大气PM2.5理化特性对儿童DNA和血管功能的影响

Ambient air fine particles (PM2.5) have significant impact on children’s health. Exposure assessment with single metric especially with PM2.5 mass concentration has brought great uncertainty to health risk evaluation, though those previous studies have, to some extent, identified biological mechanisms linking PM2.5 with oxidative damage and vascular dysfunction in children. Nevertheless, whether the overall underlying mechanisms occur simultaneously and interact with others is unclear. With children as our study subjects, we aim to conduct a panel study during regional complex air pollution period, haze pollution period and control period in Heshan county, the city of Jiangmen within the Pearl River Delta region. This panel study is to provide a more careful evaluation of PM2.5 using different exposure metrics such as mass concentration, number and surface area concentration of different size and chemical composition metrics; to investigate whether oxidative damage of DNA, endothelial dysfunction and blood pressure in children simultaneously respond to changes in PM2.5 concentrations; and to explore the most appropriate metric of PM2.5 that is relevant to health effects; and to provide scientific evidence for the health effects and mechanisms of different physicochemical properties of PM2.5.

大气细颗粒物（PM2.5）是影响儿童健康效应的重要危险因素。以单一度量尤其仅以PM2.5质量浓度为暴露度量应用在健康风险评价上存在着较高的不确定性，虽然一定程度上揭示了PM2.5对儿童氧化应激损伤和血管功能改变的损伤机制，但多种可能的致病机制是否同时发生作用以及相互关系如何，尚未清楚。本项目拟采用panel研究方法，选择儿童作为敏感人群对象，于珠三角江门鹤山市典型的大气复合污染期、区域灰霾期和清洁对照期，通过测定PM2.5质量浓度、不同粒径颗粒物数浓度与表面积浓度、以及化学成分，建立多度量表征的PM2.5暴露评价体系；检测儿童在PM2.5暴露下，机体DNA氧化应激损伤、血管内皮功能紊乱以及血压调节功能变化等功能特征改变及相互关系；应用数理模型甄别和鉴定与急性健康效应关系最为紧密的暴露度量所表征的PM2.5特征，为阐述PM2.5理化特性影响儿童健康的能力及其致病机制提供科学依据。