Determination of selected heavy metals in agricultural soils in Bungoma and Kakamega Counties, Western Kenya

Anthony Masika Pembere; Fredrick Derik Otieno Oduor; David Kinuthia Kariuki; Isaac Jumba

Anthony Masika Pembere Department of Chemistry, University of Nairobi
Fredrick Derik Otieno Oduor Department of Chemistry, University of Nairobi
David Kinuthia Kariuki Department of Chemistry, University of Nairobi
Isaac Jumba Department of Chemistry, University of Nairobi

Keywords: Heavy metals, Soils, Toxicity levels

Abstract

A study was conducted to investigate the level of heavy metals in agricultural soils in Bungoma and Kakamega counties, Western Kenya. Copper (Cu), Lead (Pb), Cadmium (Cd), Chromium (Cr) and Zinc (Zn) were determined during the months of November 2010 (wet season) and February 2011 (dry season). Atomic Absorption Spectrophotometer was used for analysis of the samples after wet digestion and preparation of appropriate calibration standards. 11% of the soils reported to be polluted with lead, while 97% were polluted with cadmium. Soils were found to have optimum to low levels of copper and zinc. A positive correlation of wet and dry seasons was reported.