SOURCE CHARACTERIZATION AND HUMAN HEALTH RISK ASSESSMENT OF ALIPHATIC AND POLYCYCLIC AROMATIC HYDROCARBONS FROM URBAN ROAD DUSTS IN A CHINESE HEAVILY POLLUTED CITY

The investigation was carried out on source characterization and human health risks associated with n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in road dusts from different functional areas in Taiyuan as the Chinese coal capital. The average concentrations of n-alkanes and PAHs ranged from 128.53 to 190.78 mu g/g and from 10.99 to 28.10 mu g/g, respectively. N-alkane indexes and diagnostic ratios of PAHs were calculated to identify sources of hydrocarbons. The results showed that n-alkanes mainly derived from petroleum residues with a moderate input of territorial higher plant waxes. PAHs of pyrogenic mainly came from coal and diesel combustion. Risk analyses indicated that 95% Upper Control Limit of Incremental Lifetime Cancer Risk (ILCR) for children and adults exposed to dust-borne PAHs was up to 4.37x10(-6) and 5.51x10(-6), respectively, which displayed potential cancer risks.