Due to the abuse of antibiotics, a large amount of antibiotics has been entering wastewater treatment plants (WWTPs), but the pollution of antibiotics in township WWTPs has not attracted much attention. To understand the contamination level and removal characteristics, and the risks to aquatic organisms and human health, samples collected from the inlet and outlet of 15 township WWTPs were investigated. The results showed that tetracyclines (TCs) had the highest concentration in the inlet and outlet waters, in which the concentrations of TC and oxytetracycline (OTC) reached (4 943.69±4.31) ng·L-1 and (3 907.81±52.04) ng·L-1. As for antibiotic removal, the A/O and A2/O processes had a better antibiotic removal capacity than those of the MBR process. Ecological risk assessment showed that TCs and fluoroquinolones (FQs) had a higher risk to aquatic organisms. However, sulfonamides (SAs) would pose a low risk to aquatic organisms. Although antibiotics pose a risk to aquatic organisms, the risk to human health is negligible. The results of this study could provide support for the upgrading of township WWTPs and the formulation of regional antibiotic discharge standards in the future.
Keywords: antibiotics; ecological risk assessment; pollution levels; removal efficiency; wastewater treatment plants(WWTPs).