Investigation of Radium Contents and Radon Exhalation Rates in Soil Samples in Menge District, Ethiopia

摘要

Radon has been recognized as one of the major contributor to the natural radiation and health hazards in the human dwellings, working places and mining areas. Even lung cancer is expected if it is present in enhanced levels beyond maximum permissible limit. We have studied radium contents and radon exhalation (both mass and surface) rates in Menge mining and non-mining areas of the Benishangul Gumuz region in Western Ethiopia using the sealed Can technique and LR-115 type II plastic nuclear track detectors. Fifteen soil samples were collected over the study area according to the fraction of the populations and mining and non-mining areas. It is found that the values of radium contents vary from 1.20 to 3.94 Bq.kg~(-1) with an average value 2.44 Bq.kg~(-1). It is also found that gold mining areas have had relatively higher radium contents as compared to the other samples which are collected from non-mining areas. And radon exhalation study is important for understanding the relative contribution of the material to the total radon concentration found inside the study area. The radon mass and surface exhalation rates for the studied samples had the mean values of 2.1610~(-6) Bq.kg~(-1).d~(-1) and 1.1410~(-4) Bq.m~(-2).d~(-1) respectively.