Nano-pesticides in agroecosystems: Environmental fate, ecotoxicological impacts, and sustainable risk mitigation strategies.

Nano-pesticides have emerged as an important class of emerging environmental chemicals with potential to improve agricultural efficiency while reducing bulk chemical inputs. Despite these advances, their environmental fate, transport mechanisms, and ecotoxicological implications remain insufficiently characterized. The present review critically examines the transformation pathways of nano-pesticides in soil, aquatic environments, and non-target organisms (NTOs). Key processes such as sorption-desorption dynamics, aggregation behavior, dissolution, and persistence are discussed with particular emphasis on bioavailability, trophic transfer, and the potential for bioaccumulation in NTOs, including soil invertebrates, pollinators, aquatic biota, and microbial communities. Emerging evidence from mesocosm and field studies suggests that exposure to nano-pesticides can disrupt soil nutrient cycling, enzyme activity, and organic matter decomposition, thereby alter ecosystem functions and posing long-term ecological risks. Furthermore, current regulatory frameworks remain largely based on acute laboratory toxicity assays, which fail to capture sublethal, chronic, or multigenerational effects, nor do they reflect environmentally relevant exposure pathways. To address these limitations, this review highlights advances in nano-specific ecotoxicity testing protocols, integrating omics-based tools, and enhancing ecological risk assessment frameworks tailored to nano-enabled agrochemicals. We further discuss the potential of predictive modeling and machine learning (ML) to support multi-season exposure forecasting and scenario-based risk evaluation. Finally, we highlight sustainable mitigation strategies, including nano-bioformulations, green synthesis approaches, and agroecological practices, which can reduce nanoparticle (NP) persistence, minimize off-target effects, and enhance soil microbial functions. This review presents a science-based framework for the sustainable deployment and regulation of nano-pesticides in agroecosystems, balancing agricultural productivity with ecosystem protection and environmental stewardship.