E-cigarettes: a scientific review

Effect of Nicotine on Pulmonary Pathogenic Bacteria

Exposure to cigarette smoke significantly enhances susceptibility to bacterial infections by inducing physiological and structural alterations, including immune system dysregulation. This exposure also augments bacterial virulence including biofilm formation, leading to severe infectious diseases and antibiotic resistance. Notably, cigarette smoke exposure increases the incidence of pneumonia by up to 2.5-fold and tuberculosis by up to 4.1-fold. Nicotine, a primary constituent of cigarette smoke, has been extensively characterized for its immunomodulatory effects. However, despite the wealth of knowledge on nicotine's impact on the host immune response, there is a paucity of data regarding its direct effects on various pulmonary pathogens. In the present review, we discuss the main findings in this field.

Examining the e-cigarette scenario based on distribution, availability, marketing, and banning: A GIS-Based qualitative study in Bangladesh

BACKGROUND

Globally, over 81 million people use e-cigarettes, and the majority of them are young adults. Using e-cigarettes causes different types of adverse health effects both in adults and elderly people. Over time, using e-cigarettes has detrimental consequences on lung function, brain development and numerous other illnesses.

METHODS

This study employed a mixed-methods conducted between June and September 2023, comprising two phases: Geographical Information System (GIS) mapping of available e-cigarette point-of-sale (POS) locations and conducting 15 in-depth interviews (IDIs) with e-cigarette retailers, along with 5 key informant interviews (KIIs) involving tobacco control activists and policy experts. ArcGIS was employed for spatial analysis, creating distribution and type maps, and buffer and multi-buffer ring analyses were conducted to assess proximity to hospitals and academic institutions. Data analysis involved descriptive statistics for GIS mapping and qualitative analysis for interview transcripts, utilizing a priori codebook and thematic analysis.

RESULTS

A total of 276 POS were mapped in the entire Dhaka city. About 55 POS were found within 100m distance from academic institutions in Dhaka city, which offers the easy accessibility of young generations to e-cigarettes. The younger generation is becoming the major target for e-cigarettes because of their alluring flavors, appealing looks, and variation in flavors. Sellers have been using different marketing tactics such as postering, offering discounts and using internet marketing on social media. Moreover, they try to convince the customers by saying that e-cigarettes are 'not harmful' or 'less harmful'. However, retailers were mostly taking e-cigarettes from local wholesalers or distributors. Customers buy these products both from in-store and online services. Due to the absence of laws and regulations on e-cigarettes in Bangladesh, the availability, marketing, and selling of e-cigarettes are increasing alarmingly.

CONCLUSION

E-cigarette retail shops are mostly surrounded by academic institutions, and it is expanding. Besides, frequent exposure, easy accessibility, and tactful promotion encourage the younger generations to consume e-cigarettes. The government should take necessary control measures on manufacturing, storage, advertising, promotion, sponsorship, marketing, distribution, sale, import, and export in order to safeguard the health and safety of young and future generations.

E-cigarettes and vaping, new spotlight on smoking as an old cardiovascular risk factor?

Smoking is one of the leading causes of chronic non-communicable diseases and a significant risk factor for cardiovascular and respiratory diseases. While global tobacco consumption has decreased over the past two decades, the use of e‑cigarettes and water pipes (shisha) has surged at an alarming rate, particularly among younger individuals. E‑cigarettes do not offer a completely risk-free alternative to traditional cigarettes, as the vast array of flavors and ease of use contribute to a growing number of dependent users. Furthermore, they are not necessarily effective in overcoming nicotine addiction. This contribution provides an overview of the cardiovascular health impacts associated with shisha smoking and e‑cigarette vaping, with a particular emphasis on the detrimental effects on endothelial function. The harmful biological effects of the toxic substances in these products, especially oxidative stress and inflammatory responses, are also discussed. Finally, the current state of recommendations, legal regulations, and commercial advertising are summarized.

Quantification of Size-Binned Particulate Matter in Electronic Cigarette Aerosols Using Multi-Spectral Optical Sensing and Machine Learning

To monitor health risks associated with vaping, we introduce a multi-spectral optical sensor powered by machine learning for real-time characterization of electronic cigarette aerosols. The sensor can accurately measure the mass of particulate matter (PM) in specific particle size channels, providing essential information for estimating lung deposition of vaping aerosols. For the sensor's input, wavelength-specific optical attenuation signals are acquired for three separate wavelengths in the ultraviolet, red, and near-infrared range, and the inhalation pressure is collected from a pressure sensor. The sensor's outputs are PM mass in three size bins, specified as 100-300 nm, 300-600 nm, and 600-1000 nm. Reference measurements of electronic cigarette aerosols, obtained using a custom vaping machine and a scanning mobility particle sizer, provided the ground truth for size-binned PM mass. A lightweight two-layer feedforward neural network was trained using datasets acquired from a wide range of puffing conditions. The performance of the neural network was tested using unseen data collected using new combinations of puffing conditions. The model-predicted values matched closely with the ground truth, and the accuracy reached 81-87% for PM mass in three size bins. Given the sensor's straightforward optical configuration and the direct collection of signals from undiluted vaping aerosols, the achieved accuracy is notably significant and sufficiently reliable for point-of-interest sensing of vaping aerosols. To the best of our knowledge, this work represents the first instance where machine learning has been applied to directly characterize high-concentration undiluted electronic cigarette aerosols. Our sensor holds great promise in tracking electronic cigarette users' puff topography with quantification of size-binned PM mass, to support long-term personalized health and wellness.

Prognosis after switching to electronic cigarettes following percutaneous coronary intervention: a Korean nationwide study

BACKGROUND AND AIMS

Despite the increasing popularity of electronic cigarettes (E-cigarettes), the prognostic impact of switching to E-cigarettes in smokers with coronary artery disease who have undergone percutaneous coronary intervention (PCI) remains unclear.

METHODS

Using a nationwide cohort from the Korean National Health Insurance database, 17 973 adults (≥20 years) identified as smokers (based on a health screening examination within 3 years before PCI) who underwent health screening within 3 years after PCI were enrolled to determine changes in smoking habits. Patients were classified as continued combustible cigarette users, successful quitters, or switchers to E-cigarettes. The group switching to E-cigarettes was further divided into dual users (using both combustible and E-cigarettes) and those exclusively using E-cigarettes. Primary outcomes included major adverse cardiac events (MACEs), a composite of all-cause death, spontaneous myocardial infarction, and repeat revascularization.

RESULTS

Among the total population, 8951 patients (49.8%) continued using combustible cigarettes, 1694 (9.4%) were switched to E-cigarettes, and 7328 (40.7%) successfully quit smoking after PCI. During a median follow-up of 2.4 years, the cumulative incidence of MACE was lower among E-cigarette switchers (10%) or quitters (13.4%) than among continued combustible cigarette users (17%). When continued combustible cigarette users were used as the reference, the multivariable-adjusted hazard ratios with 95% confidence intervals for MACE were 0.82 (0.69-0.98) for switchers to E-cigarettes and 0.87 (0.79-0.96) for successful quitters. Compared with dual users, entirely switching to E-cigarettes was associated with a significantly lower MACE risk (hazard ratio 0.71; 95% confidence interval 0.51-0.99).

CONCLUSIONS

Among smokers who underwent PCI for coronary artery disease, switching to E-cigarette use (particularly complete transition) or quitting smoking was associated with reduced MACE risk than with continued combustible cigarette use.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT06338761.

Interactions between ENDS and cigarette use: evidence from a 2022 national telephone survey in South Africa

INTRODUCTION

Electronic nicotine delivery systems (ENDS) may serve as a cessation tool for people who smoke cigarettes. However, for people who do not smoke, ENDS may be a gateway to nicotine addiction and cigarette use. This paper aims to quantify these behaviours in South Africa.

METHODS

We analysed a nationally representative telephone survey of 21 263 South Africans living in urban areas. For those respondents who had used both products (N=771), we developed a typology that describes the sequence in which cigarette and ENDS initiation occurred. 'On-rampers' describe people who used ENDS first and later initiated cigarette smoking. 'Off-rampers' describe people who used cigarettes first, took up ENDS and later quit cigarettes while still using ENDS. 'Failed off-rampers' describe people who started using ENDS while smoking cigarettes but later quit using ENDS. 'Continuing dual consumers' describe people still using both products at the time of the interview.

