Sea dumping of highly radioactive materials has been banned worldwide since the beginning of the 1960s and the ban was extended in 1983 to include low-level radioactive wastes. In theory, the oceans can eventually dilute nearly any radioactive waste to the point of harmlessness. But local releases of high concentrations can be dangerous if picked up by marine life and carried into the food chain.
An international group of 116 scientists and radiation experts concluded in 1993 that nuclear wastes dumped in oceans over the decades apparently pose no global danger. Any potential problem would be a local one and would pose no threat on a global scale. However, local threats from the Russian wastes, which are mainly in the Kara and Barents seas, inside the Arctic Circle, are entirely theoretical.