A cross-sectional study of knowledge about secondhand smoke-attributed diseases, awareness, and applicability of the smoking control law in a southern province of Thailand.

Introduction: Secondhand smoke (SHS) exposure is a significant cause of illness. This study aimed to explore the awareness of SHS-attributed illnesses and the legal control of the Tobacco Product Control (TPC) Act 2017 among the local people living in Meung district, a municipality of Songkhla Province, Thailand.

Methods: This quantitative and qualitative study was conducted in 3 marketplaces and 6 public bus terminals in a southern province of Thailand between November 2021 and September 2022. A total of 330 volunteers were enrolled for the quantitative analysis. Meanwhile, 13 local government officers (LGOs), 2 market visitors, and 5 public vehicle passengers were interviewed for qualitative analysis to evaluate applicability of the law in this province. We collected the participants' general demographics, prevalence of secondhand smoke (SHS) exposure, knowledge about SHS-attributed diseases, and awareness of the law. Chi-squared test was used to assess the associations between demographics and knowledge of SHS-attributed diseases and awareness of the legal restrictions regarding SHS exposure (p<0.05). Thematic analysis for evaluating applicability of the law was conducted from the interviews.

Results: Tobacco smell was experienced more frequently than witnessing smokers in marketplaces (49.8% vs 30.0%) and on public vehicles (45.5% vs 20.7%). The mean ± SD scores of knowledge regarding the law were low (marketplace, 4.09 ± 1.61; bus, 4.07 ± 1.69), while that of SHS-attributed health harms were moderate (marketplace, 6.31 ± 2.14; bus, 6.30 ± 1.64). Age, education level, and religion had significant associations with knowledge about SHS-attributed diseases (p=0.001, <0.001, <0.001, respectively), while age and education level were significantly associated with awareness of the law (p<0.001). We found weaknesses in the collaboration of LGOs. Inadequate resources and a high volume of routine workload were the attributed barriers.

Conclusions: Enhancing knowledge about SHS-attributed illnesses, awareness of the SHS control law, and strengthening public engagement are crucial for SHS exposure control. The collaboration between the local people and LGOs for effective SHS control is advocated.