RESULTS

Of the overall sample (N=21 263), 1.7% used or had used ENDS but had no history of using cigarettes. Of dual consumers (N=771), 8.8% were classified as 'on-rampers', 13.9% as 'off-rampers', 20.9% as 'failed off-rampers' and 56.4% as 'continuing dual consumers'. Roughly half of those classified as off-rampers, failed off-rampers or continuing dual consumers stated that they started using ENDS to help them quit cigarettes.

CONCLUSIONS

The typology reveals a multifaceted relationship between ENDS and cigarette use in South Africa. Policy interventions should aim to minimise on-ramping and maximise off-ramping. Given the high prevalence of continued dual use and failed off-ramping, targeted cessation support should be provided for people who use ENDS and are trying to quit cigarettes.

Impact of electronic cigarettes (e-cigs) and heat-not-burn/heated tobacco products (HnB/HTP) on asthma and chronic obstructive pulmonary disease: a viewpoint of the Italian Society of Internal Medicine

The association of cigarette smoking with several severe and very severe diseases (oncological, cardiovascular, respiratory) which have dramatic epidemiological, medical, and financial impact, is a well-known public threat. Asthma and chronic obstructive pulmonary disease (COPD) are highly prevalent diseases in Italy, posing significant public health challenges. Tobacco smoking, a primary risk factor for COPD and a common asthma trigger, remains a critical preventable public health issue. While universally acknowledged that quitting smoking drastically reduces the risk of smoking-related health issues, a significant portion of smokers and patients find quitting challenging or undesirable, hence a need for new ways to deal with it. A worth considering alternative might be the switch to electronic cigarettes (e-cig), and heat-not-burn/heated tobacco products (HnB/HTP). Emerging evidence suggests potential benefits in asthma and COPD management when transitioning from traditional smoking to e-cigs or HnB devices. However, the effectiveness of these products in facilitating smoking cessation is still debated, alongside concerns about their role in promoting smoking initiation among non-smokers. Internists are among the physicians who most frequently assist patients with smoking-related diseases, and in this perspective they cannot avoid paying attention to the progressive diffusion of smoking products alternative to the traditional cigarette, and to the controversies with respect to their use. In this context, the Italian Society of Internal Medicine, also recognizing a growing need for clarity for healthcare providers, has undertaken a comprehensive analysis of existing literature to offer an informed perspective on the health impact of e-cigs and HnB/HTP on asthma and COPD.

Alveolar macrophage function is impaired following inhalation of berry e-cigarette vapor

In the lower respiratory tract, the alveolar spaces are divided from the bloodstream and the external environment by only a few microns of interstitial tissue. Alveolar macrophages (AMs) defend this delicate mucosal surface from invading infections by regularly patrolling the site. AMs have three behavior modalities to achieve this goal: extending cell protrusions to probe and sample surrounding areas, squeezing the whole cell body between alveoli, and patrolling by moving the cell body around each alveolus. In this study, we found Rho GTPase, cell division control protein 42 (CDC42) expression significantly decreased after berry-flavored e-cigarette (e-cig) exposure. This shifted AM behavior from squeezing to probing. Changes in AM behavior led to a reduction in the clearance of inhaled bacteria, Pseudomonas aeruginosa. These findings shed light on pathways involved in AM migration and highlight the harmful impact of e-cig vaping on AM function.

The Impact of Heat-Not-Burn, E-Cigarettes, and Cigarettes on Small Airway Function

Introduction

E-cigarettes and heated tobacco products (HTPs) are gaining worldwide significance. The tobacco industry is promoting these products as healthier alternatives to conventional cigarettes.

Methods

In this four-arm crossover study, we examined the acute effects of cigarette smoking, vaping IQOS, or vaping e-cigarettes (with or without nicotine) on hemodynamics, arterial stiffness, and small airways. Twenty subjects (10 male, 10 female), all occasional smokers, completed each study arm. There was at least a 48 h washout period before each test day. Arterial stiffness and peripheral and central hemodynamics were assessed using Mobil-O-Graph™ (I.E.M., Germany), whereas tremoFlo® c-100 (Thoracic Medical Systems Inc) was used to evaluate the effects on the small airways and resistance.

Results

Cigarettes, IQOS, e-cigarettes containing nicotine, and nicotine-free e-cigarettes had similar effects on peripheral and central hemodynamics as well as on arterial stiffness. We observed a significant increase in all parameters. However, only nicotine-containing products lead to increased bronchial obstruction, higher reactance, and a higher tidal volume.

Conclusion

Therefore, we concluded that cigarettes, IQOS, and e-cigarettes have similar effects on hemodynamics. No differences were observed between the nicotine-containing and nicotine-free e-cigarettes. All nicotine-containing products also influence small airways. These findings suggest that e-cigarettes and HTPs are not healthier alternatives than conventional cigarettes.

To use or not to use electronic cigarettes? Reasons for use, stopping use and their behavioural sequelae among Mexicans who smoke

INTRODUCTION

Reasons for using and stopping the use of e-cigarettes and their associations with transitions in nicotine product use are relatively unknown in countries with e-cigarette bans, such as Mexico.

METHODS

Data comes from an open cohort of people who smoke in Mexico, surveyed every 4 months from November 2018 to November 2021. Those who smoked and used e-cigarettes at time t (n=904 individuals, 1653 observations) were categorised at 4-month follow-up (t+1): (1) continued 'dual use', (2) exclusive smoking, (3) exclusive use of e-cigarettes or neither product. For people who formerly used e-cigarettes at time t (n=332 individuals, 372 observations), follow-up categories were: (1) continued exclusive smoking; (2) re-initiated e-cigarette use. Multinomial and logistic models regressed follow-up status (ref=status at time t) on reasons for using or stopping e-cigarette use, respectively, at time t, adjusting for covariates.

RESULTS

The most prevalent reasons for current e-cigarette use were 'they were less harmful to others' (40.5%) and 'enjoyable' (39.0%). Those who reported using e-cigarettes because they were less harmful to others (Adjusted Relative Risk Ratio (ARRR)=0.67), more enjoyable (ARRR=0.52), could help them to quit smoking (ARRR=0.65), or to control weight (ARRR=0.46) were less likely to return to exclusively smoking. Among people who formerly used e-cigarettes, lack of satisfaction was the primary reason for stopping e-cigarette use (32%) and those who reported this were less likely to start using e-cigarettes again at follow-up (Adjusted Odds Ratio (AOR)=0.58).

CONCLUSIONS

Specific reasons for using and stopping e-cigarettes predict changes in smoking and e-cigarette use, and targeting these beliefs could promote desired behaviour changes.

An overview of traditional smoking cessation interventions and E-cigarettes

Many people still struggle with quitting smoking despite available treatment options, making it one of the most significant public health challenges that our society faces. The use of electronic cigarettes (E-cigarettes) has become increasingly popular among people who are seeking to quit smoking. The objective of this review paper is to present a comprehensive analysis of the mechanisms, several types, and impact of E-cigarettes, along with supporting evidence indicating their efficacy in aiding smokers to quit tobacco usage. Additionally, the review discusses recent developments in the treatment of smoking cessation, which include conventional smoking cessation methods. Also, the review discusses the challenges, potential risks, ethical considerations, and controversies surrounding the use of E-cigarettes. The present review presents a comprehensive examination of the existing methods and approaches employed in smoking cessation, including the emerging utilization of E-cigarettes as an effective option in smoking cessation. It explores their efficacy as a valuable instrument in promoting smoking cessation.

Disparities in Transitions From E-cigarette Use to Other Tobacco Use Patterns Among Sexual Minority Versus Heterosexual Women and Men in the United States

INTRODUCTION

Despite elevated rates of e-cigarette use among sexual minority versus heterosexual young adults, limited research has examined sexual identity in relation to transitions from e-cigarette use to other tobacco use patterns.

METHODS

We analyzed data from 608 US young adults in a 2-year study (2018-2020) who reported using e-cigarettes in the past 6 months (time period between assessments) but no other tobacco product at baseline (Fall 2018). Multinomial logistic regressions among women and men, separately, examined associations between sexual identity and past 6-month tobacco use in Fall 2020 (nonuse [referent group] vs e-cigarette only, other tobacco product only, e-cigarette and other tobacco product dual use), controlling for age and race/ethnicity.

