Determination of cannabinoids in urine, oral fluid and hair samples after repeated intake of CBD-rich cannabis by smoking

Recent advances in the chromatographic analysis of endocannabinoids and phytocannabinoids in biological samples

Endocannabinoid system, including endocannabinoid neurotransmitters (eCBs), has gained much attention over the last years due to its involvement with the pathophysiology of diseases and the potential use of Cannabis sativa (marijuana). The identification of eCBs and phytocannabinoids in biological samples for forensic, clinical, or therapeutic drug monitoring purposes constitutes a still significant challenge. In this scoping review, the recent advantages, and limitations of the eCBs and phytocannabinoids quantification in biological samples are described. Published studies from 2018-2023 were searched in 8 databases, and after screening and exclusions, the selected 38 articles had their data tabulated, summarized, and analyzed. The main characteristics of the eCBs and phytocannabinoids analyzed and the potential use of each biological sample were described, indicating gaps in the literature that still need to be explored. Well-established and innovative sample preparation protocols, and chromatographic separations, such as GC, HPLC, and UHPLC, are reviewed highlighting their respective advantages, drawbacks, and challenges. Lastly, future approaches, challenges, and tendencies in the quantification analysis of cannabinoids are discussed.

An initial exploration of machine learning for establishing associations between genetic markers and THC levels in Cannabis sativa samples

Cannabis sativa, a globally commercialized plant used for medicinal, food, fiber production, and recreation, necessitates effective identification to distinguish legal and illegal varieties in forensic contexts. This research utilizes multivariate statistical models and Machine Learning approaches to establish correlations between specific genotypes and tetrahydrocannabinol (Δ9-THC) content (%) in C. sativa samples. 132 cannabis leaves samples were obtained from legal growers in Piedmont, Italy, and illegal drug seizures in Turin. Samples were genetically profiled using a 13-loci STR multiplex and their Δ9-THC content was detected through quantitative GC-MS analysis. This study aims to assess the use of supervised classification modelling on genetic data to distinguish cannabis samples into legal and illegal categories, revealing distinct clusters characterized by unique allele profiles and THC content. t-distributed Stochastic Neighbor Embedding (t-SNE), Random Forest (RF) and Partial Least Squares Regression (PLS-R) were executed for the machine learning modelling. All the tested models resulted effective discriminating between legal samples and illegal. Although further validation is necessary, this study presents a novel forensic investigative approach, potentially aiding law enforcement in significant marijuana seizures or tracking illicit drug trafficking routes.

Progress in the analysis of phytocannabinoids by HPLC and UPLC (or UHPLC) during 2020-2023

INTRODUCTION

Organic molecules that bind to cannabinoid receptors are known as cannabinoids. These molecules possess pharmacological properties similar to those produced by Cannabis sativa L. High-performance liquid chromatography (HPLC) and ultra-performance liquid chromatography (UPLC, also known as ultra-high-performance liquid chromatography, UHPLC) have become the most widely used analytical tools for detection and quantification of phytocannabinoids in various matrices. HPLC and UPLC (or UHPLC) are usually coupled to an ultraviolet (UV), photodiode array (PDA), or mass spectrometric (MS) detector.

OBJECTIVE

To critically appraise the literature on the application of HPLC and UPLC (or UHPLC) methods for the analysis of phytocannabinoids published from January 2020 to December 2023.

METHODOLOGY

An extensive literature search was conducted using Web of Science, PubMed, and Google Scholar and published materials including relevant books. In various combinations, using cannabinoid in all combinations, cannabis, hemp, hashish, C. sativa, marijuana, analysis, HPLC, UHPLC, UPLC, and quantitative, qualitative, and quality control were used as the keywords for the literature search.

RESULTS

Several HPLC- and UPLC (or UHPLC)-based methods for the analysis of phytocannabinoids were reported. While simple HPLC-UV or HPLC-PDA-based methods were common, the use of HPLC-MS, HPLC-MS/MS, UPLC (or UHPLC)-PDA, UPLC (or UHPLC)-MS, and UPLC (or UHPLC)-MS/MS was also reported. Applications of mathematical and computational models for optimization of protocols were noted. Pre-analyses included various environmentally friendly extraction protocols.

