A case of intoxication with a new cathinone derivative α-PiHP – A presentation of concentrations in biological specimens

α-Pyrrolidinohexanophenone (α-PHP) vs. α-pyrrolidinoisohexanophenone (α-PiHP): A toxicological investigation about plasma concentrations and behavior in forensic routine cases

New psychoactive substances (NPS), like pyrrolidinophenones, are still very present on the illegal drug market. The presented study reports on two members of this substance group, α-pyrrolidinohexanophenone (α-PHP) and α-pyrrolidinoisohexanophenone (α-PiHP), which occurred in forensic routine cases in the last 6 years. α-PHP could be detected predominantly by a validated liquid chromatography-tandem mass spectrometry (LC-MS-MS) method in 33 authentic human plasma samples and α-PiHP in 8. α-PHP concentrations ranged from ca. 0.75 to 128 µg/L (mean: 23.2, median: 16.3) and α-PiHP concentrations from 7.33 to 118 µg/L (mean: 44.7, median: 33.7, quantified via α-PHP). Individuals were predominantly male and middle aged. As different studies have shown, some pyrrolidinophenones are able to cause aggressive behavior. Therefore, we set out to investigate the relation of α-PHP and α-PiHP plasma concentrations and the behavior of the consumers, reported by police and medical experts. Part of the subjects showed aggressive behavior, including agitation and restlessness. Lethargic and unremarkable behavior might be explained by co-consumption of other drugs, such as opiates/opioids, benzodiazepines, pregabalin or alcohol as well as by drug tolerance and subacute effects of stimulants. Multi-drug use could be detected in all cases; also stimulating substances and multiple different pyrrolidinophenones were determined. Nevertheless, users of α-PHP and α-PiHP showed a tendency to act aggressively, possibly triggered by a high selectivity for dopamine transporter inhibition. In accordance, committed offenses were often violent crimes. This might be considered in terms of toxicological assessment of criminal responsibility and driving ability.

3-CMC, 4-CMC, and 4-BMC Human Metabolic Profiling: New Major Pathways to Document Consumption of Methcathinone Analogues?

Synthetic cathinones represent one of the largest and most abused new psychoactive substance classes, and have been involved in numerous intoxications and fatalities worldwide. Methcathinone analogues like 3-methylmethcathinone (3-MMC), 3-chloromethcathinone (3-CMC), and 4-CMC currently constitute most of synthetic cathinone seizures in Europe. Documenting their consumption in clinical/forensic casework is therefore essential to tackle this trend. Targeting metabolite markers is a go-to to document consumption in analytical toxicology, and metabolite profiling is crucial to support investigations. We sought to identify 3-CMC, 4-CMC, and 4-bromomethcathinone (4-BMC) human metabolites. The substances were incubated with human hepatocytes; incubates were screened by liquid chromatography-high-resolution tandem mass spectrometry and data were mined with Compound Discoverer (Themo Scientific). 3-CMC-positive blood, urine, and oral fluid and 4-CMC-positive urine and saliva from clinical/forensic casework were analyzed. Analyses were supported by metabolite predictions with GLORYx freeware. Twelve, ten, and ten metabolites were identified for 3-CMC, 4-CMC, and 4-BMC, respectively, with similar transformations occurring for the three cathinones. Major reactions included ketoreduction and N-demethylation. Surprisingly, predominant metabolites were produced by combination of N-demethylation and ω-carboxylation (main metabolite in 3-CMC-positive urine), and combination of β-ketoreduction, oxidative deamination, and O-glucuronidation (main metabolite in 4-CMC-positive urine). These latter metabolites were detected in negative-ionization mode only and their non-conjugated form was not detected after glucuronide hydrolysis; this metabolic pathway was never reported for any methcathinone analogue susceptible to undergo the same transformations. These results support the need for comprehensive screening strategies in metabolite identification studies, to avoid overlooking significant metabolites and major markers of consumption.

