太湖表层水体典型抗生素时空分布和生态风险评价

采用固相萃取-高效液相色谱串联质谱法对太湖表层水体4类抗生素（磺胺类、喹诺酮类、四环素类和大环内酯类）进行为期1 a的逐月监测，并评估其潜在生态风险.全年18种抗生素在太湖水体中均有不同程度检出，磺胺甲唑、磺胺噻唑、磺胺甲嘧啶、磺胺间甲氧嘧啶和甲氧苄氨嘧啶等5种磺胺类抗生素的检出率均高于50%；喹诺酮类抗生素检出浓度较高，其中，环丙沙星的平均浓度和中位浓度分别为13.0 ng·L^-1和13.5 ng·L^-1.太湖抗生素污染具有明显的月际差异，月平均浓度范围7.3~33.5 ng·L^-1，6~10月抗生素浓度水平较低，2~5月和11月检出浓度较高.太湖水体抗生素在20个监测点位的空间差异小，平均浓度范围13.0~41.3 ng·L^-1.全年太湖抗生素对藻类的中高风险比例达57.5%，其中4月和11月的生态风险较严重，喹诺酮类抗生素可能是主要风险因子，应引起管理部门足够重视.

Spatiotemporal Distributions and Ecological Risk Assessments of Typical Antibiotics in Surface Water of Taihu Lake

Using solid phase extraction-high performance liquid chromatography tandem mass spectrometry, antibiotics belonging to four classes (i.e. sulfonamides, quinolones, tetracycline, and macrolides) in the surface water of Taihu Lake were monitored monthly for a year. Moreover, the potential ecological risks of antibiotics in Taihu Lake were assessed. During the one-year monitoring, all the eighteen target antibiotics were detected to some extent in the surface water. The detection rates of five sulfonamides (sulfamethoxazole, sulfathiazole, sulfadiazine, sulfadimethazine, and trimethoprim) were higher than 50%. The concentrations of quinolones in the surface water were relatively higher. The average and medium concentrations of ciprofloxacin were 13.0 ng·L^-1 and 13.5 ng·L^-1, respectively. There were significant differences in the antibiotic pollution during the different months, with the average concentrations of the target antibiotics ranging from 7.3 to 33.5 ng·L^-1. The concentration levels were lower from June to October, while higher concentrations were observed from February to May and in November. In the surface water of Taihu Lake, the spatial variations of antibiotics among the 20 sampling sites were not significant, with the average concentrations ranging from 13.0 to 14.3 ng·L^-1. During the one-year monitoring, the rates of medium and high risks that the antibiotics posed to algae reached 57.5%. The ecological risks of antibiotics were more severe in April and November, and the quinolones may be the dominant risk factor. This issue should be carefully considered by management authorities.