Toxicological Analysis of Intoxications with Synthetic Cathinones

Synthetic Cathinones Induce Developmental Arrest, Reduce Reproductive Capacity, and Shorten Lifespan in the C. elegans Model

Drug abuse presents a significant global health challenge as the illicit drug market progresses from classic drugs to a growing prevalence of New Psychoactive Substances (NPS), particularly synthetic cathinones, which, although illegal, are often falsely marketed as safe and legal alternatives. The rapid increase in the use of these drugs complicates the assessment of their safety and effects on human health. However, they pose unique toxicological concerns that remain largely uncharacterized. This study investigated the toxic effects of three synthetic cathinones, namely, methylone, pentedrone, and 4-methylethcathinone (4-MEC), using the model organism C. elegans. We assessed the impact of these substances on animal survival, development, reproductive behavior, and longevity. Our results showed that short-term exposure (24 h) to concentrations of 5.0 mM or higher significantly reduced animal survival rates, while prolonged exposure (72 h) led to more pronounced toxicity, significantly reducing survival rates at concentrations as low as 1.0 mM. Moreover, sublethal concentrations resulted in developmental arrest. Additionally, pentedrone impaired reproductive capacity, while 4-MEC significantly shortened C. elegans lifespan. These findings highlight the urgent need for further investigation into the implications of synthetic cathinone use on human health through in vivo models as their prevalence in the illicit drug market continues to rise.

Comprehensive evaluation of the toxicological effects of commonly encountered synthetic cathinones using in silico methods

Synthetic cathinones (SCs), a group of new psychoactive substances (NPS), are designer molecules with hallucinogenic and psychostimulatory effects. Although the structural similarities of SCs to amphetamines suggest that they may have similar toxicity profiles to those of amphetamine congeners, little is known about SCs from a toxicological point of view. In the present study, the toxicity profiles of commonly encountered SCs (n = 65), listed in the 2020 Report of the United Nations Office on Drugs and Crime (UNODC), were evaluated using in silico methods. We aimed to gain a deeper understanding of key toxicological endpoints: acute oral toxicity (LD50), mutagenicity, genotoxicity, and carcinogenicity prediction using EPA TEST (v.5.1.2 and 4.2.1), VEGA (v.1.2.3), and ProTox (v.3.0). Physicochemical and pharmacokinetic (ADME) properties were estimated using SwissADME and pkCSM. 2,3-MDMC (41) was predicted to be the most lethal SC by the VEGA KNN and the EPA TEST v.5.1.2 with an oral rat LD50 value of 105.17 and 117.77 mg/kg, respectively. 4-BEC (2) was the only molecule with a consensus score of positive prediction greater than 0.90 in both TEST mutagenicity models. 2,3-MDMC (41) and methylone (52) were predicted as carcinogenic by VEGA carcinogenicity CAESAR, ISS, IRFMN-ISSCAN-CGX, oral classification, and ProTox models. These two SCs were predicted to be active by VEGA chromosomal aberration (CORAL) and in vitro micronuclei-inducing activity (IRFMN-VERMEER) models. Our results concluded that given the prolonged exposure duration and age range, the genotoxic and carcinogenic potential of SCs should be considered, among other known toxic effects.

Mephedrone concentrations in clinical intoxications and fatal cases: a systematic review

BACKGROUND/PURPOSE

Mephedrone, a ring-substituted synthetic cathinone derivative, gained popularity as a recreational drug in the late 2000s. Reports of fatalities related to mephedrone use have emerged with varying concentrations of blood mephedrone upon forensic investigations. This study aims to evaluate the existing literature on mephedrone concentrations in instances of clinical intoxication and fatal cases.

METHODS

We comprehensively searched electronic databases, including Web of Science, PubMed, Embase, and the Cochrane Library, from inception to July 26, 2023. We selected case reports or case series of mephedrone intoxication presented with individual blood mephedrone concentration. Patient demographics, clinical characteristics, blood mephedrone concentrations, and outcomes were extracted for analysis.

