Heavy metal contamination of soil, and bioaccumulation in Guinea grass (Panicum maximum) around Ikeja Industrial Estate, Lagos, Nigeria

Topsoil and vegetation (Guinea grass, Panicum maximum) samples obtained in the vicinity of an industrial complex (the Ikeja Industrial Estate) in Lagos, Nigeria, were analysed for Cd, Pb, Cu, Zn, Ni, Cr and Mn contents. Levels of the metals in soils and plants around the estate were found to be significantly higher than the background concentrations obtained at remote control sites. Average soil concentrations around the estate were: Cd - 2.9 mg/kg, Pb - 143.2 mg/kg, Cu - 25.6 mg/kg, Zn - 247.4 mg/kg, Ni - 17.0 mg/kg, Cr - 26.6 mg/kg and Mn - 282.9 mg/kg, while average plant concentrations were: Cd - 0.73 mg/kg, Ph - 2.9 mg/kg, Cu - 0.93 mg/kg, Zn - 0.72 mg/kg, Ni - 2.3 mg/kg, Cr - 2.3 mg/kg and Mn - 3.7 mg/kg. Plant samples were collected from the same spots as the soil samples, and there was strong correlation between soil and plant contents of Cd, Pb, Ni and Mn.