Micro- and nanoplastics in soil ecosystems: Analytical methods, fate, and effects

As emerging contaminants, microplastics and nanoplastics (MPs/NPs) are increasingly widespread in soil environment. The present paper reviews available analytical methods for detecting MPs/NPs in soil and plants, and examines the migration processes of MPs/NPs at multiple interfaces as well as the potential toxic effects of MPs/NPs. Without standard methods to trace MPs/NPs in different environmental compartments, indoor simulation experiments were mainly adopted in previous studies, differing greatly from MPs/NPs in actual environments. Therefore, we propose that new research should particularly 1) focus on realistic environmental concentrations and surrogates that mimic types, shapes, and sizes of MPs/NPs in natural environments; 2) develop novel methods to improve our understanding of multi-interface migration and transformation of MPs/NPs in the soil-plant system; and 3) advance towards an in-depth assessment of potential toxic effects of MPs/NPs on soil organisms to provide a scientific basis for the effective control of MPs/NPs pollution.