Thesis for the Degree of Doctor of Philosophy - DTU Orbit

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127 I - (ppb) 127 IO3 - (ppb) a b 129 I - (10 8 atoms/L) 129 I - / 127 I - (10 -8 ) 129 IO3 - (10 8 atoms/L) c d e f 129 IO3 - / 127 IO3 - (10 -8 ) Fig. 12 Distribution of 127 I - , 127 IO3 - , 129 I - , 129 IO3 - , 129 I - / 127 I - and 129 IO3 - / 127 IO3 - (a-f) in the bottom water of Kattegat and Baltic Sea for samples collected in April 2007. 48
Although the oxygen concentration decreases with increasing depth in the Baltic Sea and at some locations reaches anoxic conditions (unpublished data), an opposite trend occurs for the concentration of 129 IO3 - and 127 IO3 - (Figs. 9 and 10 and Paper III). A possible explanation for the high concentration of 129 IO3 - in oxygen depleted deep water of the Baltic Sea may be the transport of iodate enriched Kattegat water which flows along the bottom of the Baltic Sea and is subsequently transported to the Arkona, Bornholm and Gotland Basins. The enrichment of iodate in anoxic bottom water of the Baltic Sea may however be explained not only by the effect of saline water intrusion. Another source of iodate under such anoxic conditions can be the release of iodine as iodide and iodate from sediments by digenetic processes (Yuita, 1992; Muramatsu et al., 1996). Our results show that the reduction of iodate in the oxygen deficient bottom water of the Baltic proper (Figs. 9 and 10) is a slow process since higher concentrations of iodate (both isotopes) was found in bottom water when comparing with surface and intermediate waters of Baltic Sea for both seasons. The results of this work shown that (i) reduction of iodate and oxidation of iodide in Skagerrak and Kattegat may be a slow process since insignificant change in 129 I and 127 I speciation was found (ii) reduction of iodate to iodide seems to be relative fast process in surface water of the southern Baltic Sea; (iii) although suboxic or anoxic condition occur in some of the Baltic Sea deep waters, the concentration of 129 IO3 - increases with water depth indicating that the reduction of iodate in the anoxic bottom water of Baltic Sea seems to be a slow process. The main mechanism of iodine reduction may thus be biotically driven rather than abiotic. 3.3.2 Spatial and temporal variation of 129 I and 127 I by analysis of archived Fucus Vesiculosus samples (in paper V). Over the past decade, liquid and gaseous release of 129 I from reprocessing facilities such as La Hague (France) and Sellafield (UK), has significantly increased the natural environmental concentrations by several orders of magnitude (Alfimov et al., 2004; Fehn et al., 2007; Aldahan et al., 2007). The relatively long half life of 129 I (15.7 myr) and the long residence time (30 kyr) of iodine in the marine environment as well as continuous releases from nuclear fuel reprocessing facilities make this isotope a suitable oceanographic tracer. Apart from marine tracer aspects we may also gain insight into the important production of volatile iodine species created by marine algae and which are released to the atmosphere. Marine algae play an important role (Leblanc et al., 2006) in the global cycle of iodine in the environment in the sense that they accumulate seawater iodine at high concentration levels and have the ability to transform a part of it into volatile organic iodine (VOI), such as methyl iodide (CH3I) or diiodomethane (CH2I2; Carpenter et al. 2007) and release them into seawater. From the seawater surface the volatile organic iodine species are released into the atmosphere and are subsequently broken down by photolysis and reactions with ozone (O3) (Jones & Carpenter, 2005; Martino et al. 2006) forming a reactive pool of iodine species which afterwards contribute to the ozone depletion, particle formation and cloud condensation (Küpper et al., 2008; O’Dowd et al., 2002). Despite the significant role of marine algae in the iodine cycle in the environment, 49
Page 1 and 2: Chemical Speciation Analysis and En
Page 3 and 4: Thesis for the Degree of Doctor of
Page 5 and 6: Abstract This thesis deals with che
