Radiological Safety Assessment of Tailings Extracted from Kaolin Mining Sites in Katsina State

Abstract

This research was carried out to sufficiently justify the recent increased awareness and concern for the potential hazards associated NORMs in the environment of the research around Kankara and Dutsin-ma Kaolin mining sites Katsina State; Nine (09) Kaolin samples were collected randomly from the mining sites for the study. The radioactivity analysis was done experimentally using NaI(TI) gamma spectrometer at Center for energy research and training, Ahmadu Bello University Zaria. The health hazards were evaluated using numerous radiological, Statistical and USEPA models. The overall hazard index (HI) was found to be 1.496609 for children found in third sampling point of Yar-goje are; it is the only possibility of a children to be affected while 0.799486 for adults, this value was below the USEPA threshold limit for non-carcinogenic risks of 1.0 indicating that the exposed population ages are unlikely to experience any adverse non-carcinogenic risks. The radiological parameters obtained are 226Ra (238U), 232Th and 40K of a NORMs with activity concentration of is 100.889, 0.129 and 224.040 (Bqkg-1) in the soil samples, at the studied area. Absorbed frequency in air measured in nGy/h by one-meter directly above the crushed, was considered, since the forbidding radioactivity concentrations is obtained as 77.575 while the total annual effective dose (AED) in mSv/y had average value of 0.099 in soil. The values obtained for external and internal radiological hazard indices Hext and Hint are 0.471 and 0.741 in soil; which were lower than the UNSCEAR suggested boundary limit of unity. Lastly, the overall excess lifetime cancer menace owed to NORMs, stood as 5.63E-06 and 4.15E-06 for whole populations indicating that (a maximum of 6 people/1 million may be affected) for adults while (a maximum of 4 people /1 million may be affected) for children. These values were within the USEPA threshold of 1E-04.