Measurement of naturally occurring/fallout radioactive elements and assessment of annual effective dose in soil samples collected from four districts of the Punjab Province, Pakistan

Soil samples were collected from different localities of districts Jhelum, Chakwal, Rawalpindi and Attock, Punjab Province, Pakistan with an aim to measure naturally occurring radionuclides, namely Ra-226, Th-232, K-40 and fallout Cs-137 radionuclide using a P-type coaxial high purity germanium (HPGe) gamma-ray spectrometer. Measured specific activities of Ra-226, Th-232 and K-40 in these soil samples ranged from 26.02 +/- A 7.11 to 93.54 +/- A 8.13 Bq kg(-1), 29.34 +/- A 2.58 to 114.41 +/- A 2.80 Bq kg(-1) and 348.15 +/- A 3.20 to 752.98 +/- A 4.20 Bq kg(-1), respectively. Activity due to Cs-137 was observed in some locations which ranged from 0.4 +/- A 0.2 to 7.8 +/- A 0.3 Bq kg(-1). From the measured activity concentrations, radium equivalent activity concentrations were determined followed by calculations of mean absorbed dose rate and mean annual effective dose for the inhabitants of the studied area. The mean radium equivalent activity, internal and external hazard indices values came out to be 179.26 +/- A 11.93 Bq kg(-1), 0.64 +/- A 0.05 and 0.48 +/- A 0.03, respectively. Indoors and outdoor average annual effective dose values were found to be 0.42 +/- A 0.03 and 0.10 +/- A 0.01 mSv, respectively. Present data have been compared with the published data for other parts of the world and found to be safe for public and environment.