Indoor Secondary Pollutants Cannot Be Ignored: Third-Hand Smoke

Determining the prevalence of people's knowledge that third-hand smoke is harmful to health: A meta-analysis study

INTRODUCTION

Although the health effects of first-hand smoke and second-hand smoke are well known, third-hand smoke (THS) is a relatively new concept. We estimated the prevalence of people's knowledge that THS is harmful to health, including for some subgroups, in a meta-analysis.

METHODS

We searched PubMed, Web of Science, Scopus, EBSCO Host, ProQuest, and YOKTEZ databases for the prevalence of people's knowledge that THS is harmful to health using specified search words. A total of 12 publications (n = 8549 people) were included in the meta-analysis. The random effect model was used for meta-analysis, and Cochran's Q test and I2 values were used to determine heterogeneity. Subgroup analyzes and meta-regression were also performed.

RESULTS

The prevalence of people's knowledge that THS is harmful was 80.1%. The prevalence of people's knowledge that THS is harmful for children was 82%, and the prevalence of people's knowledge that THS is harmful for adults was 70.4%. For health professionals, the prevalence of people's knowledge that THS is harmful for children was 89.8%, the highest prevalence value calculated in this meta-analysis. Cochran's Q test and I2 values indicated that the included studies were heterogeneous.

CONCLUSIONS

In this meta-analysis, the overall prevalence of people's knowledge that THS is harmful was 80.1%, but large variations were found between samples.

The association between anti-smoking legislation and prevalence of acute respiratory illnesses in Indian children

Objective

Exposure to tobacco smoke causes numerous health problems in children, and create burden on the population in terms of economy, morbidity and mortality. In order to protect the child from exposure to tobacco smoke in the outdoor environment, sufficient legislative enactments are available in Indian legislation. The objective of the present study is to investigate the fact that in absence of any specific laws stating about protection of children from exposure to tobacco smoke in indoor environment, whether outdoor related legislations are sufficient to protect children from exposureand to explore the scope for enforcement of both state and central laws in improving health of children in India.

Study design

The study considered cross-sectional survey data of Demographic and Health Survey Data on India, National Family and Health Survey fourth round (NFHS-4) for the year 2015-16 on Indian children (below age of four).

Methods

Both bivariate and multivariate logistic regression models were used to assess the impact of anti-smoking laws on the prevalence of acute respiratory infection (ARI) based on the place of residence, indoor tobacco smoke exposure and age of the child.

Results

The results have shown an inclination of ARI among children in association with states having single law, rural area resident, exposure to indoor tobacco smoke and age of the child, both as independent or in combination are quite conspicuous, and are found to be underestimated. The logistic regression also revealed the influence of these factors both as independent and even in interaction with other.

Conclusions

Legislative intervention through both at central (or national)and state levels through anti-smoking laws will decrease the indoor tobacco smoke exposure as a result ARI prevalence will also decrease among children in India.

Control of tobacco-specific nitrosamines by the Bacillus siamensis: Strain isolation, genome sequencing, mechanism analysis and genetic engineering

Nitrosamines are considered carcinogens that threaten human health and environment. Especially, high contents of Tobacco-specific nitrosamines (TSNAs) are generated during the fermentation process of cigar tobacco. To control the accumulation of TSNAs, one novel strain WD-32 was isolated by comprehensively evaluating the reduction characteristics of nitrate, nitrite, and TSNAs, and this strain was identified as Bacillus siamensis by 16 S rRNA gene analysis and MALDI-TOF MS evaluation. Subsequently, whole genome sequencing of B. siamensis WD-32 was carried out to excavate important genes and enzymes involved, and the possible reduction mechanism of TSNAs was explored. More importantly, the reduction of TSNAs by B. siamensis was significantly promoted by knockout of narG gene. During the practical agricultural fermentation process of the cigar tobacco leaves, the treatment by the WD-32∆narG cells resulted in a 60% reduction of the total TSNAs content compared with the control, and the concentrations of the NNN and NNK were decreased by 69% and 59%, respectively. In summary, this study offers efficient strains for reduction of the TSNAs in cigar tobacco, and provides new insights into the reduction mechanism of TSNAs, which will promote the application of microbial methods in control of TSNAs and nitrite.

