Assessment of radiological hazards of Lawrencepur sand, Pakistan using gamma spectrometry.

The Lawrencepur sand had remained refrigerated during a long period of glaciations in the study area. Owing to its derivation from the granitic rocks of the Himalayas and its preservation under glacial environment, the sand grains are still fresh and may contain high level of primordial radioactivity. For that reason, radiological hazards of Lawrencepur sand were assessed using a high-purity germanium gamma spectrometry technique. The average activity concentrations of (226)Ra, (232)Th and (40)K were found to be 15.97±3.05, 27.98±4.89 and 498.20±15.91 Bq kg(-1), respectively. These values are higher than those of the sands of many countries of the world but lower than those of some of the Pakistani, Indian and Egyptian sands. The outdoor and indoor hazard indices and annual effective doses of the Lawrencepur sand are higher than those of some of the sand deposits of European, African and American countries but lower than those of nearby Pakistani and Indian sands. However, the hazard indices and annual effective doses of the Lawrencepur sand are within the safe limits. Overall, the Lawrencepur sand does not pose any radiological health hazard as a building material.