Residue levels and spatial distribution of phthalate acid esters in water and sediment from urban lakes of Guangzhou, China

The residue levels and composition profiles of phthalate acid esters (PAEs) in water and sediment samples were investigated in eight urban lakes of Guangzhou, China. A total of 23 water and 16 sediment samples were collected. Results showed that all target PAEs were detected with dimethyl phthalate and di(2-ethylhexyl) phthalate as the most abundant compounds. The total concentrations of PAEs from different urban lakes were in the range of 273-1173 ng/L for water and 16.5-242 ng/g for sediments, with the geometric mean of 515 ng/L and 75.0 ng/g, respectively. Zhongshan Park Lake and Liwan Lake were the most highly contaminated with PAEs in water and in sediment, respectively. The spatial distribution of PAEs exhibited that distribution coefficients of PAEs between sediment and water are consistent with hydrophilicity of PAEs, and pollution levels and characteristics of PAEs in different lakes had a close relationship with the geographical location of the lake, industrial and commercial types, population density, and the association between the lake and the Pearl River. According to Pearson correlation analysis, PAEs would be derived from similar or identical sources. Risk assessment suggested that the exposure of PAEs in Guangzhou has a moderate toxicity at the current level.