Aftershocks of the Samarco disaster: diminished growth and increased metal content of Raphanus sativus cultivated in soil with mining tailings

The collapse of the Fundão tailings dam Samarco mining complex in Mariana, Brazil, was largest disaster world to date with many socio-economic and environmental impacts. Soil affected by severely altered negative impacts for agriculture. We tested whether diluting organic soil would eliminate or at least attenuate ecotoxic effects on plant development performance. cultivated radish, Raphanus sativus, substrates containing different proportions soil: pure (T100%); 2) tailings75% + soil25% (T75%); 3) tailings50% soil50% (T50%); 4) tailings25% soil75% (T25%), 5) (Soil100%, control). There were large differences quality parameters between 100% treatment (T100%) control (Soil100%), as well some most diluted - T25% (Ca2+, Fe, Mn) relation treatment. Although dilution improved radish development, there lower productivity (leaf area, total biomass, root/tuber biomass) than (control). also significantly higher amounts bioaccumulated metals tubers grown tailings, even when Fe content T75% Mn content. These results present a worrisome scenario human communities region Doce river, consumption crops produced contaminated is not recommended due potential toxicological from high metal concentrations.