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目的 探究某城市不同污染程度地表水中有机污染物的致突变性,初步探讨蓝棉的吸附效能.方法 于2010年11月,选择某城市5个采样点,其中,A、B点的水样分别为流经该城市上游乡村和郊区的河水,C点的水样为某污水处理厂进水口污水,D、E点的水样分别为某自来水厂的水源水和出厂水.将各采样点40L水样以15 ml/min流速经蓝棉过滤后,用甲醇洗脱经蓝棉吸附的有机提取物,配置成10 L/ml浓度储备液.将储备液设置0.1、1 L/皿剂量组,选用组氨酸营养缺陷型鼠伤寒沙门菌TA98和TA100菌株进行Ames试验.选取储备液对金鱼腹腔进行一次性注射染毒,染毒容量为10 μl/g,并设阴性、阳性对照,进行金鱼鱼鳃细胞微核试验和金鱼外周血细胞彗星试验.结果 Ames试验显示,5个采样点受检水样中主要存在移码型间接致突变物,C点的水样有机提取物Ames试验阳性最强;金鱼外周血细胞彗星试验显示,与阴性对照组相比,C点与E点的水样有机提取物染毒组金鱼外周血细胞尾矩增加,差异有统计学意义(P＜0.05);金鱼鱼鳃细胞微核试验显示,C点的水样有机提取物染毒组金鱼鱼鳃细胞微核率升高,差异有统计学意义(P＜0.05).结论 在一定剂量浓度下,该城市部分受检水样中有机提取物具有致突变作用,污水处理厂进水口水样的有机提取物致突变性较强,水体污染程度较为严重.蓝棉对受检水样中有机污染物具有较好的富集作用,主要吸附移码型间接致突变物.“,”Objective To know the mutagenicity of organic contaminants extracted from surface water with different contamination levels and the adsorption efficiency of blue cotton.Methods The water samples were collected from five sampling sites in a city in November 2010.Sample A and sample B were respectively collected from the upstream of rivers flowing through the countryside and the suburb of the city,and sample C was collected from the sewage plant inlet,and sample D and E were the source water and finished water of a water plant respectively.A total of 40 L water sample passed through blue cotton at a flow rate of 15 ml/min.The adsorbents in blue cotton were extracted with methanol,and then redissolved in DMSO at concentration of 10 L/ml.Histidine auxotroph Salmonella typhimurium TA98 and TA100 strains were used in Ames assay,and the exposure concentrations were 0.1 L/dish and 1.0 L/dish for the extracted organic contaminants eluted by methanol.Micronucleus test and the peripheral erythrocytes comet assay were conducted by treating goldfish with 10 μl/g extracts through single intraperitoneal injection.Negative and positive control groups were treated with DMSO and methyl methylsulfonate respectively.Results Ames test showed dominant frameshifi mutagens in these five water samples,and the organic extracts from the sewage plant water showed the strongest positive.The tail moment of goldfish peripheral erythrocytes in the group exposed to the organic extracts from the sewage plant water and tap water samples were significantly higher than those in the negative control group (P＜0.05).The micronucleus rate of goldfish gills in the group exposed to the organic extracts from the sewage plant water was significantly higher compared with the negative control group (P＜0.01).Conclusion At a certain dose,organic extracts in several water samples collected from the investigated city have potential mutagenic activity and the organic extracts from the sewage plant water showed the strongest mutagenic effect.Blue cotton has a better enrichment effect on the organic contaminants and it mainly adsorbs frameshift indirect mutagens.