Aims and Background: The growing use of nanoparticles in different sections caused environmental concerns. Cobalt nanoparticles as nanoparticles that limited information are available about their effects of toxicity on aquatic organisms. Therefore, the aim of this research was the effect of short term exposure to cobalt ion and nanoparticle on gill of zebrafish (Danio rerio) under laboratory condition. Methods and Materials: In this study, five concentration of Co nanoparticles and Co ions non-lethal were used that the including 1, 10, 32, 100, and 200 mg/l with the control group (no chemical). After 8 days exposure to Co nanoparticles and Co ions, the samples of fish gill were taken. To study classical histology, after preparation of the samples with haematoxylin - eosin staining, the slides were photographed by an optical microscope. Results: The results of this study showed that the Co nanoparticles and Co ions caused damages such as clubbing the head string, edema, Hyperplasia, fusion, and aneurysms in gills of zebra fish. Also, levels of tissue damages in gill on the both of Co nano- and ions were dose-dependent. Conclusion: According to findings of this study, levels of damages caused in Co nanoparticles were higher than the Co ions condition. Also, both of Co nano- and ions can cause serious damages in zebra fish gill tissue and therefore should be prevented release of this material to aquatic ecosystems.

Keywords: Nanoparticles, ions, Histopathology, Gill, Nanotoxicology, Zebrafish

Full-Text [PDF 730 kb]   (1520 Downloads)