Levels and environmental risks of rare earth elements in a gold mining area in the Amazon

• Published in: Environmental research Vol. 211; p. 113090
• Main Authors: Pereira, Wendel Valter da Silveira, Ramos, Sílvio Junio, Melo, Leônidas Carrijo Azevedo, Braz, Anderson Martins de Souza, Dias, Yan Nunes, Almeida, Gabriela Vilhena de, Fernandes, Antonio Rodrigues
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01-08-2022
• Subjects: Artisanal gold mining; Carajás mineral province; Eastern Amazon; Emerging contaminants; Environmental contamination; Artisanal gold mining; Environmental contamination; Carajás mineral province; Emerging contaminants; Eastern Amazon
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2022.113090

Artisanal gold (Au) mining may have increased the concentrations of rare earth elements (REEs) in the Serra Pelada mine (southeastern Amazon, Brazil), which has not been evaluated so far. The objectives of this study were to determine the concentrations of cerium (Ce), lanthanum (La), scandium (Sc), and yttrium (Y) in the surroundings of the Serra Pelada mine, as well as the environmental risks associated with these elements. Therefore, 27 samples were collected in agricultural, forest, mining, and urban areas, and submitted to chemical and particle size characterization. The concentrations of REEs were quantified by inductively coupled plasma mass spectrometry (ICP-MS) and used to estimate pollution indices and environmental risks of the studied elements. All REEs had higher levels in the anthropized areas when compared to the forest area, except Sc in the mining and urban areas. Pollution load indices revealed that all areas are contaminated (>1) by the combined effect of REEs, especially the agricultural areas (index of 2.3). The element of greatest enrichment in the studied areas was Y, with enrichment factors of 18.2, 39.0, and 44.4 in the urban, agriculture, and mining areas, respectively. However, the potential ecological risk indices were low (<150) in all areas, indicating that there are no current environmental risks by the studied REEs.
•Rare earth elements (REE) were evaluated in an Amazonian gold mine (Serra Pelada).•The highest REE contamination was found in agricultural areas.•The element with the highest degree of enrichment was yttrium.•Despite the concentrations, there are no environmental risks from the studied REEs.