CONCLUSION

During the last 4 years, HPLC and UPLC (or UHPLC) remained the main analytical tools for phytocannabinoid analysis in different matrices.

Determination of Δ9-tetrahydrocannabinol, 11-nor-carboxy-Δ9-tetrahydrocannabinol and cannabidiol in human plasma and urine after a commercial cannabidiol oil product intake

PURPOSE

Cannabidiol (CBD) products are widely used for pain relief, sleep improvement, management of seizures etc. Although the concentrations of Δ9-tetrahydrocannabinol (Δ9-THC) in these products are low (≤0.3% w/w), it is important to investigate if its presence and/or that of its metabolite 11-nor-carboxy-Δ9-THC, is traceable in plasma and urine samples of individuals who take CBD oil products.

METHODS

A sensitive GC/MS method for the determination of Δ9-THC, 11-nor-carboxy-Δ9-THC and CBD in plasma and urine samples was developed and validated. The sample preparation procedure included protein precipitation for plasma samples and hydrolysis for urine samples, solid-phase extraction and finally derivatization with N,O-bis(trimethylsilyl)trifluoroacetamide) with 1% trimethylchlorosilane.

RESULTS

For all analytes, the LOD and LOQ were 0.06 and 0.20 ng/mL, respectively. The calibration curves were linear (R2 ≥ 0.992), and absolute recoveries were ≥91.7%. Accuracy and precision were within the accepted range. From the analysis of biologic samples of 10 human participants who were taking CBD oil, it was realized that Δ9-THC was not detected in urine, while 11-nor-carboxy-Δ9-THC (0.69-23.06 ng/mL) and CBD (0.29-96.78 ng/mL) were found in all urine samples. Regarding plasma samples, Δ9-THC (0.21-0.62 ng/mL) was detected in 10, 11-nor-carboxy-Δ9-THC (0.20-2.44 ng/mL) in 35, while CBD (0.20-1.58 ng/mL) in 25 out of 38 samples, respectively.

CONCLUSION

The results showed that Δ9-THC is likely to be found in plasma although at low concentrations. In addition, the detection of 11-nor-carboxy-Δ9-THC in both urine and plasma samples raises questions and concerns for the proper interpretation of toxicological results, especially considering Greece's zero tolerance law applied in DUID and workplace cases.

Coupling Miniaturized Stir Bar Sorptive Dispersive Microextraction to Needle-Based Electrospray Ionization Emitters for Mass Spectrometry: Determination of Tetrahydrocannabinol in Human Saliva as a Proof of Concept

Direct coupling of sample preparation with mass spectrometry (MS) can speed up analysis, enabling faster decision-making. In such combinations, where the analysis time is mainly defined by the extraction procedure, magnetic dispersive solid-phase extraction emerges as a relevant technique because of its rapid workflow. The dispersion and retrieval of the magnetic sorbent are typically uncoupled stages, thus reducing the potential simplicity. Stir bar sorptive dispersive microextraction (SBSDME) is a novel technique that integrates both stages into a single device. Its miniaturization (mSBSDME) makes it more portable and compatible with low-availability samples. This article reports the direct combination of mSBSDME and MS using a needle-based electrospray ionization (NESI) emitter as the interface. This combination is applied to determine tetrahydrocannabinol in saliva samples, a relevant societal problem if the global consumption rates of cannabis are considered. The coupling requires only the transference of the magnet (containing the sorbent and the isolated analyte) from the mSBSDME to the hub of a hypodermic needle, where the online elution occurs. The application of 5 kV on the needle forms an electrospray on its tip, transferring the ionized analyte to the MS inlet. The excellent performance of mSBSDME-NESI-MS/MS relies on the sensitivity (limits of detection as low as 2.25 ng mL-1), the precision (relative standard deviation lower than 15%), and the accuracy (relative recoveries ranged from 87 to 127%) obtained. According to the results, the mSBSDME-NESI-MS/MS technique promises faster and more efficient chemical analysis in MS-based applications.

