Dose rates and seasonal variations of [sup.238]U, [sup.232]Th, [sup.226]Ra [sup.40]K and [sup.137]Cs radionuclides in soils along Thrace, Turkey

Concentrations of [sup.238]U, [sup.232]Th, [sup.226]Ra, [sup.40]K and [sup.137]Cs are measured in collected soil samples from various locations in the Thrace region of Turkey. The activity concentrations range from 12.82 to 101.75 Bq [kg.sup.-1] d.w. (dry weight) for [sup.238]U, from 5.16 to 73.34 Bq [kg.sup.-1] d.w. for [sup.232]Th, from 185.54 to 5399 Bq [kg.sup.-1] d.w. for [sup.40]K and from 11.42 to 90.73 Bq [kg.sup.-1] d.w. for [sup.226]Ra. In addition to naturally occurring radionuclides, [sup.137]Cs activity concentration is determined between 3.05 and 46.78 Bq [kg.sup.-1] d.w. for soil samples. Determination of the radiological hazard is achieved through calculations of the external terrestrial gamma dose rate in air (nGy [h.sup.-1]) and annual effective dose rate (mSv [year.sup.-1]) and the results are compared with the similar works in different countries. Keywords Natural radionuclide * Uranium * Thorium * Radium * Cesium * Potassium * Soil