Occurrence, fate, and risk assessment of antibiotics in typical pharmaceutical manufactories and receiving surface waters from different regions

This study aimed to update information on the presence and persistence of antibiotics in wastewater from four typical pharmaceutical plants in China and the removal of antibiotics by the wastewater treatment process. It also evaluated the environmental impact of antibiotic residues through wastewater discharge into receiving water bodies. The results indicated that 13 antibiotics were detected in wastewater samples with concentrations ranging from 57.03 to 726.79 ng/L. Fluoroquinolones (FQs) and macrolides (MLs) were the most abundant antibiotic classes in wastewater samples, accounting for 42.5% and 38.7% of total antibiotic concentrations, respectively, followed by sulfonamides (SAs) (16.4%) and tetracyclines (TCs) (2.4%). Erythromycin-H2O (ERY), lincomycin (LIN), ofloxacin (OFL), and trimethoprim (TMP) were the most frequently detected antibiotics; among these antibiotics, the concentration of OFL was the highest in most wastewater samples. No significant difference was found in the removal of antibiotics between different treatment processes, and more than 50% of antibiotics were not completely removed with a removal efficiency of less than 70%. The concentration of detected antibiotics in the receiving water was an order of magnitude lower than that in the wastewater due to dilution. Finally, an environmental risk analysis showed that lincomycin and ofloxacin could pose a high risk at the concentrations detected in effluents and a medium risk in their receiving waters, highlighting that they were a potential hazard to the health of the aquatic ecosystem.