Can amino acid-specific stable carbon and nitrogen analysis improve quantifying arctic food web dynamics of persistent organic pollutants and mercury: A case study on the Greenland Sea food web

• Main Authors: Eulaers, Igor, Mosbech, Anders, Bossi, Rossana, Bouchard, Celine, Møller, Eva Friis, Sun, Jiachen, Søndergaard, Jens, Vorkamp, Katrin, Zubrod, Jochen P.
• Format: Conference Object
• Language: English
• Published: 2019
• Subjects: Arctic; Bouchard; Greenland; Greenland Institute of Natural Resources; Greenland Sea; Copepods
• Online Access: https://pure.au.dk/portal/da/publications/can-amino-acidspecific-stable-carbon-and-nitrogen-analysis-improve-quantifying-arctic-food-web-dynamics-of-persistent-organic-pollutants-and-mercury-a-case-study-on-the-greenland-sea-food-web(05745d24-7269-4e07-a698-2c4c9c0ced83).html; https://helsinki.setac.org/wp-content/uploads/2019/05/SETAC-Helsinki-Abstract-Book-2019.pdf

Can amino acid-specific stable carbon and nitrogen analysis improve quantifying arctic food web dynamics of persistent organic pollutants and mercury: a case study on the Greenland Sea food web I. Eulaers, Aarhus University AU Arctic Research Centre / Department of Bioscience; A. Mosbech, Aarhus University AU Arctic Research Centre / Department of Bioscience Arctic Environment; R. Bossi, Aarhus University Department of Environmental Science; C. Bouchard, Greenland Institute of Natural Resources / Greenland Climate Research Centre; E.F. Møller, Aarhus University AU Arctic Research Centre / Department of Bioscience Marine Diversity and Experimental Ecology; R. Schulz, University of Koblenz-Landau / Institute for Environmental Sciences; J. Sun, University of Antwerp / Department of Biology; J. Søndergaard, Aarhus University AU Arctic Research Centre; K. Vorkamp, Aarhus University Department of Environmental Science / Department of Environmental Science; J.P. Zubrod, University of Koblenz-Landau / Institute for Environmental Sciences Evaluating in situ biomagnification is a valuable posterior approach to further assess the chemical bioaccumulative potential of a substance identified a potential contaminant by its physicochemical characteristics, such as the octanol-water partitioning coefficient. The investigation of trophic magnification factors (TMFs) has consequently become the quantitative backbone of assessing real-world food web dynamics of contaminants. The reliability of TMFs rests however upon the accuracy with which the relative trophic level of the individuals investigated for their contaminant load is determined. In this respect, the advent of measuring stable carbon and nitrogen isotopes of individual amino acids, rather than of bulk tissue, seems particularly promising in eliminating uncertainty in food web baseline stable isotope values necessary to reliably determine relative trophic levels. The isotopic signature of essential amino acids remains in fact relatively unaltered throughout the food chain and therefore provides the food web baseline value for which previously only approximations could be employed. The Greenland Sea is a pristine Arctic marine ecosystem though its food web has up to now never been investigated for exposure to contaminants, such as mercury, persistent organic pollutants and per- and polyfluoroalkyl substances, typically found in the Arctic despite its remoteness from primary sources and ongoing mitigation under the Stockholm and Minamata Conventions. Being particularly interested in evaluating the performance of the amino acid-specific analysis based TMFs we investigate the food web dynamics of the above substances using both bulk tissue and compound-specific analysis for stable carbon and nitrogen isotopes. The food web investigated here composes particulate organic matter (POM), two copepod species, four amphipod species, three euphasiid species, twelve fish species, and four seabird species. The availability of POM and different primary consumers allows us to uniquely present on their bulk tissue and compound-specific stable isotope values, most often not available in food web assessments, and as such compare the performance of the TMFs resulting from both methods. Moreover, POM and copepods were collected at several locations allowing us to evaluate the spatial variation in food web baseline isotopic values, and how adequately amino acid-specific analysis can resolve this frequently stumbled upon issue when employing bulk tissue analysis.