Journal of analytical toxicology最新文献

Liquid chromatography-mass spectrometry (LC-MS) methods for detection of multiple drugs of abuse (DoA) in oral fluid (OF) samples are being implemented in many clinical routine laboratories. Therefore, there is a need to develop new multi-analyte methods with simple sample pre-treatment and short analysis times. The purpose of this work was to validate a method detecting 58 DoA to be used with two different OF sampling kits, the saliva collection system (SCS) from Greiner Bio-One and Quantisal from Immunalysis, using the same sample pretreatment and analytical method. A set of 110 samples collected with the SCS kit was further compared to an LC-HRMS (high resolution mass spectrometry) method in another laboratory. The method was successfully validated, with precision and accuracy of ≤15% and z-scores of <2 for external controls. Using a sensitive LC-MS/MS instrument, the detection limits were <1 µg/L in neat oral fluid. In the comparative study between the LC-MS/MS and LC-HRMS methods using SCS samples, a good agreement was observed. Discrepancies were limited to lower concentration ranges, attributable to differences in cut-off thresholds between the methods. This work contributes to the development of LC-MS multi-analyte methods for OF samples, which are suitable for clinical routine laboratories.

Natural toxins present an ongoing risk for human exposure that requires a rapid, accurate diagnosis for proper response. In this study, a qualitative liquid chromatography high resolution mass spectrometry (LC-HRMS) method was developed and validated for the detection of a large, diverse selection of natural toxins. Data-dependent acquisition was performed to identify compounds with an in-house mass spectral library of 129 hazardous toxins that originate from plants, animals, and fungi. All 129 compounds were spiked into human urine, extracted, and evaluated for spectral library matching. Of these, 92 toxins met the quality criteria and underwent validation in urine matrix based on American National Standards Institute (ANSI) guidelines. A generalized workflow for method expansion was developed and enables the rapid addition of relevant compounds to the established method. This LC-HRMS method achieves efficient detection of natural toxins in urine, and the created workflow can rapidly increase compound coverage via method expansion.

A blind quality control (BQC) program in blood alcohol analysis was implemented at the Houston Forensic Science Center (HFSC) in September 2015. By mimicking authentic toxicology blood evidence, the laboratory can perform a concurrent evaluation of their technical and administrative casework procedures and test the accuracy and reliability of their volatile analysis method in a format that is blinded to the analyst. From September 2015 to November 2023, HFSC's Quality Division submitted 1228 antemortem whole blood samples: 292 ethanol-negative samples and 936 ethanol-positive samples at sixteen target concentrations (0.051, 0.080, 0.100, 0.110, 0.120, 0.130, 0.150, 0.160, 0.170, 0.180, 0.190, 0.200, 0.230, 0.240, 0.250, and 0.260 g/dL). A second, unopened blood tube in 168 of the 1228 BQCs was also analyzed after 721-1140 days: 24 ethanol-negative samples and 144 ethanol-positive samples at five target concentrations (0.080, 0.100, 0.130, 0.180, and 0.240 g/dL). All 316 ethanol-negative samples remained negative. After 42-758 days, the average (median, range) change in ethanol concentration of the 936 positive samples was -1.4% (-1.3%, -12.0% to +8.4%) with a statistically significant difference (P < 0.001) observed for the gradual decline in blood alcohol concentration (BAC) over time. The average BAC percentage differences per target concentration, ranged from -6.4% (-0.008 g/dL) to +5.7% (+0.011 g/dL), were within HFSC's current measurement uncertainty (9.4% at k=3), showing no apparent correlation between the change in ethanol and the theoretical target concentration. As the analysis time between the two blood specimens from the same evidence kit extended, the loss in ethanol significantly increased (P < 0.001).

Protonitazene is a synthetic benzimidazole opioid of the nitazenes class, developed in the 1950s as an effective analgesic, but never released on the market due to severe side effects and possible dependence. Despite its increasing use as a new psychoactive substance starting in 2019, its detection in human hair of intoxicated and deceased consumers has never been reported. We present the development and validation of a specific procedure to identify protonitazene in hair by liquid chromatography with tandem mass spectrometry. Drugs were incubated overnight at 40°C in 1 mL borate buffer, pH 9.5 with 20 mg pulverized hair and 1 ng/mg fentanyl-d5 used as internal standard. Drugs were then extracted with a mixture of organic solvents. The chromatographic separation was performed using an HSS C18 column with a 15-min gradient elution. Linearity was verified from 1 to 100 pg/mg. The limit of detection was estimated at 0.1 pg/mg. No interference was noted from a large panel of natural and synthetic opioids, fentanyl derivatives, or other new synthetic opioids. Protonitazene was identified at 70 and >7600 pg/mg in the whole head hair specimens of two male subjects deceased from an acute drug overdose in jail. Protonitazene was also identified at 14 and 54 pg/mg in two living co-prisoners. As nitazenes represent a growing threat to public health in various parts of the world, this method was developed in response to the challenges posed by the identification of this class of substances.

