Cold vapor atomic fluorescence

For PHg, a variety of different filter methods have been applied, such as Teflon or quartz fiber filters. Before analysis, these filters undergo a wet chemical digestion usually followed by reduction-volatilization of the Hg to Hg(0) and analysis using cold vapor atomic absorbance spectrometry (CVAAS) or cold vapor atomic fluorescence spectrometry (CVAFS). Recently, a collection device based on small qrrartz... 

Bloom NS, Fitzgerald WF. 1988. Determination of volatile mercury species at the picogram level by low temperature gas chromatography with cold-vapor atomic fluorescence detection. Anal Chim Acta 208 151-161. 

DeWild JF, Olson ML, Olund SD. 2002. Determination of methyl mercury by aqueous phase ethylation, followed by gas chromatographic separation with cold vapor atomic fluorescence detection, U.S. Geological Survey Open File Report 01 45, 23 p. 

USEPA] US Environmental Protection Agency. 1996. Method 1631 mercury in water by oxidation, purge and trap, and cold vapor atomic fluorescence (C VAFS). Draft method EPA 821-R-96-012. 

Techniques for analysis of different mercury species in biological samples and abiotic materials include atomic absorption, cold vapor atomic fluorescence spectrometry, gas-liquid chromatography with electron capture detection, and inductively coupled plasma mass spectrometry (Lansens etal. 1991 Schintu etal. 1992 Porcella etal. 1995). Methylmercury concentrations in marine biological tissues are detected at concentrations as low as 10 pg Hg/kg tissue using graphite furnace sample preparation techniques and atomic absorption spectrometry (Schintu et al. 1992). 

Box 21-1 Mercury Analysis by Cold Vapor Atomic Fluorescence... 

Cold vapor atomic fluorescence spectrophotometry for mercury analysis... 

US Environmental Protection Agency, Method 1631 Mercury in Water by Oxidation, Purge and Trap and Cold Vapor Atomic Fluorescence Spectrometry, Office of Water Fact Sheet, EPA-821-F-98-008, [US Environmental Protection Agency, 1998d]. 

In EMEP, ICP-MS is dehned as the reference technique. The exception is mercury, where cold vapor atomic fluorescence spectroscopy (CV-AFS) is chosen. Other techniques may be used, if they are shown to yield results of a quality equivalent to that obtainable with the recommended method. These other methods include graphite furnace atomic absorption spectroscopy (GF-AAS), flame-atomic absorption spectroscopy (F-AAS), and CV-AFS. The choice of technique depends on the detection limits desired. ICP-MS has the lowest detection limit for most elements and is therefore suitable for remote areas. The techniques described in this manual are presented with minimum detection limits. Table 17.2 lists the detection limits for the different methods. 

L. N. Liang, G. B. Jiang, J. G. Liu, J. T. Hu, Speciation analysis of mercury in seafood by using high-performance liquid chromatography on-line coupled with cold-vapor atomic fluorescence spectrometry via a post column microwave digestion, Anal. Chim. Acta, Ml (2003), 131-137. 

Bloom N. (1989) Determination of picogram levels of methylmercury by aqueous phase ethylation, followed by cryogenic gas chromatography with cold vapor atomic fluorescence detection. Can. J. Fish. Aquat. Sci. 46(7), 1131-1140. 

Carpi and Chen (2001) used cold vapor atomic fluorescence spectrometry to measure gaseous elemental Hg inside residential and business dwellings in New York City. Indoor air Hg concentrations averaged 69 ng m (range 6.5 to 523 ng m ) over the 12 sampling locations, of which 11 showed levels of airborne Hg that were elevated compared to outdoor concentrations (range... 

Cold Vapor Atomic Fluorescence Spectrometry (CVAFS)... 

CSV cathodic stripping voltammetry CVAAS cold vapor generation atomic absorption spectrometry (specific for Hg) CVAFS cold vapor atomic fluorescence spectrometry... 

Morita, H., Sugimoto, M. and Shimomura, S. (1990) Selective determination of inorganic and total mercury by cold vapor atomic fluorescence spectrometry coupled with flow injection analysis. Anal. Sci., 6,91-95. 

FIGURE IA2-1 Cold-vapor atomic fluorescence system for ultratrace determinations ol mercury. 

EPA method 16. Iuses oxidation followed by a purge-and-lrap method and cold-vapor atomic fluorescence. Mercury is preconcentrated in the gold coated sand trap by amalgamation. One commercial instrument uses an atomic fluorescence deiection system and claims a working range from <0.05 ppl to - 250 ppb. Iliis method is quite useful for a variety of sample types ranging from seawater to sewage. 

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