Major Constituents of Cannabis Vape Oil Liquid, Vapor and Aerosol in California Vape Oil Cartridge Samples

GC/HRMS Analysis of E-Liquids Complements In Vivo Modeling Methods and can Help to Predict Toxicity

Tobacco smoking is a major risk factor for disease development, with the user inhaling various chemicals known to be toxic. However, many of these chemicals are absent before tobacco is "burned". Similar, detailed data have only more recently being reported for the e-cigarette with regards to chemicals present before and after the e-liquid is "vaped." Here, zebrafish were dosed with vaped e-liquids, while C57-BL/6J mice were vaped using nose-cone only administration. Preliminary assessments were made using e-liquids and GC/HRMS to identify chemical signatures that differ between unvaped/vaped and flavored/unflavored samples. Oxidative stress and inflammatory immune cell response assays were then performed using our in vivo models. Chemical signatures differed, e.g., between unvaped/vaped samples and also between unflavored/flavored e-liquids, with known chemical irritants upregulated in vaped and unvaped flavored e-liquids compared with unflavored e-liquids. However, when possible respiratory irritants were evaluated, these agents were predominantly present in only the vaped e-liquid. Both oxidative stress and inflammatory responses were induced by a menthol-flavored but not a tobacco-flavored e-liquid. Thus, chemical signatures differ between unvaped versus vaped e-liquid samples and also between unflavored versus flavored e-liquids. These flavors also likely play a significant role in the variability of e-liquid characteristics, e.g., pro-inflammatory and/or cytotoxic responses.

The paradox of the safer cigarette: understanding the pulmonary effects of electronic cigarettes

Electronic cigarette (e-cigarette) use continues to rise globally. E-cigarettes have been presented as safer alternatives to combustion cigarettes that can mitigate the harm associated with tobacco products; however, the degree to which e-cigarette use itself can lead to morbidity and mortality is not fully defined. Herein we describe how e-cigarettes function; discuss the current knowledge of the effects of e-cigarette aerosol on lung cell cytotoxicity, inflammation, antipathogen immune response, mucociliary clearance, oxidative stress, DNA damage, carcinogenesis, matrix remodelling and airway hyperresponsiveness; and summarise the impact on lung diseases, including COPD, respiratory infection, lung cancer and asthma. We highlight how the inclusion of nicotine or flavouring compounds in e-liquids can impact lung toxicity. Finally, we consider the paradox of the safer cigarette: the toxicities of e-cigarettes that can mitigate their potential to serve as a harm reduction tool in the fight against traditional cigarettes, and we summarise the research needed in this underinvestigated area.

An evaluation of the cannabinoid content of the liquid and thermal degradation analysis of cannabis-labeled vape liquids

Cannabidiol (CBD) vape pen usage has been on the rise given the changing political and scientific climate as well as the promotion of these delivery systems as a more accessible and lower-risk option for consumers. Despite being marketed as a safer way to use cannabis, CBD vape liquids are sold without restrictions or meticulous quality control procedures such as toxicological and clinical assessment, standards for product preservation, or investigative degradation analyses. Nine CBD-labeled vape liquid samples purchased and manufactured in the United States were evaluated and assessed for cannabinoid content. Quantification and validation of cannabinoids and matrix components was accomplished using gas and liquid chromatography with mass spectrometry analysis (GC-MS and LC-MS/MS) following liquid-liquid extraction with methanol. Samples degraded by temperature (analyzed by GC-MS) showed a greater disparity from the labeled CBD content compared with samples analyzed as purchased (by LC-MS/MS). Thermal degradation of the vape liquids showed increased levels of tetrahydrocannabinol (THC). Also, extended time and temperature degradation were evaluated in vape liquids by storing them for 15 months and then varying temperature conditions before analysis, which indicated CBD transformed into other cannabinoids leading to different cannabinoid content within the vape samples. Evaluation conducted on these vape liquids indicated the route of exposure, storage conditions, and length of storage could expose consumers to unintended cannabinoids and showed a concerning level of disagreement between the products' labeled cannabinoid content and the results generated by these analyses.

