Radiological assessment of dam water and sediments for natural radioactivity and its overall health detriments
The activity concentrations of natural radionuclides were measured in surface water and sediment samples. The samples were collected from water dam in Abeokuta area in the southwestern Nigeria. The activity concentration was determined using a low-“gamma-spectroscopy. The activity concentration of 40K, 238U and 232Th ranged between 86.55 36.81 - 122.74 57.85 Bq kg-1 , 6.78 2.42 - 10.97 3.75 Bq kg-1 and 5.27 2.65 - 8.19 3.17 Bq kg-1 with a mean of 102.15 ± 60.99 Bq kg-1 , 9.00 ± 3.34 Bq kg-1 and 7.13 ± 2.63 Bq kg-1 respectively for the water samples from the dam, and 118.37 28.73 - 217.91 49.47 Bq kg-1 , 7.98 4.02 - 13.51 5.68 Bq kg-1 and 7.86 2.65 - 11.28 4.24 Bq kg-1 with a mean of 174.69 ± 39.36 Bq kg-1 , 9.94 ± 4.31 Bq kg-1 and 9.12 ± 3.25 Bq kg-1 respectively for sediment samples from the dam. The variability of the values showed the wide disparity in the measured activity concentrations. No artificial gamma emitting radionuclide was detected in the samples. The projected collective health detriment for infants (0-1y), children (7-12y) and adults (>17y) from the ingestion of water from the dam were 28, 38 and 145 persons respectively. However, the chances of radiological hazard to the health of human from radioactivity in the soil were generally low.
Keywords: Radionuclides, Activity Concentration, Water, Sediments, Health Detriment, Radiological Hazard.