Radon In Groundwater Of Iperindo, Osun State, Nigeria: Spatial Distribution, Mining Influence And Public Health Implications.
Asere Adeola Margaret
Physics and Electronics Department, Adekunle Ajasin University, Akungba Akoko, Ondo State, Nigeria
Keywords: Radon, water sources, Iperindo, Rad 7, artisanal mining
Abstract
This study assessed dissolved 222Rn in groundwater and surface-water sources in Iperindo, Atakumosa East Local Government Area, Osun State—an artisanal gold‑mining area—to evaluate spatial patterns and potential health implications. A spatially distributed set of hand-dug wells, boreholes, and streams was sampled using airtight 750 mL bottles; radon was measured with a RAD7 detector coupled to the RAD H₂O aeration accessory and corrected for decay to the sampling time. Results show source‑dependent variability: wells (n=17) ranged 4.22–24.98 Bq·L⁻¹ (mean 13.48 Bq·L⁻¹, SD 6.19), boreholes (n=7) 9.20–18.85 Bq·L⁻¹ (mean 14.60 Bq·L⁻¹, SD 3.43), and streams (n=7) lower and less variable (mean ≈9.36 Bq·L⁻¹). The overall mean was 12.79 Bq·L⁻¹. Although all values are well below the WHO screening reference of 100 Bq·L⁻¹, several wells and boreholes exceed the U.S. EPA guideline of ~11 Bq·L⁻¹. One-way ANOVA and nonparametric considerations indicate source-related patterns consistent with hydrogeological controls, though limited sample sizes reduce statistical power. The study recommends targeted surveillance—prioritizing shallow wells—periodic indoor‑air monitoring where water is used indoors, and simple point‑of‑entry aeration for higher‑activity wells to minimize inhalation and ingestion risks.