Isotopic composition and origin of uranium and plutonium in selected soil samples collected in Kosovo

Soil samples collected from locations in Kosovo where depleted uranium (DU) ammunition was expended during the 1999 Balkan conflict were analysed for uranium and plutonium isotopes content (U-234, U-235, U-236, U-238, Pu-238, Pu239 + 240). The analyses were conducted using gamma spectrometry (U-235, U-238), alpha spectrometry (Pu-238, Pu239 + 241), inductively coupled plasma-mass spectrometry (ICP-MS) (U-234, U-235, U-236, U-238) and accelerator mass spectrometry (AMS) (U-236). The results indicated that whenever the U concentration exceeded the normal environmental values (similar to2 to 3 mg/kg) the increase was due to DU contamination. U-236 was also present in the released DU at a constant ratio of U-236 (mg/kg)/U-238 (mg/kg) = 2.6 x 10(-5), indicating that the DU used in the ammunition was from a batch that had been irradiated and then reprocessed. The plutonium concentration in the soil (undisturbed) was about 1 Bq/kg and, on the, basis of the measured Pu-238/(239) Pu+ 240, could be entirely attributed to the fallout of the nuclear weapon tests of the 1960s (no appreciable contribution from DU). (C) 2002 Elsevier Science Ltd. All rights reserved.