Case studies of assessment of human health risks after the dam failures of the Córrego do Feijão Mine and Fundão in Brazil

In recent years, there has been an increase in environmental catastrophes involving mining dam failures. This study assessed the potential risks of iron ore tailings in riparian soils to human health after the worst dam collapses recorded in Brazil: from Córrego do Feijão Mine-CFM and Fundão. Chemical monitoring data from the three-year time interval since the collapses were used to estimate human risk indexes for trace elements such as arsenic, cadmium, chromium, mercury, nickel, lead, and zinc. In both case studies, the adult group indicated a propensity for the development of non-carcinogenic diseases through ingestion, inhalation and dermal pathways for all contaminated areas. Overall, children showed an exacerbated sensitivity to possible cancerous and non-cancerous effects, especially in the areas surrounding the dams and in Barra Longa, São José do Goiabal, Córrego Novo, Veneza, Periquito, Governador Valadares, Tumiritinga, Conselheiro Pena, Honório Fraga and Linhares (from the Fundão dam) and in all study areas from the CFM dam. These assessments demonstrate that in regions with mining activities, the cumulative effects of trace elements over time are harmful and expected. Therefore, there is a need for greater supervision by competent government bodies of conservation practices that enable environmental recovery or mitigation of their impacts, ensuring appropriate health and well-being conditions for local residents and workers.

近年来，涉及矿山尾矿坝溃决的环境灾害事件呈上升趋势。本次研究针对巴西有记录以来最严重的两起尾矿坝溃决事件——费焦河（Córrego do Feijão）矿山（CFM）溃坝与丰多（Fundão）坝溃坝——对河岸土壤（riparian soils）中的铁矿石尾矿（iron ore tailings）对人体健康的潜在风险展开评估。研究利用溃决事件发生后三年间隔内的化学监测数据，对砷、镉、铬、汞、镍、铅、锌等微量元素（trace elements）的人体健康风险指数进行估算。在两个案例研究的所有受污染区域中，成人群体均显示出通过摄入（ingestion）、吸入（inhalation）与皮肤接触（dermal pathways）三种途径罹患非致癌性疾病的风险倾向。总体而言，儿童对潜在致癌与非致癌健康影响的敏感性显著升高，尤其是在尾矿坝周边区域，以及丰多坝溃坝涉及的巴拉隆加（Barra Longa）、圣若泽杜戈亚巴尔（São José do Goiabal）、新科雷古（Córrego Novo）、威尼斯（Veneza）、佩里基托（Periquito）、瓦拉达雷斯州长市（Governador Valadares）、图米里廷加（Tumiritinga）、康塞柳佩纳（Conselheiro Pena）、奥诺里奥弗拉加（Honório Fraga）和林哈雷斯（Linhares），以及CFM坝溃坝涉及的所有研究区域。上述评估表明，在存在采矿活动的区域，微量元素随时间累积的健康影响具有危害性且可预见。因此，主管政府部门需加强对环保修复实践的监管，以推动环境恢复或减轻污染影响，保障当地居民与从业者的健康与福祉。