可吸入颗粒物与人体健康.ppt

可吸入颗粒物与人体健康 inhalable particulate matters and human health quality of air means quality of life,2008 beijing olympics ,“中国正面临十分严峻的环境问题与挑战” 环境污染将成为制约我国社会与经济发展的重要瓶颈,2008 beijing olympics and air pollution,overview of air pollution in the world,ozone particulate matter (颗粒物) carbon monoxide nitrogen oxides sulfur dioxide lead,the most important is particulate matter (pm),six criteria air pollutants,particles suspended in the air are small ,but, small particles pose a big problem, 全球气候 global climate 城市可见度 urban visibility 人体健康 human health,what is pm?,in recent decades, there has been a tendency toward increased summer floods in south china, increased drought in north china. (also world ei nino in the recent years) the black carbon aerosols absorbs sunlight it heats the air and reduces the amount of sunlight reaching the ground. the heated air makes the atmosphere more unstable, creating rising air (convection) which forms clouds and brings rainfall to regions that are heavily polluted. the increase of rising air in southern china is balanced by an increase of sinking air and drying in northern china. when air sinks, clouds and thus, rain, cannot form, creating dry conditions.,颗粒物对气候的影响,particles, clouds, rain,颗粒物对城市可见度的影响,increases in the amount of fine particles in the atmosphere are associated with reductions in visibility, and this is considered to be an indicator of overall air quality.,particles and visibility,haze days (阴霾), air pollution baffled the scientist,global warming or cooling?,马尔代夫或举国搬迁 ,q schiermeier clear skies raise global-warming estimates nature 435 (30 june 2005) 1142-1143,经历了漫长而波折的过程,particles and health,颗粒物有没有害？ 达到什么浓度才有害？ 什么因素导致健康危害？,particles and health,more epidemiological evidence ,收集证据 控诉细颗粒物污染 j kaiser science 307 (2005) 1858-60,尺寸决定：什么部位致病？ 化学组分决定：为什么致病？,but, less toxicological evidence,颗粒物化学组分健康效应,the oxidants (ros) are normally balanced by the antioxidants in the cells 氧化剂与抗氧化剂平衡 excessive ros production could lead to oxidative stress 过多活性氧将导致氧化应激,effect of particle chemical composition,ros cause damage to various cellular structures including lipids, proteins, and nucleic acids (dna),（细胞膜）,（细胞质）,（细胞核）,free radical is the most common type of ros,颗粒物化学组分健康效应,effect of particle chemical composition,time course of increase of cl from the lung (a) and heart (b) of rats exposed to caps (average mass concentration, 300 60 g/m3) or filtered air,颗粒物化学组分健康效应,effect of particle chemical composition,pm induced dose-dependent aec dna-sb formation and dna fragmentation.,dna双链(doule strand),dna碎片,颗粒物化学组分健康效应,effect of particle chemical composition,颗粒物化学组分健康效应,effect of particle chemical composition,颗粒物尺寸作用,颗粒物越细，进入人体呼吸系统部位越深,brain,nerves,blood,head, nerves, blood 0.1 m,105 (2002) 411-414,effect of particle size,smaller is better?,颗粒物致病程度与沉积量有关（dose-health effect） 颗粒药物靶向治疗（targeting aerosol drug delivery）,advantages: targeting drug delivery, non-invasive, faster action,颗粒物在人体呼吸系统传输与沉积,particle transport and deposition,blood (血液循环系统),digestive tract (消化系统),nasopharyngeal (鼻咽),alveolar region (肺泡),tracheobronchial (气管支气管),respiratory system (呼吸系统),sneezing coughing,swallowing,mucociliary clearance,alveolar clearance,dissolved,dissolved,penetrated,dissolved,particle transport and deposition,kleinstreuer et al., annual review of biomedical engineering 10 (2008) 195-220,human lungs,al coates, new england journal of medicine 358 (2008) 304-305,惯性冲击,重力沉降,扩散,particle deposition mechanism,jr wright, nature reviews immunology 5 (2005) 58-68,fast 24 hours,slow days years,纤毛清除,巨噬细胞,传导区,呼吸区,particle clearance,modeling by cfd (计算流体动力学),china is now facing the worst particulate air pollution, the most urgent task is to ,源解析,i = 1,2, m species j = 1,2, n samples k = 1,2, p s