title: Particle-Dissolved Phase Partition of Polychlorinated Biphenyls in High Altitude Alpine Lakes.
abstract: We investigated whether polychlorinated biphenyls (PCBs) partitioning between the dissolved and particulate phases in two high altitude alpine lakes was determined by the quantity, size structure, or composition of suspended particles. Within- and between-lakes differences in water-particulate phase partition coefficient (Kp) were not related to total suspended matter, phytoplankton biomass, or taxonomic composition. Yet, a seasonal relationship between Kp and Kow was detected for both lakes, revealing equilibrium of PCBs partition when lakes were ice covered. On the contrary, PCBs partitioning between particles and water appeared kinetically limited during the open water season. Partition is therefore mainly governed by thermodynamic laws during the ice-covered period, while none of the tested physical or biological parameters seemed to explain the distribution of these particle-reactive contaminants in the open water period. PCBs were always mainly associated with particulate matter, but partitioning within different particulate size-fractions varied between seasons and between years during open water periods. When ice cover is absent, PCBs were mainly adsorbed on microplankton, the largest phytoplanktonic size fraction, which is the least likely to get grazed by pelagic microconsumers.
authors.affiliation: †University Savoie Mont-Blanc, LCME (Laboratory of Molecular Chemistry and Environment), 73000 Chambéry, France.|§University Savoie Mont-Blanc, UMR 42 CARRTEL, 73000 Chambéry, France.
authors.forename: Yann-Michel
authors.initials: YM
authors.lastname: Nellier
authors.affiliation: ‡INRA (French National Institute for Agronomical Research), UMR 42 CARRTEL (Alpine Research Centre for Lakes and Food webs), 74200 Thonon les Bains, France.|§University Savoie Mont-Blanc, UMR 42 CARRTEL, 73000 Chambéry, France.
authors.forename: Marie-Elodie
authors.initials: ME
authors.lastname: Perga
authors.affiliation: †University Savoie Mont-Blanc, LCME (Laboratory of Molecular Chemistry and Environment), 73000 Chambéry, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Cottin
authors.affiliation: †University Savoie Mont-Blanc, LCME (Laboratory of Molecular Chemistry and Environment), 73000 Chambéry, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Fanget
authors.affiliation: †University Savoie Mont-Blanc, LCME (Laboratory of Molecular Chemistry and Environment), 73000 Chambéry, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Naffrechoux
mesh_terms: D000531:Altitude; D018533:Biomass; D005602:France; D006863:Hydrogen-Ion Concentration; D046448:Ice Cover; D060106:Lakes / Q000032:analysis* / Q000737:chemistry; D010839:Phytoplankton; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D012621:Seasons; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls