Residual Detections of Erythromycin and Tylosin at Surface Water and Soils in Korea

PP-29-158 Background/Aims: The occurrence of 4 pharmaceuticals (erythromycin and tylosin) in Korean surface waters and soils were investigated. Four big rivers were selected, although over 90% of drinking water is produced from surface waters in this area that has a population of approximately 40 million inhabitants. Methods: Samples were collected from upstream/downstream and near soils, along the Han, Geum, Youngsan, and Nakdong (South Korea) rivers twice a year and analyzed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI). Results: Two target compounds were detected in surface waters but not in benthos soil samples. Erythromycin was detected 61.3% of samples and the concentrations were nd ∼0.028 ng/mL. Tylosin was detected 11.3% of samples and the concentrations were nd ∼0.061 ng/mL. Detection rates and concentrations were different from the rivers. Analytical accuracy and precision (pooled CV) at surface water were as follows: erythromycin was 74.0%, 1.7% and tylosin was 95.7%, 1.5%. Analytical accuracy and precision at benthos soils were as follows: erythromycin was 71.6%, 1.2% and tylosin was 102.5%, 3.5%. Conclusion: This level were similar or more lower than other countries.