水体中铊对泥鳅外周血红细胞的遗传毒性

Genotoxicity of thallium in water on Misgurnus anguillicaudatus peripheral red blood cells

铊(Tl)是剧毒的重金属元素。含铊矿产资源在开发利用过程中会释放铊,对生态环境和人体健康造成威胁。目前我国尚缺乏水环境中铊的安全标准。利用泥鳅Misgurnus anguillicaudatus红细胞微核技术研究水体中铊的遗传毒性。结果表明:水体中铊含量在0～1μg·L-1范围内,随铊质量浓度的增加,泥鳅红细胞产生微核以及核突起、凹陷等各种核异常现象;微核率、核异常率及核空泡率等3项指标随铊质量浓度升高而升高,且呈显著或极显著正相关。这3项指标作为铊胁迫下泥鳅红细胞毒害程度的依据具有可行性。当水体铊质量浓度为0.3μg·L-1时,微核率、核异常率及核空泡率均极显著高于对照。将铊质量浓度0.3μg·L-1作为泥鳅红细胞发生突变的阈值。

Thallium （T1） is a toxic heavy metal. Water pollution of thallium released from thallium con-taining mines will lead to adverse environment effects and human health problems. In order to set found-ations to perfect the water quality indexes and ecological risk assessment, genotoxicity of thallium on Misgurnus anguillicaudatus peripheral red blood cells is studied. The results show that the frequency of red blood cell micronucleus rises companied by thallium contents increasing from 0.1 μg·L^-1 in water. At the same time, the frequencies of abnormal nucleus and vacuolar nucleus increase either. Especially, the frequencies of micronucleus, abnormal nucleus and vacuolar nucleus under thallium 0.3μtg·L^-1 in water are different significantly from control sample. The correlation analysis indicates that significant positive corre-lation exists among frequency of red blood cell micronuclei, abnormal nuclei and vacuolar nuclei. These three indexes can be used commonly to determine the genotoxicity of thallium on cells. Finally, the thres-hold of thallium in water on Misgurnus anguillicaudatus peripheral red blood cells is determined by 0.3μg·L^-1.