Internal Exposure of Public in Lithuania Due to the Radioactively Contaminated Food

Abstract

The paper concerns the estimation of doses due to natural alpha and beta emitters in food and drinking water in Lithuania. Dose estimation is done on the results of gross alpha and gross beta measurements in mixed diet and drinking water. Sampling and measurements were performed at the Radiation Protection Centre during 2005 and 2006. For the mixed diet the sampling was performed on monthly basis in the cantina of hospital. Drinking water was sampled at 8 locations in the country, from 8 water supply systems and 24 private wells quarterly. Dose estimation shows that the highest dose due to the alpha and beta radionuclides in the mixed diet should be less than 0.245 mSv and 40K gives 61–63% of the this dose. Dose calculation for the public due to the alpha and beta radionuclides in the drinking water indicates that the highest dose may be due to the beta emitters but not due to 40K in water from wells and the dose should be less than 0.042 mSv per year. Doses from man made radionuclides 90Sr and 137Cs in food are much lover than those of the natural origin. Doses due to natural radionuclides in food for public in Lithuania are lower than in countries with the igneous and metamorphic rock type and the maximum value is lower than the average world value from the terrestrial radionuclides ingested and received by inhalation.