Postmortem reference concentrations of 68 elements in blood and urine.

INTRODUCTION: Fatal intoxications, both accidental and intentional, are a global issue. In the Western world, intoxications with pharmaceuticals dominate, but in other parts of the world, other substances are more common. In a forensic setting, elemental intoxications are of great importance when investigating both accidental, suicidal, and homicidal deaths. The current study presents normal postmortem reference concentrations of 68 elements in femoral blood and urine. In addition, possible sources of error such as contamination from sample tubes, preservative potassium fluoride (KF) solution, and storage time are evaluated. METHODS: Paired femoral blood and urine samples from 120 cases of death by suicidal hanging in Sweden were collected. Additionally, multiple batches of sample tubes and multiple batches of KF solution were also analyzed. Concentrations of elements were determined by double focusing sector field ICP-MS. RESULTS: Key descriptive statistics for 68 elements are provided in blood and urine. Contamination from sample tubes was minor compared to the overall mean elemental concentrations in both blood and urine. KF solution contained a large assortment of elements, but the overall contribution is relatively minor for most elements given the small amounts of solution added to samples. There were significant differences for 22 elements in blood and 17 elements in urine between samples with short and long storage time. CONCLUSION: The present study provides an important tool when evaluating postmortem elemental concentrations. It fills a needed gap between large antemortem population studies and postmortem case reports or small case series of elemental intoxications.

Post-Mortem Metabolomics: A Novel Approach in Clinical Biomarker Discovery and a Potential Tool in Death Investigations.

Metabolomics can be defined as the scientific field aiming at characterizing all low-weight molecules (so-called metabolites) in a biological system. At the time of death, the level and type of metabolites present will most likely reflect the events leading up to death.In this proof of concept study, we investigated the potential of post-mortem metabolomics by identifying post-mortem biomarkers, correlated these identified biomarkers with those reported in clinical metabolomics studies, and finally validated the models predictability of unknown autopsy cases. In this post-mortem metabolomics setting, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry data from 404 post-mortem samples, including pneumonia cases and control cases, were processed using XCMS (R). Potential biomarkers were evaluated using principal component analysis and orthogonal partial least squares-discriminant analysis. Biomarkers were putatively annotated using an in-house database and the online databases METLIN and HMDB. The results showed that clear group separation was observed between pneumonia cases and control cases. The metabolites responsible for group separation belonged to a broad set of biological classes, such as amino acids, carnitines, lipids, nicotinamides, nucleotides, and steroids. Many of these metabolites have been reported as important in clinical manifestation of pneumonia. For the unknown autopsy cases, the sensitivity and specificity were 86 and 84%, respectively. This study successfully investigated the robustness and usability of post-mortem metabolomics in death investigations. The identified post-mortem biomarkers correlated well with biomarkers reported and identified through clinical research.

Fatal Intoxications with Zopiclone-A Cause for Concern?

INTRODUCTION: Zopiclone, a controlled substance prescribed for insomnia, has become a common toxicological finding in forensic autopsy cases. This study investigated the role and extent of zopiclone use in fatal intoxications in Sweden. METHODS: All forensic autopsy cases positive for zopiclone in femoral blood during 2012-2020 were selected. Among these cases, fatalities caused by intoxication according to the cause of death certificates issued by the forensic pathologist were identified. Intoxications where zopiclone contributed to the cause of death were included in the study. The Swedish Prescribed Drug Register was utilized to examine whether the included cases were prescribed zopiclone or not. RESULTS: In total 7320 fatal intoxications underwent a forensic autopsy during the study period, 573 of them were caused by zopiclone. Among the zopiclone fatalities, 87% (n = 494) had a prescription for zopiclone, and 8% (n = 43) were monointoxications. Most fatalities, 62% (n = 354) were suicides, and zopiclone was involved in about 17% (n = 354) of all intoxication suicides in Sweden. Women were significantly (p < 0.01) overrepresented in suicides with zopiclone, comprising 56% (n = 291) of fatalities. The median age was 55 years among zopiclone intoxications compared with 44 years amongst all fatal intoxications. CONCLUSION: This study demonstrates that the toxicity of zopiclone can be lethal both in combination with other substances and on its own. Most individuals dying in fatal zopiclone intoxications were prescribed zopiclone, which potentially indicates that a more restrictive prescribing rate could prevent future intoxication deaths, especially when caring for patients with an increased suicide risk.

