Heavy metals distribution in sediments along the Killindini and Makupa creeks, Kenya

Abstract

Makupa creek is connected to the Indian Ocean via the Killindini creek; the study deals with the distribution of heavy metals in the Makupa and Killindini creeks. Concentrations of Cu, Cd, Fe and Zn, in sediments at the inner sections of the creeks were high compared to those measured at Likoni (ocean). Considering trace metal levels at the inner sections relative to Likoni the ratios obtained, were Cd 7:1, Cu 13:1, Fe 5:1 and Zn 21:1. The results obtained point at Makupa creek as the main source of heavy metals into the creek system, however iron behaved differently, it was significantly higher at the Killindini Habour P<0.05 (at 95% confidence level). There was a decline in concentrations of, copper and zinc from the inner stations to the frontwater zone at Makupa creek. Spatial variations of cadmium were not significant between inner and frontwater zones of the Makupa creek P>0.05 (at 95% confidence level), and also between Makupa and Harbour. There was however a significant difference P<0.05 (at 95% confidence level) between Likoni and Makupa.