Baseline Radioactivity and Associated Health Hazards in Padma River Sediments Around the Rooppur Nuclear Power Plant, Bangladesh

The present study provides a comprehensive evaluation of radionuclide activity concentrations and radiological hazards in river sediments collected from both banks of the Padma River in the vicinity of the Rooppur Nuclear Power Plant (RNPP), Bangladesh. Considering the importance of the Padma River as the tertiary cooling water source for RNPP and its extensive use in agriculture, fisheries, and domestic activities, the establishment of baseline radioactivity levels prior to full plant commissioning is significant for environmental and public health.A total of 30 sediment samples were collected from the study area, including 15 samples from the RNPP side and 15 from the opposite bank. The activity concentrations of naturally occurring radionuclides (226Ra, 232Th, and 40K) were determined using gamma-ray spectrometry. The measured activity concentrations ranged from 18 to 30 Bq/kg for 226Ra, 20 to 58 Bq/kg for 232Th, and 330 to 460 Bq/kg for 40K, with corresponding average values of 22 ± 2 Bq/kg, 33 ± 3 Bq/kg, and 389 ± 28 Bq/kg, respectively.Comparison with worldwide average values showed that a small number of samples exceeded the global reference level for 226Ra by up to a maximum of 66%, while several samples showed 40K concentrations exceeding their respective global averages by up to a maximum of 15%. No detectable artificial radionuclides, including 137Cs, were found in the analyzed samples, indicating no significant anthropogenic radioactive contamination. Moreover, all the estimated radiological hazard indices remained within internationally accepted safety limits. These results indicate that the investigated sediments do not pose any significant radiological threat to local residents or the surrounding environment.The present study establishes a robust baseline database for the RNPP region, which will serve as an important scientific reference for future environmental radioactivity monitoring, operational impact evaluation, emergency preparedness, and the implementation of long-term radiation protection and environmental management strategies.