Abstract

Spatial and temporal trends of sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the Baltic Sea were evaluated by positive matrix factorization (PMF) and principal component analysis (PCA). Sediment cores were sampled at eight coastal, one coastal reference, and six offshore sites covering the northern to the southern Baltic Sea. The cores, which covered the period 1919-2010, were sliced into 2-3 cm disks among which 8-11 disks per core (in total 141 disks) were analyzed for all tetra- through octa-CDD/Fs. Identification and apportionment of PCDD/F sources was carried out using PMF. Five stable model PCDD/F congener patterns were identified, which could be associated with six historically important source types: (i) atmospheric background deposition (ABD), (ii) use and production of pentachlorophenol (PCP), (iii) use and production of tetra-chlorophenol (TeCP), (iv) high temperature processes (Thermal), (v) hexa-CDD-related sources (HxCDD), and (vi) chlorine-related sources (Chi), all of which were still represented in the surface layers. Overall, the last four decades of the period 1920-2010 have had a substantial influence on the Baltic Sea PCDD/F pollution, with 88 +/- 7% of the total amount accumulated during this time. The 1990s was the peak decade for all source types except TeCP, which peaked in the 1980s in the northern Baltic Sea and has still not peaked in the southern part. The combined impact of atmospheric-related emissions (ABD and Thermal) was dominant in the open sea system throughout the study period (1919-2010) and showed a decreasing south to north trend (always >80% in the south and >50% in the north). Accordingly, to further reduce levels of PCDD/Fs in the open Baltic Sea ecosystem, future actions should focus on reducing atmospheric emissions.

Published in

Environmental Science and Technology
2014, Volume: 48, number: 16, pages: 9531-9539
Publisher: AMER CHEMICAL SOC

SLU Authors

• Geladi, Paul

  • Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences
    

• Wiberg, Karin

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

Sustainable Development Goals

SDG6 Ensure availability and sustainable management of water and sanitation for all
SDG14 Conserve and sustainably use the oceans, seas and marine resources for sustainable development
SDG3 Ensure healthy lives and promote well-being for all at all ages


UKÄ Subject classification

Environmental Sciences
Other Physics Topics


Publication identifier

DOI: https://doi.org/10.1021/es502352p

Permanent link to this page (URI)

https://res.slu.se/id/publ/63458