Radiological implications of Nagarparkar granite, Pakistan, as a building material

Abstract

The use of granite as a building material is a potential source of excessive radiation; therefore, natural radioactivity was measured in Nagarparkar granite using a HPGe γ -ray spectrometer. The average activities of 226 Ra, 232 Th and 40 K were found to be 25.93, 41.84 and 867.09 Bq.kg -1 , respectively. Based on the activities of 226 Ra, 232 Th and 40 K, assessment of the radiation indices, annual effective dose and excess lifetime cancer risk was made. All of these were found to be comparable with the worldwide granite averages . Overall, Nagarparkar granite, Pakistan, was evaluated as a safe building material. Based on the radiation indices, annual effective dose and excess life time cancer risk, Nagarparkar granite was found to be the 7th safest building material among the world’s granites. In granites of Pakistan, radioactivity increases from south to north. The granites with high radioactivity are located in the Eurasian-Indian Plate collision zone in Northern Pakistan.