title: Bioaccumulation and elimination of mercury in juvenile seabass (Dicentrarchus labrax) in a warmer environment.
abstract: Warming is an expected impact of climate change that will affect coastal areas in the future. These areas are also subjected to strong anthropogenic pressures leading to chemical contamination. Yet, the consequences of both factors for marine ecosystems, biota and consumers are still unknown. The present work aims to investigate, for the first time, the effect of temperature increase on bioaccumulation and elimination of mercury [(total mercury (THg) and methylmercury (MeHg)] in three tissues (muscle, liver, and brain) of a commercially important seafood species - European seabass (Dicentrarchus labrax). Fish were exposed to the ambient temperature currently used in seabass rearing (18°C) and to the expected ocean warming (+4°C, i.e. 22°C), as well as dietary MeHg during 28 days, followed by a depuration period of 28 days fed with a control diet. In both temperature exposures, higher MeHg contents were observed in the brain, followed by the muscle and liver. Liver registered the highest elimination percentages (EF; up to 64% in the liver, 20% in the brain, and 3% in the muscle). Overall, the results clearly indicate that a warming environment promotes MeHg bioaccumulation in all tissues (e.g. highest levels in brain: 8.1mgkg(-1) ww at 22°C against 6.2mgkg(-1) ww at 18°C after 28 days of MeHg exposure) and hampers MeHg elimination (e.g. liver EF decreases after 28 days of depuration: from 64.2% at 18°C to 50.3% at 22°C). These findings suggest that seafood safety may be compromised in a warming context, particularly for seafood species with contaminant concentrations close to the current regulatory levels. Hence, results point out the need to strengthen research in this area and to revise and/or adapt the current recommendations regarding human exposure to chemical contaminants through seafood consumption, in order to integrate the expected effects of climate change.
authors.affiliation: Division of Aquaculture and Seafood Upgrading, Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Avenida de Brasília, 1449-006 Lisboa, Portugal; Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Universidade do Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal; MARE - Marine and Environmental Sciences Centre, Laboratório Marítimo da Guia, Faculdade de Ciências da Universidade de Lisboa, Av. Nossa Senhora do Cabo, 939, 2750-374 Cascais, Portugal. Electronic address: aluisa@ipma.pt.
authors.forename: Ana Luísa
authors.initials: AL
authors.lastname: Maulvault
authors.affiliation: Division of Aquaculture and Seafood Upgrading, Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Avenida de Brasília, 1449-006 Lisboa, Portugal; Instituto Superior de Agronomia (ISA), School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Custódio
authors.affiliation: Division of Aquaculture and Seafood Upgrading, Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Avenida de Brasília, 1449-006 Lisboa, Portugal; Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Universidade do Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal; MARE - Marine and Environmental Sciences Centre, Laboratório Marítimo da Guia, Faculdade de Ciências da Universidade de Lisboa, Av. Nossa Senhora do Cabo, 939, 2750-374 Cascais, Portugal.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Anacleto
authors.affiliation: MARE - Marine and Environmental Sciences Centre, Laboratório Marítimo da Guia, Faculdade de Ciências da Universidade de Lisboa, Av. Nossa Senhora do Cabo, 939, 2750-374 Cascais, Portugal.
authors.forename: Tiago
authors.initials: T
authors.lastname: Repolho
authors.affiliation: Division of Aquaculture and Seafood Upgrading, Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Avenida de Brasília, 1449-006 Lisboa, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Pousão
authors.affiliation: Division of Aquaculture and Seafood Upgrading, Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Avenida de Brasília, 1449-006 Lisboa, Portugal; Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Universidade do Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal.
authors.forename: Maria Leonor
authors.initials: ML
authors.lastname: Nunes
authors.affiliation: UCIBIO, REQUIMTE Chemistry Department, Centre of Fine Chemistry and Biotechnology, Faculty of Sciences and Technology, Nova University of Lisbon (CQFB-FCT/UNL), 2829-516 Caparica, Portugal.
authors.forename: Mário
authors.initials: M
authors.lastname: Diniz
authors.affiliation: MARE - Marine and Environmental Sciences Centre, Laboratório Marítimo da Guia, Faculdade de Ciências da Universidade de Lisboa, Av. Nossa Senhora do Cabo, 939, 2750-374 Cascais, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Rosa
authors.affiliation: Division of Aquaculture and Seafood Upgrading, Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Avenida de Brasília, 1449-006 Lisboa, Portugal; Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Universidade do Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Marques
mesh_terms: D000818:Animals; D001492:Bass / Q000378:metabolism*; D001921:Brain / Q000378:metabolism; D057231:Climate Change; D004781:Environmental Exposure; D004784:Environmental Monitoring; D006358:Hot Temperature; D008099:Liver / Q000378:metabolism; D008628:Mercury / Q000737:chemistry / Q000378:metabolism*; D008767:Methylmercury Compounds / Q000737:chemistry / Q000378:metabolism*; D009132:Muscles / Q000378:metabolism; D011174:Portugal; D017747:Seafood / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism*
chemical_list: D008767:Methylmercury Compounds; D014874:Water Pollutants, Chemical; D008628:Mercury
keywords: Bioaccumulation; Elimination; European seabass; Methylmercury; Seawater warming