| 1. |
- Dahlberg, Anna-Karin, et al.
(författare)
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Dispersal of persistent organic pollutants from fiber-contaminated sediments : biotic and abiotic pathways
- 2021
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Ingår i: Journal of Soils and Sediments. - : Springer Science and Business Media LLC. - 1439-0108 .- 1614-7480. ; 21:4, s. 1852-1865
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Tidskriftsartikel (refereegranskat)abstract
- PurposeNumerous sites contaminated with fiber emissions from pulp and paper industries are found in coastal areas of the Baltic Sea, but there is limited knowledge about the magnitude of dispersal of persistent organic pollutants (POPs) from these anthropogenic, organic-rich sediments called fiberbanks. The aim of this study was to quantify and compare different POP dispersal pathways from such fiberbanks. Dispersal mechanisms studied included abiotic and biotic routes (dissolved in water, particle-bound, and bioaccumulation).Materials and methodsContaminated fibrous sediments located in Ångermanälven River estuary in north-eastern Sweden were studied in sediment types representing different fiber content (i.e., fiberbanks, fiber-rich sediments, and less fiber impacted sediments). Sediment-to-water fluxes of dissolved contaminants (polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and dichlorodiphenyltrichloroethane (DDT)) were measured in situ using benthic flux chambers. Particle resuspension was measured by sampling bottom water, before and after disturbing the sediment surface. Benthic biota was collected to determine the body burden of contaminants and to determine biota-pore water accumulation factors (BAFPW) and biota-sediment accumulation factors (BSAFs). In addition, concentrations of dissolved POPs in the water column were measured in field using passive samplers. Instrumental analysis was performed using gas chromatography coupled to a triple quadrupole mass spectrometer (GC-MS/MS).Results and discussionThe flux of dissolved Σ20PCBs was approximately two times higher from one of the investigated fiberbanks (3.4 ng m− 2 day− 1) compared to the other. The average particle burden of PCBs was also higher at this fiberbank after artificial disturbance (15 ng g−1 particle), which indicates that larger amounts of contaminants are likely to disperse via particle resuspension from this site compared to the other fiberbank (4.8 ng g− 1 particle). The difference might be associated with a layer of recently settled minerogenic material that covers one of the fiberbanks, which probably functions as a protective barrier. The lack of benthic biota implies that contaminant release by bioturbation is negligible in the studied fiberbanks. However, benthic biota from fiber-rich sediment showed bioaccumulation and biomagnification of contaminants.ConclusionsThe importance of diffusive flux from fiberbanks under undisturbed conditions became apparent when the different dispersal pathways were quantified. However, no dispersal pathway could be judged as irrelevant, since even under undisturbed conditions, advective particle transport was significant. Additionally, the uptake by biota and trophic transfer can be considerable. Quantification of dispersal routes and understanding of the relative importance of various pathways is critical for proper risk assessment and management of contaminated sediments.
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| 2. |
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| 3. |
- Dahlberg, Anna-Karin, 1982-, et al.
(författare)
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Persistent organic pollutants in wood fiber–contaminated sediments from the Baltic Sea
- 2020
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Ingår i: Journal of Soils and Sediments. - : Springer Science and Business Media LLC. - 1439-0108 .- 1614-7480. ; 20:5, s. 2471-2483
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Tidskriftsartikel (refereegranskat)abstract
- Many coastal areas in the Baltic Sea are contaminated with wood fiber and pollutants from pulp and paper industries. These anthropogenic, organic-rich, sediments (fiberbanks) have not been characterized and knowledge about their role as secondary sources for dispersal of persistent organic pollutants (POPs) is limited. Hence, the aim of this study was to elucidate the fate of POPs and the relationships between sorption (KD and KTOC), sediment type, and compound hydrophobicity (KOW) in fiber-contaminated sediments.
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| 4. |
- Goransson, Gunnel, et al.
(författare)
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Assessing the Risk of Contaminant Dispersion From Fibrous Sediments of Industrial Origin
- 2021
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Ingår i: Frontiers in Marine Science. - : Frontiers Media S.A.. - 2296-7745. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Unregulated discharges of wastewater from pulp and paper factories resulted in the formation of relatively thick organic (cellulose) rich sediments in shallow waters along the Swedish coast. These deposits are known as fiberbanks and are contaminated by persistent organic pollutants (POPs), metals and methylmercury, which can be dispersed by diffusion and advective processes coupled to propeller wash, high river discharges, strong wind waves and submarine landslides. Based on a case study of polychlorinated biphenyls (PCBs), one group of prevalent POPs in the fiberbanks, we present a probabilistic approach to estimate the potential risk of dispersion of fiberbank contaminants. The approach allows for estimation of the dispersal pathways that dominates the risk within a given time and provides more insight about the significance of various dispersion processes. We show that it is highly likely that chemical diffusion and advection triggered by ship-induced resuspension will disperse PCBs (sum of seven congeners; sigma 7PCB) above a threshold level for environmental impact, while the likelihood of river and wind-wave generated resuspension dispersion pathways are lower (similar to 20%, respectively). We further show that there is approximately 5% likelihood that a submarine landslide will disperse sigma 7PCB above the threshold level. The study implies that the governing parameters for risk assessment specifically should include reliable data on contaminant concentration, water depth above the fiberbank, estimation of concerned fiberbank areas, time duration of erosive fluid flows and measured diffusion. The approach provides insight into the importance of various dispersion processes. We suggest that it can be applied to support risk assessment, especially when there are limited available data and/or knowledge about the system under study.
