Engineered nanoparticles in aquatic systems: Toxicity and mechanism of toxicity in fish

Engineered nanoparticles (ENPs) have gained attention in the world of technology due to their diverse and unique properties compared to their pristine counterparts. Their tunable physical, chemical, and biological properties make them applicable in various fields including the environment, agriculture, and medicine or biotechnology. Consequently, there is a rapid increase in ENPs waste in the environment. This raises questions about what will become of the waste and the potential environmental toxicity and health risks. Knowledge of their fate in the environment helps control/manage their usage mostly taking advantage of the initiatives of the circular economy (reuse, reduce and recycle). In this review, the fate of ENPs in aquatic systems is highlighted. Different ENP transformations in aquatic systems are explained. Additionally, uptake, internalization, and toxicity in fish are elaborated together with some toxicity mechanisms. Finally, the biomagnification of these ENPs up the food chain is illustrated considering that fish are a good source of nutrients and play a major role in addressing food security issues worldwide. The information used in this review was obtained mostly from published articles (obtained through google scholar) and other internet sources with the keywords being ENPs transformation in natural aquatic systems, ENP toxicity to fish, mechanism of ENP toxicity to fish, and bioaccumulation of ENPs in fish.(c) 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).