Axial Phenoxylation of Aluminum Phthalocyanines for Improved Cannabinoid Sensitivity in OTFT Sensors

Cannabis producers, consumers, and regulators need fast, accurate, point-of-use sensors to detect Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) from both liquid and vapor source samples, and phthalocyanine-based organic thin-film transistors (OTFTs) provide a cost-effective solution. Chloro aluminum phthalocyanine (Cl-AlPc) has emerged as a promising material due to its unique coordinating interactions with cannabinoids, allowing for superior sensitivity. This work explores the molecular engineering of AlPc to tune and enhance these interactions, where a series of novel phenxoylated R-AlPcs are synthesized and integrated into OTFTs, which are then exposed to THC and CBD solution and vapor samples. While the R-AlPc substituted molecules have a comparable baseline device performance to Cl-AlPc, their new crystal structures and weakened intermolecular interactions increase sensitivity to THC. Grazing-incidence wide-angle X-ray scattering (GIWAXS) and atomic force microscopy (AFM) are used to investigate this film restructuring, where a significant shift in the crystal structure, grain size, and film roughness is detected for the R-AlPc molecules that do not occur with Cl-AlPc. This significant crystal reorganization and film restructuring are the driving force behind the improved sensitivity to cannabinoids relative to Cl-AlPc and demonstrate that analyte-semiconductor interactions can be enhanced through chemical modification to create more responsive OTFT sensors.

Nicotine or marijuana vaping exposure during pregnancy and altered immune responses in offspring

Electronic nicotine delivery systems (ENDS) - which include electronic cigarettes or e-cigarettes, or simply e-cigs, and marijuana vaping have become increasingly popular. ENDS devices have been established as one of the tobacco quit methods and promoted to be safer compared to traditional tobacco cigarettes. Emerging evidence demonstrates that e-cigarette and marijuana vape use can be harmful, with potential associations with cancer. Herein, we summarize the level of evidence to date for altered immune response, with a focus on cancer risks in the offspring after maternal use of, or aerosol exposures from, ENDS or marijuana vape during pregnancy. From 27 published articles retrieved from PubMed, we sought to find out identified carcinogens in ENDS aerosols and marijuana vapor, which cross the placental barrier and can increase cancer risk in the offspring. Carcinogens in vaping aerosols include aldehydes, metals, tobacco-specific nitrosamines, tobacco alkaloids, polycyclic aromatic hydrocarbons, and volatile organic compounds. Additionally, there was only one passive vaping exposure case study on a human fetus, which noted that glycerol, aluminum, chromium, nickel, copper, zinc, selenium, and lead crossed from the mother to the offspring's cord blood. The carcinogens (metals) in that study were at lower concentrations compared to the mother's biological matrices. Lastly, we observed that in utero exposures to ENDS-associated chemicals can occur in vital organs such as the lungs, kidneys, brain, bladder, and heart. Any resulting DNA damage increases the risk of tumorigenesis. Future epidemiological studies are needed to examine the effects of passive aerosol exposures from existing and emerging electronic nicotine and marijuana products on developing offspring to cancer.

Cannabis vaporisation: Understanding products, devices and risks

ISSUES

Vaporisation is a common method of cannabis administration. Inconsistent terminology and jargon regarding vaporisation has led to confusion. The increasing public interest and access to cannabis, combined with possible safety concerns associated with certain cannabis vaping products, warrants improved consumer and public and health care professional knowledge.

APPROACH

To improve this knowledge, we conducted a review of the common terminology, regulatory status, products and device types related to cannabis vaporisation.

KEY FINDINGS

Cannabis vaporisation devices can be separated into nine types. While vaporisation reduces respiratory risks associated with cannabis combustion, not all vaping products and device types carry the same level of safety. Metered dose inhalers and dried product vaporisers present the lowest safety risk due to a lower risk of toxin exposure and the use of lower tetrahydrocannabinol potency products.

IMPLICATIONS

As both vaping and cannabis use increase in popularity, focusing on accurate health education will help facilitate health promotion to encourage lower risk use. The current lack of understanding on risk differences between types of cannabis vaporisation is a missed opportunity for harm reduction. Increased opportunities for public health and health care professional education on different cannabis vaporisation devices and associated risks are warranted. Improvements to health warning labelling may also be beneficial.

CONCLUSION

Not all cannabis vaporisation devices and products carry the same level of risk. A better understanding of risk differentiation is needed among consumers and health professionals. Continued research, policy development and health education can lead to safer cannabis vaporisation.

