Assessment Of Radioactivity Level In The Terrestrial And Marine Organisms In Yangjiang And Its Adjacent Areas (China)

In order to assess the radioactive level in the terrestrial and marine organisms in Yangjiang and the adjacent areas, Sr-90, gross beta and gamma-emitting radionuclides (U-238, Ra-226, Th-228, Ra-226, K-40, Cs-137, Cr-51, Fe-55, Mn-54, Co-58, Co-60 and Zn-65) were analyzed from 2011 to 2012. The annual effective doses were estimated in the high natural radioactive background areas in Yangjiang (HBRAYJ). The specific activities of U-238, Th-228, Ra-226, K-40 and Cs-137 in all organisms were <0.05-5.20, 0.30-14.50, 0.11-3.58, 11.1-148.0 and <0.003-0.088 Bq/kg, whilst Cr-51, Fe-55, Mn-54, Co-58, Co-60, Zn-65 and Ag-110m were below the minimum detectable activity. Sr-90 and gross beta specific activities were 20.0-143.0 and 0.021-0.316 Bq/kg. Results show that Th-228 was significantly higher than U-238 and Ra-226 of natural U series in organisms due to the rich-Th soils in the HBRAYJ; Th-228, Ra-226, K-40, Cs-137 and Sr-90 were greatly lower than the limited concentrations in Chinese foods. The internal dose mainly contributes to natural K-40, Ra-226 and Th-228. It is useful to provide some basic data and assess the radiological risk from the HBRAYJ and Yangjiang nuclear power plants in future.