title: Spatio-temporal trends of PCBs in the Swedish freshwater environment 1981-2012.
abstract: Polychlorinated biphenyls (PCBs) have been monitored in perch (Perca fluviatilis), pike (Esox lucius), and Arctic char (Salvelinus alpinus) in reference lakes since the late 1960s. Temporal trends and spatial patterns are currently monitored in nine and 32 lakes, respectively. Overall, PCB concentrations are decreasing. However, this is not consistent for all congeners across all lakes and species. Perch has comparatively low PCB concentrations relative to suggested target levels, but individual congener concentrations in some lakes are concerningly high. No temporal trend is seen for CB-118 and CB-153 in perch, but significant decreasing trends exist for Arctic char and pike, for which monitoring started earlier than for perch. The lower/higher chlorinated congener ratio decreased over time in most lakes, indicating fewer new emissions. CB-118 and CB-153 concentrations in perch show spatial gradients across Sweden, with higher concentrations found near urban/industrial areas.
authors.affiliation: Department of Environmental Research and Monitoring, Swedish Museum of Natural History, Box 50007, 114 18, Stockholm, Sweden, Elisabeth.Nyberg@nrm.se.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Nyberg
authors.forename: Sara
authors.initials: S
authors.lastname: Danielsson
authors.forename: Ulla
authors.initials: U
authors.lastname: Eriksson
authors.forename: Suzanne
authors.initials: S
authors.lastname: Faxneld
authors.forename: Aroha
authors.initials: A
authors.lastname: Miller
authors.forename: Anders
authors.initials: A
authors.lastname: Bignert
mesh_terms: D000818:Animals; D004781:Environmental Exposure; D004784:Environmental Monitoring; D058735:Environmental Policy; D017859:Esocidae / Q000378:metabolism*; D005843:Geography; D060106:Lakes / Q000737:chemistry*; D010471:Perches / Q000378:metabolism*; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000378:metabolism*; D012621:Seasons; D013548:Sweden; D014337:Trout / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls