宣威肺癌高发区燃煤排放颗粒物中铁的价态及其氧化性  

Species of Iron in Size-resolved Particle Emitted from Xuanwei Coal Combustion and Their Oxidative Potential

作　　者：王强翔[1] 谭正莹 赵慧[1] 李继华 田林玮[3] 王青躍 米持真一 吕森林[1] 

机构地区：[1]上海大学环境与化学工程学院,上海200444 [2]云南曲靖疾病预防控制中心,曲靖555000 [3]香港大学公共卫生学院 [4]琦玉大学理工学研究科 [5]琦玉环境科学国际研究中心

出　　处：《环境科学》2017年第6期2273-2279,共7页Environmental Science

基　　金：国家自然科学基金项目(21477073;41273127;41272180);NSFC-JSPS合作交流项目(41511140096)

摘　　要：云南宣威地区的高肺癌死亡率被认为是与居民室内燃烧烟煤有关.为探明宣威地区高肺癌死亡率的原因,在宣威4个不同区域采集了原煤样品并在室内利用一套自行设计的烟气采集装置对所采集的原煤样品模拟当地燃烧条件进行了燃烧,获取燃煤排放颗粒物样品.使用BCR连续提取法(community bureau of reference,BCR)获取原煤、底灰和燃煤排放颗粒物中铁的赋存形态及分布特征,用高效液相色谱(HPLC)检测燃煤颗粒物在替代肺液(surrogate lung fluid,SLF)中产生·OH水平的变化.结果显示,原煤中存在大量的可氧化态铁,经过燃烧后,飞灰颗粒物中生物可利用的铁(酸可提取态、可还原态、可氧化态)占了很大的比重(46%~78%);燃煤颗粒物24 h所产生·OH的量在不同粒径颗粒物之间存在一定差异,在细粒径段(<1μm、1.1~2μm、2~3.3μm)和粗粒径段(3.3~7μm、>7μm)均表现为·OH的量随粒径减小而增加;同时,燃煤颗粒物中可氧化态Fe的含量与产生·OH能力具有一定的线性相关性(R2=0.32).Many reports have claimed that high lung cancer mortality rate in Xuanwei is associated with the residential coal combustion. Considering iron is the main chemical element in the particles emitted from Xuanwei coal combustion, and especially, reactive oxygen species （ROS） could be generated by redox-active transition metals （TM） such as iron （Fe） in particles, therefore, raw coal samples from 4 coal mines in Xuanwei were sampled, and size-resolved particles emitted from the raw coal samples were collected by using of Andersen Five-stage High Volume Sampler. Species of iron in the raw coal sample, size-resolved particles and bottom ashes were analyzed by BCR sequential extraction method （community bureau of reference, BCR）. The generation potential of·OH free radicals from coal emission particles in the surrogate lung fluid （SLF） solution was measured by using high pressure liquid chromatography （HPLC）. Our results demonstrated that a large fraction of oxidizable Fe could be found in raw coal samples. However, the acid extractable, reducible and oxidizable fractions of Fe in the fly ash particles accounted for a large proportion （46%-78%） in the size-resolved particles after coal combustion. There was difference in levels of·OH free radicals generated from coal emission particles in the SLF for 24 hours among particles with different sizes. The concentration of·OH increased in both fine particles （〈1 μm, 1.1-2 μm, 2-3.3 μm） and coarse particles （3.3-7 μm, 〉7 μm） as the particles size decreased. Linear correlation could be found between the oxidizable fractions of iron and the generation of·OH in particles emitted from coal combustion （R2=0.32）.

关 键 词：肺癌 室内燃煤 铁 BCR连续提取 ·OH 

分 类 号：X513[环境科学与工程—环境工程]