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| 5. |
- Almroth Rosell, Elin, 1977, et al.
(författare)
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Effects of simulated natural and massive resuspension on benthic oxygen, nutrient and dissolved inorganic carbon fluxes in Loch Creran, Scotland
- 2012
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Ingår i: Journal of Sea Research. - : Elsevier BV. - 1385-1101. ; 72, s. 38-48
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Tidskriftsartikel (refereegranskat)abstract
- The effect of repeated natural resuspension on benthic oxygen consumption and the effect of natural and massive resuspension on oxygen consumption and fluxes of phosphate, silicate, ammonium and dissolved inorganic carbon (DIC) were studied at two stations (S1 and S2) in a Scottish sea loch. Station S11 had organically enriched sediment and station S1 had lower organic content in the sediment. The fluxes were measured in situ using the Göteborg benthic lander. Natural resuspension, simulating resuspension events due to strong wind, waves or currents, and massive resuspension, simulating resuspension due to e.g. trawling or dredging, were created inside the incubation chambers by regulating the stirring of the incubated overlying water or by retracting and shaking the incubated sediment. Natural resuspension showed clear effects on the oxygen consumption at station S11, where it increased with an average of 12.8 (standard error (s.e.) 0.17) and 7.7 (s.e. 0.12) mmol m− 2 d− 1 during the first and second incubations, respectively. At station S1 there was no clear effect of natural resuspension on the oxygen consumption. Massive resuspension increased the oxygen consumption on S1 with an average of 608 (standard deviation (sd) 366) mmol m− 2 d− 1 and on S11 with an average of 2396 (sd 2265) mmol m− 2 d− 1. The fluxes of ammonium, phosphate and silicate were affected by the massive resuspension in 50, 14 and 33% of the chambers, respectively, on station S11. However, in the majority of the cases there were no effects on the nutrient and DIC fluxes of massive resuspension. The absolute concentrations of DIC, ammonium and silicate did however instantly increase with an average of 419 (sd 297), 48 (sd 27) and 6.9 (sd 3.7) μM, respectively, at S11 upon massive resuspension. The concentrations of phosphate decreased instantly with an average of 0.2 (sd 0.1) μM. On station S1 there were effects only on the ammonium and silicate concentrations, which increased with 0.8 (sd 0.3) and 1.13 (sd 0.36) μM, respectively. The large increase in oxygen consumption due to massive resuspension indicates that activities like e.g. trawling and dredging that take place in areas where water exchange occurs infrequently may lead to oxygen depletion in bottom water, which in turn might affect the ecological balance. Silicate, ammonium and DIC can be released due to massive resuspension and contribute to increased algal blooms in surface waters.
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| 6. |
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| 7. |
- Apler, Anna, 1980-
(författare)
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Contaminated organic sediments of anthropogenic origin: impact on coastal environments
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Baltic Sea is negatively affected by legacy pollutants such as metals and persistent organic pollutants (POPs) that are known to have adverse effects on living organisms, including, humans and were banned decades ago. This thesis addresses the dispersal of these pollutants from heavily contaminated, cellulose-rich sediments of industrial origin in the Ångermanälven river estuary in northern Sweden. Relatively thick deposits, known as fiberbanks, in the studied area derive from historical wastewater emissions from the pulp and paper industry (P&PI) that began in the 19th century. These fiberbanks formed on shallow seabeds, where they currently remain. In addition, extensive areas of the deeper seabed are covered by fiber-rich sediments. The fiberbanks contain higher levels of pollutants than the fiber-rich sediments and the sediments less affected by P&PI emissions, and the fiberbank concentrations may be of ecotoxicological concern. Metals and POPs were found to be strongly partitioned to organic material and partitioning coefficients were higher in fiberbanks that contain elevated levels of organic matter. Metals and POPs were detectable in sampled pore water, even if low sediment-water fluxes of metals were expected. Metal contaminant concentrations in sampled bottom water were measured before and after resuspension of underlying sediments, which showed that concentrations of particle bound metals dominated over dissolved forms. One out of three studied fiberbank sites was covered with a natural capping layer that probably shields the water column from metals in the deposit underneath. Studies of geological archives in the form of sediment cores show the rise and fall of an anthropogenic industrial era and the recovery of an aquatic system, but the established chemostratigraphy fails to reveal the current hotspots (fiberbanks) that will stay for decades to come. The potential impacts of climate change and isostatic land uplift are factors that complicate the long-term risk assessment of fiberbanks. These knowledge gaps combined with the lack of a common risk assessment strategy for contaminated sediments hinder the achievement of national quality objectives (NQOs) and fulfillment of Agenda 2030 goals. Fiberbanks resulted from an accelerating global demand for paper products and hence, the issue of these artificial seabed forms is an example of how the geological epoch of humankind, the Anthropocene, can be viewed in a cross-scalar perspective and be important in the management of a sustainable future in the Baltic Sea region.
