Screening of polycyclic aromatic hydrocarbons in multiple fish species and common whelk in the Faroe Islands using a modified QuEChERS method

This study screened multiple fish species and marine common whelk to evaluate their potential as bioindicators of local pollution by polycyclic aromatic hydrocarbons (PAHs) in the Faroe Islands. Shorthorn sculpins (Myoxocephalus scorpius), Atlantic cod (Gadus morhua), common dab (Limanda limanda), saithe (Pollachius virens), and common whelk (Buccinum undatum), which all populate different tropic levels in the ecosystem were caught around Tórshavn Harbor, Runavík Harbor, Sund, Gamlarætt, and Kirkjubøur. The fish livers and the visceral complex of the common whelk were extracted and analyzed for the 16 PAHs regulated by the U.S. EPA using a modified QuEChERS method and gas chromatography-mass spectrometry. We detected and quantified acenaphthylene, fluorene, anthracene, phenanthrene, fluoranthene, and pyrene in the samples. Of the benthic species, common dab had the highest average ∑PAHs concentration of 11 ± 2 ng/g (ww) tissue. Sculpins had an average ∑PAHs concentration of 5 ± 2 ng/g (ww) liver. The highest concentration of PAHs, regardless of species, was found in Tórshavn with an average ∑PAH concentration of 12 ± 2 ng/g (ww). A principal component analysis showed that benthic species had a higher correlation to high molecular weight PAHs, whereas specific PAH concentration patterns for cods and saithe were less prevalent. Based on these results and the commonly agreed upon bioindicator criteria, the benthic species, common whelks, and sculpins were concluded to be the most suitable indicators of PAH pollution. Proper source identification was not possible due to low sampling size; however, assessing the PAH distribution pattern in the fish species together with the nearby human activities in the area indicate both pyrogenic and petrogenic origin with petrogenic sources being the main contributor.