Hexahydrocannabinol and closely related semi-synthetic cannabinoids: A comprehensive review

Since the early 2000s, there has been a turmoil on the global illicit cannabinoid market. Parallel to legislative changes in some jurisdictions regarding herbal cannabis, unregulated and cheap synthetic cannabinoids with astonishing structural diversity have emerged. Recently, semi-synthetic cannabinoids manufactured from hemp extracts by simple chemical transformations have also appeared as recreational drugs. The burst of these semi-synthetic cannabinoids into the market was sparked by legislative changes in the United States, where cultivation of industrial hemp restarted. By now, hemp-derived cannabidiol (CBD), initially a blockbuster product on its own, became a "precursor" to semi-synthetic cannabinoids such as hexahydrocannabinol (HHC), which appeared on the drug market in 2021. The synthesis and cannabimimetic activity of HHC were first reported eight decades ago in quest for the psychoactive principles of marijuana and hashish. Current large-scale manufacture of HHC is based on hemp-derived CBD extract, which is converted first by cyclization into a Δ8 /Δ9 -THC mixture, followed by catalytic hydrogenation to afford a mixture of (9R)-HHC and (9S)-HHC epimers. Preclinical studies indicate that (9R)-HHC has THC-like pharmacological properties. The animal metabolism of HHC is partially clarified. The human pharmacology including metabolism of HHC is yet to be investigated, and (immuno)analytical methods for the rapid detection of HHC or its metabolites in urine are lacking. Herein, the legal background for the revitalization of hemp cultivation, and available information on the chemistry, analysis, and pharmacology of HHC and related analogs, including HHC acetate (HHC-O) is reviewed.

Sesquiterpene-evoked phytochemical toxicity in PC12 neuronal cells reveals a variable degree of oxidative stress and alpha-tocopherol and glutathione-dependent protection

Phytochemicals are often promoted generally as antioxidants and demonstrate variable levels of reactive oxygen species (ROS) sequestration in vitro, which attributes to their neuroprotective bioactivity. Sesquiterpenes from cannabis and essential oils may demonstrate bifunctional properties towards cellular oxidative stress, possessing pro-oxidant activities by generating ROS or scavenging ROS directly. Sesquiterpenes can also oxidize forming sesquiterpene oxides, however the relative contribution they make to the bioactivity or cytotoxicity of complex botanical extracts more generally is unclear, while selected cannabis-prevalent terpenes such as β-caryophyllene may also activate cannabinoid receptors as part of their biological activity. In the present study, we investigated selected sesquiterpenes β-caryophyllene and humulene and their oxidized forms (β-caryophyllene oxide and zerumbone, respectively) against established antioxidants (ascorbic acid, α-tocopherol, and glutathione) and in the presence of cannabinoid receptor 1 and cannabinoid receptor 2 antagonists, to gain a better understanding of the molecular and cellular mechanisms of neuroprotection versus neurotoxicity in semi-differentiated rat neuronal phaeochromocytoma (PC12) cells. Our results demonstrate that the sesquiterpenes β-caryophyllene, humulene and zerumbone possess concentration-dependent neurotoxic effects in PC12 cells. Both β-caryophyllene- and humulene-evoked toxicity was unaffected by CB1 or CB2 receptor antagonism, demonstrating this occurred independently of cannabinoid receptors. Both glutathione and α-tocopherol were variably able to alleviate the concentration-dependent loss of PC12 cell viability from exposure to β-caryophyllene, humulene and zerumbone. During 4-hour exposure to sesquiterpenes only modest increases in ROS levels were noted in PC12 cells, with glutathione co-incubation significantly inhibiting intracellular ROS production. However, significant increases in ROS levels in PC12 cells were demonstrated during 24-hour incubation with either antioxidants or sesquiterpenes individually, and with additive toxicity exhibited in combination. Overall, the results highlight a concentration-dependent profile of sesquiterpene neurotoxicity independent of cannabinoid receptors and dissociated from the formation of reactive oxygen species as a marker or correlate to the loss of cell viability.

