Qian Z, Zhang J, Wei F, Wilson W E, Chapman R S
Joint Graduate Program in Exposure Measurement and Assessment, Rutgers University and University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey 08854, USA.
J Expo Anal Environ Epidemiol. 2001 Sep-Oct;11(5):341-51. doi: 10.1038/sj.jea.7500170.
The field data collection of an air pollution epidemiologic study was carried out from 1993 to 1996 in four Chinese cities of Lanzhou, Chongqing, Wuhan, and Guangzhou. In each city, an urban district and a suburban district were selected. Ambient concentrations of total suspended particles (TSP), size-fractionated particulate matter including PM2.5, PM2.5-10, and PM10, sulfur dioxide (SO2), and oxides of nitrogen (NOx) were measured in these districts. The results indicate the presence of wide inter-city and intra-city gradients in long-term ambient levels of these measured pollutants. Across the eight districts, the 1993-1996 4-year means of TSP, SO2, and NOx ranged from 198 to 659 microg/m3, from 14.6 to 331 microg/m3, and from 31.5 to 239 microg/m3, respectively, and the 1995-1996 2-year means of PM2.5, PM2.5-10, and PM10 ranged from 51.5 to 142 microg/m3, from 29.2 to 107 microg/m3, and from 80.7 to 232 microg/m3, respectively. These pollution ranges substantially extended the upper end of the pollution ranges of previous air pollution epidemiologic studies conducted in North America and Europe. In each district, significant correlations among the measured pollutants were observed for daily concentrations. However, the gradient patterns in long-term means of different pollutants were different across the eight districts. (e.g., PM2.5-10 and TSP were highest in the Lanzhou urban district, PM2.5 and PM10 were highest in the Guangzhou urban district, SO2 was highest in the Chongqing urban district, and NOx was highest in the Guangzhou urban district). In general, seasonal variations were present in the ambient concentrations with high levels often occurring in winter months. The eight districts may be classified into four district clusters based on integrated levels of all measured pollutants. These features of the ambient air pollution have important implications for epidemiological studies and may provide unique opportunities to study exposure-effects relationships in the four Chinese cities.
一项空气污染流行病学研究的现场数据收集工作于1993年至1996年在中国的四个城市——兰州、重庆、武汉和广州开展。在每个城市，选取了一个市区和一个郊区。对这些区域内的总悬浮颗粒物（TSP）、粒径分级颗粒物（包括PM2.5、PM2.5 - 10和PM10）、二氧化硫（SO2）以及氮氧化物（NOx）的环境浓度进行了测量。结果表明，这些测量污染物的长期环境水平在城市间和城市内存在广泛的梯度差异。在这八个区域中，1993 - 1996年4年期间TSP、SO2和NOx的均值分别在198至659微克/立方米、14.6至331微克/立方米以及31.5至239微克/立方米之间，1995 - 1996年2年期间PM2.5、PM2.5 - 10和PM10的均值分别在51.5至142微克/立方米、29.2至107微克/立方米以及80.7至232微克/立方米之间。这些污染范围大大超出了此前在北美和欧洲进行的空气污染流行病学研究的污染范围上限。在每个区域，每日浓度的测量污染物之间均观察到显著相关性。然而，不同污染物长期均值的梯度模式在这八个区域中各不相同。（例如，PM2.5 - 10和TSP在兰州市区最高，PM2.5和PM10在广州市区最高，SO2在重庆市最高，NOx在广州市区最高）。总体而言，环境浓度存在季节性变化，高水平通常出现在冬季月份。根据所有测量污染物的综合水平，这八个区域可分为四个区域组。这些环境空气污染特征对流行病学研究具有重要意义，并可能为研究这四个中国城市的暴露 - 效应关系提供独特机会。
