[Characteristics of chloramphenicol and tetracyclines in municipal sewage and Nanming River of Guiyang City, China].

The characteristics of chloramphenicol and tetracyclines in municipal sewage and Naming River of Guiyang City were studied, using solid-phase extraction with high-performance liquid chromatography-UV detection. The average concentration of chloramphenicol, oxytetracycline, tetracycline and chlortetracycline in municipal sewage is 27.0, 2.3, 11.0 and 1.1 microg x L(-1) at northern outfall, and 21.2, 2.1, 9.5 and 0.5 microg x L(-1) at southern outfall. Nanming River is influenced by many antibiotic sources which include agriculture land, surface waste and municipal sewage, and the municipal sewage is the most important one. The concentration of chloramphenicol, oxytetracycline and tetracycline in river water ranges from 2.1 to 19.0 microg x L(-1), ND to 3.0 microg x L(-1) and 0.8 to 6.8 microg x L(-1) in winter, and 0.2 to 1.3 microg x L(-1), ND to 0.03 microg x L(-1), 0.2 to 0.3 microg x L(-1) in summer. Chlortetracycline was only detected in winter with the concentration range of 0.09 to 0.14 microg x L(-1). The average concentration of the four compounds in sediment is 147.6, 76.6, 99.2 and 1.6 microg x kg(-1) in winter, 195.8, 89.1, 34.4 and 9.0 microg x kg(-1) in summer, respectively. The antibiotics concentration of both river water and sewage shows a seasonal variation.