Recent advances in the analysis of electronic cigarette liquids and aerosols: Sample preparation and chromatographic characterization

Electronic cigarette (e-cigarette) usage has risen dramatically worldwide in recent years. It has been publicized as a safer alternative to the conventional combustible cigarette. This, however, has not yet been supported by robust toxicological research evidence. Analysis of the chemical compositions of e-liquids and generated aerosols is an important step in evaluating the toxicity effects of e-cigarettes. Currently, a broad spectrum of analytical methods have been employed for qualitative and quantitative analysis of chemical compositions of e-cigarette liquids and aerosols. The aim of this article is to review the advances in the chromatographic characterization of chemical composition of the latter in the recent five years. In addition, sample preparation methods for e-liquids and aerosols are surveyed and discussed. A study of the relevant literature indicates that, expectedly, gas chromatography and liquid chromatography with a variety of detection systems, particularly mass spectrometry, have been the main analytical techniques used in this field. Sample preparation procedures primarily include headspace sampling, dilute-and-shoot approach, liquid-liquid extraction and sorbent-based extraction for e-liquids and for aerosols (the latter usually with laboratory-built collection devices). Some challenges of current e-cigarette analytical research, and an overview on prospective work are also presented.

Application of gas chromatography in the analysis of phytocannabinoids: An update (2020-2023)

INTRODUCTION

Cannabinoids are a group of compounds that bind to cannabinoid receptors. They possess pharmacological properties like that of the plant Cannabis sativa. Gas chromatography (GC) is one of the popular chromatographic techniques that has been routinely used in the analysis of cannabinoids in different matrices.

OBJECTIVE

The article aims to review the literature on the application of GC-based analytical methods for the analysis of phytocannabinoids published during the period from January 2020 to August 2023.

METHODOLOGY

A thorough literature search was conducted using different databases, like Web of Knowledge, PubMed, Google Scholar, and other relevant published materials including published books. The keywords used, in various combinations, with cannabinoids being present in all combinations, in the search were cannabinoids, Cannabis sativa, marijuana, analysis, GC, quantitative, qualitative, and quality control. From the search results, only the publications that incorporate the GC analysis of phytocannabinoids were reviewed, and papers on synthetic cannabinoids were excluded.

RESULTS

Since the publication of the review article on GC analysis of phytocannabinoids in early 2020, several GC-based methods for the analysis of phytocannabinoids have appeared in the literature. While simple 1D GC-mass spectrometry (MS) and GC-flame ionisation detector (FID) methods are still quite common in phytocannabinoids analysis, 2D GC-MS and GC-MS/MS are increasingly becoming popular, as these techniques offer more useful data for identification and quantification of phytocannabinoids in various matrices. The use of automation in sample preparation and the utilisation of mathematical and computational models for optimisation of different protocols have become a norm in phytocannabinoids analysis. Pre-analyses have been found to incorporate different derivatisation techniques and environmentally friendly extraction protocols.

CONCLUSIONS

GC-based analysis of phytocannabinoids, especially using GC-MS, remains one of the most preferred methods for the analysis of these compounds. New derivatisation methods, ionisation techniques, mathematical models, and computational approaches for method optimisation have been introduced.

Parallel trajectories of vaping and smoking cannabis and their associations with mental and physical well-being among young adults

BACKGROUND

Vaping and smoking are common modes of using cannabis (THC) among young adults, but little is known about how patterns of cannabis vaping and smoking unfold over time or how using one or both types of products may differently affect mental and physical well-being. This study examines parallel processes of cannabis vaping and smoking over 5 years and mental and physical outcomes in a sample of young adults.

METHODS

Annual surveys were conducted between 2016 and 2022 with a mostly California-based cohort of 2428 young adults. Parallel process growth mixture models examined trajectories of past-month frequency of cannabis vaping and smoking from ages 20 - 25. Classes were extracted based on parallel trajectories of vaped and smoked product use. Models assessed differences in self-reported mental (anxiety, depression) and physical (ailments, subjective overall) well-being outcomes in young adulthood across classes, adjusting for demographic characteristics and mental and physical well-being at pre-baseline (average age 19).

RESULTS

Four cannabis vaping/smoking classes emerged: low use of cannabis (84.7%), decreasing smoking, low-moderate vaping (7.1%), stable moderate smoking, decreasing vaping (4.6%), and rapid increasing dual use (3.4%). Classes were similar on physical well-being indicators in young adulthood. The rapid increasing dual use class showed higher anxiety and depressive symptoms compared to other classes.

CONCLUSION

Progression to higher frequency of both vaping and smoking cannabis in young adulthood may contribute to poorer mental well-being compared to other use patterns. Targeted efforts to reduce dual vaping and smoking in young people who use cannabis may be needed.

