【作者】 魏玉梅；

【导师】 吴祖成； 张清宇；

【作者基本信息】 浙江大学 ， 环境工程， 2011， 博士

【摘要】 二甲基甲酰胺(N, N-Dimethylformamide,DMF)是一种对人体消化系统、呼吸系统、生殖系统等全身多个系统产生毒作用的有毒有害污染物,甚至可能对人体产生致癌效应。我国作为DMF使用量最大的国家,存在相当大数量的DMF暴露人群。且随着DMF使用量的不断增加,暴露人群仍将持续增加,受到的健康风险也越来越大。而DMF作为一种非常规污染物,并无环境空气监测站点,可供参考的环境空气中DMF浓度数据非常有限。因此,我国环境空气中DMF浓度到底达到何种水平,DMF暴露对人群健康危害的程度如何,是否与某些疾病发病有所关联,对人群的健康风险如何,至今仍尚不清楚,从而也无法采取有效措施降低人群暴露的健康风险。为解决上述问题,本研究基于区域内合成革企业基本情况现状调查和污染源监测数据建立的排放清单,采用大气扩散模型模拟污染物细网格时空分布的方法,在对模型的本地化适应性进行调整后,通过模拟获得了研究区域1999～2008年DMF年均浓度及日均浓度变化趋势。提出基于地理信息系统(Geographic Information System,GIS)的人口和活动加权人群暴露评估方法,调查了研究区域常住人口GIS分布,并对1289名当地居民进行了出行特征调查,基于污染物浓度时空分布和人群出行特征,计算了研究区域1999～2008年100m×100m人群DMF年均及日均暴露浓度分布,并计算了不同职业人群的DMF暴露水平。采用多因素Logistic回归分析法,在控制混杂因素的基础上,研究了DMF暴露对人群肝病、呼吸系统疾病、消化系统疾病、心血管疾病及癌症住院发生等的影响。采用基于泊松回归的半参数广义相加模型,在控制混杂因素的基础上,建立了DMF与呼吸系统疾病、消化系统疾病、心血管疾病及总疾病(分性别)每日入院人数的暴露反应关系。通过健康风险评估,获得了研究区域1999～2008年基于GIS的DMF人群暴露的风险系数变化趋势及不同职业人群的DMF暴露风险,并研究了暴露风险与DMF暴露浓度与环境空气浓度的相关性,提出了风险阈值下DMF环境空气浓度及暴露浓度的标准建议。本论文所取得的主要研究成果及结论如下：(1)1999～2008年DMF年均浓度范围为0.09 mg/m3-0.85 mg/m3,日均浓度范围在0.003mg/m3-4.61 mg/m3之间。随着生产线数量的增加,DMF浓度自1999年逐渐增大,至2002达到最大值。此后由于污染物治理设施投入,DMF排放呈逐年下降趋势,至2008年最小无组织排放对环境空气中DMF浓度的贡献率最大。对无组织排放DMF进行收集处理,是降低环境空气中DMF浓度的有效途径。利用大气扩散模型模拟获得污染物浓度时空分布的方法是可靠的,弥补了由于缺乏监测浓度而无法进行人群暴露水平评估的问题,且能够获得长期连续的污染物浓度时空变化趋势,为人群暴露水平评估提供详细的污染物浓度分布。(2)1999～2008年人群DMF暴露浓度平均值在0.09 mg/m3-0.88mg/m3之间,高密度人口主要集中在DMF低浓度区域。不同职业人群2008年DMF年均暴露浓度在0.034～0.082mg/m3之间。受居住地停留时间较长及环境空气中高DMF浓度的影响,退休人员和农民的暴露浓度最高,为DMF高暴露人群。出行特征对人群暴露水平影响较大,考虑出行特征的暴露浓度更能真实反映污染物对人群健康的影响。(3)长期暴露于DMF环境中,将使人群肝病、呼吸系统、消化系统疾病、心血管疾病和癌症住院发生的危险性增加,其中对消化系统疾病和心血管疾病的影响最大,比值比(Odds ratio,OR)和95%置信区间(confidence interval,CI)分别为1.272(1.062～1.523)和1.578(1.205～2.066)。DMF短期暴露下,浓度每增加一个四分位间距(interquartile range,IQR)时,人群呼吸系统疾病、消化系统疾病、心血管疾病、总疾病(总人数)、总疾病(男性)和总疾病(女性)每日入院人数增加的百分比(95%CI)分别为9.3%(1.17%～18.06%),10.62%(4.04%～17.62%),4.44%(-5.2%～15.07%),7.11%(4.18%～10.12%),4.33%(0.28%-8.54%)和9.73%(5.69%～13.94%)。不同疾病类别中,DMF暴露对呼吸系统和消化系统疾病入院对的危险性较高,对女性因病入院的影响高于男性。DMF暴露对人群健康的影响可能与性别存在关系,可能不同性别人群体内DMF解毒机理有所不同。(4)1999～2008年,DMF暴露风险系数的平均值在2.12～20.21之间。其中,2008年人群DMF暴露的总风险系数在0.038～14.78之间,平均风险系数为2.076,区域人群总体处于DMF暴露中风险水平,环境空气风险为DMF暴露风险的主要来源。不同职业人群DMF暴露风险在0.78-1.89之间,平均值为1.32,其中退休人员DMF暴露的风险最高。(5)当风险处于小于0.1、0.1～10和大于10的的低中高风险时,人群DMF暴露浓度范围分别为0-0.004mg/m3,0.004-0.43mg/m3和大于0.43mg/m3,环境空气中DMF浓度范围分别为0～0.011mg/m3,0.011～0.46mg/m3和大于0.46mg/m3。建议将0.23mg/m3和0.22 mg/m3分别作为DMF环境空气浓度和人群暴露浓度控制限值(风险系数控制在5以下)。更多还原