RESULTS

77 cases from 14 case reports and 6 case series were identified for review. There were 34 deaths and 43 non-fatal intoxication cases. The median patient's age was 24 years (IQR: 10), and 91.4% were male. Forty-five of the 63 cases (71.4%) were reported with alcohol or other illicit drugs detected. The median blood mephedrone concentration was 0.37 mg/L (IQR: 1.09 mg/L). Death cases were older than non-fatal cases (median = 30 vs. 22 years, p = 0.029). The median blood mephedrone concentration was higher in death cases (1.30 mg/L vs. 0.12 mg/L, p < 0.0001).

CONCLUSIONS

Blood mephedrone concentration in dead patients is approximately 11 times higher than in non-fatal cases. This finding could serve as a stepping stone to the diagnosis of concentrations in clinical poisoning cases and deaths, especially in the treatment of poisoning patients. In more extensive prospective studies, further research is necessary to establish a standardized, real-time available methodology and validate the predictive value of mephedrone concentrations in the prognostic value of mephedrone concentrations.

New psychoactive substances - 96 cases of deaths related to their use based on the material originating from forensic toxicological practice

Among the emerging investigative fields, forensic medicine and toxicology lead to analyzing fatalities in medico-legal expert opinion formulating. While discussing the problem, the authors have selected 96 fatal cases from their expert practice including the period from 2010 to 2023, in which deaths were connected with taking new psychoactive substances (NPS's) belonging to various chemical categories, mainly synthetic cathinones (SC), synthetic cannabinoids (SCan) and non-medical synthetic opioids (NSO). In the investigated cases, toxicological analysis revealed 37 NPS's and their 9 metabolites. The cases involved the use of SC's (64 cases - 67 %), Scan's, including their metabolites (10 cases - 10 %) and NSO's, including their metabolites (6 cases - 6 %). The remaining cases involved the simultaneous use of NSO with SC and/or SCan, including their metabolites (8 cases - 8 %), or SC with SCan (5 cases - 5 %). In three cases (3 %), compounds belonging to other groups were taken. In twenty-five cases, more than one NPS was found. Moreover, in twenty-seven cases, ethyl alcohol was also detected at the concentration range of 0.6-3.6 ‰. The concentration of xenobiotics determined in blood represented extensive ranges of concentration. The victims were at the age of 16-58 years of life. The group included eleven women (11 %). Generally, the deaths related to NPS's were predominantly of an accidental character (81 %), while the manner of death in sixteen cases (17 %) was suicide, including hanging (5 cases), jumping from a great height (3 cases), self-injury and exsanguination (1 case), as well as acute drug intoxication (6 cases) and intoxication with central nervous system hypoxia after an hanging (1 case). Among the analyzed cases there were two victims of homicide (2 %), in one of which the perpetrator being under the influence of the mixture of the synthetic opioid U-47700 and synthetic cannabinoid AB-FUBINACA. In twenty-eight cases, medications used in psychiatry were found, which suggested that the victims were struggling with mental problems before death. As it was implied by the available information, more than 36 % of the victims had mental problems.

Challenges encountered in the enantioselective analysis of new psychoactive substances exemplified by clephedrone (4-CMC)

In this study we report on efforts to develop an enantioselective method for the detection of the drug of abuse clephedrone (1-(4-chlorophenyl)-2-(methylamino)-1-propanone (4-chloromethcathinone, also known as 4-CMC or para-chloro-methcathinone)) and its phase-1 metabolites in human biological fluids. The major goal is not to only report results, but primarily to emphasize the various challenges encountered when developing a reliable analytical method for the detection and quantification of novel psychoactive substances (NPS) and their metabolites in the matrix of interest. Such challenges start with the lack of chemical stability of some NPS in biological matrices. Additionally, most often metabolites are unavailable in pure form to serve as analytical standards, just as deuterated standards for native drugs and metabolites are frequently not commercially available. Furthermore, if the NPS is chiral, enantiomerically pure standards with known absolute stereochemistry are required, as well as a stereochemical stability of a drug and its metabolites becomes an issue. In addition, the chirality of a NPS significantly increases the number of species to be detected in the sample and thus challenges the development of an adequate separation method. These issues are shortly addressed, and some solutions offered in this manuscript.

