GAMMA RADIOACTIVITY LEVELS AND THEIR RADIOLOGICAL HAZARD INDICES IN SUSPENDED PATICULATE MATTER.....

Aims: The purpose of this study was to determine the concentrations of primordial radionuclides in particulate matter and to assess the possible radiological health risk to the people of Uyo, Nigeria.

The study's design includes sampling dust particle matter by gravity deposition and analysing it using a radiochemical approach.

Place and Time of Study: The research was carried out in the Uyo metropolitan between October 2012 and May 2013.

Methodology: The activity concentration of naturally occurring radionuclides (232Th, 238U, and 40K) in dust particulate samples was determined using a NaI (Tl) gamma ray spectrometer in several selected places of Uyo Metropolis. To determine the origin of radionuclides, the enrichment factor was determined. The radiological indices Absorbed Dose Rate (ADR), Annual Effective Dose (AED), Radium Equivalent Dose Rate (Raeq), External Hazard Index (Hex), and Internal Hazard Index (IHI) were calculated using mathematical models (Hin).

The activity concentrations of the radionuclides in the selected samples were 27.39.71 – 49.916.01 Bqkg-1, 19.309.74 – 35.910.23 Bqkg-1, and 283.854.26 – 834.2128.96 Bqkg-1, respectively for 238U, 232Th, and 40K. The primary anthropogenic contributor to ambient air radiations with moderate enrichment, according to EF values, is 238 K, while 232Th and 40K are crustal in origin. The computed ranges for ADR, AED, Raeq, Hex, and Hin were 54.11 – 82.42Gyh-1, 44.12 – 69.20Svy-1, 93.28 – 141.64Bqkg-1, 0.25 – 0.38Bqkg-1, and 0.33 – 0.52Bqkg-1, respectively. The collected results were analysed in light of the Organization for Economic Cooperation and Development's current International recommended limits. The results showed that the radionuclide activity concentrations were within suggested limits, with the exception of activity of 40K in Uniuyo, Itu Road, and Uruan Street, which slightly exceeded the world recommended threshold of 500Bqkg-1. Raeq, AED, Hex, and Hin were all within the acceptable ranges of 370Bqkg-1, 70Svy-1, 1, and 1.

Conclusion: The findings indicate that there is now no radioactive concern connected with dust particulate in Uyo city. Continuous monitoring of radioactive concentration of dust particles in the vicinity, on the other hand, is recommended.

Please see the link :- https://www.ikprress.org/index.php/JACSI/article/view/3284