Drug Testing and Analysis最新文献

Community-based drug checking services are challenged in their ability to reliably detect low concentration adulterants that are increasingly present in the illicit drug supply. Spectral signatures from commonly used field instruments such as infrared spectrometers require careful analysis to identify characteristic features in a complex mixture. In this study, we train neural network models for the detection of bromazolam and para-fluorofentanyl, using infrared absorption data collected at a point-of-care drug checking service. The neural network models classified the two components with an F1-score of 0.88 for bromazolam and 0.89 for para-fluorofentanyl. In comparison, a random forest model optimized using the same data set had an F1-score of 0.66 for bromazolam and 0.76 for para-fluorofentanyl. This demonstrates that neutral networks are excellent candidates for such complex drug detection applications and outperform other machine learning-based approaches.

A novel patent-based effervescent tablet was developed and evaluated as a selective filter for reducing hazardous chemical compounds in hookah smoke. The study combined gas chromatography-mass spectrometry (GC-MS) and atomic absorption spectroscopy (AAS) to identify and quantify major toxicants. Hookah smoke was trapped using cellulose nanofiber-based solvent chambers and latex puff chambers, followed by analysis of volatile organic compounds (nicotine, propylene oxide, formaldehyde, crotonaldehyde, acrolein, acetaldehyde, 1,3-butadiene, benzopyrene, pyridine, phenol, benzene) and potentially toxic trace elements (PTEs) such as lead, mercury, cadmium, and chromium. Detection limits (LODs) ranged from 0.003 to 0.04 mg/g, with relative standard deviations (RSDs) below 13%. The effervescent tablet reduced > 81% of hazardous compounds while selectively lowering nicotine and flavor by approximately 15%, maintaining user acceptability. Compared with cigarette smoke, unfiltered hookah smoke contained significantly higher levels of aldehydes and polycyclic aromatic hydrocarbons, whereas filtered hookah smoke showed markedly lower contaminant concentrations than both cigarette and e-cigarette smoke. The proposed method demonstrates innovation by integrating a user-friendly, selective effervescent tablet with high recovery (92%-102%) and accuracy, offering a practical strategy for harm reduction in hookah smoking.

Chronic exposure to pesticides can cause carcinogenic, reproductive, neurological, and endocrine-disrupting effects. Hair analysis is a valuable biomonitoring tool to assess human exposure to pesticides. We determined the presence of pesticides, their metabolites, and other environmental pollutants in the hair of children in an agricultural area of Paraguay. We analyzed 152 pesticides and environmental chemicals in hair samples from 51 children (2-14 years, mean ± SD = 8.5 ± 3.3 years) living in Colonia San Juan, a rural community in Paraguay. The locality is surrounded by soybean crops, and the community engages primarily in family farming. Eighty of the 152 compounds (52.6%) were detected. Each child's sample contained an average of 55 ± 3.7 compounds (range 48-65), including organophosphates, pyrethroids, neonicotinoids, fungicides, herbicides, and endocrine disruptors such as bisphenol A and bisphenol S. Thirty-seven compounds were present in all samples. Children in this rural community are simultaneously exposed to numerous pesticides and pollutants, highlighting the urgent need for stricter environmental protections and preventive health measures.

In this study, we assess the feasibility of wastewater sampling from manholes as a potential monitoring tool for performance and image-enhancing drugs (PIEDs) at local gyms and general sports centers in Denmark. Wastewater samples from two gyms and two sports centers were analyzed using two LC-MS-based analytical methods (UPLC-MS/MS and UPLC-TOF-MS) to detect the presence of PIEDs. Samples were collected at 3-h intervals during the opening hours on three selected days of the week for each location. The study showed the presence of anabolic agents such as oxandrolone, stanozolol, and ostarine in wastewater sampled from the gyms. All three compounds are class C drugs in the United States, and likewise, illegal to sell and possess in Denmark. Other PIEDs, such as aromatase inhibitors and psychoactive drugs, were detected in several samples from both gyms and sports centers. However, gyms showed a higher occurrence of PIEDs, whereas general sports centers showed a lower occurrence. Although it cannot be used as a traditional prevalence measure, wastewater sampling from manholes is a useful tool for studying the occurrence of PIEDs among recreational athletes at specific locations or events. Wastewater analysis may be used as an easy and cost-effective tool to complement both preventive and control measures, such as information campaigns, surveys, or personal testing. However, not all locations are suitable for manhole sampling, and it is necessary to consider the legal, ethical, and practical aspects before using wastewater analysis to monitor communities or specific populations.

