ASSESSMENT OF NATURAL RADIOACTIVITY CONCENTRATIONS AND GAMMA DOSE RATE LEVELS IN KAYSERI, TURKEY

This study assesses the level of background radiation for Kayseri province of Turkey. Natural radionuclide activity concentrations in soil samples were determined using high-resolution gamma spectroscopy. Outdoor gamma dose measurements in air at 1 m above ground level were determined using a portable gamma scintillation detector. The obtained results of uranium and thorium series as well as potassium (K-40) are discussed. The present data were compared with the data obtained from different areas in Turkey. From the measured gamma-ray spectra, the average activity concentrations were determined for U-238 (range from 3.91 to 794.25 Bq kg(-1)), Th-232 (range from 0.68 to 245.55 Bq kg(-1)) and K-40 (range from 23.68 to 2718.71 Bq kg(-1)). The average activity concentrations of U-238, Th-232 and K-40 were found to be 35.51, 37.27 and 429.66 Bq kg(-1), respectively, and 11.53 Bq kg(-1) for the fission product Cs-137. The highest values of U-238, Th-232 and K-40 concentrations (794.25 Bq kg(-1), 245.55 Bq kg(-1), 2718.71 Bq kg(-1), respectively) were observed in abnormal samples at Hayriye village. The average outdoor gamma dose rate in air at 1 m above the ground was determined as 114.43 nGy h(-1). Using the data obtained in this study, the average annual effective dose for a person living in Kayseri was found to be about 140.34 mu Sv

Assessment of environmental radioactivity for Sanliurfa region of southeastern Turkey

This study assesses the level of background radiation for Sanliurfa province of southeastern Turkey. Measurements of outdoor gamma radiation (of terrestrial and cosmic origin) in air were performed at 112 locations using a plastic scintillator and the average absorbed dose was found as 60.9 nGy/h (corresponding to an effective close of 74.7 mu Sv/y). The radionuclide activity concentrations in 45 soil samples collected from the study area were measured through gamma-ray spectrometry and the average activities were determined as 20.8. 24.95 and 298.6 for the natural radionuclides U-238, Th-232 and K-40, respectively, and 9.08 Bq/kg for the fission product Cs-137. The natural radioactivity sources resulted in an effective dose of 46.9 mu Sv/y. The radioactivity levels of 53 drinking water samples were measured as 0.038 Bq/l for gross-alpha activity and 0.1324 Bq/l for gross-beta activity using gross-alpha and gross-beta counting methods (equivalent to a,in effective dose of 7.76 mu Sv/y). When compared with the data available for other Turkish cities, the outdoor gamma doses and soil radioactivity concentrations obtained in this study indicate a background radiation level that falls within natural limits. Oil the other hand, the measured gross-alpha and -beta activities in drinking water are relatively higher. (c) 2007 Elsevier Ltd. All rights reserved

A study of environmental radioactivity measurements for Cankiri, Turkey

This study is the first to assess the level of background radiation for the Cankiri province of Turkey. Indoor air radon concentrations were determined using Columbia Resin-39 nuclear track detectors and the average Rn-222 activity was found to be 44 Bq m(3) (equivalent to an annual effective dose of 1.1 mSv). Measurements of gamma doses in outdoor air were performed using a portable plastic scintillation detector and the average gamma absorbed dose rate was found to be 8 R h(1) (corresponding to an annual effective dose of 87.7 Sv). Radionuclide activity concentrations in soil samples were measured through gamma-ray spectrometry and the average activities were determined as 17.7, 22.3, 357 and 4.1 Bq kg(1) for the radionuclides U-238, Th-232, K-40 and Cs-137, respectively. The average annual effective dose from the natural radioactivity sources (U-238 series, Th-232 series and K-40) was calculated to be 44.4 Sv. Radioactivity levels of drinking water samples were carried out using a low-background proportional counter and the average gross alpha and beta activities were obtained as 0.25 and 0.26 Bq l(1), respectively (equivalent to an annual effective dose of 184 Sv). The average radon concentrations in indoor air and the average radionuclide activities in soil were found to be lower than most Turkish cities while higher levels of outdoor gamma dose rate and water radioactivity were observed. The results of this study showed that the regions background radioactivity level differs considerably from the reported data for Turkish cities