State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China.
Department of Botany, Abdul Wali Khan University, Mardan, 23200, Pakistan.
Sci Rep. 2023 Nov 22;13(1):20455. doi: 10.1038/s41598-023-40105-9.
Arsenic (As), contamination in drinking groundwater resources is commonly environmental problem in many developing countries including Pakistan, with significant human health risk reports. In order to examine the groundwater quality concerning As contamination, its geochemical behavior along with physicochemical parameters, 42 samples were collected from community tube wells from District Bahawalpur, Punjab, Pakistan. The results showed the concentration of elevated As, its source of mobilization, and associated public health risk. The As concentration detected in groundwater samples varied from 0.12 to 104 µg/L with an average value of 34.7 µg/L. Among 42 groundwater samples, 27 samples were beyond the permitted limit of 10 µg/L recommended by World Health Organization (WHO), for drinking purposes. Statistical analysis result show that the groundwater cations values are in decreasing order such as: Na > Mg > Ca > K, while anions were HCO > SO > Cl > NO. Hydrochemical facies result depict that the groundwater samples of the study area, 14 samples belong to CaHCO type, 5 samples belong to NaCl type, 20 samples belong to Mixed CaMgCl type, and 3 samples belong to CaCl type. It can be accredited due to weathering and recharge mechanism, evaporation processes, and reverse ion exchange. Gibbs diagram shows that rock water interaction controls the hydrochemistry of groundwater resources of the study area. Saturation Index (SI) result indicated the saturation of calcite, dolomite, gypsum, geothite, and hematite mineral due their positive SI values. The principal component analysis (PCA) results possess a total variability of 80.69% signifying the anthropogenic and geogenic source of contamination. The results of the exposure-health-risk-assessment method for measuring As reveal significant potential non-carcinogenic risk (HQ), exceeding the threshold level of (> 1) for children in the study area. Water quality assessment results shows that 24 samples were not suitable for drinking purposes.
砷（As）是许多发展中国家（包括巴基斯坦）地下水资源中常见的环境污染问题，这对人类健康构成了重大风险。为了研究地下水的砷污染情况，包括其地球化学行为以及理化参数，我们从巴基斯坦旁遮普省巴哈瓦尔布尔地区的社区管井中采集了 42 个样本。研究结果表明，砷的浓度、迁移来源以及相关的公共健康风险。在地下水样本中，砷的浓度从 0.12 到 104μg/L 不等，平均值为 34.7μg/L。在所采集的 42 个地下水样本中，有 27 个样本的砷浓度超过了世界卫生组织（WHO）规定的 10μg/L 的饮用水标准。统计分析结果表明，地下水阳离子的浓度顺序为：Na>Mg>Ca>K，而阴离子的浓度顺序为：HCO>SO>Cl>NO。水化学成分分析结果表明，研究区的地下水样本中，有 14 个样本属于 CaHCO3 型，5 个样本属于 NaCl 型，20 个样本属于混合的 CaMgCl 型，还有 3 个样本属于 CaCl 型。这可能是由于风化和补给机制、蒸发过程以及反向离子交换作用造成的。Gibbs 图表明，岩石-水相互作用控制了研究区地下水的水化学特征。饱和度指数（SI）结果表明，由于正的 SI 值，方解石、白云石、石膏、针铁矿和赤铁矿矿物处于饱和状态。主成分分析（PCA）结果表明，总变异系数为 80.69%，这表明了人为和地质因素是污染的主要来源。采用暴露-健康风险评估方法对砷进行测量的结果表明，研究区儿童的非致癌风险（HQ）显著，超过了（>1）的阈值水平。水质评估结果表明，有 24 个样本不适合饮用。
