Abstract:
Natural radioactivity was measured in twenty samples of well water collected from
hand dug wells and drilled wells (boreholes) from Ogun State, Southwestern
Nigeria with a view to provide baseline data on radioactivity level in the area, and
also to estimate the resulting annual effective dose to the inhabitant as a result of
drinking from these well waters.
Using high-resolution gamma spectrometry technique the activity concentrations
of the following radionuclides: 4oK,214Bi,214Pb,226Raand 228Ac were found to be
having a mean activity concentration of 2.98±1.90, 2.21±0.18, 2.10±0.53 ,
. 4.47±1.13 and O.62±O.24Bq r' respectively.
The total annual effective dose due to the ingestion of the natural radionuclides of
4oK,214Si,214Pb,226Raand 228Ac for ages 2-7, ]2-17, and >17yrs were estimated to
be 0.82, 3.89, and 0.89 mSv y -I respectively. These values are found to be above
0.1 mSv y -I of WHO recommended limit for radiological safe drinking water.