title: Contaminant exposure and effects in Baltic ringed and grey seals as assessed by biomarkers.
abstract: The Baltic Sea ecosystem has suffered from a heavy pollutant load for more than three decades. Persistent organic pollutants (POPs) and heavy metals have been of most concern due to their persistence and toxic properties. Ringed seals (Phoca hispida baltica) and grey seals (Halichoerus grypus) living in the Baltic Sea have been suffering from pathological impairments, including reproductive disturbances, which have resulted in a depressed reproductive capacity. We investigated several biochemical parameters as potential biomarkers for exposure to and effects of the contaminant load in the Baltic seals. Seals from less polluted areas were used as reference material in terms of the pollution load. In both Baltic seal populations, the levels of some biochemical parameters diverged from those in the reference seals, and some of these showed a clear correlation with the individual contaminant load. Of the potential bioindicators, we propose cytochrome P4501A activity and vitamin E levels, in blubber or plasma, as exposure biomarkers for polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) in both species. The arylhydrocarbon receptor-mediated chemical-activated luciferase gene expression (CALUX) response reflects the whole PCB and DDT burden in ringed seals. Retinyl palmitate (vitamin A) levels showed a negative correlation with the individual POP load, and is proposed as potential effect biomarkers for the depletion of the vitamin A stores. As the nutritional levels of both vitamin A and E have an impact on the vitamin levels in the seals, more information on the dietary vitamin levels is needed before any conclusions can be drawn. As the relationship between biochemical parameters and contaminants varied between the two species, species-specific characteristics has to be considered when monitoring the health status and possible toxic effects of the contaminant load in ringed and grey seals.
authors.affiliation: Finnish Game and Fisheries Research Institute, Box 6, 00721 Helsinki, Finland. madeleine.nyman@rktl.fi
authors.forename: Madeleine
authors.initials: M
authors.lastname: Nyman
authors.forename: Magnus
authors.initials: M
authors.lastname: Bergknut
authors.forename: Marie Louise
authors.initials: ML
authors.lastname: Fant
authors.forename: Hannu
authors.initials: H
authors.lastname: Raunio
authors.forename: Marika
authors.initials: M
authors.lastname: Jestoi
authors.forename: Charlotta
authors.initials: C
authors.lastname: Bengs
authors.forename: Albertinka
authors.initials: A
authors.lastname: Murk
authors.forename: Jaana
authors.initials: J
authors.lastname: Koistinen
authors.forename: Christina
authors.initials: C
authors.lastname: Bäckman
authors.forename: Olavi
authors.initials: O
authors.lastname: Pelkonen
authors.forename: Mats
authors.initials: M
authors.lastname: Tysklind
authors.forename: Timo
authors.initials: T
authors.lastname: Hirvi
authors.forename: Eero
authors.initials: E
authors.lastname: Helle
mesh_terms: D000818:Animals; D001454:Baltic States; D015415:Biomarkers / Q000032:analysis; D003634:DDT / Q000009:adverse effects* / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000009:adverse effects* / Q000032:analysis*; D005260:Female; D005786:Gene Expression Regulation; D006304:Health Status; D007306:Insecticides / Q000009:adverse effects* / Q000032:analysis*; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D011078:Polychlorinated Biphenyls / Q000009:adverse effects* / Q000032:analysis*; D046048:Seals, Earless; D012680:Sensitivity and Specificity; D014801:Vitamin A / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000009:adverse effects* / Q000032:analysis*
chemical_list: D015415:Biomarkers; D004785:Environmental Pollutants; D007306:Insecticides; D014874:Water Pollutants, Chemical; D014801:Vitamin A; D003634:DDT; D011078:Polychlorinated Biphenyls; D008156:Luciferases