Impact of climate change on the mobilization and bioaccumulation of persistent organic pollutants in arctic freshwater systems

Legacy persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB) and other emerging pollutants such as perfluoralkyl substances (PFASs) and organophosphate ester (OPEs) flame retardants and plasticizers were measured in different soil, snow, water and char samples collected at selected areas from Cape Bounty lakes, rivers and surrounding ecosystems. An intense sampling campaign covering pre-melting, melting and open lake waters conditions (May-June-August 2016) was performed to assess POPs levels to study the main controls on the remobilization of organic pollutants from the terrestrial environment into two lakes and their main tributaries at Cape Bounty. Overall, the patterns of legacy and emerging pollutants in soil, snow and water were dominated by low molecular PCB congeners, short chain PFAS and the presence of HCB rather than heavier compounds, suggesting the importance of long-range atmospheric transport of POPs as the main vector for the introduction of these chemicals in Cape Bounty ecosystem. Statistically significant correlations between concentrations of PCBs on soil organic carbon content was found with a R squared of 0.36, while inorganic carbon was the main sorbing phase explaining the concentrations of perfluoroalkane sulfonate (PFSA), perfluordecane sulfonate (PFDS), perfluorohexane sulfonate (PFHxS) and perfluoroheptane sulfonate (PFHpS) in soils with a R squared range of 0.33-0.65. This suggests the important role of soils as reservoirs of legacy and emerging pollutants. Snow was also found to be an important reservoir of legacy PCBs as higher inputs of PCBs occurred into East & West rivers during melting processes, increasing PCBs concentration in riverine water up to 60 times. Although fish condition factors together with lipid content have declined significantly in West Lake, with lowest values associated with high turbidity (2013-16), no statistically significant differences were observed in West & East Lakes, on the concentrations of total PFASs (i. perfluoroacarboxylates (PFCAs) & ii. PFSAs - PFHxS & perfluorooctane sulfonate (PFOS)) in water and may reflect the high solubility of these compounds. The time series of PFCAs and PFOS (2008-15) in Arctic char from both Lakes showed declining trends, but a slight increase since 2013 was observed in West Lake, especially for PFOS, which may be associated with major permafrost disturbances that are occurring in West Lake compared to East Lake.

Identifier
Source https://www.polardata.ca/pdcsearch/PDCSearchDOI.jsp?doi_id=12828
Metadata Access http://www.polardata.ca/oai/provider?verb=GetRecord&metadataPrefix=fgdc&identifier=12828_fgdc
Provenance
Creator Cabrerizo, Ana; Muir, Derek; de Silva, Amila
Publisher Canadian Cryospheric Information Network
Contributor Polar Data Catalogue
Publication Year 2019
Rights Research programs, CCIN, or ArcticNet take no liability for the use or transmission of this data
OpenAccess true
Contact derek.muir(at)ec.gc.ca; pdc(at)uwaterloo.ca
Representation
Language English
Format Computer file
Discipline Environmental Research
Spatial Coverage (-110.000W, 74.000S, -109.000E, 76.000N)
Temporal Coverage Begin 2016-05-01T00:00:00Z
Temporal Coverage End 2018-09-28T00:00:00Z