Preliminary probe of radon content in drinking water in Ibadan, south-western Nigeria

Background: It is generally accepted that smokers are more prone to lung cancers, however non-smokers also are at high risk if they are exposed to higher concentration of radon. Radon has been the major source of this alpha particle. Materials and Methods: The use of water in day to day activities has immensely increase the rate of exposure to radon in indoor. Therefore, 42 water samples (30 well and 12 borehole water) use for such domestics activities were systemically collected from different places for radon probing with the aid of an electronic active detector RAD7 produced by Durridge USA. The annual inhalation and ingestion were also estimated from the water samples. Result: After probing the radon in the water samples, the obtained results ranged for well and borehole water samples were 0.08 to 14.8 Bq/l and 0.004 to 5.41 Bq/l respectively. Statistical analysis results confirmed that there is a significant difference between the mean value of radon concentration in different sources of water from both well and borehole, (p=0.000). The estimated inhalation and ingestion doses were lower than the world average reference level. Conclusion: The areas with higher radon concentration in their water samples should take necessary actions to avoid consequences from exposure to higher radon. The total annual effective dose due to inhalation and ingestion were estimated to be 10.0 mu Sv/y for well water and 8.579 mu Sv/y for bore hole water which were lower than the recommended action level of 0.1 mSvy-1 set by WHO.