What is the cumulative risk of radon exposure particularly greater for?

The cumulative risk of radon exposure is particularly greater for smokers and children due to the combined effects of their heightened susceptibility and increased exposure levels.

Children are more vulnerable to radon because their bodies are still developing, and they have higher rates of cell division. This makes them more susceptible to the harmful effects of radiation from radon decay products, which can lead to lung cancer over their lifetime. Similarly, smokers are significantly at risk since they already have lung tissue that is compromised by tobacco smoke. When combined, the inhalation of radon decay products can amplify the risk of developing lung cancer, as the effects of radon exposure are synergistic with those from smoking.

Other groups mentioned may have specific vulnerabilities, such as pregnant women and infants being sensitive due to developmental factors, or aged individuals who might have pre-existing health issues, but the highest cumulative risk specifically arises from the interaction of smoking and childhood exposure. This makes smokers and children the population with the most significant concern regarding radon exposure.