Environmental, Economic, and Social Viability of Nanoscale Zero-Valent Iron for Soil and Groundwater Remediation: A Sustainability Analysis from a Brazilian Perspective

Abstract The application of nanomaterials in environmental remediation has emerged as an innovative and promising technology. However, practical challenges continue to hinder their widespread implementation. This study aims to evaluate the feasibility of nanoremediation using nanoscale zero-valent iron (nZVI) in contaminated sites from a sustainability perspective, specifically in the Brazilian context. The research was conducted in an area contaminated with chromium, considering two distinct remediation scenarios: Scenario I, which involved unsaturated soil, and Scenario II, which involved saturated soil. Different remediation techniques were selected for each scenario. The viability of these techniques was assessed through life-cycle analysis, considering environmental, economic, and social impacts, as well as the overall sustainability of each remediation method. The functional unit for life-cycle analyses was defined as the remediation of 10 m 3 of soil and groundwater. The results indicate that nanoremediation with commercially available nZVI is not a viable option for unsaturated soils in Brazil. However, when nZVI is synthesized on-site using a green synthesis method, nanoremediation becomes a feasible remediation strategy. In contrast, in saturated soils, nanoremediation with commercial nZVI is both viable and sustainable for implementation in Brazil. Overall, this study advances the existing body of knowledge on the impacts and sustainability of nanoremediation by providing novel data and analyses, particularly in the context of Brazil. The viability of nanoremediation appears to be directly influenced by soil saturation levels and the quantity of nanomaterial used in the remediation process.