7th ICOBTE 7th International Conference on the ...

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INTRODUCTION. The use of depleted uranium (DU) anti-tank ammunition by NATO forces to strike Serbian armored troops during the 1999 Kosovo conflict ...
7th ICOBTE

7th International Conference on the Biogeochemistry of Trace Elements Uppsala, Sweden, June 15-19, 2003

CONFERENCE PROCEEDINGS

Editors: George Gobran and Nicholas Lepp Editorial Committee:Domy Adriano, Lars Bergström, Roger Finlay, George Gobran, Alex Iskandar, Nicholas Lepp, Enzo Lombi, Steve McGrath, Tracy Punshon, Magdi Selim, Olle Selinus and Walter Wenzel. Cover photos: Mats Gerentz, SLU Printed by: SLU service/Repro, 2003

ISBN 91-576-6582-6

SP14p - Unusual Trace Elements Including Radionuclides

Uranium Contents and 235U/238U Ratio in Soil and Earthworms near Djakovica (Western Kosovo) after the Kosovo War L.A. Di Lella, F. Nannoni, G. Protano, F. Riccobono Dipartimento di Scienze Ambientali, Sezione di Geochimica Ambientale, University of Siena, Via del Laterino 8, Siena, I-53100, ITALY (E-mail: [email protected]) INTRODUCTION The use of depleted uranium (DU) anti-tank ammunition by NATO forces to strike Serbian armored troops during the 1999 Kosovo conflict raised a great deal of public concern in many countries that sent soldiers to the Balkans. According to information provided by NATO, about 30,000 DU rounds were fired by A-10 antitank aircraft in Spring 1999 in Kosovo. Since each DU shell weighed nearly 300 g, a total of at least 9 tons of depleted uranium were added to the background stock of natural U in the affected areas (see UNEP, 2001 for details). One of the most severely hit targets was a former VJ (Yugoslavian Army) garrison near the town of Djakovica in western Kosovo (Fig. 1a). MATERIAL AND METHODS Soils samples and the earthworms living in them were collected and analyzed by ICP-MS to determine the uranium contents and the 235U/238U ratio. The aim was to evaluate the amount of depleted uranium (DU) added to the natural pool and to assess the repercussions on organisms. Soil samples (0-20 cm) from four sampling sites and 17 earthworms belonging to two species (mostly found in two soil samples) were collected. The sampling sites (Fig. 1b) were situated at various distances from obvious clusters of holes produced by the impact of DU penetrators on a concrete platform covering a large part of the garrison area.

Fig. 1. (a) Location of the town of Djakovica in western Kosovo. (b) Sampling sites of soils and earthworms in the VJ garrison of Djakovica.

RESULTS AND DISCUSSION Tables 1 and 2 report the uranium contents and the 235U/238U ratio found in the soil samples and in the earthworms (on d.w. basis). Rather high uranium values were found in soil collected very close to the impact points. The addition of exotic uranium can easily be inferred from the extremely low 235U/238U

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Proc. 7th Intern. Conf. on the Biogeochem. of Trace Elements; Uppsala ’03

SP14p - Unusual Trace Elements Including Radionuclides

ratio. In contrast, the soil a few meters away from the clusters showed much lower U contents and a 235 238 U/ U ratio near to or coincident with natural value. Table 1. Uranium content and 235U/238U ratio in soils.

Sample

U/238U

(µg/g) 8.350 1.864 1.451 31.472

DKSL/C DKSL/D DKSL/H DKSL/L

Table 2. Uranium content and 235U/238U ratio

Sample DKEW/D1 DKEW/D2 DKEW/D3 DKEW/D4 DKEW/D5 DKEW/D6 DKEW/H1 DKEW/H2 DKEW/H3 DKEW/H4 DKEW/H5 DKEW/H6 DKEW/H7 DKEW/H8 DKEW/P1 DKEW/P2

235

U

Species Allolobophora rosea Allolobophora rosea Allolobophora rosea Nicodrilus caliginosus Nicodrilus caliginosus Nicodrilus caliginosus Allolobophora rosea Allolobophora rosea Allolobophora rosea Nicodrilus caliginosus Nicodrilus caliginosus Nicodrilus caliginosus Nicodrilus caliginosus not classificable Allolobophora rosea Nicodrilus caliginosus

0.002588 0.006444 0.007171 0.002147

in earthworms (on d.w. basis). Class Adult Adult Adult ? Adult Adult Adult Adult Adult Juvenile Subadult Subadult Adult Juvenile Adult Adult

U (µg/g) 0.311 0.275 0.463 2.262 0.168 0.184 0.436 0.445 0.342 0.423 0.296 0.440 0.213 0.907 0.188 0.163

235

U/238U 0.007054 0.006822 0.007265 0.007234 0.007101 0.005911 0.007057 0.007198 0.006818 0.007261 0.007213 0.006966 0.007258 0.007245 0.007211 0.007266

The U levels in individuals of the two earthworm species were quite variable but the 235U/238U ratio measured in these organisms appeared to be independent of both the soil U contents and the absolute U levels in the earthworms. These findings are also discussed in the light of selective and sequential U extractions performed on the soil samples. CONCLUSIONS The overall data clearly indicate that although DU was added to soil of the study area the phenomenon was spatially very limited and the absolute U concentrations usually did not reach very high figures with respect to natural ranges (Reimann and de Caritat, 1998). Absolute U concentrations in earthworms were normally low. This could mean that these animals are able to avoid the metal which seems to be present in soil mainly as discrete oxide particles. REFERENCES Reimann, C., de Caritat, P. (1998) Chemical Elements in the Environment. Springer Berlin, 397p. UNEP - United Nations Environment Programme (2001) Depleted Uranium in Kosovo. Post-Conflict Environmental Assessment, 184 pp.

Proc. 7th Intern. Conf. on the Biogeochem. of Trace Elements; Uppsala ’03

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