Secondhand exposure to e-cigarette aerosols among smokers: A cross-sectional study in six European countries of the EUREST-PLUS ITC Europe Surveys

The inclusion of e-cigarettes and heated tobacco products in smoke-free home and car rules: A cross-sectional survey of adults in Armenia and Georgia

INTRODUCTION

Understanding who includes e-cigarettes and heated tobacco products (HTPs) in smoke-free home or car rules could inform public health interventions, particularly in countries with high smoking prevalence and recently implemented national smoke-free laws, like Armenia and Georgia.

METHODS

In 2022, we conducted a cross-sectional survey among 1468 adults in 28 Armenian and Georgian communities (mean age=42.92 years; 51.4% female, 31.6% past-month smoking). Multilevel regression (accounting for clustering within communities; adjusted for sociodemographics and cigarette use) examined e-cigarette/HTP perceptions (risk, social acceptability) and use intentions in relation to: 1) including e-cigarettes/HTPs in home and car rules among participants with home and car rules, respectively (logistic regressions); and 2) intention to include e-cigarettes/HTPs in home rules (linear regression, 1 = 'not at all' to 7 = 'extremely') among those without home rules.

RESULTS

Overall, 72.9% (n=1070) had home rules, 86.5% of whom included e-cigarettes/HTPs; 33.9% (n=498) had car rules, 81.3% of whom included e-cigarettes/HTPs. Greater perceived e-cigarette/HTP risk was associated with including e-cigarettes/HTPs in home rules (AOR=1.28; 95% CI: 1.08-1.50) and car rules (AOR=1.46; 95% CI: 1.14-1.87) and next-year intentions to include e-cigarettes/HTPs in home rules (β=0.38; 95% CI: 0.25-0.50). Lower e-cigarette/HTP use intentions were associated with including e-cigarettes/HTPs in home rules (AOR=0.75; 95% CI: 0.63-0.88). While perceived social acceptability was unassociated with the outcomes, other social influences were: having children and no other household smokers was associated with including e-cigarettes/HTPs in car rules, and having children was associated with intent to include e-cigarettes/HTPs in home rules.

CONCLUSIONS

Interventions to address gaps in home and car rules might target e-cigarette/HTP risk perceptions.

Comparative systematic review on the safety of e-cigarettes and conventional cigarettes

BACKGROUND

This systematic review evaluated the health risks of electronic cigarettes (e-cigarettes) compared to traditional cigarettes. It examines various studies and research on the subject to provide a comprehensive analysis of potential health risks associated with both smoking methods.

METHODS

The systematic review, incorporating searches in PubMed, Scopus, Web of Science, and the Cochrane Library up to July 2023, examines the results obtained in relevant studies, and provides a critical discussion of the results.

RESULTS

E-cigarettes exhibit reduced exposure to harmful toxins compared to traditional cigarettes.

CONCLUSION

However, concerns persist regarding respiratory irritation and potential health risks, especially among youth, emphasizing the need for comprehensive, long-term research and protective legislation.

Exposure to secondhand aerosol from electronic cigarettes at homes: A real-life study in four European countries

