Inhalation of radon alpha particles increases the risk of which health effect?

• A. Beta particles
• B. Gamma rays
• C. Alpha particles
• D. Neutrons

Answer: (C)

Radon inside the lungs decays and its short-lived progeny emit alpha radiation directly onto the airway lining. Alpha particles are highly ionizing and deposit most of their energy over a very short distance, so the damage is concentrated in the bronchial epithelium where the radon progeny reside. This intense, localized energy deposition damages DNA and increases the risk of developing lung cancer. Other radiation types listed don’t deposit energy in the lung tissue in the same way from inhaled radon, and neutrons aren’t produced by radon decay.