Geological Determinants of Indoor Radon-222 Levels in Residential Buildings: A Case Study of Cross River State, Southeastern Nigeria

Authors

Keywords:

Building, Cross River State, Geological, Radon-222, Nigeria

Abstract

Indoor Radon-222 concentration levels display variability due to geological and building related factors, but the pattern of variability remains understudied in Nigeria’s tropical South-South region. This study observed indoor Radon-222 in 216 residential buildings in Cross River State, Nigeria using Airthings Corentium Home Radon detector system. The observed mean concentrations of Radon-222 gas varied from 48.226.01 Bq/m3 in Akpabuyo to 319.886.62 Bq/m3 in Obudu. Result of impact of geology on concentration level of indoor radon gas using Kruskal-Wallis statistics produced a mean rank in the order; Precambrian rocks (135.49 Bq/m3) > Cretaceous sediments (111.32 Bq/m3) > Tertiary-Quaternary sediments (21.89 Bq/m3). Medium-large effective size (r = 0.41) was observed. Result of one-way ANOVA test produced the same order; Precambrian rocks (223.46Bq/m3) > Cretaceous sediments (176.22 Bq/m3) > Tertiary-Quaternary sediments (49.44 Bq/m3). Furthermore, the mean radon concentrations for buildings of age 0-5 years, 6-10 years, 11-15 years and > 16 years were 132.12 99.81 Bq/m3, 132.6414.53 Bq/m3, 173.6918.69 Bq/m3 and 211.0612.36 Bq/m3 respectively. Result of Kruskal-Wallis test yields a mean rank in the order; > 16 years (126.77 Bq/m3) >11-15years (104.74 Bq/m3) > 6-10 years (84.58 Bq/m3) > 0-5 years (81.42 Bq/m3). The effect size was small, r = 0.1. Based on World Health Organization recommendation, it is concluded that Cross River State is characterized by low and high radon potential zone with substantial proportion of the region belonging to high risk zone. It is therefore recommended that occupants should ensure adequate ventilation of their living rooms to keep radon gas accumulation in check.

Author Biographies

Atan Obeten Egor

Department of Physics/ Associate Professor

Augustine Agwul Abong

Department of Physics/ Associate Professor

Dimensions

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Published

2026-07-01

How to Cite

Egor, A. O., Ushie, J. A., & Abong, A. A. (2026). Geological Determinants of Indoor Radon-222 Levels in Residential Buildings: A Case Study of Cross River State, Southeastern Nigeria. Nigerian Journal of Physics, 35(3), 274-283. https://doi.org/10.62292/njp.v35i3.2026.597

Issue

Vol. 35 No. 3 (2026): Nigerian Journal of Physics - Vol. 35 No. 3

Section

Articles
Copyright & Licensing

Copyright (c) 2026 Atan Obeten Egor, Joseph A. Ushie, Augustine Agwul Abong

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

How to Cite

Egor, A. O., Ushie, J. A., & Abong, A. A. (2026). Geological Determinants of Indoor Radon-222 Levels in Residential Buildings: A Case Study of Cross River State, Southeastern Nigeria. Nigerian Journal of Physics, 35(3), 274-283. https://doi.org/10.62292/njp.v35i3.2026.597