Iodine Isotopes (¹²⁹I and ¹²⁷I) in the Baltic Proper, Kattegat, and Skagerrak Basins

Abstract

Radioactive anthropogenic pollution has raised concerns about the present and future environmental status of the semienclosed Baltic Sea. We here study the distribution and inventory of the anthropogenic radioactive (129)I in water depth profiles collected from 16 sites in August 2006 and 19 sites in April 2007 in the Baltic Proper and related Kattegat and Skagerrak basins. The results reveal considerable differences of (129)I concentration in terms of spatial and temporal variability and expose relatively high concentrations in the deep waters. Variability in the concentration of (127)I, stable natural isotope of iodine, seems to follow changes in the seawater salinity, but in oxygen-poor bottom waters sediment diagenetic release may contribute to the concentration of both isotopes in the water body. Inventory estimates show that (129)I in August 2006 (24.2 ± 15.4 kg) is higher than that in April 2007 (14.4 ± 8.3 kg) within the southern and central Baltic Proper whereas almost a constant load occurs in the Kattegat Basin. Calculated model inventory shows correspondence to empirical data and provides a guideline for future environmental assessment on the impact of (129)I load in the studied region.

129I and its species in the East China Sea: level, distribution, sources and tracing water masses exchange and movement

“…In the North Sea, Baltic Sea, Norwegian Sea and Arctic, 129 I/ 127 I ratios of 10 −8 –10 −6 were reported because of huge amount of 129 I discharged from the European nuclear fuel reprocessing plants (NFRPs)at Sellafield (UK) and La Hague (France) has dispersed with sea current to these area417181920. In the Fukushima offshore water, the 129 I/ 127 I ratios reached to 2.2 × 10 −9 (6.3 × 10 8  atoms/L for 129 I concentration) due to the releases from the Fukushima accident10 (Supplementary Table S4).…”

High iodine adsorption performances under off-gas conditions by bismuth-modified ZnAl-LDH layered double hydroxide

“…5 In addition, to reduce the chances of the physical uptake of rarer radioactive isotopes from the environment, 127 I can be used in large doses. Nevertheless, studies reveal 6,7 that this approach is dangerous in the long term.…”

127I and 129I Species and Transformation in the Baltic Proper, Kattegat, and Skagerrak Basins

“…Data on total iodine isotopes ( 127 I and 129 I) and their species ( 127 I − , 129 I − , 127 IO 3 − , and 129 IO 3 − ) in surface water (above 10 m depth) of the regions studied here were published by Yi et al 18 and Hansen et al, 19 respectively. Iodine analyses of depth profiles presented here (Table S1 of Iodine Isotopes Variability with Depth.…”

“…9 Furthermore some studies have shown that iodide may be supplied to the water body through organic matter decay and diagenetic release from sediment by diffusion process. 18,30,31 For abiotic reduction process, reducing agents such as iron and manganese can promote the removal of oxygen from iodate and the reduction into iodide in anoxic environment. 32 The reduction may happen in deep or surface water depending on environmental conditions and several reactions have been proposed for the iodate reduction process including:…”