Investigating the Efficacy of Bacillus Species in Biodegrading Heavy Metal Pollutants in Soil from Mining Site in Osun State

Student: Mariam Folashade Bello (Project, 2025)
Department of Biological Science(s)
Federal Polytechnic, Ede, Osun State


Abstract

This study investigates the efficacy of bacillus species in biodegrading heavy metal pollutants in Soil from Iperindo Mining Site in Osun State. Heavy metal pollution from mining activities poses a significant threat to the environment, leading to soil degradation, groundwater contamination, and bioaccumulation in plants and animals. Conventional remediation techniques, such as excavation and chemical stabilization, are often costly and environmentally disruptive. As a sustainable alternative, microbial-assisted bioremediation has gained attention for its ability to detoxify heavy metals efficiently. This study investigates the efficacy of Bacillus species in biodegrading heavy metal pollutants specifically Iron (Fe), Zinc (Zn), and Copper (Cu) from contaminated soil collected at the Iperindo mining site in Ijesha land, Osun State, Nigeria. Laboratory experiment was conducted to Isolate Bacillus spp from the soil sample collected. This is tagged as Isolated Bacillus. A soil sample were then sterilized in an oven at 180o C for one and half (1½) hour to ensure that all microbes present in the soil are destroyed. ICP-OES, was used to determine the concentration of heavy metals present in the soil at this stage. Some Bacillus spp were gotten from hospital (LAUTECH) and they are tagged clinical Bacillus. The sterilized soil sample were then divided into three equal parts and there was careful introduction of the clinical Bacillus to one part, Isolated Bacillus to the second part and the third part served as control. The results revealed a significant decline in Fe, Zn, and Cu concentrations in the treated soil compared to control samples, confirming the ability of Bacillus spp. to detoxify heavy metals through biosorption, bioaccumulation, enzymatic transformation, and bioprecipitation. Additionally, microbial load analysis demonstrated the resilience of Bacillus spp. in metalcontaminated environments, highlighting their potential for large-scale remediation efforts. However, the efficacy of Bacillus spp. depends on various factors, including soil composition, microbial adaptation, and environmental conditions.

Keywords
investigating efficacy bacillus species biodegrading heavy metal pollutants mining state