α-Pyrrolidinohexanophenone (α-PHP) and α-Pyrrolidinoisohexanophenone (α-PiHP): A Review

New Psychoactive Substances are currently a serious and growing problem affecting public health worldwide. By 2022, 1184 of these substances had been identified over a period of 16 years. Within these, α-pyrrolidinohexanophenone (α-PHP) and α-pyrrolidinoisohexanophenone (α-PiHP) have emerged, two synthetic cathinones from the pyrovalerone derivates subgroup that are positional isomers of each other. Alpha-PHP appeared on the Japanese illicit drug market in 2014 and, two years later, α-PiHP was identified for the first time in China. They were placed in schedule II on the list of Psychotropic Substances under International Control in 2020 and in March 2023, respectively. Both cathinones have no therapeutic potential for medical use and therefore are abused for recreational habits, which can lead to fatalities. The most frequent adverse effects reported are cardiac, psychiatric, and neurologic, and fatal intoxications have already been described. In Portugal, their consumption and consequent seizures are more prevalent on the archipelagos, which has been aggravating the health situation. In conclusion, these types of substances are a challenge for forensic toxicology since they are easily synthesized, modified, and placed on the market. Therefore, more studies to develop analytical methods to detect them and more comprehensive legislation should be applied. Thus, this review aimed to address the legislative, physicochemical, toxicological, and analytical aspects of both substances.

Interpretative problems due to the presence of chloromethcathinone isomers in the biological material from postmortem cases

While many new psychoactive substances often disappear from the drug market rather quickly, some, such as synthetic cathinones (SCs), still remain due to their popularity among users. The current knowledge of SC concentrations in blood samples is based mainly on the published case reports of intoxications or fatalities caused by SC intake. The aim of the present study was to present and interpret the obtained toxicological analysis results of these cases, in which it was possible to determine or detect the presence of one of the isomers of chloromethcathinone (CMC) along with its intake biomarker-dihydro-CMC. These cases include 27 deaths reported at the Department of Forensic Medicine in Kraków in 2016-2022. CMC constitutes a major toxicological opinion challenge, in terms of toxicological evaluation of poisonings. As presented in this paper, a significant problem is its stability in the biological material and practices in the reporting of the obtained data. It is therefore important to monitor potential intake biomarkers that may show greater stability in the biological material than the parent drug. In the case of CMC isomers, the good biomarker of intake is the dihydro-CMC metabolite, which was detected in the blood sample in every case presented, even with the absence of the parent substance. Interpretation of the results obtained for CMC in terms of assessing their toxicity and possible cause of death is difficult. However, it should be taken into account that in cases of new psychoactive substance poisoning, an in-depth risk assessment is mandatory and the opinion of the unpredictability of the effects is taken as a principle.

Metabolism of the Synthetic Cathinone Alpha-Pyrrolidinoisohexanophenone in Humans Using UHPLC--MS-QToF

Alpha-pyrrolidinoisohexanophenone (α-PHiP/α-PiHP) is a synthetic drug structurally related to cathine, a natural psychoactive alkaloid, isolated from Khat plant. The α-PiHP is a structural isomer of α-PHP, and both α-PHP and α-PiHP could be considered an analog of α-PVP, a Schedule I drug under the Convention on Psychotropic Substances by the United Nations. This α-pyrrolidinophenone was first reported to European Monitoring of Drug and Drug Addiction by Slovenia in December 2016. In Hungary, it was initially reported in August 2016, and until 2021, it had been detected in seizures only twice and never been identified in biological samples. However, in 2021, its consumption became prevalent in Hungary. This study aims to investigate the α-PiHP metabolites by performing in vitro and in vivo metabolite identification studies of human liver microsome (pHLM), S9 fraction (pS9) and urine samples (from control and users), using liquid chromatography in conjunction with high-resolution mass spectrometry. Ten in vivo urinary metabolites of α-PiHP were tentatively identified and confirmed by in vitro metabolites detected in pHLM and pS9 samples. Among the eight Phase I and the two Phase II metabolites, five were more abundant in urine than the parent compound. The two major metabolites via reduction of the keto moiety (M01) and via oxidation of the pyrrolidine ring combined with aliphatic hydroxylation and keto reduction (M06) were identified. The metabolites via the combination of keto reduction and aliphatic hydroxylation (M04), via ring-opening followed by carboxylation (M09) and via glucuronidation of the keto reduced metabolite (M07) were also dominant. The minor metabolites were one Phase II metabolite (M08), two metabolites via aliphatic hydroxylation (M02 and M03), one metabolite via the combination of keto reduction and oxidation of the pyrrolidine ring (M05) and one metabolite via oxidation of the pyrrolidine ring (M10).