RESULTS

Among women (n = 340; mean [M]age = 23.42; n = 147 [43.4%] sexual minority; 29.4% racial/ethnic minority), 34.4% reported nonuse at follow-up, 26.8% e-cigarette only, 10.3% other tobacco product only, and 28.5% e-cigarette and other tobacco product dual use. Sexual minority (vs heterosexual) women displayed greater odds of e-cigarette-only use, as well as dual use relative to nonuse at follow-up. Among men (n = 244; Mage = 24.30; n = 51 [20.9%] sexual minority; 36.1% racial/ethnic minority), 25.4% reported no use, 20.9% e-cigarette only, 17.2% other tobacco product only, and 36.5% dual use at follow-up. Sexual minority (vs heterosexual) men displayed lower odds of e-cigarette only, other tobacco product only, and dual use relative to nonuse at follow-up.

CONCLUSIONS

Research is needed to assess and intervene on tobacco/nicotine product perceptions (eg, harm, social acceptability) and reasons for use (eg, mood regulation) associated with high-risk tobacco use patterns and trajectories, particularly among sexual minority young adult women who may have distinct profiles and risks associated with use.

Perception and the influence of information toward e-cigarette smoking behavior

INTRODUCTION

Perceptions, personal perspectives, and public awareness of e-cigarette information have a significant impact on e-cigarette smoking behavior, and provide comprehensive information that can help reduce interest in e-cigarette smoking and reduce the number of new smokers. This study aimed to investigate the perceptions towards e-cigarettes related to e-cigarette use and how that information related to people's use of them.

METHODS

The data for this cross-sectional study were collected via an online questionnaire. Thai nationals who were aged ≥18 years provided data between June 2021 and January 2022. Multivariable logistic regression and the chi-squared test were used to analyze the data.

RESULTS

There were 340 respondents, 76 e-cigarette users, and 264 non-e-cigarette users. Most of the perceptions of information that differed statistically significantly between e-cigarette users and non-e-cigarette users included information on regulations, products, health effects, and the effectiveness of smoking cessation. The association between factors and e-cigarette smoking behavior revealed that the perception of the product information and male gender were associated with e-cigarette smoking behavior (AOR=13.59; 95% CI: 2.35-78.60, and AOR=5.19; 95% CI: 2.87-9.40, respectively).

CONCLUSIONS

The perception of e-cigarette product information and male gender were associated with e-cigarette smoking behavior.

The global prevalence of E-cigarettes in youth: A comprehensive systematic review and meta-analysis

Objectives

Smoking, especially cigarettes, is known as one of the most common social and health problems among people. E-cigarettes are another form of tobacco that has been an ordinary daily occurrence.Study Design: systematic review and meta-analysis.

Methods

Systematic searching of databases was performed in Scopus, Web of Science, PubMed, Science Direct, MagIran, IranDoc, SID and Google search engine based on the PRISMA 2020 guideline. This search was conducted by the end of May 2021. Following full-text assessments, the related data were extracted from the papers. Newcastle-Ottawa scale was also used to evaluate the quality of methodology of the articles. Finally, study analysis was performed using Comprehensive Meta-Analysis software (version 2) based on the random effect model.

Results

Global prevalence of E-cigarette in younger individuals was 16.8 (95 % CI: 10.6-25.6) and 4.8 (95 % CI: 3-7.6) in the Ever and Current modes of E-cigarette, respectively. We also found that E-cigarettes were used more common in young boys than young girls in both Ever and Current modes. In young boys, the prevalence of E-cigarette were 18.8 (95 % CI: 8.4-36.8) and 4.9 (95 % CI: 3-8) in both modes of Ever and Current, respectively. In young girls, these factors were 9.9 (95 % CI: 5-18.6) and 1.6 (95 % CI: 1-3.1) in both modes of Ever and Current, respectively.

Conclusions

The global prevalence of e-cigarettes among young people, especially young boys, is increasing. Based on this, the prevention and management of the damage of this social phenomenon requires comprehensive global study, planning and policy.

Rates of adverse events and related risk factors following e-cigarette use

BACKGROUND

E-cigarettes have emerged as popular products, especially for younger populations. However, concerns regarding health effects exist and there is a notable gap in understanding the prevalence and nature of adverse events. This study aims to examine the rate of adverse events in individuals who use e-cigarettes in a large sample.

METHODS

A cross-sectional survey was conducted with a sample of 4695 current and former e-cigarette users with a median age of 34 years. The survey collected data on e-cigarette use, adverse events experienced, product characteristics, related behaviors, sociodemographic factors and presence of medical comorbidities. Statistical analyses were conducted using Pearson's chi-squared tests and logistic regression.

RESULTS

A total of 78.9% of respondents reported experiencing an adverse event within 6 h of using a vaping device, with the most common events being headache, anxiety and coughing. Product characteristics and related behaviors significantly influenced the risk of adverse events. There were also sociodemographic disparities, with Hispanic respondents and those with at least college-level education reporting higher rates of adverse events.

CONCLUSIONS

Our study found a high rate of adverse events among e-cigarette users. We identified that certain e-cigarette product characteristics, behaviors and medical comorbidities significantly increased the risk of these events.

Association of Electronic Cigarette Usage with the Subsequent Initiation of Combustible Cigarette Smoking among Dental Students in Riyadh, Saudi Arabia: A Longitudinal Study

The use of electronic cigarettes, or "e-cigarettes", among youths has sparked worries about the possibility of nicotine dependence as a serious public health issue. Dental practitioners play a critical role in helping their patients quit smoking. Dental schools across the globe have policies encouraging their students to help patients quit smoking. Current research, however, indicates that a significant portion of dental students smoke combustible cigarettes and use e-cigarettes. According to studies, using e-cigarettes has resulted in the subsequent initiation of combustible cigarette smoking among its users. The aim of this study was to determine the association between the use of electronic cigarettes and the subsequent initiation of combustible cigarette smoking among dental students who were not attitudinally susceptible to smoking combustible cigarettes. A longitudinal cohort study was conducted among 121 study participants who were never combustible cigarette users and were attitudinally non-susceptible to smoking at baseline. At baseline, 66 (54.6%) study participants were categorized as e-cigarette users who were attitudinally non-susceptible to combustible cigarette smoking, and 55 (45.4%) study participants were categorized as non-users who were attitudinally non-susceptible to combustible cigarette smoking. The initiation of combustible cigarette smoking was assessed at 6- and 12-month intervals. Binomial regression analysis of the outcome at the end of one-year follow-up, when analyzed with independent variables, revealed a significant influence of e-cigarette use on taking up combustible cigarette smoking [Relative Risk: 9.395; 95% CI: 3.03-29.04]. Chi-squared analysis of independent variables revealed e-cigarette use to be significantly associated with fathers' education level (p = 0.00), parental cigarette smoking status (p = 0.00), cigarette smoking among friends (p = 0.00), and family income (p = 0.00). E-cigarette users are more likely to believe it to be healthier (p = 0.00) than combustible smoking. In the present study, e-cigarette usage demonstrated a significant influence on taking up combustible cigarette smoking among its users. Educational institutions should implement stringent policies and regulations to prevent health professionals from using these products.

Evaluating smokers' opinions on smoking and customized cessation in a Thailand University context: A qualitative study

INTRODUCTION

In Thailand, smoking cessation services have been developed to reach smokers who want to quit. However, in universities, smoking cessation services are still limited. This study aimed to identify smokers' opinions on smoking and customized cessation, and to synthesize a cessation model in the university context using the Health Belief Model.

METHODS

A qualitative research method was designed. In-depth interviews with semi-structured questions following the Health Belief Model framework were conducted with students, teachers, and supporting staff who were current smokers. The study was conducted from January to March 2022 at a Thai public university comprising schools of health sciences. Purposive sampling and a snowball technique were applied until data saturation was reached. Interview questions were constructed and validated for content. Verbatim transcriptions were used to perform thematic analysis with investigator triangulation.

RESULTS

Forty-three participants were included in this study. Of six main themes and 19 subthemes, most subthemes were consistent between groups except in economic-related themes and customized cessation services. Perceptions of harm showed positive awareness of self-harm and harm to others. Barriers included addiction, being around smokers, social norms, not trusting the counseling services, and having no information about the services. Self-efficacy to quit smoking was found in a few participants. Customized cessation services varied among groups and included convenient services with 24/7 services, services units, generous counselors, communication with an application, online counseling, and medications for cessation. Moreover, the cessation services in a university were mentioned including a quit-smoking community, more activity areas, fewer smoking areas, alliance counselors from schools, and more public relations for cessation units.

CONCLUSIONS

The perception and self-awareness of harm ranged from relaxed to being serious. Because of barriers, smoking cessation was hard to achieve, and it was hard to reach smokers. Strategies to support cessation were suggested by providing health education programs, promoting facilities and activities on campus, and designing easily accessible and customized cessation services.

