Journal of analytical toxicology最新文献

Recently, tetrahydrocannabinol (THC) isomers and other semi-synthetic cannabinoids have been introduced into the consumer market as alternatives to botanical cannabis. To assess the prevalence of these potential new analytical targets, a liquid chromatography-tandem mass spectrometry confirmation method was developed for the quantitation of seven cannabinoid metabolites and the qualitative identification of four others in urine. The validated method was applied to authentic urine specimens that screened positive by immunoassay (50 ng/mL cutoff; n=1300). The most commonly observed analytes were 11-nor-9-carboxy-Δ8- and Δ9-THC (Δ8- and Δ9-THCCOOH), with the combination of the two seen as the most prominent analyte combination found. In addition to these metabolites, Δ1°-THCCOOH was observed in 77 specimens. This is the first study to report Δ1°-THCCOOH in authentic urine specimens, with this analyte always appearing in combination with Δ9-THCCOOH. Cross-reactivity studies were performed for (6aR,9R)-Δ1°-THCCOOH using the Beckman Coulter Emit® II Plus Cannabinoid immunoassay and demonstrated cross reactivity equivalent to the Δ9-THCCOOH cutoff, providing added confidence in the reported prevalence and detection patterns. Additionally, 11-nor-9(R)-carboxy-hexahydrocannabinol (9(R)-HHCCOOH) was the most abundant stereoisomer (n=12) in specimens containing HHC metabolites alone (n=14). This is in contrast to 9(S)-HHCCOOH, which was the predominant stereoisomer in specimens containing Δ8- and/or Δ9-THCCOOH. Although HHC and Δ1°-THC metabolites are emerging toxicology findings, based on these specimens collected between April 2022 and May 2024, an analytical panel containing Δ8- and Δ9-THCCOOH appears to be sufficient for revealing cannabinoid exposure within workplace monitoring and deterrence programs.

Novel psychoactive substances (NPS) continue to emerge in the marketplace and are often found as substances in traditional illicit drug materials, and users are often unaware of the presence of other drugs. The proper identification and confirmation of the exposure to a drug is made possible when a biological specimen is collected and tested. Sweat is an alternative biological matrix of great interest for clinical, and forensic analysis. One of the reasons is attributed to its expanded drug detection window, enabling a greater monitoring capacity, and provision of information on prospective drug use. However, the concentrations of drugs in sweat samples are often low, which requires highly sensitive and selective methods. Disposable pipette tips extraction (DPX) is a new miniaturized solid phase extraction technique capable of efficiently extracting analytes from biological specimens, providing high recoveries, and requiring minimized solvent use. This study describes the development and optimization of two methods for the extraction of basic and neutral psychoactive substances from sweat samples using GC-MS and Design of Experiments (DoE). The following extraction parameters were optimized by DoE techniques: sample volume, elution solvent volume, washing solvent volume, sample aspiration time, elution solvent aspiration time, and number of cycles performed, including the elution step. It was possible to design a simple extraction protocol that provided optimized recoveries for both basic and neutral compounds. The sum of analyte areas increased at a rate of 54.7% for compounds of basic character and 39.2% for compounds of neutral character. Therefore, our results were satisfactory, demonstrating that DPX can be successfully used for extracting the target drugs from sweat samples.

As cocaine (COC) is not only incorporated into hair via blood following ingestion but also by external contamination, hair samples are commonly tested for COC metabolites to prove ingestion. However, COC metabolites can also be present as degradation products in typical street COC samples. The present study investigates minor hydroxycocaine (OH-COC) metabolites p- and m-OH-COC together with p- and m-hydroxybenzoylecgonine (OH-BE) in seized COC (n = 200) and hair samples from routine case work (n = 2389). Analytical results of hair samples were interpreted using an established decision model for the differentiation between actual use and external contamination using metabolic ratios (metabolite to COC). They were further examined concerning background of request, hair color, body site of sample collection, sex, and metabolic ratios of the main metabolites [benzoylecgonine (BE), norcocaine (NC), and cocaethylene (CE)]. All seized COC samples were positive for p- and m-OH-COC with a maximum percentage of 0.025% and 0.052%, respectively; p- and m-OH-BE were detected in 55% and 56% of samples with a maximum percentage of 0.044% and 0.024%, respectively. Analytical results of 424 hair samples (17.7%) were interpreted as being predominantly from contamination; the majority of these samples were from traffic medicine cases (83.7%). Metabolic ratios of minor OH-COC metabolites were significantly higher in hair samples interpreted as originating from use than in samples interpreted as caused by contamination. Metabolic ratios for OH-COCs were significantly higher in forensic cases compared to abstinence controls and also in black hair compared to blond/gray hair. However, this was not the case for OH-BE metabolic ratios. No statistical difference was observed with regard to the donor's sex. OH-COC metabolic ratios increased significantly with increasing ratios of NC and CE to COC, respectively. The study demonstrates that OH-COC metabolites (including thresholds for their metabolic ratios) must be used for a reliable interpretation of positive COC results in hair samples.

