Influence of Agricultural Inputs and Urban Waste on the Physicochemical and Metal Profile of Surface Waters in Man, Côte d'Ivoire

Water pollution is a major environmental and public health issue. In the city of Man, located in western Côte d'Ivoire, this problem is exacerbated by the coexistence of intensive agricultural zones and precarious urban neighborhoods, often lacking proper sanitation infrastructure. This study aims to assess the physicochemical quality of surface waters in relation to anthropogenic activities within the municipality of Man. The methodological approach combined field surveys on agricultural practices, in situ measurements of physical parameters, and laboratory analyses of major ions and trace metals. Pollution indices (contamination factor and degree of contamination) were used to characterize the contamination status. The results show elevated concentrations of trace metals such as cadmium (Cd), zinc (Zn), iron (Fe), manganese (Mn), and phosphorus (P), exceeding WHO guideline or aesthetic values. Nitrite pollution, above recommended standards despite low nitrate levels, suggests localized organic contamination from domestic wastewater and leachates from illegal dumpsites. Major cations (Ca²⁺, K⁺, Mg²⁺) also present high concentrations, linked both to anthropogenic inputs (fertilizers) and local lithology. Pollution indices confirm a high level of water contamination across all sampled sites. These findings reveal a concerning degradation of surface water quality in Man and call for urgent, integrated water resource management, including better regulation of agricultural practices, improved waste management, and more sustainable urban planning.