【正确答案】正确答案： In recent decades, epidemiological data in many countries have shown that the morbidity and mortality rates of many infectious diseases are declining, while the incidence and mortality of cancer are on the rise. A large number of research shows that the incidence of cancer and other diseases are associated with environmental pollution. Positive association between air pollution and the growing problem of fog and haze and lung cancer, has been confirmed by many domestic and foreign experts and authoritative organizations. According to a study, it is suggested that small particles of air can damage the lungs and damage DNA by inflammation, which may be the direct cause of non-smokers suffering from lung cancer. Based on the mortality directly related to the air pollution, the World Health Organization in 2013 classify "outdoor air pollution" as a class of carcinogens, and it is considered so far "the most widely disseminated carcinogens. " As the "culprit" fine particles of the fog haze weather, PM2. 5 is mainly from the car exhaust, industrial production emissions and the construction site and road traffic dust. If we want to effectively control the incidence of lung cancer and mortality, we should make joint efforts of research, health care, environmental protection and other departments to break the existing deadlock. To come up with effective measures has become a top priority.