Trace elements screening methods

Cluster analysis Is used to determine the particle types that occur in an aerosol. These types are used to classify the particles in samples collected from various locations and sampling periods. The results of the sample classifications, together with meteorological data and bulk analytical data from methods such as instrunental neutron activation analysis (INAA). are used to study emission patterns and to screen samples for further study. The classification results are used in factor analysis to characterize spatial and temporal structure and to aid in source attribution. The classification results are also used in mass balance comparisons between ASEM and bulk chemical analyses. Such comparisons allow the combined use of the detailed characterizations of the individual-particle analyses and the trace-element capability of bulk analytical methods. 

ICP-MS has been used for the analysis of many materials, including alloys, steels, nuclear materials, ceramics, superconductors, plastics, polymers, and catalysts. Semiquantitative analysis by ICP-MS is often a convenient method to screen samples for trace elements and impurities. Measurement of impurities can be complicated by sample matrix-dependent degradation of sensitivity, particularly if the samples contain high concentrations of heavy elements that create extensive space-charge-induced ion transmission losses. Matrix matching is complicated by the need for ultrapure materials. 

The production of SWIFT-WFD RMs had a valuable impact in the evaluation of European laboratories performances using both classical and screening methods for four classes of analytes trace elements, major components, PAHs, pesticides. The produced RMs allowed the evaluation of analytical performances at EU level at different levels of concentration, in different matrices (river water, spring water) with different composition. 

A method with LOQ at ppt levels was developed based on LLE followed by GC-AFID for the determination of trace concentrations of nitrobenzene, l-chloro-2-nitrobenzene and synthetic fragrances such as musk xylene (223) and musk ketone (224). The method was applied to study the distribution of these compounds in environmental samples of North Sea waters460. GC with atomic emission detection (AED) has been successfully applied to the determination of nitro musks in human adipose tissues, at ppb concentration levels. A clean-up procedure for nonpolar substances and element-specific detection with AED enabled for the first time target screening analysis for lipophilic nitro aromatic compounds. The lack of sensitivity of AED was compensated by higher concentrations of the extracts... 

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