The most recent dam rupture in Brazil released tons of mining tailings into the upper course of the Paraopeba River, affecting this river in an unprecedented way. The present study aimed to evaluate the influence of heavy metals on , an important commercial species in Brazil, four years after the dam colapse. To this end, biomarkers of heavy metals, oxidative stress, and environmental stress were analyzed, and histological analyses of target organs were performed. The results demonstrated critical contamination of fish from the Paraopeba River. Increased expression of Metallothioneins - MTs, Heat Shock Protein - HSP70, and inducible nitric oxide synthase - iNOS, as well as greater rates of histological changes in the liver, spleen, and gonads, were observed in . These findings demonstrate that, despite past contamination, the metals present in mining tailings have significantly increased the contamination of the Paraopeba River basin.

中文翻译：

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重金属污染的新热带河流中Prochilodus costatus的组织病理学及金属硫蛋白、热休克蛋白和诱导型一氧化氮合酶表达的变化


巴西最近的大坝溃决将数吨采矿尾矿释放到帕拉佩巴河上游，对这条河流造成了前所未有的影响。本研究旨在评估大坝溃决四年后重金属对巴西重要商业物种的影响。为此，分析了重金属、氧化应激和环境应激的生物标志物，并对靶器官进行了组织学分析。结果表明帕拉奥佩巴河中的鱼类受到严重污染。在 .这些发现表明，尽管过去存在污染，但采矿尾矿中存在的金属显着增加了帕拉奥佩巴河流域的污染。