Postmortem Toxicology Research Articles

Findings of synthetic cathinones in post-mortem toxicology

Findings of synthetic cathinones in post-mortem toxicology

Comprehensive Study of Various Chemical Samples in Forensic Toxicology: Focus on Urine Sample

Toxicology deals with the measurement and analysis of toxins. It is itself a vast branch of science, though it has several branches and one of these is forensic toxicology. Forensic toxicology is a branch of toxicology that lines up with other disciplines, namely clinical chemistry, postmortem forensic toxicology, human performance toxicology and forensic drug testing, providing medical jurisprudence of adverse effects such as drug abuse, poisoning and death. The key role of forensic toxicology is to identify and analyse the toxin compounds found during adverse events. This review paper aims to draw an idea about the toxin, in the collected biological chemical samples such as urine samples and their effects on their day-to-day life.

Neuropathologic Findings and Electrolyte Abnormalities in a Case of Lennox-Gastaut Syndrome (SCN2a- related) Encountered at Autopsy

Abstract Introduction/Objective Lennox-Gastaut syndrome is a severe form of childhood epilepsy which may be due to several conditions, including sodium channelopathies which alter neuronal firing patterns. We present a case of a 6-year-old female with Lennox-Gastaut syndrome (SCN2A-related) complicated by developmental delay, spastic quadriplegia, and gastrojejunostomy tube dependence who was referred for medicolegal autopsy due to death subsequent to becoming unresponsive during a supervised bath. Methods/Case Report A complete autopsy was performed, including gross and microscopic examination of all primary organ systems, formal neuropathologic examination, and postmortem microbiology, toxicology, and vitreous electrolyte studies. The decedent showed evidence of developmental delay and flexion contractures of the extremities. No significant traumatic injuries were identified. A postmortem nasopharyngeal swab was positive for Rhinovirus/Enterovirus and Influenza A H3. A postmortem vitreous electrolyte panel demonstrated a dehydration pattern, including markedly elevated sodium and chloride and elevated urea nitrogen. Gross examination of the brain showed a thin corpus callosum, small hippocampi, as well as abnormal cerebellar dentate and inferior olivary nuclei. Microscopic examination of the brain tissue supported the gross findings, including dentato-olivary dysplasia. The cause of death was certified as dehydration complicating Lennox-Gastaut syndrome (SCN2a-related). Rhinovirus/Enterovirus and Influenza A H3 infections were considered contributory to death. The manner of death remained undetermined, since it was unknown if the decedent’s natural diseases, issues following a scheduled gastrojejunostomy feeding regimen, neglect, or some combination thereof caused the dehydration. Results (if a Case Study enter NA) NA Conclusion This case highlights unique and rarely documented neuropathologic findings and electrolyte abnormalities that may be seen in Lennox-Gastaut syndrome associated with an SCN2A mutation in addition to demonstrating the challenges of cause and manner death certification in cases of severe developmental disorders of childhood related to sodium channelopathies.

2,4-dinitrophenol intoxication and its morphological findings as an indication of substance intake

Lethal intoxications can only very rarely be recognized during an external examination of corpses, as poisoning does not leave any characteristic findings on the deceased. The present study is a retrospective review on 2,4-dinitrophenol (2,4-DNP) intoxications in human subjects from the beginning of the 20th century until today, as well as a case report on a fatal intoxication of a 50-year old obese man in Rostock (Germany) and an introduction for toxicological analysis in post-mortem specimens of the substance ingested in these rare cases.Via selective literature search, the information on occurrence and localization of abnormal pathomorphological external and/or internal findings in cases of 2,4-DNP ingestion/ intoxication was gathered. By 2021, a total of 13 case reports with information on morphological findings due to 2,4-DNP ingestion/intoxication were found. The external findings were dominated by yellowing of the skin, followed by exanthemas/rashes and yellowing of the sclera. The internal findings included yellowing of the internal organs, yellow color of the stomach contents, yellowing of the mucous membranes and an intense yellow color of the urine. Yellowish discoloration of the skin, sclera, mucous membranes, internal organs, sweat and/or an intensive yellow discoloration of the urine are not observed in every 2,4-DNP intoxication. However, when they do occur, they are a characteristic indication of 2,4-DNP ingestion and, if localized to the skin, indicate prolonged consumption. A fatal case from Rostock in 2016 due to prolonged intake of 2,4-DNP for weight loss is exemplified. A simple, fast and cost-effective workup combined with HPLC-DAD for post-mortem toxicology ultimately delivers reliable analysis results.

