Copper Nanoparticles in Aquatic Environment: Release Routes and Oxidative Stress-Mediated Mechanisms of Toxicity to...

The final recipient of nanoparticles, including various types of copper-based nanoparticles (Cu-based NPs), is the aquatic environment. Their increased production, especially as a component of antimicrobial agents, raises concerns about uncontrolled environmental release and subsequent ecological risks. The high reactivity of Cu-based NPs enables interactions with biotic and abiotic environmental components, leading to bioaccumulation and disorders in living organisms, such as fish in various life stages, especially in embryos or hatchlings. Increasing concentration of Cu-based NPs causes various toxic effects, mainly through the induction of oxidative stress. These effects include impairment of antioxidant mechanisms, as well as damage to genetic material, cells and tissues, growth retardation, metabolic disorders, increased mortality, or hatching inhibition. The aim of this review is to describe the release routes of Cu-based NPs and their adverse effects on fish, while emphasizing the need for further research on their toxicity and measures to control their release to the environment. Given the limited data on the toxicity of Cu-based NPs, especially concerning sensitive fish developmental stages, further studies are required.