Abstract

Globally, the influence of mining activities on the quality of drinking waters have been reported by several researchers. Long-term exposure to potentially toxic elements (PTEs) (e.g. As, Cd, Co, Cu, Fe, Mn, Ni, Pb, Se and Zn) can cause serious health hazards to consumers of polluted water. In the current study, twenty groundwater samples from Ameka mine area were analyzed for PTEs pollution and the associated human health risks. The concentrations of As, Cd, Ni, Pb Co, and Se were found to be above their standard limits in majority of the samples. Index methods such as heavy metal evaluation index, heavy metal pollution index and contamination degree confirmed that majority of the samples are loaded with PTEs. Similarly, synthetic pollution index further revealed that all the samples are extremely polluted and thus very unsuitable for human consumption. The health risk assessment model proposed by US-EPA was applied in assessing the associated health risks of PTEs in the groundwater resources. Non-carcinogenic health risk assessment predicted that 100% of the samples have hazard index values > 4, indicating an extremely high chronic health risk for adults and children. Similarly, carcinogenic risk assessment showed that all the samples pose high cancer risk to both populations due to As, Ni and Cd pollution. However, all the samples pose low cancer risk due to Pb enrichment. Multivariate statistical analyses (such as Pearson’s correlation matrix and principal component extractions) indicated that mining activities and rock-water interactions (weathering) are the responsible sources for the elemental pollution of the groundwater system. Before consumption, adequate treatment is recommended for the polluted waters.

摘要

在全球范围内，一些研究人员报告了采矿活动对饮用水质量的影响。长期接触潜在有毒元素 (PTE)（例如 As、Cd、Co、Cu、Fe、Mn、Ni、Pb、Se 和 Zn）会对受污染水的消费者造成严重的健康危害。在当前的研究中，对 Ameka 矿区的 20 个地下水样本进行了 PTE 污染和相关人类健康风险分析。大多数样品中 As、Cd、Ni、Pb Co 和 Se 的浓度均高于标准限值。重金属评价指数、重金属污染指数、污染度等指标方法证实大部分样品均载有PTEs。相似地，综合污染指数进一步显示，所有样品都被严重污染，因此非常不适合人类食用。应用US-EPA提出的健康风险评估模型评估地下水资源中PTEs的相关健康风险。非致癌健康风险评估预测100%样本的危害指数值>4，表明对成人和儿童的慢性健康风险极高。同样，致癌风险评估表明，由于 As、Ni 和 Cd 污染，所有样本都对两个人群构成了高癌症风险。然而，由于 Pb 富集，所有样品都具有较低的癌症风险。多变量统计分析（如皮尔逊相关矩阵和主成分提取）表明，采矿活动和岩水相互作用（风化）是地下水系统元素污染的罪魁祸首。食用前，建议对受污染的水进行充分处理。