Vaping additives cannabinoid oil and vitamin E acetate adhere to and damage the human airway epithelium

E-cigarette, or vaping product use-associated lung injury (EVALI), is a severe respiratory disorder that caused a sudden outbreak of hospitalized young people in 2019. Using cannabis oil containing vaping products, including vitamin E acetate contaminants, was found to be strongly associated with EVALI. However, the underlying tissue impacts of the condition are still largely unknown. Here, we focused on the vehicle cannabinoid oil (CBD oil) and contaminant vitamin E acetate (VEA) effects on airway epithelial cells. Primary human bronchial epithelial (HBE) cultures were exposed to e-liquid aerosols that contained CBD oil and VEA in combination or the common e-liquid components PG/VG with and without nicotine. Cell viability analysis indicated dramatically increased cell death counts after 3 days of CBD exposure, and this effect was even higher after CBD + VEA exposure. Microscopic examination of the cultures revealed cannabinoid and VEA depositions on the epithelial surfaces and cannabinoid accumulation in exposed cells, followed by cell death. These observations were supported by proteomic analysis of the cell secretions that exhibited increases in known markers of airway epithelial toxicity, such as xenobiotic enzymes, factors related to oxidative stress response, and cell death indicators. Overall, our study provides insights into the association between cannabinoid oil and vitamin E acetate vaping and lung injury. Collectively, our results suggest that the adherent accumulation of CBD oil on airway surfaces and the cellular uptake of both CBD oil- and VEA-containing condensates cause elevated metabolic stress, leading to increased cell death rates in human airway epithelial cultures.

Investigating the Effect of Medium Chain Triglycerides on the Elasticity of Pulmonary Surfactant

In recent years, vaping has increased in both popularity and ease of access. This has led to an outbreak of a relatively new condition known as e-cigarette/vaping-associated lung injury (EVALI). This injury can be caused by physical interactions between the pulmonary surfactant (PS) in the lungs and toxins typically found in vaping solutions, such as medium chain triglycerides (MCT). MCT has been largely used as a carrier agent within many cannabis products commercially available on the market. Pulmonary surfactant ensures proper respiration by maintaining low surface tensions and interface stability throughout each respiratory cycle. Therefore, any impediments to this system that negatively affect the efficacy of this function will have a strong hindrance on the individual's quality of life. Herein, neutron spin echo (NSE) and Langmuir trough rheology were used to probe the effects of MCT on the mechanical properties of pulmonary surfactant. Alongside a porcine surfactant extract, two lipid-only mimics of progressing complexity were used to study MCT effects in a range of systems that are representative of endogenous surfactant. MCT was shown to have a greater biophysical effect on bilayer systems compared to monolayers, which may align with biological data to propose a mechanism of surfactant inhibition by MCT oil.

Delta-8 tetrahydrocannabinol: a scoping review and commentary

BACKGROUND AND AIMS

Delta-8 tetrahydrocannabinol (THC) is a psychoactive substance from the Cannabis plant that has been rising in popularity in the United States since the 2018 US Farm Bill implicitly legalized it. This study reviewed research from peer-reviewed and non-peer-reviewed (e.g. anecdotal and news) reports related to delta-8 THC to summarize current knowledge and implications for public health and safety.

METHODS

A scoping review was conducted using PubMed, Scopus, Google Scholar and Google as search engines, leading to the identification of 103 documents that were summarized. The themes that emerged were (1) legality, (2) use (popularity, motives, psychoactivity/potency, benefits/consequences), (3) synthesis (byproducts, laboratory testing) and (4) retail (availability, price, packaging, youth-oriented marketing). A second author independently coded 20% of the documents, which verified the categorization of articles by these emergent themes.

RESULTS

Most research used animal/cell models or focused upon ways to identify the chemical structure of delta-8 THC in various products. Findings suggest that people often use delta-8 THC as a substitute for other substances. Anecdotally, delta-8 THC is a less potent psychoactive than delta-9 THC; however, several negative consequences have been reported. There is no federal age restriction for purchase/possession of delta-8 THC products. Delta-8 THC is readily accessible on-line, is typically less expensive than delta-9 THC and is often marketed in ways that would seemingly appeal to children. There are no regulations on synthesis, resulting in products being contaminated and/or yielding inconsistent effects. There have been thousands of calls to US poison control centers due to accidental delta-8 THC exposure among minors.

