Journal of analytical toxicology最新文献

Alpha-2 adrenergic receptor agonists are established therapeutic medications that are used for conditions such as hypertension, pain disorders, muscle relaxation, spasticity, opioid withdrawal, insomnia, and sedation. While forensic toxicologists may be familiar with more common alpha receptor agonists, tizanidine is a less frequently identified compound, with limited published data available regarding antemortem and postmortem concentrations. Tizanidine therapeutic concentrations found in plasma are reported in the range of 0.0025-0.025 mg/L, although CYP1A2 inhibitors can significantly raise tizanidine levels in the body, thereby increasing the risk of dose-related toxicity. Additionally, imidazoline receptor activity is an underappreciated contributor to the mechanism of action and potential for adverse effects of this drug. Due to its high potency, tizanidine may be missed by forensic laboratories that are not targeting this drug or carefully inspecting untargeted data for its presence. In this study, 18 postmortem cases involving tizanidine are reviewed to improve the understanding of its forensic toxicological profile. These cases have been divided into categories as ruled by the certifying pathologist of "Suicide" involving tizanidine (N = 8, mean 6.2 mg/L and median 0.77 mg/L) and "Accident" involving tizanidine (N = 4, mean 0.86 mg/L and median 0.89 mg/L), and additionally a category of "Incidental" (N = 6, mean 0.35 mg/L and median 0.035 mg/L). Comparison of tizanidine concentrations to those in example cases such as this dataset can assist postmortem forensic toxicologists and pathologists in distinguishing therapeutic postmortem concentrations from toxic/lethal concentrations. However, consideration of scene details and totality of case investigation is essential when determining cause and manner of death.

Sevoflurane, a volatile anesthetic routinely used in clinical settings, was investigated to determine the extent of its interference with in-house forensic blood ethanol analysis. This potential interference could have a significant impact on the analysis and subsequently the interpretation of ethanol in human performance antemortem forensic toxicology casework (e.g. Driving While Under the Influence (DWI) cases). Aqueous samples with ethanol concentrations spanning 0.02-0.40 g/100 mL were fortified with sevoflurane and analyzed using two different dual-column headspace--gas chromatography with flame ionization detection instruments. Sevoflurane was found to elute as an interference peak near ethanol on column 1 (BAC1) and co-elute with ethanol on column 2 (BAC2); the differences were due to the column chemistries. Analyte identification and quantification acceptance criteria monitored included peak-to-valley ratio (resolution) and percent difference between individual column concentrations and the average value of both column concentrations. A 2023 DWI case exhibited potential sevoflurane interference and demonstrated the importance of ethanol reporting acceptance criteria for detecting such interference. In the majority of experiments with sevoflurane and ethanol present in the samples, sevoflurane presence caused failing acceptance criteria to report ethanol results, but if acceptance criteria were met, the ethanol concentration was slightly elevated. An additional sevoflurane stability study showed that the highly volatile sevoflurane could evaporate between analysis and re-analysis of blood samples due to additional tube openings. The decrease of sevoflurane was monitored at each opening of the tube using relative peak areas. HFSC re-analyzes suspected sevoflurane samples, as the additional tube openings could allow sevoflurane to evaporate.

Δ9-Tetrahydrocannabinol (THC) is the most frequently used illicit drug in the world, yet interpretation of THC concentrations in driving under the influence of drug (DUID) cases is difficult due to possible residual THC concentrations. This study determined the concentrations of cannabinoids in blood collected across multiple time points from drivers in suspected impaired driving cases to evaluate if changes in concentrations over time can provide clarification on the time of cannabis use. This study examined cannabinoid-positive DUID cases reported from January 2019 to December 2023 to identify those that tested multiple blood draws. Thirty-five cases were identified that had multiple blood draws for a total of 81 different samples with collection times ranging from 00:32 to 12:42 hours between incident and blood draw. Cannabinoid testing was performed using a liquid chromatography-tandem mass spectrometry analysis with reporting limits of 1.0, 5.0, and 0.5 ng/mL for 11-hydroxy-THC (11-OH-THC), 11-nor-9-carboxy-THC (THC-COOH), and THC, respectively. THC concentrations (n = 81) ranged from 0.74 to 40 ng/mL. Eleven samples had an increase in THC concentration at a later collection time point. 11-OH-THC concentrations (n = 60) ranged from 1.0 to 16 ng/mL. THC-COOH concentrations (n = 81) ranged from 7.1 to 470 ng/mL. The results of this study underscore the difficulty in interpretation and drawing conclusions regarding time of cannabis use, even when multiple samples are obtained from the same subject over time from a single incident.

Selective androgen receptor modulators (SARMs) are a new class of substances that have similar properties to anabolic steroid agents, but with marked reduced androgenic properties. As SARMs have the potential to be misused for performance enhancement in sport due to their anabolic properties as well as their ability to stimulate androgen receptors in the muscle and the bone, they have been prohibited at-all-times by the World Anti-Doping Agency (WADA) since 2008 under section S1.2 of the List. Ligandrol is one of the more popular SARMs. A WADA-accredited laboratory identified bishydroxy-ligandrol in the urine of a female athlete, the major ligandrol metabolite at approximately 90 pg/mL (specimen A) and 200 pg/mL (specimen B). The athlete challenged this anti-doping rule violation and requested a hair test to document possible incidental exposure. About 7 weeks after urine collection, a hair specimen (brown in color and > 20 cm in length) was collected and segmented in 6 × 1 cm segments. Ligandrol was tested by liquid chromatography-tandem mass spectrometry after alkaline incubation and extraction. With a limit of quantitation at 1 pg/mg, no ligandrol was identified. It appears that the athlete was unaware her husband was taking the substance, which was confirmed by his hair test (ligandrol at 7 and 8 pg/mg in 2 × 2.5 cm segments). The Court of Arbitration for Sports accepted the athlete's explanation that she had been exposed to ligandrol through the exchange of bodily fluids with her husband and lifted her provisional ban. This case demonstrates that drug transfer between two subjects is possible during intimate moments.

A persistent problem in the detection of novel psychoactive substances (NPS) is the inability of traditional screening methodologies to rapidly adapt to evolving drug trends. As such, high-resolution mass spectrometry (HRMS) screening methods have gained popularity in recent years for the ability to use non-targeted acquisition to detect a wide variety of compounds without necessarily returning to method development. However, these instruments may be unattainable for some forensic laboratories due to the associated high capital costs. The described method provides an alternative screening method using precursor ion scan (PIS) acquisition on a liquid chromatography-tandem mass spectrometry (LC-MS/MS) platform to screen for nitazene analogs. Four ions were evaluated (m/z 72.1, 98.0, 100.1, and 112.1) for d0 analytes and one ion (m/z 104.1) for the metodesnitazene-d4 internal standard. Using a liquid-liquid extraction in whole blood, the method was validated with a 0.5 ng/mL limit of detection and 1.0 ng/mL administrative cutoff. Observed matrix effects did not affect limit of detection and there was no demonstration of carryover or interferences. As a proof-of-concept study, authentic (n = 3) and blind fortified (n = 20) samples were evaluated using this method, which was able to identify all nitazenes with no false negatives or positives. Several nitazenes not initially included in the scope of method development or validation were also presumptively identified. To accommodate this novel instrumental analysis, a workflow is also proposed to assist in the identification of known and emerging nitazene analogs. LC-MS/MS is widely available among forensic laboratories and presents a viable alternative to HRMS screening for nitazene analogs when operated in PIS acquisition, in such cases that HRMS is unavailable for assessing emerging NPS threats.

Medetomidine is an alpha-2 agonist and non-opioid sedative. Its presence in illicit fentanyl and heroin drug supplies poses significant risks to user health caused by cardiac effects and sedation. Medetomidine exists in two enantiomeric forms: dexmedetomidine and levomedetomidine. Dexmedetomidine is used in humans in medical settings, while dexmedetomidine alone and a racemic mixture of dexmedetomidine and levomedetomidine are used in animals in veterinary settings. Little information is known about circulating blood concentrations of medetomidine or its enantiomers in humans in situations involving synthetic opioids (e.g. fentanyl) and other sedatives (e.g. xylazine, benzodiazepines). A new toxicological workflow using liquid chromatography-tandem quadrupole mass spectrometry (LC-QQQ-MS) was developed and validated for the quantitation of medetomidine and the qualitative enantiomeric separation of dexmedetomidine and levomedetomidine. The assays were applied to a case series of 100 authentic specimens from emergency department admissions and forensic postmortem investigations containing medetomidine, fentanyl, xylazine, and metabolites, among other substances. Medetomidine blood concentrations in non-fatal overdoses ranged 0.1-16 ng/mL (median: 1.5 ng/mL) and in fatal overdoses ranged 0.1-32 ng/mL (median: 0.31 ng/mL). Xylazine was co-detected in 76% of cases with higher median concentrations: 8.3 ng/mL (non-fatal) and 15 ng/mL (fatal). Fentanyl was co-detected in 93% of cases with median concentrations of 5.2 ng/mL (non-fatal) and 21 ng/mL (fatal). Dexmedetomidine and levomedetomidine were identified in 90% of cases; the remaining cases were confirmed or suspected medical-setting administration of dexmedetomidine. These findings demonstrate that medetomidine is arising from veterinary or clandestine sources, and we hypothesize the latter. Recreational medetomidine use causes adverse effects such as profound bradycardia and heightened sedation, especially when combined with fentanyl and xylazine. Forensic laboratories must remain aware of adulterants, like medetomidine, appearing in traditional opioid products (e.g. fentanyl, heroin), updating testing methods to capture these emerging adulterants in real-time.