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.

One of the quickest-growing subclasses of novel psychoactive substances is novel synthetic opioids (NSOs), which are categorized as fentanyl analogs (fentalogs) or nonfentanyl opioids that bind to the mu-opioid receptor. Increased detections of NSOs have been observed in the USA. However, limited information on their prevalence outside of the East Coast is available. This study details the prevalence of NSOs, specifically fluorofentanyl, in the biological and drug paraphernalia specimens of accidental overdose deaths in San Francisco in 2022. A recently developed and validated liquid chromatography with tandem mass spectrometry method was utilized for the analysis of >250 NSOs. Out of the 649 accidental overdose deaths in 2022, 617 cases were available for blood analysis, with at least 1 NSO detected in 48 cases (7.8%). Fentalogs were detected in all 48 cases, with fluorofentanyl being detected in 40 cases. In postmortem femoral blood, estimated concentrations of fluorofentanyl ranged from 0.1 to 8.9 ng/mL, and 0.05 to 85 ng/mL in urine. Polysubstance use with NSO was seen with fentanyl (89.6%), methamphetamine (70.8%), cocaine (33.3%), and heroin (18.8%). NSOs, mainly fluorofentanyl, were observed in matched drug paraphernalia. This report documents the migration of fluorofentanyl to the West Coast, specifically California.

Fuel-burning small engines have the potential to emit dangerous and potentially lethal concentrations of carbon monoxide when used in poorly ventilated environments. The North Carolina Office of the Chief Medical Examiner investigated seven cases from 2013 to 2020 involving lethal carbon monoxide from small internal combustion engines. Evaluation of percent carboxyhemoglobin saturation was determined in these case studies as ratios of carboxyhemoglobin to reduced hemoglobin, using HP 8453 and Agilent 8454 UV-Visible Spectrophotometers (Agilent Technologies, Santa Clara, CA, USA). Sources of carbon monoxide included a pressure washer, a propane-powered forklift, an inboard engine boat, a motorcycle, propane and kerosene heaters, and home-use generators. It was demonstrated during a death investigation that the Dräger X-am 2000 electrochemical gas monitor often used by first responders, falsely reacted to acetylene gas, initially misleading investigators to the source of the carbon monoxide. Educating first responders about not only the hazards of these unexpected carbon monoxide sources, but the limitations of their equipment, is a valuable goal of disseminating complete medical examiner case information. The details of these cases will educate first responders, the forensic science community, and public health leaders on potential small engine sources of carbon monoxide in death investigations, responder safety, and the limitations of portable air quality monitoring equipment during death investigation.

Public laboratories must balance innovative and existing methods to keep up with designer drug trends. This article presents a strategy for handling designer benzodiazepines (DBZDs) in casework from screening to interpretation. The cross-reactivity of 22 DBZDs and metabolites was tested against the Immunalysis™ benzodiazepine (BZD) direct enzyme-linked immunosorbent assay kit. The kit had high intra-analyte precision (coefficients of variation <15%). Inter-analyte performance varied, triggering confirmation testing at concentrations ranging from 35 to 460 μg/L. The Cuyahoga County Regional Forensic Science Laboratory implemented a 40-analyte BZD and Z-drug confirmation method in 2019. Ten additional analytes were later validated for qualitative reporting, and the limits of detection for 13 analytes were lowered by 60%. The method of standard addition was also optimized for as-needed quantitation. Equal and 1/x weighting factors correlated well with target concentrations (coefficients of determination (r2) > 0.98), but 1/x weighting provided the most consistently accurate concentrations. Six computational models were developed to predict γ-aminobutyric acid-A receptor binding affinity to assist in case interpretation (r2 > 0.70 for cross-validation and test set prediction). These models were used to predict the binding affinity of analytes in the confirmation method. Other public laboratories can use this same practical strategy to adapt to any designer drug class (e.g., BZDs, opioids, cannabinoids and stimulants).

A simple and rapid qualitative chromatographic method with a unique extraction approach was developed and validated to screen oral fluid samples for 31 compounds in driving under the influence of drugs investigations. The scope and sensitivity of the method meets or exceeds Tier I recommendations established by the National Safety Council's Alcohol, Drugs and Impairment Division. Since this is a targeted chromatographic screen (rather than an immunoassay), cutoffs were set to match the confirmation levels in the recommendations. Sample preparation involved a single-step liquid-liquid extraction procedure, using a mixture of methyl tert-butyl ether, isopropanol, and hexane and was applied to samples collected with the Quantisal™ device. Instrument analysis was conducted by liquid chromatography-tandem mass spectrometry, using a Restek Raptor™ biphenyl column for chromatographic separations and a total run time of 8 min. Validation results met all requirements of ANSI/ASB Standard 036 (1st edition)-Standard Practices for Method Validation in Forensic Toxicology.