Abstract:

HaThanh - DauCo areas, DongCuu village with radioactive thorium - uranium anomalies within the pegmatite body, radioactive anomalies in granite aplite, pegmatite granite, mica schist amphibolite. Radioactive anomaly in nature mainly thorium, uranium not high. In this work, the external and internal (through breathing and eating) effective dose were estimated based on the measurements of gamma dose rate, radioactive concentration gas of radon and thoron in 42 households and radioactivity analysis of food and water samples in the survey area. The results show that 5/42 of households have indoor gamma dose rate larger than 0.6μSv/h, the level of dose rate from 5.03 to 18.63 mSv/year apprear in 16/42 households, and of which 3 households suffer a larger dose of 10 mSv/year. Thoron radioactivity gas concentrations contributed significantly to the results of internal effective dose and total effective dose in the households where the dose rate is high.