Urban inputs of fecal bacteria to the coastal zone of Libreville, Gabon, Central Western Africa

Libreville, the largest city in Gabon, adversely impacts Komo Estuary and Akanda National Park aquatic ecosystems through discharge of domestic industrial waste. Fecal Indicator Bacteria (FIB: Escherichia coli fecal streptococci) were enumerated using culture-based methods water from 40 sites between 2017 2019 including coastal outlets, mangrove channels, open bays littoral rivers. Contamination levels high waters small urban rivers Libreville agglomeration, frequently exceeding international safety guidelines, whereas FIB concentrations decreased downstream main channels. Littoral forest significantly impacted by contamination despite absence settlements watersheds. Protected areas are not effective avoiding contamination, indicating inefficient waste management. Dedicated management policies should be implemented to reduce both sanitary concern global pollution, poorly assessed a context demographic increase tropical zones.