Natural Radioactivity Measurement and Dose Assessment in Soil Samples from Some Selected Areas of Mali

摘要

This is the first time that a study applies the gamma ray spectroscopy using a high purity germanium to evaluate the terrestrial gamma radiation level by detector in selected regions of Mali. The results reveal that the activity concentrations of naturally occurring 226Ra, 232Th and 40K radionuclides ranges between respectively 17.26 ±1.81 and 105.43 ±10.36;20.41 ±2.52 and 180.85 ±19.69;41.33 ±8.26 and 627.63 ±85.62 Bq⋅kg−1. The measures of radium equivalent activity (Raeq), absorbed dose rates (ADR), annual effective dose rate (AEDR), external hazard index (Hex), internal hazard index (Hin) and excess lifetime cancer risk (ELCR) were evaluated. Some of the obtained values exceed the recommended safe levels. Further studies are necessary to constitute a baseline reference data about the terrestrial radiation in Mali.