Description: Highlights • Higher lipid content in D. cornigera in Cantabrian Sea than in Menorca Channel. • Lipid composition and δ13C values reflected contrasted food captured by corals. • Feeding on phytoplankton and herbivorous grazers by Cantabrian D. cornigera. • Main trophic role of dinoflagellates and invertebrates for Menorca D. cornigera. • High trophic plasticity of D. cornigera. Abstract The cold-water coral (CWC) Dendrophyllia cornigera is widely distributed in areas of both high and low productivity, suggesting a significant trophic plasticity of this coral depending on the food available in the environment. In this study, lipid biomarkers and their isotopic signature were compared in colonies of D. cornigera and sediment from the highly productive Cantabrian Sea (Northeast Atlantic Ocean) and the less productive Menorca Channel (Western Mediterranean Sea). Lipid content and composition in coral tissue clearly reflected the contrasting productivity in the two areas. Cantabrian corals presented higher content in fatty acids (FA), fatty alcohols and sterols than Menorca corals. Energy storage (saturated + mono-unsaturated FA) to structural (poly-unsaturated FA) ratio was higher in Cantabrian than in Menorca corals. The high ΣC20:1 content as well as PUFA(n-3)/PUFA(n-6) ratio suggest that Cantabrian corals mainly feed on phytoplankton and herbivorous grazers. This is also supported by the higher mono-unsaturated fatty alcohols (MUOH) and long chain mono-unsaturated fatty alcohols (LCMUOH) content in Cantabrian compared to Menorca corals. Conversely, higher PUFA(n-6) content in Menorca corals, with the dominance of C22:4(n-6) and C20:4(n-6), as well as the dominance of cholesterol and norC27Δ5,22 among sterols, point to a higher trophic role of dinoflagellates and invertebrates. The observed geographical variability in trophic ecology supports a high trophic plasticity of D. cornigera, which may favour the wide distribution of this CWC in areas with highly contrasted food availability.

Description: Highlights • Investigation on PFAS in seafood was conducted for the first time in North Africa. • Long-chain PFAS were predominant in seafood from the study area. • Among seafood, crustaceans exhibited the highest concentrations of PFAS. • PFOS was the predominant PFAS compound in most marine species. • Human health risks for PFAS exposure via seafood consumption was minimal. Abstract Despite the ubiquity of per- and polyfluorinated alkyl substances (PFAS) in all environmental compartments, little is known about the pollution they cause on the African continent, neither on levels, nor effects. Here we examined the occurrence and levels of 21 legacy and emerging PFAS in 9 marine species (3 fish, 2 crustaceans and 4 mollusks) collected from Bizerte lagoon, Northern Tunisia. Furthermore, assessment of potential human health risks through consumption of contaminated seafood was examined. This is the first study assessing PFAS in Mediterranean coastal areas of North Africa. Twelve out of the 21 targeted PFAS were detected, evidencing the occurrence of PFAS in seafood from North Africa, albeit at low levels. The Ʃ21PFAS concentrations in all seafood samples ranged from 0.202 ng g−1 dry weight (dw) to 2.89 ng g−1 dw, with a mean value of 1.10 ± 0.89 ng g−1 dw. The profiles of PFAS varied significantly among different species, which might be related to their different trophic level, protein content, feeding behaviour and metabolism. Generally, current exposure to PFAS through seafood consumption indicates that it should not be of concern to the local consumers, at least for those PFAS for which information is available.