Contaminación microbiana en el río Pachanlica: impacto, percepción y soluciones ambientales

Introduction: Microbiological contamination of freshwater bodies constitutes an environmental and public health problem, particularly in areas influenced by agroindustrial activities and wastewater discharges. Objective: To evaluate the presence of Escherichia coli and Salmonella spp. in the Pachanlica River, Ecuador, during the dry and rainy seasons of 2023, and to analyze their impact on water quality and community perception. Methods: In situ physicochemical measurements and microbiological analyses were conducted at fourteen sampling points along the river. Fecal coliforms were determined using the Most Probable Number (MPN) method, complemented by confirmatory biochemical tests for Salmonella spp. Additionally, a structured survey was applied to different population sectors to assess environmental perceptions. Results: Fecal coliform concentrations exceeding 2000 MPN/100 mL were recorded during the rainy season in areas with high agroindustrial activity, surpassing regulatory limits. The presence of Salmonella spp. was 21.43% during the dry season and 28.57% during the rainy season. The population expressed concern about water quality. Conclusions: The Pachanlica River shows significant microbiological contamination, which is greater during the rainy season, highlighting the need to strengthen monitoring, sanitation, and environmental management.