Structure-Activity Relationship of Synthetic Cathinones: An Updated Review

The escalating prevalence of new psychoactive substances (NPSs) poses a significant public health challenge, evidenced by the vast chemical diversity, with over 500 substances reported annually to the United Nations Office on Drugs and Crime-Early Warning Advisory (UNODC-EWA) in the past five years. Among NPSs, synthetic cathinones are gaining a lot of popularity among users. Notably, synthetic cathinones accounted for approximately 50% of the total quantity of NPSs reported as seized by EU Member States in 2021. Preliminary data from UNODC indicates that a total of 209 synthetic cathinones have been reported to date. As their popularity grows, studying the structure-activity relationship (SAR) of synthetic cathinones is essential. SAR studies elucidate how structural features impact biological effects, aiding in toxicity prediction, regulatory compliance, and forensic identification. Additionally, SAR studies play a pivotal role in guiding drug policies, aiding authorities in categorizing and regulating newly emerging synthetic cathinones, mitigate public health risks and offer valuable insights into potential therapeutic applications. Thus, our Review consolidates recent findings on the effects of different substitutions in the chemical scaffold of synthetic cathinones on their mechanism of action as well as pharmacological and toxicological effects of synthetic cathinones, thus enhancing understanding of the SAR of synthetic cathinones' pharmacology and potential implications.

Detection of the synthetic cathinone N,N-dimethylpentylone in seized samples from prisons

Drug use is prevalent in prisons with drugs associated with depressant effects found to be more prevalent than stimulants. Synthetic cathinones (SCats; often sold as "bath salts", "ecstasy", "molly", and "monkey dust") are the second largest category of new psychoactive substances (NPS) currently monitored by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) and are commonly used as substitutes for regulated stimulants, such as amphetamine, cocaine, and MDMA. N,N-dimethylpentylone (also known as dimethylpentylone, dipentylone, and bk-DMBDP) was detected for the first time in the Scottish prisons in seven powder samples seized between January and July 2023. Samples were analyzed using gas chromatography-mass spectrometry (GC-MS), ultra-high performance liquid chromatography-quadrupole time of flight mass spectrometry (UPLC-QToF-MS), and nuclear magnetic resonance imaging (NMR). Dimethylpentylone was detected alongside other drugs in four samples, including the novel benzodiazepine desalkylgidazepam (bromonordiazepam) and the synthetic cannabinoid receptor agonists (SCRAs) MDMB-INACA and MDMB-4en-PINACA.

Solvent-free parallel artificial liquid membrane extraction for drugs of abuse in plasma samples using LC-MS/MS

BACKGROUND

Parallel artificial liquid membrane extraction (PALME) is a 96-well plate setup variant of liquid-phase microextraction. Basic or acidic analytes are extracted in neutral form from the sample, through a supported liquid membrane (SLM), and into aqueous acceptor. PALME is already considered a green extraction technique, but in the current conceptual work, we sought to make it even greener by replacing the use of organic solvents with essential oils (EO). PALME was combined with LC-MS/MS for analysis of plasma samples and multiple drugs of abuse with toxicological relevance (amphetamines, phenethylamines, synthetic cathinones, designer benzodiazepines, ayahuasca alkaloids, lysergic acid diethylamide, and ketamine).

RESULTS

Fourteen EO were compared to organic solvents frequently used in PALME. The EO termed smart & sassy yielded the best analyte recovery for all drugs studied and was thus selected as SLM. Then, factorial screening and Box-Behnken were employed to optimize the technique. The extraction time, concentration of base, sample volume, and percentage of trioctylamine significantly impacted analyte recovery. The optimum values were defined as 120 min, 10 mmol/L of NaOH, 150 μL, and 0%, respectively. Once optimized, validation parameters were 1-100 ng mL-1 as linear range, accuracy ±16.4%, precision >83%, 1 ng mL-1 as limit of quantitation, 0.1-0.75 ng mL-1 as limit of detection, matrix effect <20%, and recovery 20-106%. Additionally, EO purchased from different production batches were tested and achieved acceptable reproducibility. Data were in compliance with requirements set by internationally accepted validation guidelines and the applicability of the technique was proven using authentic samples.

