Department of Public Health, Anhui Medical University, Hefei, China.
Environ Toxicol Chem. 2013 Jan;32(1):165-73. doi: 10.1002/etc.2038. Epub 2012 Nov 26.
Silver nanoparticles (AgNPs) can exert negative effects on cell lines and embryos of freshwater fish. However, information on their distribution and long-term toxicity in adult species is limited. In the present study, a subchronic (14-d) toxicity test was designed to evaluate the bioaccumulation of AgNPs and their effects on the antioxidant defense system and histology of adult medaka. Purified AgNPs were well dispersed in water, and stability was maintained during the exposure period. After 14 d of exposure, a significant accumulation of Ag in the AgNP-dosed group was observed in the gill and intestinal tissues, with the highest levels found in the liver. Biochemical analysis indicated a dose-related decrease in the activity of lactate dehydrogenase and antioxidant enzymes in the liver, but not in the gills. However, dose-dependent increases in glutathione depletion and lipid peroxidation in the liver and gills were observed. Exposure to a graded dose of AgNPs also resulted in varying degrees of histological lesions in the tissues. Toxicological endpoints combined with metal distribution analysis suggested that AgNPs induced tissue-specific toxicity and that the liver is the organ most damaged by the Ag that might have been released from NPs. The oxidative damage caused by AgNPs may be associated with a large number of histological changes in the fish.
银纳米粒子（AgNPs）可能对淡水鱼类的细胞系和胚胎产生负面影响。然而，有关其在成年物种中的分布和长期毒性的信息有限。在本研究中，设计了一项亚慢性（14 天）毒性试验，以评估 AgNPs 的生物累积及其对成年斑马鱼抗氧化防御系统和组织学的影响。纯化的 AgNPs 在水中良好分散，并且在暴露期间保持稳定。暴露 14 天后，AgNP 处理组的鳃和肠组织中 Ag 的积累显著增加，肝脏中的含量最高。生化分析表明，肝脏中乳酸脱氢酶和抗氧化酶的活性与剂量有关下降，但在鳃中没有。然而，在肝脏和鳃中观察到谷胱甘肽耗竭和脂质过氧化与剂量有关的增加。暴露于梯度剂量的 AgNPs 也导致组织中出现不同程度的组织学损伤。毒理学终点结合金属分布分析表明，AgNPs 诱导了组织特异性毒性，并且肝脏是可能从 NPs 释放的 Ag 最受损的器官。AgNPs 引起的氧化损伤可能与鱼类大量的组织学变化有关。