Identification and quantification of both isomers of hexahydrocannabinol, (9R)-hexahydrocannabinol and (9S)-hexahydrocannabinol, in three different matrices by mass spectrometry

CONTEXT

Hexahydrocannabinol (HHC), a compound derived from synthetic production using cannabidiol (CBD) or delta-9-tetrahydrocannabinol (Δ9 -THC), has gained recent attention due to its presence in seized materials across Europe. Sold legally in various forms, HHC poses potential health risks, particularly as a legal alternative to THC in some countries. Despite its historical description in the 1940s, limited toxicology data, pharmacological understanding, and analytical methods for HHC exist.

METHOD

This study proposes analytical techniques using mass spectrometry to detect, identify, and quantify (9R)-HHC and (9S)-HHC, concurrently with THC and CBD in various matrices, including oral fluid, whole blood, and seized material. Three distinct methods were employed for different matrices: GC/MS for seized material, GC/MS/MS for whole blood, and UHPLC/MS/MS for oral fluid. Methods were validated qualitatively for oral fluid with a FLOQSwab® device and quantitatively in whole blood and seized material according to Peters et al's recommendations and ICH guidelines.

RESULTS

Validated methods were considered reliable in detecting and quantifying HHC isomers in terms of repeatability, reproducibility, and linearity with r2 systematically >0.992. These methods were applied to authentic cases, including seized materials and biological samples from traffic control (whole blood and oral fluid). In seized materials, (9R)-HHC levels ranged from 2.09% to 8.85% and (9R)-HHC/(9S)-HHC ratios varied from 1.36 to 2.68. In whole blood sample, (9R)-HHC and (9S)-HHC concentrations were, respectively, 2.38 and 1.39 ng/mL. For all analyzed samples, cannabinoids such as THC and CBD were also detected.

CONCLUSION

This research contributes analytical insights into differentiating and simultaneously analyzing (9R)-HHC and (9S)-HHC, using widely applicable mass spectrometric methods. The study emphasizes the need for vigilance among toxicologists, as new semisynthetic cannabinoids continue to emerge in Europe, with potential health implications. The findings underscore the importance of reliable analytical methods for monitoring these compounds in forensic and clinical settings.

External hair contamination from cannabis and "light cannabis" delivered by smoking and vaping: An in vitro study

External contamination of hair by cannabis smoking requires a careful evaluation in forensic toxicology. Medical and recreational cannabis are increasingly consumed by e-cigarettes, which give rise to side-stream vapor. Moreover, products containing low Δ9-tetrahydrocannabinol (Δ9-THC) and rich in cannabidiol (CBD) started spreading legally. The goal of the present study was to assess whether hair analysis could allow to distinguish the type of delivered product, with low or high Δ9-THC, and the delivering mode, by smoking or vaping. Contamination of blank hair was mimicked by in vitro exposure to low- (0.4%) and high-Δ9-THC (9.7%) products delivered by smoking and vaping within a small confined system. Cannabis vaping extracts were prepared to deliver identical target Δ9-THC doses. Eighty samples were analyzed by ultrahigh-performance liquid chromatography mass spectrometry and quantified for Δ9-THC and CBD. After contamination by cannabis smoking, THC levels were in line with past in vitro and in vivo studies. Samples exposed to cannabis (169.30 ng/mg) showed significantly higher Δ9-THC than hair exposed to "light cannabis" (35.54 ng/mg), and the opposite was seen for the CBD/Δ9-THC ratio. Hair contaminated by vaping or smoking did not show a statistically different Δ9-THC content. Under our in vitro conditions, hair analysis might allow to discriminate whether external contamination is determined by products containing low or high Δ9-THC, but not the delivering mode. More research is needed in real-life conditions, to see whether the same also applies to the interpretation of forensic casework.

