Environmental Risk Assessment of Combined Radioactive and Chemical Pollution in Soil

The purpose of the study is to define the level of combined radiological and chemical contamination from the activities of soil and moss samples collected from the Eastern Black Sea region in Turkey and to assess the risk caused by the environmental radioactivity and chemical pollutants. The gamma, gross beta and gross alpha activities were measured in the soil and moss samples. The 238U, 232Th, 40K and 137Cs activity concentrations in the soil samples were measured in the range of 7.0 and 72 Bq kg-1 for 238U, 8.1 and 86 Bq kg-1 for 232Th, 203 and 1190 Bq kg-1 for 40K and 0.71 to 66 Bq kg-1 for 137Cs. In the moss samples, the 137Cs, 40K, 232Th, and 238U activity concentrations were found in the range of 1.03�0.27-24.23�1.39, 137�7-1340�68, 3.58�0.32-5.93�0.44 and 0.88�0.09-2.25�0.23 Bq kg-1, respectively. Contamination from toxic metals in the soils is categorized into enrichment factor, geo-accumulation risk, potential ecological risk and pollution load index. Co, Ni, As and Pb enrichments were determined in the extreme category in the 6 sampling sites. The pollution load index for the selected metals was found to be greater than 1. The geo-accumulation index in one sampling site showed contamination from heavy to severe levels of arsenic and lead.