三丁基锡(TBT)对罗氏沼虾的毒性效应

Toxicity effect of tributyltin(TBT)on Macrobrachium rosenbergii

将罗氏沼虾(Macrobrachium rosenbergii)幼虾和成虾暴露在不同浓度的三丁基锡(tributyhin,TBT)溶液中,进行急性和慢性毒性实验,通过组织病理学观察研究TBT对罗氏沼虾的毒性效应。结果表明:TBT对罗氏沼虾幼虾和成虾的96h半致死浓度(96h LC50)分别为51和376μg.L-1,安全浓度(SC)分别为5.1和37.6μg.L-1;罗氏沼虾幼虾暴露在浓度分别为1.25、2.5和5μg.L-1的TBT溶液中30d后,其体重和体长均极显著低于对照组(P<0.05);罗氏沼虾成虾暴露在浓度分别为2、8和32μg.L-1的TBT溶液中30d后,生长速度虽未见明显差异,但鳃和肝胰脏组织结构均出现异常;TBT浓度高于8μg.L-1时,处理组鳃上皮细胞肿胀,支持细胞中的细胞核萎缩,鳃血窦中血细胞聚集,肝胰脏细胞肿大,出现空泡化,细胞中出现细小颗粒;TBT浓度达32μg.L-1时,罗氏沼虾肝胰脏细胞空泡化程度严重,细胞核消失,部分细胞解体并出现坏死区;表明一定剂量的TBT对罗氏沼虾的鳃和肝胰脏有明显的毒性效应。

Macrobrachium rosenbergii juveniles and adults were exposed to different concentration tributyltin（TBT）to study the acute and chronic effects of TBT on the growth of M.rosenbergii and on the histological structure of the shrimp＇s gill and hepatopancrese.For the juvenile and adult of M.rosenbergii,the 96 h median lethal concentration（96 h LC50）was 51 and 376 μg·L-1,and the safe concentration（SC）was 5.1 and 37.6 μg·L-1,respectively.Compared with the control group,the body weight and length of juvenile M.rosenbergii after exposed to 1.25,2.5,and 5 μg·L-1 of TBT for 30 d decreased significantly（P0.05）,while the growth of adult M.rosenbergii after exposed to 2,8,and 32 μg·L-1 of TBT for 30 d was less affected,but the histological structure of gill and hepatopancrese appeared abnormal.When the TBT concentration reached 8 μg·L-1,the gill epithelial cells of treated M.rosenbergii swelled,nucleus in support cells contracted,and blood cells in blood cavity aggregated.Correspondingly,liver cells swelled and vacuolated.When the TBT concentration reached 32 μg·L-1,liver cells vacuolated more seriously,nucleus disappeared,and parts of the cells disaggregated and appeared necrosis,showed that definite concentration TBT had strong toxicity to the gill and hepatopancrese of M.rosenbergii.