Levels of Cadmium and Lead in Water, Sediments and Selected Fish Species in Mombasa, Kenya

Abstract

Flame absorption spectrophotometry was used to investigate the concentration and distribution of cadmium and lead in water, sediments and selected fish species in Makupa and Tudor creeks in Mombasa, Kenya between May 1997 and March 1998. The results were compared with those obtained in relatively less anthropogenically influenced areas along the Kenyan coast. The mean concentrations for Pb ranged from not detectable (nd) to 0.012 mg/l, 0.2 to 58.0 mg/kg and nd to 59.3 mg/kg in water, sediment and fish samples respectively. Cadmium concentrations in water were generally below detection limits, while in sediment and fish samples, they ranged from nd to 1.0 mg/kg and nd to 3.7 mg/kg respectively. Overall, Pb and Cd concentrations were low in the water column of Makupa and Tudor creeks, with a few incidents of elevated levels in sediments and some fish species, especially during the rainy season. Makupa creek had the higher levels overall. The levels of Pb and Cd in most of the fish species analysed were generally within acceptable limits by FAO standards.