42. 氡及其衰变产品是肺癌的致癌物质，这早已得到证实。但是，由于吸入氡及其衰败产品而进入其他器官和组织的剂量非常少，通常情况下，至少低于进入肺的剂量。此外，流行病学数据很少有证据表明除肺癌所致死亡以外的其他死亡率风险增加。
42. Radon and its decay products are well established as lung carcinogens. However, the doses to other organs and tissues arising from the inhalation of radon and its decay products are quite small, usually at least an order of magnitude smaller than the doses to the lung. Moreover, epidemiological data provide little evidence for increased risks of mortality other than for that due to lung cancer.