ABSTRACT
In order to perform a proper assessment of the environmental risk associated with the technological deployment, a number of issues should be comprehensively evaluated and understood: degree of toxicity caused by nanoparticles (NPs), toxicity mechanisms involved, fate and transport of NPs, impact on microbial communities, and so on. This chapter discusses these features and reviews both methodological approaches and results of related research studies performed in this field. Literature shows a comprehensive set of studies dealing with the investigation of parameters affecting toxicity caused by nanozerovalent iron (nZVI). Increasing NPs dosage seems to be related to an increasing toxic response, unless a high concentration of NPs induces iron aggregation leading to less colloidal stability, higher sedimentation rates, and consequently, milder toxic effects. The classical methodology for environmental risk assessment can be employed, on the basis of a conceptual site model defined and characterized by the sources, pathways, and potential receptors of nZVI.
