Preliminary studies on 226Ra, 228Ra, 228Th and 40K concentrations in foodstuffs consumed by inhabitants of Accra metropolitan area, Ghana

Knowledge of radioactivity levels in human diet is of particular concern for the estimation of possible radiological hazards to human health. However, very few surveys of radioactivity in food have been conducted in Ghana. The natural radionuclides Ra-226, Ra-228, Th-228 and K-40 were measured in the foodstuffs using gamma ray spectrometry. All samples were found to contain high K-40 content in the range 87.77-368.50 Bq kg(-1). The maximum concentration of Th-228 and K-40 were found in cassava to be 14.93 +/- A 3.86 and 368.50 +/- A 19.20 Bq kg(-1), respectively. The total annual committed effective dose was estimated to be 4.64 mSv. The daily intake of radionuclides from food consumption reveals that cassava and plantain are the highest contributors, while millet is the lowest. The daily radionuclide intake from the foodstuffs consumed by the general public was 411.32 Bq and the daily internal dose resulting from ingestion of the radionuclides in the foodstuffs was 0.01 mSv. The radionuclide concentrations were comparable with those reported from other countries.