Analysis of 132 submandibular salivary glands using the Randox Evidence Investigator and Randox DOA ULTRA WB array.

Occasionally, obtaining an adequate or acceptable postmortem blood specimen for drug analysis is not possible due to factors such as decomposition, exsanguination, or embalming. Submandibular salivary gland tissue, one of three major types of salivary gland tissue in the oral cavity of humans, has been reported to be a viable alternative postmortem specimen for toxicological testing. In this study, we evaluated the performance of the Randox Evidence Investigator instrument and Randox DOA (Drugs of Abuse) Ultra Whole Blood Array for the semi-quantitative determination of 21 immunoassays in an alternative matrix, submandibular salivary gland tissue. We analyzed 132 submandibular salivary gland tissue specimens and compared the generated results to concomitantly collected postmortem whole blood specimen results. Oxycodone 2, meprobamate, barbiturate, benzodiazepine assay 1, zolpidem, and buprenorphine all showed perfect agreement (Cohen's kappa score = 1.00) between the submandibular salivary gland tissue results and the postmortem whole blood results; dextromethorphan, fentanyl, benzoylecgonine, methamphetamine, tricyclic antidepressants, oxycodone 1, and opiate showed an almost perfect agreement (Cohen's kappa score = 0.81-0.99); methadone, generic opioids, and amphetamine exhibited substantial agreement (Cohen's kappa score = 0.61-0.80). Tramadol demonstrated fair agreement (Cohen's kappa score = 0.41-0.60). The lowest measure of agreement was observed with cannabinoids, meeting criteria for slight agreement (Cohen's kappa score = 0.01-0.20). An application of the techniques described in this study could be implemented in postmortem toxicology laboratories as well as medical examiners offices to provide preliminary drugs of abuse test results that can be used to direct additional testing. This study highlights the successful integration of a novel specimen matrix and an "off-label" use of an established analytical technique.

The emergence of bromazolam in Jefferson County, AL: a case series.

Postmortem toxicology is an ever-changing landscape presenting challenges for toxicologists and medical examiners. Trends can vary for certain benzodiazepines. While diazepam use tends to remain constant, alprazolam and clonazepam ebb and flow depending on prescription trends and street popularity. Novel benzodiazepines like etizolam vary in casework depending on legal restrictions and black market availability. In May 2022, the first case of the designer benzodiazepine, bromazolam, was detected in Jefferson County Coroner/Medical Examiner's Office casework. Between then and December 2023, an additional nine cases have been observed. Bromazolam is the brominated analog of the low-dose benzodiazepine, alprazolam, and is likely similar in potency. As bromazolam is a potent benzodiazepine, low concentrations of this novel drug are likely to contribute to central nervous system depression in opioid overdose cases. We present 10 cases in which bromazolam was detected in postmortem samples at the University of Alabama at Birmingham toxicology laboratory. The decedents ranged in age from 20 to 41 years. Most of the decedents were White (n = 8; 80%) and male (n = 7; 70%). Bromazolam concentrations ranged from 21 to 3220 ng/mL (mean 401 ng/mL). All but one case were polydrug, and all deaths were related to drug toxicity. Fentanyl was detected in 8 of the 10 decedents, with concentrations ranging from <2.5 to 97 ng/mL (mean 30 ng/mL). Additional drugs detected were methamphetamine, ethanol, oxycodone, methadone, cocaine, amphetamine, morphine, and diphenhydramine. While all manners of death were ruled as accidental, bromazolam was included in the cause of death statements in 9 of the 10 cases. Capturing important emerging drug trends in the death certificate is critical to help inform public health and medical colleagues for preventive measures and treatment in the continued drug epidemic.

