Monte Carlo code for microdosimetry of inhaled alpha emitters

Area of Science:

• Radiation physics
• Computational dosimetry
• Pulmonary toxicology

Background:

• Alpha emitters in lung airways pose health risks.
• Accurate energy deposition calculations are vital for risk assessment.
• Existing models need enhancement for complex airway geometries.

Purpose of the Study:

• Develop and validate a Monte Carlo code for local energy deposition by alpha emitters in lung airways.
• Apply the code to assess microdosimetric parameters under various exposure scenarios.
• Adapt the code for realistic airway bifurcation configurations.

Main Methods:

• Developed a Monte Carlo code for alpha emitter energy deposition.
• Validated the code against analytical solutions in cylindrical airway models.
• Applied the code to study uniform and non-uniform contamination by radon progeny.
• Evaluated microdosimetric spectra and average parameters (zp, n, z).

Main Results:

• The Monte Carlo code accurately calculates local energy deposition.
• Validated code performance in cylindrical bronchiolar airways with actinides.
• Assessed microdosimetric parameters for radon progeny in indoor and mine environments.
• Generated microdosimetric spectra and average parameters.

Conclusions:

• The developed Monte Carlo code is a validated tool for alpha emitter dosimetry in lung airways.
• The code provides insights into microdosimetric parameters under different contamination scenarios.
• Ongoing work focuses on applying the code to complex airway bifurcations with realistic particle deposition.