Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction

Anal Bioanal Chem. 2007 Apr;387(7):2559-67. doi: 10.1007/s00216-006-1110-1. Epub 2007 Feb 1.

Abstract

A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 microg kg(-1) dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatography / methods*
  • Chromatography, High Pressure Liquid
  • Hexanes / chemistry
  • Hydrolysis
  • Hydroxides / chemistry
  • Microwaves
  • Polycyclic Aromatic Hydrocarbons / analysis*
  • Potassium Compounds / chemistry
  • Reproducibility of Results
  • Saponins / chemistry*
  • Sewage
  • Solid Phase Extraction
  • Solvents
  • Spectrometry, Fluorescence / methods

Substances

  • Hexanes
  • Hydroxides
  • Polycyclic Aromatic Hydrocarbons
  • Potassium Compounds
  • Saponins
  • Sewage
  • Solvents
  • n-hexane
  • potassium hydroxide