SIGNIFICANCE

In this study, the use of an EO provided a solvent-free sample preparation technique suited to extract different classes of drugs of abuse from plasma samples, dismissing the use of hazardous organic solvents. The method also provided excellent sample clean-up, thus being a simple and efficient tool for toxicological applications that is in agreement with the principles of sustainable chemistry.

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.

Pharmacological profile, phase I metabolism, and excretion time profile of the new synthetic cathinone 3,4-Pr-PipVP

1-(2,3-Dihydro-1H-inden-5-yl)-2-(piperidin-1-yl)pentan-1-one (3,4-Pr-PipVP), a novel synthetic cathinone (SCat), was first identified in 2022 in Germany. The product was marketed as 1-(bicyclo[4.2.0]octa-1,3,5-trien-3-yl)-2-(pyrrolidin-1-yl)pentan-1-one (3,4-EtPV), a substance not covered by the German New Psychoactive Substances Act (NpSG). Although originally intended to be an exploratory new synthetic cathinone containing the novel bicyclo[4.2.0]octatrienyl function, the compound was subsequently confirmed to contain an indanyl ring system scheduled under generic legislation like the NpSG. However, it is one of only a few marketed SCats carrying a piperidine ring. Inhibition experiments involving norepinephrine, dopamine, and serotonin transporters showed that 3,4-Pr-PipVP was a low potency blocker at all three monoamine transporters compared to related substances such as MDPV. Additionally, pharmacokinetic data were collected from pooled human liver microsomes incubations and from the analysis of authentic urine samples received after oral administration of 5 mg 3,4-Pr-PipVP hydrochloride. Phase I metabolites were tentatively identified in vitro and in vivo using liquid chromatography-time-of-flight mass spectrometry. Main metabolites were formed by metabolic reduction of the carbonyl function with and without additional hydroxylations at the propylene bridge of the molecule. Keto-reduced H2 -3,4-Pr-PipVP and H2 -piperidine-OH-3,4-Pr-PipVP as well as aryl-OH-3,4-Pr-PipVP, and indanyl-OH-piperidine-OH-3,4-Pr-PipVP are suggested as most suitable biomarkers for the detection of 3,4-Pr-PipVP since they were detected for much longer than the parent compound. 3,4-Pr-PipVP could be detected for up to 21 h whereas its metabolites were detectable for up to about 4 days.

Metabolic Stability and Metabolite Identification of N-Ethyl Pentedrone Using Rat, Mouse and Human Liver Microsomes

New Psychoactive Substances (NPSs) are defined as a group of substances produced from molecular modifications of traditional drugs. These molecules represent a public health problem since information about their metabolites and toxicity is poorly understood. N-ethyl pentedrone (NEP) is an NPS that was identified in the illicit market for the first time in the mid-2010s, with four intoxication cases later described in the literature. This study aims to evaluate the metabolic stability of NEP as well as to identify its metabolites using three liver microsomes models. To investigate metabolic stability, NEP was incubated with rat (RLM), mouse (MLM) and human (HLM) liver microsomes and its concentration over time evaluated by liquid chromatography-mass spectrometry. For metabolite identification, the same procedure was employed, but the samples were analyzed by liquid chromatography-high resolution mass spectrometry. Different metabolism profiles were observed depending on the model employed and kinetic parameters were determined. The in vitro NEP elimination half-lives (t1/2) were 12.1, 187 and 770 min for the rat, mouse and human models, respectively. Additionally, in vitro intrinsic clearances (Cl int, in vitro) were 229 for rat, 14.8 for mouse, and 3.6 μL/min/mg in the human model, and in vivo intrinsic clearances (Cl int, in vivo) 128, 58.3, and 3.7 mL/min/kg, respectively. The HLM model had the lowest rate of metabolism when compared to RLM and MLM. Also, twelve NEP metabolites were identified from all models, but at different rates of production.

Green analytical toxicology method for determination of synthetic cathinones in oral fluid samples by microextraction by packed sorbent and liquid chromatography-tandem mass spectrometry

PURPOSE

We developed and validated a method for quantitative analysis of ten synthetic cathinones in oral fluid (OF) samples, using microextraction by packed sorbent (MEPS) for sample preparation followed by liquid chromatography‒tandem mass spectrometry (LC‒MS/MS).

