A risk assessment of the effects of mercury on Baltic Sea, Greater North Sea and North Atlantic wildlife, fish and bivalves

• Published in: Environment International
• Main Authors: Rune Dietz, Jérôme Fort, Christian Sonne, Céline Albert, Jan Ove Bustnes, Thomas Kjær Christensen, Tomasz Maciej Ciesielski, Jóhannis Danielsen, Sam Dastnai, Marcel Eens, Kjell Einar Erikstad, Anders Galatius, Svend-Erik Garbus, Olivier Gilg, Sveinn Are Hanssen, Björn Helander, Morten Helberg, Veerle L.B. Jaspers, Bjørn Munro Jenssen, Jón Einar Jónsson, Kaarina Kauhala, Yann Kolbeinsson, Line Anker Kyhn, Aili Lage Labansen, Martin Mørk Larsen, Ulf Lindstøm, Tone K. Reiertsen, Frank F. Rigét, Anna Roos, Jakob Strand, Hallvard Strøm, Signe Sveegaard, Jens Søndergaard, Jiachen Sun, Jonas Teilmann, Ole Roland Therkildsen, Thorkell Lindberg Thórarinsson, Rune Skjold Tjørnløv, Simon Wilson, Igor Eulaers
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2021
• Subjects: Biological effect; Hg; Marine mammal; Seabird; Bird of prey; Risk threshold; Environmental sciences; GE1-350; North Atlantic
• Online Access: https://doi.org/10.1016/j.envint.2020.106178; https://doaj.org/article/bd0cadbb0bbd4a80a9097d99dc2d568a

A wide range of species, including marine mammals, seabirds, birds of prey, fish and bivalves, were investigated for potential population health risks resulting from contemporary (post 2000) mercury (Hg) exposure, using novel risk thresholds based on literature and de novo contamination data. The main geographic focus is on the Baltic Sea, while data from the same species in adjacent waters, such as the Greater North Sea and North Atlantic, were included for comparative purposes. For marine mammals, 23% of the groups, each composing individuals of a specific sex and maturity from the same species in a specific study region, showed Hg-concentrations within the High Risk Category (HRC) and Severe Risk Category (SRC). The corresponding percentages for seabirds, fish and bivalves were 2.7%, 25% and 8.0%, respectively, although fish and bivalves were not represented in the SRC. Juveniles from all species showed to be at no or low risk. In comparison to the same species in the adjacent waters, i.e. the Greater North Sea and the North Atlantic, the estimated risk for Baltic populations is not considerably higher. These findings suggest that over the past few decades the Baltic Sea has improved considerably with respect to presenting Hg exposure to its local species, while it does still carry a legacy of elevated Hg levels resulting from high neighbouring industrial and agricultural activity and slow water turnover regime.