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Mercury biomagnification in a Southern Ocean food web
Seco, José; Aparício, Sara; Brierley, Andrew S.; Bustamante, Paco; Ceia, Filipe R.; Coelho, João P.; Philips, Richard A.; Saunders, Ryan A.Biomagnification of mercury (Hg) in the Scotia Sea food web of the Southern Ocean was examined using the stable isotope ratios of nitrogen (d15N) and carbon (d13C) as proxies for trophic level and feeding habitat, respectively. Total Hg and stable isotopes were measured in samples of particulate organic matter (POM), zooplankton, squid, myctophid fish, notothenioid fish and seabird tissues collected in two year...
High mercury levels in Antarctic toothfish Dissostichus mawsoni from the Southw...
Queirós, José P.; Hill, Simeon L.; Pinkerton, Matt; Vacchi, Marino; Coelho, João P.; Pereira, Eduarda; Ramos, Jaime A.; Seco, José; Stevens, Darren W.Mercury is a bioaccumulating toxic pollutant which can reach humans through the consumption of contaminated food (e.g. marine fish). Although the Southern Ocean is often portrayed as a pristine ecosystem, its fishery products are not immune to mercury contamination. We analysed mercury concentration (organic and inorganic forms - T-Hg) in the muscle of Antarctic toothfish, Dissostichus mawsoni, a long-lived top...
Main drivers of mercury levels in Southern Ocean lantern fish Myctophidae
Seco, José; Xavier, José C.; Bustamante, Paco; Coelho, João P.; Saunders, Ryan A.; Ferreira, Nicole; Fielding, Sophie; Pardal, Miguel A.Myctophids are the most abundant fish group in the Southern Ocean pelagic ecosystem and are an important link in the Antarctic marine food web. Due to their major ecological role, evaluating the level of mercury (Hg) contamination in myctophids is important as a step towards understanding the trophic pathway of this contaminant. The concentrations of total Hg were determined in muscle, gill, heart and liver tis...
Mercury levels in Southern Ocean squid: variability over the last decade
Seco, José; Xavier, José C.; Brierley, Andrew S.; Bustamante, Paco; Coelho, João P.; Gregory, Susan; Fielding, Sophie; Pardal, Miguel A.The concentrations of total and proportions of organic mercury were measured in tissues of 355 individuals of 8 species of Southern Ocean squid (Alluroteuthis antarcticus, Bathyteuthis abyssicola, Filippovia knipovitchi, Galiteuthis glacialis, Gonatus antarcticus, Kondakovia longimana, Psychroteuthis glacialis and Slosarczykovia circumantarctica). Squid were caught around South Georgia (Scotia Sea) during 5 cru...
Spatial Variation in Mercury Bioaccumulation and Magnification in a Temperate E...
Fonseca, Vanessa F.; França, Susana; Duarte, Bernardo; Caçador, Isabel; Cabral, Henrique N.; Mieiro, Cláudia L; Coelho, João P.; Pereira, EduardaEstuaries are renown sinks or repositories of contaminants and reflect historical pollution of persistent compounds. In particular, mercury (Hg) contamination is widespread in coastal environments and occurs in both inorganic (THg) and highly toxic organic forms (OHg) with high bioaccumulation potential. Trophic magnification factors have been increasingly used to quantify biomagnification and represent the ave...
Spatial variability in total and organic mercury levels in Antarctic krill Euph...
Seco, José; Xavier, José C.; Coelho, João P.; Pereira, Bárbara; Tarling, Geraint; Pardal, Miguel A.; Bustamante, Paco; Stowasser, GabrieleTotal and organic mercury concentrations were determined for males, females and juveniles of Euphausia superba collected at three discrete locations in the Scotia Sea (South Orkney Islands, South Georgia and Antarctic Polar Front) to assess spatial mercury variability in Antarctic krill. There was clear geographic differentiation in mercury concentrations, with specimens from the South Orkney Islands having tot...
Spatial Variation in Mercury Bioaccumulation and Magnification in a Temperate E...
Fonseca, Vanessa; França, Susana; Duarte, Bernardo; Caçador, Isabel; Cabral, Henrique; Mieiro, Cláudia L; Coelho, João P.; Pereira, EduardaEstuaries are renown sinks or repositories of contaminants and reflect historical pollution of persistent compounds. In particular, mercury (Hg) contamination is widespread in coastal environments and occurs in both inorganic (THg) and highly toxic organic forms (OHg) with high bioaccumulation potential. Trophic magnification factors have been increasingly used to quantify biomagnification and represent the ave...
Trophic web structure and ecosystem attributes of a temperate coastal lagoon
Bueno-Pardo, Juan; García-Seoane, Eva; Sousa, Ana I.; Coelho, João P.; Morgado, Mariana; Frankenbach, Silja; Ezequiel, João; Vaz, Nuno; Quintino, VictorA high quality data collection has been carried out between 2004 and 2014 to develop the first trophic ECOPATH model for the functioning of the sub and intertidal zones of Ria de Aveiro. This schematic representation allows the characterization of the most important compartments of biomass and flows of energy representing the functioning of the ecosystem, and can be used in the fields of decision-making and man...
Barn owl feathers as biomonitors of mercury: sources of variation
Roque, Inês; Lourenço, Rui; Marques, Ana; Coelho, João P.; Coelho, Cláudia; Pereira, Eduarda; Rabaça, João E.; Roulin, AlexandreGiven their central role in mercury (Hg) excretion and suitability as reservoirs, bird feathers are useful Hg biomonitors. Nevertheless, the interpretation of Hg concentrations is still questioned as a result of a poor knowledge of feather physiology and mechanisms affecting Hg deposition. Given the constraints of feather availability to ecotoxicological studies, we tested the effect of intraindividual differen...
Sustainable approach for recycling seafood wastes for the removal of priority h...
Monteiro, Rui J. R.; Lopes, Cláudia B.; Rocha, Luciana S.; Coelho, João P.; Duarte, Armando C.; Pereira, E.Mercury and cadmium are considered by the water framework directive priority hazardous substances. In this work, the capacity of crab carapace and clam shell wastes to remove mercury and cadmium from water was evaluated under batch conditions, for realistic contamination scenarios in monometallic and binary solutions. The results evidenced that in monometallic solutions and under studied operational conditions,...