The Radiological Impact of Agricultural Activities in an Area of High Natural Radioactivity

Abstract
The Pocos de Caldas Plateau, Brazil, with 70 radioactive anomalies is used for cattle, pigs and poultry production and for raising crops like potatoes, corn, brown beans and carrots. Data on the radioactivity concentration of natural radionuclides in air, soil, animal products, vegetables, water, sediment, external dose rates, and outdoor and indoor radon were used together with socio-economical information to estimate the radiological exposure from these agricultural activities in this high natural radioactivity area for the local rural and remote populations. For the local population agricultural products from the plateau contribute only relatively little (ca. 0.14-0.24 mSv.y-1) to the high radiation exposure (ca. 6-16 mSv.y-1) from external exposure and inhalation of radon and thoron daughters. However, the agricultural products carry a significant annual collective dose (ca. 14 man.Sv.y-1) to remote populations.