大通湖表层水体中抗生素赋存特征与风险

摘要

为了评价大通湖表层水体中典型抗生素的赋存特征及生态风险等级,采用超高效液相色谱-串联质谱仪(UPLC-MS/MS)检测了4类12种(磺胺类,磺胺增效剂,喹诺酮类和四环素)抗生素的浓度水平.结果表明:除氧氟沙星外,其余11种抗生素均有检出,其总浓度为0.19～261.89ng/L;磺胺嘧啶的平均浓度最高(37.41ng/L),其次为磺胺甲恶唑(12.34ng/L)>沙拉沙星(8.55ng/L)>恩诺沙星(8.04ng/L)>甲氧苄啶(7.56ng/L)>金霉素(3.92ng/L),并且磺胺嘧啶、四环素、沙拉沙星、金霉素、磺胺甲恶唑和甲氧苄氨嘧啶的检出率均超出50％,处于较高水平.与部分河流、湖泊相比,大通湖抗生素的浓度除磺胺嘧啶和恩诺沙星外,基本处于较普通水平;在空间分布上表现为明显的差异性.环境和健康风险评价结果表明:磺胺甲恶唑、沙拉沙星和环丙沙星为大通湖主要的风险因子,RQ>1,对洞庭湖有较高的潜在风险;点位S2、S3、S6对大通湖周围环境具有较高的累积风险,主要的贡献因子分别为恩诺沙星和沙拉沙星、磺胺甲恶唑和环丙沙星;11种抗生素通过饮水途径对成人和儿童的健康风险指数RQH处于8.74×10-8～9.17×10-3之间,且通过饮水途径摄入抗生素对儿童的健康风险高于成人.%The concentrations of 12 antibiotics.classified into sulfanilamides (SAs), trimethoprim (TMP), quinolones (QNs) and tetracyclines (TCs) in surface water of the Datong Lake, were detected by UPLC-MS/MS in order to assess the occurrence and risk level of typical antibiotics. 11 antibiotics were detected expect for ofloxacin, and the total concentrations of antibiotics ranged from 0.19ng/L to 261.89ng/L in surface water. The highest average concentration was sulfadiazine (37.41ng/L), followed by sulfamethoxazole (12.34ng/L)>sarafloxacin (8.55ng/L)> enrofloxacin (8.04ng/L)> trimethoprim (7.56ng/L)> chlortetracycline (3.92ng/L). The detection frequencies of sulfa-diazine, tetracycline, chlortetracycline, sarafloxacin, trimethoprim and sulfamethoxazole, were over 50％, could be higher than 50％. The pollution level was similar to those of other rivers and lakes in China expect for sulfadiazine and enrofloxacin. Spatially, the pollution level of antibiotics in Datong Lake showed distinct differences. The results of environmental risk assessment indicated that sulfamethoxazole, ciprofloxacin and sarafloxacin, RQ>1, might pose a significant risk to aquatic organisms of the Datong Lake. The cumulative risk of S2, S3 and S6 were higher, and the main factors were enrofloxacin and sarafloxacin, sulfamethoxazole and ciprofloxacin, ciprofloxacin and sarafloxacin, respectively. The health risk indexes for adults and children, calculated for 11 antibiotics based on the acceptable daily intake through drinking water, ranged from 8.74×10-8 to 9.17×10-3, with children having a higher index than adults.