Abstract:
Surveys concerning the occurrence and removal characteristics of 41 target antibiotics from 5 classes of typical emission sources (municipal wastewater treatment plant (WWTP), pharmaceutical factory, hospital, landfill and livestock farm) in downtown Guangzhou were conducted. Antibiotics were identified and quantified using rapid resolution liquid chromatography tandem mass spectrometry (RRLC-MS/MS) combined with solid-phase extraction (SPE) for pretreatment. The results showed that 24, 14, 15, 12 and 13 antibiotics were detected in WWTPs, pharmaceutical factories, hospitals, landfills and livestock farms, respectively, and the highest detected concentration of single antibiotic was 917 ng/L (oxytetracycline in WWTPs), 127 g/L (roxithromycin in pharmaceutical factories), 11.8 g/L (roxithromycin in hospitals), 3.61 g/L (erythromycin-H2O in landfills) and 664 g/L (oxytetracycline in livestock farms), respectively. Antibiotics were well removed in landfills and livestock farms with the total removal rate of 99.7% and 99.5%, and limited removed in WWTPs, pharmaceutical factories and hospitals with the total removal rate of 49.3%, 63.0% and 26.9%, respectively. The mass load and emission per capita of total antibiotics discharged into the environment in aquatic phase was 1.21 kg/d and 89.3 g/d in downtown Guangzhou, respectively. Incomplete removed antibiotics from typical emission sources constitute one of significant sources of antibiotic contamination in the aquatic environment.