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| 8. |
- Apler, Anna, 1980-
(författare)
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Dispersal and environmental impact of contaminants in organic rich, fibrous sediments of industrial origin in the Baltic Sea
- 2018
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The health of the Baltic Sea is negatively affected by hazardous substances such as metals and persistent organic pollutants (POPs), which include legacy pollutants that were banned decades ago, but still circulate in the ecosystem. Elevated levels of legacy pollutants, identified by HELCOM as key hazardous substances, have been found in accumulations of fibrous sediments, so-called fiberbanks and fiber-rich sediments, which derive from old pulp mills along the Swedish north coast. The fiberbanks are deposited in shallow water and bathymetrical models show evidence of their erosion, potentially caused by propeller wash, submarine landslides and gas ebullition. This thesis addresses the potential dispersal of key substances from three fiberbank sites located in a non-tidal Swedish estuary, in which metals and POPs are present in concentrations that may pose a risk for benthic organisms. Metals and POPs are partitioned to organic material and, as expected, show the highest partitioning coefficients (KD) in fiberbanks that have higher TOC levels compared to adjacent areas with fiber-rich sediments (natural clay sediments mixed up with fibers) or relatively unaffected postglacial clays. However, many analytes were found to be present in quantifiable concentrations in pore water, which indicates diffusion of substances from the solid phase to the aqueous phase. To assess the dispersive influence of an abrupt erosional event on dispersion, metals were measured in undisturbed bottom water and in bottom water disturbed by artificial re-suspension of fibrous sediments. The bioavailable, dissolved fraction of metals decreased in bottom water after re-suspension, probably due to the particle concentration effect. In contrast, the total concentrations of metals and number of quantifiable metals increased with particle concentration caused by re-suspension. At one station, the total concentration of chromium (Cr) was elevated to a level where it may lower the ecological status of the water body during periods of substantial erosion (e.g. spring floods or submarine landslides). Analyses of disturbed bottom water revealed, however, that minerogenic particles were preferentially re-suspended compared to organic. This suggests that physical erosion and re-suspension of fiberbank sediments might have a larger effect on dispersal of metals than on POPs.
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| 9. |
- Apler, Anna, 1980-, et al.
(författare)
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Dispersal of cellulose fibers and metals from contaminated sediments of industrial origin in an estuary
- 2020
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424. ; 266:3
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Tidskriftsartikel (refereegranskat)abstract
- The boreal forest’s pulp and paper industry plays a major role in economic prosperity but, historically, caused an environmental burden. Remnants of discharges of contaminated suspended solids (fiberbanks) are continuously being discovered on the beds of shallow seas, rivers and lakes in the northern hemisphere. We investigated the dispersion of Cd, Cr, Cu, Hg, Ni, Pb and Zn from deeper to surficial layers in fiberbanks in a Swedish estuary and the larger-scale transport of the same metals to distal areas of sediment accumulation. We also tested the C:N ratio as a common denominator for these anthropogenic, cellulose-rich deposits. Sampling and analyses of three fiberbanks located in the inner part of the estuary and from sediment accumulation sites outside and along the estuary reveals that metal concentrations are regressing to background levels towards the surface at the accumulation sites. The fiberbanks show a higher degree of contamination and C:N ratios demonstrate inclusion of cellulose fibers. C:N ratios also indicate that there is currently no significant transport of fiberbank material into the distal areas. A ∼10 cm natural cap of recently settled fine-grained sediment covering one of the fiberbanks seems to prevent metals dispersing into overlying water whereas the other two fiberbanks show signs of metal enrichment and potential mercury methylation in surficial layers. Although the estuarine system seems to recover from the impact of industrial waste, there is no evidence that the fiberbanks will be remediated naturally but instead will continue to threaten the aquatic environment.
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| 10. |
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| 11. |
- Apler, Anna, 1980-, et al.
(författare)
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Distribution and dispersal of metals in contaminated fibrous sediments of industrial origin
- 2019
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 215, s. 470-481
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Tidskriftsartikel (refereegranskat)abstract
- Industrial emissions can impact aquatic environments and unregulated discharges from pulp and paper factories have resulted in deposits of cellulose fiber along the Swedish coast. These deposits are contaminated by metals, but due to their unique fibrous character the extent of sorption and dispersal of the metals is unclear. Fibrous sediments were sampled at two sites in the Ångermanälven river estuary, Sweden. The partitioning of metals between the sediment, pore water and bottom water was investigated and the degree of bioavailability was evaluated. The levels of metals in the sediment were high in fibrous or offshore samples, depending on the metal, whereas the levels of dissolved metals in pore water were low or below the limit of quantification. Partition coefficients (KD) showed that sorption to the sediment was stronger at one of the fibrous sites, possibly related to the type and size of organic matter. Undisturbed bottom water samples contained low levels of both dissolved and particle bound metals, but when comparing measured metal concentrations to threshold values of ecological status and ecotoxicological assessment criteria, both sediments and bottom water may be detrimental to living organisms. In-situ re-suspension experiments showed that the concentrations of particle bound metals increased whereas the dissolved concentrations decreased. The analyzed metals are probably retained by the solid phases of the fibrous sediment or adsorbed to particles in the water, reducing their bioavailability.
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| 12. |
- Apler, Anna, et al.