E-cigarettes exacerbate allergic inflammation via cytokine induction and MUC5AC/5B expression in a murine asthma model

The effects of electronic cigarettes (e-cigarettes) vapor on inflammation and mucin secretion on asthmatics remain insufficiently explored. This study investigated the effects of e-cigarette vapor on allergic inflammation, cytokine production, and MUC5AC/5B expression in murine asthma model. Airway hyperresponsiveness was significantly higher in the e-cigarette-exposed ovalbumin (OVA) sensitization group than in the control, e-cigarette exposure, and OVA sensitization groups. The e-cigarette-exposed OVA sensitization group showed significantly greater infiltration of inflammatory cells and Th2-mediated inflammatory cytokines (interleukin-4 and -5) compared to the control, e-cigarette exposure, and OVA sensitization groups. MUC5AC mucin levels were significantly elevated in the e-cigarette exposure, OVA sensitization, and e-cigarette-exposed OVA sensitization groups, whereas MUC5B mucin levels were significantly elevated in the OVA sensitization and e-cigarette-exposed OVA sensitization groups. The results may suggest that the exposure to e-cigarette vapor in an asthmatics promoted allergic inflammation and increased mucin secretion, ultimately leading to the exacerbation of asthma.

Prevalence of Adverse Respiratory Symptoms Among E-Cigarette Users in Saudi Arabia - A Cross-Sectional Study

Electronic cigarettes, frequently referred to as e-cigarettes, have emerged as a controversial and rapidly growing phenomenon in the realm of tobacco and nicotine consumption worldwide. This study reports the prevalence of respiratory symptoms among e-cigarette users. This study also helps to understand the potential harmful effects and importance of quitting e-cigarette smoking. An observational cross-sectional study was carried out in Saudi Arabia. The study period was from September 2022 to August 2023. The sample size was 447 participants. Among recent e-cigarette users in this Saudi study, usage varied, with 44.1% using 1-5 days, 33.6% using 6-30 days, and 22.4% using e-cigarettes previously but not in the previous month. Vape devices were predominant (42.7%). There were significant associations emerged between e-cigarette use frequency and symptoms such as fatigue, breathlessness, and shortness of breath. E-cigarette use was notably linked to asthma-related symptoms, underscoring its concerning impact on respiratory health (P < 0.05). E-cigarette consumption has a significant impact on respiratory effects and specifically asthma-related symptoms among this Saudi population.

Public perceptions of synthetic cooling agents in electronic cigarettes on Twitter

Amid a potential menthol ban, electronic cigarette (e-cigarette) companies are incorporating synthetic cooling agents like WS-3 and WS-23 to replicate menthol/mint sensations. This study examines public views on synthetic cooling agents in e-cigarettes via Twitter data. From May 2021 to March 2023, we used Twitter Streaming Application Programming Interface (API), to collect tweets related to synthetic cooling agents with keywords such as 'WS-23,' 'ice,' and 'frozen.' The deep learning RoBERTa (Robustly Optimized BERT-Pretraining Approach) model that can be optimized for contextual language understanding was used to classify attitudes expressed in tweets about synthetic cooling agents and identify e-cigarette users. The BERTopic (a topic modeling technique that leverages Bidirectional Encoder Representations from Transformers) deep-learning model, specializing in extracting and clustering topics from large texts, identified major topics of positive and negative tweets. Two proportion Z-tests were used to compare the proportions of positive and negative attitudes between e-cigarette users (vapers) and non-e-cigarette-users (non-vapers). Of 6,940,065 e-cigarettes-related tweets, 5,788 were non-commercial tweets related to synthetic cooling agents. The longitudinal trend analysis showed a clear upward trend in discussions. Vapers posted most of the tweets (73.05%, 4,228/5,788). Nearly half (47.87%, 2,771/5,788) held a positive attitude toward synthetic cooling agents, which is significantly higher than those with a negative attitude (19.92%,1,153/5,788) with a P-value < 0.0001. The likelihood of vapers expressing positive attitudes (60.17%, 2,544/4,228) was significantly higher (P < 0.0001) than that of non-vapers (14.55%, 227/1,560). Conversely, negative attitudes from non-vapers (30%, 468/1,560) were significantly (P < 0.0001) higher than vapers (16.2%, 685/4,228). Prevalent topics from positive tweets included "enjoyment of specific vape flavors," "preference for lush ice vapes," and "liking of minty/icy feelings." Major topics from negative tweets included "disliking certain vape flavors" and "dislike of others vaping around them." On Twitter, vapers are more likely to have a positive attitude toward synthetic cooling agents than non-vapers. Our study provides important insights into how the public perceives synthetic cooling agents in e-cigarettes. These insights are crucial for shaping future U.S. Food and Drug Administration (FDA) regulations aimed at safeguarding public health.

Impact of electronic cigarette usage on the onset of respiratory symptoms and COPD among Chinese adults

The prevalence of dual usage and the relatively low cessation rate among e-cigarette (EC) users suggest that ECs have not demonstrated significant effectiveness as a smoking cessation tool. Furthermore, there has been a substantial increase in the prevalence of EC usage in recent years. Therefore, the objective of this study is to investigate the association between EC use and the incidence of respiratory symptoms and chronic obstructive pulmonary disease (COPD). A total of 10,326 participants aged between 20 and 55 years, without any respiratory diseases or COPD, were recruited for the study. These individuals attended employee physical examinations conducted at 16 public hospitals in Hebei province, China from 2015 to 2020. Logistic regression models were utilized to assess the association between EC use and the risk of respiratory symptoms and COPD using risk ratios along with their corresponding 95% confidence intervals. Restricted cubic spline functions were employed to investigate the dose-response non-linear relationship. The robustness of the logistic regression models was evaluated through subgroup analyses, and sensitivity analyses. During the 5-year follow-up period, a total of 1071 incident cases of respiratory symptoms and 146 incident cases of COPD were identified in this cohort study. After adjusting for relevant confounding factors, EC users demonstrated a respective increase in the risk of reporting respiratory symptoms and COPD by 28% and 8%. Furthermore, dual users who used both ECs and combustible cigarettes exhibited an elevated risk of incident respiratory symptoms and COPD by 41% and 18%, respectively, compared to those who had never used non-users of any cigarette products. The association between daily EC consumption and the development of respiratory symptoms, as well as COPD, demonstrated a significant J-shaped pattern. The potential adverse association between the consumption of ECs, particularly when used in combination with combustible cigarettes, and the development of respiratory symptoms and COPD necessitates careful consideration. Policymakers should approach ECs cautiously as a prospective smoking cessation tool.

Acute effects of traditional and electronic cigarettes on palatal blood flow in smokers: A cross-over pilot study

Background

Smoking is a significant health hazard and contributes to cardiovascular and pulmonary diseases. It can increase postoperative complications during oral and maxillofacial surgery due to its topical effect on the oral mucosa. New alternatives to traditional tobacco products are gaining popularity, in particular, electronic cigarettes.

Objectives

This pilot study investigated the acute effects of nicotine-containing and nicotine-free electronic cigarettes on palatal blood flow (PBF), and compared their effects to traditional cigarettes.

Materials and methods

14 medically healthy volunteers (8 males, 6 females, age: 34.7 ± 7.0) were recruited for the study. All patients (N = 14) were requested to smoke nicotine-containing (ECN) and nicotine-free electronic cigarettes (EC0) and a mouthpiece (end of a traditional cigarette) as a control sham smoking blind test (BT). EC users did not smoke a traditional cigarette (TC), resulting in 10 people in the TC group. Palatal blood flow was measured by Laser Speckle Contrast Imager before, immediately after, and 15 min after the exposures. Exhaled carbon monoxide (eCO) and carboxyhemoglobin (COHb) were measured before and immediately after smoking with a piCO+ Smokerlyzer machine.

Results

In all groups, no significant differences were observed in the changes of palatal blood flow between time points. Exhaled carbon monoxide and carboxyhemoglobin were significantly higher in the traditional cigarette (TC) group compared to the nicotine-containing electronic cigarette (ECN) and nicotine-free electronic cigarette (EC0) groups, both before and after the exposure (p < 0.05).

Conclusion

Acute use of either traditional or electronic cigarettes may have minimal impact on palatal blood flow, but additional studies are required to clarify their impact on the mucosa.

