Evaluation of heavy metals level of soil in old Panteka market area of Kaduna, Nigeria

Abstract

The aim of this research is to determine the level and distribution of Cu, Cd, Cr, Pb and Ni from soils samples within the vicinities of Old Panteka market of Kaduna state, Nigeria. The design of this study is to compare the soil heavy metal concentrations with regulatory standard values permitted by the Nigerian environmental guideline as well as international standards and also subject the data to descriptive analysis to determine the correlation between the heavy metals and some physicochemical parameter. Forty-four soil samples at 0 to 5cm and 5 to 10 cm depths from ten (10) sample locations and one control sample was collected on the same day at Old Panteka market of Kaduna, Nigeria. The total concentrations of Cu, Cr, Cd, Pb and Ni were determined using Atomic Absorption spectrophotometer. Cation exchange capacity (CEC), pH, electrical conductivity (EC) and particle size distribution of the soil samples were also determined. The mean concentrations of heavy metal of the metal/welding soils at 0-5 cm were; Cr: 0.00 - 113.95 mg/kg, Cu: 15.68 – 2550.53 mg/kg, Cd: 1.33 - 6.30 mg/kg, Pb: 116.30 - 1220.45 mg/kg, Ni: 9.35 - 145.05 mg/kg, while at 5-10 cm, the ranges were; Cr: 0.10 - 161.73 mg/kg, Cu: 16.00 - 3446.43 mg/kg, Cd: 1.28 - 11.23 mg/kg, Pb: 95.85 - 958.40 mg/kg, Ni: 14.18 - 170.78 mg/kg. The concentrations of the studied metals in the soils from the experimental sites were higher than the corresponding values from the control site at both depths with a general increase in metal concentration with soil depth in most of the sites. Results of the heavy metals in the soils of the experimental sites indicated that the metals were mostly above the European commission (1986) recommended limits for these metals in soil with few exceptions.

Keywords: Soil; heavy metals; Correlation; Atomic Absorption spectrophotometer; Cation exchange capacity (CEC); pH; electrical conductivity (EC); Particle size