Assessment of the average effective dose from the analysis of ~(226)Ra, ~(232)Th and ~(40)K in soil samples from Punjab, India

摘要

The activity concentrations of the natural radionuclides, namely ~(238)Ra, ~(232)Th and ~(40)K, are measured for soil samples collected from some locations of the Malwa region of Punjab. An HPGe detector, based on high-resolution gamma spectrometry system is used for the measurement of activity concentrations. The activity concentrations of ~(226)Ra, ~(232)Th and ~(40)K in the soil from the studied areas varies from 23.3 Bq kg~(-1) (Jagraon) to 43.6 Bq kg~(-1) (Ludhiana), 104 Bq kg~(-1) (Raikot) to 148 Bq kg~(-1) (Kauli) and 290 Bq kg~(-1) (Rajpura) to 394 Bq kg~(-1) (Sarhind) having an overall mean value of 32 Bq kg~(-1), 126 Bq kg~(-1) and 348 Bq kg-' respectively. The radium equivalent activity (Ra_(eq)) in these soil samples ranges from 200 Bq kg~(-1) (Jagraon) to 264 Bq kg~(-1) (Kauli) having a mean value of 237 Bq kg~(-1). Corresponding indoor and outdoor annual effective doses range from 0.45 to 0.59 mSv and 0.11 to 0.15 mSv and average 0.53 and 0.13 mSv. The external hazard index (H_(ex)) for soil samples of the study area are lower than unity; therefore, according to the Radiation Protection 112 (European Commission, 1999) report, soil from these regions is safe and can be used as a construction material without posing any significant radiological threat to population.