Comparison of locomotor stimulant and drug discrimination effects of four synthetic cathinones to commonly abused psychostimulants

BACKGROUND

The underground market is constantly flooded with newer synthetic as alternatives to the older cathinones. Drug Enforcement Administration (DEA) has identified four cathinone compounds of particular concern: 3,4-methylenedioxy-alpha-pyrrolidinohexanophenone (3,4-MD-α-PHP), 4-chloro-α-pyrrolidinopropiophenone (4-Cl-α-PPP), alpha-pyrrolidinoisohexiophenone (α-PiHP) and 4-chloro-pentedrone (4-Cl-pentedrone).

AIMS

The current study aimed to evaluate the behavioral pharmacology of four synthetic cathinones.

METHODS

3,4-MD-α-PHP, 4-Cl-α-PPP, α-PiHP, and 4-CPD were tested for locomotor activity in mice and in a drug discrimination assay with rats trained to discriminate either methamphetamine or cocaine.

RESULTS

Locomotor stimulant effects of 3,4-MD-α-PHP ((effective dose) ED₅₀ = 1.98 mg/kg), α-PiHP (ED₅₀ = 2.46 mg/kg), and 4-Cl-α-PPP (ED₅₀ = 7.18 mg/kg) were observed within 10 min following injection and lasted from 2 to 3.5 h. The stimulant action of 4-CPD (ED₅₀ = 17.24 mg/kg) was delayed, occurring 40-70 min following injection. The maximal motor stimulant actions of 3,4-MD-α-PHP and α-PiHP 1 were equivalent to that of cocaine and methamphetamine, whereas 4-CPD (50% of cocaine) and 4-Cl-α-PPP (73% of cocaine) were less efficacious. All of the test compounds fully substituted for the discriminative stimulus effects of cocaine, 3,4-MD-α-PHP (ED₅₀ = 2.28 mg/kg), α-PiHP (ED₅₀ = 3.84 mg/kg), and 4-Cl-α-PPP (ED₅₀ = 15.56 mg/kg). Only 3,4-MD-α-PHP (ED₅₀ = 1.65 mg/kg), α-PiHP (ED₅₀ = 1.87 mg/kg), and 4-Cl-α-PPP (ED₅₀ = 9.79 mg/kg) fully substituted for the discriminative stimulus effects of methamphetamine. 4-Cl-pentedrone caused 55-70% methamphetamine-appropriate responding at doses that also suppressed responding and produced convulsions.

CONCLUSIONS

These data indicate that 3,4-MD-α-PHP, α-PiHP, and 4-Cl-α-PPP have a potential for abuse similar to that of methamphetamine and cocaine. In contrast, 4-Cl-pentedrone may not be popular for recreational use due to its convulsant effects.

Synthesis of emerging cathinones and validation of a SPE GC-MS method for their simultaneous quantification in blood

Over the past 15 years, synthetic cathinones have emerged as an important class of new psychoactive substances (NPS) worldwide. The proliferation of these psychostimulants and their sought-after effects among recreational drug users pose a serious threat to public health and enormous challenges to forensic laboratories. For forensic institutions, it is essential to be one step ahead of covert laboratories, foreseeing the structural changes possible to introduce in the core skeleton of cathinones while maintaining their stimulating activity. In this manner, it is feasible to equip themselves with standards of possible new cathinones and validated analytical methods for their qualitative and quantitative detection. Therefore, the aim of the work herein described was to synthesize emerging cathinones based on the evolving patterns in the illicit drug market, and to develop an analytical method for their accurate determination in forensic situations. Five so far unreported cathinones [4'-methyl-N-dimethylbuphedrone (4-MDMB), 4'-methyl-N-ethylbuphedrone (4-MNEB), 4'-methyl-N-dimethylpentedrone (4-MDMP), 4'-methyl-N-dimethylhexedrone (4-MDMH), and 4'-methyl-N-diethylbuphedrone (4-MDEB)] and a sixth one, 4'-methyl-N-ethylpentedrone, already reported to EMCDDA and also known as 4-MEAP, were synthesized and fully characterized by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). An analytical method for the simultaneous quantification of these cathinones in blood, using solid phase extraction (SPE) combined with gas chromatography-mass spectrometry (GC-MS) was developed and validated. The results prove that this methodology is selective, linear, precise, and accurate. For all target cathinones, the extraction efficiency was higher than 73%, linearity was observed in the range of 10 (lower limit of quantification, LLOQ) to 800 ng/mL, with coefficients of determination higher than 0.99, and the limits of detection (LODs) were 5 ng/mL for all target cathinones. The stability of these cathinones in blood matrices is dependent on the storage conditions; 4-MNEB is the most stable compound and 4-MDMH is the least stable compound. The low limits obtained allow the detection of the compounds in situations where they are involved, even if present at low concentrations.

