Radon Concentration Potential and Radiological Health Risks in Benue South Groundwater Sources

Abstract

Abstract The attendant health consequences arising from both the consumption of thawed radon and the inhalation of released radon air and its progenies emanating from the various drinking water sources in our community underscores the relevance of the current research. This pioneering study attempts to evaluate the Rn-222 concentration, the annual committed effective dose (ACED) and the related health risk factors of randomly selected 26 water samples from Apa and Agatu Local Government Areas (LGAs), Benue South, Nigeria. The results of the analysis via liquid scintillation counter, revealed the highest radon values of 13.365±1.065 Bq/l and 18.248±1.740 Bq/l for well water samples higher than the action level of 11.1 Bq/l by USEPA were found in the villages of Apa and Agatu LGAs respectively, while 5.551±0.479 Bq/l lower than the tolerance limit was recorded for the surface water samples. The annual committed effective doses estimated for the different ICRP age groups (3 months, 1 year, 5 years, 10 years, 15 years and above 17 years) were below the acceptable 1 mSv/y baseline but displayed a significant and consistent rise with the age and water consumption frequency of the populace. Excess life cancer risks (ELCR) and the induced lung cancer cases per year per million persons (LCC) for ingestion and inhalation of radon by the inhabitants of the study areas were calculated. ELCRing and ELCRinh mean values of the radionuclide showed different variations below the standard reference line. The average values recorded for the lung cancer cases due to ingestion and inhalation of radon (LCCing) and (LCCinh) and the probability of an individual developing cancer over a lifetime exposure to radioactive element (ELCR) were found to be significantly lower than the suggested 170–230 per year per million persons and 0.29 mSv/y global mean value respectively. This implies that the evaluated radon parameters for ingestion and inhalation in the study areas do not pose any immediate radiological health effects to members of the public but periodic monitoring of the quality of the groundwater sources should be encouraged.