Millions of kilometres of rivers around the world are carrying antibiotic pollution at levels high enough to promote drug resistance and harm aquatic life, a McGill University-led study warns. Published in PNAS Nexus, the study is the first to estimate the scale of global river contamination from human antibiotics use. Researchers calculated that about 8,500 tonnes of antibiotics – nearly one-third of what people consume annually – end up in river systems around the world each year even after in many cases passing through wastewater systems. … The research team used a global model validated by field data from nearly 900 river locations. They found that amoxicillin, the world’s most-used antibiotic, is the most likely to be present at risky levels.