Optimisation of ASE for Determination of Organic Compounds Bound to Particulate Matter

Abstract

Polycyclic aromatic hydrocarbons (PAHs), due to their harmful carcinogenic and mutagenic effects on human health, are significant organic pollutants in the air. Accelerated Solvent Extraction (ASE) at high temperature and pressure is a technique increasingly used to prepare samples for determining organic pollutants in environmental samples. To investigate ASE's efficacy in extracting organic pollutants bound to airborne particulate matter, model samples were prepared by spiking with known concentrations of a certified standard of PAHs. The following variables were optimised: solvent type, number of extraction cycles, extraction temperature, and flushing volume. ASE efficiency was compared with ultrasonic liquid extraction (ULE) using PAH certified reference material and real samples. All samples were analysed by high performance liquid chromatography with fluorescence detection and variable excitation and emission wavelength. Satisfactory efficiency for all PAHs were achieved using a solvent mixture of toluene and cyclohexane (7 : 3, v/v), two extraction cycles at 125 °C, and a flushing volume of 70 % of the cell volume, with recoveries exceeding 97 % for all PAHs except fluoranthene and pyrene (87 %).

Keywords

• pahs
• liquid chromatography
• benzo(a)pyrene
• ultrasonic liquid extraction
• human health