COMMITTED EFFECTIVE DOSE DUE TO THE INTAKE OF 40K, 226Ra, 228Ra AND 228Th CONTAINED IN FOODS INCLUDED IN THE DIET OF THE RIO DE JANEIRO CITY POPULATION, BRAZIL

Annual effective dose due to the consumption of K-40, Ra-226, Ra-228 and Th-228 was estimated from high-resolution gamma spectrometry, food consumption data for the inhabitants of Rio de Janeiro City and dose coefficients published by the ICRP 119. A total of 31 samples of cereals, grains, vegetables, flours, liquid and perishables were analyzed. K-40 was measured in all samples, and bean sample presented highest specific concentration 489.36 +/- 23.70 Bq kg(-1). The highest specific concentration for Ra-226, Ra-228 and Th-228 was measured in pumpkin (7.82 +/- 1.09 Bq kg(-1)), carrot (30.18 +/- 1.99 Bq kg(-1)) and beet (2.43 +/- 0.48 Bq kg(-1)), respectively. The highest contribution to annual effective dose came from beans (556.3 mu Sv), potato (12.5 mu Sv), carrot (10.3 mu Sv), banana (4.7 mu Sv) and beet (3.3 mu Sv). It was observed that updates of daily food consumption values was the main reason for an up to 10-fold difference between the annual effective dose found in the present study and literature data.