METHOD

OF samples were collected with a Quantisal™ device and 200 µL was extracted using a C18 MEPS cartridge installed on a semi-automated pipette and then analyzed using LC‒M/SMS.

RESULTS

Linearity was achieved between 0.1 and 25 ng/mL, with a limit of detection (LOD) of 0.05 ng/mL and a limit of quantification (LOQ) of 0.1 ng/mL. Imprecision (% relative standard deviation) and bias (%) were better than 11.6% and 7.5%, respectively. The method had good specificity and selectivity against 9 different blank OF samples (from different donors) and 68 pharmaceutical and drugs of abuse with concentrations varying between 400 and 10,000 ng/mL. No evidence of carryover was observed. The analytes were stable after three freeze/thaw cycles and when kept in the autosampler (10 °C) for up to 24 h. The method was successfully applied to quantify 41 authentic positive samples. Methylone (mean 0.6 ng/mL, median 0.2 ng/mL), N-ethylpentylone (mean 16.7 ng/mL, median 0.35 ng/mL), eutylone (mean 39.1 ng/mL, median 3.6 ng/mL), mephedrone (mean 0.5 ng/mL, median 0.5 ng/mL), and 4-chloroethcathinone (8.1 ng/mL) were quantified in these samples.

CONCLUSION

MEPS was an efficient technique for Green Analytical Toxicology purposes, which required only 650 µL organic solvent and 200 µL sodium hydroxide, and the BIN cartridge had a lifespan of 100 sample extractions.

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.

Synergistic Multieffect Catalytic Amplified Cathodic Electrochemiluminescence Biosensor via Target Binding-Induced Aptamer Conformational Changes for the Ultrasensitive Detection of Synthetic Cathinone

Signal amplification is a powerful approach to increasing the detection sensitivity of electrochemiluminescence (ECL). Here, we developed synergistic multieffect catalytic strategies based on CuCo2O4 nanorod combination of Ag NPs as coreaction accelerators to fabricate an efficient covalent organic framework (PTCA-COF)-based ternary ECL biosensor. Concretely, the high redox reversibility of Co3+/Co2+ and Cu2+/Cu+ would constantly promote the decomposition of S2O82- for ECL emission. Meanwhile, the introduction of Ag NPs with excellent electrocatalytic activity further realized multiple amplification of the ECL signal. Furthermore, the good hydrogen evolution reaction (HER) ability of Ag@CuCo2O4 nanorods could accelerate the proton transmission rate of the system to amplify ECL behavior. In the presence of the target synthetic cathinone 4-chloroethcathinone (4-CEC) as the quenching ECL signal-response probe, the Ferrocene (Fc)-labeled aptamer folded into the conformationally limited stem-loop structure, bringing Fc near the ECL luminophore and resulting in quenched ECL emission. The quenching effect was connected with target-induced aptamer conformational changes and consequently reflected the target concentration. Under optimum conditions, the proposed biosensor realized a highly sensitive assay for 4-CEC with a large dynamic range from 1.0 × 10-12 to 1.0 × 10-6 g/L and a detection limit as low as 2.5 × 10-13 g/L. This study integrated multiple amplification strategies for efficient ECL enhancement, which provided a novel approach to constructing highly bioactive and sensitive sensors.

First-Generation Synthetic Cathinones Produce Arrhythmia in Zebrafish Eleutheroembryos: A New Approach Methodology for New Psychoactive Substances Cardiotoxicity Evaluation

The increasing number of new psychoactive substances (NPS) entering the illicit drug market, especially synthetic cathinones, as well as the risk of cardiovascular complications, is intensifying the need to quickly assess their cardiotoxic potential. The present study aims to evaluate the cardiovascular toxicity and lethality induced by first-generation synthetic cathinones (mephedrone, methylone, and MDPV) and more classical psychostimulants (cocaine and MDMA) in zebrafish embryos using a new approach methodology (NAM). Zebrafish embryos at 4 dpf were exposed to the test drugs for 24 h to identify drug lethality. Drug-induced effects on ventricular and atrial heart rate after 2 h exposure were evaluated, and video recordings were properly analyzed. All illicit drugs displayed similar 24 h LC50 values. Our results indicate that all drugs are able to induce bradycardia, arrhythmia, and atrial-ventricular block (AV block), signs of QT interval prolongation. However, only MDPV induced a different rhythmicity change depending on the chamber and was the most potent bradycardia and AV block-inducing drug compared to the other tested compounds. In summary, our results strongly suggest that the NAM presented in this study can be used for screening NPS for their cardiotoxic effect and especially for their ability to prolong the QT intervals.

