Author(s)

Iguniwari Thomas Ekeu-wei^1*, Kate Ihuaku Azuma², Florence Buloere Biu Ogunmuyiwa³

¹Lancaster Environment Centre, Lancaster University, City of Lancaster, UK.
²Department Animal and Environmental Biology, University of Benin, Benin, Nigeria.
³Department of Mechanical Engineering, Ogwashi-Uku Polytechnic, Ogwashi Ukwu, Nigeria.

With the increasing trend of development and industrialization in Malaysia, air pollution has become an inevitable part of the process, resulting from increased vehicular activities and industrial processes. Toll operators are potentially exposed to high levels of air pollutants from working in proximity to traffic pollution sources, thereby increasing their risk of health defects associated with air pollution exposure. This study assessed the levels of Nitrogen dioxide (NO₂) toll operators are exposed to, considering the influences traffic density and meteorological factors. This is intended to serve as an indicator of the cumulative pollution emanating from the combustion process of vehicles at toll plazas. Using Passive diffusion samplers saturated with Triethanolamine (TEA), the weekly indoor and outdoor NO₂ concentrations at tollbooth were measured at Sungai Besi (SB), Kajang (KJ) and Putra-Makhota (PM) toll Plazas, to capture the varying traffic densities of 138,000, 65,000 and 24,100 vehicles/day respectively. The results showed that NO₂ concentrations increase with traffic densities, and indoor NO₂ concentrations correlated highly with outdoor NO₂ concentrations (R²: SB = 0.767, KJ = 0.689 and PM = 0.877). The indoor/outdoor NO₂ ratio varied from 0.7 to 1.2 for all toll booths, suggesting pollution control in-efficiency, caused by technical and behavioural factors. Also, meteorological factors had no significant effect on nitrogen dioxide concentrations, contrary to previous studies, which is likely due to the far distance between tool plazas and meteorological stations. Furthermore, the NO₂ concentrations reported in this study were higher in comparison to weekly standards adopted in Germany (0.032 ppm) and previous literature. Therefore, toll operators are potentially exposed to high levels of pollution, and we advise that toll operators to wear pollution protection gears to reduce the risk of exposure, and the ventilation systems and mitigation measure (air curtain) reviewed to assess its efficiency.

Nitrogen Dioxide, Passive Diffusion Samplers, Toll Plaza, Traffic, Malaysia, Pollution

Ekeu-wei, I. , Azuma, K. and Ogunmuyiwa, F. (2018) Passive Sampling of Ambient Nitrogen Dioxide at Toll Plazas in Malaysia. Open Journal of Air Pollution, 7, 14-33. doi: 10.4236/ojap.2018.71002.