|
|
 |
| |
|
|
|
Heavy Metals and Naturally Occurring Radionuclides Distribution Risk Assessment in Wetlands in Kampala, Uganda |
|
|
|
PP: 127- 133 |
|
|
|
doi:10.18576/jrna/080204
|
|
|
|
Author(s) |
|
|
|
Emmanuel Muhoozi,
Gertrude Ayugi,
Denis Muyimbwa,
Bosco Oruru,
Henry Kyagulanyi,
Ruth Wabwile,
|
|
|
|
Abstract |
|
|
| This study determined the effect of heavy metal concentration on naturally occurring radioactive material levels within wetlands in Kampala, Uganda. Samples from five wetlands (yams and their accompanying soils) were collected for heavy metal and NORMs analysis using an Atomic Absorption Spectrometer (AAS) and a Na(Tl) gamma ray spectrometer respectively. The study indicated that heavy metals Pb and Hg showed a mean concentration in all the sampled wetlands that were above the maximum acceptable values. The average activities of the radionuclides 232Th and 226Ra obtained in this study were above their maximum world acceptable limits in almost all the wetlands however the average activity of 40K in all the wetlands were below the world acceptable limits. In order to determine the effect of heavy metal loading due to industrial waste disposal to the NORM activity concentrations in these wetlands, Pearson correlation coefficients were determined. These levels of activities however had biological effects to the general population so the dose rates at one metre above the ground and other biological effective dose rates were monitored. The Radium Equivalent (Raeq) values obtained in this study ranged from 71.9 Bqkg −1 to 215.6 Bqkg −1, the external values were in the ranges 0.2 to 0.6 while the internal hazard index values ranged from 0.3 to 0.8. The absorbed dose rate in indoor air ranged from 33.9 nGyh−1 to 94.8 nGyh−1 in the sampled wetlands and the annual effective indoor and outdoor dose rates ranged between 0.166 mSv to 0.593 mSv and 0.044 mSv to 0.115 mSv respectively. |
|
|
|
|
|
|
|