Toxicological Aspects Associated with Consumption from Electronic Nicotine Delivery System (ENDS): Focus on Heavy Metals Exposure and Cancer Risk

Tobacco smoking remains one of the leading causes of premature death worldwide. Electronic Nicotine Delivery Systems (ENDSs) are proposed as a tool for smoking cessation. In the last few years, a growing number of different types of ENDSs were launched onto the market. Despite the manufacturing differences, ENDSs can be classified as "liquid e-cigarettes" (e-cigs) equipped with an atomizer that vaporizes a liquid composed of vegetable glycerin (VG), polypropylene glycol (PG), and nicotine, with the possible addition of flavorings; otherwise, the "heated tobacco products" (HTPs) heat tobacco sticks through contact with an electronic heating metal element. The presence of some metals in the heating systems, as well as in solder joints, involves the possibility that heavy metal ions can move from these components to the liquid, or they can be adsorbed into the tobacco stick from the heating blade in the case of HTPs. Recent evidence has indicated the presence of heavy metals in the refill liquids and in the mainstream such as arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), copper (Cu), and lead (Pb). The present review discusses the toxicological aspects associated with the exposition of heavy metals by consumption from ENDSs, focusing on metal carcinogenesis risk.

Impact of electronic cigarette use on the increased risk of diabetes: the Korean Community Health Survey

OBJECTIVES

Only a few studies have solely investigated the health impacts of electronic cigarettes on diabetes while considering the impact of conventional cigarettes. Therefore, this study aimed to examine the effect of electronic cigarette smoking on diabetes in Korean dual smokers, electronic cigarette smokers, conventional cigarette smokers, and non-smokers.

METHODS

Data were obtained from the 2021 and 2022 Korean Community Health Surveys of 460,603 Korean adults. The main independent variable was smoking behavior. Participants were categorized according to their smoking behavior, as dual smokers, electronic cigarette smokers, conventional cigarette smokers, and non-smokers. The dependent variable, the presence of diabetes, was defined by a doctor's diagnosis. Multiple logistic regression analysis was performed to examine the association between smoking behavior and diabetes. Subgroup analyses were also performed to investigate the associations among different socioeconomic groups.

RESULTS

Conventional cigarette smokers had a higher risk of diabetes than did non-smokers (adjusted odds ratio [aOR], 1.22; 95% confidence interval [CI], 1.19 to 1.26). More importantly, those who only vaped electronic cigarettes were at high risk of diabetes (aOR, 1.15; 95% CI, 1.01 to 1.31). Lastly, dual smokers had the highest aOR for diabetes among other smoking behavior groups (aOR, 1.39; 95% CI, 1.22 to 1.58). Dual smoking was associated with the highest risk of diabetes in most subgroups.

CONCLUSIONS

This study suggests that conventional cigarette use and smoking electronic cigarettes negatively impact diabetes, and using both types leads to worse health outcomes. Therefore, cessation of all types of smoking is necessary for a healthy life.

Pain interference among adult dual combustible and electronic tobacco users in terms of perceived barriers for quitting

Electronic cigarette (e-cigarette) use has become increasingly common among combustible cigarette users, and dual use may represent a more severe type of nicotine addiction. Experiencing pain is one prevalent domain that may be important to understand quit processes and behavior among dual users. Although most past research on pain and nicotine/tobacco has focused on combustible cigarette use, initial work on e-cigarette users has found that greater pain severity is associated with higher levels of dependence and negative thinking patterns about e-cigarette use. Yet, there has been no effort to explore the experience of pain among dual users in terms of perceived barriers for quitting combustibles or e-cigarettes. The present study sought to examine pain interference among dual combustible and e-cigarette users in terms of perceived barriers for quitting among 138 (45.9% female; Mage = 35.96 years, SD = 7.16) adult dual users (i.e., users of both combustible cigarette and e-cigarettes). Hierarchical linear regression models indicated that pain interference was significantly associated with both perceived barriers for cessation of combustible cigarettes and perceived barriers for cessation of e-cigarettes. Overall, the present investigation served as an initial evaluation of the role of pain interference in terms of perceived barriers for quitting combustible and e-cigarettes among adult daily dual users. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Nicotine, Flavor, and More: E-Cigarette Aerosols Deliver Toxic Metals

In laboratory experiments, e-cigarettes generated aerosols containing nickel, lead, arsenic, manganese, and other toxic metals. None of the MODs, P ODs, or d-P ODs tested delivered completely metalfree aerosol.

Nicotine and Cardiovascular Health: When Poison is Addictive - a WHF Policy Brief

Nicotine is universally recognized as the primary addictive substance fuelling the continued use of tobacco products, which are responsible for over 8 million deaths annually. In recent years, the popularity of newer recreational nicotine products has surged drastically in many countries, raising health and safety concerns. For decades, the tobacco industry has promoted the myth that nicotine is as harmless as caffeine. Nonetheless, evidence shows that nicotine is far from innocuous, even on its own. In fact, numerous studies have demonstrated that nicotine can harm multiple organs, including the respiratory and cardiovascular systems. Tobacco and recreational nicotine products are commercialized in various types and forms, delivering varying levels of nicotine along with other toxic compounds. These products deliver nicotine in profiles that can initiate and perpetuate addiction, especially in young populations. Notably, some electronic nicotine delivery systems (ENDS) and heated tobacco products (HTP) can deliver concentrations of nicotine that are comparable to those of traditional cigarettes. Despite being regularly advertised as such, ENDS and HTP have demonstrated limited effectiveness as tobacco cessation aids in real-world settings. Furthermore, ENDS have also been associated with an increased risk of cardiovascular disease. In contrast, nicotine replacement therapies (NRT) are proven to be safe and effective medications for tobacco cessation. NRTs are designed to release nicotine in a slow and controlled manner, thereby minimizing the potential for abuse. Moreover, the long-term safety of NRTs has been extensively studied and documented. The vast majority of tobacco and nicotine products available in the market currently contain nicotine derived from tobacco leaves. However, advancements in the chemical synthesis of nicotine have introduced an economically viable alternative source. The tobacco industry has been exploiting synthetic nicotine to circumvent existing tobacco control laws and regulations. The emergence of newer tobacco and recreational nicotine products, along with synthetic nicotine, pose a tangible threat to established tobacco control policies. Nicotine regulations need to be responsive to address these evolving challenges. As such, governments should regulate all tobacco and non-medical nicotine products through a global, comprehensive, and consistent approach in order to safeguard tobacco control progress in past decades.

Electronic cigarette use and chest pain in US adults: Evidence from the PATH study

INTRODUCTION

Electronic cigarettes (e-cigarette) were introduced for smoking cessation/reduction but have also become popular among the youth. Although e-cigarettes contain fewer toxins than combustible cigarettes, their long-term cardiovascular and pulmonary effects remain unknown. We aimed to assess the association between self-reported chest pain and e-cigarette use.

METHODS

We analyzed data from the PATH (Population Assessment of Tobacco and Health) study wave 4 (2016-2018) and wave 5 (2018-2019). Based on questionnaires from wave 4, we categorized tobacco use as: 1) non-use, 2) exclusive e-cigarette use, 3) combustible cigarette use, and 4) dual use. Presence of established cardiovascular disease was examined at wave 4, and participants aged >40 years were asked about chest pain during wave 5. We used binary logistic regression models to determine the association between tobacco exposures and self-reported chest pain.

RESULTS

We evaluated a total of 11254 adults. The rates of chest pain were 1518 out of 7055 non-users, 49 from 208 exclusive e-cigarette users, 1192 from 3722 combustible cigarette users, and 99 out of 269 dual users. In the multivariable models adjusted for relevant covariates, combustible cigarette users (adjusted odds ratio, AOR=1.77; 95% CI: 1.56-2.01) and dual users (AOR=2.22; 95% CI: 1.61-3.05) had higher odds of reporting ever having chest pain, as well as having chest pain in the past 30 days. Conversely, exclusive e-cigarette users had similar odds of reporting chest pain compared to non-users (AOR=1.03; 95% CI: 0.69-1.54) and lower odds than combustible and dual users. In sensitivity analyses, categorizing individuals based on their reported history of cardiovascular disease, overall findings were similar.

CONCLUSIONS

Exclusive e-cigarette use is associated with a lower rate of chest pain compared to combustible cigarette use and dual use.

