Characterization of Chemical Pollution in the Agbado River Basin in Central Benin
I. Vissoh Roch
Chaire Internationale de Physique Mathématique et Applications, CIPMA CHAIRE-UNESCO, FAST, UAC, Rép. du Bénin.
F. Avahounlin Ringo *
Chaire Internationale de Physique Mathématique et Applications, CIPMA CHAIRE-UNESCO, FAST, UAC, Rép. du Bénin and Ecole Normale Supérieure, ENS, UNSTIM, Rép. du Bénin.
Tomètin A. Lyde
Laboratoire Kaba de Recherche en Chimie et Applications, LaKReCa, UNSTIM, Rép. du Bénin.
Koudérin A. Lucie
Chaire Internationale de Physique Mathématique et Applications, CIPMA CHAIRE-UNESCO, FAST, UAC, Rép. du Bénin.
L. Sintondji
Université d’Abomey, Calavi, UAC, Rép. du Bénin.
Icoutchika Brunelle
Université d’Abomey, Calavi, UAC, Rép. du Bénin.
*Author to whom correspondence should be addressed.
Abstract
The basin of the Agbado River is located across the hills department, between 7°27' and 8°46' north latitude and between 1°39' and 2°44' east longitude. In case to characterize the mineral elements that degrade water quality and to analyze the state of chemical pollution of the waters of the Agbado River, by the characterization of chemical pollution in the Agbado river basin we randomly sampled eight (08) sites throughout along the river. Volumetric and titrimetric methods were used to determine the various physico-chemical parameters in water and sediments. The organic pollution index method was used to assess the water quality of the Agbado River. The results of the physicochemical water analysis reflect the pH variations in the water samples. The pH values do not correspond to the standard accepted by the WHO. The pH values obtained are between 6.01 and 6.69; values below the WHO standard (7-9). The electrical conductivity obtained are between 53.8 and 248 µS/cm. In accordance with the recommendations of the WHO for drinking water (conductivity < 2000µS/cm), translates that the waters analyzed are of low mineralization and therefore tolerable. Regarding major and minor ions only phosphorus, ammoniacal, nitric, sodium, iron, calcium, magnesium contents that do not meet the standard set by the WHO. The results from the determination of the Organic Pollution Index indicate that organic pollution is moderate on all eight (08) sampling sites.
Keywords: Agbado River, chemical pollution, physicochemical parameter, sampling sites, organic pollution index