Toxicity Identification Evaluation of Industrial Effluent Causing Biological Oxygen Demand Exceedances

Abstract

Industrial effluents containing complex mixtures of organic and inorganic contaminants frequently contribute to elevated biological oxygen demand levels in receiving water bodies, resulting in oxygen depletion and adverse impacts on aquatic ecosystems. Identification of the specific toxic constituents responsible for biological oxygen demand exceedances is essential for effective wastewater management and regulatory compliance. The present study investigates the application of toxicity identification evaluation techniques for characterizing industrial effluents associated with excessive biological oxygen demand under varying treatment and environmental conditions. The research focuses on evaluating contaminant toxicity, inhibitory effects on biological treatment processes, and identification of major pollutant groups contributing to oxygen demand elevation. Experimental analysis was conducted using fractionation, toxicity screening, physicochemical characterization, and biological assessment methods to examine the influence of organic compounds, heavy metals, ammonia, surfactants, and other industrial contaminants on microbial activity and wastewater biodegradability. Results demonstrate that toxicity identification evaluation effectively differentiates toxic pollutant fractions and identifies critical contaminants responsible for biological oxygen demand exceedances and treatment inhibition. The study further reveals that certain industrial chemicals significantly suppress microbial degradation activity, leading to incomplete organic matter removal and reduced treatment efficiency. Comparative assessment with conventional wastewater monitoring approaches confirms the advantages of toxicity identification evaluation, including improved diagnostic capability, targeted pollution source identification, and enhanced process optimization for industrial wastewater treatment systems.