A team of scientists from Berlin analysed water and sediment samples from six water bodies in Berlin and the adjacent federal states of Brandenburg and Mecklenburg-Western Pomerania, as well as the inflow and outflow of a wastewater treatment plant in Berlin. The scientists analysed bacteria found in these samples and detected a higher diversity and load of antibiotic resistance genes in urban samples. The inflow and effluent from the treatment plant were the most heavily contaminated, but resistant bacteria were also found in rural lakes far from urban areas. The study is published in the journal “iScience”.