Incidence of heavy metals in Kano metropolis drinking water sources
Contamination of Kano metropolis drinking water sources with excessive heavy metals was evaluated using standard laboratory procedures. A total of 72 samples comprising of 24 each of Borehole, Tap and Well water from 8 municipal LGAs (namely; Dala, Fagge, Gwale, Kano municipal, Kumbotso, Nassarawa, Tarauni and Ungogo) were analyzed for the presence of heavy metals (viz; Chromium, Iron, Lead and Zinc). Chromium and Lead concentrations for the samples evaluated (Borehole, Tap and Well) were found to exceed the World Health Organizations (WHO) limits of 0.05 and 0.01mg/l respectively which might be attributed to corrosion of brass fittings of certain submersible pumps and pipes used in borehole and taps specifically. The contamination of well with heavy metals might be due to seepage of sewage into these sources as domestic sewage might be of kitchen and toilet origin heavily accumulated with soaps of heavy metals constituents. Heavy metal contamination with Chromium and Lead calls for serious public health implications for the effects of heavy metals contamination in drinking water.
Keywords: Drinking water, Kano, Chromium, Lead, Iron and Zinc