Page 7 and 8: environment since they reflect the
Page 9 and 10: organiske jodformer. Adsorption af
Page 11 and 12: None of this would have been possib
Page 13 and 14: Abbreviations and acronyms b+ - pos
Page 15 and 16: 3.1 Analytical Development………
Page 17 and 18: Table 1 Some properties of iodine P
Page 19 and 20: In soils/sediments iodine occurs as
Page 21 and 22: Table 2 Nuclear properties of iodin
Page 23 and 24: Liquid scintillation counting (LSC)
Page 25 and 26: The bioavailability of radioactive
Page 27 and 28: data (Englund et al., 2010; Hou et
Page 29 and 30: 2. Analytical procedures used in th
Page 31 and 32: 2.3 Quantification of total iodine
Page 33 and 34: Fig. 5 Quantification of total iodi
Page 35 and 36: iodate were measured by counting 12
Page 37 and 38: Fig. 6 Sequential extraction proced
Page 39 and 40: a Fig. 8 Calibration curve for (a)
Page 41 and 42: experiment was subjected to combust
Page 43 and 44: Table 7 Adsorption of iodine specie
Page 45 and 46: numbers 11-14), which is about the
Page 47 and 48: marine environment from nuclear fue
Page 49: 127 I - (ppb) 127 IO3 - (ppb) a b 1
Page 53 and 54: 129 I TBq 2,00E+00 1,80E+00 1,60E+0
Page 55 and 56: • Adsorption of iodine species on
Page 57 and 58: Reference Aldahan A, Kekli A, Possn
Page 59 and 60: Fuge R& Johnson C. 1986. The geoche
Page 61 and 62: Lo´pez-Gutie´rrez JM, Garcı ´a-
Page 63 and 64: Shinohara K. 2004. Measurement and
Page 65 and 66: http://www.irsn.fr/EN/news/Document
Page 67 and 68: Review Analytica Chimica Acta 632 (
Page 69 and 70: Table 1 Nuclear properties and prod
Page 71 and 72: Fig. 2. Liquid discharges of 129 I
Page 73 and 74: Fig. 5. Schematic diagram and pictu
Page 75 and 76: 129 I in iodide and iodate is then
Page 77 and 78: Fig. 8. Diagram of air sampler for
Page 79 and 80: Fig. 10. Iodine L3-edge (a) and K-e
Page 81 and 82: analysis of 129 I in water sample a
Page 83 and 84: Yi P, Aldahan A, Hansen V, Possnert
Page 85 and 86: FIGURE 1. Sampling sites (the red s
Page 87 and 88: FIGURE 3. Horizontal distribution o
Page 89 and 90: FIGURE 5. Time series data of 129 I
Page 91 and 92: Environmental Science & Technology
Page 93 and 94: prepared using KI and KIO3. No diff
Page 95 and 96: of their contribution to the Baltic
Page 97 and 98: Fig. S-1 Sampling sites (the red so
Page 99 and 100: Fig. S-3 Vertical distribution of I
Page 101 and 102:
Fig. S-5 Marine discharges function
Page 103 and 104:
Fig.S-7 Relationship between I-129
Page 105 and 106:
Table S-1 Results of I-129 and I-12
Page 107 and 108:
S17
Page 109 and 110:
Paper III Hansen,V., Yi, P., Hou, X
Page 111 and 112:
conversion process between iodide a
Page 113 and 114:
Table 1 Analytical results of 129 I
Page 115 and 116:
August April I-129 iodide ( 10 8 at
Page 117 and 118:
References Aldahan A, Kekli A, Poss
Page 119 and 120:
Partition of iodine ( 129 I and 127
Page 121 and 122:
Norway (Table 1). CTD-casts with ox
Page 123 and 124:
5. Discussion 5.1. Separation of hu
Page 125 and 126:
In the present study 40e60% of 129
Page 127 and 128:
Hutta, M., Gora, R., 2003. Novel st
Page 129 and 130:
Analysis of 129 I and 127 I in arch
Page 131 and 132:
et al., 2002). Due to the fact that
Page 133 and 134:
espectively. The iodine was leached
Page 135 and 136:
salinities in the same area. Apart
Page 137 and 138:
North Sea. 129 I/ 127 I ratios in w
Page 139 and 140:
Table 2 Analytical results of 129-I
Page 141 and 142:
129 I/ 127 I 1,40E-07 1,20E-07 1,00
Page 143 and 144:
References Aldahan A, Englund E, Po
Page 145 and 146:
O’Dowd, C.; Jimenez, J. L.; Bahre
Page 147 and 148:
Iodine ( 129 I and 127 I) speciatio
Page 149 and 150:
water in winter by molecular oxygen
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0.2 M KNO3. The effluent and the wa
Page 153 and 154:
maximum values is at 0.03-0.06×10
Page 155 and 156:
into the English Channel from the L
Page 157 and 158:
References Aldahan A, Kekli A, Poss
Page 160 and 161:
Risø-PhD-81(EN)
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Thesis for the Degree of Doctor of Philosophy - DTU Orbit

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