Assessment of the Level of Heavy Metal Contamination of the Soil in the Bobo-dioulasso Industrial Zone

Abstract

The expansion of human activities has led to the accumulation of heavy metals in various ecosystem compartments. Contamination of soils with these heavy metals poses a significant public health risk because of the various pathologies they can cause. This assessment took into account the levels of heavy metals (As, Cd, Cr, Cu, Ni, Pb and Zn) and some pollution indicators such as the contamination factor (FC), the potential risk of heavy metals (Er), the ecological risk index of heavy metals (IR_ML), the pollution index (IP) and the degree of contamination (Cdeg). A systematic square mesh grid was used to collect 121 soil samples from the three areas occupation of the industrial zone. These samples were analyzed for heavy metal contents. The results show a wide variation in metal concentrations and land use patterns in the industrial zone (P<0.001). Zinc is the metal with the highest concentration in all three zones. Analysis of contamination factors indicated high contamination of As and Cd and high potential for risk of the same elements for all soils at the study site. Ecological risk on living organisms growing in soils is very high (above 300) regardless of the area. The pollution index is higher than 1 (1.09) in the landfill area. Therefore, the soils at the study site can be considered as soils with poor quality in terms of heavy metal content.