Is Fucus a suitable biomonitoring organism for polycyclic aromatic hydrocarbon contamination? A study from the Faroe Islands

To evaluate seaweed as a biomonitoring organism, Fucus was sampled in the Faroe Islands. Nineteen PAHs, including the EPA 16, and four groups of alkylated PAHs were quantified using GC–MS analysis of extracts obtained using a modified QuEchERS method with ultrasonication in acetonitrile, back-extraction into hexane, and Florisil® cleanup. Samples from the harbor of Tórshavn collected at high tide were the most polluted with PAH concentrations between 1.3 × 10² and 1.7 × 10² ng/g wet weight. All samples contained a factor 10 higher concentrations of alkylated PAHs compared to their parent compounds. These results suggest that Fucus might be suitable as a biomonitoring organism for PAH pollution. Differences between samples collected in close proximity and on different days were observed (same range of RSD 14–120% and 60–102%, respectively), suggesting that water exchange, tide levels, and direct exposure to surface diesel pollution have a strong influence on pollutant uptake in Fucus. The findings stress the need for further evaluation of the sampling strategy.