Factors influencing the in situ formation of Δ9-THC from cannabidiol during GC-MS analysis

Gas chromatography-mass spectrometry (GC-MS) is widely used for the identification of cannabinoids in seized plant material. Conditions used for instrumental analysis should maximize decarboxylation, while minimizing the in situ production of Δ9-THC inside the GC inlet. In this study, decarboxylation of the acidic Δ9-THC precursor and in situ degradation of cannabidiol (CBD) were investigated using seven commercial GC liners with different deactivation chemistries and geometries. While the inlet temperature was previously optimized at 250°C in a previously validated assay, we systematically examined the temperature-dependent decarboxylation of tetrahydrocannabinolic acid-A (Δ9-THCA-A) and cyclization of CBD between 230°C and 310°C using different liners using favorable and unfavorable conditions. Significant differences in decarboxylation rate and CBD cyclization were observed between different liner types. While no temperature-dependent differences in decarboxylation rate were observed within liner type, liner-dependent differences were observed (α = 0.05), particularly between those with different geometry. In contrast, temperature and liner-dependent differences were observed for in situ formation of Δ9-THC (α = 0.05). This was influenced by liner geometry and to a smaller extent by surface deactivation. Effects were exacerbated with liner usage. While significant differences were observed using new and used GC liners, differences between liners of the same type but different lot numbers were not observed. Inter-instrument differences using the same liner were also evaluated and had minimal effect. Liner- and temperature-dependent effects were also confirmed using more than 20 cannabis plant extracts. Careful selection of liner, inlet conditions, and regular preventive maintenance can mitigate the risks associated with in situ formation Δ9-THC from CBD.

Health status outcome among cannabis addicts after treatment of addiction

The abuse of Cannabis is a widespread issue in the Asir region. It has a lot of legal and occupational repercussions. The purpose of this study was to evaluate the health status of cannabis addicts at admission and after treatment using body mass index, glycemic status, liver function, renal function, and oxidative stress. A cross-sectional study was conducted with 120 participants. The study was conducted at Al Amal Hospital for Mental Health in Asir region of Saudi Arabia, with 100 hospitalized patients receiving addiction treatment and 20 healthy volunteers. The participants were divided into two groups: group I, the control group, and group II, the cannabis addicts. The socio-demographic data were gathered. The level of cannabis in the urine and the CWAS [Cannabis Withdrawal Assessment Scale] were determined. In addition, the Body Mass Index [BMI], vital signs [temperature, heart rate, systolic blood pressure, diastolic blood pressure, and respiratory rate], serum levels of albumin, total bilirubin, direct bilirubin, AST, ALT, and ALP, urea, creatinine, Thiobarbituric acid-reactive substances [TBARS], superoxide dismutase [SOD], reduced glutathione [GSH], and catalase [CAT] were analyzed on the first day of admission and after treatment. According to the results, there was no significant change in the body mass index. The vital signs in the cannabis user group were significantly lower than the corresponding admission values. Regarding renal function tests such as urea and creatinine, we found that after treatment, the mean urea and creatinine values in the cannabis user group did not differ significantly from the corresponding admission values. However, after treatment, the mean values of fasting blood glucose levels in the cannabis user group were significantly lower than at admission. Also, the mean values of liver function tests such as albumin, total bilirubin, direct bilirubin, AST, ALT, and ALP in the cannabis user group were significantly lower than the corresponding admission values after treatment. In assessing the antioxidant system, we found that the mean values of TBARS, SOD, GSH, and CAT in the cannabis user group did not differ significantly from the corresponding admission values after treatment. The current findings have revealed that cannabis addiction harms the various body systems and has significant implications for the addict's state of health. The values of oxidative stress biomarkers did not change in this study, but other measured parameters improved after treatment.

