Akademik Veri Yönetim Sistemi
RADIOCHIMICA ACTA, cilt.106, sa.5, ss.401-411, 2018 (SCI-Expanded)
The aim of this study is to determine the levels of background radiation in nine districts of Kirikkale, Turkey. The outdoor gamma dose rate in the air was measured using a portable digital environmental radiation detector at 170 locations. The mean outdoor gamma dose rate in the air was determined as 121 nGy h(-1) with a range between 23 and 320 nGy h(-1). The annual effective dose for districts was between 0.04 and 0.59 mSv year(-1) with a mean value of 0.23 mSv year(-1). Excess lifetime cancer risk values for districts ranged from 0.14 x 10(-3) to 2.07 x 10(-3) with a mean of 0.80 x 10(-3). The activity concentrations of Ra-226, Th-232, K-40 and Cs-137 in 84 soil samples were determined using HPGe detector. The mean activity values (ranges) of Ra-226, Th-232, K-40 and Cs-137 in soil samples were found to be 20.4 (4.9 +/- 3.0-53.0 +/- 0.8) Bq kg(-1), 38.8 (3.7 +/- 0.2-163.5 +/- 1.8) Bq kg(-1), 598.0 (108.5 +/- 70.2-1500.5 +/- 38.7) Bq kg(-1) and 3.9 (0.2 +/- 0.1-11.9 +/- 0.7) Bq kg(-1), respectively. The mean activity concentration of Th-232 and K-40 was higher than the world's mean value. The mean radium equivalent activity was 119.76 Bq kg(-1) which is lower than the recommended maximum value of 370 Bq kg(-1). The mean external terrestrial gamma dose rate was found to be 56.71 nGy h(-1). This mean value was lower than the world mean of 60 nGy h(-1). The calculated external hazard value was 0.32 and within the acceptable limit which is less than unity (H-ex <= 1). The indoor radon concentration in 150 houses for the summer and winter seasons was determined using solid state nuclear track detector (CR-39). The mean indoor concentration for the summer season was found to be 63.27 Bq m(-3) ranging from 14.0 +/- 1.5 to 288.0 +/- 21.9 Bq m(-3). On the other hand, the mean indoor concentration in the winter season was found to be 86.94 Bq m(-3) ranging from 17.0 +/- 4.5 to 484.0 +/- 26.9 Bq m(-3). The present results showed that the radon activity concentrations in winter were 42.3 % higher than in the summer. The mean annual effective dose equivalent and lifetime cancer risk were also calculated.