Assessment of the various risk factors for lung cancer has found that indoor radon exposure is the primary risk factor for lung cancer in never-smokers and the second ranked risk factor in ever-smokers [1, 2], following tobacco. Radon exposure is responsible for approximately half of the total ionising radiation that the average human being receives in a lifetime (followed in magnitude by medical radiation) and is the largest source of natural ionising radiation [3]. Radon is a colourless, odourless and tasteless gas that comes from the bedrock of the Earth's crust. Radon 222 is the most dangerous and the most common form of radon, from an epidemiological point of view, as 80% of all radon is radon 222. Indoor radon is usually measured in becquerels per cubic metre, and 1 becquerel per cubic metre is equivalent to one nuclear disintegration per second in such a volume. One nuclear disintegration releases one alpha particle. Radon is the second most important risk factor for lung cancer but recommended exposure differs in many countries http://ow.ly/VZ8y30fDdYz

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室内氡的作用水平：同一种肺癌致癌物的不同风险？

对肺癌的各种危险因素的评估发现，室内氡暴露是从不吸烟者肺癌的主要危险因素，在一直吸烟者中排在第二位[1, 2]，仅次于烟草。氡暴露约占人类一生中接受的总电离辐射的一半（其次是医疗辐射），并且是最大的天然电离辐射源 [3]。氡是一种来自地壳基岩的无色、无味和无味的气体。从流行病学的角度来看，氡 222 是最危险和最常见的氡形式，因为所有氡的 80% 是氡 222。室内氡通常以每立方米贝克勒尔为单位，在这样的体积中，每立方米 1 贝克勒尔相当于每秒进行一次核解体。一次核分裂会释放出一个 α 粒子。氡是肺癌的第二大危险因素，但许多国家的推荐暴露量不同 http://ow.ly/VZ8y30fDdYz