Direct gamma dose rate measurement and assessment of excess lifetime cancer risk.

In this study, in some neighborhoods in Kahramanmaras province of Turkey, indoors and outdoors direct gamma dose rate measurements have been done. All of the gamma dose rate measurements have been made at ground level and at the height of 1 m from the ground. The median values of the gamma dose rates on the ground and 1 m above the ground indoors are 70.34 ± 7.74 and 49.53 ± 5.39 nGy h-1, respectively. Outdoor measurements have been carried out on both soil and asphalt floors. The average values of gamma dose rate on the ground and at a height of 1 m outdoors (soil floor) are 68.16 ± 7.49 and 53.50 ± 5.88 nGy h-1, respectively. The mean values of gamma dose rate on the ground and 1 m above the ground outdoors (asphalt floor) are 61.63 ± 6.77 and 48.69 ± 5.35 nGy h-1, respectively. Indoor and outdoor average gamma dose rates are below the mean world. In addition, using the measured gamma dose rate values, annual effective dose equivalent (AEDE) and excess lifetime cancer risk (ELCR) for adults have been calculated. The total AEDE and ELCR (on soil floors and indoors at 1 m above ground level) are 0.31 ± 0.03 mSv y-1 and 1.08 ± 0.10 × 10-3, respectively. The total AEDE and ELCR (on asphalt floors and indoors at 1 m above ground level) are 0.30 ± 0.03 mSv y-1 and 1.06 ± 0.10 × 10-3, respectively. The AEDE and ELCR for adults living in the neighborhoods within the scope of the study in Kahramanmaras city center within 1 y are lower than the average world.

Natural radioactivity in soil samples taken from Kahramanmaras provincial center.

The levels of 238U, 232Th, and 40K with gross alpha and beta values in soils collected from the Kahramanmaras city center were measured in this study, and the annual effective dose equivalent (AEDE), excessive lifetime cancer risk (ELCR), and terrestrial absorbed gamma dose rates were calculated for gamma radiation from 238U, 232Th, and 40K radionuclides. The samples' gross alpha and beta radioactivity concentrations, respectively, range from 0.06 ± 0.01 Bq/kg to 0.45 ± 0.04 Bq/kg and 0.14 ± 0.02 Bq/kg to 0.95 ± 0.09 Bq/kg. The Kahramanmaras province's soil samples have mean gross alpha and beta radiation values of 0.25 ± 0.03 Bq/kg and 0.52 ± 0.05 Bq/kg, respectively. 238U, 232Th, and 40K activity concentrations in soil samples range from 2.32 ± 0.2 Bq/kg to 40.10 ± 1.4 Bq/kg, 0.60 ± 0.03 Bq/kg to 10.47 ± 1.01 Bq/kg, and 11.60 ± 1.01 Bq/kg to 160.84 ± 4.6 Bq/kg, respectively. 238U, 232Th, and 40K each had average activity concentrations of 11.50 ± 1.1, 4.50 ± 0.4, and 62.20 ± 1.6 Bq/kg in soil, respectively. The annual effective dose equivalent (AEDE), excessive lifetime cancer risk (ELCR), and terrestrial absorbed gamma dose rate range from 0.01 ± 0.01 µSv y-1 to 0.03 ± 0.02 µSv y-1, and 0.01 ± 0.01 × 10-3 to 0.12 ± 0.03 × 10-3, 1.72 ± 0.01 nGy h-1 to 25.05 ± 0.21 nGy h-1, respectively. Additionally, the average annual effective dose equivalent (AEDE), average excessive lifetime cancer risk (ELCR), and average terrestrial absorbed gamma dose rates are 0.01 ± 0.01 µSv y-1, and 0.05 ± 0.02 × 10-3, 9.81 ± 0.09 nGy h-1, respectively. The acquired data were compared to both domestic and international standards.

Radioactivity amounts, annual effective dose rate, and lifetime cancer risk estimation of some vegetable and fruit samples cultivated in Kahramanmaras, Turkey.

In this research, examples of the fruits and vegetables cultivated in Kahramanmaras, 238U, 232Th, and 40K levels, were detected, and in the case of consumption of these vegetables and fruits, for several age categories (adults, children (10 years old), and infants), annually effective dose rates and lifetime cancer risks were calculated. In fruit samples, concentrations of 238U, 232Th, and 40K ranged from under detection limit (UDL) to 15.29 ± 1.14 Bq/kg, 0.30 ± 0.01 to 13.23 ± 1.60 Bq/kg, and 5.82 ± 0.21 to 179.82 ± 1.34 Bq/kg, respectively. The mean concentrations of 238U, 232Th, and 40K in fruit samples were 5.31 ± 0.44 Bq/kg, 2.72 ± 0.26 Bq/kg, and 56.84 ± 0.57 Bq/kg, respectively. In vegetable samples, concentrations of 238U, 232Th, and 40K ranged from 0.48 ± 0.04 to 11.77 ± 0.95 Bq/kg, 0.55 ± 0.04 to 4.57 ± 0.44 Bq/kg, and 9.32 ± 0.43 to 52.44 ± 0.52 Bq/kg, respectively. The mean concentrations of 238U, 232Th, and 40K in the vegetable samples were 6.58 ± 0.65 Bq/kg, 2.72 ± 0.27 Bq/kg, and 27.09 ± 0.27 Bq/kg, respectively. The mean annual effective dose rates for adults, children (10 years old), and infants in fruit samples were 0.184 ± 0.001 mSv/y, 0.288 ± 0.002 mSv/y, and 0.304 ± 0.003 mSv/y, respectively. The average lifetime cancer risks for adults, children (10 years old), and infants in fruit samples were 0.647 ± 0.006 × 10-4, 1.011 ± 0.010 × 10-4, and 1.067 ± 0.010 × 10-4, respectively. The mean annual effective dose rates for adults, children (10 years old), and infants in the vegetable samples were 0.118 ± 0.001 mSv/y, 0.128 ± 0.001 mSv/y, and 0.086 ± 0.001 mSv/y, respectively. The mean lifetime cancer risks for adults, children (10 years old), and infants in vegetable samples were 0.416 ± 0.004 × 10-4, 0.449 ± 0.004 × 10-4, and 0.304 ± 0.003 × 10-4, respectively.

Measurement of gross alpha and gross beta activity concentrations in human tooth.

The gross alpha and gross beta activity concentrations were measured in human tooth taken from 3 to 6 age-groups to 40 and over ones. Accumulated teeth samples are investigated in two groups as under and above 18 years. The gross alpha and beta radioactivity of human tooth samples was measured by using a gas-flow proportional counter (PIC-MPC 9604-alpha/beta counter). In tooth samples, for female age-groups, the obtained results show that the mean gross alpha and gross beta activity concentrations varied between 0.534-0.203 and 0.010-0.453 Bq g(-1) and the same concentrations for male age-groups varied between 0.009-1.168 and 0.071-0.204 Bq g(-1), respectively.