(författare)
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Swedish status and trend monitoring programme Chemical contamination in offshore sediments 2003– 2014
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In 2003, a national Swedish status and monitoring programme for contaminants in marine sediment (SSTMP) was launched. The programme is funded by the Swedish Environmental Protection Agency (Swedish EPA) with the objective to investigate the status and long-termtrends of contaminants in the open sea within Swedish territorial water and Exclusive Economic Zone (EEZ). The programme includes sampling and analyses of surface sediments in 16 offshore stations every 5–6 years in order to fit the water management cycle in EU marine legislation. The monitoring stations are placed in the largest depressions along the Swedish coast and the obtained data can be used for a number of purposes such as following up on three of Sweden’s 16 environmental objectives: A non-toxic environment, A balanced marine environment, flourishing coastal areas and archipelagos and Zero eutrophication. From the start the SSTMP has been carried out in cooperation with the Swedish Radiation Safety Authority (SSM) to meet the requirements of radioactivity monitoring in sediments. Data of radionuclides in sediment are used to follow-up on the national environmental objective A safe radiation environment. The framework of the SSTMP has been designed in accordance with recommendations from both the governing bodies for the protection of the marine environments in the Baltic Sea (HELCOM) and the North-East Atlantic (OSPAR).16 offshore sample stations have been chosen to monitor pollutant levels in Swedish offshore sediments. Each sample station is defined as a circle with a 50 m radius in which seven sites for surface sediment sampling are randomly chosen at every monitoring occasion. The collected sediment is then analysed for heavy metals, organic substances and nutrients. By doing this, the accumulation of contaminants during recent years can be monitored. In addition to chemical data, geological information, underwater photographs and CTD data have been obtained at every station with the right conditions. All chemical data with additional information are available through the public database for sediment monitoring data at SGU’s web site: www.sgu.se. Data is also reported to ICES (www.ices.dk).The compiled results from 2003, 2008 and 2014 reveal that there is no general declining trend of the levels of elements and organic micropollutants in surface sediments around the Swedish coast. The different monitored offshore areas are still supplied with heavy metals and organic substances in volumes significant enough to increase the concentrations of some analytes. The levels of metals varies between the different basins. For example, arsenic shows high concentrations in the Bothnian Bay and Bothnian Sea, while cadmium shows the most elevated levels in the Baltic Proper. The concentrations of most of the presented organic substances have declined since 2008. The levels of hexachlorobenzene (HCB) on the other hand increase at almost all of the offshore stations, whilst the PAHs decrease in most sea basins. However, it is important to stress that no statistical analyses have been carried out to establish the statistical significance of the variations between years. Instead, only the concentration of each pollutant has been used to compare between years. For a selection of elements and organic pollutants there are available statistical assessment criteria developed and published by the Swedish EPA. If concentrations of the presented elements and organic substances are classified according to these criteria, it is shown that many of them occur in high to very high levels in the surface sediments. This is surprising since measures have been taken to decrease use and releases to the environment, for example most of the monitored pesticides were banned in Sweden in the 1970s. According to the ecotoxicological assessment criteria set by the Swedish Agency for Marine and Water Management (SwAM) TBT levels exceed the levels that are thought to cause negative effects to benthic organisms.
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| 13. |
- Apler, Anna, 1980-, et al.
(författare)
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The Anthropocene in the northern Baltic Sea – the case of contaminated fiberbanks and implications for sustainable development
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The epoch of humankind, the Anthropocene, is usually characterized by the global gaze, which places its focus on global environmental phenomena i.e. global warming and ocean acidification. In this article we argue that the Anthropocene could be better understood with a cross-scalar perspective and present the case of anthropogenic contaminated “fiberbanks” as an example. We present a geological example of the Anthropocene in a Swedish river estuary in the northern Baltic Sea, which hosted nine P&P mills along its’ shores and received large amounts of metal containing wastewater during the 20th century. As a result of the great acceleration and an increased national and global demand for pulp and paper products these fiberbanks formed in shallow waters. As artificial seabed features these thick deposits of contaminated organic-rich material negatively affect the adjacent aquatic environment. By constructing a chemostratigraphy based on sediment cores from accumulation areas and a metal pollution index we show how the aquatic system has recovered from metal pollution. We note, however, that the established stratigraphy fails to identify the fiberbanks, which remain in the shallow zones and are contaminant hotspots. In Sweden, there is an insufficient knowledge of contaminated sediments for a sustainable water and marine management. This knowledge gap in combination with human induced climate changes that may chemically and physically affect sediments and thus, alter dispersion of imbedded pollutants, results in poor understanding and long-term perception of the risks of contaminant dispersion from fiberbanks. We claim that these gaps of knowledge must be filled in order to reach an effective conservation at the same time as a sustainable blue growth in the northern Baltic Sea.
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| 14. |
- Cathalot, C., et al.
(författare)
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Spatial and Temporal Variability of Benthic Respiration in a Scottish Sea Loch Impacted by Fish Farming: A Combination of In Situ Techniques
- 2012
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Ingår i: Aquatic geochemistry. - : Springer Science and Business Media LLC. - 1380-6165 .- 1573-1421. ; 18:6, s. 515-541
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Tidskriftsartikel (refereegranskat)abstract
- The effects of fish farm activities on sediment biogeochemistry were investigated in Loch Creran (Western Scotland) from March to October 2006. Sediment oxygen uptake rates (SOU) were estimated along an organic matter gradient generated from an Atlantic salmon farm using a combination of in situ techniques: microelectrodes, planar optode and benthic chamber incubations. Sulphide (H2S) and pH distributions in sediment porewater were also measured using in situ microelectrodes, and dissolved inorganic carbon (DIC) fluxes were measured in situ using benthic chambers. Relationships between benthic fluxes, vertical distribution of oxidants and reduced compounds in the sediment were examined as well as bacterial abundance and biomass. Seasonal variations in SOU were relatively low and mainly driven by seasonal temperature variations. The effect of the fish farm on sediment oxygen uptake rate was clearly identified by higher total and diffusive oxygen uptake rates (TOU and DOU, respectively) on impacted stations (TOU: 70 ± 25 mmol O2 m-2 day-1; DOU: 70 ± 32 mmol O2 m-2 day-1 recalculated at the summer temperature), compared with the reference station (TOU: 28.3 ± 5.5 mmol O2 m-2 day-1; DOU: 21.5 ± 4.5 mmol O2 m-2 day-1). At the impacted stations, planar optode images displayed high centimetre scale heterogeneity in oxygen distribution underlining the control of oxygen dynamics by small-scale processes. The organic carbon enrichment led to enhanced sulphate reduction as demonstrated by large vertical H2S concentration gradients in the porewater (from 0 to 1,000 lM in the top 3 cm) at the most impacted site. The impact on ecosystem functions such as bioirrigation was evidenced by a decreasing TOU/DOU ratio, from 1.7 in the non-impacted sediments to 1 in the impacted zone. This trend was related to a shift in the macrofaunal assemblage and an increase in sediment bacterial population. The turnover time of the organic load of the sediment was estimated to be over 6 years.
