Rare earth elements as tracers of iron ore tailings on the Brazilian eastern continental shelf

Abstract

Iron ore tailings are stored in large dams and pose risks to the environment around the world. In Brazil, the rupture of these dams has become frequent and generated environmental and social concern. Rare earth elements are good tracers of sediment sources and our results indicated chronic contamination of the seabed sediment from the marine region affected by the Fundão Dam tailings since 2015, including areas of environmental protection. This research, carried out between November 2018 and September 2021, with a database of 575 samples, showed a greater contaminated material in the marine region adjacent to the Doce River mouth. Although data suggest prior mining contamination of the Doce River basin, the Fundão episode was an empirical and massive example of the environmental damage caused by these human activities over the centuries, showing that the impact remains in the shallow marine environments for years.

Second Fundão Dam Rupture Science Meeting: Updating the science

“…It was also not clear whether this condition had persisted. It also appears that rare earth elements can help resolve the coastal distribution of residual tailings (Cagnin et al, 2023).…”