Ethanol concentrations in various biological specimens: Living and postmortem forensic toxicology analysis and comprehensive literature review

Alcohol use upsurges the risk for many chronic ill-health consequences such as hepatitis, malignancies, and disastrous outcomes like road traffic accidents ending in fatal injuries. Biochemical and toxicological analysis of different body fluids is crucial for identifying the cause of death and postmortem interval in many forensic cases. Blood, urine, and vitreous fluid are the most valuable body fluids for detecting alcohol during any toxicological analysis. Alcohol is responsible for widespread morbidity and mortality worldwide. Blood alcohol concentration (BAC) is a necessary toxicological test to investigate various crime and accident scenes. This study comprehensively explores the demographic characteristics, BAC distribution, and correlations of alcohol concentrations in postmortem and living cases. Postmortem cases (N = 166) reveal intriguing demographic patterns, with notable variations in year distribution, nationality, sex, age groups, occupation, smoking habits, place of death, and psychiatric history. Living cases (N = 483) exhibit distinct demographic profiles, emphasizing differences in year distribution, nationality, sex, age groups, and smoking habits.Analysis of BAC distribution reveals diverse patterns in both postmortem and living cases, providing valuable insights into the prevalence of different BAC levels in each group. Correlation analyses unveil strong associations between alcohol concentrations in various biological samples in postmortem cases, highlighting the interdependence of blood, vitreous, and urine alcohol concentrations. Conversely, living cases display a moderate positive correlation between blood and urine alcohol concentrations.Comparative analyses showcase significant differences in mean alcohol concentrations between postmortem and living cases, suggesting variations in alcohol metabolism and distribution. These findings underscore the importance of considering temporal factors in interpreting alcohol concentrations in forensic and clinical contexts.In conclusion, this study enhances our understanding of alcohol-related incidents by delineating demographic profiles, BAC distributions, and correlations between different biological samples. Such insights are crucial for refining investigative and clinical approaches, contributing to the broader fields of forensic science and public health.

Assessment of Δ9-THC and Δ9-THCCOOH bias, precision, and ionization suppression/enhancement between solid tissue homogenate and supernatant by LC-MS-MS.

Liquid chromatography-triple quadrupole mass spectrometry (LC-MS-MS) assays are frequently utilized for screening and confirmatory purposes in the forensic toxicology laboratory. While these techniques are excellent for the targeted identification and quantitation of a wide variety of drug classes, validation and determining fit-for-purpose is a significant requirement for each method. In the USA, the American National Standards Institute and Academy Standards Board first edition of Standard 036 currently serves as a primary resource in forensic toxicology method validation and mandates that laboratories evaluate critical performance characteristics to help ensure the production of forensically defensible results. Due to the variability of specimen quality frequently encountered in the discipline of postmortem toxicology, the State of Maryland Office of the Chief Medical Examiner Forensic Toxicology Laboratory routinely analyzes solid tissue specimens as part of the medicolegal death investigation process and evaluates liver as a representative solid tissue matrix during method validation. Authentic postmortem specimens (e.g. liver, kidney, skeletal muscle, and spleen) were used to investigate the effects of analyzing solid tissue homogenate versus solid tissue supernatant on bias, precision, and ionization suppression/enhancement of Δ9-THC and Δ9-THCCOOH. Bias was <20% for Δ9-THC and Δ9-THCCOOH in liver homogenate and supernatant with a single exception of the low QC concentration for Δ9-THC in liver homogenate (-29%). Within-run and between-run CV was <20% for Δ9-THC and Δ9-THCCOOH in liver homogenate and supernatant. Δ9-THC and Δ9-THC-d3 exhibited significant ion suppression in both liver homogenate and supernatant, while Δ9-THCCOOH and Δ9-THCCOOH-d3 showed both ion suppression and enhancement in these matrices. Noticeable quantitative differences were observed in authentic postmortem solid tissue homogenate and supernatant specimens despite evaluating identical tissue samplings. A brief discussion of the results is presented using a validated LC-MS-MS method for the confirmation and quantitation of Δ9-THC and Δ9-THCCOOH in postmortem casework.

