methods To evaluate the novel approach in casework, twenty post- mortem urine samples previously found positive for α-PVP were analyzed by the parent calibrated NCD method and the reference QTOFMS method. The highest difference in the quantitative results between the two methods was only 33%, and the NCD method's precision as the coefficient of variation was better than 13%. The limit of quantification for the NCD method was approximately 0.25µg/mL in urine, which generally allowed the analysis of α-PVP and the main metabolite M1. However, the sensitivity was not sufficient for the low concentrations of M3 and M5. Consequently, while having potential for instant analysis of NPS and metabolites in moderate concentrations without reference standards, the NCD method should be further developed for improved sensitivity to be more generally applicable.

Development of a GC-APCI-QTOFMS library for new psychoactive substances and comparison to a commercial ESI library.

Gas chromatography coupled to atmospheric pressure chemical ionization quadrupole time-of-flight mass spectrometry (GC-APCI-QTOFMS) was evaluated for the identification of new psychoactive substances (NPS). An in-house high mass resolution GC-APCI-QTOFMS test library was developed for 29 nitrogen-containing drugs belonging mostly to synthetic stimulants. The library was based on 12 intra-day measurements of each compound at three different collision energies, 10, 20 and 40 eV. The in-house library mass spectra were compared to mass spectra from a commercial library constructed by liquid chromatography-electrospray ionization (LC-ESI) QTOFMS. The reversed library search scores between the in-house GC-APCI library and the commercial LC-ESI library were compared once a week during a 5-week period by using data measured by GC-APCI-QTOFMS. The protonated molecule was found for all drugs in the full scan mode, and the drugs were successfully identified by both libraries in the targeted MS/MS mode. The GC-APCI library score averaged over all collision energies was as high as 94.4/100 with a high repeatability, while the LC-ESI library score was also high (89.7/100) with a repeatability only slightly worse. These results highlight the merits of GC-APCI-QTOFMS in the analysis of NPS even in situations where the reference standards are not immediately available, taking advantage of the accurate mass measurement of the protonated molecule and product ions, and comparison to existing soft-ionization mass spectral libraries. Graphical abstract Tandem mass spectra obtained from GC-APCI-QTOFMS are comparable to LC-ESI-QTOFMS library spectra.

Simultaneous identification and quantification of new psychoactive substances in blood by GC-APCI-QTOFMS coupled to nitrogen chemiluminescence detection without authentic reference standards.

A novel platform is introduced for simultaneous identification and quantification of new psychoactive substances (NPS) in blood matrix, without the necessity of using authentic reference standards. The instrumentation consisted of gas chromatography (GC) coupled to nitrogen chemiluminescence detection (NCD) and atmospheric pressure chemical ionization quadrupole time-of-flight mass spectrometry (APCI-QTOFMS). In this concept, the GC flow is divided in appropriate proportions between NCD for single-calibrant quantification, utilizing the detector's equimolar response to nitrogen, and QTOFMS for accurate mass-based identification. The principle was proven by analyzing five NPS, bupropion, desoxypipradrol (2-DPMP), mephedrone, methylone, and naphyrone, in sheep blood. The samples were spiked with the analytes post-extraction to avoid recovery considerations at this point. All the NPS studies produced a protonated molecule in APCI resulting in predictable fragmentation with high mass accuracy. The N-equimolarity of quantification by NCD was investigated by using external calibration with the secondary standard caffeine at five concentration levels between 0.17 and 1.7 mg/L in blood matrix as five replicates. The equimolarity was on average 98.7%, and the range of individual equimolarity determinations was 76.7-130.1%. The current analysis platform affords a promising approach to instant simultaneous qualitative and quantitative analysis of drugs in the absence of authentic reference standards, not only in forensic and clinical toxicology but also in other bioanalytical applications.

Fatal kavalactone intoxication by suicidal intravenous injection.

