New research from Aarhus University and the University of Copenhagen reveals that despite global mercury emission reductions, Arctic wildlife continues to experience increased mercury concentrations. Analysis of over 700 samples, including polar bears and seals, shows ocean currents transporting legacy mercury pollution into the Arctic. The long residence time of mercury in oceans, over 300 years, contrasts with its atmospheric lifespan, explaining persistent contamination. These findings in Nature Communications underscore a prolonged environmental threat to Arctic ecosystems and health, indicating that regulatory measures' benefits will appear only over centuries.