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| 15. |
- Cato, Ingemar, et al.
(författare)
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Metaller och miljögifter i sediment – inom Stockholms stad och Stockholms län 2007
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Sveriges geologiska undersökning (SGU) har på uppdrag, dels av Enheten för Miljöanalys vid Länsstyrelsen i Stockholms län, dels av Miljöförvaltningen vid Stockholms stad i oktober 2007 genomfört provtagningar av ytsediment för miljökemiska analyser inom såväl Stockholms stad som inom Stockholms läns kustvatten samt Mälarens östligaste del. 2010 gav länsstyrelsen SGU i uppdrag att låta analysera de nedfrysta och arkiverade sedimentproven som togs 2007. Dessa analyserades med avseende på grundämnen (bl.a. metaller) och vissa organiska miljögifter. Resultaten skulle redovisas i en samlad gemensam rapport med motsvarande analysdata från Stockholms stads prover. De senare proverna analyserades redan 2007/2008.Provtagningarna genomfördes på av SGU tidigare (1997-2001) framtagna och provtagna stationer placerade på lämpliga ackumulationsbottnar. SGUs tidigare provtagningar genomfördes inom ramen för SGUs marina miljökemiska sedimentprogram som är kopplat till SGUs statsuppdrag att kartlägga Sveriges kontinentalsockelområde (territorialhav och ekonomiska zon, EEZ). Två nya stationer etablerades 2007 för Stockholms stads räkning vid Hägersten i Mälaren och vid Lidingöbro i saltsjön.Provtagningsplatserna har dokumenterats med undervattensfoto och samtliga upphämtade sedimentkärnor har beskrivits samt dokumenterats med foto och röntgenteknik. De senare för radiografisk analys för klarläggande av inre sedimentstrukturer och eventuell förekomst av fysiska störningar, t.ex. genom ankring eller biologisk omröring (bioturbation).Det översta sedimentskiktet (0-1 cm) har på samtliga 29 sedimentkärnor uttagits för analys av halten organiskt material och näringsämnen (kol, kväve och fosfor), 57 grundämnen, bl.a. tungmetallerna arsenik (As), kadmium (Cd), kobolt (Co), krom (Cr), koppar (Cu), kvicksilver (Hg), nickel, (Ni), bly (Pb) och zink (Zn) samt polycykliska aromatiska kolväten (PAH). På 8 stationer inom centrala Stockholm analyserades även hexaklorbensen (HCB) och polyklorerade bifenyler (PCB).Samtliga stationer har klassats med avseende på miljökvalitet för var och en av de metaller och organiska miljögifter som omfattas av de svenska bedömningsgrunderna för sediment i kust och hav. Med undantag för arsenik, kobolt och krom återfinns de högsta koncentrationerna i centrala Stockholm och ut till Oxdjupet samt in i Mälaren till Vårberg (vid Skärholmen). På samtliga dessa stationer faller miljöstatusen för Cd, Cu, Hg, Pb och Zn samt PAH, och HCB i klass 5 (mycket höga halter) med en avklingning mot Oxdjupet respektive Vårberg till klass 4 (hög halt). Samtliga stationer för PCB faller i klass 5. Klasserna 1-2 representerar stationer utspridda i den yttre skärgården utanför dessa gradienter. Endast kobolt (Co) uppträder enbart i de klasser som utgör den naturliga bakgrunden (klass 1) eller något högre (klass 2). Merparten av stationerna med avseende på As, Pb, Cr och Ni och i viss mån bly (Pb) ligger också i dessa två lägsta klasser 1-2.Den stationsvisa koncentrationsförändringen över tiden (dvs. mellan perioderna 1997-2001 och 2007) av respektive undersökt ämne/substans redovisas och illustreras med diagram. Med hjälp av medel- och medianvärdesförändringen för samma period ges en ? generell bild av utvecklingen för den miljökemiska statusen i bottnarna inom Stockholms läns kustavsnitt och östligaste delen av Mälaren.Medel- och medianvärdesförändringar av halterna för respektive undersökta ämnen har genomförts antingen för hela undersökningsområdet med eller utan data från centrala Stockholm (den s.k. Stockholms-Mälar-gradienten mellan Vårberg/Strömmenoch Oxdjupet) och för delområden som t.ex. centrala Stockholm, norra respektive södra skärgårdshavet. Detta då trenderna i många fall är helt olika i dessa områden för ett och samma ämne. Sannolikheten för de ovan beskrivna medelvärdesförändringarna har dessutom testas statistiskt med hjälp av s.k. t-test med (n-1) frihetsgrader för matchade datapar (dvs. data från samma stationer men härrörande från de två provtagningsperioderna 1997-2001 och 2007). För att klarlägga om förändringarna är reella har dessa ställts mot framtagna naturliga inhomogenitetsfaktorer för respektive ämne i sedimentet.En sammanställning över förändringen av medelvärdeskoncentrationen för några av de mest miljörelevanta ämnena och föreningarna i Stockholms läns kustområdes ytsediment (0-1 cm) mellan 1997-2001 och 2007 visas i nedanstående figur tillsammans med motsvarande förändringar med och utan Stockholm-Mälar-gradienten. Nedåtriktad pil betyder minskad halt och uppåtriktad pil ökad halt. Färgkodningen visar sannolikheten för beräknade förändringar. Av övriga 57 grundämnen som analyserats i sedimentet kan konstateras att under perioden 1997-2001 till 2007 har inom hela skärgårdshavet halten av t.ex. fosfor (P) ökat med 38 % och tenn (Sn) med 261 %. Koncentrationsökningen av fosfor är störst i Stockholm-Mälargradienten (79 %) och beror sannolikt på en ökad fastläggning av fosfor i sedimenten i de områden som fått bottnarna syresatta under 2000-talet.