Sample preparation and analytical techniques for determination of polyaromatic hydrocarbons in soils

Polyaromatic Hydrocarbons [PAHs] have been determined in soil samples for many years. PAHs can arise in the environment from natural sources, oil and petroleum products and combustion processes. Although oil spills influence PAHS concentrations in local areas, the major sources of PAHS are anthropogenic and derived from land based combustion sources. PAHs are globally distributed and the highest concentrations generally occur close to urban centres. Monitoring is essential during the assessment and remediation. It makes further demands on the analytical methods used, since the transformation products are often present in lower concentrations than the parent PAHs and they may be difficult to identify in the complex mixtures found in these samples. It is therefore essential to use powerful analytical tools to fractionate, separate and identify the analyses in the samples. In this paper we review those aspects relating to the analysis and monitoring of PAHs in soils. The aim is to provide an overview of current knowledge, so as to assess the need for future monitoring of PAHs and the present capability for their analysis. Further monitoring of PAHs is justified because of their ubiquity in the environment, their persistence and bioaccumulative properties and their potential for toxicity both to aquatic organisms and human consumers