[Cannabidiol (CBD): Analytical and toxicological aspects]

Cannabidiol (CBD) is a phytocannabinoid present in cannabis, obtained either by extraction from the plant or by synthesis. The latter has the advantage of being pure and contains few impurities, unlike CBD of plant origin. It is used by inhalation, ingestion or skin application. In France, the law stipulates that specialties containing CBD may contain up to 0.3% of tetrahydrocannabinol (THC), the psychoactive principle of cannabis. From an analytical point of view, it is therefore important to be able to quantify the two compounds as well as their metabolites in the various matrices that can be used clinically or forensically, in particular saliva and blood. The transformation of CBD into THC, which has long been suggested, appears to be an analytical artifact under certain conditions. CBD is not without toxicity, whether acute or chronic, as seems to attest to the serious adverse effects recorded by pharmacovigilance during the experiment currently being conducted in France by the Agence Nationale de Sécurité du Médicament et des Produits de Santé. Although CBD does not seem to modify driving abilities, driving a vehicle after consuming CBD containing up to 0.3% THC, and sometimes much more in products bought on the internet, can lead to a positive result in screening and confirmation tests by law enforcement agencies, whether salivary or blood tests, and therefore lead to a legal sanction.

Conversion of water-soluble CBD to ∆9-THC in synthetic gastric fluid-An unlikely cause of positive drug tests

Cannabidiol (CBD) has been shown to convert to ∆9-tetrahydrocannabinol (∆9-THC) in acidic environments, raising a concern of conversion when exposed to gastric fluid after consumption. Using synthetic gastric fluid (SGF), it has been demonstrated that the conversion requires surfactants, such as sodium dodecyl sulfate (SDS), due to limited solubility of CBD. Recently, water-compatible nanoemulsions of CBD have been prepared as a means of fortifying beverages and water-based foods with CBD. Since these emulsions contain surfactants as part of their formulation, it is possible that these preparations might enhance the production of ∆9-THC even in the absence of added surfactants. Three THC-free CBD products, an oil, an anhydrous powder and a water-soluble formulation, were incubated for 3 h in SGF without SDS. The water-soluble CBD product produced a dispersion, while the powder and the oil did not mix with the SGF. No THC was detected with the CBD oil (<0.0006% conversion), and up to 0.063% and 0.0045% conversion to ∆9-THC was observed with the water-soluble CBD and the CBD powder, respectively. No formation of ∆8-THC was observed. In comparison, when the nano-formulated CBD was incubated in SGF with 1% SDS, 33-36% conversion to ∆9-THC was observed. Even though the rate of conversion with the water-soluble CBD was at least 100-fold higher compared to the CBD oil, it was still smaller than ∆9-THC levels reported in CBD products labeled "THC-free" or "<0.3% THC" based on the Agricultural Improvement Act of 2018 (the Farm Bill). Assuming a daily CBD dose of around 30 mg/day, it is unlikely that conversion of CBD to ∆9-THC could produce a positive urinary drug test for 11-Nor-9-carboxy-∆9-THC (15 ng/mL cut-off).

Analysis of Cannabinoids in Biological Specimens: An Update

Cannabinoids are still the most consumed drugs of abuse worldwide. Despite being considered less harmful to human health, particularly if compared with opiates or cocaine, cannabis consumption has important medico-legal and public health consequences. For this reason, the development and optimization of sensitive analytical methods that allow the determination of these compounds in different biological specimens is important, involving relevant efforts from laboratories. This paper will discuss cannabis consumption; toxicokinetics, the most detected compounds in biological samples; and characteristics of the latter. In addition, a comprehensive review of extraction methods and analytical tools available for cannabinoid detection in selected biological specimens will be reviewed. Important issues such as pitfalls and cut-off values will be considered.