Impact of Smoking on Salivary Lipid Profile and Oxidative Stress in Young Adults: A Comparative Analysis between Traditional Cigarettes, E-Cigarettes, and Heat-Not-Burn Products

BACKGROUND Smoking nicotine is considered to be one of the most harmful addictions, leading to the development of a number of health complications, including many pathologies in the oral cavity. The aim of this study was to examine the effect of smoking traditional cigarettes, e-cigarettes, and heat-not-burn products on profiles of salivary lipids and lipid peroxidation products in the unstimulated and stimulated saliva of healthy young adults with a smoking habit of up to 3 years. MATERIAL AND METHODS We enrolled 3 groups of 25 smoking patients each and a control group matched for age, gender, and oral status. In saliva collected from patients from the study groups and participants from the control group, the concentrations of sphingolipids: sphingosine, sphinganine, sphingosine-1-phosphate, ceramides, and salivary lipid peroxidation products - malondialdehyde (MDA) and 4-hydroxynonenal (HNE) - were measured. The normality of distribution was assessed using the Shapiro-Wilk test. For comparison of the results, one-way analysis of variance (ANOVA) followed by post hoc Tukey test was used. RESULTS We demonstrated that each type of smoking causes a decrease in the concentration of salivary lipids, and there was an increased concentration of salivary MDA and 4-HNE. CONCLUSIONS Smoking in the initial period of addiction leads to an increase in the concentration of lipid peroxidation products through increased oxidative stress, leading to disturbance of the lipid balance of the oral cavity (eg, due to damage to cell membranes).

Tobacco and menthol flavored nicotine-free electronic cigarettes induced inflammation and dysregulated repair in lung fibroblast and epithelium

BACKGROUND

Electronic cigarette (e-cig) vaping has increased in the past decade in the US, and e-cig use is misleadingly marketed as a safe cessation for quitting smoking. The main constituents in e-liquid are humectants, such as propylene glycol (PG) and vegetable glycerine (VG), but different flavoring chemicals are also used. However, the toxicology profile of flavored e-cigs in the pulmonary tract is lacking. We hypothesized that menthol and tobacco-flavored e-cig (nicotine-free) exposure results in inflammatory responses and dysregulated repair in lung fibroblast and epithelium.

METHOD

We exposed lung fibroblast (HFL-1) and epithelium (BEAS-2B) to Air, PG/VG, menthol flavored, or tobacco-flavored e-cig, and determined the cytotoxicity, inflammation, and wound healing ability in 2D cells and 3D microtissue chip models.

RESULTS

After exposure, HFL-1 showed decreased cell number with increased IL-8 levels in the tobacco flavor group compared to air. BEAS-2B also showed increased IL-8 secretion after PG/VG and tobacco flavor exposure, while menthol flavor exposure showed no change. Both menthol and tobacco-flavored e-cig exposure showed decreased protein abundance of type 1 collagen α 1 (COL1A1), α-smooth-muscle actin (αSMA), and fibronectin as well as decreased gene expression level of αSMA (Acta2) in HFL-1. After tobacco flavor e-cig exposure, HFL-1 mediated wound healing and tissue contractility were inhibited. Furthermore, BEAS-2B exposed to menthol flavor showed significantly decreased tight junction gene expressions, such as CDH1, OCLN, and TJP1.

CONCLUSION

Overall, tobacco-flavored e-cig exposure induces inflammation in both epithelium and fibroblasts, and tobacco-flavored e-cig inhibits wound healing ability in fibroblasts.

Acetal Formation of Flavoring Agents with Propylene Glycol in E-Cigarettes: Impacts on Indoor Partitioning and Thirdhand Exposure

The widespread use of flavored e-cigarettes has led to a significant rise in teenage nicotine use. In e-liquids, the flavor carbonyls can form acetals with unknown chemical and toxicological properties. These acetals can cause adverse health effects on both smokers and nonsmokers through thirdhand exposure. This study aims to explore the impacts of these acetals formed in e-cigarettes on indoor partitioning and thirdhand exposure. Specifically, the acetalization reactions of commonly used flavor carbonyls in laboratory-made e-liquids were monitored using proton nuclear magnetic resonance (1H NMR) spectroscopy. EAS-E Suite and polyparameter linear free energy relationships (PP-LFERs) were employed to estimate the partitioning coefficients for species. Further, a chemical two-dimensional partitioning model was applied to visualize the indoor equilibrium partitioning and estimate the distribution of flavor carbonyls and their acetals in the gas phase, aerosol phase, and surface reservoirs. Our results demonstrate that a substantial fraction of carbonyls were converted into acetals in e-liquids and their chemical partitioning was significantly influenced. This study shows that acetalization is a determinant factor in the exposure and toxicology of harmful carbonyl flavorings, with its impact extending to both direct exposure to smokers and involuntary exposure to nonsmokers.

Metal Concentrations in E-Cigarette Aerosol Samples: A Comparison by Device Type and Flavor

BACKGROUND

The rapid evolution of electronic cigarette (e-cigarette) products warrants surveillance of the differences in exposure across device types-modifiable devices (MODs), cartridge ("pod")-containing devices (PODs), disposable PODs (d-PODs)-and flavors of the products available on the market.

OBJECTIVE

This study aimed to measure and compare metal aerosol concentrations by device type and common flavors.

METHODS

We collected aerosol from 104 MODs, 67 PODs (four brands: JUUL, Bo, Suorin, PHIX), and 23 d-PODs (three brands: ZPOD, Bidi, Stig) via droplet deposition in a series of conical pipette tips. Metals and metalloids [aluminum (Al), arsenic (As), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), antimony (Sb), tin (Sn), and zinc (Zn)] were measured using inductively coupled plasma mass spectrometry (ICP-MS), results were log-transformed for statistical analysis, and concentrations are reported in aerosol units (mg / m 3 ).

RESULTS

Of the 12 elements analyzed, concentrations were statistically significantly higher in MOD devices, except for Co and Ni, which were higher in PODs and d-PODs. Of the POD brands analyzed, PHIX had the highest median concentrations among four metals (Al, Ni, Pb, and Sn) compared to the rest of the POD brands. According to POD flavor, seven metals were three to seven orders of magnitude higher in tobacco-flavored aerosol compared to those in mint and mango flavors. Among the d-POD brands, concentrations of four metals (Al, Cu, Ni, and Pb) were higher in the ZPOD brand than in Bidi Stick and Stig devices. According to d-POD flavor, only Cr concentrations were found to be statistically significantly higher in mint than tobacco-flavored d-PODs.

DISCUSSION

We observed wide variability in aerosol metal concentrations within and between the different e-cigarette device types, brands, and flavors. Overall, MOD devices generated aerosols with higher metal concentrations than PODs and d-PODs, and tobacco-flavored aerosols contained the highest metal concentrations. Continued research is needed to evaluate additional factors (i.e., nicotine type) that contribute to metal exposure from new and emerging e-cigarette devices in order to inform policy. https://doi.org/10.1289/EHP11921.

E-Cigarettes and Associated Health Risks: An Update on Cancer Potential

The potential cancer risk associated with electronic-cigarette (e-cigarette) use is ongoing and remains a subject of debate. E-Cigarettes work by heating a liquid that usually contains nicotine, flavorings, and other chemicals. When the liquid is heated, users inhale an aerosol into their lungs. While e-cigarettes are generally considered less harmful than traditional tobacco products, they still contain potentially harmful chemicals, which can damage DNA and lead to cancer. Several studies have investigated the potential cancer risk associated with e-cigarette use, while other studies have suggested that e-cigarette aerosol may contain carcinogenic chemicals that could increase the risk of lung and bladder cancer in humans. However, these studies are limited in their scope and do not provide conclusive evidence. Overall, the long-term cancer risk associated with e-cigarette use remains uncertain, more research is needed to fully understand the potential risks and benefits of e-cigarettes. However, this review will allow the investigator to get more recent updates about e-cigarettes.

Electronic Cigarette Use and Myocardial Infarction

BACKGROUND

Current electronic cigarettes (e-cigarettes) is associated with myocardial infarction, controlling whether the subjects smoke cigarettes. However, no studies have been conducted on subjects who never smoked cigarettes. This study aimed to determine the association between e-cigarette use and myocardial infarction among subjects who have never smoked cigarettes.

METHODS

The National Health Interview Survey (NHIS) data from 2014 to 2021 was used to evaluate the relationship between e-cigarette use and myocardial infarction in subjects who have never smoked cigarettes after adjusting for risk factors, including age, sex, diabetes, hypertension, hypercholesterolemia, and obesity/overweight, using logistic regression.