Method development, validation, and application for simultaneous determination of 56 new psychoactive substances in surface water by LC-MS/MS

Despite preventive legislation, the popularity and consumption of new psychoactive substances (NPS) have been steadily increasing in recent years. This study provides a rapid and sensitive method for the quantitation and the detection of 56 NPS from surface water. Sample clean-up and pre-concentration were performed by solid-phase extraction (SPE) with Oasis HLB (6 cc/500 mg) cartridge. Following the chromatographic separation with Shim-pack FC-ODS column, the all substances were quantified by liquid chromatography-tandem mass spectrometry. The method was optimized and validated for all NPS. Despite the wide variety of physicochemical properties of the analytes, the recoveries for all compounds studied were in the range of 69-117%. The limit of quantitation (LOQ) ranging from 2.5 to 15 ng/L was reached for reliable and accurate quantification of analytes. The analytical method developed was successfully applied to the surface water samples. While synthetic cannabinoids were not detected, mephedrone from the synthetic cathinone group was detected under the LOQ. This novel method was expected to be a part of future environmental routine analyses as a satisfactory method.

GC-MS/MS Determination of Synthetic Cathinones: 4-chloromethcathinone, N-ethyl Pentedrone, and N-ethyl Hexedrone in Oral Fluid and Sweat of Consumers under Controlled Administration: Pilot Study

This study presents a validated GC-MS/MS method for the detection and quantification of 4-chloromethcathinone or clephedrone (4-CMC), N-ethyl Pentedrone (NEP), and N-ethyl Hexedrone (NEH, also named HEXEN) in oral fluid and sweat and verifies its feasibility in determining human oral fluid concentrations and pharmacokinetics following the administration of 100 mg of 4-CMC orally and 30 mg of NEP and NEH intranasally. A total of 48 oral fluid and 12 sweat samples were collected from six consumers. After the addition of 5 μL of methylone-d₃ and 200 μL of 0.5 M ammonium hydrogen carbonate, an L/L extraction was carried out using ethyl acetate. The samples, dried under a nitrogen flow, were then derivatized with pentafluoropropionic anhydride and dried again. One microliter of the sample reconstituted in 50 μL of ethyl acetate was injected into GC-MS/MS. The method was fully validated according to international guidelines. Our results showed how, in oral fluid, the two cathinones taken intranasally were absorbed very rapidly, within the first hour, when compared with the 4-CMC which reached its maximum concentration peak in the first three hours. We observed that these cathinones were excreted in sweat in an amount equivalent to approximately 0.3% of the administered dose for 4-CMC and NEP. The total NEH excreted in sweat 4 h after administration was approximately 0.2% of the administered dose. Our results provide, for the first time, preliminary information about the disposition of these synthetic cathinones in the consumers' oral fluid and sweat after controlled administration.