CONCLUSIONS

Most research on delta-8 THC is largely anecdotal, not peer-reviewed and does not involve human subjects. Future research should examine delta-8 THC use using nationally representative samples to more clearly understand the prevalence and consequences of use. Laws are needed to mitigate the risks of using delta-8 THC, particularly quality control of synthesis and minimum purchase age.

The E-cigarette or Vaping Product Use-Associated Lung Injury Epidemic: Pathogenesis, Management, and Future Directions: An Official American Thoracic Society Workshop Report

E-cigarette or vaping product use-associated lung injury (EVALI) is a severe pulmonary illness associated with the use of e-cigarettes or vaping products that was officially identified and named in 2019. This American Thoracic Society workshop was convened in 2021 to identify and prioritize research and regulatory needs to adequately respond to the EVALI outbreak and to prevent similar instances of disease associated with e-cigarette or vaping product use. An interdisciplinary group of 26 experts in adult and pediatric clinical care, public health, regulatory oversight, and toxicology were convened for the workshop. Four major topics were examined: 1) the public health and regulatory response to EVALI; 2) EVALI clinical care; 3) mechanisms contributing to EVALI; and 4) needed actions to address the health effects of EVALI. Oral presentations and group discussion were the primary modes used to identify top priorities for addressing EVALI. Initiatives including a national EVALI case registry and biorepository, integrated electronic medical record coding system, U.S. Food and Drug Administration regulation and enforcement of nicotine e-cigarette standards, regulatory authority over nontobacco-derived e-cigarettes, training in evaluating exogenous exposures, prospective clinical studies, standardized clinical follow-up assessments, ability to more readily study effects of cannabinoid e-cigarettes, and research to identify biomarkers of exposure and disease were identified as critical needs. These initiatives will require substantial federal investment as well as changes to regulatory policy. Overall, the workshop identified the need to address the root causes of EVALI to prevent future outbreaks. An integrated approach from multiple perspectives is required, including public health; clinical, basic, and translational research; regulators; and users of e-cigarettes. Improving the public health response to reduce the risk of another substantial disease-inducing event depends on coordinated actions to better understand the inhalational toxicity of these products, informing the public of the risks, and developing and enforcing regulatory standards for all e-cigarettes.

Perceptions About Cannabis Following Legalization Among Pregnant Individuals With Prenatal Cannabis Use in California

IMPORTANCE

As rates of prenatal cannabis use increase and cannabis legalization spreads across the US, studies are needed to understand the potential impacts of legalization from the perspectives of pregnant individuals who use cannabis.

OBJECTIVE

To characterize pregnant individuals' perspectives on legalization of cannabis for adult use in California (effective in 2018) in relation to prenatal cannabis use behaviors and beliefs.

DESIGN, SETTING, AND PARTICIPANTS

This qualitative study was conducted in Kaiser Permanente Northern California, a large health care system with universal screening for self-reported cannabis use at entrance to prenatal care. Eighteen semistructured focus groups were conducted from November 17 to December 17, 2021, using a secure video conferencing platform with Black and White pregnant participants who self-reported cannabis use during early pregnancy. Data were analyzed from March to June 2022.

MAIN OUTCOMES AND MEASURES

Video-recorded interviews were transcribed and analyzed using thematic analysis to identify major themes and subthemes.

RESULTS

Among 53 participants (mean [SD] age, 30.3 [5.2] years), 23 (43%) identified as non-Hispanic Black and 30 (57%) identified as non-Hispanic White; 16 participants (30%) reported continued cannabis use at the time of recruitment. Major themes regarding the perceived impact of legalization included easier access (via retailers and delivery), greater acceptance (including reduced stigma and more discussions about prenatal cannabis use with health care practitioners), and trust in cannabis retailers (including safety and effectiveness of diverse products sold and perceptions of cannabis retailer employees as knowledgeable, nonjudgmental, and caring). Responses were mixed about whether retailer marketing and advertising were associated with prenatal cannabis use and whether legalization resulted in reduced concerns about Child Protective Services involvement.

CONCLUSION AND RELEVANCE

The findings of this qualitative study suggest pregnant individuals perceive cannabis legalization as having reduced barriers to prenatal cannabis use and that legalization has created challenges and opportunities for supporting the health of pregnant individuals. The results of this qualitative study highlight key areas that can be further explored in future educational materials, public health campaigns, and policy adaptations to address increasing rates of prenatal cannabis use.