Postmortem metabolomics as a high-throughput cause-of-death screening tool for human death investigations.

Autopsy rates are declining globally, impacting cause-of-death (CoD) diagnoses and quality control. Postmortem metabolomics was evaluated for CoD screening using 4,282 human cases, encompassing CoD groups: acidosis, drug intoxication, hanging, ischemic heart disease (IHD), and pneumonia. Cases were split 3:1 into training and test sets. High-resolution mass spectrometry data from femoral blood were analyzed via orthogonal-partial least squares discriminant analysis (OPLS-DA) to discriminate CoD groups. OPLS-DA achieved an R2 = 0.52 and Q2 = 0.30, with true-positive prediction rates of 68% and 65% for training and test sets, respectively, across all groups. Specificity-optimized thresholds predicted 56% of test cases with a unique CoD, average 45% sensitivity, and average 96% specificity. Prediction accuracies varied: 98.7% for acidosis, 80.5% for drug intoxication, 81.6% for hanging, 73.1% for IHD, and 93.6% for pneumonia. This study demonstrates the potential of large-scale postmortem metabolomics for CoD screening, offering high specificity and enhancing throughput and decision-making in human death investigations.

Postmortem Metabolomics Reveal Acylcarnitines as Potential Biomarkers for Fatal Oxycodone-Related Intoxication.

Postmortem metabolomics has recently been suggested as a potential tool for discovering new biological markers able to assist in death investigations. Interpretation of oxycodone concentrations in postmortem cases is complicated, as oxycodone tolerance leads to overlapping concentrations for oxycodone intoxications versus non-intoxications. The primary aim of this study was to use postmortem metabolomics to identify potential endogenous biomarkers that discriminate between oxycodone-related intoxications and non-intoxications. Ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry data from 934 postmortem femoral blood samples, including oxycodone intoxications and controls positive and negative for oxycodone, were used in this study. Data were processed and evaluated with XCMS and SIMCA. A clear trend in group separation was observed between intoxications and controls, with a model sensitivity and specificity of 80% and 76%. Approximately halved levels of short-, medium-, and long-chain acylcarnitines were observed for oxycodone intoxications in comparison with controls (p < 0.001). These biochemical changes seem to relate to the toxicological effects of oxycodone and potentially acylcarnitines constituting a biologically relevant biomarker for opioid poisonings. More studies are needed in order to elucidate the potential of acylcarnitines as biomarker for oxycodone toxicity and their relation to CNS-depressant effects.

Postmortem Metabolomics of Insulin Intoxications and the Potential Application to Find Hypoglycemia-Related Deaths.

Postmortem metabolomics can assist death investigations by characterizing metabolic fingerprints differentiating causes of death. Hypoglycemia-related deaths, including insulin intoxications, are difficult to identify and, thus, presumably underdiagnosed. This investigation aims to differentiate insulin intoxication deaths by metabolomics, and identify a metabolic fingerprint to screen for unknown hypoglycemia-related deaths. Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry data were obtained from 19 insulin intoxications (hypo), 19 diabetic comas (hyper), and 38 hangings (control). Screening for potentially unknown hypoglycemia-related deaths was performed using 776 random postmortem cases. Data were processed using XCMS and SIMCA. Multivariate modeling revealed group separations between hypo, hyper, and control groups. A metabolic fingerprint for the hypo group was identified, and analyses revealed significant decreases in 12 acylcarnitines, including nine hydroxylated-acylcarnitines. Screening of random postmortem cases identified 46 cases (5.9%) as potentially hypoglycemia-related, including six with unknown causes of death. Autopsy report review revealed plausible hypoglycemia-cause for five unknown cases. Additionally, two diabetic cases were found, with a metformin intoxication and a suspicious but unverified insulin intoxication, respectively. Further studies are required to expand on the potential of postmortem metabolomics as a tool in hypoglycemia-related death investigations, and the future application of screening for potential insulin intoxications.

