Radon-222 is believed to be the risk factor for?

Ans. d (Lung cancer). (Ref: Robbings pathology, 7th/pg. 285; Harrison's medicine 18th/ch. 89).Ionizing radiation is an established lung carcinogen; increased rates of lung cancer among survivors of the atom bombs dropped on Hiroshima and Nagasaki and large excesses among workers exposed to alpha irradiation from radon in underground uranium mining. Prolonged exposure to low-level radon in homes might impart a risk of lung cancer equal or greater than that of Environmental Tobacco Smokers.Risk Factors for LUNG CANCER:# Cigarette smoking# Occupational exposures to asbestos, arsenic, Beryllium, bischloromethyl ether, hexavalent chromium, mustard gas, nickel and polycyclic aromatic hydrocarbons.# Low fruit and vegetable intake during adulthood (retinoids and carotenoids chemopreventive for lung cancer).# Ionizing radiation.# Prior lung diseases such as chronic bronchitis, emphysema, and tuberculosis.