Kavalactones are a group of compounds found in kava, a beverage or extract prepared from the rhizome of the kava plant (Piper methysticum). Traditionally kava extracts have been used for their anxiolytic and sedative properties. Sales of kava extracts were severely restricted or prohibited in European countries in 2002 following several cases of serious hepatotoxicity. Here we report a case where high concentrations of kavalactones and ethanol were detected in post mortem femoral blood. An injection needle with a 10-mL syringe containing 7.5 mL of slightly yellowish liquid was found next to the victim, and there were numerous needle prints on both lower arms following the venous tracks. No evidence of other cause of death was found in the medico-legal investigation. The case was therefore classified as suicide using an injection of kavalactones intravenously together with alcohol poisoning.

Straightforward single-calibrant quantification of seized designer drugs by liquid chromatography-chemiluminescence nitrogen detection.

Sixty-one different psychoactive substances were quantified by liquid chromatography-chemiluminescence nitrogen detection (LC-CLND) in 177 samples, using a single secondary standard (caffeine), in a trial concerning the quantitative purity assessment of drug-related material seized by the police in 2011-2012 and customs in 2011-2013 in Finland. The substances found were predominantly substituted phenethylamines, cathinones, tryptamines and synthetic cannabinoids, which were identified by appropriate methods prior to submitting the samples for quantification by LC-CLND. The equimolarity and expanded uncertainty of measurement by LC-CLND were on average 95% and 13%, respectively, based on 16 different substances. The median (mean) purity of stimulant/hallucinogenic drug samples seized at the border was 92.9% (87.6%) and in the street 82.0% (64.5%). The corresponding figures for powdery synthetic cannabinoid samples seized at the border and in the street were 99.0% (96.8%) and 90.0% (92.2%), respectively. There was generally only one active drug to be quantified in each sample. Seized herbal samples contained 0.15-9.2% of between one and three components. LC-CLND was found to be suitable for quantification of the nitrogen-containing drugs encountered in the study, showing sufficient N-equimolarity for both stimulant/hallucinogenic drugs and synthetic cannabinoids. The technique possesses great potential as a standard technique in forensic laboratories.

A rare case of serial killing by poisoning.

A case of serial killing by poisoning by a 59-year-old practical nurse is discussed. Following a report by an emergency-room doctor of an attempted murder, police performed an investigation into all deaths of patients in the nurse's care. Earlier, a medico-legal cause-of-death investigation had been performed on two of these cadavers, but in the other three cases the death certificate had been issued after a medical investigation only. In two of these latter cases, the body had been cremated, but fixed histological samples taken at medical autopsy were available, while in one case the person had died recently and the body was thereafter exhumed and autopsied. All of the suspected victims were older people who required nursing, and the nurse's course of action was consistent in all cases. In the absence of ordinary post-mortem toxicology samples in the medical cases, extraordinary evidence--paraffin-embedded liver tissue samples originally taken for histology at autopsy--was successfully recovered in two cases and analyzed for drugs. In all five cases, drugs not prescribed to the patient were detected, including digoxin, dixyrazine, citalopram, venlafaxine, and benzodiazepines (diazepam, chlordiazepoxide, temazepam, and oxazepam). The nurse was eventually found guilty of five murders by poisoning, five attempted murders, and three aggravated assaults. The nurse was sentenced to life imprisonment.

Absorption of different oral dosage forms of oxycodone in the elderly: a cross-over clinical trial in patients undergoing cystoscopy.

PURPOSE: To characterize the pharmacokinetics (PK) of oxycodone following intravenous injection and administration of three oral dosage forms (solution, capsule, and controlled-release tablet) in elderly patients (age 76-89 years) undergoing cystoscopy. METHODS: This was an open, randomized study with two sequences and two visits in 15 elderly patients. The patients were given intravenous injection (over 10 min) of 5 mg of oxycodone hydrochloride trihydrate. Oxycodone hydrochloride (5 mg in all forms) was orally administered as a solution, a capsule, and a controlled-release tablet. Venous blood samples were collected up to 17 h after oxycodone administration. Population PK parameters were calculated with NONMEM VI 2.0. For intravenous injection we calculated clearance, volume of distribution at steady state, and the half-life of elimination, and for oral dosage forms also the absolute bioavailability. RESULTS: Clearance of the intravenous injections was 28.9 L/h; the volume of distribution at steady state and the half-life of elimination were 186 L and 5.2 h, respectively. The absolute bioavailability of oxycodone was 59 % from oral solutions, 64 % from capsules, and 55 % from controlled-release tablets. CONCLUSIONS: Our results indicate that, in the elderly, the bioavailability of the three different oral dosage forms of oxycodone is fairly similar.

