School of Agricultural Engineering, University of Campinas, Campinas, Brazil.
Institute of Agrarian Sciences, Federal University of Minas Gerais, Montes Claros, Brazil.
Arch Environ Contam Toxicol. 2019 Nov;77(4):527-536. doi: 10.1007/s00244-019-00666-1. Epub 2019 Sep 7.
Vieira River is the main recipient of domestic and industrial wastewater in the city of Montes Claros, MG, Brazil. Until 2010, domestic sewage was dumped in it without any kind of treatment. Concentrations of arsenic (As), chrome (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) were determined in water and sediment samples in eight locations along the Vieira River during the dry season of 2015. Concentrations of Cu, Ni, and Zn detected in the water at some sites along the Vieira River were superior to the reference limits for toxicity. The concentration of Cu and Ni restricts the use of water for irrigation in some sites of the river. The level of sediment contamination was assessed by five approaches, including contamination factor (CF), pollution load index (PLI), geo-accumulation index (I), cluster analysis (CA), and principal component analysis/factor analysis (PCA/FA). The results showed that Cr and the downstream sampling site nearest to the Wastewater Treatment Plant of the city of Montes Claros had the highest values of PLI, I, and CF, which reinforces the influence of domestic and industrial wastewater discharge in pollution of the Vieira River. In addition, CA and PCA/FA reinforced the assumption that Cr comes from anthropogenic pollution sources.
维埃拉河是巴西米纳斯吉拉斯州蒙特克莱尔市的主要接纳城市生活污水和工业废水的河流。直到 2010 年，未经任何处理的生活污水就被直接排放到河中。2015 年旱季，在维埃拉河的 8 个地点采集了河水和河底沉积物样本，检测了砷（As）、铬（Cr）、铜（Cu）、镍（Ni）、铅（Pb）和锌（Zn）的浓度。在维埃拉河部分地段的河水中，Cu、Ni 和 Zn 的浓度超过了毒性参考限值。Cu 和 Ni 的浓度限制了部分河段河水的灌溉用途。采用污染系数（CF）、污染负荷指数（PLI）、地积累指数（I）、聚类分析（CA）和主成分分析/因子分析（PCA/FA）等 5 种方法评估了底泥的污染程度。结果表明，Cr 和位于城市污水处理厂下游的采样点的 PLI、I 和 CF 值最高，这进一步证实了城市生活污水和工业废水排放对维埃拉河的污染影响。此外，CA 和 PCA/FA 也进一步证实了 Cr 来自人为污染源的假设。
