Sixteen healthy subjects participated in the study. Eight subjects (one female and seven males) self-administrated JWH-122 and eight subjects (three females and five males) self-administrated JWH-210. Participants were recreative drug users and had used cannabis and SCs at least once in their lifetimes without experiencing serious adverse reactions. Exclusion criteria were history of any serious medical or mental disorder including drug dependence (except for nicotine), use of chronic medication, and serious adverse reactions with cannabis and/or SCs. Subjects were recruited through word-of-mouth and snowball sampling via the nongovernmental Organization Energy Control (ABD). The study protocol was submitted and approved by the Clinical Research Ethics Committee of our center, Germans Trias i Pujol University Hospital (CEI HUGTiP, Barcelona, Spain; ref. PI-18-267), and was conducted according to the Declaration of Helsinki recommendations. All the participants were correctly and fully informed, both orally and in writing, of the purpose, methods, and means of the study. All the subjects agreed to participate in the study and signed informed consent prior to inclusion. Participants received monetary compensation for their participation.

The study design was naturalistic, prospective, and observational, with minimal intervention. The self-selected dose of JWH-122 or JWH-210 was mixed with 1 g tobacco and prepared as a joint. The participants had a maximal time of 5 min to smoke the joint following the subject usual habits of consumption (3–4.5 min, 10–11 inhalations). The mouth of the participants was washed with plain water to reduce contamination that could interfere with OF sampling (de Castro et al., 2014). All the doses that were self-administrated were also self-selected by each participant based presumably on their previous experience. Subjects brought their powder of SCs to the testing site themselves, which they had obtained from an unknown source. Although no information was available about the synthesis of the drug, those samples were tested by Energy Control, a harm reduction organization that provides a Drug Checking Service for users. The JWH-122 and JWH-201 contents were analyzed with gas chromatography associated with mass spectrometry (GC/MS) and showed that the substance purity was more than 95% with no toxic adulterants. The absence of the most common drugs of abuse including cocaine, MDMA, amphetamine, methamphetamine, 2C-B, other phenethylamines, heroin, LSD, DMT, other tryptamines, ketamine, psilocybin, salvinorin A, natural, SCs, and most of the NPS was analytically confirmed (Grifell et al., 2017; Graziano et al., 2019). The dose of JWH-122 and JWH-210 was selected after reviewing the literature and drug users fora (Hermanns-Clausen et al., 2013; Tournebize et al., 2017). Similar doses were reported in JWH-122 and JWH-210 users by Energy Control, which recommends subjects to take from 1 mg JWH-122 and 2–3 mg JWH-210 to avoid possible health risks.

The mean JWH-122 dose was 1 mg (all subjects self-administrated 1 mg, n = 8) and the mean JWH-210 dose was 2.25 mg (one male and one female self-administrated a 3 mg dose, and four males and two females self-administrated 2 mg).

All participants underwent a general medical examination and a psychiatric evaluation prior to the study sessions. They received training to fill the questionnaires and follow the procedures employed in the study. Sessions took place at a private club with ambient music, and participants could talk, read, or play table games and interact during the sessions, but not during the evaluation time. Sessions were planned on two different days, each day for one of the two groups of volunteers per substance. On the day of the session, subjects were admitted to the selected recreational venue and they were questioned about any event that could impede their participation. They were asked to refrain from taking drugs two days prior to the session, and alcohol concentrations in expired air were measured before the beginning of the sessions. Assessments were performed at baseline (before dose) and at 10, 20, and 40 min and 1, 2, 3, and 4 h after self-administration. Urine spot samples were collected prior to the administration, to exclude substance drug use (benzodiazepines, barbiturates, morphine, cocaine, amphetamines, methamphetamines, MDMA, marijuana, and phencyclidine) with One Step Rapid Test 10 Test Drug Screen (GIMA, Gessate, Milan, Italy). At baseline, no check for recent SC’s use was performed because there are no rapid tests for SC detection available. However, an OF sample was collected at baseline (before administration) in which no traces of JWH-210, JWH-122, or other SCs were detected. Tobacco users were asked to refrain from smoking 2 h before the beginning of the study session until the end of the session. Adverse events were assessed during the study sessions and were reported within 24 h after the self-administration session (24 h by a phone call).

Noninvasive systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were determined with an Omron® monitor at baseline and at 10, 20, and 40 min and 1, 2, 3, and 4 h after administration. The oral temperature was measured at the same time.