RESULTS

 A total of 139,697 subjects were never users, and 1,237 subjects were current e-cigarette users. E-cigarette users were significantly younger than never users. E-cigarette users were less likely to be female (40% vs. 60%, p <0.01), or have diabetes (3% vs. 10%, p <0.01), have hypertension (11% vs. 32%, p <0.01), have hypercholesterolemia (8% vs. 27%, p <0.01), or be overweight or obese (56% vs. 65%, p <0.01) compared to never users. The current e-cigarette users had a 2.6-fold increase in the odds of having a myocardial infarction (OR 2.62, 95% CI 1.44-4.77; p <0.01) after adjusting for sex, age, hypertension, diabetes, hypercholesterolemia, and obesity/overweight.  Conclusions: This study suggests that current e-cigarette use increases the risks of cardiovascular disease, including myocardial infarction and stroke, in subjects who never smoked cigarettes. Further longitudinal studies are needed to confirm the results of this study.

Adverse Biophysical Impact of e-Cigarette Flavors on Pulmonary Surfactant

The attractiveness and abundance of flavors are primary factors eliciting youth to use e-cigarettes. Emerging studies in recent years revealed the adverse health impact of e-cigarette flavoring chemicals, including disruption of the biophysical function of pulmonary surfactants in the lung. Nevertheless, a comprehensive understanding of the biophysical impact of various flavoring chemicals is still lacking. We used constrained drop surfactometry as a new alternative method to study the biophysical impact of flavored e-cigarette aerosols on an animal-derived natural pulmonary surfactant. The dose of exposure to e-cigarette aerosols was quantified with a quartz crystal microbalance, and alterations to the ultrastructure of the surfactant film were visualized using atomic force microscopy. We have systematically studied eight representative flavoring chemicals (benzyl alcohol, menthol, maltol, ethyl maltol, vanillin, ethyl vanillin, ethyl acetate, and ethyl butyrate) and six popular recombinant flavors (coffee, vanilla, tobacco, cotton candy, menthol/mint, and chocolate). Our results suggested a flavor-dependent inhibitory effect of e-cigarette aerosols on the biophysical properties of the pulmonary surfactant. A qualitative phase diagram was proposed to predict the hazardous potential of various flavoring chemicals. These results provide novel implications in understanding the environmental, health, and safety impacts of e-cigarette aerosols and may contribute to better regulation of e-cigarette products.

Photometric Monitoring of Electronic Cigarette Puff Topography

To study and monitor the adverse health consequences of using electronic cigarettes, a user's puff topography, which are quantification parameters of the user's vaping habits, plays a central role. In this work, we introduce a topography sensor to measure the mass of total particulate matter generated in every puff and to estimate the nicotine yield. The sensor is compact and low-cost, and is integrated into the electronic cigarette device to promptly and conveniently monitor the user's daily puff topography. The topography sensor is comprised of a photometric sensor and a pressure sensor. The photometric sensor measures the mass concentration of the aerosol, based on scattering of near-infrared light from airborne particles, while the pressure sensor measures the flow rate. The topography sensor was tested under various conditions including a wide range of atomizer power, puff duration, and inhalation pressure. The sensor's accuracy was validated by comparing the sensor's readings with reference measurements, and the results matched closely with the trends reported by existing studies on electronic cigarettes. An example application for tracking a user's puff topography was also demonstrated. Our topography sensor holds great promise in mitigating the health risks of vaping, and in promoting quality control of electronic cigarette products.

Public perceptions of synthetic cooling agents in electronic cigarettes on Twitter

Amid a potential menthol ban, electronic cigarette (e-cigarette) companies are incorporating synthetic cooling agents like WS-3 and WS-23 to replicate menthol/mint sensations. This study examines public views on synthetic cooling agents in e-cigarettes via Twitter data. From May 2021 to March 2023, we used Twitter Streaming API, to collect tweets related to synthetic cooling agents with keywords such as 'WS-23,' 'ice,' and 'frozen.' Two deep learning roBERTa models, classified attitudes expressed in tweets about synthetic cooling agents and identified e-cigarette users. The BERTopic deep-learning model identified major topics of positive and negative tweets. Two proportion Z-tests were used to compare the proportions of positive and negative attitudes between e-cigarette users (vapers) and non-e-cigarette-users (non-vapers). Of 6,940,065 e-cigarettes related tweets, 5,788 non-commercial tweets related to synthetic cooling agents. The longitudinal trend analysis showed a clear upwards trend in discussions. Vapers posted most of the tweets (73.05%, 4,228/5,788). Nearly half (47.87%, 2,771/5,788) held a positive attitude toward synthetic cooling agents, which is significantly higher than those with a negative attitude (19.92%,1,153/5,788) with a P-value < 0.0001. The likelihood of Vapers expressing positive attitudes (60.17%, 2,544/4,228) was significantly higher (P < 0.0001) than that from non-vapers (14.55%, 227/1,560). Conversely, negative attitudes from non-vapers (30%, 468/1,560) was significantly (P < 0.0001) higher than vapers (16.2%, 685/4,228). Prevalent topics from positive tweets included "enjoyment of specific vape flavors," "preference for lush ice vapes," and "liking of minty/icy feelings." Major topics from negative tweets included "disliking certain vape flavors" and "dislike of others vaping around them." On Twitter, vapers are more likely to have a positive attitude toward synthetic cooling agents than non-vapers. Our study provides important insights into how the public perceives synthetic cooling agents in e-cigarettes, insights that are crucial for shaping future FDA regulations aimed at safeguarding public health.

Cross-sectional study on public health knowledge among first-year university students in Japan: Implications for educators and educational institutions

In recent years, there have been increasing knowledge gaps and biases in public health information. This has become especially evident during the COVID-19 pandemic and has contributed to the spread of misinformation. With constant exposure to disinformation and misinformation through television, the internet, and social media, even university students studying healthcare-related subjects lack accurate public health knowledge. This study aimed to assess university students' knowledge levels of basic public health topics before they started their specialized education. Participants in this cross-sectional study were first-year students from medical schools, health-related colleges, and liberal arts colleges. A self-administered electronic survey was conducted from April to May 2021 at a private university in Japan, comprising six colleges with seven programs. Data analysis, conducted from June to December 2022, included students' self-reported public health knowledge, sources of information, and self-assessment of knowledge levels. Among the 1,562 students who received the questionnaire, 549 (192 male [35%], 353 female [64.3%], and 4 undisclosed [0.7%]) responded to one question (participants' response rate for each question; 59.6%-100%). The results showed that students had limited public health knowledge, especially in sexual health topics, and 10% of students reported not learning in class before university admission the following 11 topics: two on Alcohol, Tobacco, and Other Drugs; eight on Growth, Development, and Sexual Health; and one on Personal and Community Health. These results indicate significant knowledge gaps and biases, as well as gender gaps, in public health education, especially in the area of sexual health, which may help educators and educational institutions to better understand and prepare for further specialized education. The findings also suggest a need to supplement and reinforce the foundation of public health knowledge for healthcare majors at the time of university admission.

Electronic nicotine delivery systems (ENDS): A convenient means of smoking?

Electronic nicotine delivery systems (ENDS), which are becoming increasingly popular in many parts of the world, have recently become more sophisticated in terms of their more active content and better controlled vaporisation. This review begins by describing how cigarette smoking led to the development of ENDS as a means of combatting nicotine addiction. ENDS are usually categorised as belonging to one of only three main generations, but a fourth has been added in order to differentiate the latest, most powerful, most advanced and innovative that have improved heating efficiency. Descriptions of the principal substances contained in ENDS are followed by considerations concerning the risk of toxicity due to the presence of albeit low concentrations of such a variety of compounds inhaled over a long time, and the increasingly widespread use of ENDS as a means of smoking illicit drugs. We also review the most widely used pharmacotherapeutic approaches to smoking cessation, and recent epidemiological data showing that ENDS can help some people to stop smoking. However, in order to ensure their appropriate regulation, there is a need for higher-quality evidence concerning the health effects and safety of ENDS, and their effectiveness in discouraging tobacco smoking.

E-cigarette awareness and use, among adult residents in Shanghai, China

INTRODUCTION

The widespread popularity of e-cigarettes is considered an important public health concern. However, only some studies have investigated the prevalence of e-cigarette use in Shanghai, China. Research on the perceived harmfulness of e-cigarettes and public support for e-cigarette regulations in China is limited. This study aimed to estimate e-cigarette awareness, prevalence, and associated factors among adults in Shanghai, China.

METHODS

This study used data from a representative survey conducted in Shanghai, China, in 2019. The survey was conducted at 64 surveillance points in Shanghai, China, using a multistage, stratified, cluster-randomized sampling design, recruiting community-based Chinese adults aged ≥15 years. Based on the principles outlined in the Global Adult Tobacco Survey (GATS) China Project, data were collected by conducting face-to-face interviews in households. Of the 3200 selected households, 3060 people completed the individual survey. The overall response rate was 97.4%.

