Radioactivity in polar regions - main sources

The common source of anthropogenic radioactivity of the polar regions has been global fallout from nuclear weapons testing in the atmosphere. The depositions from this source are at a minimum in the polar regions. Nevertheless, polar ecosystems may contain relatively high levels of radioactive contamination. This is true, in particular, for the Arctic regions, which beside global fallout have received significant amounts of radioactivity from a number of other sources. Some of the sources viz discharges from nuclear reprocessing in Western Europe and the Chernobyl accident are well described. Others, such as local fallout from the Novaya Zemlya test site, discharges from nuclear facilities to the Siberian rivers Ob, Yenisey and Lena and dumping of nuclear waste in the Barents and Kara Seas are less well documented, but may contribute significantly to the observed and future contamination of the Arctic. (author)