M27 - The NIDA Cause of Death Elucidated (CODE) Initiative: Developing Innovative Postmortem Toxicology Testing Devices to Reduce the Undercounting of Drug Overdose Deaths

M27 - The NIDA Cause of Death Elucidated (CODE) Initiative: Developing Innovative Postmortem Toxicology Testing Devices to Reduce the Undercounting of Drug Overdose Deaths

A QSAR-based application for the prediction of lethal blood concentration of new psychoactive substances

The rapid development and introduction of new psychoactive substances (NPS) into illegal markets present an enormous challenge for forensic toxicologists, as there is limited knowledge about their toxicity in humans. To strengthen forensic interpretation of NPS intoxication cases, we have developed a predictive model for estimating human lethal blood concentrations (LBC) of various NPS. This quantitative structure-activity relationship (QSAR) model focuses on opioids, designer benzodiazepines, synthetic cathinones, synthetic cannabinoids, and phenethylamines. Utilising linear regression and multilayer perceptron algorithms, the models was trained using data from the existing literature. A toxicological significance-based approach have been applied to refine the selection of training data. The model demonstrated satisfactory performance metrics through cross-validation (R ≈ 0.8, MAE ≈ 0.6) and comparison with experimental data (R ≈ 0.9). A Python-based web application have been developed to facilite the use of the created model in predicting LBC of NPS. Despite the model's reliability, limitations due to data availability, quality and the complexities of post-mortem toxicology mean that its predictions should be interpreted with caution.

Buprenorphine deaths confirmed by toxicology reveal a low proportion of opioid agonist treatment before death in Finland.

We studied opioid agonist treatment (OAT) status before buprenorphine-related death in Finland, where buprenorphine is the principal OAT medicine and also the most misused opioid, through a retrospective population-based study using medico-legal cause-of-death investigation and OAT patient records. The study included all death cases (N = 570) between 2018 and 2020 with a buprenorphine or norbuprenorphine finding in post-mortem toxicology and with known drug misuse history or concomitant findings of illicit drugs. Of the deceased, 10% had received OAT in the year before death. Less than 1% of individuals < 25 years had received OAT, whereas the proportion in individuals ≥ 25 years was 13% (p < 0.001). There were significantly more females and more fatal poisonings (p < 0.001) among those < 25 years than among those ≥ 25 years. OAT medication at the time of death was sublingual buprenorphine-naloxone in 74% and subcutaneous buprenorphine in 23%. Except for significantly fewer benzodiazepine findings among those receiving OAT, minimal differences were found in terms of age, gender, cause and manner of death, or concomitant substance use between the deceased in and outside of OAT. Concomitant misuse of benzodiazepines, psychostimulants, alcohol, and gabapentinoids was frequent both in and outside of OAT and likely contributed to the death. These results suggest that access to OAT especially for young people and treatment of multiple addictions should be improved. Comprehensive information from medico-legal cause-of-death investigation as a starting point, combined with subsequent ante-mortem patient records, proved to be a successful approach to shed light on the Finnish scene of buprenorphine mortality.

Elucidating the Gas-Phase Behavior of Nitazene Analog Protomers Using Structures for Lossless Ion Manipulations Ion Mobility-Orbitrap Mass Spectrometry.

2-Benzylbenzimidazoles, or "nitazenes", are a class of novel synthetic opioids (NSOs) that are increasingly being detected alongside fentanyl analogs and other opioids in drug overdose cases. Nitazenes can be 20× more potent than fentanyl but are not routinely tested for during postmortem or clinical toxicology drug screens; thus, their prevalence in drug overdose cases may be under-reported. Traditional analytical workflows utilizing liquid chromatography-tandem mass spectrometry (LC-MS/MS) often require additional confirmation with authentic reference standards to identify a novel nitazene. However, additional analytical measurements with ion mobility spectrometry (IMS) may provide a path toward reference-free identification, which would greatly accelerate NSO identification rates in toxicology laboratories. Presented here are the first IMS and collision cross section (CCS) measurements on a set of fourteen nitazene analogs using a structures for lossless ion manipulations (SLIM)-orbitrap MS. All nitazenes exhibited two high intensity baseline-separated IMS distributions, which fentanyls and other drug and druglike compounds also exhibit. Incorporating water into the electrospray ionization (ESI) solution caused the intensities of the higher mobility IMS distributions to increase and the intensities of the lower mobility IMS distributions to decrease. Nitazenes lacking a nitro group at the R1 position exhibited the greatest shifts in signal intensities due to water. Furthermore, IMS-MS/MS experiments showed that the higher mobility IMS distributions of all nitazenes possessing a triethylamine group produced fragment ions with m/z 72, 100, and other low intensity fragments while the lower mobility IMS distributions only produced fragment ions with m/z 72 and 100. The IMS, solvent, and fragmentation studies provide experimental evidence that nitazenes potentially exhibit three gas-phase protomers. The cyclic IMS capability of SLIM was also employed to partially resolve four sets of structurally similar nitazene isomers (e.g., protonitazene/isotonitazene, butonitazene/isobutonitazene/secbutonitazene), showcasing the potential of using high-resolution IMS separations in MS-based workflows for reference-free identification of emerging nitazenes and other NSOs.

