An Assessment of the Radiological Cancer Mortality and Morbidity Risk of Uranium in Rainwater from Selected Areas in Akwa Ibom State, Nigeria

The activity concentrations of uranium in rainwater from selected areas in Akwa Ibom State, Nigeria were measured by the means of a gamma-ray spectrometry using a sodium Iodide Thallium doped NaI (TI) detector. The results obtained were used to calculate human radiological risk over lifetime consumption by the population in the area. The mean activity concentration for Uranium in all the rainwater samples from all the areas was 5.2 + 0.88 Bq. L-1 with a range of 1.2 + 0.21 to 15.00 + 2.92 Bq. L-1. The mass concentration was found to range from 46.74 ± 8.46 to 602.86 ± 117.67 µg. L-1. The radiological risks for cancer mortality risk ranged from 4.3 × 10-5 to 5.6 × 10-4, while that of the morbidity risk ranged from 6.5 × 10-5 to 8.5 × 10-4 these values were found to be low. However, the chemical toxicity was found to vary from 1.28 to 16.51 µg.kg-1.day-1 while the hazard quotient ranges from 2.13 to 27.53 which are higher than the recommended acceptable safe level by various international organizations. Therefore, it is recommended that regular monitoring of rainwater in these areas should be carried out and also, adequate measures such as providing clean and properly treated water to people living in those areas should be taken.