Spatial Distribution of Some Heavy Metals in Sediments from the River Hadejia Catchment, Nigeria

Abstract

Heavy metals concentration levels was determined using Instrumental Nitrogen Activation Analysis (INAA) is possible using Nigeria Research Reactor-1 (NIRR) which is a Miniature Neutron Source Reactor (MNSR). It is specifically used for the Neutron Activation Analysis (NAA) technique. The selection of sediment sample is because, overtime, the chemical elements precipitate on the sediment bed; therefore the sediment sample will indicate the true nature of the chemical elements present in the river system. River Hadejia is a perennial river, though the dry season flow is from the upstream regulated flow from the Tiga and Bagauda dams. The sediment samples were collected using stratified random sampling technique based on change in land use activity. Samples were collected during dry and wet seasons and analyzed in the laboratory. The results obtained show the presence of chemical contaminants Chromium (Cr), Zinc (Zn), and Europium (Eu) in concentrations above the permissible limits in the Hadejia river system. For example, Chromium (Cr) has mean concentration of 432.86 mg/l as against the permissible limit for both WHO, (2011) and NSDWQ, (2007) of 0.05mg/l. Anthropogenic and natural geology of the area are the key determinants of the presence of these chemical elements in the area. It is recommended among others that there is need for routing the actual sources of these contaminants in our river catchment areas.