Assessment of urine drug screen utility at autopsy to predict laboratory postmortem blood toxicology.

When faced with increasing drug-related deaths and decline in practicing forensic pathologists, the need to quickly identify toxicology-related deaths is evident in order to appropriately triage cases and expedite turnaround times. Lateral flow immunoassays conducted pre-autopsy offer quick urine drug screen (UDS) results in minutes and are used to inform the need for autopsy. Over 1000 medicolegal cases were reviewed to compare UDS results to laboratory enzyme-linked immunosorbent assay (ELISA) blood results to evaluate how well autopsy UDS predicted laboratory findings. Mass spectral analysis was performed on ELISA-positive specimens and these data were used to investigate UDS false-negative (FN) results when possible. Five different UDS devices (STAT One Step Drug of Abuse dip card and cassette, Premiere Biotech multi-drug and fentanyl dip cards and ATTEST 6-acetylmorphine (6-AM) dip card) were tested encompassing 11 drug classes: 6-AM, amphetamine/methamphetamine, benzodiazepines, benzoylecgonine, fentanyl, methadone, opioids, phencyclidine, and delta-9-tetrahydrocannabinol. Sensitivity, specificity, efficiency, and positive and negative predictive values >80% indicated that UDS was useful for predicting cases involving benzoylecgonine, methadone, methamphetamine, and phencyclidine. UDS was unreliable in predicting amphetamine, benzodiazepines, fentanyl, and opiates-related cases due to a high percentage of FN (up to 11.2%, 8.0%, 12.4%, and 5.5%, respectively) when compared to ELISA blood results. For the later analytes, sensitivities were as low as 57.5%, 60.0%, 72.2%, and 66.7%, respectively. Overall results support that UDS cannot replace laboratory testing. Because UDS is subject to false-positive and FN results users must understand the limitations of using UDS for triage or decision-making purposes.

Detection of the benzodiazepine bromazolam by liquid chromatography with quadrupole time of flight mass spectrometry in postmortem toxicology casework and prevalence in Indiana (2023).

For the past 60 years, benzodiazepines such as chlordiazepoxide, diazepam, and alprazolam have been used as pharmaceutical medications for the treatment of myriad conditions including anxiety, seizures, and insomnia. In more recent years, novel benzodiazepine derivatives have emerged as illicit substances in powders and counterfeit tablets on the illicit drug market. In 2016, bromazolam, a brominated derivative of alprazolam, emerged on the illicit drug market in Europe, but the substance was not reported in the USA until 2019-2020. In this study, we report the emergence and subsequent prevalence of bromazolam in postmortem blood in the state of Indiana during 2023. Analysis was completed by a solvent protein precipitation extraction with acetonitrile and detection by liquid chromatography with quadrupole time of flight mass spectrometry. During 2023, bromazolam was detected in 94 cases across 25 counties in Indiana. It was never the sole substance detected and was commonly detected alongside fentanyl (83 cases), norfentanyl (77 cases), 4-anilino-N-phenethylpiperidine (76 cases), acetylfentanyl (49 cases), methamphetamine (32 cases), naloxone (25 cases), 11-nor-9-carboxy-tetrahydrocannabinol (24 cases), and benzoylecgonine (20 cases). After official query with the Indiana Department of Health, it was found that bromazolam was specifically included in the cause of death certification in 31 fatalities (32.9%). Due to the scarcity of information regarding this novel benzodiazepine derivative in postmortem toxicology and its involvement in fatalities, it is important that forensic toxicology laboratories consider adding bromazolam to their comprehensive scope of analysis.

Difficulties associated with the interpretation of postmortem toxicology.

