该研究分析了有毒金属Awetu流域河流的污染水平和生态风险评估。总共收集了20个水和20个沉积物样品,并分析了砷(As)的有毒金属,镉(Cd),铬(Cr),铜(Cu),汞(Hg),锰(Mn),镍(Ni),铅(Pb),锡(Sn),和锌(Zn)。根据沉积物质量指南(SQG)的范围,沉积物样品显示出严重的污染水平。水样显示出高等级的污染因子和有毒金属的潜在生态风险因子。通过内梅罗污染指数评估了采样点有毒金属的协同作用,潜在生态风险指数和修正的污染程度,发现有相似的结果。发现Dololo流(D1,D2,D3和D4)和Kito(K1,K2和K3)处于“有毒”污染和“严重”生态风险。Cd,Mn,Ni,Pb,和Sn贡献了最高的生态风险。多洛河中的有毒金属污染归因于沿河岸进行各种人为活动的机构,包括传统的金属电镀,车库,实验室废水,粗放型农业,洗车,不负责任的废物处理,和城市人口增长。结果表明,Awetu流域河流受到有毒金属的严重污染。因此,未来的污染控制和管理计划应加强对这些人为活动中废物排放的严格监管。
The study analyzed the contamination level and ecological risk assessment of toxic metals Awetu watershed streams. A total of 20 water and 20 sediment samples were collected and analyzed for the toxic metals of Arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), tin (Sn), and zinc (Zn). Sediment samples showed severe contamination levels based on ranges in sediment quality guidelines (SQGs). Water samples showed high grades of contamination factor and potential ecological risk factor by toxic metals. The synergistic effects of toxic metals in the sampling sites were evaluated by Nemerow pollution index, potential ecological risk index and modified degree of contamination and were found to have similar results. Dololo stream (D1, D2, D3, and D4) and Kito (K1, K2, and K3) were found at \'toxic\' contamination and \'severe\' ecological risk. Cd, Mn, Ni, Pb, and Sn contributed to the highest ecological risk. Toxic metal contamination in Dololo stream is attributed to institutions carrying out various anthropogenic activities along the stream bank, including traditional metal plating, garages, laboratory effluents, extensive agriculture, carwash, irresponsible waste disposal, and urban population growth. The result shows Awetu watershed streams are seriously contaminated by toxic metals. Therefore, future pollution control and management plans should accentuate the strict regulation of discharge of wastes from these anthropogenic activities.