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 for ΣPAHs, 25.1-9910 ng g for 16 USEPA priority PAHs (ΣPAHs), 0.769-384 ng g for ΣDBPs, and 0.080-63.3 ng g for ΣSMs, 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 (TEQ) ranged from 7.64 to 3920 ng g for ΣPAHs, 2.07-1150 ng g for ΣPAHs, and 5.53-3150 ng g for ΣDBPs. The TEQ of ΣDBPs made up 73.9% of ΣPAHs, 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.