Även tenn uppvisar den största koncentrationsökningen (870 %) i Stockholm-Mälargradienten. Orsakerna till denna ökning är mer svårbedömd, men det är inte osannolikt att källan kan vara båtbottenfärger innehållande de numera förbjudna organiska tennföreningarna, t.ex tributyltenn (TBT). Att dessa föreningar användes efter förbuden har konstaterats i andra undersökningar, men framförallt kan orsaken vara att båtägare skrapat bort dessa färger på upptagningsplatser och ersatt dem med tillåten färg. Den bortskrapade färgen sköljs antingen genom spolning eller med regn (ytavrinning) ut i havet.Koncentrationen av uran (U) och wolfram (W) har ökat med 18 respektive 82 % i Stockholm-Mälar-gradienten. Resultaten tyder på att en källa, berggrundsbetingad eller antropogen finns i Mälaren respektive i centrala Stockholm.Överlagrat dessa förändringar ligger faktorer för inhomogenitet respektive fysiska omblandning (bioturbation) av sedimentet. Den förra faktorn vanligen mindre än 10% och den senare faktorn i genomsnitt 20 % på förändringar som ägt rum under en tioårsperiod respektive 35 % på förändringar som ägt rum under en femårsperiod i oxiderade miljöer. Faktorer som i flera fall är större än de med hög statistisk sannolikhet observerade genomsnittliga koncentrationsförändringarna utmed kusten. I fall med oxiderade bottenförhållanden krävs därför längre observationsperioder, dvs tre till fyra provtagningsomgångar, för att öka säkerheten i slutsatsen över respektive trend. I sediment från anoxiska, dvs miljöer med syrebrist, är inhomogenitetsfaktorn mycket låg och bioturbation saknas. De är den senare typen av bottnar som provtogs 1997-2001 och som valts ut för 2007 års provtagningar.Under senare år har dock en med ballastvatten nyligen invandrad, s.k. främmande art, av havsborstmask (Marenselleria neglecta) invaderat Östersjöns bottnar. Arten kan existera i bottnar med syrebrist (hypoxia; <2 ml syre per liter vatten) och därmed åstadkomma bioturberade ytsediment. Ett förhållande som med röntgenteknik observerats i flera av de sedimentkärnor som provtogs 2007. Detta medför att det föreligger en viss osäkerhet i de observerade trenderna.En säkrare utvecklingstrend, vad avser de olika undersökta ämnena och organiska substanserna, kan därför först erhållas efter ytterligare en till två provtagningsomgångar åtskilda med ett intervall som medger att minst 1-cm nytt sediment ackumulerats på botten sedan den föregående provtagningen. För att utreda provtagningsintervallet har antalet tunna skikt (laminae) räknats och mätts i den radiografiska bilden på respektive sedimentkärna. Beräkningen förutsätter att ett laminae motsvarar ett års ackumulation av sediment.Ackumulationshastigheten har även beräknats genom att mäta aktiviteten för isotopen 137Cs (cesium). Isotopen 137Cs förekommer inte naturligt utan är en antropogent skapadprodukt som uppkommer i samband med kärnklyvningsprocesser. Med beaktande av isotopens 30-åriga halveringstid kan man med stor sannolikhet utgå ifrån att allt 137Cs som idag kan mätas i Östersjöns sediment härrör från Tjernobylolyckan i april 1986. Isotopens nedre gräns för sitt uppträdande i sedimentlagerföljden utgör därmed en s k ”markör” för året 1986. Baserat påvilket sedimentdjup detta sker och de antal år som föflutet mellan Tjernobylolyckan och provtagningsdatum kan ackumulationshastigheten beräknas.De två metoderna ger ett mycket samstämmigt resultat (r2 = 0,88), vilket medför att den beräknade ackumulationshastigheten för respektive station kan betraktas som säker.Det beräknade provtagningsintervallet varierar, beroende på ackumulationshastigheten på respektive station från knappt ett år till drygt tre år. Ett lämpligt provtagningsintervall för en fortsatt miljöövervakning av trenderna i antropogen belastning av metaller och organiska miljögifter är därför med lite säkerhetsmarginal fem år.
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| 16. |
- Frogner-Kockum, Paul, et al.
