Equilibrium passive sampling: A novel approach to determine internal tissue concentrations of hydrophobic organic compounds in biota

Equilibrium passive sampling has been applied in numerous abiotic environmental matrices. This approach was extended to biological material. In this work, a passive equilibrium sampling method for the measurement of HOCs in biota was developed as an innovative alternative because classical exhaustive extraction techniques are time-consuming and error-prone. The newly developed method is based on the well-proven SPME fiber method for sediment. Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were used as model lipophilic organic pollutants. Partition coefficients of PAHs and PCBs between the lugworm tissue and the PDMS sampling phase were determined. Polydimethylsiloxane (PDMS) coated glass fibers were directly inserted in homogenized lugworm tissue and glass fibers were analyzed using gas chromatography coupled to mass spectrometry. The method application on lugworms from tidal sand flats near Wilhelmshaven showed that the mean body residue values of PCBs (4 μg g-1) and PAHs (256 μg g-1) were about five times higher for PCBs and more than 22 times higher for PAHs compared to literature data for the North Sea area. This high level of contamination might be a consequence of the oil processing refinery located in direct proximity to the sampling site. This novel approach of applying the SPME method to biota will make biological monitoring more effective and holistic, because seasonally and area-wide changes in all environmental compartments can be recorded quickly.