[Pollution Level, Distribution Characteristics and Risk Assessment of 32 PPCPs in Surface Water of Luomahu Lake]

A total of 22 water samples collected from Luomahu Lake were determined using high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) to evaluate the pollution level,spatial distribution and ecological risk of 32 PPCPs.23 PPCPs were detected in surface water of Luomahu Lake and the total concentrations of 22 samples were 892-1536 ng·L^-1.The concentration of norfloxacin (256-707 ng·L^-1) was the highest among the detected PPCPs,followed by ketoprofen (85-438 ng·L^-1),acesulfame (101-290 ng·L^-1) and naproxen (1.9-112 ng·L^-1).Spatial differences were found in concentrations of PPCPs in various sampling sites.Concentrations of PPCPs in northeast of Luomahu Lake were higher than those of southwest.Concentration of PPCPs in Fangtinghe River was high and that of Zhangshanzha River was relatively low.The risk assessment of 13 pharmaceutical PPCPs showed that risk quotients (RQs) of norfloxacin were 0.26-0.72,posing medial risk to aquatic ecosystem.Gemifibrozil posed low ecological risks with RQs>0.01 in most sampling sites.RQs of other 11 PPCPs were less than 0.01,posing no ecological risks.The combined risk quotients of 12 PPCPs in water of Luomahu Lake were 0.29-0.75,indicating that those compounds posed an medial risk to aquatic ecosystem.Human health risk assessment showed that the RQs were less than one for 6 selected PPCPs,indicating that these compounds did not appear to pose an appreciable risk to human health by potential environmental exposure from drinking water.