Analgesic concentrations of oxycodone--a prospective clinical PK/PD study in patients with laparoscopic cholecystectomy.

The analgesic concentrations of oxycodone in acute post-operative pain management have not been established. Here, we have evaluated the minimum effective concentration (MEC) and the minimum effective analgesic concentration (MEAC) of oxycodone in pain after laparoscopic cholecystectomy (LCC) in 23 adult patients. The patients were provided with 0.1 mg/kg of oxycodone i.v. 10-15 min. before the end of surgery. After surgery, when the wound pain at rest was ≥3/10 and/or ≥5/10 during wound compression, a first blood sample was obtained (MEC). A second blood sample was obtained after titration with 2 mg i.v. of oxycodone to wound pain <3/10 at rest and <5/10 during wound compression (MEAC). A third blood sample was obtained at the recurrence of the wound pain (the second MEC), and the final blood sample when pain relief was obtained a second time (the second MEAC). At the first onset of pain (MEC), mean P-oxycodone was 21 ng/mL (95% CI 13-29 ng/mL). At the first pain relief (MEAC), P-oxycodone was 55 ng/mL (19-91 ng/mL). The second MEC was 34 ng/mL (11-57 ng/mL), and the second MEAC was 47 ng/mL (14-80 ng/mL). In conclusion, the estimated MEC, 20-35 ng/mL, and MEAC, 45-50 ng/mL, values of P-oxycodone in patients after LLC were significantly higher than those proposed previously. Early pain after LCC appeared to be a feasible method to estimate the analgesic efficacy of oxycodone in acute pain management.

Urine analysis of 3,4-methylenedioxypyrovalerone in opioid-dependent patients by gas chromatography-mass spectrometry.

A gas chromatography-mass spectrometry (GCMS) procedure was developed for the quantitative analysis of the new designer drug methylenedioxypyrovalerone (MDPV) in urine together with the common stimulants amphetamine, methamphetamine, and methylenedioxymethamphetamine (MDMA). The procedure involved electron ionization (EI) GCMS in the selected ion monitoring (SIM) mode after liquid-liquid extraction with toluene and derivatization with heptafluorobutyric acid anhydride. All MDPV findings were confirmed by positive chemical ionization GCMS in SIM mode. Positive chemical ionization-GCMS allowed the protonated molecule M+H+ m/z 276 to be used as a target ion with 3 abundant fragments as qualifier ions. By electron ionization-GCMS, the limit of quantification (LOQ) for MDPV was 0.02 mg/L; and for amphetamine, methamphetamine, and MDMA, the LOQ was 0.05 mg/L. The method was applied to monitoring urine samples from opioid-dependent patients undergoing opioid substitution treatment. Nine of the 34 urine samples (26%) analyzed were MDPV positive by the GCMS procedure. The positive samples were obtained from 2 female and 7 male patients with a mean age of 31 years. The median (range) MDPV concentration was 0.16 mg/L (0.04-3.9 mg/L) based on the 7 samples for which a numeric value was obtained, whereas the concentration was below the LOQ but above the limit of detection in 2 samples. The method revealed amphetamine in approximately 40% of the cases, and there was no statistical difference between the MDPV-positive and MDPV-negative groups. Urine amphetamine concentrations were on average 10 times higher than those of MDPV. The opioid-dependent patients used MDPV mainly as a substitute for amphetamine, judging from the laboratory findings of this study and the information from our patients.

Fatal venlafaxine poisonings are associated with a high prevalence of drug interactions.