(författare)
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Less metal fluxes than expected from fibrous marine sediments
- 2020
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 150
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Tidskriftsartikel (refereegranskat)abstract
- © 2019 Deposits of fibrous sediment, which include fiberbanks and fiber-rich sediments, are known to exist on the Swedish seafloor adjacent to coastally located former pulp and paper industries. These deposits contain concentrations of hazardous substances that exceed national background levels and contravene national environmental quality objectives (EQOs). In this study of metal fluxes from fibrous sediments using benthic flux chamber measurements (BFC) in situ we obtained detected fluxes of Co, Mo, Ni and Zn, but no fluxes of Pb, Hg and Cr. The absence of fluxes of some of the analyzed metals indicates particle bound transport of Pb, Cr and Hg from fiberbanks even though Hg might become methylated under anoxic conditions and, in that case, may enter the food chain. We found less metal fluxes than expected and thus emphasize the importance of in-situ flux measurements as a compliment to sediment metal concentrations within risk assessments of contaminated sediments.
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| 17. |
- Josefsson, Sarah, et al.
(författare)
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Miljöföroreningar i utsjösediment – geografiska mönster och tidstrender
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Miljöövervakningen av föroreningar i utsjösediment omfattar organiska föroreningar och grundämnen i ytsediment på 16 stationer på ackumulationsbottnar i havsområdena runt Sverige. Stationerna är placerade i utsjön för att reflektera allmänna föroreningsmönster i miljön. Hittills har provtagning gjorts vid tre år med 5-6 års mellanrum. I denna rapport sammanfattas resultaten och jämförs mellan havs-områdena för att utvärdera geografiska trender och granska potentiella tidstrender.Halterna av arsenik och kobolt är som högst i Bottniska viken, medan halterna av kadmium, koppar och zink är högst i Egentliga Östersjön; kadmiumhalterna är så höga att den effektbaserade bedömnings-grunden överskrids. Dessa mönster beror på redoxförhållanden och belastning från berggrund och punktkällor. Halterna av bly och kvicksilver är istället förhöjda på specifika stationer, vilket tyder på ett större inflytande från punktkällor. Metallhalterna är fortfarande förhöjda överlag i förhållande till jämförvärden som representerar förindustriella halter.Den största belastningen av organiska föroreningar förekommer i Egentliga Östersjön och i södra delarna av Östersjön. För flertalet ämnen är halterna som högst här, t.ex. summa DDT, PCB, dioxiner, PAH, klorparaffiner, ftalater och oktyl/nonylfenoler. Halterna av TBT har minskat sedan 2003 men bedömningsgrunden överskrids fortfarande i Egentliga Östersjön och södra Östersjön och halterna tycks inte längre minska på stationerna i södra Östersjön. Halterna av cybutryn är högst i Egentliga Östersjön där de ökat mellan 2008 och 2014. Cybutryn får inte längre användas i båtbottenfärger inom EU vilket bör ge en effekt på halterna i framtiden. Halterna av den sedan länge förbjudna pesticiden HCB har ökat på många stationer, inte minst mellan 2008 och 2014 på stationer med snabb sedimentackumulations-hastighet vilket tyder på en haltökning i den akvatiska miljön.
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| 18. |
- Löfroth, Hjördis, et al.
(författare)
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Challenges in slope stability assessment of contaminated fibrous sediments along the northern Baltic coast of Sweden
- 2021
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Ingår i: Engineering Geology. - : Elsevier BV. - 0013-7952 .- 1872-6917. ; 289
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Tidskriftsartikel (refereegranskat)abstract
- In several locations along Sweden's northern Baltic coast there are deposits of contaminated fibrous sediments that are known as fiberbanks. Historically, these anthropogenic fiberbanks and associated contaminants were formed outside pulp and paper factories because of unregulated waste discharges. Some of the fiberbanks are located on seafloor slopes that are unstable and may fail, which could result in large amounts of fiber and contaminant dispersion. Hydroacoustic surveys have revealed that some parts of the fiberbanks have been dispersed to a wider area by submarine landslides. However, the unusual nature of these cellulose-rich sediments makes it difficult to apply conventional techniques for assessing submarine slope stability. Therefore, a combination of investigation techniques and interpretation methods was tested to assess the stability and triggering mechanisms for submarine slope failure identified in fiberbanks from the Ångermanälven river estuary on the Baltic sea coast. The integration of bathymetric data, sediment lithology and geotechnical characteristics from in-situ and laboratory measurements, enabled the characterisation of underlying natural sediments and the fiberbanks at two sites. Despite low densities, which indicate that the fiberbank material is near the buoyancy level, the fiberbank deposits seem to be relatively stable. Our results indicate the underlying natural sediments are also stable and would require an external triggering mechanism to generate the observed slope failures. We suggest that pore water pressure, potentially related to groundwater table fluctuations, may be an important trigger for submarine landslides in the study area.Management of fiberbanks and associated fiber-rich sediments, which are numerous along Sweden's north east coast, requires that sites are risk assessed and prioritized for remediation. To do so, under water slope stability should be considered as a possible dispersion pathway and therefore needs to be investigated. The study illustrates the value of using a combination of geophysical and geotechnical field and laboratory methods, together with empirical relationships, to assess relevant input parameters for slope stability calculations for this type of sediment.
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| 19. |
- Rydin, Emil, et al.
