Assessment of E-cigarette impact on smokers: The importance of experimental conditions relevant to human consumption

Xenobiotics Delivered by Electronic Nicotine Delivery Systems: Potential Cellular and Molecular Mechanisms on the Pathogenesis of Chronic Kidney Disease

Chronic kidney disease (CKD) is characterized as sustained damage to the renal parenchyma, leading to impaired renal functions and gradually progressing to end-stage renal disease (ESRD). Diabetes mellitus (DM) and arterial hypertension (AH) are underlying diseases of CKD. Genetic background, lifestyle, and xenobiotic exposures can favor CKD onset and trigger its underlying diseases. Cigarette smoking (CS) is a known modified risk factor for CKD. Compounds from tobacco combustion act through multi-mediated mechanisms that impair renal function. Electronic nicotine delivery systems (ENDS) consumption, such as e-cigarettes and heated tobacco devices, is growing worldwide. ENDS release mainly nicotine, humectants, and flavorings, which generate several byproducts when heated, including volatile organic compounds and ultrafine particles. The toxicity assessment of these products is emerging in human and experimental studies, but data are yet incipient to achieve truthful conclusions about their safety. To build up the knowledge about the effect of currently employed ENDS on the pathogenesis of CKD, cellular and molecular mechanisms of ENDS xenobiotic on DM, AH, and kidney functions were reviewed. Unraveling the toxic mechanisms of action and endpoints of ENDS exposures will contribute to the risk assessment and implementation of proper health and regulatory interventions.

Tracing the composition of single e-cigarette aerosol droplets in situ by laser-trapping and Raman scattering

The partitioning of components between droplets and the gas phase in e-cigarette aerosols has a significant impact on deposition within the respiratory tract. However, exclusive detection of droplet composition has, so far, been elusive. Consequently, the dynamics of partitioning between droplets and the gas phase remains unknown. Here, we combine optical trapping of single droplets with in situ Raman scattering for destruction-free monitoring of e-cigarette droplet composition with a time resolution of seconds. We find that the initial droplet composition is very close to the composition of the e-liquid. Upon dilution with air, the droplet composition changes exponentially on a time scale of seconds, mainly because of evaporation of propylene glycol. The nicotine content in the droplet is controlled by the pH. Nicotine evaporates from the droplets under basic conditions, but remains in the liquid under acidic conditions. These results are crucial for advancing e-liquid research and manufacturing.

Modeling drug exposure in rodents using e-cigarettes and other electronic nicotine delivery systems

Smoking tobacco products is the leading cause of preventable death worldwide. Coordinated efforts have successfully reduced tobacco cigarette smoking in the United States; however, electronic cigarettes (e-cigarette) and other electronic nicotine delivery systems (ENDS) recently have replaced traditional cigarettes for many users. While the clinical risks associated with long-term ENDS use remain unclear, advancements in preclinical rodent models will enhance our understanding of their overall health effects. This review examines the peripheral and central effects of ENDS-mediated exposure to nicotine and other drugs of abuse in rodents and evaluates current techniques for implementing ENDS in preclinical research.

A Deliberate Choice? Exploring the Decision to Switch from Cigarettes to E-Cigarettes

E-cigarettes are increasingly popular among both cigarette smokers and non-users. Although smoking cessation yields the most individual and population health benefits, switching to exclusive e-cigarette use offers some individual health benefits for cigarette smokers. However, e-cigarette use is not harmless, and its use among non-cigarette smokers should be prevented. Our study aims to explore the decision-making process about e-cigarettes among an e-cigarette users, cigarette smokers, and non-users. We conducted 12 semi-structured focus group interviews with e-cigarette users, cigarette smokers, and non-users. We performed a thematic analysis of the interview transcripts. First, knowledge reported by e-cigarette users was mainly based on other users’ experiences. Second, cigarette smokers and non-users were more negative towards e-cigarettes than e-cigarette users. Third, e-cigarette users considered switching from cigarette smoking to e-cigarette use by deliberating relevant information, and weighing up the benefits and disadvantages of e-cigarette use versus smoking. Additionally, important factors in the decision-making process were a perception of risks and benefits of e-cigarettes compared to cigarettes, a supportive social environment about e-cigarette use, and trust in information offered about the risks and benefits of e-cigarettes. Our findings provide insight into what we can learn from the conscious decision-making process of e-cigarette users who switched from cigarettes to e-cigarettes. This information can be considered to develop targeted communications strategies to stimulate a conscious decision-making process, these may highlight benefits of switching to e-cigarettes for cigarette smokers, discussing the risks of smoking, and correcting misperceptions about the perceived risks and benefits of e-cigarette use.