Venlafaxine (VEN) is an antidepressant found to possess a higher fatal toxicity index (FTI, i.e., deaths in proportion to consumption) than other newer antidepressants and selective serotonin reuptake inhibitors (SSRIs). The aim of this study was to elucidate using post-mortem cases whether the apparent high toxicity of VEN is associated with adverse drug interactions, pharmacogenetic factors and/or the manner of death. Within a 2-year period, a comprehensive post-mortem database and death certificates were searched for cases with laboratory findings of VEN, findings of other drugs, associated background information and the cause and manner of death. In 123 cases, the concentrations of VEN and its two metabolites, O-desmethylvenlafaxine (O-VEN) and N-desmethylvenlafaxine (N-VEN), and the CYP2D6 genotype were determined in post-mortem blood. The median concentrations of VEN, O-VEN and N-VEN were 560, 420 and 49 µg/l, respectively. A prominent feature of the VEN-positive cases was the high abundance of interacting drugs (46%), being more common with higher VEN concentrations. Compared to other common antidepressants, VEN-positive cases showed the highest suicide frequency, but also the proportion of suicidal VEN poisonings of all suicides was substantially higher than that of mirtazapine or SSRIs. Relative CYP2D6 activity did not predispose to high VEN concentrations, and the frequency of the extreme phenotypes followed the general population. In conclusion, the high suicide potential of VEN in combination with the high prevalence of drugs causing adverse interactions could be the reason for the observed high FTI.

Elevated formic acid concentrations in putrefied post-mortem blood and urine samples.

Formic acid (FA) concentration was measured in post-mortem blood and urine samples as methyl formate using a headspace in-tube extraction gas-chromatography-mass-spectrometry method. A total of 113 cases were analyzed, each including a blood and urine sample fortified with 1% sodium fluoride. The cases were divided into three groups: regular (n=59), putrefied (n=30), and methanol-positive (n=22) cases. There was no evidence of ante-mortem methanol consumption in the regular and putrefied cases. In regular cases, the mean (and median) FA concentrations were 0.04 g/l (0.04 g/l) and 0.06 g/l (0.04 g/l) in blood and urine, respectively. In putrefied cases, the mean (and median) FA concentrations were substantially higher, 0.24 g/l (0.22 g/l) and 0.25 g/l (0.15 g/l) in blood and urine, respectively. In three putrefied cases, FA concentration in blood exceeded 0.5 g/l, a level associated with fatal methanol poisoning. Ten putrefied cases were reanalyzed after 3-4 months storage, and no significant changes in FA concentrations were seen. These observations suggest that FA was formed by putrefaction during the post-mortem period, not during sample storage when sodium fluoride was added as a preservative. In methanol-positive cases, the mean (and median) FA concentrations were 0.80 g/l (0.88 g/l) and 3.4 g/l (3.3 g/l) in blood and urine, respectively, and the concentrations ranged from 0.19 to 1.0 g/l in blood and from 1.7 to 5.6 g/l in urine. The mean (and median) methanol concentrations in methanol-positive cases were 3.0 g/l (3.0 g/l) and 4.4 g/l (4.7 g/l) in blood and in urine, respectively. The highest methanol concentrations were 6.0 g/l and 8.7 g/l in blood and urine, respectively. No ethyl alcohol was found in the methanol-positive blood samples. Poor correlation was shown between blood and urine concentrations of FA. Poor correlations were also shown, in both blood and urine, between methanol and FA concentrations.

Headspace in-tube extraction gas chromatography-mass spectrometry for the analysis of hydroxylic methyl-derivatized and volatile organic compounds in blood and urine.

