Radioecology teaching: evaluation of the background radiation levels from areas with high concentrations of radionuclides in soil

Abstract

The study of environmental radioactivity is a topic which is not usually included in physics courses in Brazilian and Latin American universities. Consequently, high-school teachers are not able to show experimentally or discuss with their students the effects of exposure to terrestrial radiation. This paper presents a laboratory experiment in a teaching programme on the physics of ionizing radiation. It is based on the evaluation of the background radiation levels from areas with high concentrations of natural or artificial radionuclides in the soil. A brief analysis of the theory behind the technique and a description of some measurements, including their interpretations, are presented.

Correlations between radiometric analysis of Quaternary deposits and the chronology of prehistoric settlements from the southeastern Brazilian coast

“…Although the NaI(Tl) g-ray spectrometer has a poor energy resolution, it is suitable for the purposes of the present work, since its high efficiency allows fast and precise determination of K, U and Th concentrations in rock, soil or sand samples. The accuracy of the energy calibration depends on possible interferences of each nuclide in each peak region (Grasty et al, 1991;Chiozzi et al, 2000;Anjos et al, 2005Anjos et al, , 2004. The procedures for calibration and measurement described by Grasty et al (1991) and Chiozzi et al (2000) were adopted in the present work.…”

226Ra, 232Th and 40K concentrations in igneous rocks from eastern desert, Egypt and its radiological implications

“…; EC, 1999;Tzortzis et al, 2003;Anjos et al, 2004). These results are of great interest in theTable 1Analytical results for the activity concentrations of 226 Ra, 232 Th and of 40 K (Bq kg −1 ) determined for each of the measured samples together with their total uncertainties radium-equivalent, (external, internal) hazard, total absorbed dose and effective dose rate at Um Taghir area…”

Natural radionuclide distribution in Brazilian commercial granites

“…Consequently, the measurements of thorium, uranium and potassium concentrations of different granite samples result in individual differentiation sequences. From the 232 Th, 238 U and 40 K activity concentrations obtained for each sample, it is possible to evaluate their respective dose rates in air, when these stones are used as tiling rocks (UNSCEAR, 1993(UNSCEAR, , 2000EC, 1999;Tzortzis et al, 2003;Anjos et al, 2004). These results are of great interest in the environmental radiological protection study, since granites are widely used as building and ornamental materials, including indoor covering.…”