Population doses from terrestrial gamma exposure in areas near to old phosphate mine, Russaifa, Jordan

The exposure rates due to terrestrial gamma radiation were measured in a densely populated area intact and near to an old phosphate mine site. At present, however, the Municipality of Russaifa City used these sites as common public places of animal Zoo and General Park. The absorbed dose rate in air due to U-238 varies from 20.6 to 223.4 nGy h(-1), the dose rate due to Th-232 varies from 5.8 to 17.9 nGy h(-)1. The dose rate due to K-40 is in the range 1.9-13.2 nGy h(-1). The obtained values are comparable to worldwide values. However, the results indicate that the activities of natural radionuclides in samples obtained from the mine areas are higher than those of other sites, consequently, increasing the population dose rate. (C) 2002 Elsevier Science Ltd. All rights reserved.