Investigations of Natural Radioactivity, Radon Levels, and Soil Properties in Kpando Municipality, Volta Region, Ghana

Abstract

This study measured natural radioactivity, indoor radon, radon exhalation rate and soil properties in the Kpando Municipality of Volta Region, Ghana. 120 dwellings, and 51 soil samples from Torkor, Agbenoxoe and Tsakpa in the Kpando Municipal were studied for indoor radon, radon exhalation rates, radionuclides and soil properties using CR – 39 detectors, gamma spectrometry and Gravimetric techniques. The radionuclides and radiation hazards associated with soil samples were found to vary as: 226Ra (2.80 to 53.30 Bq/kg), 232Th (3.40 to 58.80 Bq/kg), 40K (62.70 to 421.60 Bq/kg), indoor absorbed dose rate (13.72 to 138.45 nGy/h), indoor effective doses (67.37 to 679.77 μSv/y) and indoor excess lifetime cancer risk (0.24 × 10-3 to 2.38 × 10-3). The radon exhalation varied from 1.00 × 10-5 to 15.00 × 10-5 Bq/m2h and the soil properties ranged from 1.11 to 1.66 Mg/m3 (bulk density), 0.10 to 0.65 (soil porosity), 6.00 to 19.00 % (moisture content), 30.21 to 52.00 % (silt), 35.00 to 55.00 % (sand) and 0.01 to 34.79 % (clay). The annual indoor radon concentrations in homes ranged from 23.50 Bq m-3 to 124.90 Bqm-3, the mean seasonal indoor radon levels are 60.54 ± 6.49 Bq/m3 (dry season), 63.85 ± 6.28 Bq/m3 (rainy season) with seasonal radon correction factors varying from 0.51 to 1.55. The results show that, soil properties have influence on the soil radionuclides and indoor radon. The results of Pearson’s linear correlation analysis were in line with principal component analysis and cluster analysis. The findings of this studies are within the recommended limits proposed by International Commission on Radiological Protection, United Nations Scientific Committee on the Effects of Atomic Radiation and World Health Organization. Therefore, soil from these areas is safe and can be used as a construction material without posing any significant radiological threat to the population.