Determination of cannabinoids content in light cannabis inflorescences sold in France

In the last 2 years, the number of shops selling CBD-rich THC-deprived cannabis flowers (CrTd) has increased considerably in France as in many European countries. The objective of this study was to determine the actual composition of the samples sold in these stores and to discuss regulatory consequences that may affect users. Samples were provided from shops in the region Provence-Alpes Cote d'Azur (PACA), France. Pictures of the samples were taken before they were weighed then crushed. Twenty milligrams were diluted in 10 ml heptane ethyl acetate (7:1; v:v) for analysis by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method was validated according to SWGTOX guidelines for the quantification of cannabidiol (CBD), delta-9-tetrahydrocannabinol (THC) and cannabinol (CBN). Thirty-nine samples obtained between November 2021 and January 2022 in the PACA region were analyzed in this study. Mean content was 0.32% (0.03%-0.77%; STDV = 0.17%; n = 39) for THC, 2.23% (0.01%-5.97%; STDV = 1.29%; n = 39) for CBD and 0.01% (0.004%-0.025%; STDV = 0.01%; n = 19) for CBN. THC content over the threshold defined by the European legislation (>0.3%) was found in 18 of the 39 samples analyzed together with a CBD content <1% in nine samples (23%). None of the products analyzed had health risk messages on the packaging. The consumption of these products may lead to the presence of THC in biological fluids, which can be detected by screening. Users may then find themselves in breach of the law particularly when driving. Consumers should therefore be informed both about the actual composition of these products and about the legal and health risks they run.

Bridging Disciplines: Applications of Forensic Science and Industrial Hemp

Forensic laboratories are required to have analytical tools to confidently differentiate illegal substances such as marijuana from legal products (i.e., industrial hemp). The Achilles heel of industrial hemp is its association with marijuana. Industrial hemp from the Cannabis sativa L. plant is reported to be one of the strongest natural multipurpose fibers on earth. The Cannabis plant is a vigorous annual crop broadly separated into two classes: industrial hemp and marijuana. Up until the eighteenth century, hemp was one of the major fibers in the United States. The decline of its cultivation and applications is largely due to burgeoning manufacture of synthetic fibers. Traditional composite materials such as concrete, fiberglass insulation, and lumber are environmentally unfavorable. Industrial hemp exhibits environmental sustainability, low maintenance, and high local and national economic impacts. The 2018 Farm Bill made way for the legalization of hemp by categorizing it as an ordinary agricultural commodity. Unlike marijuana, hemp contains less than 0.3% of the cannabinoid, Δ9-tetrahydrocannabinol, the psychoactive compound which gives users psychotropic effects and confers illegality in some locations. On the other hand, industrial hemp contains cannabidiol found in the resinous flower of Cannabis and is purported to have multiple advantageous uses. There is a paucity of investigations of the identity, microbial diversity, and biochemical characterizations of industrial hemp. This review provides background on important topics regarding hemp and the quantification of total tetrahydrocannabinol in hemp products. It will also serve as an overview of emergent microbiological studies regarding hemp inflorescences. Further, we examine challenges in using forensic analytical methodologies tasked to distinguish legal fiber-type material from illegal drug-types.

Partitioning of phytocannabinoids between faeces and water - Implications for wastewater-based epidemiology

Evaluating consumption estimates for lipophilic drugs in wastewater has proven to be a challenge. A common feature for these compounds is that they are excreted in faeces and in conjugated form in urine. Limited research with no obvious experimental evidence has been conducted to investigate the degree to which faecal-bound chemical markers contribute towards mass loads in wastewater. Cannabis chemical markers, known as phytocannabinoids, have been suggested in literature to fall into this category. In this study, cannabis users (n = 9) and non-cannabis users (n = 5) were recruited and provided faecal and urine samples after using the substance. The common chemical markers of cannabis consumption, 11-nor-9-carboxy-Δ⁹-tetrahydrocannabinol (THC-COOH), 11-hydroxy-Δ⁹-tetrahydrocannabinol (THC-OH), Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD), were investigated. An extraction method was developed for the cannabis chemical markers in faecal matter and urine and analysis was performed by liquid chromatography-mass spectrometry. Participant samples were used to establish adsorption and desorption dissolution kinetics models and to assess the equilibrium between faeces and water for these compounds. Equilibration between phases were found to be fast (<5 min). THC-COOH, which is the primary metabolite used in wastewater studies, partitioned ~40% in water while the less polar metabolite and CBD remained largely associated with the particulate fraction. Faecal loads of both cannabis users and non-users affected the total measured amounts of cannabinoids in the aqueous phase. The implications for wastewater monitoring of lipophilic substances are discussed.