Electronic cigarette (e-cigarette) use emits potentially hazardous compounds and deteriorates indoor air quality. Home is a place where e-cigarettes may frequently be used amid its increasing prohibition in public places. This study assessed the real-life scenario of bystanders' exposure to secondhand e-cigarette aerosol (SHA) at home. A one-week observational study was conducted within the TackSHS project in four countries (Greece, Italy, Spain, and the United Kingdom) in 2019 including: 1) homes of e-cigarette users living together with a non-user/non-smoker; and 2) control homes with no smokers nor e-cigarette users. Indoor airborne nicotine, PM2.5, and PM1.0 concentrations were measured as environmental markers of SHA. Biomarkers, including nicotine and its metabolites, tobacco-specific nitrosamines, propanediol, glycerol, and metals were measured in participants' saliva and urine samples. E-cigarette use characteristics, such as e-cigarette refill liquid's nicotine concentration, e-cigarette type, place of e-cigarette use at home, and frequency of ventilation, were also collected. A total of 29 e-cigarette users' homes and 21 control homes were included. The results showed that the seven-day concentrations of airborne nicotine were quantifiable in 21 (72.4 %) out of 29 e-cigarette users' homes; overall, they were quite low (geometric mean: 0.01 μg/m3; 95 % CI: 0.01-0.02 μg/m3) and were all below the limit of quantification in control homes. Seven-day concentrations of PM2.5 and PM1.0 in e-cigarette and control homes were similar. Airborne nicotine and PM concentrations did not differ according to different e-cigarette use characteristics. Non-users residing with e-cigarette users had low but significantly higher levels of cotinine, 3'-OH-cotinine and 1,2-propanediol in saliva, and cobalt in urine than non-users living in control homes. In conclusion, e-cigarette use at home created bystanders' exposure to SHA regardless of the e-cigarette use characteristics. Further studies are warranted to assess the implications of SHA exposure for smoke-free policy.

Influence of E-Liquid Humectants, Nicotine, and Flavorings on Aerosol Particle Size Distribution and Implications for Modeling Respiratory Deposition

Electronic cigarette, or vaping, products are used to heat an e-liquid to form an aerosol (liquid droplets suspended in gas) that the user inhales; a portion of this aerosol deposits in their respiratory tract and the remainder is exhaled, thereby potentially creating opportunity for secondhand exposure to bystanders (e.g., in homes, automobiles, and workplaces). Particle size, a critical factor in respiratory deposition (and therefore potential for secondhand exposure), could be influenced by e-liquid composition. Hence, the purposes of this study were to (1) test the influence of laboratory-prepared e-liquid composition [ratio of propylene glycol (PG) to vegetable glycerin (VG) humectants, nicotine, and flavorings] on particle size distribution and (2) model respiratory dosimetry. All e-liquids were aerosolized using a second-generation reference e-cigarette. We measured particle size distribution based on mass using a low-flow cascade impactor (LFCI) and size distribution based on number using real-time mobility sizers. Mass median aerodynamic diameters (MMADs) of aerosol from e-liquids that contained only humectants were significantly larger compared with e-liquids that contained flavorings or nicotine (p = 0.005). Humectant ratio significantly influenced MMADs; all aerosols from e-liquids prepared with 70:30 PG:VG were significantly larger compared with e-liquids prepared with 30:70 PG:VG (p = 0.017). In contrast to the LFCI approach, the high dilution and sampling flow rate of a fast mobility particle sizer strongly influenced particle size measurements (i.e., all calculated MMAD values were < 75 nm). Dosimetry modeling using LFCI data indicated that a portion of inhaled particles will deposit throughout the respiratory tract, though statistical differences in aerosol MMADs among e-liquid formulations did not translate into large differences in deposition estimates. A portion of inhaled aerosol will be exhaled and could be a source for secondhand exposure. Use of laboratory-prepared e-liquids and a reference e-cigarette to standardize aerosol generation and a LFCI to measure particle size distribution without dilution represents an improved method to characterize physical properties of volatile aerosol particles and permitted determination of MMAD values more representative of e-cigarette aerosol in situ, which in turn, can help to improve dose modeling for users and bystanders.

