Distribution and Pollution Assessment of Selected Heavy Metals in Flood-Affected and Unflooded Soils of Jigawa State, Nigeria

Abstract

Soil samples from selected locations affected by flood within three selected local government areas (Auyo, Hadejia and Malam Madori) of Jigawa State, Nigeria were analysed for some trace metals (Cd, Cr, Cu, Ni, Pb and Zn) level. These parameters were compared with established international standard (WHO/FAO). Cu, Ni, Pb and Zn fall within the stipulated standards, while Cd exceeded the standard limit from all the sampling sites (both flooded and the control) and Cr exceeded the limits, except at TST and GSK. the trace metals (Cd,  Cu, Ni, Pb and Zn) were having higher mean concentrations from the control samples than the flooded sampled stations (4.73±0.05mg/kg and 5.13±0.03mg/kg, 12.44±0.14mg/kg and 14.42±0.07mg/kg, 29.92±0.25mg/kg and 30.55±0.16mg/kg, 18.65±0.67mg/kg and 19.62±0.53mg/kg and 26.22±0.20mg/kg and 26.58±0.20 mg/kg) respectively while Chromium was observed to be higher in the flooded sampling sites 90.94±1.35mg/kg and 74.64±0.57mg/kg,. Pollution indices assessed showed that the samples were highly contaminated to extremely contaminated for both flooded and the unflooded sampling sites. The study revealed that not only the flood is a major possible pollution source in the surrounding environment. This underlines the need for appropriate government agencies of the state to initiate possible processes to recover all contamination sources and further reduce the pollution level in the surrounding environment.