A review of synthetic cathinones emerging in recent years (2019-2022)

Purpose

The emergence of novel psychoactive substances (NPS) has been being a continuous and evolving problem for more than a decade. Every year, dozens of new, previously unknown drugs appear on the illegal market, posing a significant threat to the health and lives of their users. Synthetic cathinones are one of the most numerous and widespread groups among NPS. The purpose of this work was to identify and summarize available data on newly emerging cathinones in very recent years.

Methods

Various online databases such as PubMed, Google Scholar, but also databases of government agencies including those involved in early warning systems, were used in search of reports on the identification of newly emerging synthetic cathinones. In addition, threads on various forums created by users of these drugs were searched for reports on the effects of these new substances.

Results

We have identified 29 synthetic cathinones that have been detected for the first time from early 2019 to mid-2022. We described their structures, known intoxication symptoms, detected concentrations in biological material in poisoning cases, as well as the countries and dates of their first appearance. Due to the lack of studies on the properties of the novel compounds, we compared data on the pharmacological profiles of the better-known synthetic cathinones with available information on the newly emerged ones. Some of these new agents already posed a threat, as the first cases of poisonings, including fatal ones, have been reported.

Conclusions

Most of the newly developed synthetic cathinones can be seen as analogs and replacements for once-popular compounds that have been declining in popularity as a result of legislative efforts. Although it appears that some of the newly emerging cathinones are not widely used, they may become more popular in the future and could become a significant threat to health and life. Therefore, it is important to continue developing early warning systems and identifying new compounds so that their widespread can be prevented.

Fatal cases involving new psychoactive substances and trends in analytical techniques

New psychoactive substances (NPS) are an emerging public health issue and deaths are commonly associated with polydrug abuse. Moreover, the number of new substances available is constantly increasing, causing intoxications in low doses, characteristics that impose to toxicology and forensic laboratories to keep routine methods up to date, with high detectability and constantly acquiring new analytical standards. Likewise, NPS metabolites and respective elimination pathways are usually unknown, making it difficult the detection and confirmation of the drug involved in the fatal case in an analytical routine. A literature search was performed on PubMed, Scopus and Web of Science databases for papers related to chromatographic analyses from fatal cases related to NPS use published from 2016 to 2021. A total of 96 papers were retrieved and reviewed in this study. Opioids, synthetic cathinones, phenethylamines/amphetamines and cannabinoids were the NPS classes most found in the fatal cases. In many cases, multiple compounds were detected in the biological samples, including prescription and other illegal drugs. Liquid chromatography-tandem mass spectrometry, an alternative to overcome the gas chromatography-mass spectrometry limitations for some compounds, was the analytical technique most used in the studies, and high resolution mass spectrometry was often applied to NPS metabolite investigation and structural characterization and identification of unknown compounds. Toxicological screening and quantitation methods need to be continuously updated to include new substances that are emerging on the drug market that can be fatal at very low doses.

An Update on the Implications of New Psychoactive Substances in Public Health

The emergence of new psychoactive substances has earned a great deal of attention, and several reports of acute poisoning and deaths have been issued involving, for instance, synthetic opiates. In recent years, there have been profound alterations in the legislation concerning consumption, marketing, and synthesis of these compounds; rapid alert systems have also been subject to changes, and new substances and new markets, mainly through the internet, have appeared. Their effects and how they originate in consumers are still mostly unknown, primarily in what concerns chronic toxicity. This review intends to provide a detailed description of these substances from the point of view of consumption, toxicokinetics, and health consequences, including case reports on intoxications in order to help researchers and public health agents working daily in this area.