Subjective effects were measured at different moments during the session, using a set of visual analog scales (VASs), the 49-item Addiction Research Center Inventory (ARCI) form, and the Evaluation of Subjective Effects of Substances with Abuse Potential questionnaire (VESSPA-SP).

VAS from “not at all” to “extremely” were used to rate some items such as “intensity,” “high,” “good effects,” “bad effects,” “hunger,” “drowsiness,” “dizziness,” “confusion,” “nausea,” “vomits,” “anxiety,” “aggressiveness,” “hallucinations-seeing of lights or spots,” “hallucinations-hearing sounds or voices,” and “hallucinations-seeing animals, things, insects or people” (Papaseit et al., 2018; Papaseit et al., 2020).

The Spanish validated version of the short-form ARCI is a true/false 49-item questionnaire, an instrument for the determination of subjective drug effects (Lamas et al., 1994). It includes five subscales related to drug sedation (pentobarbital-chlorpromazine-alcohol group, PCAG), euphoria (morphine-benzedrine group, MBG), dysphoria and somatic symptoms (lysergic acid diethylamide group, LSD), intellectual efficiency and energy (benzedrine group, BG), and d-amphetamine-like effects (amphetamine, A).

The VESSPA is a questionnaire measuring the changes in subjective effects caused by different drugs, including stimulants and psychedelics. It includes six subscales: sedation (S), psychosomatic anxiety (ANX), changes in perception (CP), pleasure and sociability (SOC), activity and energy (ACT), and psychotic symptoms (PS) (González et al., 2015).

The VASs were administered at baseline and at 10, 20, and 40 min and 1, 2, 3, and 4 h after drug administration. ARCI and VESSPA forms were completed at baseline and at 1, 2, 3, and 4 h after drug administration.

OF was collected with Salivette® tubes at baseline and at 10, 20, and 40 min and 1, 2, 3, and 4 h after self-administration.

Samples were then centrifuged and frozen at −20°C until analysis. JWH-210 and JWH-122 were quantified by a modified and validated liquid chromatography-mass spectrometry method (LC-MS/MS) (Pellegrini et al., 2020).

Physiological (SBP, DBP, HR, and cutaneous T) and subjective (VAS, ARCI, and VESSPA) variables were compared to baseline. Peak effects (Emax) were determined and the area under the curve of the effects (AUC0−4 h) was calculated using the trapezoidal rule by the Pharmacokinetic Functions for Microsoft Excel (Joel Usansky, Atul Desai, and Diane Tang-Liu, Department of Pharmacokinetics and Drug Metabolism, Allergan, Irvine, CA, United States).

For statistical analysis, four consecutive strategies were performed. Firstly, since subjects selected two different JWH-210 doses (2 and 3 mg, see Study Design and Treatments), a one-way analysis of variance (ANOVA) test was conducted to evidence the possible influence of JWH-210 dose on the different variables evaluated. The results showed no statistically significant differences between the two doses. Hence, the presented statistical analysis was performed considering data as just one dose. Secondly, Student’s t-test for unpaired samples was performed to compare Emax and AUC0−4 h of JHW-122 and JWH-210 of all parameters calculated. Differences in time to reach peak effects (Tmax) between JHW-122 and JWH-210 were assessed using a nonparametric test (Wilcoxon test). Thirdly, a GLM two-way repeated-measures ANOVA with drug (JWH-122 and JWH-201) and time (baseline, 10, 20, and 40 min, and 1, 2, 3, and 4 h) as factors was used to compare the TC of effects between JHW-122 and JWH-210. If significant differences were detected in drug and time factor, a sequential Bonferroni correction was applied to correct for multiple comparisons. Fourthly, since no control group was included, Dunnett’s multiple comparison post hoc test was conducted to evaluate time effects for each SC (JWH-122 and JWH-2010) comparing the different time points with baseline values (comparing times 0–10, 0–20, and 0–40 min and 0–1, 0–2, 0–3, and 0–4 h). Statistical analyses were performed using PAWS Statistics version 18 (SPSS Inc., Chicago, IL, United States). Statistical significance was defined as p < 0.05.

For OF data, only a descriptive analysis was presented showing main pharmacokinetics data, e.g., maximum concentration (Cmax), the time needed to reach the maximum concentration (Tmax), and AUC0–4. These descriptive parameters were calculated using the Pharmacokinetic Functions for Microsoft Excel (Joel Usansky, Atul Desai, and Diane Tang-Liu, Department of Pharmacokinetics and Drug Metabolism, Allergan, Irvine, CA, United States). No statistical analysis was performed between OF concentrations measured comparing both SCs.

