Occurrence and behavior of antibiotics in water and sediments from the Huangpu River, Shanghai, China

This study aims to determine the occurrence and behavior of five classes of 20 antibiotics in both water and sedimentary phases in the Huangpu River, which supplies drinking water to Shanghai City, China. Of the 20 antibiotics, sulfonamides showed the highest concentrations in water samples (34-859ngL^-1) while tetracyclines (average concentration at 18μgkg^-1 dry weight) and macrolides (12μgkg^-1 dry weight) dominated in sediment samples. The spatial distribution of antibiotics showed that the main polluting sources into the river were animal farming sites and the tributaries downstream of the Yuanxie River. In addition, linear relationships between logK_oc and logK_ow, and between logK_oc and log molecular weight, were demonstrated, suggesting the importance of contaminant properties in inter-phase behavior. The environmental risk assessment revealed that some antibiotics, in particular sulfamethoxazole could cause medium damage to daphnid in the aquatic ecosystem.