Modelling Of Radiological Health Hazards in Tailing Soils from Uranium Mines in Erongo Region, Namibia - Abstract
RESRAD-OFFSITE model 4.0 was performed with ICRP 107 based radionuclide transformations transfer factors and ICRP 60 external, inhalation and ingestion dose conversion factors. The cancer morbidity risks modelled for NORM in both mines’ samples had shown that 226Ra was the highest contributor. The RESRAD model included water, plants, soil and atmosphere exposure pathways by external gamma, inhalations and ingestions and
had shown risk factors in descending order as 226Ra > 232Th > 40K > 238U. In RESRAD-OFFSITE model code, the total cancer morbidity risks in descending order were recorded as 3 persons per 1 000 populations (3 x 10-3) by tailings (stockpiles) and surrounding soil samples from mine 1 < 7 – 8 persons per 1 000 populations (7 x 10-3 – 8 x 10-3) by tailings (stockpiles) soil samples in mine 2 < 7 – 9 persons per 1 000 populations (7 x 10-3 – 9 x 10-3) were at risks of developing cancer. This could explicitly prove that the modelled cancer risks in the region was higher than the recommended level of 1 x 10-5 factor for a population and 1x10-3 for a subpopulation documented by the World Health Organization (2011) as well as the world average (0.29 x 10-3) documented by the United Nations Scientific Committee on the Effects of Atomic Radiation.