渭河西安段磺胺类抗生素的分布特征及生态风险评价

Occurrence and ecological risk of sulfonamide antibiotics in the surface water of the Weihe Xi'an section

采用HPLC-MS/MS对渭河西安段(咸阳至西安)表层水体中的磺胺类抗生素污染物进行检测分析,丰水期共检出包括磺胺嘧啶、磺胺二甲嘧啶、磺胺甲唑、磺胺间甲氧嘧啶、磺胺吡啶、磺胺喹喔啉、磺胺氯哒嗪和磺胺增效剂甲氧苄啶8种药物残留,检出率50%—100%,检出浓度nd—178.44 ng·L^(-1);平水期检测到除磺胺氯哒嗪外7种,检出率25%—100%,检出浓度nd—114.46 ng·L^(-1).与国内其他河流相比,渭河西安段检出的磺胺类抗生素种类较多,浓度处于中等水平.磺胺类抗生素的浓度分布呈现:平水期,上游>中游>下游;丰水期,中游>下游>上游的特点;平水期和丰水期共同检出的磺胺类抗生素比较,平水期检出总浓度高于丰水期.源分析初步表明,生活污水、工业和医疗废水、禽畜和水产养殖是渭河西安段磺胺类抗生素浓度水平较高的主要原因.此外,渭河西安段表层水体中磺胺类抗生素浓度与COD、NH_3-N、TN、TP等其他同步水污染指标无明显相关关系.风险商值RQs分析表明除磺胺甲唑(RQs≥1)对相应物种存在高风险,其他抗生素的风险较低(RQs<0.1).

Sulfonamide residues in the surface water of Weihe River（Xianyang to Xi＇ an section）were analyzed by HPLC/MS/MS.Eight sulfonamides,including sulfadiazine（SDZ）,sulfamethazine（SMZ）,sulfamethoxazole（SMX）,sulfamethoxazole（SMM）,sulfadiazine（SPD）,sulfaquinoxaline（SQX）,sulfachloropyridazine（SCP） and a synergist of sulfonamide trimethoxy（TMP） were detected in the wet water period,with the detection rates of 50%—100%,and detected concentrations of nd to 178.44 ng·L^（-1）.In contrast,six sulfonamides and TMP were found in the flat water period,with the detection rate of 25%—100%,the detected concentration of nd—114.46 ng·L^（-1）.Compared with other rivers in China,more types of sulfonamide antibiotics were detected in Weihe River,and the concentrations were in a moderate level.The distribution patternshowed that,in flat water period,sulfonamide concentrations in the upstream were higher than thos in the midstream and downstream,and the lowest in wet water period.The source apportionment revealed that domestic sewage,industrial and medical waste water,poultry and aquaculture contributed to the higher level of sulfonamides.Moreover,the total concentration of the same detected sulfonamides in flat water period was higher than that in wet water period.There was no significant correlation between sulfonamides concentration and the simultaneous water pollution indexes,such as COD,NH_3-N,TN,and TP.And the risk quotient（RQs） indicated that SMX posed higher risk to the corresponding species,with RQs greater than 1.