Abstract:

The distribution of 226Ra, 232Th, and 40K in 70 granite samples obtained from 13 Western Anatolian plutons (Turkey) was measured by using γ-ray spectroscopy. The activities of the measured radionuclides varied up to 259 Bq kg-1 for 226Ra, up to 241 Bq kg?1 for 232Th, and up to 2518 Bq kg-1 for 40K, with mean values of 66 (±44), 90 (±47), and 1097 (±410) Bq kg-1, respectively, which are smaller than the mean values given for granites worldwide. The mean value of the increase on the external γ-radiation effective dose rate is 0.21 (±0.09) mSv year-1, varying by <1 mSv year-1. The mean value of the internal α-radiation was 0.15 (±0.10) mSv year-1, varying <0.5 mSv year-1. Most of the samples cause an increase to both the external and internal dose by <30%, which is smaller than the permitted limit. Therefore, there is no radiological risk from the usage of the samples studied as decorative and ornamental building materials.

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