Excessive Copper(II) and Zinc(II) Levels in Drinkable Water Sources in Areas Along the Lake Victoria Shorelines in Siaya County, Kenya

摘要

Copper(II) and zinc(II) levels in drinkable water sources in the alluvium areas of the Lake Victoria Basin in Siaya County of Kenya were evaluated to assess the risk posed to resident communities by hydrogeological accumulation of toxic residues in the sedimentary regions of the lake basin. The levels of the metals in water were analyzed by atomic absorption spectroscopy. Metal concentrations ranged from 0.11 to 4.29 mg/L for Cu(II) and 0.03 to 1.62 mg/L for Zn(II), which were both higher than those normally recorded in natural waters. The Cu(II) levels also exceeded WHO guidelines for drinking water in 27 % of the samples. The highest prevalence of excessive Cu(II) was found among dams and open pans (38 %), piped water (33 %) and spring water (25 %). It was estimated that 18.2 % of the resident communities in the current study area are exposed to potentially toxic levels of Cu(II) through their drinking water.