(författare)
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Contrasting distribution and speciation of sedimentary organic phosphorus among different basins of the Baltic Sea
- 2023
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Ingår i: Limnology and Oceanography. - : John Wiley & Sons. - 0024-3590 .- 1939-5590. ; 68:4, s. 767-779
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Tidskriftsartikel (refereegranskat)abstract
- Recycling of phosphorus (P) from deoxygenated sediments perpetuates eutrophic conditions in parts of the Baltic Sea. Sedimentary organic P is a major source of dissolved P to the water column, but also a sink for permanent P burial. The mechanisms behind these two pathways are, however, largely unknown. Using new methods, we determined P in DNA and phospholipids, which are both found in all organisms. We also identified inositol phosphates that are particularly important in eukaryotes. Sediment cores were collected from contrasting basins in the Baltic Sea to study their relative contribution to the total P pool. We found high DNA-P/phospholipid-P ratios in surface sediments from the Bothnian Bay and Bothnian Sea. However, these ratios were low throughout profiles in euxinic Baltic Proper sediments. The elevated ratios present in sediments overlain by oxic bottom waters might indicate the presence of a microbial community stimulated by bioturbation, whereas the low DNA-P/phospholipid-P ratios in Baltic Proper sediments likely indicate an energy-limited microbial community, typical to the "deep biosphere" environment. Inositol-P was almost absent in euxinic Baltic Proper sediments that had a low total P amount compared to those in the other basins. We suggest that variability in the composition of sedimentary microbial communities among the Baltic Sea basins might cause differences in organic P forms that in turn affects its turnover.
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| 20. |
- Shahabi-Ghahfarokhi, Sina, et al.
(författare)
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Background concentrations and extent of Cu, As, Co, and U contamination in Baltic Sea sediments
- 2021
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Ingår i: Journal of Sea Research. - : Elsevier. - 1385-1101 .- 1873-1414. ; 176
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Tidskriftsartikel (refereegranskat)abstract
- This study established background (pre-industrial) values of copper (Cu), arsenic (As), cobalt (Co), and uranium (U) in Baltic Sea sediments. The indicated background values could help identifying the spatial and temporal anthropogenic loads of these elements (metals and metalloids) in the Baltic Sea. In this study, 137 sediment samples were collected from cores obtained from 13 monitoring stations in the Gulf of Bothnia (Bothnian Bay and Sea) and the entire Baltic Proper. To understand the extent of contamination, we used direct and combined methods to define the geochemical background values as inputs for the geochemical index (Igeo) calculation. The obtained values were then compared with the background values established by the Swedish Environmental Protection Agency. From the direct method, Cu, Co, As, and U had background values of 39, 21.5, 12.4, and 6.3 mg kg−1 DW. Copper and U exhibited concentrations above the background values in surface sediment in the western and eastern Baltic Proper (maximum Igeo indicates moderate contamination). Arsenic was above background concentrations in the Baltic Sea and highest in the Gulf of Bothnia (maximum Igeo indicates strong contamination). Cobalt concentrations were within the range of background values (no contamination).
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| 21. |
- Shahabi-Ghahfarokhi, Sina, et al.
(författare)
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Baltic Sea sediments record anthropogenic loads of Cd, Pb, and Zn
- 2021
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Ingår i: Environmental Science and Pollution Research. - : Springer. - 0944-1344 .- 1614-7499. ; 28, s. 6162-6175
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Tidskriftsartikel (refereegranskat)abstract
- The unsustainable settlement and high industrialization around the catchment of the Baltic Sea has left records of anthropogenic heavy metal contamination in Baltic Sea sediments. Here, we show that sediments record post-industrial and anthropogenic loads of Cd, Zn, and Pb over a large spatial scale in the Baltic Sea. We also demonstrate that there is a control on the accumulation of these metals in relation to oxic/anoxic conditions of bottom waters. The total concentrations of Cd, Zn, and Pb were obtained with the near-total digestion method in thirteen cores collected from the Bothnian Bay, the Bothnian Sea, and the west and central Baltic Proper. The lowest average concentrations of Cd, Zn, and Pb were observed in Bothnian Bay (0.4, 125, 40.2 mg kg−1 DW, respectively). In contrast, the highest concentrations were observed in the west Baltic Proper (5.5, 435, and 56.6 mg kg−1 DW, respectively). The results indicate an increasing trend for Cd, Zn, and Pb from the early nineteenth century until the 1970s, followed by a decrease until 2000–2008. However, surface sediments still have concentrations above the pre-industrial values suggested by the Swedish EPA (Cd is 0.2, Zn is 85, and Pb is 31 mg kg−1 DW). The results also show that the pre-industrial Cd, Zn, and Pb concentrations obtained from 3 cores with ages < 1500 B.C. were 1.8, 1.7, and 1.2 times higher, respectively, than the pre-industrial values suggested by the Swedish EPA. To conclude, accumulations of metals in the Baltic Sea are governed by anthropogenic load and the redox conditions of the environment. The significance of correct environmental governance (measures) can be illustrated with the reduction in the pollution of Pb, Zn, and Cd within the Baltic Sea since the 1980s.
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| 22. |
- Snowball, Ian, 1963-, et al.
(författare)
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Till botten med gamla synder
- 2015
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Ingår i: Havsutsikt. - : Stockholms universitet, Umeå universitet. - 1104-0513. ; :2, s. 18-20
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 23. |
- Tengberg, Anders, 1962, et al.
(författare)
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Sustainable management of oil polluting wrecks and chemical munitions dump sites
- 2017
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Ingår i: OCEANS 2017 - ABERDEEN. - 0197-7385. - 9781509052783 ; 2017-October
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Konferensbidrag (refereegranskat)abstract
- Dumped chemical weapons that are corroding and exposed to the marine environment can cause contamination and health risks for marine fauna and humans. This paper describes some of the work that is done in the EU-DAIMON (Decision Aid for Marine Munitions) project including the development of a decision support method and previous field results that indicate that bottom trawling re-suspend sediments and spread contaminants and that recently caught fish at the Maseskar dump site contains detectable concentrations of chemical weapons from World War II.
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