Persistent Organic Pollutants in Streamwater: Influence of Hydrological Conditions and Landscape Type

Abstract

Concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), and hexachlorobenzene (HCB) in streamwater were measured in a remote catchment in northern Sweden and downstream to the Baltic Sea. Sampling took place at seven sites during two years and under different hydrological conditions: during the snow-free, snow-covered, and spring-flood seasons. Concentrations varied substantially between seasons and were up to 20 times higher during the spring flood compared to the preceding snow-covered period. The increase in concentrations with runoff was due to higher levels of particle-associated contaminants, while the dissolved concentrations remained stable. Particulate-contaminant concentrations were positively correlated primarily to suspended particulate matter (SPM) at sites in areas with a high land-cover fraction of sorted sediment. When upstream sampling locations were compared, a mire-dominated stream had higher concentrations and a lower retention of atmospherically deposited contaminants than a forest stream of the same catchment size. Contaminant concentrations (normalized to volume) did not increase consistently downstream despite the presence of several point sources. However, when normalized to the amount of SPM, concentrations were on average >20 times higher at the outlet in the Baltic Sea compared to the outlet from the remote catchment without point sources.

Published in

Environmental Science and Technology
2016, volume: 50, number: 14, pages: 7416-7424
Publisher: AMER CHEMICAL SOC

SLU Authors

• Josefsson, Sarah

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    
  • Geological Survey of Sweden (SGU)

• Futter, Martyn

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Jansson, Stina

  • Umeå University

• Laudon, Hjalmar

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

• Wiberg, Karin

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Future Forests

Global goals (SDG)

SDG6 Clean water and sanitation

UKÄ Subject classification

Forest Science

Publication identifier

• DOI: https://doi.org/10.1021/acs.est.6b00475

Permanent link to this page (URI)

https://res.slu.se/id/publ/77310