Institute of Environmental Studies, University of Karachi, Karachi, Pakistan.
Environ Monit Assess. 2024 Nov 4;196(12):1152. doi: 10.1007/s10661-024-13346-y.
In the present study, piped water samples from Gulshan-e-Iqbal Town, Karachi, were evaluated for their Health Risk Assessment (HRA) and Water Quality Index (WQI). For this, different physicochemical and microbiological parameters were analyzed, and the results were evaluated according to the guidelines established by the WHO (2011) and the National Standards for Drinking Water Quality (NSDWQ) (2008). With the exception of sulphate, all physicochemical parameters were well within the guideline values. The mean concentrations of the metals in the samples were in the following order: Ca > Mg > Zn > Fe > Pb > Ni > Cr > As. More than 70% of the samples tested for Total Coliform Count (TCC), Total Faecal Coliform Count (TFC), Total Feacal Streptococci (TFS), and Total Aerobic Count (TAC) were feacal contaminated. E. coli was also isolated in almost 84.61% of the tested piped water samples. Results from the WQI revealed that 95.6% of samples had good physico-chemical characteristics, and 26% of the piped water samples had good microbiological quality. The WQI readings of all the samples for metals showed that they were unfit for human consumption. The mean Chronic Daily Intake (CDI) and Hazard Quotient (HQ) values, respectively, were in the following order: Zn > Fe > Pb > Ni > Cr > As, and Pb > As > Ni > Cr > Zn > Fe. All HQ values for As and Pb were greater than 1, and 50% of piped water samples had an HQ value for Ni that was greater than 1, indicating that people may suffer serious health issues as a result. All of the piped water samples except the area of block 13 D (S-5), had HQ values of less than 1 in relation to iron, but Zn HQ values of less than 1 indicated only mild health problems. Discharge of untreated sewage and cross-contamination are all potential sources of contamination that could result in diseases that are harmful to the public's health. Water monitoring and management projects should be implemented in order to improve pipeline infrastructure and reduce sewage leakages.
在本研究中，评估了卡拉奇古勒山城镇的管道水样的健康风险评估（HRA）和水质指数（WQI）。为此，分析了不同的理化和微生物参数，并根据世界卫生组织（2011 年）和国家饮用水质量标准（NSDWQ）（2008 年）制定的准则进行了评估。除硫酸盐外，所有理化参数均在准则值范围内。样本中金属的平均浓度顺序为：Ca > Mg > Zn > Fe > Pb > Ni > Cr > As。超过 70%的总大肠菌群计数（TCC）、总粪大肠菌群计数（TFC）、总粪链球菌计数（TFS）和总需氧计数（TAC）测试样本呈粪便污染。几乎 84.61%的测试管道水样中也分离出大肠杆菌。WQI 的结果表明，95.6%的水样具有良好的理化特性，26%的管道水样具有良好的微生物质量。所有样本的金属 WQI 读数表明它们不适合人类饮用。慢性日摄入量（CDI）和危害系数（HQ）的平均值分别为：Zn > Fe > Pb > Ni > Cr > As，Pb > As > Ni > Cr > Zn > Fe。砷和铅的所有 HQ 值都大于 1，50%的管道水样中镍的 HQ 值大于 1，表明人们可能会因此遭受严重的健康问题。除了 13D 区（S-5）的区域外，所有管道水样的铁 HQ 值都小于 1，但锌 HQ 值小于 1表明只有轻度健康问题。未经处理的污水排放和交叉污染都是潜在的污染源，可能导致对公众健康有害的疾病。应该实施水质监测和管理项目，以改善管道基础设施并减少污水泄漏。
