| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1434-1 | ||||
Resumo:Contamination of drinking water by heavy metals poses a substantial threat to both human health and the sustainability of aquatic ecosystems. This study focuses on the Doce River basin, which experienced an environmental disaster in 2015 due to the rupture of a mining tailings dam, resulting in a substantial release of waste materials. Among the most hazardous heavy metals are arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg), all of which are recognized for their adverse effects on human health and the environment. These elements, when present in excessive amounts, can disrupt the food chain by causing growth abnormalities, reproductive issues, and increased mortality rates.
The process of heavy metal bioaccumulation presents an additional challenge, as these elements cannot be easily eliminated or metabolized by organisms. Consequently, contamination levels tend to rise as the metals move through different trophic levels, a phenomenon known as bioamplification. Given that humans often occupy the apex of the food chain, they are susceptible to accumulating dangerous concentrations of these metals in their tissues, rendering them more prone to diseases.
The Doce River basin disaster serves as a stark reminder of the dire consequences of environmental contamination. The dam breach led to the release of tailings rich in iron, silica, and trace metals, resulting in water pollution and extensive loss of fish and invertebrate populations. Beyond the immediate damage, this pollution has had detrimental effects on the microbial communities within aquatic ecosystems, resulting in shifts in biodiversity and alterations in microbial interactions.
Within this context, the study employs metabarcoding, a high-throughput sequencing technique, to examine microbial diversity based on specific gene sequences. The findings demonstrate the persistent presence of microorganisms associated with heavy metals and iron ore residues in the Doce River basin's waters for a period of three years. This suggests an ongoing impact of contamination on the aquatic microbiota. Through the analysis of co-occurrence networks among microorganisms, a deeper comprehension of the intricate interactions within these ecosystems is attained. Notably, certain key species like Gaiella and Pirellula, which are linked to contaminated environments, are identified. Furthermore, novel microorganisms are discovered, underscoring the significance of exploring microbial diversity in response to contamination.
These findings carry substantial implications for aquatic ecology and the restoration of affected ecosystems. A comprehensive understanding of microbial interactions proves pivotal in gauging environmental health and devising effective mitigation strategies. The insights gained from this study could inform bioremediation efforts, where specific microorganisms are harnessed to reinstate environmental equilibrium. In sum, the peril of heavy metal contamination poses a grave threat to aquatic ecosystems and human well-being. By scrutinizing microbial diversity and interaction networks, this study unveils intricate dynamics within polluted environments. Such insights can steer management and recovery initiatives, ultimately contributing to the preservation of vital ecosystems and the advancement of enduring environmental well-being. Palavras-chave: Biomonitoramento, Microbioma, Microbiologia de água doce, Rio Doce, Redes de Co-ocorrência Agência de fomento:CAPES | |||||