Two radioecological surveys in the high background radiation are of Yangjiang, Guangdong Province, China: Contents of natural radionuclides in a certain snail (Achatina Fulica) and Cassava, and their transfer

The determined results showed that the radioactivity concentrations of 226Ra, 228Ra, 210Pb and 210Po in the snail meat and cassava root were of the order of 100-101 Bq.kg-1, but those of natural U and Th were of the order of 10-6-10-5 g.kg-1. The 228Ra concentrations in both were more than their 226Ra concentrations. U contents in soil, lived on by the snail and nurturing the cassava, were 17.7 and 3.2 mg.kg-1 respectively; but the Th contents in the soil were 39.1 and 10.5 mg.kg-1 respectively. According to the Annual Limit of Ingestion of 228Ra, limited consumption of the snail meat should be equal to 67 g per day. For the cassava root, critical nuclide is 210Pb; the limited consumption is estimated to be 324 g per day 12 refs, 10 tabs