Trophic Transfer of Metal Nanoparticles in an Aquatic Food Chain Diminishes their Toxicity Disparities

Engineered nanoparticles (ENP) threaten aquatic ecosystems as they are increasingly released into the aquatic environment, which is the sink for most contaminants, throughout their life cycle. How the food web responds to ENPs or how they shape the food web remains unclear. Here, we report the environmental behavior and toxicity of four ENPs in an aquatic food chain, focusing on their uptake, depuration, and trophic transfer efficiency. While no bioaccumulation or biomagnification was observed, the properties and biotransformation of the ENPs significantly influenced their uptake and depuration rates in the Eubranchipus vernalis-Oryzias latipes food chain. We also highlight the impact of particle properties and exposure pathways on toxicity, revealing that oxidative stress leads to mitochondrial damage, contributing to cellular dysfunction in various tissues. Sulfidation and surface coating accumulation strongly diminish and converge the ENP toxicity to O. latipes in terms of ENP property disparity. For the first time, these findings suggest that the food chain strongly modulates aquatic toxicity based on the accumulation and transformation of different ENP components, which may shed light on the understanding of the environmental fate of ENPs.