Depleted uranium in environmental samples from Kuwait areas affected by the 1991 Gulf War

Top soils (0-5 cm), soil profiles (0-35 cm), water and vegetation samples collected in several locations of Kuwait considered relevant by the local authorities either because fighting took place in or around them or important from the public reassurance point of view (residential areas, presence of farms or drinking water wells) were investigated for the presence of depleted uranium (DU) by inductively coupled plasma mass spectrometry and alpha and beta gamma spectrometry. More than 200 samples were collected and analysed. The measurements were subjected to rigorous quality assurance and control procedures and the uncertainties carefully evaluated. The results indicated that: (a) in the urban areas only natural uranium was present in the soil, (b) in the farming areas soil, vegetable and brackish water from wells also contained uranium at concentrations of no radiological significance, (c) at the only place where drinking water is extracted from a water body at a depth of about 50 m (this is bottled and locally consumed) no DU was present, (d) along and around the main road to Iraq, were a long retreating convoy was destroyed in 1991, no DU residues are now present, (e) in the oil field south of Kuwait City, that were severely hit by DU ammunition, DU penetrators can still be found and there are spots (generally just below corroded penetrators) where DU concentration in soil can reach up to 50,000 or 100,000 Bq/kg, (f) in the places were the many vehicles hit by DU ammunition were temporarily stored after the war only one spot containing some DU in soil (41 Bq/kg) was identified, (g) at the site where accidentally a fire broke out in 1991 in a US military depot storing a large quantity of DU munitions, only a few top soil spots containing low quantities (∼ 90 Bq/kg) of DU were identified; the low DU concentration is the result of the cleaning conduced immediately after the explosion by the US forces and later on by the Kuwaiti authorities, and the complete reclamation of the site now in progress. (author)