Synthetic Cathinones: Recent Developments, Enantioselectivity Studies and Enantioseparation Methods

New psychoactive substances represent a public health threat since they are not controlled by international conventions, are easily accessible online and are sold as a legal alternative to illicit drugs. Among them, synthetic cathinones are widely abused due to their stimulant and hallucinogenic effects. To circumvent the law, new derivatives are clandestinely synthesized and, therefore, synthetic cathinones keep emerging on the drug market, with their chemical and toxicological properties still unknown. In this review, a literature assessment about synthetic cathinones is presented focusing on the recent developments, which include more than 50 derivatives since 2014. A summary of their toxicokinetic and toxicodynamic properties are also presented. Furthermore, synthetic cathinones are chiral compounds, meaning that they can exist as two enantiomeric forms which may present different biological and toxicological activities. To analyze the enantiomers, the development of enantiomeric resolution methods for synthetic cathinones is crucial. Many methods have been reported over the years that include mostly chromatographic and electromigration techniques, with liquid chromatography using chiral stationary phases being the technique of choice. This review intended to present an overview of enantioselectivity studies and enantioseparation analysis regarding synthetic cathinones, highlighting the relevance of chirality and current trends.

Crystallographic characterization of three cathinone hydrochlorides new on the NPS market: 1-(4-methylphenyl)-2-(pyrrolidin-1-yl)hexan-1-one (4-MPHP), 4-methyl-1-phenyl-2-(pyrrolidin-1-yl)pentan-1-one (α-PiHP) and 2-(methylamino)-1-(4-methylphenyl)pentan-1-one (4-MPD)

Cathinones belong to a group of compounds of great interest in the new psychoactive substances (NPS) market. Constant changes to the chemical structure made by the producers of these compounds require a quick reaction from analytical laboratories in ascertaining their characteristics. In this article, three cathinone derivatives were characterized by X-ray crystallography. The investigated compounds were confirmed as: 1-[1-(4-methylphenyl)-1-oxohexan-2-yl]pyrrolidin-1-ium chloride (1, C₁₇H₂₆NO⁺·Cl^-, the hydrochloride of 4-MPHP), 1-(4-methyl-1-oxo-1-phenylpentan-2-yl)pyrrolidin-1-ium chloride (2; C₁₆H₂₄NO⁺·Cl^-, the hydrochloride of α-PiHP) and methyl[1-(4-methylphenyl)-1-oxopentan-2-yl]azanium chloride (3; C₁₃H₂₀NO⁺·Cl^-, the hydrochloride of 4-MPD). All the salts crystallize in a monoclinic space group: 1 and 2 in P2₁/c, and 3 in P2₁/n. To the best of our knowledge, this study provides the first detailed and comprehensive crystallographic data on salts 1-3.

Severe poisoning after smoking a mixture of 4-fluoroisobutyryl fentanyl (4-FiBF) and alpha-pyrolidinoisohexaphenone (α-PiHP)

CONTEXT

Intoxications after ingestion of new psychoactive substances are currently one of the most challenging issues in clinical toxicology. Synthetic cathinones represented the largest group of drugs seized in 2020, but the increasing distribution of fentanyl analogues is resulting in a growing global opioid crisis. In addition, synthetic opioids may be intentionally combined with psychostimulants by drug manufacturers to reduce depressive effects. We report a case of severe poisoning after smoking a mixture of 4-fluoroisobutyryl fentanyl (4-FiBF) and alpha-pyrrolidinoisohexaphenone (α-PiHP).

CASE DETAILS

A 29-year-old male was found out of conscious in his apartment and taken to the Intensive Care Unit. Examinations revealed pinpoint pupils, slight respiratory acidosis, leukocytosis as well as body temperature of 39.4 °C and increased creatinine with decreased eGFR level. Toxicological analysis of biological samples revealed presence of 4-FiBF and α-PiHP in concentrations: 87.7 ng/mL and 5.0 ng/mL (blood) and 2291.0 ng/mL and 722.2 ng/mL (urine), respectively. After 4 days, the patient was discharged home.

DISCUSSION

Unique combination of clinical symptoms was a result of a simultaneous 4-FiBF and α-PiHP intoxication. To our knowledge, this is the first case of ingestion such unusual mixture of new psychoactive substances with a full description of medical treatment.

