The Black and Nhue-Day River sub-basins near Hanoi, Vietnam, are crucial aquatic ecosystems that are suffering from severe pollution stemming from industrial, domestic, and agricultural sources, which pose risks to environmental and public health. We assessed water genotoxicity at four locations along a gradient of urbanization in Hanoi and its peripheral regions: a fish farm at Hoa Binh reservoir (HB), a peri-urban fish farm...