Evaluation of the Physicochemical Quality of Industrial Effluents in the City of Moundou in Southern Chad

Abstract

A substantial proportion of environmental waste arises from industrial activities, much of which comprises hazardous and toxic substances. Untreated industrial effluents have consistently been associated with adverse impacts on both the environment and human health. This study focused on the qualitative assessment of industrial effluents from the city of Moundou discharged into the Logone River. The objective was to determine the physicochemical quality of effluents from Cotontchad, the central slaughterhouse, and Brasseries du Tchad (BDT) and their impact on the Logone River. The pH, temperature, and electrical conductivity were measured in situ. Physicochemical parameters such as COD, BOD5, NO3-, PO43-, SO42-, and heavy metals (Cu, Cd, Pb, Zn, Cr, Fe) were analyzed using spectrophotometric methods. The results are compared with the World Health Organization (WHO) discharge standards. Most of the parameters determined exceed the discharge standards: pH (12.6), electrical conductivity (4270μS/cm), organic matter: COD (1200 mg/L), SO4 (1280 mg/L), PO4 (4460 mg/L), NO3 (63.6 mg/L), Fe (63.34 mg/L), Zn (13.27 mg/L), Pb (4.0 mg/L), Cu (25.34 mg/L), Cd (31.78 mg/L), Cr (5.9 mg/L), Ni (39.5 mg/L). The results obtained revealed a high organic and inorganic load from the discharges of these industries. This shows that industrial effluents from the city of Moundou contribute to the pollution of the Logone River. The industrial effluents received by the Logone River are characterized by significant pollution, which is due to the use of chemicals by manufacturers in the production and manufacturing stages. Finally, based on the results we have found, we propose some solutions on how to eliminate industrial effluents.