Terrestrial gamma radiation level and the activity concentrations of natural radionuclides in crude oil-impacted soils of Okuregbe Creek, Nigeria

Abstract

Abstract This study evaluated the terrestrial gamma radiation and the activity concentrations of natural radionuclide ( 40 K, 226 Ra and 232 Th) in crude oil-impacted soils of Okuregbe Creek, Ogoniland, Nigeria, using both in-situ and laboratory measurements. A GQ GMC-500/GMC-500 + digital Geiger-Müller counter was used for in-situ measurements, and a CsI(Tl) detector was used for the gamma spectrometry. The activity concentration 40 K in the crude oil impacted area varied between 218.2 and 477.3 Bq/kg, while 226 Ra and 232 Th ranged from 23.4 to 52.3 Bq/kg, and 24.9 to 87.0 Bq/kg, respectively. Although the oil-impacted soils show higher mean activity concentrations for 226 Ra and 232 Th than the control soils, the measured ranges remained largely comparable with worldwide soil radioactivity reported by UNSCEAR. The estimated mean absorbed dose rate in the oil-spilled creek was higher than the control but remained below the global baseline. Similarly, all the calculated radiological hazard parameters fall within their international permissible safety limits. The results of this study show that while petroleum exploitation has technologically enhanced naturally occurring radioactive materials in Okuregbe Creek, the soils currently pose no immediate acute radiological hazard to the local population. Continuous environmental monitoring is recommended to safeguard against long-term ecological bioaccumulation.

The authors' abstract, as published at the source. Scientific Reports, 2026 · DOI ↗