Radiometric and elemental assessment of groundwater from Ifako-Ijaye area in Lagos, Southwestern Nigeria

Abstract

Twenty borehole (BH) and 15 hand-dug wells (HD) water samples were collected from Ifako-Ijaiye for this study. The samples were analysed using NaI (TI) detector for radioactivity and BUCK200 AAS for elemental concentrations. The Effective Dose Rates (EDR) and Excess Lifetime Cancer Risks (ELCR) were calculated from activity concentrations of 40K, 238U and 232Th. The activity and elemental concentrations were statistically correlated. The mean activity concentrations of 40K, 238U and 232Th in the BH water were 8.77±8.40 Bq/L, 1.03±0.19 Bq/L and 0.93±0.15 Bq/L, respectively; and 10.12±0.07 Bq/L, 0.94±0.34 Bq/L and 0.89±0.10 Bq/L, respectively in the HD water. The EDR and ELCR in the study were higher in the infant than either creche or adult. The elemental concentrations in BH water were higher than the World Health Organisation (WHO) recommended limits. The ELCR in the study is higher than the USEPA limit; therefore, drinking untreated water from the area should be discouraged.