Alternative matrices in forensic toxicology: a critical review

Purpose

The use of alternative matrices in toxicological analyses has been on the rise in clinical and forensic settings. Specimens alternative to blood and urine are useful in providing additional information regarding drug exposure and analytical benefits. The goal of this paper is to present a critical review on the most recent literature regarding the application of six common alternative matrices, i.e., oral fluid, hair, sweat, meconium, breast milk and vitreous humor in forensic toxicology.

Methods

The recent literature have been searched and reviewed for the characteristics, advantages and limitations of oral fluid, hair, sweat, meconium, breast milk and vitreous humor and its applications in the analysis of traditional drugs of abuse and novel psychoactive substances (NPS).

Results

This paper outlines the properties of six biological matrices that have been used in forensic analyses, as alternatives to whole blood and urine specimens. Each of this matrix has benefits in regards to sampling, extraction, detection window, typical drug levels and other aspects. However, theses matrices have also limitations such as limited incorporation of drugs (according to physical–chemical properties), impossibility to correlate the concentrations for effects, low levels of xenobiotics and ultimately the need for more sensitive analysis. For more traditional drugs of abuse (e.g., cocaine and amphetamines), there are already data available on the detection in alternative matrices. However, data on the determination of emerging drugs such as the NPS in alternative biological matrices are more limited.

Conclusions

Alternative biological fluids are important specimens in forensic toxicology. These matrices have been increasingly reported over the years, and this dynamic will probably continue in the future, especially considering their inherent advantages and the possibility to be used when blood or urine are unavailable. However, one should be aware that these matrices have limitations and particular properties, and the findings obtained from the analysis of these specimens may vary according to the type of matrix. As a potential perspective in forensic toxicology, the topic of alternative matrices will be continuously explored, especially emphasizing NPS.

"Light cannabis" consumption in a sample of young adults: Preliminary pharmacokinetic data and psychomotor impairment evaluation

INTRODUCTION

In 2019, the Italian Supreme Court established that hemp cannot be commercialized for human use, when the "psychotropic effect" of the product or its "offensiveness" can be demonstrated. The aim of the present study is to assess Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) blood concentrations after smoking cannabis with a low percentage of Δ9-THC, also referred as "light cannabis", and its effects on young adults' vigilance, cognitive and motor skills.

MATERIALS AND METHODS

Eighteen young adults consumed three light cannabis cigarettes containing 400 mg of inflorescences each, with a percentage of 0.41% of Δ9-THC and of 12.41% of CBD. Blood samples were collected before the experiment (t0), after each light cannabis cigarette (t1→t3), 60 (t4) and 120 (t5) minutes after the beginning of the experiment. Five performance tasks and a subjective scale were employed for measuring cognitive and psychomotor performances the day before the experiment (TT0) and after the third cigarette (TT1).

RESULTS

Mean (SD) concentrations (ng/ml) were 1.0 (0.8) in t1, 1.2 (0.9) in t2, 1.0 (0.8) in t3, 0.6 (0.4) in t4 and 0.3 (0.3) in t5 for Δ9-THC; 10.5 (10.3) in t1, 10.3 (13.2) in t2, 15.1 (14.8) in t3, 9.9 (9.2) in t4 and 5.7 (5.7) in t5 for CBD. No significant differences were observed between TT0 and TT1 for all performed psychomotor performance task. None of the subjects declared to feel "high" after the experiment.

DISCUSSION

All study participants reported that a higher number of cigarettes, corresponding in this study to 1200 mg of herbal product, could hardly be consumed by smoking in a recreational setting. Δ9-THC and CBD concentrations showed a high inter-subject variability, and the average concentrations were lower than those previously reported. Toxicological results showed a decrease of Δ9-THC and CBD after the third light cannabis cigarette, and a Δ9-THC /CBD ratio always<1 was observed. The lack of impairment observed in our participants can be interpreted as a consequence of the very low concentrations detectable in the blood.