Spatial variations, source apportionment and potential ecological risks of polycyclic aromatic hydrocarbons and synthetic musks in river sediments in Shanghai, China.

The aims of this study were to investigate the levels, possible sources and potential ecological risks of 26 polycyclic aromatic hydrocarbons (PAHs) including highly carcinogenic dibenzopyrene (DBP) isomers and 4 synthetic musks (SMs) in river sediments from Shanghai. 74 sediment samples were collected from the Huangpu River and its main tributaries. The total concentrations ranged from 52.0 to 11400 ng g-1 for Σ26 PAHs, 25.1-9910 ng g-1 for 16 USEPA priority PAHs (Σ16 PAHs), 0.769-384 ng g-1 for Σ4 DBPs, and 0.080-63.3 ng g-1 for Σ4 SMs, respectively. Seven sources of PAHs in river sediments were identified by positive matrix factorization (PMF) model. Coal combustion, vehicle and creosote were the major emission sources for PAHs. SMs came mainly from domestic and industrial wastewaters. The toxic equivalent quantities of the benzo[a]pyrene (TEQBaP ) ranged from 7.64 to 3920 ng g-1 for Σ24 PAHs, 2.07-1150 ng g-1 for Σ16 PAHs, and 5.53-3150 ng g-1 for Σ4 DBPs. The TEQBaP of Σ4 DBPs made up 73.9% of Σ24 PAHs, which indicated that DBPs were the major carcinogenic contributors to total PAHs in sediments. According to sediment quality guidelines (SQGs) and mean PEL-Q values, the risks posed by PAHs in sediments were at medium level at most sampling sites, and SMs posed a low ecological risk to sediment-dwelling organisms in Shanghai.