Assessment of Excess Lifetime Cancer Risk from Indoor Radon Exposure in Obio-Akpor Local Government Area, Rivers State, Nigeria.

Abstract

Analysis of indoor radon levels and associated health risk parameters was carried out in residential areas of Obio-Akpor Local Government Area, Rivers State, Nigeria. Indoor radon concentrations were measured using a Corentium Arthings digital radon detector over a monitoring period of 60 days. Geographical coordinates of each sampling location were recorded using a handheld GPS device. A total of ten houses were sampled across three major communities, resulting in 30 sample points. In Eneka, radon concentration ranged from 2 − 30 Bq m⁻³, with an annual effective dose rate ranged from 0.050576 − 0.758640 mSv/yr. The excess lifetime cancer risk (ELCR) over 70 years ranged from 0.177− 2.301. In Rumuokwurshi, radon concentration ranged from 3 − 19 Bq m⁻³, the annual effective dose varied from 0.075864 − 0.480472 mSv/yr, and the ELCR ranged from 0.266− 1.682. In Elimgbu, radon levels ranged from 2 − 102 Bq m⁻³, annual effective dose ranged from 0.05058 − 2.57938 mSv/yr, and ELCR ranged from 0.177 − 3.869. The indoor radon concentrations and dose rates are within the ICRP recommended safety limits, but the calculated ELCR values indicate a need for awareness and mitigation strategies to reduce long-term health risks.