Sixteen polydrug recreational users who reported previous multiple experiences with cannabis and having used SCs at least once in their lives were recruited for the study (4 females and 12 males). Eight subjects were self-administrated by inhalation 1 mg of JWH-122 (seven males and one female). They had a mean age of 30 ± 6 years (range: 23–41 years), weighing 72.95 ± 11.22 kg (range: 60–96 kg), and their mean body mass index (BMI) was 24.16 ± 4.09 kg/m² (range: 19.59 ± 32.45 kg/m²). Six participants were current tobacco smokers.

Eight subjects self-administrated JWH-210 by inhalation. One male and one female self-administrated a 3 mg dose, and four males and two females self-administrated 2 mg. They had a mean age of 31 ± 7 years (range: 22–41 years), weighing 69.63 ± 13.38 kg (range: 54–93 kg), and their mean BMI was 23.26 ± 2.49 kg/m² (range: 18.29–26.04 kg/m²). Five participants were current tobacco smokers (Table 1).

JWH-122 and JWH-210 effects on physiological variables are presented in Table 2 and Figure 1.

Self-inhalation of JWH-122 and JWH-210 produced changes in the physiological variables taken into consideration. Compared to baseline, JWH-122 self-inhalation produced statistically significant increases in SBP, DBP, and HR and JWH-210 self-administration only increased HR. The maximal effects were observed at 10–20 min following administration. No statistically significant differences were found between JWH-122 and JWH-210 in terms of Emax, AUC0–4 h, or TC points, except for the body temperature (Tº) at 1 and 4 h.

JWH-122 and JWH-210 effects on subjective variables are presented in Table 2 and Figure 1.

Self-inhalation of JWH-122 and JWH-210 induced some changes in subjective effects.

JWH-122 self-inhalation increased VAS “intensity,” “high” and “good effects,” “hunger,” “somnolence,” “dizziness,” “confusion,” and “anxiety,” and JWH-210 increased VAS “intensity” and “high” and “good effects.” For both SCs, maximal VAS effects were mostly observed 20 min after intake. Compared to baseline, statistically significant increases were detected on VAS “intensity,” “high effects,” and “hunger” for JWH-210 only. When comparing JWH-122 and JWH-210, no statistically significant differences were found for Emax or AUC0–4 h. For TC, differences between SCs were only detected for VAS “hunger” at 4 h.

Self-inhalation of JWH-122 or JWH-210 produced slight changes in the majority of ARCI questionnaire subscales, with more marked increases in the subscales sedation (PCAG: pentobarbital chlorpromazine-alcohol group), euphoria (MBG), and amphetamine (A). Compared to baseline, statistically significant increases were found for MBG and A following self-inhalation of JWH-210.

Compared to baseline, JWH-122 and JWH-210 induced nonsignificant increases in the VESSPA-SP questionnaire. When comparing JWH-122 and JWH-210, no statistically significant differences were found for Emax or AUC0–4 h. For TC, differences between SCs were only detected for “ANX” subscale at 1 h.

All the selected doses were well tolerated with no relevant adverse events during the study session. Within 24 h after the self-administration, one subject who self-administrated JWH-122 reported faintness and three subjects who self-administrated 2 mg of JWH-210 reported 1) hypotension, 2) headache, dizziness, and vomit, and 3) self-limited mild stabbing chest pain, respectively. All resolved spontaneously, and the participants did not need medication or medical assistance.

JWH-122 and JWH-210 OF concentration profiles over time (no data available from one subject consuming JWH 210) are shown in Figure 2. JWH-122 OF concentration reached a peak 20 min after administration with a mean maximum concentration (Cmax) of 3.88 ng/ml (SD ± 1.23), decreased to a mean value of 0.62 ng/ml at 1 h, and was not detected after 3 h. Mean AUC0–4 h was 2.60 ng/mlh (SD ± 0.81). Similarly, JWH-210 OF concentration peaked 20 min after inhalation and was not detected after 3 h. JWH-210 Cmax was 22.54 ng/ml (SD ± 19.02) 20 min after intake and dropped to a mean value of 4.30 ng/ml at 1 h. AUC0–4 h mean value was 17.18 ng/ml h (SD ± 12.51).