Laboratório de Geoquímica Ambiental e Poluição Marinha, Departamento de Oceanografia e Ecologia, Universidade Federal do Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, Vitória, ES 29055-460, Brazil.
Laboratório de Geoquímica Ambiental e Poluição Marinha, Departamento de Oceanografia e Ecologia, Universidade Federal do Espírito Santo, Av. Fernando Ferrari, 514, Goiabeiras, Vitória, ES 29055-460, Brazil.
Sci Total Environ. 2021 May 15;769:144532. doi: 10.1016/j.scitotenv.2020.144532. Epub 2021 Jan 7.
In the context of the Doce river (Southeast Brazil) Fundão dam disaster in 2015, we monitored the changes in concentrations of metal(loid)s in water and sediment and their particulate and dissolved partitioning over time. Samples were collected before, during, and after the mine tailings arrival to the Doce river estuary (pre-impact: 12, 10, 3 and 1 day; acute stage: tailing day - TD and 1 day after - DA; chronic stage: 3 months and 1 year post-disaster). Our results show that metal(loid) concentrations significantly increased with time after the disaster and changed their chemical partitioning in the water. 35.2 mg Fe L and 14.4 mg Al L were observed in the total (unfiltered) water during the acute stage, while aqueous Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se and Zn concentrations all exceeded both Brazilian and international safe levels for water quality. The Al, Fe and Pb partitioning coefficient log (K) decrease in the acute stage could be related to the high colloid content in the tailings. We continued to observe high concentrations for Al, Ba, Cd, Cr, Cu, Fe, V and Zn mainly in the particulate fraction during the chronic stage. Furthermore, the Doce river estuary had been previously contaminated by As, Ba, Cr, Cu, Mn, Ni and Pb, with a further increase in sediment through the tailing release (e.g. 9-fold increase for Cr, from 3.61 ± 2.19 μg g in the pre-impact to 32.16 ± 20.94 μg·g in the chronic stage). Doce river sediments and original tailing samples were similar in metal(loid) composition for Al, As, Cd, Cr, Cu, Fe, V and Zn. As a result, these elements could be used as geochemical markers of the Fundão tailings and considering other key parameters to define a baseline for monitoring the impacts of this environmental disaster.
在 2015 年巴西东南部多塞河丰当大坝灾难的背景下，我们监测了水中金属（类）浓度以及它们的颗粒态和溶解态分配随时间的变化。在多塞河河口（预冲击：12、10、3 和 1 天；急性阶段：尾矿日 - TD 和 1 天后 - DA；慢性阶段：灾难后 3 个月和 1 年）前后采集了样品。我们的结果表明，灾难发生后，金属（类）浓度随时间显著增加，其在水中的化学分配也发生了变化。在急性阶段，总（未过滤）水中观察到 35.2mg Fe L 和 14.4mg Al L，而水相中 Al、As、Cd、Cr、Cu、Fe、Mn、Ni、Pb、Se 和 Zn 的浓度均超过巴西和国际水质安全水平。急性阶段中 Al、Fe 和 Pb 的分配系数 log（K）的降低可能与尾矿中的高胶体含量有关。在慢性阶段，我们继续观察到 Al、Ba、Cd、Cr、Cu、Fe、V 和 Zn 的高浓度主要存在于颗粒态中。此外，多塞河河口以前就受到 As、Ba、Cr、Cu、Mn、Ni 和 Pb 的污染，随着尾矿的释放，沉积物中的这些金属（类）含量进一步增加（例如 Cr 增加了 9 倍，从预冲击的 3.61±2.19μg·g 增加到慢性阶段的 32.16±20.94μg·g）。多塞河沉积物和原始尾矿样品在 Al、As、Cd、Cr、Cu、Fe、V 和 Zn 等金属（类）组成方面相似。因此，这些元素可以作为丰当尾矿的地球化学示踪剂，并考虑其他关键参数来定义监测该环境灾难影响的基线。
