Occurrence of Antibiotics in Water, Soil, and Sediment Neat at the Confined Animal Feeding Operations (CAFOs) in Korea.

Recently, the worldwide use of antibiotics as active pharmaceutical ingredients (APIs) has caused environmental problems through the occurrence of antibiotic resistant bacteria from their residuals in the environment. However, there is only a limited amount of information available on the occurrence of antibiotics in environmental compartments in Korea. The objective of this research was to monitor the concentrations of antibiotics in water, sediment, and soil ecosystems as they remain critical for human and environmental safety. A sampling plan was proposed to investigate the levels of antibiotics released into individual environmental compartments from a composting facility including the effects of dilution. As far as we are aware, this study is the first report on monitored pharmaceutical residuals in Korean soil as part of a larger project to investigate the fate of these compounds in various environments. Antibiotic concentrations were determined with high performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS) following pretreatment using solid-phase extraction (SPE) in the cleanup process. The examined antibiotics were chlortetracycline (CTC), oxytetracycline (OTC), tetracycline (TC), sulfamethazine (SMT), sulfamethoxazole (SMX), sulfathiazole (STZ) and tylosine (TYL). In water samples, the highest detected levels of CTC, OTC, TC, SMT, SMX, STZ and TYL were 0.76, 1.41, 0.58, 9.12, 0.38, 5.35 and 2.19 µg/L, respectively. The SMT, SMX, STZ and TYL in sediment samples ranged from 38.60–70.32, 8.91-12.20, 23.68-40.31 and 12.32-13.38 µg/Kg, respectively, whilst CTC, OTC and TC were not detected. Generally, lower antibiotic concentrations were measured in the rice paddy soil at the bottom of the water stream with an average of 0.36, 1.68, 20.30, 0.77, 3.32, and 24.39 µg/Kg of CTC, OTC, SMT, SMX, STZ and SAs, respectively. Further research is needed to continuously monitor the fate of antibiotics in various ecosystems and their contribution to environmental risk assessments.

 

 Keywords: veterinary antibiotics, solid-phase extraction, soil, sediment, water