| Popis: |
Evaluation of indoor radon level and its health risk parameters has been carried out in three communities Azuabie, Trans-Amadi and Nkpogu towns in Port Harcourt, Rivers State, Nigeria. A pocket sized Corentium Arthings digital radon detector meter was used to record the indoor radon concentration levels. The geographical coordinates were recorded using a hand-held geographical positioning system (GPS) for the various sample points. A total of 30 sample points were evaluated, with 10 sample points for each town respectively. The results of the concentration levels showed that for Azuabie (AZ) town, the concentration level varied from 6.660 Bqm-3 to 13.690 Bqm-3 with an average of 10.65±0.95Bqm-3. Nkpogu (NK) town the results of the indoor concentration level ranged from 9.250 Bqm-3 to 18.870 Bqm-3 with an average of 13.32±1.02 Bqm-3, Nkpogu (NK) town, the indoor concentration level ranged from 7.030 Bqm-3 to 20.350 Bqm-3 with an average of 12.25±1.34Bqm-3. The annual absorbed dose for Azuabie, Trans-Amadi and Nkpogu varied as follows, 1.680 mSvy-1 – 3.921 mSvy-1, 2.334 mSvy-1 – 47610 mSvy-1 and 1.774 mSvy-2 – 5.134 mSvy-1 respectively. The annual effect dose rate for the three towns ranged from 0.403 mSvy-1 – 0.941mSvy-1, 0.560 mSvy-1 - 1.143 mSvy-1 and 0.426 mSvy-1 – 1.143mSvy-1. The excess life time cancer risk varied from 1.4117 – 3.294, 1.9607 – 3.999 and 1.4901 – 3.999 respectively. The results of the indoor concentration levels annual and the absorbed dose and the annual effective dose rate are all below the ICRP safe limit. However, the results of the excess life time cancer risk are all higher than the ICRP safe standard limit of 0.029×10-3. |
