Comparative effects of copper oxide nanoparticle morphology (nanorods vs. nanospheres) on the metabolism and swimming performance of Oreochromis niloticus

ions. These findings underscore the critical role of morphology, colloidal stability, and solubility in the ecotoxicological assessment of nanomaterials. We conclude that CuO-NPs, particularly in the form of nanorods, pose a significant risk to fish physiology and locomotor performance, reinforcing the need to integrate morphological, physiological, and behavioral endpoints in environmental risk assessment and regulatory policies for the safe use of these nanomaterials.