Atmospheric particulates analysis

The methods just noted tell something about the physical characteristics of atmospheric particulate matter but nothing about its chemical composition. One can seek this kind of information for either individual particles or all particles en masse. Analysis of particles en masse involves analysis of a mixture of particles of many different compounds. How much of... 

The chemical composition of particulate pollutants is determined in two forms specific elements, or specific compounds or ions. Knowledge of their chemical composition is useful in determining the sources of airborne particles and in understanding the fate of particles in the atmosphere. Elemental analysis yields results in terms of the individual elements present in a sample such as a given quantity of sulfur, S. From elemental analysis techniques we do not obtain direct information about the chemical form of S in a sample such as sulfate (SO/ ) or sulfide. Two nondestructive techniques used for direct elemental analysis of particulate samples are X-ray fluorescence spectroscopy (XRF) and neutron activation analysis (NAA). 

Scott DR, Hemphill DC, Hoiboke LE, et al. 1976. Atomic absorption and optical emission analysis of NASN atmospheric particulate samples for lead. Environ Sci Technol 9 877-880. 

The importance of surface analysis for evaluating the environmental effects of toxic substances is becoming more apparent as the result of recent work in this field. Chapter 9 describes ESCA, Auger, Ion Microprobe, and SIMS surface analysis techniques for atmospheric particulates. These techniques overcome the obvious limitations of bulk analysis, that is, the wide variability in the physicochemical characteristics of different particles. 

Gaarenstroom, P. D., Perone, S. P. and Moyers, J. L. (1977). "Application of Pattern Recognition and Factor Analysis for Characterization of Atmospheric Particulate Composition in Southwest Desert Atmosphere," Environmental Science... 

The first steps in traditional analysis of the physical and chemical properties of atmospheric particulate matter are sampling, that is, obtaining a representative sample over the desired size range, and collection, that is, separating the particles from air. During sampling and collection, such parameters as humidity, temperature, and particle concentration must be controlled to maintain the sample integrity. 

One of the most successful applications of PIXE has been in the analysis of air pollution particulate matter. Atmospheric particulate matter is typically collected by impaction on a filter paper, which provides an ideal thin sample for PIXE analysis. Another aspect of PIXE that is very important for the analysis of aerosol samples is the ability to analyze a large number of samples in a short time. PIXE analyses typically take less than a minute, and the entire irradiation, counting, sample changing, and analysis procedure can be automated. 

Aras, N.K., Zoller, W.H., Gordon, G.E. and Lutz, G.J. (1973) Instrumental photon activation analysis of atmospheric particulate material. Analytical Chemistry, 45(8), 1481-90. 

Photoelectron spectroscopy (ESCA) and thermal evolved gas analysis (EGA) have been applied to characterize sulfur- and nitrogen-containing species in atmospheric particulate matter. Particulate amines and amides previously identified only by ESCA have been detected by EGA, a bulk method, for the first time. EGA and ESCA results suggest the existence of a sulfate similar to ammonium sulfate but with some of the ammonium ions replaced by a charged organic nitrogen complex. 

Unless particulates are being collected in a grossly polluted atmosphere, large volumes of air must be filtered to give sufficient amounts of material for analysis by flame spectrometry. The filters are then ashed and/or digested prior to analysis. Unused filters are usually used for blank preparation. Pio and Hall18 have published a useful concise review of atmospheric particulate sampling, and a more detailed account has been written by Spurny.19... 

The proposed procedure is applied for the analysis of atmospheric particulate matter collected on filters in an industrial and a residential area. 

Suspended particulate matter can be analyzed after depositing it on high-purity In [641]. With detection limits at the sub-pg/g level data for 53 elements in a 10 mg sample were obtained, which proved to agree by better than a factor of 2 for 34 elements with results from other techniques. Atmospheric particulate matter was subjected to analysis by GD-MS by Schelles and Van Grieken [642]. Air was pumped through a single-orifice impactor stage in which the aerosol was collected on a metal support, which was then used as the cathode in the GD unit. 

Mulik CM, Guyer MF, Semeniuk GM, et al. 1975. A gas liquid chromatographic fluorescent procedure for the analysis of benzo(a)pyrene in 24 hour atmospheric particulate samples. Anal Lett 8 511-524. 

