TÜRKİYE'DE ÇEVRESEL RADYOAKTİVİTE : ENVIRONMENTAL RADIOACTIVITV iN TURKISH ENVIRONMENT

Radioactivity can be found at di􀄀erent levels in various environments such as soil, rock, water food and in air. In principle, the source of environmental radioactivity can be classified into two groups named natural and manmade. Natural radiation sources can have cosmic or terrestrial origin. Terrestrial radiation sources originate from primordial radionuclides in the earth's crust that have existed since the beginning of the world. The most important primordial radionuclides in terms of radiological risk for humans are 40K, 238U, 232Th and their decay products of both natural radioactive series. 87Rb and 235U are second-rate primordial radionuclides, to be neglected by their contribution to the human dose. Generally, the concentrations of natural radionuclide activity observed in soils reflect the natural background concentrations of the rocks from which they are derived. On the other hand, human activities such as burning of coal to provide electrical energy and application of artificial fertilizers containing phosphates to increase agricultural production causes the enrichment of natural radioactivity concentrations in the environment. Naturally occurring radioactivity is of immediate and crucial concern to the people and authorities responsible for environmental protection. Because of this reason many studies and projects have been devoted for determining and monitoring of radiation levels in various environments. Continued studies on the radiation levels in various environments either from natural radiation sources or releasing radionuclides into the environment by human activities can contribute to our knowledge about radiation risk and dangers of radiation.