Toxicity of copper oxide nanoparticles on the Asian clam Corbicula fluminea using multiple biomarkers

The extensive use of nanoparticles (NPs) increases the possibility of their deposition into water ecosystems and endangering aquatic life. Thus, this study aimed to assess the acute effect of copper oxide nanoparticles (CuO NPs) on the freshwater clam, Corbicula fluminea. Biochemical, histopathological, and genotoxic biomarkers were examined to achieve this purpose. Clams were exposed to 1.8 and 6.6 mg/l of CuO NPs for 96 h. By comparison with control clams, a significant increase in both malondialdehyde (MDA) and nitric oxide (NO) levels occurred with a concomitant decrease in catalase (CAT) and acetylcholinesterase (AChE) activities and reduced glutathione (GSH) content in clam’s tissues treated with both sub-lethal concentrations. Histopathological alterations were observed in the mantle, gills, digestive glands, and gonads of C. fluminea exposed to both sub-lethal concentrations and the histopathological indices for all the reaction patterns in the examined tissues were significantly higher in clams exposed to the higher concentration of CuO NPs (6.6 mg/l). DNA damage evaluated by changes in RAPD profiles. These findings revealed that CuO NPs have a toxicological impact on Corbicula fluminea even after a short period of exposure, thereby immense care should be taken regarding its use.