While postmortem (PM) toxicology results provide valuable information towards ascertaining both the cause and manner of death in coronial cases, there are also significant difficulties associated with the interpretation of PM drug levels. Such difficulties are influenced by several pharmacokinetic and pharmacodynamic factors including PM redistribution, diffusion, site-to-site variability in drug levels, different drug properties and metabolism, bacterial activity, genetic polymorphisms, tolerance, resuscitation efforts, underlying conditions, and the toxicity profile of cases (i.e. single- or mixed-drug toxicity). A large body of research has been dedicated for better understanding and even quantifying the influence of these factors on PM drug levels. For example, several investigative matrices have been developed as potential indicators of PM redistribution, but they have limited practical value. Reference tables of clinically relevant therapeutic, toxic, and potentially fatal drug concentrations have also been compiled, but these unfortunately do not provide reliable reference values for PM toxicology. More recent research has focused on developing databases of peripheral PM drug levels for a variety of case-types to increase transferability to real-life cases and improve interpretations. Changes to drug levels after death are inevitable and unavoidable. As such, guidelines and practices will continue to evolve as we further our understanding of such phenomena.

When Vaping Isn't Actually Safer: A Death From Toxic Alcohol Contaminated Vape Juice.

Vape juice is a diluent for e-cigarette active ingredients, nicotine or tetrahydrocannabinol (THC). Lack of strict regulation in vape juice production is a concern as ingredients and their concentrations may vary widely from the labeling.A 43-year-old woman was transported via ambulance to the hospital after ingesting homemade vape juice, presenting unresponsive with decerebrate posturing. She reportedly made a tincture combining a vape juice purchased online (containing "ethylene glycol") and THC for "endometriosis-related pain relief." Laboratory evaluation revealed anion gap metabolic acidosis, elevated serum lactate, and high serum osmolality. Urine fluoresced under Wood's lamp, and fomepizole was administered as an ethylene glycol antidote, but she expired the following afternoon. Clinical serum toxicology results returned after death revealed 235 mg/dL of methanol, and no ethylene glycol.Autopsy findings included ischemic changes of the gastrointestinal tract and cerebral edema with herniation. Postmortem toxicology performed on hospital admission blood revealed methanol (220 mg/dL), propylene glycol (59 mg/dL), Δ-9 THC and metabolites, and medications administered during hospitalization. The medical examiner determined the cause of death to be methanol and propylene glycol toxicity.To our knowledge, this is the first report of accidental death from ingestion of vape juice contaminated with toxic alcohol.

Risk of adverse outcomes during gabapentinoid therapy and factors associated with increased risk in UK primary care using the clinical practice research datalink: a cohort study.

Growing evidence from pharmacovigilance data and postmortem toxicology reports highlights the misuse potential of gabapentinoids. This study aimed to investigate the risk of serious adverse outcomes (drug misuse, overdose, major trauma), and their risk factors, in primary care patients who are prescribed gabapentinoids. Using the UK Clinical Practice Research Datalink, a matched cohort study calculated adverse event rates separately for gabapentinoid-exposed and unexposed cohorts. In the exposed cohort, event rates for exposure to a range of potential risk factors were calculated. Event rates were compared using Cox proportional hazards models, adjusted for age, sex, deprivation, previous mental health diagnosis, and coprescribing with potentially interacting medicines. Substance misuse (gabapentin adjusted hazard ratio [95% CI]: 2.40 [2.25-2.55]), overdose (2.99 [2.56-3.49]), and major trauma (0-2.5 years: 1.35 [1.28-1.42]; 2.5 to 10 years: 1.73 [1.56-1.95]) were more common among patients prescribed gabapentinoids than matched individuals who were not. The association with overdose was stronger for pregabalin than gabapentin. All adverse outcomes were significantly associated with smoking, history of substance misuse, overdose, or a mental health condition and prescription of opioids, benzodiazepines, antidepressants, and Z-drug hypnotics (eg, gabapentin hazard ratios for association of concurrent opioid use: misuse 1.49 [1.47-1.51]; overdose 1.87 [1.78-1.96]; major trauma 1.28 [1.26-1.30]). Our findings highlight the importance of careful patient selection when prescribing gabapentinoids and the need to educate prescribers about the risks of these drugs, particularly in combination with other central nervous system depressants.

