Tillaberi Slaughterhouse Discharges And Their Impact On The Niger River: A Physicochemical And Microbiological Analysis

The main objective of this work was to study the solid and liquid waste discharges of the slaughterhouse of the city of Tillabéri, and their impacts on the Niger River. To do so, the identification and quantification of the solid waste of the slaughterhouse were carried out in the first step, then the physical, chemical, and microbiological characterization of the liquid discharges of the slaughterhouse and of the river water in the second step. The results obtained showed that the slaughterhouse in the urban commune of Tillabéri produced an average of 156.1 ± 41.1 kg of solid waste per day, divided into four groups: 133 kg of stercoral, 19.7 kg of seized organs, 1.9 kg of plastic and 1.4 kg of skin pieces. The average values obtained after physic-chemical and microbiological characterization of the liquid waste are as follows pH (7.08 ± 0.15), Temperature (28.6 ± 0.49), Electrical conductivity (985 ±184.1 µS/cm), COD (12860 ± 3831.8mg/l), BOD (5338 ± 1572.05mg/l), Suspended Solid (835 ± 258.7mg/l) Cl- (81.5 ± 1.3 mg/l), NO3- (0.66 ± 0.97mg/l). The BOD5/COD ratio is about 0.41. After microbiological characterization of these liquid discharges, (3.1.104 cfu) of E. coli, (3.104 cfu) of fecal coliforms, and (6.1.108 cfu) of total coliforms were found. The physicochemical and microbiological characterization of the river water showed that most of the physicochemical parameters comply with the WHO limits, except for BOD5 and COD, which have fairly high average values of (62.5 ± 47.06mg/l) and (200 ± 110.1mg/l) respectively. The E. coli found are of the order of 5.6.104 cfu, however, there are no fecal coliforms in these waters. All these values indicate that the river water is polluted. This pollution would come from the discharges of the slaughterhouse