ABSTRACT
Radon is the second largest environmental factor inducing lung cancer after smoking. In recent years, with the deeper epidemiological investigation on radon and lung cancer and the further improvement of its methodology, new progress has been made in the research on risk assessment models. This paper reviews the relative risk models of radon-induced lung cancer developed by several international academic organizations or research teams, and briefly introduces the background information on the models and the main factors considered. Based on the indoor radon concentrations in different decades in China, the relative risks of radon-induced lung cancer were estimated and analyzed, together with some suggestions given for more accurate evaluation of lung cancer induced by indoor radon in the future.