title: Trophodynamics of mercury and other trace elements in a pelagic food chain from the Baltic Sea.
abstract: Mercury (Hg) and 13 other trace elements (Al, Ti, V, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb) were measured in phytoplankton, zooplankton, mysis and herring in order to examine the trophodynamics in a well-studied pelagic food chain in the Baltic Sea. The fractionation of nitrogen isotopes (delta(15)N) was used to evaluate food web structure and to estimate the extent of trophic biomagnification of the various trace elements. Trophic magnification factors (TMFs) for each trace element were determined from the slope of the regression between trace element concentrations and delta(15)N. Calculated TMFs showed fundamental differences in the trophodynamics of the trace elements in the pelagic food chain studied. Concentrations of Al, Fe, Ni, Zn, Pb and Cd showed statistically significant decreases (TMF<1) with increasing trophic levels and thus these trace elements tropically dilute or biodilute in this Baltic food chain. Cu, As, Cr, Mn, V, Ti and Co showed no significant relationships with trophic levels. Hg was unique among the trace elements studied in demonstrating a statistically significant increase (TMF>1) in concentration with trophic level i.e. Hg biomagnifies in this Baltic food chain. The estimated TMF for Hg in this food chain was comparable to TMFs observed elsewhere for diverse food chains and locations.
authors.affiliation: Department of Applied Environmental Science (ITM), Geohuset Svante Arrhenius väg 8C, Stockholm University, SE 106 91 Stockholm, Sweden.
authors.forename: Erick
authors.initials: E
authors.lastname: Nfon
authors.forename: Ian T
authors.initials: IT
authors.lastname: Cousins
authors.forename: Olli
authors.initials: O
authors.lastname: Järvinen
authors.forename: Arun B
authors.initials: AB
authors.lastname: Mukherjee
authors.forename: Matti
authors.initials: M
authors.lastname: Verta
authors.forename: Dag
authors.initials: D
authors.lastname: Broman
mesh_terms: D004784:Environmental Monitoring; D020387:Food Chain; D008628:Mercury / Q000032:analysis*; D009792:Oceans and Seas; D012623:Seawater / Q000737:chemistry*; D014131:Trace Elements / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014131:Trace Elements; D014874:Water Pollutants, Chemical; D008628:Mercury