Accidental overdose cases continue to rise due to the opioid epidemic in the USA, namely, the widespread availability and use of fentanyl. Medical examiners and coroners across the country have been subsequently burdened, and with limited resources, some seek alternative triaging processes to identify overdoses. Point-of-care urine dipstick testing at autopsy is one such idea that may be used in various ways to instigate or negate the need for an autopsy or regular forensic toxicology laboratory testing. This study investigated the frequency and estimated quantitative fentanyl and norfentanyl concentrations in the postmortem urine of fentanyl-related accidental overdose deaths, as well as the effectiveness of commercially available point-of-care urine dipstick tests based on such concentrations. A total of 1550 fentanyl-related accidental overdose cases, where both the postmortem peripheral femoral blood and urine were tested, were reviewed. Of these, using sensitive liquid chromatography-tandem mass spectrometry (LC-MS-MS) laboratory testing, 82 cases (5%) had a positive fentanyl or norfentanyl detection in the blood, while fentanyl or norfentanyl remained undetected in the urine. Furthermore, a comparison of commercially available urine dipstick test cut-offs and authentic casework with estimated urine concentrations revealed that at a fentanyl/norfentanyl cut-off level of 5 ng/mL, 19% of these fentanyl-related accidental overdoses would result in a false negative, 24% at 10 ng/mL, 25% at 20 ng/mL, 51% at 50 ng/mL, and 61% at 100 ng/mL. The study found that the use of urine dipstick tests, as a decision-maker for the initiation of further comprehensive routine toxicology laboratory testing, or to support cause and manner of death determination, leads to both false-positive and false-negative predictions in fentanyl accidental overdoses.

In recent years, the use of 2-benzylbenzimidazole opioids ('nitazenes') has increased with them becoming one of the most prominent synthetic opioid subclasses of novel psychoactive substances. With the increased prevalence, there is also a concern of the dangers to public health with the use of nitazenes due to their high potency especially with polypharmacy. To aid in the detection of such compounds, it is important that forensic toxicology laboratories maintain up-to-date compound libraries for drug screening methods and that sensitive analytical instrumentation is available to detect the low blood/plasma concentrations of more potent drugs. This includes not only the compounds themselves but also potential metabolites and/or degradation products. Metonitazene is a 'nitro-nitazene' with a nitro group at position 5 of the benzimidazole ring. As a nitro-nitazene, there is a potential for bacterial degradation of metonitazene to 5-aminometonitazene, as occurs with nitro-benzodiazepines. In this study, we provide evidence from a postmortem (PM) case of degradation of metonitazene in unpreserved PM blood using liquid chromatography-triple quadrupole mass spectrometry (LC-QQQ-MS), and putative identification of the degradation/metabolic products 5-aminometonitazene and 5-acetamidometonitazene by liquid chromatography-quadrupole time-of-flight mass spectrometry. The results from LC-QQQ-MS analysis indicated that there did not appear to be such degradation in preserved (fluoride/oxalate) blood. These results suggest that nitro-nitazenes may be subject to similar in vitro stability/degradation issues as nitro-benzodiazepines. These breakdown products should be added to instrument libraries to aid in the detection of the use of nitro-nitazenes, and nitro-nitazenes should be quantified in preserved blood samples where available.

