Measurement of annual effective dose and health risk assessment by measuring 238U, 232Th and 40K in soil samples using gamma ray spectroscopy

Gamma ray spectroscopy technique is used to measure annual effective dose and health risk assessment in some areas of western parts of Haryana. HPGe detector is preferred over Nal(Th) detector due to its high-resolution for measurement of natural radionuclides in soil samples. The measured values of activity concentrations of 238U, 232Th and 40K vary from 43.14 to 142 Bqkg-1, 50.31 to 124.34 Bqkg-1 and 593.37 to 1057.77 Bqkg-1 with overall mean values of 68.91, 82.79 and 775.04 Bqkg-1 respectively. The values of Radium equivalent (Raeq) activity estimated from the measurement of 238U, 232Th and 40K varies from 175.77 to 304.17 Bqkg-1. The absorbed dose rate in the study area ranges from 19.89 to 65.46 nGyh-1 for 238U, 31.34 to 77.46 nGyh-1 for 232Th, and 24.57 to 43.75 nGy h-1 for40K. The total absorbed dose rate in the study area ranges from 84.65 to 143.33 nGy h-1 with an average value of 115.43 nGy h-1. An attempt has also been made to estimate the annual effective radioactive dose for the residents. The calculated values of external hazard index (Hex.) for the soil samples of the study area range from 0.49 to 0.84. Since these values are lower than unity, therefore, there is no significant threat associated for the health risk to the residents of the study area. So soil from these areas can be used safely for construction material. (author)