Environmental and individual exposure to secondhand aerosol of electronic cigarettes in confined spaces: Results from the TackSHS Project†

Secondhand electronic cigarette (e-cigarette) aerosol (SHA) might impair indoor air quality and expose bystanders. This study aims to investigate exposure to SHA in controlled conditions of enclosed settings simulating real-world scenario. An experiment was performed in a car and in a room, in which SHA was generated during a 30-minute ad libitum use of an e-cigarette. The experiment was replicated on five consecutive days in each setting. We measured PM_2.5 , airborne nicotine concentrations, and biomarkers of exposure to SHA, such as nicotine metabolites, tobacco-specific nitrosamines, propylene glycol, and glycerol in bystanders' saliva samples before, during, and after the exposure period. Self-reported health symptoms related to exposure to SHA were also recorded. The results showed that the highest median PM_2.5 concentration was recorded during the exposure period, being 21 µg/m³ in the room setting and 16 µg/m³ in the car setting-about twofold increase compared to the baseline. Most concentrations of the airborne nicotine and all biomarkers were below the limit of quantification in both settings. Bystanders in both settings experienced some short-term irritation symptoms, expressed as dry throat, nose, eyes, and phlegm. In conclusion, short-term use of an e-cigarette in confined spaces increased indoor PM_2.5 level and caused some irritation symptoms in bystanders.

How widespread is electronic cigarette use in outdoor settings? A field check from the TackSHS project in 11 European countries

Exposure to secondhand aerosol from electronic cigarettes (e-cigarettes) may pose harms to bystanders, but they are used in many indoor settings. Less evidence exists on e-cigarette use in outdoor settings. This study aims to assess the use of e-cigarettes in outdoor settings in Europe. A cross-sectional study was conducted at the entrances of primary schools (N = 200), children's playgrounds (N = 200), and outdoor hospitality venues (N = 220) during 2017-2018 in major cities of 11 European countries. We performed 30-min observations and recorded e-cigarette use at three-time points: at 0 min, 15 min, and 30 min. We described the number and proportion of settings with e-cigarette use observed at any of the three-time points according to country and other contextual variables. Results showed that there were 22 (11.0%) school entrances, eight (4.0%) playgrounds, and 47 (21.3%) outdoor hospitality venues where e-cigarette use was observed at any time point. School entrances and outdoor hospitality venues with observed e-cigarette use were more frequently found in countries with a higher prevalence (≥1.4%) of e-cigarette use (school entrances: 18.0% vs. 4.0%; p = 0.002, outdoor hospitality venues: 26.7% vs. 15.0%, p = 0.036). In conclusion, the outdoor setting with the highest visibility of e-cigarette use was outdoor areas of hospitality venues. Although still limited, e-cigarettes were also used in outdoor settings frequented by children. Governments should consider measures to restrict e-cigarette use outdoors to protect the health of bystanders, particularly in areas where children may be present.

Use of electronic cigarettes and secondhand exposure to their aerosols are associated with asthma symptoms among adolescents: a cross-sectional study

Background

Globally, a surge in electronic cigarette (e-cigarette) use has been observed in recent years, with youth being the most susceptible group. Given their recent emergence, studies assessing the health consequences of using e-cigarettes and exposure to their secondhand aerosols (SHA) are limited. Hence, this study sought to assess associations between e-cigarette use and household exposure to SHA from e-cigarettes with asthma symptoms among adolescents.

Methods

A school-based cross-sectional study was conducted by enrolling high school students (n = 1565; aged 16–19 years) in Kuwait. Participants self-completed a questionnaire on tobacco products use (e-cigarettes and cigarettes) and asthma symptoms. Current e-cigarette use and cigarette smoking were defined as any use in the past 30 days. Household exposure to SHA from e-cigarettes in the past 7 days was reported as none (0 days), infrequent (1–2 days), and frequent (≥ 3 days). Asthma symptoms included current (past 12 months) wheeze, current asthma (history of clinical diagnosis and current wheeze and/or medication use), and current symptoms of uncontrolled asthma (≥ 4 attacks of wheeze, ≥ 1 night per week sleep disturbance from wheeze, and/or wheeze affecting speech). Associations were assessed using Poisson regression with robust variance estimation, and adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) were estimated.