Pathogenic role of cardiac mast cell activation/degranulation,TNF-alpha, and cell death in acute drug-related fatalities.

BACKGROUND: Intravenous injection of narcotic stimulants affects many cellular functions relevant for the pathophysiological mechanisms of heart failure. There is considerable evidence that mast cells (MCs), TNF-alpha, and cell death play crucial roles in the pathogenesis and progression of cardiac arrest. In this study, we examined and compared the participation of MCs, TNF-alpha, apoptosis and necrosis in the heart of drug-related fatalities and the victims of sudden death due to the cardiac failure or aortic dissection. METHODS AND RESULTS: Serum level of postmortem tryptase was determined in all study subjects that consisted of 50 autopsy cases: 30 drug overdose fatalities which were further divided into two groups with high and low level of tryptase, and 20 cases of sudden natural death (SND). The distribution profile of cardiac infiltrated-MCs and production patterns of TNF and C9 (necrotic marker) were investigated immunohistochemically. In situ-detection of apoptosis with TUNEL was applied to the heart sections. The level of tryptase was elevated (>45 microg/L) in the drug fatalities but remained below the cut-off value in SND. In the myocardium of overdose victims, MC-infiltration and degranulation were significantly increased as well as production of myocytic TNF-alpha compared with the SND cases. The expressions profile of myocytic TNF varied between the groups. Apoptotic myocytes were seen more frequently in the SND group while necrosis was more evident in the heart of drug-related fatalities. CONCLUSION: Mast cells are recruited and activated in the heart of drug-associated deaths and the myocytes are the main source of TNF-alpha with the ability of different production patterns. The high degree of MC degranulation and the elevated levels of tryptase together with the pathological changes in heart of drug-related victims resemble that of the anaphylactic deaths as demonstrated in our previous study.

Reference values of lithium in postmortem femoral blood.

INTRODUCTION: The main recipients of lithium, people diagnosed with bipolar disorder, show an increased mortality in both natural and unnatural causes of death. Based on international data persons diagnosed with bipolar disorder comprise 2.3-9.6% of all suicidal deaths. In cases of suicide among those suffering from bipolar disorder, 17-53% are due to fatal intoxications. Diagnosing fatal intoxications is often challenging, particularly when the reference information needed to interpret the concentration of a drug is lacking or scarce. AIM: The aim of this study was to establish postmortem femoral blood reference concentrations of lithium, providing both fatal and "normal" postmortem concentrations, as well as to investigate the impact of the mode of intoxication and to study the co-detection of lithium and antidepressant drugs in intoxications and controls. METHOD: In Sweden, forensic autopsies are performed in unnatural and obscure deaths. This study included all autopsies in which lithium was found during the study period (1992-2010). Lithium was not included in the regular drug screen, but analysed upon request using flame photometry, ion-selective electrode detection or atomic absorption spectrophotometry. Each case was evaluated according to an established strategy, with strict inclusion and exclusion criteria followed by a multi-observer manual review (Fig. 1, Table 1). The cases included were classified as single intoxications (group A), multi-drug intoxications (group B) or controls (group C). The control group only included cases where death by intoxication and antemortem incapacitation by drugs could be ruled out. RESULTS AND DISCUSSION: During the study period, lithium was found in 124 cases. After application of inclusion and exclusion criteria and the subsequent manual review, 21 cases were classified as group A (n=4), group B, (n=7) and group C (n=10). The femoral blood lithium concentrations in group A (median 2.69mmol/l) and group B (median 2.10mmol/l) were significantly different (p=0.01) compared to group C (median 0.2mmol/l). There were however no statistically significant difference between the concentrations in groups A and B. The most common mode of death in intoxications was acute-on-chronic (n=10), but the impact of chronic use on the fatal blood concentrations could not be evaluated since there was just one case without previous use. There was no difference in the proportion of co-detections of lithium and antidepressants between intoxication cases and controls.