Cannabis - a Rewritten History and Its Pulmonary Consequences

Cannabis presents itself as another challenge of the last decade. Better and better deciphered through in-depth studies, this drug remains a source of scientific debates. Legalized in some states, it competes with tobacco regarding the effects generating respiratory symptoms, chronic bronchitis, bronchial cancer, respiratory infections, etc. In this article we will review the pharmacology, epidemiology, clinical and prevention aspects and try to demonstrate which of these are the most effective means of prevention. This review proves once again that this drug has many hidden dangers.

Chemical Interactions and Cytotoxicity of Terpene and Diluent Vaping Ingredients

Vaping devices have risen in popularity since their inception in 2007. The practice involves using a variety of commercially available devices. Internal heating systems in devices aerosolize e-liquid formulations of complex mixtures including an active ingredient (e.g., THC, CBD, and nicotine), diluents (or cutting agents), solvents, and flavoring agents (e.g., terpenes and aldehydes). The vaping toxicology literature consists of cytotoxicity studies of individual chemicals and commercial formulas. Because of the variation of e-liquid composition, there is a limited understanding of the toxicity of ingredient combinations. This study analyzed the cytotoxic effects after exposure to individual and binary mixtures of a representative terpene (+-R-limonene) and diluent (triethyl citrate) on human lung cell models. Data were analyzed to determine the effects of 97:3 and 80:20% v/v (triethyl citrate/limonene) binary mixtures. BEAS-2B cells, a bronchial epithelial cell, and A549 cells, a type II alveolar epithelial cell, served as models for comparison. LC₅₀ values were calculated and isobolograms were used to assess chemical interactions. Results show that limonene was more cytotoxic than triethyl citrate. Isobolographic analyses confirmed that the 97:3% v/v mixture resulted in an antagonistic chemical interaction. The 80:20% v/v mixture resulted in a similar result. Further testing of different ratios of binary mixtures is needed for chemical interaction screening to inform safety assessments.

A Comparison of Vaping Behavior, Perceptions, and Dependence among Individuals Who Vape Nicotine, Cannabis, or Both

Background: Electronic delivery systems (e.g., vapes, e-cigarettes) are now popular modes of cannabis and nicotine administration that are often used by the same individuals; however, we still know little about dual nicotine and cannabis vaping. Materials & Methods: An online convenience sample of adult nicotine and/or cannabis vape users residing in the United States completed a 60 min survey on sociodemographic characteristics, cannabis and/or nicotine vape use behaviors and dependence, reasons for vape use, and perceptions of benefits and harms. After data cleaning, we compared dual vs. nicotine-only and cannabis-only vape users with univariate statistics and step-wise hierarchical linear regression analyses. Additionally, we assessed the factor structure, internal consistency, and criterion and convergent validity of the Penn State Cannabis Vaping Dependence Index (PSCVDI). Results: The final sample included 357 dual, 40 cannabis, and 106 nicotine vape users. Compared to nicotine- and cannabis-only vapers, dual vapers started using their nicotine and cannabis vapes at a younger age (p < 0.001), used them for more years (p < 0.001), and were less likely to use their nicotine vape to replace combustible cigarettes (p = 0.047). Dual users vs. single-substance users did not have significantly higher nicotine or cannabis vape dependence scores after controlling for sociodemographic and use behaviors. The PSCVDI showed adequate validity for measuring cannabis vape dependence. Conclusions: This survey is the first to highlight important differences in vape use behaviors and reasons for use between dual vs. cannabis- and nicotine-only vape users.

In-situ TD-GCMS measurements of oxidative products of monoterpenes at typical vaping temperatures: implications for inhalation exposure to vaping products

Vaping is gaining in popularity. However, there is still much that remains unknown about the potential risk and harms of vaping. Formation of oxidative products is one of such areas that are not well understood. In this study, we used an in-situ thermal desorption GC/MS method to investigate the formation of oxidative products of several monoterpenes at or below typical vaping temperatures. Among the five tested monoterpenes, the unchanged portion of the parent compound in the vapour varied from 97 to 98% for myrcene to 11–28% for terpinolene. The majority of formed oxidative products in the vapour have a molecular weight of 134 (loss of two hydrogens), 150 (insertion of one oxygen and loss of two hydrogen atoms) or 152 (insertion of one oxygen atom). Three products, likely to be p-(1-propenyl)-toluene, β-pinone and fenchol were also observed. This is the first in-situ thermal desorption GC/MS study to investigate the possible formation of oxidative products of monoterpenes, one of the major components in vaping liquids, at temperatures that are relevant to the vaping process. Although the toxicity of inhaling these oxidative products is not clear yet, allergic and irritation reactions associated with oxidized monoterpene oils are well documented. Therefore, potential adverse effects of inhaling these oxidative products during vaping could be investigated to help support human risk assessment.

