Measuring secondhand smoke in homes in Malaysia: A feasibility study comparing indoor fine particulate (PM2.5) concentrations following an educational feedback intervention to create smoke-free homes during the COVID-19 pandemic.

INTRODUCTION: Extensive regulations have been introduced to reduce secondhand smoke (SHS) exposure among non-smokers in Malaysia. However, there is still a need to encourage behavior change of smokers in relation to making homes smoke-free. This feasibility study aimed to use low-cost air pollution monitors to quantify SHS concentrations in Malaysian households and to explore the practicality of using personalized feedback in educating families to make their homes smoke-free. METHODS: A total of 35 smokers in three states in Malaysia were recruited via snowball and convenience sampling methods. Indoor fine particulate (PM2.5) concentrations in participants' homes were measured for 7 days before and after educational intervention using a pre-defined template, which included personalized air-quality feedback, and information on SHS impacts were given. The feedback was delivered over two 20-minute phone calls or in-person sessions following the completion of the air-quality measurements. Data were corrected for outdoor PM2.5 concentrations from the nearest environmental monitor. RESULTS: Despite the challenges in conducting the project during COVID-19 pandemic, the delivery of the intervention was found to be feasible. Twenty-seven (77%) out of 35 participants completed PM2.5 measurements and received a complete intervention. The median (IQR: 25th -75th percentile concentrations) SHS-PM2.5 concentrations at baseline and follow-up were 18.3 µg/m3 (IQR: 13.3-28.3) and 16.2 µg/m3 (IQR: 10.4 - 25.6), respectively. There was a reduction of SHS-PM2.5 concentrations at follow-up measurement in the houses of 17 participants (63%). The change in corrected indoor PM2.5 concentrations between baseline and follow-up was not statistically significant (Z= -1.01, p=0.29). CONCLUSIONS: This educational intervention, combining the use of a low-cost air particle counter with personalized air-quality feedback, was found to be feasible in the Malaysian setting. It has potential to trigger behavior change among smokers, reducing indoor smoking and consequent SHS concentrations, and increasing smoke-free home implementation. A large-scale trial is needed.

Smoke-free spaces: a decade of progress, a need for more?

Adoption of smoke-free measures has been one of the central elements of tobacco control activity over the past 30 years. The past decade has seen an increasing number of countries and proportion of the global population covered by smoke-free policies to some extent. Despite reductions in global smoking prevalence, population growth means that the number of non-smokers exposed to the harms caused by secondhand smoke remains high. Smoke-free policy measures have been shown to be useful in protecting non-smokers from secondhand smoke, and can additionally increase cessation and reduce smoking initiation. Policies tend to be aimed primarily at enclosed public or workplace settings with very few countries attempting to control exposure in private or semiprivate spaces such as homes and cars, and, as a result, children may be benefiting less from smoke-free measures than adults. Compliance with legislation also varies by country and there is a need for education and empowerment together with guidance and changing social norms to help deliver the full benefits that smoke-free spaces can bring. Restrictions and policies on use of electronic cigarettes (e-cigarettes) in smoke-free settings require more research to determine the benefits and implications of bystanders' exposure to secondhand e-cigarette aerosol, dual use and smoking cessation.

Electronic cigarettes and indoor air quality: a review of studies using human volunteers.

OBJECTIVE: This paper is primarily aimed to review articles on electronic cigarettes (e-cigarettes) focusing on indoor air quality (IAQ) assessment that were conducted using human volunteers under natural settings that mimic actual vaping scenarios. Such studies may give a better representation of the actual potential exposure towards e-cigarettes emissions in indoor settings. METHODS: A systematic literature search was conducted using PubMed search engine database. Search terms such as "electronic cigarette", "e-cigarette", "electronic nicotine delivery system", and "indoor air quality" were used to identify the relevant articles to be included in this review. Articles that involved human volunteers who were asked to vape in natural settings or settings that mimic the actual vaping scenario were chosen to be reviewed. The search yielded a total of 15 published articles. Eleven articles were excluded due to 1) unavailability of its full-text (n=1), 2) did not involve human volunteers (n=5) and 3) did not involve an IAQ study (n=5). Four articles were critically reviewed in this paper. RESULTS: From the four selected articles, two of the papers focused on the determination of nicotine level released by e-cigarettes whereas the other two covered IAQ parameters namely; particulate matters (PM), propylene glycols, formaldehyde, metals and polycyclic aromatic hydrocarbons (PAHs). Only two of the studies involved determination of biomarkers of exposure. The level of chemical contents released varied between studies. The differences in the brands of e-cigarette used, number of vapers recruited and the sensitivity of the methodologies employed in these studies may be the possible causes for such differences. However, studies using human volunteers conducted in a natural setting are more relevant to portray the actual exposure to vapors among e-cigarettes users and non-users compared to studies using a smoking machine/an exposure chamber. This is because such studies take into account the behavior of consumers and individual retention of nicotine. Such method will therefore avoid the possibility of overestimation in terms of exposures toward e-cigarettes users and non-users. CONCLUSION: There are limited e-cigarette studies on the impact of IAQ performed using human volunteers in natural settings. The available studies however, provided inconsistent scientific evidence on the actual exposure towards the vapor contents as unstandardized methodology were used in conducting such research. Therefore, there is a need to conduct IAQ studies in natural settings by using a standardized protocol in terms of the number of vapers recruited, the size of the indoor settings, the methods used in detecting and quantifying the contents and levels of emissions and the sensitivity of the equipment used in analyzing the contents. This will help in better utilization of the findings from such studies for the use of risk assessment of the exposures towards e-cigarette emissions. There is also a need to emphasize that it is the onus of the manufacturers in providing and proving scientifically sound safety claims for their products prior to commercializing it in the market.