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Forty two surface water samples were collected in May and June of 2013 in five lakelets of the East Lake, China. Four steroid hormones (17β-estradiol (βE2), estrone (E1), 17α-estradiol (αE2) and 17α-ethinylestradiol (αEE2)) were analyzed in these samples. Determination of four estrogenic compounds was performed on high performance liquid chromatography/mass spectrometry (HPLC/MS). βE2 was detected with the highest detection frequency of 62% and its concentration range was from nd to 17.58 ng/L. The mean total concentration of four compounds increased with the order: Houhu lake (L5) (8.91 ng/L) < Niuchao lake (L1) (19.92 ng/L) < Guozheng lake (L2) (20.03 ng/L) < Tangling lake (L4) (22.65 ng/L) < Guandu lake (L3) (35.68 ng/L). Pollution sources of four compounds were mainly from municipal wastewater and water washed out from farm land fertilized with the waste of livestock or irrigated with water from livestock farm. The proportion of sample sites at high risk that compounds had effect on fish population were 58.3% in Guozheng (L2) lake, 100% in Guandu (L3) lake, and 62.5% in Tangling (L4), Niuchao (L1) and Houhu (L5) lake, respectively. The mean βE2 equivalent concentrations was at relatively high levels in L3 with 8.6 ng/L, L1 with 6.1 ng/L, L4 with 4.62 ng/L, L2 with 4.58 ng/L and L5 with 2.62 ng/L, respectively. Meanwhile, sampling sites at high risk generally were surrounded with hospitals, hotels and residential buildings where had high population density. [ABSTRACT FROM AUTHOR]

Fifteen polycyclic aromatic hydrocarbons (PAHs) and heavy metals (Cr, Ni, As, Cd, Pb, and Hg) were quantified in 19 surface water sites of the Three Gorges Reservoir, China. The total concentrations of 15 PAHs and six heavy metals in the 19 sample sites ranged from 130.8 ng L−1to 227.5 ng L−1and 3.2 μg L−1to 6.0 μg L−1, respectively. The mean concentration of As was the highest among the six heavy metals (2.1 ± 0.3 μg L−1), followed by Cr (0.5 ± 0.3 μg L−1), Ni (1.3 ± 0.1 μg L−1), Cd (0.2 ± 0.01 μg L−1), Pb (0.07 ± 0.08 μ g L−1) and Hg (0.05 ± 0.08 μg L−1). The isomer ratio results suggest that PAHs at most sites were mainly from petroleum combustion, while coal and biomass combustion was the main source at sites 1, 2, 6, 7, 9, 14, and 17. Based on principal component analysis, the main source of heavy metals was anthropogenic activities and weathering of bedrocks. Depending on characteristic of RQ(NCs)≥ 1 and RQ(MPCs)< 1, BaA showed higher potential ecological risk than other PAHs, therefore, all sampling site needed to be paid much more attention, included some remedial actions. Meanwhile, after assessing human health risk of heavy metal, it was unlikely to experience adverse health effects, even exposing through more pathways and six kinds of heavy metals simultaneously. [ABSTRACT FROM PUBLISHER]