Increase of 129I in the environment

The long-life fission product 129I is released continuously into the environment by nuclear fuel reprocessing plants. The annual 129I deposition rate has been measured with accelerator mass spectrometry (AMS) in an Alpine ice core covering the years from 1950 to 1980. These measurements show, that even at sites not in the vicinity of reprocessing plants, an increase in 129I can be observed. Today's fall-out of 129I is even larger than the fall-out from nuclear weapons tests in the 1960s. Different sources of anthropogenic 129I and the impact on the natural iodine reservoirs are discussed. The results are compared to calculations with a box transport model