Aklilu Tesfa, Sahilu Geremew, Ambelu Argaw
Ethiopian Institute of Water Resources, Addis Ababa University, Ethiopia.
Civil and Environmental Engineering, School of Civil and Environmental Engineering, Addis Ababa Institute of Technology, Addis Ababa University, Ethiopia.
Heliyon. 2024 Jan 20;10(3):e24790. doi: 10.1016/j.heliyon.2024.e24790. eCollection 2024 Feb 15.
The Upper Awash sub-basin characterized by urban, industrial, agricultural and population growth, has impacted the quality of its water sources. This study focuses on the assessment of public health risks associated with drinking water sources in the sub-basin. In accordance with WHO guidelines, 120 water samples were collected from 60 water supply schemes in dry and wet seasons located in areas with low and high water pollution risk (WPR). Multi-meter, Photometer, Digital Arsenator, and Microbiological test kit measured the concentration of parameters. The assessment uses methods of hazard identification, exposure and dose-response analysis, and risk characterization, including Hazard Quotient (HQ), Cancer Risk (CR), Hazard Index (HI), and probability of infection. Monte Carlo simulation analyzes non-cancer risks from Nitrite, Nitrate, Chromium, Iron, Fluoride, and Arsenic, and CRs from Chromium and Arsenic, and infection risks from (). As a result, the Hazard Quotient (HQ) of Nitrate was beyond unity (HQ > 1) in the dry season for all groups. HQ of Chromium was HQ > 1 for Women (1.1E+00) and Children (1.4E+00) in the wet season in the high WPR area. Chromium HQ > 1 for children (1.4E+00) in the wet season and Fluoride (HQ > 1) for Children (3.2E+00) in the dry season in the low WPR area. Arsenic CR was above 1 in 10,000 persons for children in the dry season, for all groups, and for women and children in the wet season in the high WPR areas. The CR of chromium ranged from 1 in 1000 persons, which is beyond the limit. Moreover, the Hazard Index (HI) was higher than the unity (HI > 1) for most cases. All infection risks daily and annually exceeded the acceptable risks. Therefore, Public health concerns in the Sub-basin were quantified, and evidences were generated for risk management to undertake source protection through integrated watershed management and appropriate water treatment technologies.
上阿瓦什次流域以城市、工业、农业和人口增长为特征，已经对其水源质量产生了影响。本研究聚焦于评估该次流域饮用水源相关的公共卫生风险。按照世界卫生组织的指导方针，在旱季和雨季从位于水污染风险低和高的地区的60个供水系统中采集了120份水样。多用测量仪、光度计、数字砷测定仪和微生物检测试剂盒测量了各项参数的浓度。评估采用危害识别、暴露和剂量反应分析以及风险表征等方法，包括危害商数（HQ）、癌症风险（CR）、危害指数（HI）和感染概率。蒙特卡洛模拟分析了亚硝酸盐、硝酸盐、铬、铁、氟化物和砷的非癌症风险，铬和砷的癌症风险，以及（）的感染风险。结果显示，在旱季，所有群体的硝酸盐危害商数（HQ）均超过1（HQ > 1）。在高水污染风险地区的雨季，女性（1.1E + 00）和儿童（1.4E + 00）的铬HQ > 1。在低水污染风险地区的雨季，儿童的铬HQ > 1（1.4E + 00），在旱季儿童的氟化物（HQ > 1）为3.2E + 00。在旱季，所有群体以及高水污染风险地区雨季的女性和儿童中，儿童的砷癌症风险每万人中超过1例。铬的癌症风险每千人中为1例，超出了限值。此外，在大多数情况下，危害指数（HI）高于1（HI > 1）。所有感染风险的每日和年度值均超过了可接受风险。因此，对上阿瓦什次流域的公共卫生问题进行了量化，并为风险管理提供了证据，以便通过综合流域管理和适当的水处理技术进行水源保护。
