ASSESSMENT OF PUBLIC EXPOSURE TO IONIZING RADIATIONARISING FROM MINING ACTIVITIES IN AZARA TOWN NASARAWA STATE, NIGERIA

It was observed by United Nation Scientific Committee on the Effects of Atomic Radiation and International Commission on Radiation Protection that there could be some exposure in some environment which would require regulatory control but is not really considered. In recent years there has been rampant dumping of mining tailings within Azara, a town surrounded by hundreds of mining sites, and mining is the major activity of the inhabitants. The people of Azara are faced with risks of radiation exposures due to the presence of naturally occurring radioactive materials (NORM) in the earth and in the products, by-products, and wastes derived from mining operations. The objective of this work is to assess the exposure level in Azara town due to mining activities and dumping of tailings within the town. Gamma dose rates of ten Areas in Azara, a town in southern Nasarawa state, were measured in situ using an environmental radiation detector. The exposure levels of ten different areas were measured I metre above the ground using an inspector alert nuclear radiation meter and it was found that the annual dose rate ranges from (0.50 ± 0.19 mSv/h) to (0.90 ± 0.67 mSv/h). The absorbed dose rate were converted to annual effective dose rate in order to compare it with the public exposure limits by ICRP, it was found that the annual effect dose rate is between 0.76 tnSv/yr -1.10 mSv/yr. The average absorbed dose rate for the ten areas was found to be 0.66±0.3ImSv/hr lm above the ground level while the average annual effective dose rates were found to be 0.81 mSv/yr which is below the public exposure limits and may not necessarily result to any hazard. It was established that Gindin Rimi has the highest annual effective dose rate of about1.10 mSv/yr which is very high compare to public exposure limits by ICRP, people leaving in this area are bound to face long tune radiation health effect. People living in areas identified with high background radiation levels in this study should therefore be informed of the potential radiation related health problems, while government should also do more to stop the common practice of using mine wastes for foundation fillings and block construction because of the radiological implications.