Investigation of Bacteria Biostimulation Strategy for Heavy Metal Bioremediation in Wupa Wastewater Treatment Plant, Abuja

Abstract

Heavy metal pollution in water systems disrupts ecosystems and poses serious public health risks. Bioremediation remains the most cost-effective and eco-friendly, relying on naturally occurring microorganisms to degrade or transform toxic contaminants. This study was aimed at stimulating microbial isolates from Wupa Wastewater Treatment Plant (WWWTP) with nutrients to remove heavy metals from effluents obtained. Wastewater samples collected from Wupa WWTP were analyzed for physicochemical parameters, including pH, electrical conductivity, turbidity, temperature, BOD, COD, TSS, TDS, and concentrations of zinc (Zn), manganese (Mn), and iron (Fe), using standard methods. Bacteria and fungi were isolated microbiologically, and a nine-day container experiment was conducted with four nutrient setups containing different concentrations of peptone (150 ml, 75 ml) and glucose (9 g, 4.5 g) to enhance microbial degradation capability. Biomass growth was monitored every three days using a UV spectrophotometer. The results revealed that physicochemical parameters of the treated and untreated wastewater exhibit significant differences (p<0.05), except for pH and temperature. All physicochemical parameters showed significant differences (p < 0.05) between treated and untreated wastewater, except pH and temperature. Heavy metal concentrations also differed significantly (p < 0.05), with Mn decreasing from 0.37±0.20 mg/L (untreated) to 0.31±0.10 mg/L (treated), Fe from 1.58±0.2 mg/L to 0.91±0.3 mg/L, and Zn from 0.501±0.10 mg/L to 0.501±0.10 mg/L. Eight bacterial species were isolated. The biostimulated microbial consortium effectively remediated Mn, Fe, and Zn by 66.8%, 60.5%, and 70.2%, respectively. This study demonstrates promising potential for heavy metal removal from wastewater treatment plants and industrial effluents.