Mercury in Barents Sea fish in the Arctic polar night: Species and spatial comparison

Although mercury (Hg) in polar ecosystems has been well-studied, there is little information on Hg the Arctic during low-productivity seasons like night. We quantified concentrations, carbon, and nitrogen stable isotope ratios (δ 13 C δ 15 N) muscle of cod ( Boreogadus saida ), Atlantic Gadus morhua capelin Mallotus villosus) sampled from North-West North-East Barents Sea November–December 2019. concentrations varied between species (14–175 ng/g dw), dependent region, but were well below toxicity threshold for fish health EU-accepted human consumption. Interspecific differences observed only with having highest explained by its larger size, higher trophic position benthopelagic feeding. Spatial than likely due to a combination food web structure exposure. • Winter was low & expected be lower spring bloom. limits consumption EU. Differences Sea. Individuals had concentrations.