Characteristics of airborne particles in stone quarrying areas: Human exposure assessment and mitigation.

This investigation aims to assess the levels of human exposure to airborne particulate matter (PM) in various locations of a natural stone quarry for the first time based on simultaneous measurements of both PM mass and number concentrations (PMC and PNC). A quarry located in Danang city, Vietnam, considered to be a "hotspot" of air pollution in the city, was selected for detailed investigations. Both PMC and PNC were found to be significantly higher (1.2-6.0 times) within the quarry compared to surrounding areas. Mechanical activities during mining, notably crushing, screening, hauling, and loading stones, contributed to increased emissions of PM in the coarser mode (1-10 µm) compared to the accumulation mode (0.1-1 µm) and thus increased deposition of PM1-10 in the human upper respiratory tract. In contrast, combustion activities, especially the diesel engine exhaust from various machines and vehicles used in the quarry, resulted in increased emissions of small particles in the accumulation mode that dominated the PNC and in their deposition in the lower respiratory tract. Simultaneous measurements of PNC and PMC revealed that the PM counts were strongly associated with PM deposition in the alveolar region (accounting for ≈ 76% of total PNC of particles less than 10 µm, N10), while the PM mass concentration was a better indicator of the deposition of PM in the head airway region (≈92% of total PMC of PM10). Overall, this study demonstrates the significance of measuring both PNC and PMC to assess PM exposure levels, regional respiratory doses, and potential health effects associated with human exposure to PM generated from stone quarrying activities. The novelty of this work is the integration of real-time mass and number concentrations of PM over the size range from 20 nm to 10 µm to provide insights into respiratory deposited doses of size-fractionated PM among quarry workers.

Health risks and perceptions of residents exposed to multiple sources of air pollutions: A cross-sectional study on landfill and stone mining in Danang city, Vietnam.

Health risks and perceptions of residents living nearby landfills or stone mines/quarries have been well documented; however, the multiple impacts of these two pollution sources have yet to be investigated. This study aims at giving insights into the impacts of residents exposed to two pollution sources in Danang city, Vietnam: Khanh Son landfill and Phuoc Tuong quarry. In this cross-sectional study, 7-point-Likert scale questionnaires were used to collect information from 314 respondents which were divided into three groups: i) Landfill-Stone mine (LS) exposed group within 1 km from both sources, ii) Stone mine (ST) exposed group within 1 km from the stone mine, and iii) the far-exposed group about 2-3 km from the two emission sites. Air pollutants (including H2S, CH4, and total suspended particles (TSP)) and noise levels were also sampled. In addition, we estimated the potential health risk assessment due to the exposure to hydrogen sulphide in the study areas. The findings have shown that 1) There is a statistical difference (p-value < 0.001) between the two exposed groups and far-exposed group regarding health risks and residents' perceptions; 2) Compared to the ST exposed group, the LS exposed group statistically showed a higher perception to bad odours and skin diseases; lower satisfaction with regards to the personal health condition and the operation of the landfill; and higher willingness to change current living locations; and 3) There is evidence to indicate that elevated concentrations of air pollutants are associated with the high self-reported health risks and residents' perceptions. Urgent actions should be focused on the LS exposed group, landfill and quarry operations to prevent further adverse health effects.

Mobile phone use among car drivers and motorcycle riders: The effect of problematic mobile phone use, attitudes, beliefs and perceived risk.

Mobile phone use while driving presents significant risks, potentially leading to injury or death through distracted driving. Using a case study of Vietnam, this research aimed to understand the effect of problematic mobile phone use (also known as mobile phone addiction or compulsive mobile phone use), attitudes and beliefs, and perceived risk on the frequency of mobile phone use among motorcyclists and car drivers. A self-administered questionnaire was distributed to motorcyclists (n1= 529) and car drivers (n2= 328) using an online survey and face-to-face survey. The survey took around 20-min to complete and participants were entered into a lottery for supermarket vouchers. Of the motorcyclists, 42% of the sample (the highest proportion) was in the 18-25 age group while the 36-45 age group accounted for the highest proportion among car drivers (34.8%). Using structural equation modelling (SEM), key findings showed that each construct influenced mobile phone use, but in different ways for motorcycle riders and car drivers. Attitudes and beliefs had the largest effect on mobile phone use while riding among motorcyclists, with problematic mobile phone use having the smallest influence. In contrast, problematic mobile phone use had the largest effect on mobile phone use while driving a car, with attitudes and beliefs having the smallest effect. The findings of this study point to the need for tailored interventions involving a range of actors (policymakers, police enforcement, mental health professionals, advocacy groups and the wider community) to raise awareness, modify attitudes and increase risk perception associated with mobile phone use while driving/riding. This can be achieved thorough educational tools and road safety campaigns which are focused on reducing this risky driving behaviour. This includes customising road safety programs for individuals and groups affected by problematic mobile phone use such as targeted advertising.