Speaker
Ms
Mareike Schwinger
(Leibniz Universität Hannover, Germany)
Description
The natural abundance of 129I has been changed through anthropogenic activities, such as nuclear weapon testing, nuclear accidents and reprocessing of nuclear fuel. Mainly as a con-sequence of continuous releases of 129I from the nuclear reprocessing facilities in La Hague (France) and Sellafield (UK), 129I is in a state of disequilibrium in all environmental compart-ments in Western Europe.
It is emitted in gaseous and liquid form, with most of it as liquid waste which flows into the North Sea [1]. From there it is reemitted to and distributed in the atmosphere, and precipitates as wet or dry deposition [2].
In this project we analyse precipitation samples from 10 sampling locations and river water samples from 15 sampling locations all over Germany. The concentrations of 129I and 127I are determined, as well as their isotopic ratio.
Iodine is extracted from the water by ion exchange resin. 127I is analysed using inductively-coupled plasma mass spectrometry (ICP-MS) and the isotopic ratio is determined via accel-erated mass spectrometry (AMS).
Results of the 127I analyses reveal slightly higher concentrations for the river water samples (1.7 to 15.9 ng/g) than for the rain water samples (0.6 to 9.8 ng/g). Concentrations of 129I range between 17 to 2000 fg/kg (rain water) and between 17 to 350 fg/kg (river water), respectively. For the precipitation samples (14∙10-9 to 650∙10-9), as well as for the river water samples (3∙10-9 to 40∙10-9), the 129I/127I ratios are at least 3 orders of magnitude higher than the natural equilibrium isotopic ratio of 1.5∙10-12 [2].
[1] J.M. Gómez-Guzmán et al. (2012) Atmospheric Environment 56, 26-32. [2] R. Michel et al. (2012) Science of the Total Environment 419, 151-169.
Author
Ms
Mareike Schwinger
(Leibniz Universität Hannover, Germany)
Co-authors
Abdelouahed Daraoui
(L)
Beate Riebe
(L)
