Centro Interdisciplinar de Energia e Ambiente (CIENAM), Instituto de Química, Universidade Federal da Bahia. Rua Barão de Jeremoabo, s/n, Ondina, 40170-115, Salvador, BA, Brazil.
Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense. Av. Alberto Lamego 2000, 28015-620, Campos dos Goytacazes, RJ, Brazil.
Sci Rep. 2017 Sep 6;7(1):10706. doi: 10.1038/s41598-017-11143-x.
The impacts of the SAMARCO iron tailing spill along more than 650 km, between the dam and the plume of the Doce River in the Atlantic, were assessed by the determination of toxic metals. The tailing spill caused a substantial increase in suspended sediment loads (up to 33,000 mg L), in addition to large depositions of waste along the Doce basin. The highest estimated transport of dissolved metals was observed for Fe (58.8 μg s), Ba (37.9 μg s) and Al (25.0 μg s). Sediments reached the highest enrichment factors (EFs) for Hg (4,234), Co (133), Fe (43), and Ni (16), whereas As (55), Ba (64), Cr (16), Cu (17), Mn (41), Pb (38) and Zn (82) highest EFs were observed for suspended particulate matter (SPM). Iron, As, Hg, Mn exceeded sediment quality guidelines. Therefore, the risk of occurrence of adverse effects is highly possible, not only due to the dam failure, but also due to the Fe mining and the artisan Au mining. Heavy rain episodes will likely cause enhanced erosion, remobilization, and transport of contaminated particles, sustaining high inputs of SPM and metals for the years to come and threatening the ecosystem services.
对萨马科铁矿尾矿泄漏事件的影响进行了评估，范围从大坝到多斯河的大西洋羽流，长达 650 多公里。通过测定有毒金属含量来评估尾矿泄漏事件的影响。尾矿泄漏导致悬浮泥沙负荷显著增加（最高达 33000mg/L），多斯河流域还沉积了大量废物。溶解态金属的最大估计运移量为 Fe（58.8μg/s）、Ba（37.9μg/s）和 Al（25.0μg/s）。沉积物的汞（4234）、钴（133）、铁（43）和镍（16）的富集因子（EF）最高，而悬浮颗粒物（SPM）中的砷（55）、钡（64）、铬（16）、铜（17）、锰（41）、铅（38）和锌（82）的 EF 最高。铁、砷、汞和锰超过了沉积物质量基准。因此，不仅由于大坝决堤，而且由于铁矿开采和手工金矿开采，发生不利影响的风险极有可能很高。强降雨事件可能会导致污染颗粒的侵蚀、再移动和运输增加，在未来几年内将持续输入大量 SPM 和金属，威胁生态系统服务。
