【作者】 周斌；

【导师】 赵彬；

【作者基本信息】 清华大学 ， 土木工程， 2013， 硕士

【摘要】 近30年来，我国城乡居民的肺癌发病率迅速增长，而作为一种已知的重要致癌物质，多环芳烃在我国室内外空气中的污染十分严重。合理地评估由于多环芳烃呼吸暴露导致的肺癌风险，对评价其污染现状以及制定有效的控制措施都至关重要。本文以建立适合进行多环芳烃人群呼吸暴露评价的模型为主要目标，首先在传统污染物健康效应的时间序列研究中尝试引入暴露系数的概念，显示出室内环境及通风因素对于人员污染物暴露的重要影响。接着，通过将前述模型进行细化加深，着力建立了可用于估计多环芳烃室内空气污染浓度分布、人群呼吸暴露量及肺癌风险定量评估的模型。该模型以二维蒙特卡洛方法为框架，以室内多环芳烃污染浓度的预测模型为内核，实现了人群多环芳烃呼吸暴露量及相关肺癌风险的定量模拟评估。室内多环芳烃污染浓度预测模型经过与已有的实验数据进行了验证和评估，显示出了较好的准确性；而蒙特卡洛的模拟框架也在实验中显示出其在室内污染物浓度预测中的有效性。然后，本研究以2006年的北京地区为例，收集了与人群呼吸暴露计算相关的大量参数，包括人口统计信息、气象参数、室外大气多环芳烃、颗粒物污染浓度、主要室内污染源的存在比例及其散发强度等。在此模型和数据的基础之上，本文分析评估了北京地区的多环芳烃人群呼吸暴露及相关肺癌风险，发现北京地区人群因多环芳烃暴露而导致的肺癌风险人群归因百分比为2.99%（95%CI：1.71%-4.26%），并解析了人群暴露的不同污染来源、不同暴露地点的模式特征，发现城市人群中占主导作用的暴露为室外带入室内的污染引起的暴露，而在农村人群中有室内污染直接导致的室内暴露也起到了不容忽视的作用。此模型还被应用于定量评价比较各种污染防控措施的效果，通过对5类13种不同的防控措施在降低室内多环芳烃浓度、减小年暴露量和降低肺癌风险方面的效果进行分析，显示出模型良好的应用前景。更多还原

【Abstract】 The incidence and mortality of lung cancer have been increasing rapidly in the lastthree decades in China. Polycylic aromatic hydrocarbons (PAHs) are a knowncarcinogen in ambient air and their pollution in China’s atmosphere is very heavy. Toquantitatively assess the lung cancer risk due to PAH inhalation exposure is veryimportant to address the pollution in China and to make effective control strategies.The core of this study was to establish suitable model for population inhalationexposure to PAHs. As the first step, the concept of exposure coefficient was introducedto explain the geographical heterogeneity found in China Air Pollution and HealthEffects Study. The results showed significant correlation between the PM10exposurecoefficients and mortality coefficients, underscoring the importance of indoorenvironment and ventilation condition on exposure estimates. This concept was furtherdeveloped into a population exposure model for PAHs. This model used a2-stageMonte Carlo simulation framework, consisted of a core of indoor PAH concentrationmodel and could quantitatively assess population inhalation exposure to PAHs and theassociated lung cancer risk. The indoor concentration simulation module was evaluatedagainst avalaible experiments and showed good accuracy in model prediction. And theapproapriateness of adopting Monte Carlo framework for indoor concentrationsimulation was validated in an experiment. This study took Beijing region in2006as anexample to demonstrate the use of the proposed model. Parameters related to thiscalculation were collected, including demographical information, meteorlogicalparameters, outdoor PAH and particle concentrations, indoor PAH and particle sourcesand emission factors, etc. The analysis showed that, the popolulation attributablefraction (PAF) of lung cancer rik due to exposure to PAHs in Beijing was2.99%(95%confidence interval:1.75%-4.26%), and the exposure pattern analyses showed thatindoor exposure to outdoor originated PAHs was the dominating exposure pattern forurban residents while indoor sources played an important role in determining ruralresidents’ exposure. This population exposure model was further applied toquantitatively compare and analyze various intervention strategies for PAH inhalationexposure. A total of thirteen strategies in five different categories were assessed in termsof their performance in reducing indoor PAH concentration, controlling annual dose and alleviate lung cancer risk. This analysis showed a good practice of the application of thepopulation exposure model established in this study.更多还原