Journal of analytical toxicology最新文献

In 2018, Canada introduced roadside oral fluid (OF) screening devices, called Approved Drug Screening Equipment (ADSE), as an investigative tool in impaired driving investigations to detect tetrahydrocannabinol (THC), cocaine and/or methamphetamine in drivers. In this work, we compare the detection and concentration of THC in blood samples collected from suspected impaired drivers that tested positive at the roadside for THC on an ADSE. The two ADSEs that were utilized were the Dräger DrugTest® 5000 (DDT) and the Abbott SoToxa™ (SoToxa), both configured with a THC OF concentration cut-off concentration of 25 ng/mL. Blood samples were screened for cannabinoids using immunoassay and positive results were followed up by confirmation/quantitation of THC by ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS-MS). A total of 230 cases were available where a blood sample was collected from a suspected impaired driver subsequent to a positive THC screen result on an ADSE. The blood samples were taken an average of 1.4 hours (range = 9 minutes to 3.2 hours) after the ADSE test. THC was confirmed in 98% of blood samples with concentrations across all samples ranging from not detected (cut = off 0.5 ng/mL) to greater than 20 ng/mL. Further, 90% of the blood samples had a THC concentration of 2.0 ng/mL (the lower per se limit in Canada) or greater. A positive ADSE test of a suspected impaired driver may predict that the driver has a detectable level of THC in their blood, and there is a high likelihood that the THC blood concentration is 2.0 ng/mL or higher. Hence, ADSE may be a useful tool for law enforcement and aid in the development of grounds to believe that a driver is operating a conveyance with a THC concentration exceeding Canadian per se limits.

This article traces the origin of various charts and tables delineating the stages of alcohol influence in relation to the clinical signs and symptoms of drunkenness and a person's blood-alcohol concentration (BAC). In forensic science and legal medicine, the most widely used such table was created by Professor Kurt M. Dubowski (University of Oklahoma). The first version of the Dubowski alcohol table was published in 1957, and minor modifications appeared in various articles and book chapters until the final version was published in 2012. Seven stages of alcohol influence were identified including subclinical (sobriety), euphoria, excitement, confusion, stupor, alcoholic coma and death. The BAC causing death was initially reported as 0.45+ g%, although the latest version cited a mean and median BAC of 0.36 g% with a 90% range from 0.21 g% to 0.50 g%. An important feature of the Dubowski alcohol table was the overlapping ranges of BAC for each of the stages of alcohol influence. This was done to reflect variations in the physiological effects of ethanol on the nervous system between different individuals. Information gleaned from the Dubowski table is not intended to apply to any specific individual but more generally for a population of social drinkers, not regular heavy drinkers or alcoholics. Under real-world conditions, much will depend on a person's age, race, gender, pattern of drinking, habituation to alcohol and the development of central nervous tolerance. The impairment effects of ethanol also depend to some extent on whether observations are made on the rising or declining phase of the blood-alcohol curve (Mellanby effect). There will always be some individuals who do not exhibit the expected behavioral impairment effects of ethanol, such as regular heavy drinkers and those suffering from an alcohol use disorder.

Total morphine is an important urinary marker of heroin use but can also be present from prescriptions or poppy seed ingestion. In specimens with morphine concentrations consistent with poppy seed ingestion (<4,000 ng/mL), 6-acetylmorphine has served as an important marker of illicit drug use. However, as illicit fentanyl has become increasingly prevalent as a contaminant in the drug supply, fentanyl might be an alternative marker of illicit opioid use instead of or in combination with 6-acetylmorphine. The aim of this study was to quantify opiates, 6-acetylmorphine, fentanyl and fentanyl analogs in 504 morphine-positive (immunoassay 2,000 ng/mL cutoff) urine specimens from workplace drug testing. Almost half (43%) of morphine-positive specimens had morphine concentrations below 4,000 ng/mL, illustrating the need for markers to differentiate illicit drug use. In these specimens, fentanyl (22% co-positivity) was more prevalent than 6-acetylmorphine (12%). Co-positivity of 6-acetylmorphine and semi-synthetic opioids increased with morphine concentration, while fentanyl prevalence did not. In 110 fentanyl-positive specimens, the median norfentanyl concentration (1,520 ng/mL) was 9.6× higher than the median fentanyl concentration (159 ng/mL), illustrating the possibility of using norfentanyl as a urinary marker of fentanyl use. The only fentanyl analog identified was para-fluorofentanyl (n = 50), with results from most specimens consistent with para-fluorofentanyl contamination in illicit fentanyl. The results confirm the use of fentanyl by employees subject to workplace drug testing and highlight the potential of fentanyl and/or norfentanyl as important markers of illicit drug use.