Concentration units used to report blood- and breath-alcohol concentration for legal purposes differ between countries which is important to consider when blood/breath ratios of alcohol are compared and contrasted.

This technical note reviews the plethora of concentration units used to report blood-alcohol concentration (BAC) and breath-alcohol concentrations (BrAC) for legal purposes in different countries. The choice of units sometimes causes confusion when scientific papers originating from a certain country might be introduced into evidence via expert testimony, such as when alcohol-related crimes are prosecuted. The concentration units are also important to consider when blood/breath ratios (BBRs) of alcohol are calculated and compared between countries. Statutory BAC limits for driving in most nations are reported in mass/volume (m/v) units, such as g/100 mL (g%) in the United States, mg/100 mL (mg%) in the United Kingdom and Republic of Ireland, or g/L (mg/mL) in many EU nations. By contrast, Germany and the Nordic countries report BAC as mass/mass (m/m) units, hence g/kg or mg/g, which are ~5.5% lower than m/v units, because whole blood has an average density of 1.055 g/mL. There are historical reasons for reporting BAC in mass/mass units because the aliquots of blood analyzed were measured by weight rather than volume. The difference between m/m and m/v is also important in postmortem toxicology, such as when distribution ratios of ethanol between blood and other biological specimens, such as urine, vitreous humor, and cerebrospinal fluid, are reported.

Analysis of over 250 novel synthetic opioids and xylazine by LC-MS-MS in blood and urine.

Novel Synthetic Opioids (NSO) are frequently found in postmortem (PM) and human performance (HP) forensic toxicology casework, resulting in impairment and fatal overdoses. Developing a broad NSO method benefits public health, as it can be used to identify trends in potent opioid use to develop risk management programs. This project aimed to design a comprehensive, rapid and routine method for the selective analysis of over 250 novel synthetic opioids in blood and urine. This method rapidly extracted 150 µL of blood or urine via protein precipitation followed by size-exclusion filtration, evaporation and reconstitution. Separation and data acquisition were achieved on a 12 min LC-MS-MS method using an F5 column. Data processing was expedited with a custom built-in query created in-house that automated processing and enhanced quality assurance. Validation according to ASB/ANSI Standard 036 was performed and applicability of the method was assessed using proficiency test and authentic casework samples. Assessed in blood and urine qualitatively were 261 unique analytes including fentanyl analogs (fentalogs), nitazenes and other miscellaneous synthetic opioids. As 59 isomeric target analytes were placed into groups due to co-elution, there were 202 distinct acquired targets or target - groups. To demonstrate applicability, 27 proficiency test blood samples received over an approximate 4-year period were analyzed with 126 expected results assessed comprising 25 unique target analytes. Additionally, 617 fatal accidental overdoses within San Francisco in 2022 were retroactively analyzed by this method with almost 10% of cases containing a new NSO substance(s). Such trends and NSO substances were previously unknown in this community.

Prevalence and blood concentrations of benzodiazepines and opioids in opioid-positive death investigations in Ontario, Canada, from 2017 to 2021.

The aim of this study was to investigate the incidence of benzodiazepines in opioid-positive death investigations, including trends in frequency and combination of drugs, as well as demographic data and blood concentrations, where available. Additionally, naloxone concentrations in polysubstance compared to opioid-only cases were analyzed. This was a retrospective study that consisted of all post-mortem toxicology cases in Ontario, Canada, from January 01, 2017, to December 31, 2021, with an opioid finding in any analyzed autopsy specimen. There were 11,033 death investigations identified. The overall rate of benzodiazepine co-involvement was 54.5%. Males accounted for the majority of cases (71%), and the most affected age group was 30- to 39-year-olds. The most frequently detected opioid was fentanyl and the most frequently detected benzodiazepine was etizolam, which was also the most frequently observed opioid/benzodiazepine combination. Findings related to differences in concentrations of opioids when naloxone was also present were mostly non-significant, except for methadone. The rate of benzodiazepine detection with opioids grew faster than opioid detections overall, potentially due to the increasingly toxic drug supply. Detection of novel psychoactive drugs fluctuated more unpredictably than opioids and benzodiazepines associated with clinical use. These findings can help inform policy decisions by public health agencies in exploring harm reduction efforts, for example, education and drug-checking services.