title: Assessment of Natural Radioactivity Levels and Potential Radiological Risks of Common Building Materials Used in Bangladeshi Dwellings.
abstract: The concentrations of primordial radionuclides (226Ra, 232Th and 40K) in commonly used building materials (brick, cement and sand), the raw materials of cement and the by-products of coal-fired power plants (fly ash) collected from various manufacturers and suppliers in Bangladesh were determined via gamma-ray spectrometry using an HPGe detector. The results showed that the mean concentrations of 226Ra, 232Th and 40K in all studied samples slightly exceeded the typical world average values of 50 Bq kg(-1), 50 Bq kg(-1) and 500 Bq kg(-1), respectively. The activity concentrations (especially 226Ra) of fly-ash-containing cement in this study were found to be higher than those of fly-ash-free cement. To evaluate the potential radiological risk to individuals associated with these building materials, various radiological hazard indicators were calculated. The radium equivalent activity values for all samples were found to be lower than the recommended limit for building materials of 370 Bq kg(-1), with the exception of the fly ash. For most samples, the values of the alpha index and the radiological hazard (external and internal) indices were found to be within the safe limit of 1. The mean indoor absorbed dose rate was observed to be higher than the population-weighted world average of 84 nGy h(-1), and the corresponding annual effective dose for most samples fell below the recommended upper dose limit of 1 mSv y(-1). For all investigated materials, the values of the gamma index were found to be greater than 0.5 but less than 1, indicating that the gamma dose contribution from the studied building materials exceeds the exemption dose criterion of 0.3 mSv y(-1) but complies with the upper dose principle of 1 mSv y(-1).
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia; Bangladesh Atomic Energy Commission, Dhaka-1207, Bangladesh.
authors.forename: Khandoker
authors.initials: K
authors.lastname: Asaduzzaman
authors.affiliation: Institute of Educational Leadership, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Farhana
authors.initials: F
authors.lastname: Mannan
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Mayeen Uddin
authors.initials: MU
authors.lastname: Khandaker
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Mohideen Salihu
authors.initials: MS
authors.lastname: Farook
authors.affiliation: Department of Prosthetic Dentistry, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Aeman
authors.initials: A
authors.lastname: Elkezza
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Yusoff Bin Mohd
authors.initials: YB
authors.lastname: Amin
authors.affiliation: Institute of Educational Leadership, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Sailesh
authors.initials: S
authors.lastname: Sharma
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Hasan Bin
authors.initials: HB
authors.lastname: Abu Kassim
mesh_terms: D001459:Bangladesh; D060729:Coal Ash / Q000032:analysis; D003252:Construction Materials / Q000032:analysis*; D011197:Potassium Radioisotopes / Q000032:analysis*; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000379:methods; D011883:Radium / Q000032:analysis*; D013051:Spectrometry, Gamma / Q000379:methods; D013910:Thorium / Q000032:analysis*
chemical_list: D060729:Coal Ash; D011197:Potassium Radioisotopes; D013910:Thorium; D011883:Radium