Indoor human exposure to size-fractionated aerosols during the 2015 Southeast Asian smoke haze and assessment of exposure mitigation strategies

Abstract

The 2015 smoke haze episode was one of the most severe and prolonged transboundary air pollution events ever seen in Southeast Asia (SEA), affecting the air quality of several countries within the region including Indonesia, Malaysia and Singapore. The 24 h mean outdoor PM 2.5 (particulate matter (PM) with aerodynamic diameter ≤ 2.5 m) concentrations ranged from 72-157 g m −3 in Singapore during this episode, exceeding the WHO 24 h mean PM 2.5 guidelines (25 g m −3 ) several times over. The smoke haze episode not only affected ambient air quality, but also indoor air quality due to the migration of PM of different sizes from the outdoor to the indoor environment. Despite the frequent occurrence of smoke haze episodes over the years, their potential health impacts on indoor building occupants remain largely unknown in SEA due to the lack of systematic investigations and observational data. The current work was carried out in Singapore to assess human exposure to size-resolved PM during the 2015 smoke haze episode, and to evaluate the effectiveness of exposure mitigation measures in smoke-haze-impacted naturally ventilated indoor environments. The potential health risks associated with exposure to PM 2.5 were assessed based on the concentrations of redox active particulate-bound trace elements, which are known to be harmful to human health, with and without exposure mitigation. Overall, it was observed that human health exposure to PM 2.5 and its carcinogenic chemical components was reduced substantially by 62% (p < 0.05) while using an air cleaner. However, extremely small hazardous particles were only partially removed by the air cleaner and remain a matter of concern for public health.

Sick building syndrome and associated risk factors among the population of Gondar town, northwest Ethiopia

“…The prevalence of SBS was higher among occupants who lived in houses with no fan. Other studies also reported similar findings [ 40 , 41 ]. This is because fan-assisted ventilation improves the quality of the indoor air [ 42 , 43 ].…”

Air quality index prediction using IDW geostatistical technique and OLS-based GIS technique in Kuala Lumpur, Malaysia

“…The climate is facing two monsoonal winds, which initiate from the northeast among October and February, and from the southwest between May and September (Cheong et al 2013). Some countries of Southeast Asia has faced a severe event of haze in 2015 (Sharma and Balasubramanian 2019). Figure 1 shows the study area Kuala Lumpur.…”

Commuting in Los Angeles: Cancer and Non-cancer Health Risks of Roadway, Light-Rail and Subway Transit Routes

“…Calculating ELCR using cancer potency values provided by OEHHA and USEPA, along with the CDI value, which incorporates several exposure factors such as body weight and breathing rate, is a more robust method of cancer risk determination. Sharma and Balasubramanian (2017) in their paper examining wildfire smoke haze-related …”