Synthetic Cathinones and Neurotoxicity Risks: A Systematic Review

According to the EU Early Warning System (EWS), synthetic cathinones (SCs) are the second largest new psychoactive substances (NPS) class, with 162 synthetic cathinones monitored by the EU EWS. They have a similar structure to cathinone, principally found in Catha Edulis; they have a phenethylamine related structure but also exhibit amphetamine-like stimulant effects. Illegal laboratories regularly develop new substances and place them on the market. For this reason, during the last decade this class of substances has presented a great challenge for public health and forensic toxicologists. Acting on different systems and with various mechanisms of action, the spectrum of side effects caused by the intake of these drugs of abuse is very broad. To date, most studies have focused on the substances’ cardiac effects, and very few on their associated neurotoxicity. Specifically, synthetic cathinones appear to be involved in different neurological events, including increased alertness, mild agitation, severe psychosis, hyperthermia and death. A systematic literature search in PubMed and Scopus databases according to PRISMA guidelines was performed. A total of 515 studies published from 2005 to 2022 (350 articles from PubMed and 165 from Scopus) were initially screened for eligibility. The papers excluded, according to the criteria described in the Method Section (n = 401) and after full text analyses (n = 82), were 483 in total. The remaining 76 were included in the present review, as they met fully the inclusion criteria. The present work provides a comprehensive review on neurotoxic mechanisms of synthetic cathinones highlighting intoxication cases and fatalities in humans, as well as the toxic effects on animals (in particular rats, mice and zebrafish larvae). The reviewed studies showed brain-related adverse effects, including encephalopathy, coma and convulsions, and sympathomimetic and hallucinogenic toxidromes, together with the risk of developing excited/agitated delirium syndrome and serotonin syndrome.

Synthetic Cathinones in Belgium: Two Case Reports with Different Outcomes Observed in the Emergency Room

We herein report two cases of cathinone intoxication. The first case is about a drug addict who was admitted to the emergency room after the injection of an unknown compound. He presented with tachycardia, palpitations, mydriasis, dyspnea, dizziness, headache and nausea. After leaving the hospital against medical advice, he returned the next day with police escort, presenting aggressiveness and agitation signs. One month later, he returned one more time for sleeping disorders, hallucinations and anxiety. He was finally transferred for his 21st detoxification treatment. The second case concerns a man who was wandering the streets and tried to escape when police officers called him. He confessed to snorting of N-ethylpentedrone and was admitted with severe agitation including delusion of persecution, tachycardia, mydriasis and fever. Because of renal failure, rhabdomyolysis and metabolic acidosis, he was transferred to the intensive care unit where he manifested worsening of the symptoms, turning into coma. He was intubated for 3 days before a complete resolution of the symptoms. A screening was performed by high-resolution mass spectrometry followed by quantifications made by high-performance liquid chromatography coupled with a diode array detector. In the first case, alpha-pyrrolidinohexiophenone was identified only during the first two admissions. However, as plenty of other psychotropic substances were also found, the cathinone alone could not be held directly responsible for the symptoms. In the second case, more than 2,000 ng/mL of N-ethylpentedrone was found without any decrease in the next 17 h, underlining the long half-life of this compound. Unlike the first case, symptoms could be clearly attributed to the cathinone. In conclusion, cathinones can be found on the Belgian illicit drug market, with various routes of administration and clinical consequences. In these two case reports, some common points were observed initially. However, one patient was finally able to leave the hospital without any treatment, whereas the other would most likely have died without intensive care.

A fatal case involving the highest ever reported 4-CMC concentration

Synthetic cathinones comprise a large amount of substances present on the dark market, which creates an undeniably worldwide problem and still is posing a threat. A 22-year-old man was brought to the Emergency Room from a party, where he had ingested orally 20 g of mephedrone. The man exhibited a disorder of consciousness with no logical verbal contact and dilated pupils. Moreover, a metabolic acidosis was present. The patient died after an hour from an admission to the ER. Blood and vitreous humor collected during an autopsy were analyzed with the use of an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-QqQ-MS/MS) with the use of C18 column in multiple reaction monitoring (MRM) mode. Both biological specimens were prepared using liquid-liquid extraction (LLE) with the use of ethyl acetate and 0.5 M ammonium carbonate water solution (pH 9). The limit of quantification (LOQ) of the method was 0.5 ng/ml in both matrices; precision and accuracy values did not exceed ±15%. Recovery of the method was in the range of 86.1%-102.7%. Determined concentrations of 4-CMC were 8542 and 9874 ng/ml in blood and vitreous humor, respectively. Other substances present in both biological materials were: atropine, diazepam, lidocaine, and its metabolite norlidocaine, as well as methcathinone and ethyl alcohol. The concentration presented in here described case is the highest ever reported 4-CMC concentration. Important aspect is also receiving other NPS by recreational users than intended, which lead to accidental poisoning (in presented case user assumed 4-CMC was 4-MMC).

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.