E-cigarette vaping associated acute lung injury (EVALI): state of science and future research needs

"E-Cigarette (e-cig) Vaping-Associated Acute Lung Injury" (EVALI) has been linked to vitamin-E-acetate (VEA) and Δ-9-tetrahydrocannabinol (THC), due to their presence in patients' e-cigs and biological samples. Lacking standardized methodologies for patients' data collection and comprehensive physicochemical/toxicological studies using real-world-vapor exposures, very little data are available, thus the underlying pathophysiological mechanism of EVALI is still unknown. This review aims to provide a comprehensive and critical appraisal of existing literature on clinical/epidemiological features and physicochemical-toxicological characterization of vaping emissions associated with EVALI. The literature review of 161 medical case reports revealed that the predominant demographic pattern was healthy white male, adolescent, or young adult, vaping illicit/informal THC-containing e-cigs. The main histopathologic pattern consisted of diffuse alveolar damage with bilateral ground-glass-opacities at chest radiograph/CT, and increased number of macrophages or neutrophils and foamy-macrophages in the bronchoalveolar lavage. The chemical analysis of THC/VEA e-cig vapors showed a chemical difference between THC/VEA and the single THC or VEA. The chemical characterization of vapors from counterfeit THC-based e-cigs or in-house-prepared e-liquids using either cannabidiol (CBD), VEA, or medium-chain triglycerides (MCT), identified many toxicants, such as carbonyls, volatile organic compounds, terpenes, silicon compounds, hydrocarbons, heavy metals, pesticides and various industrial/manufacturing/automotive-related chemicals. There is very scarce published toxicological data on emissions from THC/VEA e-liquids. However, CBD, MCT, and VEA emissions exert varying degrees of cytotoxicity, inflammation, and lung damage, depending on puffing topography and cell line. Major knowledge gaps were identified, including the need for more systematic-standardized epidemiological surveys, comprehensive physicochemical characterization of real-world e-cig emissions, and mechanistic studies linking emission properties to specific toxicological outcomes.

Chemical Emissions From Heated Vitamin E Acetate—Insights to Respiratory Risks From Electronic Cigarette Liquid Oil Diluents Used in the Aerosolization of Δ9-THC-Containing Products

As of February 18, 2020, the e-cigarette, or vaping, product use associated lung injury (EVALI) outbreak caused the hospitalization of a total of 2,807 patients and claimed 68 lives in the United States. Though investigations have reported a strong association with vitamin E acetate (VEA), evidence from reported EVALI cases is not sufficient to rule out the contribution of other chemicals of concern, including chemicals in either THC or non-THC products. This study characterized chemicals evolved when diluent oils were heated to temperatures that mimic e-cigarette, or vaping, products (EVPs) to investigate production of potentially toxic chemicals that might have caused lung injury. VEA, vitamin E, coconut, and medium chain triglyceride (MCT) oil were each diluted with ethanol and then tested for constituents and impurities using a gas chromatograph mass spectrometer (GC/MS). Undiluted oils were heated at 25°C (control), 150°C, and 250°C in an inert chamber to mimic a range of temperatures indicative of aerosolization from EVPs. Volatilized chemicals were collected using thermal desorption tubes, analyzed using a GC/MS, and identified. Presence of identified chemicals was confirmed using retention time and ion spectra matching with analytic standards. Direct analysis of oils, as received, revealed that VEA and vitamin E were the main constituents of their oils, and coconut and MCT oils were nearly identical having two main constituents: glycerol tricaprylate and 2-(decanoyloxy) propane-1,3-diyl dioctanoate. More chemicals were measured and with greater intensities when diluent oils were heated at 250°C compared to 150°C and 25°C. Vitamin E and coconut/MCT oils produced different chemical emissions. The presence of some identified chemicals is of potential health consequence because many are known respiratory irritants and acute respiratory toxins. Exposure to a mixture of hazardous chemicals may be relevant to the development or exacerbation of EVALI, especially when in concert with physical damage caused by lung deposition of aerosols produced by aerosolizing diluent oils.