Olmez, 1. (1989) Instrumental Neutron Activation Analy.sis of Atmospheric Particulate Matter, in Lodge, J. P-, Jr. (Ed.), Mclhoifs of Air Sampling and Analysis, 3rd ed., Lewis Publishers, Chelsea, MI. 

Modern bulk analysis methods make possible non-destructive chemical identification, which means that the sample remains intact after the analysis. Such a procedure is provided by electron microprobe or X-ray fluorescence analyses, in which the sample is irradiated by electron beams or X-rays and the elemental composition is determined on the basis of induced characteristic X-ray emissions. These methods have been successfully employed to study both stratospheric (Junge, 1963) and tropospheric (Gillette and Blifford, 1971) aerosol particles. Neutron activation analysis is also widely used to identify the chemical composition of atmospheric particulate matter (e.g. Duceef ai, 1966 Rahn etal., 1971) this is also a non-destructive procedure. 

Barkenbus, B. D., C. S. Mac Dougall, W. H. Griest, and J. E. Caton (1983). Methology for the extraction and analysis of hydrocarbons and carboxylic acids in atmospheric particulate matter. Atmos. Environ. 17, 1537-1543. 

Moreira Vaz, J., Screening direct analysis of PAHS in atmospheric particulate matter with SPME, Talanta, 60, 687-693, 2003. 

Cahill TA, Ashbaugh LL, Baeone JB, Eldeed RA, Eeeney PJ, Elogghini RG, Goodaet Ch, Shaddoan DJ and Wolle FW (1977) Analysis of respirable fractions in atmospheric particulates via sequentied filtration. J Air Pollut Control Assoc 27 675-678. 

Scott DR, Loseke WA, Holboke LE and Thompson RJ (1976) Analysis of atmospheric particulates... 

With modem methods of analysis of atmospheric particulate matter, especially neutron activation, one can determine atmospheric concentrations of vanadium in remote locations. Comparisons of vanadium concentrations with those of other elements in remote areas suggest that much of the observed vanadium orignates from mans activities. Atmospheric vanadium concentrations in most United States cities are less than 20 ngrams/meter, but many cities in the northeastern United States have up to several figrams/meter. A study of Boston shows that residual fuel combustion is the only source of vanadium of sufficient magnitude to produce the concentrations observed. Because of the high sensitivity for its analysis, vanadium can serve as an indicator of wide-scale movement of particulates from this identified anthropogenic source. 

Accurate measurements of the concentrations of trace elements on atmospheric particulates are difiicult enough to make in polluted urban atmospheres but even more so in clean marine or polar atmospheres because of the minute quantities of material that can be collected in a reasonable time. For these measurements, one needs a sensitive analytical technique that is free from interference by other elements present. Recently, the use of lithium-drifted germanium [Ge(Li)] y-ray detectors in neutron activation analysis has greatly improved analytical sensitivities and accuracies for such studies (J). 

Tanaka S, Yasushi N, Sato N, Fukasawa T, Santosa SJ, Yamanaka K, Ootoshi T (1998) Rapid and simultaneous multi-element analysis of atmospheric particulate matter using inductively coupled plasma mass spectrometry with laser ablation sample introduction. J Anal At Spectrom 13 135-140... 

Voorhees et al. ° reported a study of the insoluble carbonaceous material in airborne particulates from vehicular traffic using Py-MS and Py-GC/MS (in addition to TGA, elemental analysis, and radiocarbon analysis). The solvent-soluble organic compounds separated from atmospheric particulate matter (which encompasses a broad spectrum of solid and liquid particles generally ranging in size from several hundred angstroms to several hundred micrometers) had been extensively studied by numerous investigators. Due to its complexity, the insoluble carbonaceous material (ICM) in urban and rural particulate material had not been studied in depth. 

The use of large-volume filter-based samplers for the collection of atmospheric particulates has also been combined with IC for the determination of absorbed metal species. Collected samples are extracted from the filters and desorbed from the particulate matter using acidic solutions prior to analysis by IC combined with elemental selective detection such as ICP-MS. Hexavalent chromium, platinum, and palladium have been determined in this way, as have many other transition and heavy metal ions. 

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