Thirdhand smoke beliefs, exposure status and associated factors among young people in China: A cross-sectional study

INTRODUCTION

Thirdhand smoke is an emerging threat to global public health. There is no research on young people's exposure to thirdhand smoke in China. This study aims to investigate the exposure status and beliefs of thirdhand smoke among young Chinese people and provide a reference for policy regarding thirdhand smoke.

METHODS

Data from the 2022 Chinese Resident Psychological and Behavioral Survey were used to select young people aged 15-24 years. A total of 11781 subjects were included in this study. Demographic information, beliefs about thirdhand smoke, and exposure status to thirdhand smoke were investigated.

RESULTS

Among the participants, 47.8% reported being exposed to thirdhand smoke (males: 49.1%, females: 47.0%). Young people living in urban areas (AOR=0.84, 95% CI: 0.77-0.91, p<0.001) and those with a monthly family income >12000 RMB (AOR=0.81, 95% CI: 0.71-0.92, p=0.001) were less likely to be exposed to thirdhand smoke. Young people with junior high school education or higher, and current or former smokers, were more likely to be exposed to thirdhand smoke. There is room for improvement in the beliefs about thirdhand smoke among young people.

CONCLUSIONS

Thirdhand smoke exposure is an issue that should be addressed in public health policy. Young people with low income and current or former smokers are populations that should be mainly focused on in public education and prevention work on thirdhand smoke.

Thirdhand Smoke May Promote Lung Adenocarcinoma Development through HN1

Thirdhand smoke (THS) refers to residual tobacco smoking pollutants that can be adsorbed to indoor surfaces and dust and persist for years after active smoking. THS-related chemicals such as N-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) are tobacco-specific lung carcinogens that involved in lung cancer development and progression. In this study, we computed the differentially expressed genes (DEGs) between THS and paired control samples. THS-related overexpressed genes (OEs) were overlapped with OEs of lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). Survival analyses of these overlapped genes were performed using LUAD and LUSC data. 6 genes were selected for validation based on their expression levels and prognostic value. Hematological and neurological expressed 1 (HN1) was further selected due to its novelty in LUAD research. The potential roles of HN1 in LUAD were explored in several ways. In summary, HN1 is overexpressed in THS samples and is associated with the prognosis of patients with LUAD. It may promote cancer progression through several pathways and could serve as a potential therapeutic target especially for THS-related LUAD. In-depth mechanistic studies and clinical trials are warranted.

Indoor Exposure and Regional Inhaled Deposited Dose Rate during Smoking and Incense Stick Burning-The Jordanian Case as an Example for Eastern Mediterranean Conditions

Tobacco smoking and incense burning are commonly used in Jordanian microenvironments. While smoking in Jordan is prohibited inside closed spaces, incense burning remains uncontrolled. In this study, particle size distributions (diameter 0.01-25 µm) were measured and inhaled deposited dose rates were calculated during typical smoking and incense stick-burning scenarios inside a closed room, and the exposure was summarized in terms of number and mass concentrations of submicron (PN_Sub) and fine particles (PM_2.5). During cigarette smoking and incense stick-burning scenarios, the particle number concentrations exceeded 3 × 10⁵ cm^-3. They exceeded 5 × 10⁵ cm^-3 during shisha smoking. The emission rates were 1.9 × 10¹⁰, 6.8 × 10¹⁰, and 1.7 × 10¹⁰ particles/s, respectively, for incense, cigarettes, and shisha. That corresponded to about 7, 80, and 120 µg/s, respectively. Males received higher dose rates than females, with about 75% and 55% in the pulmonary/alveolar during walking and standing, respectively. The total dose rates were in the order of 10¹²-10¹³ #/h (10³-10⁴ µg/h), respectively, for PN_Sub and PM_2.5. The above reported concentrations, emissions rates, and dose rates are considered seriously high, recalling the fact that aerosols emitted during such scenarios consist of a vast range of toxicant compounds.