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.

Exhaled breath (EB) contains various volatile organic compounds (VOCs) that can indicate specific biological or pathological processes in the body. Analytical techniques like gas chromatography-mass spectrometry (GC-MS) can be used to detect and measure these exhaled biomarkers. In this study, the objective was to develop a non-invasive method of EB sampling in animals that were awake, as well as to analyze EB for volatile biomarkers specific for chlorine exposure and/or diagnostic biomarkers for chlorine-induced acute lung injury (ALI). To achieve this, a custom-made sampling device was used to collect EB samples from 19 female Balb/c mice. EB was sampled both pre-exposure (serving as internal control) and 30 min after exposure to chlorine. EB was collected on thermal desorption tubes and subsequently analyzed for VOCs by GC-MS. The following day, the extent of airway injury was assessed in the animals by examining neutrophils in the bronchoalveolar lavage fluid. VOC analysis revealed alterations in the EB biomarker pattern post-chlorine exposure, with eight biomarkers displaying increased levels and six exhibiting decreased levels following exposure. Four chlorinated compounds: trichloromethane, chloroacetone, 1,1-dichloroacetone and dichloroacetonitrile, were increased in chlorine-exposed mice, suggesting their specificity as chlorine EB biomarkers. Furthermore, chlorine-exposed mice displayed a neutrophilic inflammatory response and body weight loss 24 h following exposure. In conclusion, all animals developed an airway inflammation characterized by neutrophil infiltration and a specific EB pattern that could be extracted after chlorine exposure. Monitoring EB samples can readily and non-invasively provide valuable information on biomarkers for diagnosis of chlorine-induced ALI, confirming chlorine exposures.

Due to the increase in the use of novel psychoactive substances (NPS) and their overall prevalence, it is important to have effective and reliable screening technologies to detect NPS in biological matrices. Enzyme-linked immunosorbent assays (ELISA) are among the most popular screening methods. To evaluate the effectiveness of ELISA for NPS detection, five subclasses of NPS (novel synthetic opioids, fentanyl analogs, stimulants, benzodiazepines and hallucinogens) were evaluated in whole blood for their cross-reactivity on commercially available ELISA kits. A variety of novel synthetic opioids were tested at concentrations of 1-80 ng/mL and 50-2000 ng/mL and demonstrated no cross-reactivity to a morphine ELISA plate at either concentration range. Fentanyl analogs were tested at concentrations ranging from 0.01 to 1 ng/mL and had cross-reactivities ranging from 8% to 178% on the fentanyl ELISA kit used. Both para-chloro fentanyl (178%) and acryl fentanyl (164%) showed cross-reactivities well above that of fentanyl. Novel stimulants were tested at concentrations of 0.5-40 ng/mL and 20-2,000 ng/mL. 4-Fluoroamphetamine was the only novel stimulant with cross-reactivity (3,354%) to the amphetamine ELISA plate. Novel benzodiazepines were tested at concentrations of 1-40 ng/mL on a benzodiazepine plate. Cross-reactivities ranged from 36.1% to 263%, with desalkylflurazepam having the highest cross-reactivity. Finally, novel hallucinogens were tested at concentrations of 0.5-10 ng/mL on a phencyclidine (PCP) ELISA plate, which produced no cross-reactivity and then with 10-1,000 ng/mL, which gave results from 56.6% to 151%. Both hydroxy-PCP (151%) and chloro-PCP (137%) showed cross-reactivities above that of PCP. This research has demonstrated the utility of using ELISA-based screening for novel benzodiazepines, hallucinogens and for fentanyl analogs; however, there is limited application and risk of false-negative results for the other drug classes due to low or non-existent cross-reactivities.