Liu Wenming, Qiu Hanxun, Yan Yulian, Xie Xiaojun
Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China.
Toxics. 2021 Aug 29;9(9):202. doi: 10.3390/toxics9090202.
The amounts of cadmium in multiple organs and the amounts of Na and Ca in the carcass were measured in dead and surviving southern catfish exposed to different concentrations of Cd. The 96 h median lethal concentration was 6.85 mg/L. The Cd content and Cd accumulation rate were positively correlated with Cd exposure concentrations, and there were significant differences between dead and surviving individuals, indicating that both Cd content in tissues and Cd accumulation rates were correlated with mortality. Cd levels in the liver of dead fish were saturated. A lethal threshold for Cd concentration in the whole fish was obtained. Bioconcentration factors for Cd did not decrease with increasing exposure. Acute exposure to waterborne Cd caused a significant decrease in the ion content of the fish carcass. There was a significant difference between the Na content of the carcass of dead fish (34.54 μmol/g wet weight) and surviving fish (59.34 μmol/g wet weight), which was not the case with the Ca content, indicating that the lethal toxicity of Cd was probably related to the decrease in Na content. Collectively, these results suggest that whole-fish Cd concentration and carcass Na content can be useful indicators of fish acutely exposed to Cd.
在暴露于不同浓度镉的死亡和存活南方鲇中，测量了多个器官中的镉含量以及鱼体中的钠和钙含量。96小时半数致死浓度为6.85毫克/升。镉含量和镉积累率与镉暴露浓度呈正相关，死亡个体和存活个体之间存在显著差异，表明组织中的镉含量和镉积累率均与死亡率相关。死鱼肝脏中的镉水平已饱和。得出了全鱼镉浓度的致死阈值。镉的生物富集系数并未随暴露增加而降低。急性暴露于水中的镉会导致鱼体离子含量显著下降。死鱼（34.54微摩尔/克湿重）和存活鱼（59.34微摩尔/克湿重）鱼体中的钠含量存在显著差异，而钙含量则不然，这表明镉的致死毒性可能与钠含量的降低有关。总体而言，这些结果表明全鱼镉浓度和鱼体钠含量可作为鱼类急性暴露于镉的有用指标。
