中文摘要：

利用固相萃取／高效液相色谱-质谱分析了天津市某供水管网中5类16种抗生素的时空分布特征，并对抗生素污染的健康风险进行了评估。结果表明，监测期内供水管网中不同时间的抗生素污染状况存在差异，7月份抗生素的检出数量最多、浓度最高，该月管网起点处抗生素的总浓度达到26．6ng／L。随着管网的延伸，抗生素的浓度存在“先减后增”的趋势，管网起点和管网末端是抗生素污染较为集中的部位。健康风险评估表明，目前供水管网中抗生素污染物浓度水平极低，不太可能会对人体产生急性毒性。

英文摘要：

The temporal and spatial characteristics of 16 antibiotics belonging to 5 categories in drinking water distribution networks were analyzed using solid-phase extraction with high-performance liquid chromatography-tandem mass spectrometry. It was shown that the detection of antibiotics varied between months in summer. The detection frequency and the concentration of antibiotics were the highest in July, and the total concentration of antibiotics at the starting point of the network was as high as 26.6 ng/ L. The concentration of antibiotics descended at first and then increased in the drinking water network; therefore, the beginning and the end of the drinking water distribution system ought to be monitored intensely for the antibiotic pollutions. It was evident that antibiotics had polluted the drinking water in the studied network; however, the concentrations were too low to cause any acute toxicity to human.