Copper Oxide Nanoparticles as an Emergent Threat to Aquatic Invertebrates and Photosynthetic Organisms: A Synthesis of the Known and Exploration of the Unknown

Purpose of Review: Nanotechnology has transformed various aspects of contemporary life, technology, and research. This is evident in the rising global demand for and use of nanoparticles, leading to a corresponding increase in their discharge into the environment through diverse human activities. In the last few years, the rampant use of copper oxide nanoparticles (CuO-NPs) has piqued interest. Recent Findings: CuO-NPs are widespread and tend to remain in the environment, enabling them to increase in concentration through the food chain and ultimately impact human health. When aquatic organisms are exposed to CuO-NPs, it may cause oxidative stress. This can change proteins, cause lipid peroxidation, and damage DNA. This can ultimately cause cytotoxicity, genotoxicity, and epigenetic changes. Summary: CuO-NPs produce reactive oxygen species (ROS), which can have various consequences for organisms and the environment. The objective of the review was to introduce a refreshed audit on the ecotoxicity, a comparison of systems related to CuO-NPs, and an assessment of the safe limit to prevent chronic toxicity across different taxa: aquatic invertebrates, plants, and algae. Additionally, the article briefly discusses the existing knowledge gaps in this area and makes recommendations for future research.