Effects of architecture structure on volatile organic compound and polycyclic aromatic hydrocarbon diffusion in Singapore's Integrated Transport Hubs.

Abstract Millions of passengers wait for buses at Integrated Transport Hubs (ITH) daily in metropolitan cities. Environmental exposure and associated risk for passengers is of great public concern. In this study, eight volatile organic compounds (VOCs) and the 16 EPA priority polycyclic aromatic hydrocarbons (PAHs) were analyzed in airborne samples collected from indoor waiting areas (Indoor) and bus parks of nine Singapore ITH, which comprises of two types of architectural structure (i.e., fully sheltered and open/partially enclosed). The median concentrations of total VOCs (TVOCs), total gaseous PAHs (TgPAHs) and total airborne particles-adsorbed PAH (TpPAHs) concentrations in Indoor were 30.42 μg/m3, 18.99 ng/m3 and 1.38 ng/m3; respectively. A strong correlation (r ≥ 0.75, p