Polystyrene microplastics alter the accumulation and elimination dynamics of silver nanoparticles in <i>Daphnia magna</i>

Environmental context Microplastics are widespread aquatic contaminants that can alter the environmental behavior of co-occurring pollutants. This study shows that polystyrene microplastics substantially modify silver nanoparticle bioaccumulation in Daphnia magna, increasing waterborne uptake, accelerating elimination and ultimately elevating predicted steady-state silver burdens. These findings can improve understanding of microplastic–nanoparticle interactions and can support future assessments of contaminant fate and ecological risk in aquatic systems.