Mariana's Disaster: diagnosis of contamination, remediation strategies, and reuse of iron ore tailings

• Grant number: 22/12966-6
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2023
• End date: August 31, 2024
• Field of knowledge: Physical Sciences and Mathematics - Geosciences
• Principal Investigator: Tiago Osório Ferreira
• Grantee: Tiago Osório Ferreira
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated researchers: Alexys Giorgia Friol Boim ; Amanda Duim Ferreira ; Diego Barcellos ; Hermano Melo Queiroz ; Owen Duckworth ; Renata Cristina Bovi ; Samantha Ying ; Xose Luis Otero
• Associated research grant(s): 23/01493-2 - Evaluation of the impacts and risks to human health caused by exposure to tailings from Fundão dam failure in Mariana/MG, AP.R
• Associated scholarship(s): 24/08159-3 - Assessment of risks to human health due to the consumption of food produced in the Rio Doce estuary, BP.IC

Abstract

Iron (Fe) mining plays a crucial role in the global economy. However, the - increasingly frequent - failures of dams containing mining tailings require environmentally safe and economically sustainable solutions. The mining tailings deposition over natural and agricultural ecosystems raises concerns about risks to human health, especially in estuarine environments, where the dissolution of Fe oxides (i.e., the main constituent of tailings), may lead to associate potentially toxic elements (EPTs) release. Seven years after the "Mariana's Disaster", the risk to human health owing to the consumption of food produced in soils impacted by mining tailings in the Rio Doce estuary has not been evaluated. In addition, the accumulation of EPTs in non-food plants implies an opportunity for environmental decontamination. Accordingly, phytoremediation and phytomining stand out as alternatives for the remediation and reuse of Fe ore tailings, respectively. However, the phytoextraction capacity of these plants depends on their characteristics (e.g., high biomass production) and the bioavailability of the element in the soil or waste. In this sense, chemically and/or biologically assisted-phytomining can be applied to increase the potential of the species. Given the above, this proposal aims to: i) Quantify the total contents of EPTs in soils, roots, leaves, and fruits, as well as contents of human oral bioaccessibility in soils and fruits of plants grown in the Rio Doce estuary; ii) Evaluate the phytoremediation potential of EPTs in situ by Typha domingensis from assisted-phytoremediation strategies tested in isolation and collectively; iii) Apply agromining strategies in Fe ore tailings to obtain bio-ore. The present project will provide an integrated understanding of the EPTs effect on plants cultivated in the Rio Doce estuary, and support mitigation measures for areas affected by iron ore tailings. (AU)