Natural Radioactivity Levels in Groundwater Sources and Their Health Impact Assessment on the Consumers

Groundwater is one of the significant sources of drinkable water in our society today. Groundwater samples were collected from various locations and then prepared for a coaxial high-purity germanium (HPGe) detector for analysis. These studies measured the activity of 232-Th, 226-Ra, and 40-K in groundwater sources; then estimated the total annual effective radiation dose in groundwater and the lifetime cancer risk to the populace. The results show that the mean activity of 40-K from Egbeda, Ipaja, and Ije Ododo is 2.534, 1.713, and 1.931 Bq/l, respectively. These values were higher than the mean activity of 232-Th, which was 0.342, 0.364, and 0.402 Bq/l for Egbeda, Ipaja, and Ije Ododo, respectively. The mean activity of 226-Ra from Egbeda, Ipaja, and Ije Ododo is 1.191, 0.735, and 0.490 Bq/l, respectively. Hence, the mean total effective doses from Ipaja are 0.218 μSv/year for adults, 0.246 μSv/year for children, and 0.219 μSv/year for infants. In adults, the annual effective radiation doses were highest in EG1, with a value of 0.429 μSv/year, and EG4 had a value of 0.455 μSv/year. PA4 had a value of 0.344 μSv/year, and the lowest was recorded from JE3, with a value of 0.076 μSv/year. The obtained values were lower in Ipaja and Ije Ododo; this may not pose any significant health problems. Samples from Egbeda show significantly higher values of annual effective dose and may pose health problems for the consumers in the long term due to bioaccumulation