Impacts of metallic nanoparticles and transformed products on soil health

Widespread usage of nanotechnology has increased the release of metallic nanoparticles (MNPs) into the environment, which are mostly engineered. Agricultural soil is one of the most important sinks for MNPs. While numerous studies have focused on understanding the phytotoxicity of MNPs, and the extent and pathways of their accumulation in plants, the impacts of MNPs on soil health are only gaining attention recently. A comprehensive review summarizing the interactions of MNPs with soil is yet available. This review aims to fill the gap by evaluating the impacts of common MNPs on soil properties. Specifically, we examined the effects of MNPs on soil physical properties, the availability of plant nutrients and heavy metals from the perspective of food safety and security, as well as soil microbial ecology and microbial community associated with nutrient and carbon cycling. We underscored the impacts of environmental transformation of MNPs on soil health. Compared with soil physical and chemical properties, biological parameters of soil health are more susceptible to the impact of MNPs. Overall, the effects of MNPs and their transformed products on soil health vary with soils, MNPs, and exposure duration and dosage.