title: Modelling of Radiological Health Risks from Gold Mine Tailings in Wonderfonteinspruit Catchment Area, South Africa.
abstract: Mining is one of the major causes of elevation of naturally-occurring radionuclide material (NORM) concentrations on the Earth's surface. The aim of this study was to evaluate the human risk associated with exposure to NORMs in soils from mine tailings around a gold mine. A broad-energy germanium detector was used to measure activity concentrations of these NORMs in 66 soil samples (56 from five mine tailings and 10 from the control area). The RESidual RADioactivity (RESRAD) OFFSITE modeling program (version 3.1) was then used to estimate the radiation doses and the cancer morbidity risk of uranium-238 ((238)U), thorium-232 ((232)Th), and potassium-40 ((40)K) for a hypothetical resident scenario. According to RESRAD prediction, the maximum total effective dose equivalent (TEDE) during 100 years was found to be 0.0315 mSv/year at year 30, while the maximum total excess cancer morbidity risk for all the pathways was 3.04 × 10(-5) at year 15. The US Environmental Protection Agency considers acceptable for regulatory purposes a cancer risk in the range of 10(-6) to 10(-4). Therefore, results obtained from RESRAD OFFSITE code has shown that the health risk from gold mine tailings is within acceptable levels according to international standards.
authors.affiliation: Center for Applied Radiation Science and Technology, North West University (Mafikeng), P.Bag X2046, Mmabatho 2735, South Africa. Manny.Mathuthu@nwu.ac.za.
authors.forename: Manny
authors.initials: M
authors.lastname: Mathuthu
authors.affiliation: Center for Applied Radiation Science and Technology, North West University (Mafikeng), P.Bag X2046, Mmabatho 2735, South Africa. ckamunda@gmail.com.
authors.forename: Caspah
authors.initials: C
authors.lastname: Kamunda
authors.affiliation: iThemba LABS, National Research Foundation, Private Bag X11, WITS 2050, South Africa. madhuku@tlabs.ac.za.
authors.forename: Morgan
authors.initials: M
authors.lastname: Madhuku
mesh_terms: D004784:Environmental Monitoring; D006046:Gold; D006801:Humans; D008906:Mining; D011197:Potassium Radioisotopes / Q000032:analysis; D011834:Radiation Monitoring; D011868:Radioisotopes / Q000009:adverse effects*; D011870:Radiologic Health; D012307:Risk Factors; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D013019:South Africa; D013910:Thorium / Q000032:analysis; D014501:Uranium / Q000032:analysis
chemical_list: D011197:Potassium Radioisotopes; D011868:Radioisotopes; D012987:Soil; D012989:Soil Pollutants; D014501:Uranium; D013910:Thorium; D006046:Gold
keywords: RESRAD-OFFSITE code; activity concentration; cancer morbidity risk; mine tailings; radiation dose; radionuclides