RESULTS

In all, 72.3% of the respondents had heard of e-cigarettes. The respondents who had used e-cigarettes at some point in their life, used them in the last 12 months, and used them currently were 5.8%, 2.6%, and 1.3%, respectively. Among adult residents who had heard of e-cigarettes, 38.2% thought they were less harmful than traditional cigarettes. The respondents who perceived e-cigarettes as more harmful than traditional cigarettes were less likely to have ever used e-cigarettes (AOR=0.2; 95% CI: 0.1-0.5, p=0.0015) and more likely to support incorporating e-cigarettes into the regulation of smoking control (AOR=3.9; 95% CI: 1.8-8.6, p=0.0008).

CONCLUSIONS

Our findings reveal that the awareness about e-cigarettes was high, and the prevalence of e-cigarette use was similar to the findings from previous studies in China. The harmful perception of e-cigarettes warrants further attention from public health practitioners.

Estimation of Health Risks Caused by Metals Contained in E-Cigarette Aerosol through Passive Vaping

It is expected that secondary exposure to e-cigarette aerosol (passive vaping) will soon become an issue of public health. Passive vaping inhales e-cigarette aerosol containing similar harmful substances as active vaping. However, parallel studies on passive vaping are minimal. Therefore, there is a need for passive vaping-related health risk studies to assess the impact of vaping on public health. This research conducted a series of experiments in a room using a puffing machine and the Mobile Aerosol Lung Deposition Apparatus (MALDA) to study e-cigarette aerosol respiratory deposition through passive vaping. The experimental data acquired were applied to estimate the deposited mass and health risks caused by toxic metals contained in e-cigarette aerosol. Five popular e-cigarette products were used in this study to generate e-cigarette aerosol for deposition experiments. In addition, size-segregated e-cigarette aerosol samples were collected, and metal compositions in the e-cigarette aerosol were analyzed. Results obtained showed that estimated non-cancer risks were all acceptable, with hazard quotient and hazard index all less than 1.0. The calculated cancer risks were also found acceptable, with lifetime excess cancer risk generally less than 1E-6. Therefore, the e-cigarettes tested and the passive vaping exposure scenarios studied do not seem to induce any potential for metal-related respiratory health effects.

Ethics and ENDS

As debate persists over regulating electronic nicotine delivery systems (ENDS), those favouring liberal ENDS policies have advanced rights-based arguments privileging harm reduction to people who smoke over harm prevention to children and never-smokers. Recent ethical arguments advocate regulating ENDS to prioritise their harm reduction potential for people who currently smoke over any future harm to young never-smokers. In this article, we critically assess these arguments, in particular, the assumption that ethical arguments for prioritising the interests of young people do not apply to ENDS. We argue that, when the appropriate comparators are used, it is not clear the weight of ethical argument tips in favour of those who currently smoke and against young never-smokers. We also assert that arguments from a resource prioritisation context are not appropriate for analysing ENDS regulation, because ENDS are not a scarce resource. Further, we reject utilitarian arguments regarding maximising net population health benefits, as these do not adequately consider vulnerable groups' rights, or address the population distribution of benefits and harms. Lastly, we argue that one-directional considerations of harm reduction do not recognise that ENDS potentially increase harm to those who do not smoke and who would not otherwise have initiated nicotine use.

Electronic Nicotine Delivery System: End to Smoking or Just a New Fancy Cigarette

Smoking and tobacco chewing are the predominant causes of oral cancer. Tobacco is the second-most widely consumed psychoactive substance. There are numerous ways to quit smoking, of which one is electronic cigarettes (e-cigarettes). E-cigarette use is a brand-new, global trend. E-cigarette is a battery-operated device that heats a liquid to create a vapor that the consumer inhales. Several countries have acknowledged that the first step toward electronic nicotine delivery system (ENDS) management is a precise classification of ENDS within the limits of current legislation. Countries have currently categorized ENDS into four generations. People's perceptions about tobacco products have altered recently as a consequence of the advertising of ENDS. The likelihood of starting to smoke cigarettes was four times higher in adolescents who used ENDS, and the probability of quitting was reduced and often prolonged in those who used ENDS. In addition, ENDS normalizes smoking-like actions including inhaling in and exhaling smoke. Adverse marketing via geographic locations and social media platforms, as well as nicotine's irreversible effects on growing adolescent and young adult brains that predispose individuals to addicted behaviors, may be responsible for their rising appeal among teenagers. Despite this, ENDS use has risen among young individuals who have never smoked and undoubtedly face more health risks than those who do not use ENDS. The oral cavity is the first to encounter ENDS in individuals and where it initially affects the human system. As a known contributor to cardiovascular diseases, neurological conditions, and cancers, nicotine seems to be a serious cause for concern. This review provides a concise summary of the research on the components, mode of action, applications, and effects of e-cigarettes on oral as well as systemic systems.

The toxic effects of electronic cigarette aerosol and cigarette smoke on cardiovascular, gastrointestinal and renal systems in mice

Electronic cigarette (EC) has been suggested to be less harmful than cigarette smoking, but the research on the full extent of their harm reduction potential is still lacking. This study aimed to evaluate the influence of EC aerosol and cigarette smoke (CS) on cardiovascular, gastrointestinal, and renal functions in mice after prolonged exposure. Forty-eight C57BL/6J male mice were randomly grouped and then exposed to fresh air (control), mung bean-flavored EC aerosol with low and high dose (EC1L, 6 mg/kg; EC1H, 12 mg/kg), watermelon-flavored EC aerosol with low and high dose (EC2L, 6 mg/kg; EC2H, 12 mg/kg), and finally a cigarette smoke (CS, 6 mg/kg), respectively. After 10 weeks of exposure, the heart rate increased for both the EC and CS groups, and the effect of CS on blood oxygen saturation was significantly higher than that of the EC group (P < 0.01). Proteomic analysis of the heart tissue showed that the overlapped differential expression protein from the EC and CS exposures was Crip2. For the gastrointestinal system, oral mucosa was significantly damaged in CS group. Compare with CS, EC had significantly fewer negative effects on most of the indictors which focused on in this study.

Impacts of cigarette smoking on blood circulation: do we need a new approach to blood donor selection?

Smoking is a major public health problem and is considered the leading cause of preventable death worldwide. Gas-phase smoke carries bioactive substances and toxic compounds, affecting human health and reducing life spans. The negative effects of smoking on red blood cell (RBC) quality include destroying RBCs and increasing carboxy hemoglobin (COHb). Smoking increases the concentrations of heavy metals such as cadmium (Cd) and lead (Pb) in the blood. Moreover, tobacco smoking has been found to be associated with heightened platelet (PLT)-dependent thrombin level which will induce a prothrombotic state. Smoking may affect the blood circulation of donors, and subsequently the blood components, and ultimately the recipients of transfusion. Nevertheless, there are no restrictions on smoking for volunteer blood donor screenings currently. We reviewed the articles about the influence of smoking on smokers' blood circulation as well as the impact of donated blood products on transfusion when these smokers act as blood donors. We aim to attract blood collection centers' attention to strengthen the management of blood donors who smoke, avoiding their use in massive transfusion protocol and susceptible recipients, especially pediatric ones.

The cardiovascular consequences of electronic cigarette smoking: a narrative review

INTRODUCTION

E-cigarettes have emerged as a popular alternative to traditional tobacco smoking in recent years. Despite their growing popularity, concerns have arisen regarding the cardiovascular implications of e-cigarette use.

AREAS COVERED

This narrative review aims to highlight the latest evidence on the impact of e-cigarettes on cardiovascular health.

EXPERT OPINION

Numerous studies have demonstrated that e-cigarette use can lead to acute adverse cardiovascular effects. Inhalation of e-cigarette aerosols exposes users to a wide range of potentially harmful substances that have been implicated in critical pathophysiologic pathways of cardiovascular disease, namely endothelial dysfunction, oxidative stress, inflammation, sympathetic overdrive, and arterial stiffness. While long-term epidemiological studies specifically focusing on the cardiovascular effects of e-cigarettes are still relatively scarce, early evidence suggests a potential association between e-cigarette use and an increased risk of adverse cardiovascular events. However, it is essential to recognize that e-cigarettes are relatively new products, and the full extent of their long-term cardiovascular impact has not been fully elucidated. In the meantime, promoting tobacco cessation strategies that are evidence-based and regulated, along with rigorous monitoring of e-cigarette use patterns and associated health outcomes, are essential steps in safeguarding cardiovascular health in the face of this emerging public health challenge.