Depleted Uranium Contamination and Radiological Risks of Surface Soils, River Sediments, and Roadside Deposits

The occurrence of sand and dust storms (SDS) in Iran has raised many concerns about the possibility of environmental and public health hazards caused by dust particles and pollutants existed in these particles. Therefore, the purpose of this study was to investigate the possibility of contamination of surface soil, river sediments, and roadside deposits with radioactive materials, especially depleted uranium (DU) in the areas affected by SDS. The radioactive activity of the samples was measured by gamma spectroscopy with a high-purity germanium detector. The average activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰ K were 11.19, 8.05, and 76.05 Bq/kg. The average ratio of ²³⁸U/²³⁵U was 89 indicating the possibility of the presence of DU in the soil samples. The average values of R_m (the share of ²³⁵U in total uranium) and DU_m were 0.55% (lower than natural uranium, 0.72) and 33% (indicating the presence of 33% DU on average in the samples). Based on ²³⁸U/²²⁶Ra activity, two samples (S11 and S12) should be considered as DU-contaminated. Almost the obtained results for all radiological risk indices showed lower values than the world average and the possibility of creating a low risk for working people, residents, visitors, and travelers passing through these areas.