Postmortem forensic toxicology plays a critical role in medicolegal death investigations through the identification and quantitation of drugs and other substances in postmortem fluids and tissues. Due to the complexity of this sub-discipline, consistent application of best practices is critical for ensuring accurate and reliable results, particularly in the context of challenges such as emerging novel psychoactive substances, complex poly-drug interactions, postmortem drug redistribution, and analytical limitations inherent with postmortem specimens. Although there has been significant progress in the development of consensus-based forensic toxicology standards, their scope is intentionally broad to accommodate human performance, postmortem, regulated and non-regulated employment drug testing, court-ordered toxicology, and other applications. Consequently, some aspects specific to postmortem toxicology and medicolegal death investigation are not addressed within the standards. This manuscript seeks to fill these gaps by demonstrating how current standards can be applied in a postmortem toxicology setting and presenting best practices in situations where no established standards exist. These best practices will aid laboratories in prioritizing changes to workflows, allocating resources more efficiently, improving analytical accuracy and reproducibility, ensuring interpretative consistency, and strengthening forensic defensibility in administrative and legal proceedings. Key topics addressed include specimen collection and case submission protocols, method validation approaches tailored for postmortem analysis, optimized analytical workflows based on testing scope and case classification, and quality assurance requirements. Considerations for data review, reporting, and result interpretation are discussed in the context of accurate determination of cause and manner of death. Emphasis is placed on integrating toxicological findings with investigative and autopsy information obtained through ongoing communication with stakeholders. By integrating the application of existing consensus standards with the best community practices for postmortem toxicology, this manuscript aims to support the generation of robust and reliable toxicological data, with the goal of improving forensic investigations, public health surveillance, and drug policy development.

Cannabis use is common, with diversity in cannabis products contributing to difficulty in accurately assessing the impact of cannabis use in vulnerable populations such as emerging adults. This study describes and assesses concurrence across toxicological matrices (oral fluid, plasma, urine, and hair) and self-reported cannabis use days. Further, it examines whether 11-nor-9-carboxy-tetrahydrocannabinol (THCCOOH, the primary metabolite of Δ9-tetrahydrocannbinol [THC]) concentration or use patterns varies by administration route (smoked flower or vaped concentrate) or predicts depression symptoms. Here, cannabis using (n = 70) and non-using (n = 24) adolescents and young adults (64% female; ages 18-21) were asked to contribute oral fluid, blood, urine, and hair for toxicological testing and self-reported past-90 days of cannabis use, including route of administration. Positive and negative toxicological results by matrix are presented, with sensitivity and specificity calculated. Correlations between THCCOOH concentration across matrices and self-report use were run. Analysis of variance models (ANOVAs) tested whether product type (smoked flower v. vaped concentrate) influenced cannabis use patterns, use to avoid withdrawal, or THCCOOH concentration. Regressions assessed cannabis metrics predicting depression symptoms, controlling for biological sex. All matrices demonstrated excellent specificity (100%), with largely adequate sensitivity (63-74%) except for oral fluid (12%). Self-report and toxicological metrics were significantly correlated (r's = .41-.97), except for avoiding withdrawal. THCCOOH concentration across matrices did not differ by route of administration group; groups also did not differ by self-reported use days or avoiding withdrawal symptoms (p's = .16-.66). Only plasma THCCOOH concentration predicted depression symptoms (beta = 4.43, p < .001). Taken together, toxicological matrices and self-reported cannabis use offer concurrent information in adolescents and young adults who regularly use cannabis. Plasma THCCOOH concentration uniquely predicted self-reported depression symptoms, indicating utility of toxicological cannabinoid concentration predicting clinical outcomes. Given the complexity of measuring cannabis use due to the plethora of available products and rise of new popular cannabinoids, use of toxicological results may offer new insights into clinical outcomes in those who frequently use cannabis.

The "poppy seed defense" - a claim that a positive opioid test result is due to ingestion of poppy seeds-is occasionally encountered in forensic toxicology. The matter has been thoroughly investigated in urine but is less researched in oral fluid. We therefore aimed to perform an experimental study to explore whether consumption of commercially available poppy seeds would lead to detection of opioids in oral fluid. Additionally, we aimed to relate our findings to routine cases. Ten volunteers consumed either five crispbreads containing a small amount of poppy seeds, or 30 grams of raw poppy seeds with a low opioid content (3.0 mg/kg morphine and 0.9 mg/kg codeine). Oral fluid samples were collected 0.5 and 2 hours after consumption. Additionally, a urine sample was collected 2 hours after consumption. Following ingestion of raw seeds, morphine was detected (estimated neat oral fluid concentrations 1.4-5.6 ng/mL) in all oral fluid samples 0.5 hours after consumption, and in one (2.4 ng/mL) of five oral fluid samples after 2 hours. Codeine was detected (0.8-1.1 ng/mL) in three of five oral fluid samples 0.5 hours after consumption, but in none after 2 hours. Following ingestion of crispbreads, morphine or codeine were not detected in oral fluid, but opioids/-glucuronides were detected in three of five urine samples. When comparing our results with routine cases, we found that 14% of routine cases had morphine concentrations in oral fluid samples lower or similar to those seen after ingestion of raw seeds in our experimental study. In conclusion, we found that consumption of raw seeds led to detection of opioids in oral fluid, but the detection window appeared to be short. Comparison with routine cases indicated that the poppy seed defense may be a challenge when interpreting oral fluid results, particularly when low cut-off levels are applied.