title: PCB pollution continues to impact populations of orcas and other dolphins in European waters.
abstract: Organochlorine (OC) pesticides and the more persistent polychlorinated biphenyls (PCBs) have well-established dose-dependent toxicities to birds, fish and mammals in experimental studies, but the actual impact of OC pollutants on European marine top predators remains unknown. Here we show that several cetacean species have very high mean blubber PCB concentrations likely to cause population declines and suppress population recovery. In a large pan-European meta-analysis of stranded (n = 929) or biopsied (n = 152) cetaceans, three out of four species:- striped dolphins (SDs), bottlenose dolphins (BNDs) and killer whales (KWs) had mean PCB levels that markedly exceeded all known marine mammal PCB toxicity thresholds. Some locations (e.g. western Mediterranean Sea, south-west Iberian Peninsula) are global PCB "hotspots" for marine mammals. Blubber PCB concentrations initially declined following a mid-1980s EU ban, but have since stabilised in UK harbour porpoises and SDs in the western Mediterranean Sea. Some small or declining populations of BNDs and KWs in the NE Atlantic were associated with low recruitment, consistent with PCB-induced reproductive toxicity. Despite regulations and mitigation measures to reduce PCB pollution, their biomagnification in marine food webs continues to cause severe impacts among cetacean top predators in European seas.
authors.affiliation: Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Jepson
authors.affiliation: Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK.
authors.forename: Rob
authors.initials: R
authors.lastname: Deaville
authors.affiliation: Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, NR33 0HT, UK.
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Barber
authors.affiliation: Department of Animal Biology and Biodiversity Research Institute (IRBio), University of Barcelona, Barcelona, Spain.
authors.forename: Àlex
authors.initials: À
authors.lastname: Aguilar
authors.affiliation: Department of Animal Biology and Biodiversity Research Institute (IRBio), University of Barcelona, Barcelona, Spain.
authors.forename: Asunción
authors.initials: A
authors.lastname: Borrell
authors.affiliation: Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK.
authors.forename: Sinéad
authors.initials: S
authors.lastname: Murphy
authors.affiliation: Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, NR33 0HT, UK.
authors.forename: Jon
authors.initials: J
authors.lastname: Barry
authors.affiliation: Scottish Marine Animal Stranding Scheme, SRUC Veterinary Services Drummondhill, Stratherrick Road, Inverness, IV2 4JZ, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Brownlow
authors.affiliation: Environment and Sustainability Institute, University of Exeter, Cornwall Campus, Penryn, Cornwall TR10 9EZ, UK.
authors.forename: James
authors.initials: J
authors.lastname: Barnett
authors.affiliation: Marine and Freshwater Research Centre, Galway-Mayo Institute of Technology, Galway, Ireland.
authors.forename: Simon
authors.initials: S
authors.lastname: Berrow
authors.affiliation: Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK.
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Cunningham
authors.affiliation: Scottish Marine Animal Stranding Scheme, SRUC Veterinary Services Drummondhill, Stratherrick Road, Inverness, IV2 4JZ, UK.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Davison
authors.affiliation: Scottish Marine Animal Stranding Scheme, SRUC Veterinary Services Drummondhill, Stratherrick Road, Inverness, IV2 4JZ, UK.
authors.forename: Mariel
authors.initials: M
authors.lastname: Ten Doeschate
authors.affiliation: CIRCE, Conservation, Information and Research on Cetaceans, Cabeza de Manzaneda 3, Algeciras, 11390, Spain.
authors.forename: Ruth
authors.initials: R
authors.lastname: Esteban
authors.affiliation: Marine Animal Tissue Bank - Portugal, Soc. Portuguesa de Vida Selvagem, Dep. Biologia - Univ. do Minho &CESAM, Portugal.
authors.forename: Marisa
authors.initials: M
authors.lastname: Ferreira
authors.affiliation: Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36 Sweden.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Foote
authors.affiliation: Morigenos-Slovenian Marine Mammal Society, Kidričevo nabrežje 4, 6330 Piran, Slovenia.|Institute for Biodiversity Studies, Science and Research Centre, University of Primorska, Koper, Slovenia.|Department of Biodiversity, Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Koper, Slovenia.
authors.forename: Tilen
authors.initials: T
authors.lastname: Genov
authors.affiliation: Department of Conservation Biology, Estación Biológica de Doñana (EBD-CSIC), Americo Vespuccio S/N, Isla Cartuja, 42092, Sevilla, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: Giménez
authors.affiliation: Cornwall Wildlife Trust Marine Strandings Network, Five Acres, Allet, Truro, TR4 9DJ, UK.
authors.forename: Jan
authors.initials: J
authors.lastname: Loveridge
authors.affiliation: Coordinadora para o Estudio dos Mamíferos Mariños (CEMMA), Apartado 15, 36380 Gondomar, Pontevedra, Spain.
authors.forename: Ángela
authors.initials: Á
authors.lastname: Llavona
authors.affiliation: Sociedad de Estudios de Cetáceos en Canarias (SECAC), Lanzarote, Spain.
authors.forename: Vidal
authors.initials: V
authors.lastname: Martin
authors.affiliation: Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, NR33 0HT, UK.
authors.forename: David L
authors.initials: DL
authors.lastname: Maxwell
authors.affiliation: Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, NR33 0HT, UK.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Papachlimitzou
authors.affiliation: Marine Environmental Monitoring, Penwalk, Llechryd, Cardigan, Ceredigion, SA43 2PS, UK.
authors.forename: Rod
authors.initials: R
authors.lastname: Penrose
authors.affiliation: Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK.
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Perkins
authors.affiliation: The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
authors.forename: Brian
authors.initials: B
authors.lastname: Smith
authors.affiliation: Department of Conservation Biology, Estación Biológica de Doñana (EBD-CSIC), Americo Vespuccio S/N, Isla Cartuja, 42092, Sevilla, Spain.
authors.forename: Renaud
authors.initials: R
authors.lastname: de Stephanis
authors.affiliation: Cornwall Wildlife Trust Marine Strandings Network, Five Acres, Allet, Truro, TR4 9DJ, UK.
authors.forename: Nick
authors.initials: N
authors.lastname: Tregenza
authors.affiliation: CIRCE, Conservation, Information and Research on Cetaceans, Cabeza de Manzaneda 3, Algeciras, 11390, Spain.
authors.forename: Philippe
authors.initials: P
authors.lastname: Verborgh
authors.affiliation: Facultad de Veterinaria, Universidad de Las Palmas de Gran Canaria, Gran Canaria, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Fernandez
authors.affiliation: Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK.|Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, NR33 0HT, UK.
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Law
mesh_terms: D000818:Animals; D004289:Dolphins; D005060:Europe; D005260:Female; D005843:Geography; D008297:Male; D011078:Polychlorinated Biphenyls / Q000009:adverse effects*; D011157:Population Dynamics; D062211:Spatio-Temporal Analysis; D014873:Water Pollutants / Q000009:adverse effects*; D014877:Water Pollution, Chemical; D050685:Whale, Killer
chemical_list: D014873:Water Pollutants; D011078:Polychlorinated Biphenyls