Methyldienolone, a synthetic anabolic androgenic steroid (AAS), has been banned in sports by the World Anti-Doping Agency (WADA) because of its performance-enhancing properties. This study aimed to investigate the main metabolites using in vitro incubation with human liver microsomes (HLM) and to detect them through liquid chromatography-high-resolution mass spectrometry (LC-HRMS) for doping control purposes. A total of six groups of Phase I metabolites, including 17-epimerization, hydroxylation, C3-keto reduction, 18-nor modifications, reduction, and demethylation, as well as five different Phase II metabolites, such as glucuronide conjugates, were characterized, indicating extensive metabolism by HLM. Structural characterization of these metabolites was improved through derivatization with methoxylamine and hydroxylamine, which enabled their detection with higher sensitivity by LC-HRMS. These novel metabolites provide new insights into the metabolism of methyldienolone and may contribute to antidoping analysis. The synthesis of reference materials is necessary to confirm the structure of the proposed metabolites in the future.

In recent years, a scenario involving milk contamination by biotransformation products of the veterinary drug Emidonol has received widespread publicity. Emidonol is intended for use in cattle under pathological conditions accompanied by hypoxia. The drug dissociates into two antihypoxants-meldonium, a metabolic modulator prohibited in sports, and emoxypine, which also has antioxidant properties. A small-scale pilot study involved three volunteers consuming a single 900-mL dose of unpasteurized cow's milk collected on the last (15th) day of treatment with the drug. The mean estimated urinary concentration of emoxypine peaked between 7- and 8.5-h postadministration (1360 ± 240 ng/mL), elimination time being approximately 50-54 h. The mean estimated urinary concentration of meldonium peaked between 5.8- and 9.0-h postadministration and was 322 ± 68 ng/mL, elimination time being approximately 35-45 h. The simultaneous presence of emoxypine and meldonium in urine samples may be indicative of the consumption of Emidonol-contaminated milk, which may facilitate the identification of cases of unintended doping in sport.

Already in the 1960s, the anabolic properties of Trestolone (7α-methyl-19-nortestosterone, MENT) were investigated in the context of cancer research, and MENT was found to be 10 times more potent regarding its anabolic properties compared to testosterone. The human metabolism of MENT was only investigated once in an antidoping context, and three urinary metabolites were identified, corroborating earlier findings from in vitro and animal experiments. Based on these metabolites, no doping control sample was reported to contain MENT or its metabolites in the last two decades albeit MENT is readily available via online distributors. One reason for the lack of adverse analytical findings in doping controls could be analytical challenges originating from the chromatographic properties of MENT and its urinary metabolites. Therefore, the human metabolism of MENT was reinvestigated employing an excretion study with deuterated MENT and metabolite detection based on hydrogen isotope ratio mass spectrometry in combination with high accuracy/high resolution mass spectrometry. Considering unconjugated, glucuronidated, and sulfated metabolites, 50 potential candidates were detected. In order to identify those metabolites suitable for sports drug testing, three volunteers administered a single oral dose of nondeuterated MENT, and all postadministration samples were investigated using triple quadrupole mass spectrometry-based determinations routinely employed in doping controls. From the 50 metabolites detected, two showed promising results with respect to their detection windows and suitability under routine measurement conditions. The specificity of the novel metabolites was ensured by the reanalysis of 200 routine doping control samples demonstrating the absence of potential coeluting compounds.

This paper describes the detection and longitudinal monitoring of cyclosporine in plasma and urine after subconjunctival implant administration in a horse. Sensitive liquid chromatography tandem mass spectroscopy (LC-MS/MS) methods for detecting cyclosporine in horse plasma and urine have been developed and validated, with estimated limits of detection down to 1 pg/mL in both matrices. The developed methods enabled longitudinal monitoring of cyclosporine levels in blood and urine samples collected over 6 months from a horse that had received an ocular cyclosporine implant.

Recreational use of nitrous oxide (laughing gas, N₂O) is becoming increasingly common and abuse is often seen in relation to driving, posing significant traffic-safety concerns. Only a few studies exist on blood concentrations of N₂O and its detectability over time after use. In this study, 11 volunteers received controlled administration of 50% N₂O for 10 min, after which blood samples were drawn and analyzed for N₂O by headspace-gas chromatography-mass spectrometry (HS-GC-MS). Pharmacokinetic modelling indicated that elimination of N₂O can best be described by a two-compartment model with half-lives of 2.4 and 31 min. Although both the pharmacological effect and intoxication typically disappear within minutes after intake, N₂O remained detectable in blood for an average of 62 min at a cutoff of 0.2 mL/L and 132 min at a cutoff of 0.05 mL/L.