Assessment of Radioactivity Level in the Terrestrial and Marine Organisms in Yangjiang and Its Adjacent Areas (China)

Abstract

In order to assess the radioactive level in the terrestrial and marine organisms in Yangjiang and the adjacent areas, 90Sr, gross beta and gamma-emitting radionuclides (238U, 226Ra, 228Th, 226Ra, 40K, 137Cs, 51Cr, 55Fe, 54Mn, 58Co, 60Co and 65Zn) 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 238U, 228Th, 226Ra, 40K and 137Cs 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 51Cr, 55Fe, 54Mn, 58Co, 60Co, 65Zn and 110mAg were below the minimum detectable activity. 90Sr and gross beta specific activities were 20.0–143.0 and 0.021–0.316 Bq/kg. Results show that 228Th was significantly higher than 238U and 226Ra of natural U series in organisms due to the rich-Th soils in the HBRAYJ; 228Th, 226Ra, 40K, 137Cs and 90Sr were greatly lower than the limited concentrations in Chinese foods. The internal dose mainly contributes to natural 40K, 226Ra and 228Th. It is useful to provide some basic data and assess the radiological risk from the HBRAYJ and Yangjiang nuclear power plants in future.