Natural radioactivity hazards of building bricks fabricated from saline soil of two districts of Pakistan

Abstract

Primordial radionuclides in building materials are one of the sources of radiation hazard in dwellings made of those materials. Activity concentrations of primordial radionuclides 40K, 226Ra and 232Th have been measured in house building bricks fabricated from saline soil. Forty samples of the bricks were collected from the brick fabrication sites and brick baking kilns in and around the saline soil areas of the districts of Lahore and Faisalabad in the Punjab province of Pakistan. The technique of gamma-ray spectroscopy using an HPGe detector with a PC-based multi-channel analyser was applied for determination of activity concentrations in the brick samples. The activity mass concentrations of 40K, 226Ra and 232Th measured in the brick samples were respectively 567.7 +/- 38.3 (493-631), 28.4 +/- 3.8 (23-35), and 56.0 +/- 4.6 (46-65) Bq kg(-1). The radiological hazards of the bricks were calculated using various models given in the literature. The radium equivalent activity was less than the accepted standard criterion value of 370 Bq kg(-1) and the values of other hazard indices were also below their limit values. The radiological hazard parameters of the bricks under investigation have been compared with those from other locations of Pakistan and also from some other countries in Asia.

Radiometric evaluation of natural radioactivity and radiation hazard indices in soils from quarries sites in southwestern Nigeria

“…Hin should be less than unity for the radiation hazard to be negligible. Internal exposure to radon is very hazardous which can lead to respiratory diseases like asthma (Tufail et al, 2007). Natural radionuclide in soil, rocks and sediment produce an external radiation field to which all humans are exposed.…”

Natural radioactivity and associated radiation hazards of some commonly used building materials in southwest Nigeria

“…To assess this threat, two radiation hazard indices were used in this study, which are: the internal hazard index and the alpha index. These indices are respectively given as: (Otoo et al, 2011) (4) (Tufail et al, 2007).…”

“…Also, the recommended exemption level and recommended upper limit of 226 Ra activity concentrations as applied in many countries of the world are 100 Bq.kg -1 and 200 Bq.kg -1 , respectively (Tufail et al, 2007), which implies that the exemption level and the recommended upper limit of I are 0.5 and 1.0, respectively. If the concentration of 226 Ra in any building material exceeds the upper limit of 200 Bq.kg -1 , it is not impossible that radon exhalation from the material could cause indoor radon buildup exceeding 200 Bq.m -3 .…”

“…Several national and regional surveys have been conducted to establish the radioactivity concentrations and radiological impact of various building materials such as sand, bricks, concrete, granite, cement, ceramic tiles, clay, etc. (Ingersoll, 1983;Berekta and Matthew, 1985;Malanca et al, 1993;Hewamanna et al, 2001;Khan and Khan, 2001;Stoulos et al, 2003;Xinwei, 2004;Papastefanou et al, 2005;Xinwei, 2005;Al-Jundi et al, 2006;Tufail et al, 2007;Bridigo Flores et al, 2008;Turhan et al, 2008;Righi et al, 2009;Hassan et al, 2010;Stojanovska et al, 2010;Otoo et al, 2011;etc.). In Nigeria, a few studies have focused on the radioactivity levels of building materials (Farai and Ademola, 2005;Farai and Ejeh, 2006;Farai and Isinkaye, 2009).…”

Environmental risk assessment of radon from ceramic tiles

“…Radon emanates from the earth, and on a smaller scale from certain construction materials (EC, 1999;Tufail et al, 2007;Cortina et al, 2008;Maged, 2009). It is present everywhere and in the open air it rapidly disperses and rarely reaches hazardous concentrations.…”