Fate and toxicity of nanoparticles in aquatic systems

Nanotechnology is a ground-breaking multidisciplinary field across a broad spectrum of basic and applied sciences for producing and applying nano-sized materials for innovative solutions. The use of nanomaterials in industrial applications, medical products, and consumers has increased repeatedly over the last few years, and these applications will likely continue to grow. In an aquatic ecosystem, nanoparticles take entry through a direct route that includes industrial discharge, disposal of wastewater treatment effluents, and indirect runoff from the soil. After reaching the aquatic environment, the nanomaterials are highly affected by their backdrops and subsequently go through various conversions like agglomeration, aggregation, dissolution, sulfidation, etc. The fate and the behavior of nanomaterials in the aquatic system not only depend on their physical-chemical properties but also on the pH, temperature, salinity, water hardness, and concentration of natural organic matter present in receiving water. In this review, emphasis has been given to the toxicological properties and potential risks of nanomaterials in terms of factors contributing to their toxicology, bioavailability, and accumulation in aquatic organisms as well as the environment. Furthermore, we summarize the published data on engineered nanoparticles’ effect on aquatic organisms. The issues related to the accumulation and penetration of nanoparticles in the aquatic organism, their toxic effect, and biotransformation along with the food web are also discussed. Since nanomaterials are being increasingly released into aquatic bodies, it is important to pay greater attention to their toxicity and how it affects the aquatic ecosystem. The nanomaterials are bioavailable to plants, resulting in trophic transfer, and they impact other organisms through biomagnification, as discussed in this review. To close the enormous information gap, extensive research on the interactions and impacts of NPs on different species belonging to different trophic levels of the aquatic environment and the destiny of NPs along the food chain of the ecosystem is urgently needed. Highlights The use of nanomaterial is in industrial applications, medical products, and consumers has increased repeatedly. The accidental release of NPs in the environment ultimately reaches the aquatic environment. A high concentration of these NPs negatively affects the organism at every trophic level. The NPs induced toxicity is mainly d