A simple and efficient method for the determination of pollutant phenols in soils with high levels of organic matter

Abstract

A well-reproducible method to concentrate and determine Environmental Protection Agency (EPA) priority pollutant phenols from soils is developed. Alkaline extraction with 0.1 M NaOH of the phenolic compounds from soil with a high organic content is followed by their concentration in a highly cross-linked polystyrene–divinylbenzene sorbent (Bakerbond SDB-1) and HPLC-UV analysis. Detection limits ranged from 13 to 64 µg kg⁻¹. The effect of the amount of soil and analyte concentration is evaluated and quantitative recoveries are obtained in all the conditions tested. The proposed methodology is validated by comparing the results obtained with those achieved by applying the official EPA Method 3540C (Soxhlet extraction) and by the analysis of a certified reference soil without significant differences being observed with regards to recovery rates, although the new method proves to be faster. The method is applied to the analysis of spiked soils and to the evaluation of the stability of the analytes in these soils.

Keywords:

• phenols
• solid-phase extraction
• soil
• polystyrene–divinylbenzene sorbent

Acknowledgements

This study was part-financed by the MEC (Spanish Ministry of Education and Science), project CTQQ2005-09430-C05-03. Dr Sirvent gratefully acknowledges a research grant awarded by the ‘Generalitat de Catalunya’ (Ref. 2001FI00697).