Dosimetry calculation of gamma, neutrons, protons, and residual nuclides from radon and progeny alpha interaction with eye, lung, and skin

Alpha particles from radon and its progeny interact with lung, skin, and eye (LSE) tissues, leading to the production of gamma, neutrons, protons, secondary nuclei (SN), and radioactive elements that contribute to cancer risk. Using Geant4 simulations, this study identifies SN such as 12 C and 35 Cl, which are stable, along with radioactive isotopes 26 Al (β + decay, half-life: 7.17 × 10 5 years), 18 F (β + decay, half-life: 109.8 min), and 36 Cl (β − decay, half-life: 3.01 × 10 5 years), all produced through alpha interactions with LSE tissues in the less than 8 MeV energy range. Protons were found to induce body acidosis, posing severe health risks. Geant4 results show the dose rate of SN for 1 Bq/m 3 radon concentration in air around the lung, skin, and eye were 1.24 × 10 −12 , 5.46 × 10 −13 , and 1.35 × 10 −12 Gy/s respectively and the corresponding annual effective doses were 0.09, 0.04, and 0.10 mSv/y respectively. For radon levels exceeding 50 Bq/m 3 , the doses surpass the 5 mSv/y safety limit, increasing health risks. This study highlights the hazards posed by SN and radioactive elements in LSE tissues, particularly for miners and individuals in high-radon environments. It underscores the need for strict radon monitoring and mitigation to reduce exposure and protect public health.