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Polycyclic aromatic hydrocarbons (PAHs) and their oxygenated derivates (O-PAHs) are identified in soils and groundwater of industrialized sites and contribute to the risk for Humans and the Environment. Nevertheless, data are scarce in literature concerning their retention and transfer in soils and no soil - water partition coefficients are available for these compounds. Sorption of two PAHs, fluorene and acenaphthene and two O-PAHs, 9H-fluorenone and dibenzofuran onto two soils with different organic carbon contents was evaluated and compared by determining their sorption isotherms. Effect of ionic strength and liquid to solid ratio, on fluorene and fluorenone sorption was also evaluated. Sorption equilibrium is achieved within less than 24 hr of mixing and linear sorption models best fit the isotherm data. Acenaphthene and dibenzofuran are similarly sorbed onto the soil. K D of fluorene is higher than the one of fluorenone, showing a smaller affinity of fluorenone towards the solid phase. This means that O-PAH could form larger contamination plumes in groundwater than PAHs. Decreasing the L/S ratio from 100 to 50 and 30, increases the sorption of fluorenone onto the soil by 56% and 67% respectively, while the sorption of fluorene is slightly increased. Increasing the ionic strength of the aqueous phase also modifies the sorption of fluorenone, contrary to the sorption of fluorene which is slightly affected., (Copyright © 2021. Published by Elsevier B.V.)

A liquid/liquid extraction method coupled with a GC/MS analysis was optimized to quantify 27 polycyclic aromatic compounds in groundwater from contaminated sites. The aim was to optimize an analytical method to determine Polycyclic Aromatic Hydrocarbons (PAH) and Oxygenated Polycyclic Aromatic Compounds (O-PACs) in water and for apply the method to ground water samples collected from contaminated sites. The analysis takes place in one run, including dissolved as well as colloid and particle-associated compounds. Artificially contaminated waters were prepared with two concentration ranges from 0.01 to 1 µg L−1 and 0.5 to 50 µg L−1. This method proceeds with two main steps. The first step is a liquid/liquid extraction with dichloromethane followed by a concentration procedure. The second step is the injection for separation and quantification in a gas chromatograph coupled with a mass spectrometer. The novelty of this work concerns the control of each step by the introduction of deuterated standards in order in order to estimate the recoveries during the extraction, concentration and injection in the process as well as the possibility of quantifying PAC total concentrations in water. This method leads to very good quantification limits ranging from 1 to 60 ng L−1 for PAHs and from 10 to 1,200 ng L−1 for O-PACs, respectively. High sensitivity has been achieved with some of the PAHs with a good R2 factor higher than 0.994 in the concentration range 0.01 to 1 µ L−1. [ABSTRACT FROM AUTHOR]