At present, domestic regarding the health effects of PM2.5 findings consistent with the developed countries. China has between PM2.5 and health-related ecological research and intervention studies, but the lack of standard-setting is most useful for a prospective cohort study. In ecology research pm2.5 detection, in 1993-1997, the two scholars to cooperate in Guangzhou, Wuhan, Lanzhou, Chongqing and other cities to carry out a cross-sectional survey. The results showed that the detection Yuhuatai pm2.5 Which, PM2.5 and children with chronic respiratory disease and lung function decline in the prevalence of linear, positive correlation is much greater than the impact of PM2.5, sulfur dioxide and nitrogen dioxide. Since then customs area under pm2.5 detect Which is good, time-series studies Beijing, Shanghai, Guangzhou and other cities think, PM2.5 exposure does increase the risk of mortality and urban residents. Found that China PM2.5 in large component of health hazards from fossil fuel combustion by-component analysis. Indoor ventilation to indoor ventilation, and outside the higher exchange rate, reduce indoor formaldehyde pollution effect is often evident Xuanwu pm2.5 detection Which is good, but strong sources of formaldehyde, its release rate is volatile gradient or function value of formaldehyde in the air. Ventilation so that the value is reduced, and the release rate increases. Therefore, to increase the indoor air with the outside loop, for low formaldehyde pollution intensity of the situation, for strong pollution control should be used in other ways.