Bioavailability of Engineered Nanoparticles in Soil Systems

Abstract

Nanotechnologies form a field of research that is still emerging with major gaps in knowledge regarding the behavior and potential toxicological risks of engineered nanoparticles (ENPs) in soils. While most of the studies are conducted in porous media (quartz and glass beads) and culture media, less frequently are the studies carried out in natural soils. However, the complex interactions occurring in soils, mediated by both soil components and soil organisms, are essential in bioavailability processes. Therefore, this paper is intended to highlight particularly the bioavailability of ENPs in soils. The potential release pathways of ENPs to soils are described and are faced with a lack of specific regulation and definitive nomenclature. This paper reviews a number of studies regarding ENP toxicological bioavailability on microorganisms and microfauna, mesofauna, and macrofauna inhabiting the soil, as well as on soil-plant systems. The paper especially discusses ENP behavior in soils that affect ENP bioavailability to the edaphic biota. Particular attention is paid to the factors regulating these processes [i.e., (1) ENP-dependent factors, (2) soil properties, and (3) soil components], focusing on organic matter.