University of Exeter, Camborne School of Mines, Penryn, Cornwall TR10 9EZ, United Kingdom.
Environ Sci Technol. 2013 Jun 4;47(11):5570-7. doi: 10.1021/es305025e. Epub 2013 May 15.
This work provides the first automated mineralogical/phase assessment of urban airborne PM10 and a new method for determining particle surface mineralogy (PSM), which is a major control on PM toxicity in the lung. PM10 was analyzed on a TEOM filter (Aug.-Sept. 2006 collection) from the London Air Quality Network Bexley, East London, U.K. A cross-section of the filter was analyzed using a QEMSCAN automated mineralogical analysis system which provided 381,981 points of analysis for 14,525 particles over a period of 9 h 54 min. The method had a detection limit for individual mineral components of 0.05 ppm (by area). Particle shape and mineralogical characteristics were determined for particles in the size ranges PM(10-4), PM(4-2.5), and PM(2.5-0.8). The PM(2.5-0.8) fraction contained 2 orders of magnitude more mineral particles than the PM(10-4) and PM(4-2.5) fractions, however the PM(10-4) fraction forms 94% and 79% of the mineral mass and surface area, respectively. PSM of the PM10 was dominated by gypsum (36%), plagioclase (16%), Na sulphates (8%), and Fe-S-O phases (8%) in the PM(10-2.5), which may be important in explaining the toxicity of the coarse fraction. The wider implications of the study are discussed.
本研究首次实现了对城市大气可吸入颗粒物（PM10）的全自动矿物学/相评估，同时提出了一种新的颗粒物表面矿物学（PSM）测定方法，该方法是控制颗粒物肺部毒性的主要因素。PM10 取自英国伦敦空气质量网络贝克利（Bexley）的 TEOM 滤膜（2006 年 8-9 月采集）。使用 QEMSCAN 全自动矿物分析系统对滤膜的一个横截面进行分析，该系统在 9 小时 54 分钟的时间内对 14525 个颗粒的 381981 个点进行了分析。该方法对单个矿物成分的检测限为 0.05ppm（面积）。对 PM（10-4）、PM（4-2.5）和 PM（2.5-0.8）粒径范围内的颗粒进行了颗粒形状和矿物学特征的测定。PM（2.5-0.8）粒径范围内的颗粒中所含矿物颗粒的数量级比 PM（10-4）和 PM（4-2.5）粒径范围内的颗粒多两个数量级，然而，PM（10-4）粒径范围内的颗粒分别形成了 94%和 79%的矿物质量和表面积。PM10 的 PSM 主要由石膏（36%）、斜长石（16%）、Na 硫酸盐（8%）和 Fe-S-O 相（8%）组成，这可能是解释粗颗粒毒性的重要因素。该研究的更广泛意义也在文中进行了讨论。
