The Biological Effects Of Ambient Fine Particles On Cardiovascular Risk In City Residents

Ambient particulate matter (PM) is one of an important air pollutants. The effects of PM on human health correlate with the size and chemistry components. The most harmful kind of PM is PM25 whose aerodynamic diameter is less than 2.5um. As the harm of PM25 was widely realized, American published the standard of airborne in 1997,which was 65μg/m3 for 24-hour average concentration and later the standard was adjusted to 35μg/m3 in 2006. China published the environmental quality standard of airborne PM25 in 2012. Researchers have conducted extensive studies on the mechanisms linking cardiovascular toxicity and PM2.5. The possible mechanisms of cardiovascular toxicity are oxidative stress, inflammation, alteration of autonomic nervous function.Our study conducted in Shanghai, where is exposed high concentration of PM25 mainly because of the exhaust gas. The participants in this study is the residents in residential area. The residential area is categorized four groups (≤50m\ 51-100m、101-200m and>200m) according to the distance to major traffic road, the participants are those aged from 45 to 75 non-smokers or quit more than half of a year people, this study is to explore the alteration of autonomic nervous function and biological effects-related to cardiovascular indicators in the general air pollution condition. Meanwhile, this study is to explore the mechanisms linking PM2.5 and cardiovascular disease and establish cardiovascular risk assessment models.In the study, the general data (such as age, sex, height, weight, etc.) was collected by questionnaires. Individual PM2.5 exposure was monitored by AM510; Pulse wave was determined by biological signal processing system, recording low frequency power(LF), high frequency power (HF), LF/HF, arterial augmentation index (AI), etc The indicators of vascular function, oxidative stress, inflammation were determined by Enzyme-linked immunosorbent.The results showed that the individual PM2.5 exposure was associated with the distance from the main traffic roads, The farther to the distance, the lower of the PM2.5 exposure. With the increase of individual PM25, LF, LF/HF, NO, T-SOD, T-AOC and heart rate decreased, but HF, BP, AI, IL-6 and L-10 increased.Meanwhile, in the multiple linear regression, the results found that the increase of individual PM2.5 is associated with the increase of HF,AI,BP,IL-6,IL-6,IL-10 for 0.62,11.48,20.71,21.53,8.47;the decreased of LF/HF,LF,heart rate,NO,T-SOD,T-AOC for 0.32,0.22,0.20,22.02,8.32,29.25.This study suggested that individual PM2.5 was associated with the distance from the major traffic roads; PM2.5 could induce the autonomic nervous dysfunction, change heart rate and heart rate variability, damage endothelial function even lead to vasodilation and systolic function disorders. In addition, PM2.5 could cause oxidative stress and inflammatory response.