Abstract
Heavy metals are toxic and detrimental environmental pollutants. Their release into the environment could be a major cause of water and soil pollution majorly exacerbated by industrialization. This study was conducted to assess the ability of abattoir effluent to remediate soil contaminated with heavy metals (cadmium and zinc). A synthetic polluted soil was produced where 50g of Cd (NO3)2. XH2O and ZnCl2 XH2O were added to uncontaminated soil. The soil sample was then air-dried for 24 hours at room temperature in the laboratory. A 200g and 300g of abattoir effluent were added to the soil samples and kept in the laboratory for a 3-week remediation period. The effluent was subjected to a microbiology test to isolate and identify bacteria and fungus in the effluent. Bacteria such as Salmonella sp., Escherichia coli, Staphylococcus sp., Shigella sp., Pseudomonas sp., Enterobacter sp., Proteus sp., and Micrococcus sp. and fungi such as Aspergillus niger, Penicillium sp, Trichoderma sp, and Rhizopus sp. were all isolated and characterized from the abattoir effluent. After remediation, the results showed a very significant (P < 0.05) reduction in heavy metal concentrations in the soil samples. Additionally, Sample B (200g Abattoir Effluent) revealed the highest cadmium removal efficiency of 98% while Sample C (300g Abattoir Effluent) recorded 79% removal performance in zinc. Abattoir effluent has the potential of removing heavy metals such as cadmium and zinc from polluted soil with time.

Key words: Bioremediation, Abattoir effluent, Heavy metals