BIOREMEDIATION OF ABATTOIR WASTEWATER USING BACTERIAL CONSORTIUM.

Abattoir wastewater is a significant source of environmental pollution due to its high organic load, toxic heavy metals, and nutrient-rich composition. This study aimed to assess the potential of a bacterial consortium comprising Bacillus subtilis, Pseudomonas aeruginosa, and Micrococcus luteus for the bioremediation of abattoir wastewater. The isolates were identified through morphological, Gram staining, and biochemical tests, confirming their suitability for biodegradation. Physicochemical analysis of the untreated wastewater revealed extreme pollution levels, with elevated BOD (1200 mg/L), COD (2800 mg/L), TSS (850 mg/L), oil and grease (185 mg/L), and heavy metals such as Pb (1.85 mg/L), Cd (0.65 mg/L), and Cr (3.20 mg/L), all exceeding WHO permissible limits. Following treatment with the bacterial consortium, substantial improvements were recorded. COD and BOD were reduced by 92.6% and 84.2%, respectively, while TDS, TSS, ammonia, phosphate, and chloride showed 58–86% reduction. Dissolved oxygen increased from 1.2 to 5.3 mg/L, indicating improved water quality. Heavy metals also declined significantly, with reductions of Cd (74%), Ni (86.8%), Zn (86%), Fe (71%), and Cr (55%). These findings demonstrate the efficiency of the bacterial consortium in reducing both organic and inorganic pollutants in abattoir wastewater. In conclusion, this study highlights microbial bioremediation as a sustainable, eco-friendly approach for abattoir wastewater management, capable of mitigating health risks and environmental hazards associated with abattoir effluents.