Canepari S, Cardarelli E, Pietrodangelo A, Strincone M
Chemistry Department, University of Rome "La Sapienza", P.le Aldo Moro, 5 00185 Rome, Italy.
Talanta. 2006 May 15;69(3):588-95. doi: 10.1016/j.talanta.2005.10.024. Epub 2005 Nov 28.
Due to the lack of proper standard materials for airborne particulate matter collected on filters, a validation scheme was developed, which is here described, to the aim of testing the application of leaching procedures performing both ions and elemental determinations on real samples of airborne particulate matter collected on filters. The scheme has been developed on a two-step leaching method (extraction in acetate buffer and acid dissolution of residue) previously developed by authors and consists of two series of tests to be run on n pairs of equivalent parallel samples filter-collected. The first series of tests aims to assess on real samples the equivalence between results obtained by the tested procedure with those obtained by the EMEP ions extraction and the EN 12341 standard methods, whereas the second aims to evaluate the reproducibility of analytical results of elemental determination in the leached and dissolved fractions; in the latter case data reliability is also evaluated as a function of the environment-intrinsic variability of real samples. To avoid errors due to sampling differences data from filter pairs were standardized both by gravimetric determination of loaded filters, according to the EN 12341 standard and by the rate SO(4)(2-)/SO(4)(2-) where [SO(4)(2-)] indicate the soluble sulphate concentration in the extract; in the latter case values improved for all elements and in both fractions. Results of equivalence with standard methods and reproducibility tests are evaluated as mean relative percentage differences (Delta%) and percentage elements recoveries (R%). The application of the validation scheme to the two-step leaching method is here discussed for non-volatile ions and for 17 elements detected on 22 pairs of low-volume collected PM(10) samples on Teflon filters.
由于缺乏用于过滤器收集的空气颗粒物的合适标准物质，因此开发了一种验证方案（在此进行描述），目的是测试浸出程序在过滤器收集的空气颗粒物实际样品上进行离子和元素测定的应用。该方案是基于作者先前开发的两步浸出法（在醋酸盐缓冲液中萃取和残留物的酸溶解）制定的，由在n对等效平行的过滤器收集样品上进行的两组测试组成。第一组测试旨在评估在实际样品上，测试程序获得的结果与欧洲监测和评估计划（EMEP）离子萃取法以及EN 12341标准方法获得的结果之间的等效性，而第二组测试旨在评估浸出和溶解部分中元素测定分析结果的重现性；在后一种情况下，还根据实际样品的环境固有变异性评估数据可靠性。为避免因采样差异导致的误差，根据EN 12341标准，通过对加载过滤器进行重量测定以及通过SO(4)(2-)/SO(4)(2-)比率（其中[SO(4)(2-)]表示提取物中可溶性硫酸盐浓度）对过滤器对的数据进行标准化；在后一种情况下，所有元素在两个部分中的值都有所改善。与标准方法的等效性结果和重现性测试结果以平均相对百分比差异（Δ%）和元素回收率百分比（R%）进行评估。本文讨论了验证方案在两步浸出法中对非挥发性离子以及在22对用特氟龙过滤器收集的低体积PM(10)样品上检测到的17种元素的应用。
