Red de Biología Evolutiva, Instituto de Ecología, A.C., Xalapa, Veracruz, Mexico.
Facultad de Ciencias de la Vida, Universidad Regional Amazónica Ikiam, Tena, Napo, Ecuador.
Chemosphere. 2023 Oct;339:139700. doi: 10.1016/j.chemosphere.2023.139700. Epub 2023 Jul 31.
Metal contamination associated with mining activities has been considered one of the main environmental pollution problems in the Amazon region. Understanding the levels of metal contamination from mining activities requires a good understanding of background metal concentrations, which may vary notably according to the geology/lithology characteristics of the region, soil type, and predominant biogeochemical processes. This review assessed 50 papers and reports published between 1989 and 2020 describing environmental concentrations of different metals and metalloids (As, Hg, Mn, Fe, Cd, Cu, Cr, Pb, Ni, and Zn) in water and sediments of mining and non-mining areas in five geographic regions of the Amazon basin. Metal enrichment caused by mining activities was calculated and exposure concentrations were compared with sediment and water quality standards set for the protection of aquatic life. Significant enrichments of Cd, Cu, Cr, Fe, Hg, Mn, Ni and Zn were observed in mining areas in both sediment and water. Regarding background levels in the different geographic regions, the highest prevalence of metal enrichment (i.e., concentrations 10 to 100-fold higher than mean background values) in sediment samples was found for Fe (100% of samples), Ni (90%), and Mn (69%). For water, high prevalence of metal enrichment occurred for Zn, Mn, and Fe (100% of samples), and for Hg (86%). Hg, Fe, Pb, Cu, Cd, Ni and Zn exceeded water and/or sediment quality standards in a significant number of samples in the proximity of mining areas. This study indicates that mining activities significantly contribute to water and sediment contamination across the Amazon basin, posing hazards for freshwater ecosystems and potentially having human health implications.
采矿活动带来的金属污染被认为是亚马逊地区主要的环境污染问题之一。要了解采矿活动带来的金属污染水平，需要充分了解背景金属浓度，而背景金属浓度可能因地区地质/岩性特征、土壤类型和主要的生物地球化学过程而显著不同。本综述评估了 50 篇发表于 1989 年至 2020 年间的论文和报告，这些文献描述了亚马逊流域五个地理区域的采矿和非采矿区的水和沉积物中不同金属和类金属（砷、汞、锰、铁、镉、铜、铬、铅、镍和锌）的环境浓度。计算了采矿活动引起的金属富集，并将暴露浓度与为保护水生生物而制定的沉积物和水质标准进行了比较。在采矿区的沉积物和水中，均观察到 Cd、Cu、Cr、Fe、Hg、Mn、Ni 和 Zn 的富集。在不同地理区域的背景水平方面，在沉积物样本中，Fe（100%的样本）、Ni（90%）和 Mn（69%）的金属富集程度最高（即浓度比背景值高出 10 到 100 倍）。在水中，Zn、Mn 和 Fe（100%的样本）以及 Hg（86%）的金属富集程度较高。在采矿区附近的大量样本中，Hg、Fe、Pb、Cu、Cd、Ni 和 Zn 超过了水和/或沉积物质量标准。本研究表明，采矿活动大大加剧了亚马逊流域的水和沉积物污染，对淡水生态系统构成了危害，并可能对人类健康产生影响。
