Acute kidney damage and even kidney failure have been reported following use of synthetic cannabinoids (Davidson, et al., 2017). One recent study has looked at other mechanisms of action in some of the older synthetic cannabinoids and reported that some produced varying amounts of activity at sites which are related to cardiotoxicity and heart disease (Wiley et al., 2016). It is not known whether the increased toxicity is due only to activation of CB1 cannabinoid receptors more strongly than Δ9-THC or whether these "super-strength" cannabinoids produce effects at other receptors. A major cause of concern is that some of the more recently seen synthetic cannabinoids are more likely to produce extremely toxic effects than the older synthetics (Tai and Fantegrossi, 2017


Product ions detected at m/z 302, 217, and 145 (B2) confirmed that tert-leucine and indazole moieties remained unchanged, leading to the structure elucidation of a hydroxy-functional group at the 4-position of the butyl side chain by oxidative defluorination. The product ion m/z 336 (loss of methyl ester moiety) further confirmed the presence of dihydroxylated metabolites. The precursor ion, m/z 364 (B14, B5/B6) had a loss of 2 Da from m/z 366 indicated further dehydrogenation of the ester hydrolysis plus monohydroxylated metabolites. The presence of the product ion m/z 320, likely formed from a loss of carbon dioxide, indicated monohydroxylation at the tert-leucine in B8 (m/z 219), butyl side chain in B9 (m/z 145) and indazole moiety in B13 (m/z 161). The precursor ion, m/z 350 showed a loss of 14 Da explaining the hydrolysis of methyl ester from 4F-MDMB-BINACA.
Fig. 2.
4F-MDMB-BINACA was hydrolysed via ester hydrolysis forming the 4F-MDMB-BINACA ester hydrolysis metabolite (B22). Data obtained from the twenty urine samples were retrospectively analysed and processed using TraceFinder software based on the identification criteria of mass errors less than ± 5 ppm for full MS peaks and MS/MS peaks from the theoretical mass and matching of MS/MS spectra. The mixture was vortex-mixed and 500 µL of this mixture and 500 µL of methanol were loaded onto the Clean Screen FASt® tube. After incubation, the mixture was cooled at room temperature, and 150 µL of purified water was added. High-resolution QTOF-MS data were acquired on an Agilent 6510 Accurate Mass QTOF mass spectrometer (Agilent Technologies) equipped with dual electrospray ionization (ESI) source operated in both positive and negative ion modes, to determine accurate masses of the metabolites. Chromatographic separation was performed on an Agilent 1290 LC system with a Poroshell 120 EC-C18 analytical column (2.7 μm, 75 × 2.1 mm; Agilent Technologies, Santa Clara, CA, USA).
Fig. 1.
Monitoring metabolism of synthetic cannabinoid 4F-MDMB-BINACA via high-resolution mass spectrometry assessed in cultured hepatoma cell line, fungus, adb butinaca liver microsomes and confirmed using urine samples The threshold for fatal overdose of combined use of SCRAs and ethanol can be estimated as a little ng/mL (0.37–4.1 ng/mL according to the reported cases) of SCRA and 1.5–2.5 g/L of ethanol. The reported cases and reviews of the scientific literature suggest a possible synergistic effect between SCRAs and ethanol, because their combined use clearly increases their toxicity. The victim died due to severe necrotizing pancreatitis and acute kidney injury evolving into multi-organ failure 11 days after hospital admission . Studies have found no unequivocal synergistic effect between THC and ethanol at low or moderate ethanol doses [29, 30], but no data on high doses of ethanol are available. Given that THC and ethanol act on the same receptors, data on their simultaneous use may yield important insights in this regard.
Fungus C. elegans
Methyl (2S)-2-([1-(4-fluorobutyl)-1H-indazole-3-carbonyl]amino)-3,3-dimethylbutanoate (4F-MDMB-BINACA, 4F-MDMB-BUTINACA or 4F-ADB), found in numerous SCB product seizures, has been reported by various law enforcement since 2018 . However, most of the SCBs are full agonists at CB1 and CB2 receptors, having a higher risk of undesirable side effects when compared to THC which is a partial agonist . Synthetic cannabinoids (SCBs) are agonists at cannabinoid receptor type 1 (CB1) and type 2 (CB2), where they elicit their main effect


A 30-min period, beginning when maximal depression of locomotor activity first appeared as a function of dose, was used for analysis of dose-response data and calculation of ED50 values. During test sessions, both levers were active, such that ten consecutive responses on either lever led to adb butinaca reinforcement. The substitution tests occurred only if the rats had achieved 85% injection-appropriate responding on the two prior training sessions.
The locomotor activity assay was used to identify approximate time courses and dose ranges of psychoactive effects, which is useful for identifying parameters for drug discrimination experiments and are also predictive of the time course of the psychoactive effects in human users. The purpose of the present study was to assess the abuse liability of 5F-MDMB-PINACA, MDMB-CHIMICA, MDMB-FUBINACA, ADB-FUBINACA, and AMB-FUBINACA. Since there is currently no robust measure of the reinforcing/rewarding effects of cannabinoids, drug discrimination is currently the best model for assessing abuse liability of cannabinoids. The findings produce an apparent paradox, since CPP and self-administration predict with high reliability the likelihood that a compound will be abused by humans, and cannabinoids are well-known to produce active drug-seeking in human