POLLUTION BY TRACE METALS OF THE SURFACE WATER OF BONOUA AREA IN HIGH WATER TIME (SOUTHEAST OF IVORY COAST)

The populations of some localities of Bonoua region that no longer have village water works for reasons of mechanical breakdowns use surface water for food. But these waters are confronted with anthropogenic pollution from agricultural activities, to discharges of industrial and domestic wastewater. Indeed, these activities generate magnitudes of amounts of polluting substances whose metallic trace elements (ETM) that negatively affect water quality and subsequently human health. This study aims to assess the level of pollution by trace metals (Cd, Mn, Pb, Cu, Al, Fe and Zn) in times of high water surface water of Bonoua Region to estimate risk sanitation to which people are exposed. To get there, 14 water samples were taken and analyzed by emission spectrometry with Inductively Coupled Plasma (ICP). The data obtained are compared with the WHO standard values for drinking water. The results show that the lead concentrations below the detection limit of the measuring apparatus. The average concentrations of Copper, Zinc and Aluminium conform to WHO drinking water standards. The average concentrations of Cd, Mn and Fe were respectively 15 µg/L, 236 µg/L and 809 µg/L. They are much higher than WHO standards. The assessment of health risks associated with the presence of these ETM in waters show that only Cd and Fe at risk of poisoning in the population and especially among children. This study shows that the surface water of the Bonoua region are under the influence of anthropogenic activities which pose health risks for people, particularly for children.