Isotope-labeled substances in analysis of persistent organic pollutants in environmental samples

Ultratrace analysis of persistent organic pollutants (POPs) in environmental samples requires very sophisticated methods for both sample preparation and instrumental analysis. The complex matrix requires a multi-stage procedure. Each stage is a potential source of error, as a consequence of which the final result of analysis could be a source of misinformation rather than information. The individual stages and the procedure as a whole must therefore be validated. There are three tools that can be used for this: standard solutions containing known concentrations of analytes; reference materials; and, standard solutions containing isotope-labeled analytes.Isotope-labeled substances are increasingly important in environmental analysis. Isotope dilution mass spectrometry (IDMS), which yields results of unquestioned precision and accuracy, is gaining favor in analytical laboratories.In this article, we review IDMS applications devoted to analysis of POPs present in samples of different environmental matrices, especially water, soils and sediments.