Radiobiological consequences evaluation following a hypothetical nuclear event based on the radionuclide-to-inventory release ratio.

PURPOSE: This study assesses the radiological impact of radionuclide dispersion for the first four days after a hypothetical nuclear accident scenario, utilizing the HotSpot Health Physics software developed by the Lawrence Livermore National Laboratory (LLNL).

MATERIALS AND

METHODS

A Gaussian plume model was used to estimate the dispersion of I-131 and Cs-137 under various atmospheric conditions.

RESULTS

The study's key findings include an analysis of the Total Effective Dose Equivalent (TEDE) along a simulated contamination plume, highlighting the impact of atmospheric stability on radiation levels. It also assesses the radiobiological risks, noting that young people and women are especially vulnerable, as the risk of thyroid or leukemia may vary by a factor of 104 depending on location and atmospheric stability conditions. The analysis also indicated that the TEDE generated by the inventory release could range from 0.1 to 10 Sv of whole-body exposure within the first 10 km downwind under stable atmospheric conditions.

CONCLUSIONS

Even minor fluctuations in TEDE caused by local atmospheric stability can significantly affect the estimated risks of thyroid cancer and leukemia. This may alter the logistical resources required and the epidemiological methods used to identify and prioritize concerns. Implementing environmental monitoring and strategies such as distributing stable iodine and enforcing dietary restrictions during the initial phases of nuclear emergencies may be guided by risk assessments based on simulations.