ABSTRACT This review presents a synopsis of recent research into the applications of static secondary ion mass spectrometry (SIMS) to the analysis of environmental samples. The use of a surface analysis technique for environmental sample characterization represents an analytical strategy which is largely complementary to conventional analytical approaches. Conventional analyses are focused on the detection of contaminants in sample bulk. Bulk analysis generally requires separation of the contaminant from the sample, and subsequent detection. It has enjoyed widespread application for a broad range of analytes. However, there are analyte types for which bulk analysis is not optimal. Analytes in this category include those which are ionic, have low volatility, and / or have strong surface adsorptive characteristics. These characteristic, which make separation difficult, are conducive to successful detection using a surface analysis approach. Detailed descriptions of static SIMS investigations conducted in the authors` laboratory are presented. Collectively, these studies chronicle the development of static SIMS instrumentation, optimised for the detection of contaminants on surfaces. The analysis of organophosphate chemicals provides an excellent example of the power of the technique. Initial analyses using a single-stage quadrupole SIMS instrument showed that approximately 0.1 monolayer could be unambiguously detected rapidly and without any sample preparation. The detection limit for these types of analytes could be lowered substantially (to 0.001 monolayer) by using new ion trap SIMS technology: this instrumentation provides an improved duty cycle, selective ion storage, and MS/MS capability. These attributes facilitate sensitive and selective detection of adsorbed contaminants. In addition to the ion trap SIMS research, imaging time-of-flight SIMS (ToF-SIMS) research has shown that adsorption chemistry can be observed at micron-scale spatial resolution, without special surface preparation. An example of inhomogeneous Cs+ adsorption to soil panicles will be reviewed, which showed that Cs+ adsorbs to aluminosilicate-bearing sites, but not to silicate.
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