【Abstract】 N, N-Dimethylformamide (DMF) is a toxic and hazardous pollutant which affects many organ systems such as digestive system, respiratory system and reproductive system, and even may have carcinogenic effects on human body. As the largest DMF consumer worldwide, there are large amounts of DMF exposure population in our country. With the rapid increase of consumption, DMF exposure population keeps on growing and will suffer from more and more serious health risk. As a non-conventional pollutant, there are no monitoring stations of DMF in the urban area. So, limited data on concentration levels of DMF could be obtained. Thus, the questions such as what level of DMF concentrations in the ambient air, what effect of DMF exposure on human health, whether there is relationship between DMFexposure and a certain disease and what health risk it is, still could not be answered. As a result, effective measures could not be taken to reduce human exposure to health risks.To solve these problems, this research established DMF emission inventory based on emission minitoring data and investigation of synthetic leather factory. After adaptability adjusting of the air dispersion model, it was used to simulate spatial and temporal distribution of DMF with fine grids to obtain annual and daily average concentrations of DMF between 1999 and 2008.We proposed GIS-based population and activity weighted exposure assessment method, investigated GIS-based population distribution and selected a total of 1289 household representatives to survey information on movement characteristics. Subsequently, population movement patterns were combined with DMF concentration levels on maps of 100 m×100 m resolution to calculate annual and daily average population exposure of DMF between 1999 and 2008 and DMF population exposure of different occupation groups. Using multifactors logistic regression analysis method, after controlling for confounding factors, we studied DMF exposure effect on liver disease, respiratory disease, digestive disease, cardiovascular disease and cancer. Using poisson regression-based semi-parametric generalized additive model, after controlling for confounding factors, we studied relationship between DMF exposure and daily inpatients of respiratory disease, digestive disease, cardiovascular disease and total disease. We assessed GIS-based helath risk of DMF between 1999 and 2008 and calculated health risk of different occupation groups. Furthermore, we studied relationship between DMF population exposure (DMF concentration) and health risk and proposed standard for DMF concentration and population exposure DMF concentration under the risk threshold.The main results and conclusions of this research are as follows:(1) Between 1999 and 2008, annual average and daily concentration of DMF was in the range of 0.09～0.85 mg/m3 and rang of 0.003 mg/m3-4.61 mg/m3, respectively. With the increase of production lines, DMF concentration increased since 1999 and achieved maximum emission in 2002. Then, with running of pollution control facilities, DMF emission decreased to the minimum value in 2008. Fugitive emission of DMF was the largest contributor of the ambient DMF concentrations. Collect and dispose DMF from fugitive emission is the effective way to reduce DMF ambient concentration. It is reliable to obtain the temporal and spatial concentration distribution of pollutants using air dispersion model. This method resolves the problem that the popupaltion exposure can not be evaluated without the monitoring concentration of pollutant. Using this method can also obtain the long term concentrations of pollutant and provide concentration distribution for population exposure assessment.(2) Annual average concentration of DMF between 1999 and 2008 was in the range of 0.09～0.88mg/m3. High population densities occurred in regions of low DMF pollution. DMF population exposure of different occupation groups was between 0.034 mg/m3 and 0.082 mg/m3. The retired people were the high exposure group because they spent most time at home where DMF concentration was high. There was a substantial impact of movement patterns on the evaluation of population exposure. Population exposure based on movement characteristics could better reflect the impact of pollutants on human health.(3) Long term exposure to DMF would increase the risk of hospitalization of liver disease, respiratory disease, digestive disease, cardiovascular disease and cancer, expecially for digestive and cardiovascular disease, which OR (95%CI) was 1.272 (1.062～1.523) and 1.578 (1.205～2.066), respectively. Short term exposure to DMF, when DMF expocure concentration increases IQR, increase percentage (95%CI) of daily inpatients of respiratory diseases, digestive diseases, cardiovascular disease, total disease (total number, male and female) was 9.3% (1.17%～18.06%),10.62%(4.04%～17.62%),4.44%(-5.2%～15.07%),7.11%(4.18%～10.12%), 4.33%(0.28%～8.54%) and 9.73%(5.69%～13.94%), respectively. The higher risks were found on respiratory diseases and digestive diseases and female (compared with male). There may exsit the difference of DMF exposure impact on different sex group, which may relate with DMF detoxification mechanism.(4) Annual average health risk of DMF between 1999 and 2008 was in the range of 2.12～20.21 mg/m3. DMF human health risk of 2008 was between 0.038 and 14.78 and the average value was 2.076. Population in the study area was exposed to the medium risk level of DMF and the ambient air was the primary source of DMF health risk. DMF health risk of different occupation groups was between 0.038 mg/m3 and 14.78 mg/m3 (average value was 2.076) and indicated that retired people had the highest health risk.(5) If DMF health risk was at the level of lower than 0.1,0.1～10 and higher than 10, then population exposure was in the range of 0-0.004 mg/m3,0.004-0.43mg/m3 and higher than 0.43mg/m3, and DMF ambient concentration was in the range of 0～0.011 mg/m3, 0.011-0.46mg/m3 higher than 0.46mg/m3. We proposed 0.23mg/m3 and 0.22 mg/m3 as the control limits of DMF population exposure and DMF ambient concentration (risk factor was controlled within 5)更多还原