Fatal N-Ethylhexedrone Intoxication

N-Ethylhexedrone [2-(ethyloamino)-1-phenylhexan-1-one; α-ethylaminohexanophenone (NEH)] is one of the most recent synthetic cathinones that appeared on the illegal market in late 2015. The majority of information concerning the model of consumption of NEH and its impact on the body originates only from self-reports from gray literature websites and drug forums. There are only limited data associated with the concentrations of NEH in blood samples available in the literature. This article presents a case of fatal NEH intoxication and a method for the determination of this substance in whole blood. A 21-year-old man without any diagnosed diseases was admitted to the hospital due to disorientation, aggression and finally loss of consciousness. Hyperthermia (>41°C), tachycardia (>160 beats per minute), tachypnea (20 breaths per minute), blood pressure (110/60 mmHg) and acute kidney failure were diagnosed. After a few hours of hospitalization, the patient died. A plastic bag with a white powder was found in his underwear. Analysis of the powder by another laboratory revealed cocaine hydrochloride; however, no cocaine or its metabolites were found in the biological material upon testing in our laboratory. Therefore, re-analysis of the powder was performed, and NEH was identified. Liquid–liquid extraction followed by liquid chromatography-triple quadrupole-mass spectrometry (LC-MS/MS) analysis were used for the determination of NEH in blood. The validation parameters were as follows: calibration range 1–250 ng/mL, accuracy 106.5–109.9%, precision 3.5–6.3%, recovery 90.1–96.9%, limit of detection 0.07 ng/mL and limit of quantification 1 ng/mL. NEH was quantified in the blood at a concentration of 145 ng/mL. Additionally, amphetamine at low concentrations and 11-nor-9-karboksy-Δ9-tetrahydrokannabinol (THC-COOH) were detected.

Our study provided information on the possible lethal concentration and toxidrome that clinicians can observe for NEH-intoxicated patients and can be helpful during the preparation of toxicology analysis reports for a court of law for proper data interpretation.

An updated review on synthetic cathinones

Cathinone, the main psychoactive compound found in the plant Catha edulis Forsk. (khat), is a β-keto analogue of amphetamine, sharing not only the phenethylamine structure, but also the amphetamine-like stimulant effects. Synthetic cathinones are derivatives of the naturally occurring cathinone that largely entered the recreational drug market at the end of 2000s. The former "legal status", impressive marketing strategies and their commercial availability, either in the so-called "smartshops" or via the Internet, prompted their large spread, contributing to their increasing popularity in the following years. As their popularity increased, the risks posed for public health became clear, with several reports of intoxications and deaths involving these substances appearing both in the social media and scientific literature. The regulatory measures introduced thereafter to halt these trending drugs of abuse have proved to be of low impact, as a continuous emergence of new non-controlled derivatives keep appearing to replace those prohibited. Users resort to synthetic cathinones due to their psychostimulant properties but are often unaware of the dangers they may incur when using these substances. Therefore, studies aimed at unveiling the pharmacological and toxicological properties of these substances are imperative, as they will provide increased expertise to the clinicians that face this problem on a daily basis. The present work provides a comprehensive review on history and legal status, chemistry, pharmacokinetics, pharmacodynamics, adverse effects and lethality in humans, as well as on the current knowledge of the neurotoxic mechanisms of synthetic cathinones.

A Review of Synthetic Cathinone-Related Fatalities From 2017 to 2020

BACKGROUND

Synthetic cathinones (SCs) are designer analogs of the natural active principle of khat. Since their appearance on the black market in 2003, their popularity has increased annually, and they have become the most seized class of new psychoactive substances reported to the UNODC Early Warning Advisory system. The constant introduction of newly synthesized molecules makes this issue difficult to monitor. The authors reviewed the most recent SC-related fatalities worldwide to highlight new trends of consumption, reporting acute pharmacological and toxicological symptoms, scene investigations, analytical methods, and reported SC concentrations in diverse biological matrices.

METHODS

A literature search was performed using scientific databases such as PubMed, Scopus, Science Direct, Web of Science, and Research Gate to identify relevant scientific publications from 2017 to 2020. In addition, a search was conducted through the EU EWS.

RESULTS

From 2017 to 2020, 31 different SCs were identified in 75 reported fatal intoxications in the literature, alone or in combination with other substances. The most abused SCs were N-ethylpentylone, N-ethylhexedrone, and 4-chloromethcathinone. The EU EWS included less detail on 72 additional SC-related fatalities from 2017 to 2020.

CONCLUSIONS

New SCs continuously replace older natural and synthetic stimulant drugs, making determining the cause of death difficult. Analytical methods and high-performance mass spectrometry instruments are essential to detect the low concentrations of these potent new SCs. Little data are available on the pharmacology of these new drugs; the evaluation of toxicological antemortem and postmortem findings provides critical data on the drug's pharmacology and toxicology and for the interpretation of new SC cases.

