Heavy metal pollution in suburban topsoil of Nyeri, Kapsabet, Voi, Ngong and Juja towns, in Kenya

Abstract

The increasing industrialization and agricultural developments in suburban areas of Kenya, has increased the threat of heavy metal contamination in soil. Until now, there are limited studies evaluating metal pollution in suburban towns. This study, therefore, investigated the concentration, distribution and environmental risk of lead (Pb), chromium (Cr), copper (Cu), nickel (Ni), zinc (Zn), mercury (Hg), arsenic (As) and cadmium (Cd) in five townships. Heavy metal source apportionment was examined using principal component analysis and validated using cluster analysis. The relationship between heavy metals was analyzed using Pearson's correlation test and the ecological risk index calculated to determine the degree of contamination. The concentrations of heavy metals were 1.