Results

Among the analytical study sample (n = 1345), current e-cigarette use and cigarette smoking was reported by 369 (27.4%) and 358 (26.6%) participants, respectively. Compared to never e-cigarette users and never cigarette smokers, current e-cigarette users with no history of cigarette smoking had increased prevalence of current wheeze (aPR = 1.54, 95% CI 1.01–2.45) and current asthma (aPR = 1.85, 95% CI 1.03–3.41). Moreover, the frequency of exposure to household SHA from e-cigarettes was associated with asthma symptoms. For example, compared to those with no exposure to household SHA, frequent exposure to household SHA was associated with current wheeze (aPR = 1.30, 95% CI 1.04–1.59), current asthma (aPR = 1.56, 95% CI 1.13–2.16), and current uncontrolled asthma symptoms (aPR = 1.88, 95% CI 1.35–2.62).

Conclusions

E-cigarette use and their household SHA exposure were independently associated with asthma symptoms among adolescents. Hence, such observations indicate that e-cigarette use and passive exposure to their aerosols negatively impact respiratory health among adolescents.

Exposure to secondhand aerosol of electronic cigarettes in indoor settings in 12 European countries: data from the TackSHS survey

INTRODUCTION

Exposure to secondhand aerosol from e-cigarette (SHA) may pose harmful effects to bystanders. This study aims to investigate the prevalence, duration and determinants of SHA exposure in various indoor settings in 12 European countries.

METHODS

In 2017-2018, we conducted a cross-sectional study, the TackSHS survey, on a representative sample of the population aged ≥15 years in 12 European countries (Bulgaria, England, France, Germany, Greece, Ireland, Italy, Latvia, Poland, Portugal, Romania and Spain). We described the prevalence and duration of exposure to SHA in several indoor settings among 11 604 e-cigarette non-users. Individual-level and country-level characteristics associated with SHA exposure were also explored using multilevel logistic regression analyses.

RESULTS

Overall, 16.0% of e-cigarette non-users were exposed to SHA in any indoor setting at least weekly, ranging from 4.3% in Spain to 29.6% in England. The median duration of SHA exposure among those who were exposed was 43 min/day. 'Other indoor settings' (eg, bar and restaurant) was reported as the place where most of e-cigarette non-users were exposed (8.3%), followed by workplace/educational venues (6.4%), home (5.8%), public transportation (3.5%) and private transportation (2.7%). SHA exposure was more likely to occur in certain groups of non-users: men, younger age groups, those with higher level of education, e-cigarette past users, current smokers, those perceiving SHA harmless and living in countries with a higher e-cigarette use prevalence.

CONCLUSIONS

We found inequalities of SHA exposure across and within European countries. Governments should consider extending their tobacco smoke-free legislation to e-cigarettes to protect bystanders, particularly vulnerable populations such as young people.

TRIAL REGISTRATION NUMBER

NCT02928536.

Regulation of Electronic Cigarette Use in Public and Private Areas in 48 Countries Within the WHO European Region: A Survey to In-country Informants

Background

The objective of this study is to describe the legislation regulating the use of electronic cigarettes (e-cigarettes) in various places in European countries.

Methods

A survey among experts from all countries of the World Health Organization (WHO) European Region was conducted in 2018. We collected and described data on legislation regulating e-cigarette use indoors and outdoors in public and private places, the level of difficulties in adopting the legislation, and the public support and compliance. Factors associated with the legislation adoption were identified with Poisson and linear regression analyses.

Results

Out of 48 countries, 58.3% had legislation on e-cigarette use at the national level. Education facilities were the most regulated place (58.3% of countries), while private areas (eg, homes, cars) were the least regulated ones (39.6%). A third of countries regulated e-cigarette use indoors. Difficulty and support in adopting the national legislation and its compliance were all at a moderate level. Countries’ smoking prevalence and income levels were linked to legislation adoption.

Conclusions

Although most WHO European Region countries had introduced e-cigarette use legislation at the national level, only a few of the legislation protect bystanders in indoor settings.