Screening of 104 New Psychoactive Substances (NPS) and Other Drugs of Abuse in Oral Fluid by LC–MS-MS

New psychoactive substances (NPS) are a major public health problem, primarily due to the increased number of acute poisoning cases. Detection of these substances is a challenge. The aim of this research was to develop and validate a sensitive screening method for 104 drugs of abuse, including synthetic cannabinoids, synthetic cathinones, fentanyl analogues, phenethylamines and other abused psychoactive compounds (i.e., THC, MDMA, LSD and their metabolites) in oral fluid by liquid chromatography–tandem mass spectrometry (LC–MS-MS). The Quantisal™ oral fluid device was used to collect oral fluid samples. The oral fluid–elution buffer mixture (500-μL sample) was extracted with t-butyl methyl ether, and chromatographic separation was performed on a Raptor™ biphenyl column (100 × 2.1 mm ID, 2.7 μm), with a total run time of 13.5 min. Limits of detection were established at three concentrations (0.05, 0.1 or 1 ng/mL) for most analytes, except for acetyl norfentanyl and mescaline (5 ng/mL). Matrix effects were generally <20% and overall extraction recoveries >60%. The highest matrix effect was observed within the synthetic cannabinoid group (PB22, −55.5%). Lower recoveries were observed for 2C-T (47.2%) and JWH-175 (58.7%). Recoveries from the Quantisal™ device were also evaluated for all analytes (56.7–127%), with lower recoveries noted for 25I-NBOMe, valerylfentanyl and mCPP (56.7, 63.0 and 69.9%, respectively). Drug stability in oral fluid was evaluated at 15, 60 and 90 days and at 25, 4 and −20°C. As expected, greater stability was observed when samples were stored at −20°C, but even when frozen, some NPS (e.g., synthetic cannabinoids) showed more than 20% degradation. The method was successfully applied to the analysis of seven authentic oral fluid samples positive for 17 different analytes. The method achieved good sensitivity and simultaneous detection of a wide range of NPS.

Four Synthetic Cathinones: 3-Chloromethcathinone, 4-Chloromethcathinone, 4-Fluoro-α-Pyrrolidinopentiophenone, and 4-Methoxy-α-Pyrrolidinopentiophenone Produce Changes in the Spontaneous Locomotor Activity and Motor Performance in Mice with Varied Profiles

Two chloromethcathinones, 3-chloromethcathinone (3-CMC) and 4-chloromethcathinone (4-CMC), and two para-substituted α-pyrrolidinophenones, 4-methoxy-α-pyrrolidinopentiophenone (4-MeO-PVP) and 4-fluoro-α-pyrrolidinopentiophenone (4-F-PVP), represent synthetic cathinones, the second most frequently abused group of new psychoactive substances (NPSs), which has aroused a worldwide health concern in the last decade. Synthetic cathinones act as psychostimulants by elevating extracellular levels of monoaminergic neurotransmitters. This study investigates effects of 3-CMC, 4-CMC, 4-MeO-PVP, and 4-F-PVP on the spontaneous locomotor activity and motor performance of mice. Additionally, neurotoxicity of substituted methcathinones against SH-SY5Y neuroblastoma cells was evaluated. All test cathinones stimulate in a dose-dependent manner horizontal locomotor activity of mice. Consistently to our prior findings, pyrrovalerones, but not methcathinone derivatives, produce dose-dependent elevation of vertical locomotor activity (rearing behavior). None of the tested compounds decreases the time spent on the accelerating rotarod, pointing to the lack of considerable motor disability in mice after acute exposition. Only 4-MeO-PVP at the high tested dose (20 mg/kg) increases motor performance of mice. Considering that α-pyrrolidinophenones are highly potent and selective DA uptake inhibitors, while chloromethcathinones enhance non-selective DA/5-HT release, we suggest that the increase of vertical locomotor activity and performance on rotarod in mice may serve as a behavioral indicator of the monoaminergic profile of synthetic cathinones. Finally, this study gives first insights into cytotoxicity of both 3-CMC and 4-CMC displayed against SH-SY5Y cells, which emerges and intensifies after prolonged incubation, suggesting the indirect mechanism of action, unrelated to interactions with monoamine transporters.