The investigation of radionuclide concentrations in soil and lifetime cancer risk due to gamma radioactivity in Zonguldak, Turkey

The distributions of 226Ra, 232Th, 40K and 137Cs activity concentrations were determined using a high-purity germanium detector in uncultivated surface soil samples collected from Zonguldak. The range of 226Ra, 232Th, 40K and 137Cs activity concentrations varied from 10.5 ± 2.0 to 98.0±4.3 Bqkg-1 (mean value 28.8 ±4 Bqkg-1), from 12.9 ± 3.4 to 53.2 ± 5.1 Bqkg-1 (mean value 29.6 ± 3 Bqkg-1), from 190 ± 22 to 808 ± 43 Bqkg-1 (mean value 395 ± 31 Bqkg-1) and from < 0.5 to 47.1 ± 3.8 Bqkg-1 (mean value 12.5 ± 2 Bqkg-1), respectively. In addition, the mean outdoor absorbed dose rates in air (terrestrial, terrestrial+cosmic), annual effective dose equivalent, radium equivalent activity and external hazard index were found to be 48 nGy h-1 (terrestrial), 56 nGy h-1 (terrestrial+cosmic), 58 µSvy-1, 101 Bqkg-1 and 0.27, respectively. The evaluated excess lifetime cancer risks (ELCRs) varied from 0.13 × 10-3 to 0.36 × 10-3 with a mean value of 0.20 × 10-3.Firat University Scientific Research Projects Management Unit: 2013-76962555-01The authors wish to thank Scientific Research Projects Unit of Bülent Ecevit University (Project No: 2013-76962555-01