A novel headspace in-tube extraction gas chromatography-mass spectrometry (ITEX-GC-MS) approach was developed for broad-scale analysis of low molecular weight organic compounds in blood and/or urine. One sample was analyzed following in-vial derivatization with dimethyl sulfate for ethylene glycol (EG), glycolic acid (GA), formic acid (FA), other hydroxylic compounds, and another sample for underivatized volatile organic compounds. Tenax adsorbent resin was used in the microtrap, and a porous layer, open tubular GC capillary column was used for separation. MS was operated in the full-scan mode, identification was based on the Automated Mass Spectral Deconvolution and Identification System, and quantification was based on extracted ions. The limits of quantification for EG, GA, and FA in blood were 10, 50, and 30 mg/L, respectively, and the expanded uncertainties of measurement were 20%, 16%, and 14%, respectively. The procedure allowed for the first time the inclusion of EG and GA as their methyl derivatives within a quantitative HS analysis. The ITEX method described here was more sensitive for analysis of volatile organic compounds than the corresponding static headspace analysis as demonstrated for 11 representative compounds.

Adverse interaction of warfarin and paracetamol: evidence from a post-mortem study.

PURPOSE: The aim of the study was to establish the prevalence and nature of potential adverse drug combinations of warfarin in a large post-mortem toxicology database. The concomitant use of warfarin and non-steroidal anti-inflammatory drugs (NSAIDs) was of interest as these drugs have been associated with internal bleeding both in clinical and post-mortem study settings. Another purpose was to obtain facts related to the questioned safety of warfarin-paracetamol and warfarin-tramadol combinations. METHODS: The post-mortem database was searched for a 1-year period. All warfarin-positive cases and cases containing interacting drugs, as defined by the SFINX interaction database (Swedish, Finnish, Interaction X-referencing), were included. For controls, all cases containing paracetamol or tramadol were also included, and for each warfarin-positive case, an age-, sex- and alcohol-matched control case was sourced. The contribution of anticoagulant use to the deaths was evaluated from the death certificates based on medico-legal autopsies. RESULTS: In 33% of the 328 warfarin-positive cases, at least one interacting drug was present, and paracetamol was the most abundant, accounting for 49% (n = 53). When paracetamol and warfarin were detected simultaneously, the number of fatal bleeds was 4.6 and 2.7 times higher compared to paracetamol or warfarin use alone respectively. The presence of an NSAID in combination with warfarin was rare, as only six cases were identified. A majority (66%) of the post-mortem blood samples had a warfarin concentration below 0.5 mg/l, and for the rest of the cases, the mean concentration was 0.70 mg/l. CONCLUSIONS: This study supports the clinical evidence suggesting that warfarin-paracetamol interactions may create significant life-threatening conditions. It also accentuates the significant role post-mortem database research can have in improving drug safety.

Screening for basic drugs in hair of drug addicts by liquid chromatography/time-of-flight mass spectrometry.

Hair analysis in forensic and clinical toxicology has been strongly focused on drugs of abuse, and comprehensive, drug class-independent screening methods based on mass spectrometric detection have not been applied to date. In this study, a qualitative drug screening method by liquid chromatography coupled to time-of-flight mass spectrometry, earlier developed and evaluated for forensic toxicological urine analysis, was adapted for screening of basic drugs in hair. The method included alkaline hydrolysis, purification with mixed-mode solid phase extraction, and analysis by liquid chromatography coupled to time-of-flight mass spectrometry with automated data analysis and reporting. Identification was based on accurate mass, isotopic pattern fit, and retention time, if available. Analysis of 32 hair samples from deceased drug addicts revealed 35 different drugs. The drug classes identified included antidepressants, antipsychotics, antiepileptics, amphetamines, opioids, beta-blockers, a benzodiazepine, a hypnotic, a local anesthetic, an antiemetic, and an antipyretic analgesic. The findings were in good agreement with the findings in blood and urine by other methods. Moreover, information about previous drug use not evident in the analysis of other matrices was obtained in the majority (72%) of the cases. Tramadol was an especially predominant finding, suggesting tramadol abuse as an opioid substitute. One apparent false-positive finding was identified. The mean and median mass accuracies of positive findings were 2.3 and 1.8 ppm, corresponding to 0.5 and 0.4 mDa, respectively. Cutoff values for tramadol and methamphetamine in hair were 100 and 200 pg/mg, respectively. The method proved to be a simple and straightforward tool for comprehensive screening of basic drugs in hair.