title: Mercury and selenium biomagnification in a Brazilian coastal food web using nitrogen stable isotope analysis: a case study in an area under the influence of the Paraiba do Sul River plume.
abstract: Mercury (Hg), selenium (Se) and nitrogen (δ(15)N) stable isotope were assessed in a tropical food web of Rio de Janeiro's north coast. Isotopic data on muscle suggest a difference related to this parameter along the food web; where top-predators (cetacean and voracious fish) displayed heavier δ(15)N over the entire food web. Both top-predators presented similar δ(15)N values. Cetacean displayed higher Hg and lower Se than voracious fish. Five trophic positions (TP) were found in relation to primary consumer as baseline, ranging from 2.0 to 4.0. Positive relationships were found between trace-element and δ(15)N. The slope of regression equations (0.11 for Se and 0.21 for Hg) and food web magnification factors (2.4 for Se and 5.4 for Hg) showed that Hg presented higher rate of increase over the food web. Simultaneous measurements of trace-elements and ecological tracers emphasize the importance of TP into the trophic structure and distribution of Hg and Se throughout the food web.
authors.affiliation: Laboratório de Radioisótopos Eduardo Penna Franca, IBCCF, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, RJ, Brazil; Laboratório de Ciências Ambientais, CBB, Universidade Estadual do Norte Fluminense, 28013-602 Campos dos Goytacazes, RJ, Brazil. Electronic address: helena.kehrig@pq.cnpq.br.
authors.forename: Helena A
authors.initials: HA
authors.lastname: Kehrig
authors.affiliation: Laboratório de Radioisótopos Eduardo Penna Franca, IBCCF, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, RJ, Brazil; Departamento de Química, PUC-Rio, 22453-900 Rio de Janeiro, RJ, Brazil. Electronic address: terciaguedes@gmail.com.
authors.forename: Tercia G
authors.initials: TG
authors.lastname: Seixas
authors.affiliation: Laboratório de Radioisótopos Eduardo Penna Franca, IBCCF, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, RJ, Brazil. Electronic address: olaf@biof.ufrj.br.
authors.forename: Olaf
authors.initials: O
authors.lastname: Malm
authors.affiliation: Laboratório de Ciências Ambientais, CBB, Universidade Estadual do Norte Fluminense, 28013-602 Campos dos Goytacazes, RJ, Brazil. Electronic address: anapaula@uenf.br.
authors.forename: Ana Paula M
authors.initials: APM
authors.lastname: Di Beneditto
authors.affiliation: Laboratório de Ciências Ambientais, CBB, Universidade Estadual do Norte Fluminense, 28013-602 Campos dos Goytacazes, RJ, Brazil. Electronic address: crezende@uenf.br.
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Rezende
mesh_terms: D000818:Animals; D001938:Brazil; D004784:Environmental Monitoring / Q000379:methods*; D020387:Food Chain; D008628:Mercury / Q000032:analysis*; D009587:Nitrogen Isotopes / Q000032:analysis; D012643:Selenium / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D009587:Nitrogen Isotopes; D014874:Water Pollutants, Chemical; D008628:Mercury; D012643:Selenium
keywords: Biotransference; Coastal aquatic biota; Ecological tracer; Trace-element; Tropical ecosystem; Western South Atlantic Ocean