Recently, etomidate has been widely used as an alternative in illicit drug market. It is usually added to regular cigarette tobacco (commonly known as "cigarette powder") or mixed in e-cigarette oil sold through the Internet, retail stores, or entertainment outlets and other channels. An ultra-high performance liquid chromatography tandem mass spectrometry method was developed to quantify etomidate and etomidate acid in human blood and urine. The limit of detection (LOD) of etomidate and etomidate acid in blood is 0.5  and 2 ng/mL, respectively, and the lower limit of quantification (LLOQ) is 1  and 5 ng/mL, respectively. The LOD of etomidate and etomidate acid in urine is 1 and 2 ng/mL, respectively, and the LLOQ is 2  and 5 ng/mL, respectively. The precision, accuracy, recoveries, and matrix effects of etomidate and etomidate acid determinations in blood and urine met the requirements for methodological validation. The method was successfully applied to the identification and quantification of etomidate and etomidate acid in blood and urine of 62 forensic cases. The concentration of etomidate ranged from 1.52 to 8.41 ng/mL (positive cases, n = 5) and the concentration of etomidate acid ranged from 2.76 to 112 ng/mL (positive cases, n = 5) in blood. The concentrations of etomidate and etomidate acid in urine samples were 2.64-79,300 ng/mL (positive cases, n = 59) and 6.11-518,000 ng/mL (positive cases, n = 60), respectively. Therefore, the concentration of etomidate in blood and urine is mostly higher than that of etomidate.

With some exceptions, California Assembly Bill 2188 will preclude the use of ∆9-tetrahydrocannabinol-9-carboxylic acid (Δ9-THC-COOH) as a marker of cannabis use in urinary workplace drug testing. The bill allows for the use of psychoactive cannabis markers, which include Δ9-tetrahydrocannabinol (Δ9-THC) and the metabolite 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-Δ9-THC). Both analytes are present in urine mainly as conjugated metabolites and will require hydrolysis prior to analysis, but very little is known about expected concentrations in urine. The aim of this study was to report the concentrations from two large datasets comprising 1411 workplace drug-testing urine specimens that tested positive by immunoassay (50 ng/mL cutoff) and discuss strategies for using 11-OH-Δ9-THC and/or Δ9-THC to detect cannabis use. Median 11-OH-Δ9-THC and Δ9-THC concentrations were 28%-35% and 1.1%-1.6% of those of Δ9-THC-COOH, respectively, and correlations between the analytes were observed. To avoid the risk of positives from passive exposure, laboratories could use a cutoff with equivalent sensitivity to cannabis exposure. A 5 ng/mL cutoff for 11-OH-Δ9-THC showed 92% agreement with a 15 ng/mL cutoff for Δ9-THC-COOH, with only 0.9% of specimens being positive only for 11-OH-Δ9-THC. It was not possible to propose an estimated cutoff for Δ9-THC, due to the constraints of the limit of detection used in this study.

Novel benzodiazepine (NBz) detections in Victorian coronial cases started early in 2018 and have continued to increase in number and type up to December 2022. The 11 different NBz detections included etizolam (n = 82), flualprazolam (n = 43), clonazolam or 8-aminoclonazolam (n = 30), bromazolam (n = 15), clobromazolam (n = 13), phenazepam (n = 13), flubromazolam (n = 12), flubromazepam (n = 8), desalkylflurazepam (n = 6), diclazepam (n = 2), and estazolam (n = 1). The pattern of detections varied over the 5-year period, with different compounds appearing over different time frames. The most recent NBz to appear were bromazolam, clobromazolam, flubromazepam, and phenazepam, whereas etizolam had been seen regularly in case work since 2018. Of the total 133 deaths, 95 were considered drug-related deaths by forensic pathologists with at least one additional CNS depressant also present capable of contributing to death. All deaths involved other (non-benzodiazepine) CNS active drugs, although many involved multiple NBz, with five or more different benzodiazepines detected in eight cases.

The designer benzodiazepine bromazolam is increasingly encountered in forensic casework, including impaired driving investigations. A series of suspected impaired driving cases that tested positive for bromazolam are described herein along with information about driving performance, driver appearance, and observed behavior. Bromazolam was indicated in casework either through screening by liquid chromatography-time of flight mass spectrometry (LC-TOF-MS) and/or a positive benzodiazepine immunoassay screen. Blood samples were forwarded for quantitative confirmatory analysis using a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method with a reporting limit of 2.0 ng/mL. Bromazolam was reported in 98 impaired driving cases from samples reported between January 2021 and December 2023, with the earliest detection from September 2020. Mean and median blood concentrations were 125 ± 145 and 84 ng/mL respectively, with a range of 4.2-990 ng/mL. Additional positive findings were reported in almost all cases, with the highest result (990 ng/mL) being the only case in which bromazolam was the only finding. Fentanyl was the most frequent drug found in combination with bromazolam. Driving behaviors reported in these cases included erratic driving, errors in Standardized Field Sobriety Tests, and symptoms consistent with central nervous system depressants, including slurred speech, incoordination, and lethargic behavior. Based on its prevalence and demonstrated impairing effects, bromazolam should be included in the scope of impaired driving testing as long as it continues to be prevalent in the drug supply.