Assessment of natural radioactivity in ceramics imported of Sudan

The study presents the radioactivity concentration of ²³⁸U, ²³²Th and ⁴⁰K for 25 commercial ceramic samples, which is used as building materials in Sudan, Imported from China. A total of 25 different consignment samples were analyzed and the concentrations of radioisotopes were determined by Gamma spectroscopy using (Nal) detector. The detected values of concentrations of ²³⁸U, ²³²Th and ⁴⁰K were 182.9, 51.18 and 237.67 Bq/kg dry-weight respectively. Five different radiation indices, namely average radium equivalent (Ra_eq), the absorbed dose rate (D), the annual effective dose equivalent (AEDE), the external hazard index (H_ex), and the radioactivity level index (I_x) which indicate hazardous radiation were also determined. The results revealed that the average radium equivalent (Ra_aq), the absorbed dose rate (D), the annual effective dose equivalent (AEDE), external hazard index (H_ex), and the radioactivity level index (I_x) were 274.3915 Bq/kg, 122.02 nGy/h, the external hazard index (H_ex), and the radioactivity level index (I_x) were 274.3915 Bq/KG, 122.02 nGy/h, 122 mSv/yr, 0.74 and 1.89, respectively. The mean values of Ra_ex obtained were in good agreement with the international values, while the mean of D, and I_x were higher than the international values, and it found that.The results of AEDE for 14 samples are bout 10 -101% higher than the result international value (1mSv/yr) for the public the rest is lower than the permissible value for the international values. The measured activity concentrations for these radionuclides were compared with the reported data obtained from similar materials used in other countries and with typical world values. (Author)