Munene Emily N, Hashim Nadir O, Ambusso Willis N
Physics Department, Kenyatta University, P.O. Box 43844, Nairobi, Kenya.
MethodsX. 2023 Aug 1;11:102298. doi: 10.1016/j.mex.2023.102298. eCollection 2023 Dec.
Heavy metal pollution in surface waters has become a major worldwide issue as people tend to settle where there is readily available source of water like a river. This research evaluates the causes, concentration and associated health risks of heavy metals in River Sosiani as it passes through the town of Eldoret. Seven water samples were collected and analysed for zinc (Zn), copper (Cu) and lead (Pb. The results disclosed that Pb concentrations were estimated to be in the range of 0.06 mg/l to 0.23 mg/l, higher than the permitted limit by WHO of 0.01 mg/l. Cu and Zn concentration levels were below the permissible limits. The chronic daily intake (CDI) indicated that total hazard quotient of non-cancer risk of Pb was above one and the total HI values for children were greatly elevated compared to those of adults in the studied area. This showed a high risk in exposure to Pb. Health human risk was assessed and the incremental life cancer risk (ILCR) values of Pb for children and adults in all sites were found to be negligible with values below 10. However, there is higher cancer and non-cancer risk for children than adults as far as lead metal is concerned. Therefore, measures should be taken in accordance with the standards to prevent potential risk of the river pollution.•Human activities make a significant contribution to heavy metal pollution to surface waters which is a threat to humans.•Water from Sosiani River is not safe for use domestically as far as lead metal levels are concerned.•The results of this study can be used by decision makers to develop measures which can improve the quality of water in the river catchment.
由于人们倾向于在有河流等容易获取水源的地方定居，地表水中的重金属污染已成为一个全球性的重大问题。本研究评估了索西亚尼河流经埃尔多雷特镇时重金属的来源、浓度及相关健康风险。采集了七个水样，分析其中锌（Zn）、铜（Cu）和铅（Pb）的含量。结果显示，铅浓度估计在0.06毫克/升至0.23毫克/升之间，高于世界卫生组织规定的0.01毫克/升的限值。铜和锌的浓度水平低于允许限值。慢性日摄入量（CDI）表明，铅的非致癌风险总危害商高于1，且研究区域内儿童的总危害指数值相比成人大幅升高。这表明铅暴露风险很高。评估了人体健康风险，发现所有采样点儿童和成人的铅增量生命致癌风险（ILCR）值均可忽略不计，低于10。然而，就铅金属而言，儿童面临的癌症和非癌症风险高于成人。因此，应按照标准采取措施，防止河流污染的潜在风险。
•人类活动对地表水中的重金属污染有重大影响，这对人类构成威胁。
•就铅金属含量而言，索西亚尼河的水用于家庭使用不安全。
•本研究结果可供决策者用于制定改善河流集水区水质的措施。
