Radiological hazards due to naturally occurring radionuclides in the selected building materials used for the construction of dwellings in four districts of the Punjab Province, Pakistan

This paper presents the finding of a study undertaken to determine the naturally occurring radionuclides present in commonly used building materials for dwellings and workplaces in four districts of the Punjab Province, Pakistan. The concentrations of Ra-226, Th-232 and K-40 were measured by using gamma-ray spectroscopy. A total of 80 samples of building materials were collected from various manufacturers and suppliers of the studied area. The specific activities of Ra-226, Th-232 and K-40 were measured in building samples, and results ranged from minimum values of 91, 92 and 278 Bq kg(1) to maximum values of 1065, 1335 and 91421 Bq kg(1) with mean values of 423, 483 and 37616 Bq kg(1), respectively. From the measured activity concentrations, equivalent radium (Ra-eq), terrestrial absorbed dose rate, annual effective dose as well as external and internal hazard indices were calculated and found to range from 527 to 27415 Bq kg(1), 233 to 130 6 nGy h(1), 0.150.02 to 0.800.03 mSv, 0.140.02 to 0.750.04 and 0.20.02 to 0.980.05, respectively. These results were comparable to the results of similar studies undertaken locally and in other countries. The samples considered were safe for use in construction of dwellings in the study area and do not pose any significant source of radiation hazard.