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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 Σ 26 PAHs, 25.1-9910 ng g -1 for 16 USEPA priority PAHs (Σ 16 PAHs), 0.769-384 ng g -1 for Σ 4 DBPs, and 0.080-63.3 ng g -1 for Σ 4 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 (TEQ BaP ) ranged from 7.64 to 3920 ng g -1 for Σ 24 PAHs, 2.07-1150 ng g -1 for Σ 16 PAHs, and 5.53-3150 ng g -1 for Σ 4 DBPs. The TEQ BaP of Σ 4 DBPs made up 73.9% of Σ 24 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., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

As one of China's great metropolises, Taiyuan is generally recognized to be one of the most polluted cities in the world. It is affected by pollution from heavy industries, and from organochlorine pesticides (OCPs). In this study, we measured the concentrations of OCPs in various environmental media in Taiyuan. We measured the levels of OCPs in 15 soil samples and 34 samples of respirable particulate matter (PM) (17 of PM(2.5) and 17 of PM(10)) from urban areas of Taiyuan. Analysis of the composition ratios of OCP residues revealed that dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) were the predominant compounds in soil, PM(2.5) and PM(10). The total DDT concentrations were 1.8-1.0x10(2)ngg(-1) in soil, 6.5-1.0x10(3)pgm(-3) in PM(2.5), and 8.5-1.5x10(3)pgm(-3) in PM(10). The total HCH concentrations were 1.4-45ngg(-1) in soil, 5.2-8.0x10(2)pgm(-3) in PM(2.5), and 9.6-8.7x10(2)pgm(-3) in PM(10). Furthermore, source analysis indicated that there was new input of OCPs at some sites. Finally, analysis of the individual OCPs revealed that new OCP contamination was the major problem in Taiyuan. This study suggests that measures should be taken to reduce the levels of OCP residues in order to improve the environmental quality in Taiyuan.

As one of China's great metropolises, Taiyuan is affected by heavy chemical industry and manufacture of chemical products, and faces pollution from polychlorinated biphenyls (PCBs). Therefore, this study was conducted to determine the PCB concentrations in various environmental media in Taiyuan. We collected 15 soil samples, 34 respirable particulate matter (PM) samples (17 of PM(2.5) and 17 of PM(10)) from urban areas of Taiyuan, and measured a total of 144 PCB congeners (including some coeluting PCB congeners). The total PCB concentrations were 51-4.7 x 10(3) pg g(-1) in soil, 27-1.4 x 10(2) pg m(-3) in PM(2.5) and 16-1.9 x 10(2) pg m(-3) in PM(10). Of the PCB homologues, the dominant PCBs detected in the various media were all tri-CBs. Soil was relatively the most polluted media. Furthermore, principal-component analysis revealed that the major PCB source in Taiyuan may be associated with the main commercial PCB through long-range transmission. Toxic equivalency (TEQ) concentrations (based on ten dioxin-like PCBs) ranged from N.D. to 5.9 x 10(-3) pg-WHO TEQ g(-1) in soil, 2.0 x 10(-4)-3.4 x 10(-3)pg-WHO TEQ m(-3) and 1.0 x 10(-4)-1.2 x 10(-3) pg-WHO TEQ m(-3) in PM(2.5) and PM(10), respectively. In previous studies, PCBs were not a severe component of contaminant in Taiyuan; however, this study suggested there is a potential threat of human exposure to PCBs for residents of Taiyuan.