【作者】 谢昱姝；

【导师】 丁辉； 姜亢；

【作者基本信息】 首都经济贸易大学 ， 劳动卫生与环境卫生学， 2007， 硕士

【摘要】 近年来,大量流行病学研究表明大气颗粒物浓度水平与死亡率、呼吸系统和心血管系统发病率、医院门诊人数等健康效应终点密切相关。然而,对于室内颗粒物暴露水平及其相关健康风险研究较少。由于儿童对环境有害因素的作用更敏感,受环境暴露的影响要比成人脆弱得多;再加之儿童大部分时间都在室内度过,因此开展教室内颗粒物研究尤为必要。基于上述背景,本课题组选取了北京市宣武师范学校附属第一小学的5间教室,使用便携式监测仪和采样仪于秋季（2006年10月23日～2006年11月8日）和冬季（2006年12月25日～2006年12月29日）对教室内外PM₁₀、PM_2.5进行实时连续测量,并同时测定和记录了室内环境参数（温度、相对湿度、CO₂）和教室参数（教室面积、窗户/气窗开启面积、教室内学生数、学生人均占有面积、学生人均占有体积、教室楼层、年级级别）。本研究较为深入地分析了秋冬两季教室内PM₁₀、PM_2.5暴露水平,并运用统计软件定量分析了不同因素对室内PM₁₀、PM_2.5质量浓度的影响,建立了教室内PM₁₀、PM_2.5浓度多元线性回归模型,获得以下主要结论:（1）秋冬两季教室内PM₁₀、PM_2.5暴露水平很高,尤其是秋季PM_2.5（中位数为0.204 mg/m³）。教室内外PM₁₀、PM_2.5质量浓度变化范围很大,其中位数秋季高于冬季,而平均值秋冬两季接近。（2）光散射法所测教室内外PM₁₀、PM_2.5的质量浓度值绝大部分高于滤膜采样-称重法所测的相应值。相对于滤膜采样-称重法而言,光散射法所测室内PM₁₀、PM_2.5的质量浓度日均值分别增加了56.3%、182.2%,室外PM₁₀、PM_2.5的质量浓度日均值分别增加了33.5%、237.8%。（3）当教室通风良好时,相比于室内来源来说,室外大气颗粒物对室内颗粒物质量浓度影响更大,起决定性作用;当教室较为封闭时,由于室内不存在颗粒物室内主要来源——燃料燃烧（烹饪、取暖）和吸烟,室内颗粒物质量浓度将随着学生活动量的变化而变化,其峰值出现在课间休息结束的时刻。（4）教室内PM₁₀、PM_2.5质量浓度受室内相对湿度、温度、CO₂、窗户/气窗开启面积、教室内学生数及学生人均占有体积等因素的影响。其中,秋冬两季教室内PM₁₀、PM_2.5质量浓度均与相对湿度呈正相关（p＜0.001）;秋季教室内PM_2.5质量浓度与CO₂显著负相关（p＜0.01）,而冬季两者则呈正相关（p＜0.05）。（5）秋冬两季教室内PM₁₀、PM_2.5质量浓度无显著性差异（p＞0.05）;不同年级级别对秋冬季教室内PM₁₀、PM_2.5质量浓度有显著性影响（p＜0.05）,随着学生年级的增加,其活动量相对增大,教室内PM₁₀、PM_2.5质量浓度也随之增加;不同楼层教室内PM₁₀、PM_2.5质量浓度在秋季监测期无显著性差异,在冬季监测期其差异具有统计学显著意义。更多还原

【Abstract】 Numerous epidemiological studies in recent years have documented a positive association between ambient particulate concentration level and adverse health outcomes including cardiovascular and respiratory morbidity, mortality and hospital admissions. However, much less is known about indoor particulate matter exposure level and associated health risks. In particular, study on particulate matter in the indoor air of classroom is needed, since children are more susceptible to environmentally hazardous factors and are more vulnerable to health hazards than adults and spend a large part of their time in classrooms.On this background, five classrooms in No.1 Elementary School Affiliated to Xuanwu Normal School were chosen for investigation of indoor air quality. In the autumn measurement period （23rd Oct. 2006 to 8th Nov. 2006） and in the winter measurement period （25th Dec. 2006 to 29th Dec. 2006）, various dust particle fractions (PM₁₀ and PM_2.5) were monitored indoors and outdoors continuously by portable monitors and samplers. Additionally, data on indoor environmental parameters （temperature, relative humidity and carbon dioxide） and classroom characteristic parameters （room area, area of opened windows or louver windows, number of occupants, room area/occupant, room volume/occupant, floor and class level） were collected simultaneously.In this research, exposure to particulate matter in the indoor air of classrooms in autumn and in winter was firstly analyzed in entirety. Applying statistics softwares, the impact of different parameters on particulate matter (PM₁₀ and PM_2.5) mass concentration was then quantitatively analyzed. And the models of indoor particulate matter in two measuring periods were established using the multiple linear regression model. The main conclusions were included as follows:（1） Exposure to PM₁₀ and PM_2.5 in the indoor air of classrooms in autumn and in winter was high, especially that of PM_2.5 in autumn （median: 0.204mg/m³）. And the range of particulate matter mass concentrations was very wide. The median in autumn was higher than that in winter while the means were close in two seasons.（2） The PM₁₀ and PM_2.5 mass concentrations obtained with light scattering method were in general higher than those obtained with the filter-based gravimetric technique. Compared to the filter-based gravimetric method, the light scattering method resulted in an increase in the daily values by 56.3% (PM₁₀, indoor), 182.2% (PM_2.5, indoor), 33.5% (PM₁₀, outdoor) and 237.8% (PM_2.5, outdoor) respectively.（3） When ventilation in classrooms was adequate, compared to indoor sources, ambient particulate concentrations had a significant impact on indoor ones. While inadequate, due to the absence of typical indoor sources of particulate matter, such as cooking, heating and cigarette smoke, the increased concentrations associated with increased physical activity of the pupils and peak values were observed at end of ten-minute breaks.（4） The indoor PM₁₀ and PM_2.5 mass concentrations were related to different parameters including relative humidity, temperature, carbon dioxide, area of opened windows or louver windows, number of occupants and room volume/occupant and so on. For example, a significant positive correlation between relative humidity and PM₁₀ and PM_2.5 mass concentrations was observed in two seasons （p<0.001）; a significant negative correlation between carbon dioxide and PM_2.5 mass concentrations was observed in autumn （p<0.01） while a significant positive correlation between the two parameters was observed in winter （p<0.05）.（5） No marked differences in indoor PM₁₀ and PM_2.5 mass concentrations were observed between autumn and winter （p>0.05）. However, a statistically significant influence of class level on the indoor PM₁₀ and PM_2.5 mass concentrations was apparent in both measuring periods （p<0.05）. The differences in indoor PM₁₀ and PM_2.5 mass concentrations in autumn between Floor 1 and Floor 4 was no statistical significant while there was a statistical significant difference in winter.更多还原