Drinking water, trace analysis

In the early part of2004 there was a problem in the UK caused by low levels ofbromate in a branded bottled water. This arose from the presence of low levels of bromide in the water that was then disinfected by treatment with ozone. The bromate ions formed were at levels above the EU and EPA limit of lOpg/l for drinking water. The analysis of this anion at trace levels is demanding and should be left to a specialist laboratory. However, Dionex have published four methods that can be used for the analysis of bromate ions in water and the application notes (81, 101, 136 149) are available from the Dionex website (http /www. dionex. com/)... 

Although simple analytical tests often provide the needed information regarding a water sample, such as the formation and presence of chloroform and other organohaUdes in drinking water, require some very speciali2ed methods of analysis. The separation of trace metals into total and uncomplexed species also requires special sample handling and analysis (12). 

Figure 5.3 Analysis of 100 ml of (a) surface water and (b) drinking water sample spiked with 0.1 pig/ml of microcystins, using column-switching HPLC 1, microcystin-RR 2, microcystin-YR 3, microcystin-LR. Reprinted from Journal of Chromatography A, 848, H. S. Lee et al, On-line trace enrichment for the simultaneous determination of microcystins in aqueous samples using high performance liquid chromatography with diode-array detection , pp 179-184, copyright 1999, with permission from Elsevier Science.

Seubeet a, and Nowak M (1998) Trace analysis of bromate in drinking waters by means of online coupling IC-ICP-MS. Fresenius J Anal Chem 360 777-780. 

Fig. 2.6.1. RP-LC-ESI-MS analysis of flocculation sludge from a Barcelona drinking water treatment plant. Column Cig LiChrolute 250 X 4.6 mm, 5 pm, gradient elution with ACN-water. Upper trace total ion current (TIC), lower traces extracted ion chromatograms for NPEOs, raE0 = 1-5. Inset ESI mass spectrum of NPEO oligomeric mixture.

Determination of Inorganic Oxyhalide Disinfection By-products in Drinking Water using Ion Chromatography with the Addition of a Postcolumn Reagent for Trace Bromate Analysis... 

Environmental Solid and liquid waste Drinking and waste water Priority pollutants Trace analysis Vapor analysis... 

Macroreticular resins, particularly the Amberlite XAD series, have been used extensively to isolate and concentrate trace organic compounds from drinking water (1-8). We have previously reported the use of an XAD cartridge for this purpose and have evaluated the system for the analysis of organophosphorus pesticides (OPs) (4), polynuclear aromatic hydrocarbons (PAHs) (5), phosphate triesters (TAAPs) (6), or-... 

A sample can be preconcentmted by injecting and evaporating multiple aliquots in the graphite furnace prior to analysis.8 To measure traces of As in drinking water, a 30-pL... 

Pb2+-selective electrode with LOD in picomolar range—improvements of many orders of magnitude compared to the ones known at the time [10]. Since then, many ISEs with significantly improved LODs have been reported [11-13] and the theory of the response of ISEs has been redefined 114—161. In 2001, Ceresa et al. reported the application of ISEs for trace level analysis and demonstrated the use of a Pb2+-selective electrode for the analysis of Zurich drinking water [17]. Subsequently, this work has been followed by other examples of application of ISEs for the analysis of environmental samples [18,19]. 

Attempts to optimize polymer-based electrodes for trace analysis have started very recently. Ceresa et al. have reported an ion-selective electrode optimized for the determination of Pb2+ in drinking water. The detection limit was 0.7 ppb (3 x 10 9M) which is somewhat poorer than the best LOD reported so far for Pb2+-selective electrodes [10] but the former was optimized for ruggedness and response time rather than LOD. Nevertheless, the obtained LOD was still adequate for the targeted application since it was about 20-fold lower than the 15 ppb action limit for Pb2+ in drinking water imposed by the USA EPA [79]. The authors used ICPMS as a reference method and obtained excellent correlation for samples of concentration 3nM. It was shown that the calibration procedure required ca. 10 min for stable readings in micromolar to nanomolar concentration levels. Moreover, the authors... 

The ICP-AES instruments may have different configurations with the torch, which may be positioned either horizontally (axial ICP) or vertically (radial ICP). Because of the longer sample residence time in the axial ICP torch, the axial ICP-AES instruments are more sensitive than the radial ones. The state-of-the-art axial ICP-AES instruments (also called the trace ICP) have the high sensitivity that is required for trace element analysis of drinking water. 

The most recent IMEP ILCs on trace elements analysis in wine, rice, and tuna bsh were organized in support of the EC Regulation (466/2001) on upper levels of contaminants in foodstuffs. The IMEP ILCs on water were coordinated in support of the EC Directive 98/83/EC on the quality of drinking water intended for human consumption [18]. In general toxic elements that are strictly regulated in the Directive, such as Cd, Hg, and Pb, are elements under investigation in IMEP, but IMEP also focuses on essential trace elements for human beings like Cu, Se, and Zn in food matrices. 

In the late 1970s HPLC provided an ideal tool for the analysis of pollutants and other environmental contaminants. Techniques were developed for analyzing chlorophenols, pesticide residues, and metabolites in drinking water and soil (parts per trillion) and trace organics in river water and marine sediments, and for monitoring industrial waste water and polynuclear aromatics in air. Techniques were also developed for determining fungicides and their decomposition products and herbicide metabolites in plants and animals. 

A Fischer assay simulates the conversion of oil shale to usable fuels in an above-ground retort. The results of an extensive program of chemical analysis of major and trace elements in spent shale, oil, and water collected from the Fischer assay of a standard oil shale are presented. The concentration of major elements in raw and spent shale can be determined only to 10% in this study. Two criteria show that fluorine and zinc may have been mobilized during the assays. The concentrations of arsenic and selenium in the Fischer assay retort water exceed the maximum permissible concentrations for drinking water. 

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