Radionuclide concentrations in soil and lifetime cancer risk due to gamma radioactivity in Kirklareli, Turkey.

Determination of radioactivity levels and hazards of soil and sediment samples in Firtina Valley (Rize, Turkey).

Determination of thorium, uranium and potassium elemental concentrations in surface soils in Cyprus

A survey was carried out to determine activity concentration levels and associated dose rates from the naturally occurring radionuclides Th-232, U-238, and K-40, in the various geological formations appearing throughout the geographically accessible area of Cyprus, by means of high-resolution gamma-ray spectrometry. A total number of 115 representative soil samples were collected from all over the bedrock surface of the island, based on the different lithological units of the study area, sieved through a fine mesh, sealed in 1000-mL plastic Marinelli beakers, and measured in the laboratory with respect to their gamma radioactivity for a counting time of 18 hours each. From the measured spectra, activity concentrations were determined for Th-232 (range from 1.0x10^-2 to 39.8 Bq/kg), U-238 (from 1.0x10^-2 to 39.3 Bq/kg) and K-40 (from 4.0x10^-2 to 565.8 Bq/kg). Gamma absorbed dose rates in air outdoors were calculated to be in the range of 1.1x10^-2 - 51.3 nGy/h, depending on the geological features, with an overall mean value of 8.7 nGy/h and a standard deviation of 8.4 nGy/h. This value is by a factor of about 7 below the corresponding population-weighted world-averaged value of 60 nGy/h reported by UNSCEAR (2000), and one of the lowest that has been reported from similar investigations worldwide. Assuming a 20% occupancy factor, the corresponding effective dose rates outdoors equivalent to the population were calculated to be between 1.3x10^-2 and 62.9 micro Sv/y, with an arithmetic mean value of 10.7 micro Sv/y and a standard deviation of 10.3 micro Sv/y.

A Bayulken

Papers

Assessment of gamma dose rates around Istanbul (Turkey)