Antipsychotics - Postmortem fatal and non-fatal reference concentrations.

Making the diagnosis fatal intoxication is a challenging task for the forensic pathologist and toxicologist, particularly when the cases involve substances where reference information is scarce or not at all available. This study presents postmortem femoral blood concentrations for 24 antipsychotic substances, based on samples collected and analyzed from 4949 autopsy cases in Sweden during 1992-2010. In addition our study provides information about the prevalence of different antipsychotics in accidental, suicidal, homicidal and uncertain deaths. The data have been selected and evaluated according to strict inclusion and exclusion criteria as well as a manual, multi-reviewer, case-by-case evaluation. The reference information is subdivided into intoxications by one specific substance only (group A, n=259), multi-substance intoxications (group B, n=614) and postmortem controls, consisting of deaths not involving incapacitation by substances (group C, n=507). Moreover, the results are compared with data based on therapeutic drug monitoring, and data collected from driving under the influence cases. Median concentrations in group A were significantly higher than in group C for all substances evaluated. For 17 of 24 substances, the median concentrations in group B were significantly higher than in group C. In general, the therapeutic drug monitoring and driving under the influence concentrations were similar to, or lower than, the concentrations in group C.

Sedative and hypnotic drugs--fatal and non-fatal reference blood concentrations.

In postmortem investigations of fatal intoxications it is often challenging to determine which drug/s caused the death. To improve the interpretation of postmortem blood concentrations of sedative and hypnotic drugs and/or clonazepam, all medico-legal autopsies in Sweden - where these drugs had been detected in femoral vein blood during 1992-2006 - were identified in the databases of the National Board of Forensic Medicine. For each drug, concentrations in postmortem control cases - where the cause of death was not intoxication and where incapacitation by drugs could be excluded - were compiled as well as the levels found in living subjects; drugged driving cases and therapeutic drug monitoring cases. Subsequently, fatal intoxications were assessed with regards to the primary substances contributing to death, and blood levels were compiled for single and multiple drug intoxications. The postmortem femoral blood levels are reported for 16 sedative and hypnotic drugs, based on findings in 3560 autopsy cases. The cases were classified as single substance intoxications (N=498), multiple substance intoxications (N=1555) and postmortem controls (N=1507). Each autopsy case could be represented more than once in the group of multiple intoxications and among the postmortem controls if more than one of the included substances were detected. The concentration ranges for all groups are provided. Overlap in concentrations between fatal intoxications and reference groups was seen for most substances. However, the concentrations found in single and multiple intoxications were significantly higher than concentrations found in postmortem controls for all substances except alprazolam and triazolam. Concentrations observed among drugged drivers were similar to the concentrations observed among the therapeutic drug monitoring cases. Flunitrazepam was the substance with the highest number of single intoxications, when related to sales. In summary, this study provides reference drug concentrations primarily to be used for improving interpretation of postmortem drug levels in obscure cases, but which also may assist in drug safety work and in pharmacovigilance efforts.

Perfil ambiental de América Latina y El Caribe

Se compara la situación ambiental y los factores que inciden sobre el ambiente en América Latina y El Caribe, con la situación en otras regiones del planeta. Permite establecer patrones para ciertos indicadores e identificar la necesidad de obtener mas información sobre ciertos renglones, para poder realizar una evaluación mas completa. El trabajo puede servir de base para el desarrollo de estrategias a nivel de la región y el trasfondo para determinar el exito o el fracaso de estrategias de protección ambiental y uso regional de los recursos naturales

Perfil ambiental de América Latina y El Caribe

Se compara la situación ambiental y los factores que inciden sobre el ambiente en América Latina y El Caribe, con la situación en otras regiones del planeta. Permite establecer patrones para ciertos indicadores e identificar la necesidad de obtener mas información sobre ciertos renglones, para poder realizar una evaluación mas completa. El trabajo puede servir de base para el desarrollo de estrategias a nivel de la región y el trasfondo para determinar el exito o el fracaso de estrategias de protección ambiental y uso regional de los recursos naturales