Ionizing Radiation and Pediatric X-ray Assessment in Rivers State, Nigeria

Background and Objective: Pediatric populations in Nigeria are highly radiosensitive, yet comprehensive assessments of background ionizing radiation (BIR) and X-ray exposure are scarce, particularly in sub-Saharan Africa. This study evaluated BIR and pediatric X-ray exposure risks at Rivers State University Teaching Hospital, Nigeria, to identify gaps relative to international safety standards and inform protective measures. Materials and Methods: A dual-phase cross-sectional study was conducted. BIR was measured at 37 hospital sites using calibrated Digilert-200 survey meters with GPS localization. Pediatric dosimetry for 39 patients (aged 3-15 years) undergoing routine X-rays was captured using optically stimulated luminescence dosimeters. Key dosimetric indices entrance surface dose (ESD), absorbed dose, effective dose, and excess lifetime cancer risk (ELCR) were calculated using ICRP coefficients and Monte Carlo derived factors. Data were analyzed using SPSS v25; Pearson’s correlation assessed relationships between kVp, mAs, FSD, and ESD, compared with IAEA pediatric DRLs, with p<0.05 considered significant. Results: The BIR exceeded ICRP thresholds in 55% of indoor sites, peaking at 0.020±0.002 mR/hr near radioactive waste storage. Outdoor levels ranged from 0.008±0.002 to 0.020±0.002 mR/hr (mean 0.011±0.003 mR/hr). Pediatric ESDs varied by procedure: Chest X-rays averaged 0.009 mGy, skull 0.368 mGy, and abdomen 0.371 mGy. Tube voltage correlated strongly with dose (R = 0.73, p<0.05). The ELCR values (0.37×10 to 0.96×10^–3) exceeded the global reference of 0.29×10^–3, indicating elevated lifetime oncogenic risk. Conclusion: This study highlights significant deficiencies in pediatric radiation safety, with environmental hotspots and inconsistent imaging protocols exceeding international benchmarks. Implementing standardized imaging techniques, enhanced shielding, and national pediatric reference levels is urgently needed to reduce long-term health risks in vulnerable populations.