Analysis of heavy metals in roadside soils and crops along the Obansandjo way in the Accra metropolis

Abstract

This paper discusses the levels of some heavy metals (Ni, Cu, Pb and Zn) in roadside soils and crops along the Obansandjo way in the Accra metropolis of Ghana. Soil and plant samples were collected from three different sites; Kawukudi (K), Ebony (E), and Dzorwulu (D) all along the Obansandjo way in Accra. The samples taken were preserved and later acid digested and analyzed along side control soil and plant samples using standard analytical methods. The following mean levels of Ni, Zn, Cu and Pb on the roadsides were detected: 228.65 ± 102.98, 35.98 ± 18.39, 24.577 ± 9.04 and 18.25 ± 13.05 (all in mg/kg) respectively. The mean level of Ni was above the critical permissible concentration. Ni, Zn, Cu and Pb in the crops were: 3.343 ± 2.0, 6.97 ± 4.5, 1.909 ± 0.71 and 3.515 ± 1.3 (all in mg/kg) respectively. Ni, Pb, Cu and Zn were detected in both soils and crops. The levels of all the metals except Ni were below the phototoxic levels. Keywords: Obansandjo way, heavy metals, roadside soils and plants.