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Phytoextraction of rare earth elements (REE) from contaminated soils has gained importance during the last few decades. The Poços de Caldas municipality in Brazil is known for its mineral richness, including large reserves of REE. In this study, we report light REE (La, Ce, Sm, Pr, and Nd) in soils and plants collected in an area. Composite soil samples and plant individuals were collected, and total concentrations of LREE in soils were determined by wavelength dispersive X-ray fluorescence (WDXRF). The plant available LREE concentrations in soils were estimated upon the acetic acid method (F1 fractions) of the stepwise sequential extraction procedure, together with plant content that was analysed by inductively coupled plasma mass spectrometry (ICP-MS). The total sum concentrations of tested LREE in soils varied from 5.6 up to 37.9 g kg−1, the bioavailable fraction was ca. 1%, and a linear relationship was found between them. The only exception was Sm, whose availability was lesser and did not show a linear relationship. The concentration of LREE in non-accumulator plants varied from 1.3–950 mg kg−1 for Ce, La 1.1–99 mg kg−1, Sm 0.04–9.31 mg kg−1, Pr 0.1–24.1 mg kg−1, and Nd 0.55–81 mg kg−1. The concentration of LREE among shoots did not show a linear relation either with the available fraction or total content. The screening also revealed Christella dentata (Forssk.) Brownsey & Jermy, Thelypteridaceae family, as a promising hyperaccumulator species. The concentrations of LREE among shoots of six individuals of this species were in the ranges from 115 to 1872 mg kg−1 for Ce, La 190–703 mg kg−1, Sm 9–48 mg kg−1, Pr 32–144 mg kg−1, and Nd 105–478 mg kg−1. [ABSTRACT FROM AUTHOR]

In 2015, a major technological disaster occurred in Brazil: The breakdown of a dam in the city of Mariana. When discharged along the Rio Doce basin, the ore debris have generated negative externalities that affected two states: Minas Gerais and Espírito Santo. The objective of this work is to evaluate the impact of the disaster on the economic performance of these States. To this end, synthetic controls were constructed to identify the behavior of the States in the absence of the disaster. In terms of the general manufacturing production, Espírito Santo State had a reduction in 18.22% in comparison with the situation before the disaster, whereas there was no significant impact in Minas Gerais. As for the extractive mineral manufacturing production, both states showed significant decrease of this index as a result of the disaster: Espírito Santo state had a reduction in 25,01%, whereas Minas Gerais exhibited a decrease in 15,58%. [ABSTRACT FROM AUTHOR]