This study was focused on the fractionation of the mixture of polycyclic aromatic hydrocarbons and their derivatives, especially nitrated derivatives, found in soil and roadside dust extracts. Liquid chromatography with an open silica gel bed was used. Different volumes of hexane, hexane:dichloromethane (1:1 and 4:1, v/v), dichloromethane and methanol were used for the elution of individual fractions. Increasing volume of hexane was not sufficient for complete separation of a slightly polar fraction from the aromatic fraction. Increasing content of hexane in the elution mixture improved the separation of the group of target compounds. Soil and roadside dust extracts were obtained by using a pressurised solvent extractor with dichloromethane as the extraction solvent. Detection limits of the method ranged from 50 to 220 pg of individual nitro-PAHs injected into gas chromatograph. A significant amount of 1-nitropyrene was detected in the real samples collected close to the Brno centre.
silica gel; fractionation; PAHs; nitro-PAHs; soil; roadside dust
