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Polybrominated diphenyl ethers (PBDEs) and alternative brominated flame retardants in air and seawater of the European Arctic
2011
Möller, Axel | Xie, Zhiyong | Sturm, Renate | Ebinghaus, Ralf
The spatial distribution of polybrominated diphenyl ethers (PBDEs) and several alternative non-PBDE, non-regulated brominated flame retardants (BFRs) in air and seawater and the air–seawater exchange was investigated in East Greenland Sea using high-volume air and water samples. Total PBDE concentrations (Ó₁₀PBDEs) ranged from 0.09 to 1.8 pg m⁻³ in the atmosphere and from 0.03 to 0.64 pg L⁻¹ in seawater. Two alternative BFRs, Hexabromobenzene (HBB) and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE), showed similar concentrations and spatial trends as PBDEs. The air–seawater gas exchange was dominated by deposition with fluxes up to −492 and −1044 pg m⁻² day⁻¹ for BDE-47 and DPTE, respectively. This study shows the first occurrence of HBB, DPTE and other alternative flame retardants (e.g., pentabromotoluene (PBT)) in the Arctic atmosphere and seawater indicating that they have a similar long-range atmospheric transport potential (LRAT) as the banned PBDEs.
Afficher plus [+] Moins [-]Cell size dependence of additive versus synergetic effects of UV radiation and PAHs on oceanic phytoplankton
2011
Echeveste, Pedro | Agustí, Susana | Dachs, Jordi
Polycyclic Aromatic Hydrocarbons’ (PAHs) toxicity is enhanced by the presence of ultraviolet radiation (UVR), which levels have arisen due to the thinning of the ozone layer. In this study, PAHs’ phototoxicity for natural marine phytoplankton was tested. Different concentrations of a mixture of 16 PAHs were added to natural phytoplankton communities from the Mediterranean Sea, Atlantic, Arctic and Southern Oceans and exposed to natural sunlight received in situ, including treatments where the UVR bands were removed. PAHs’ toxicity was observed for all the phytoplankton groups studied in all the waters and treatments tested, but only for the pico-sized group a synergetic effect of the mixture and UVR was observed (p=0.009). When comparing phototoxicity in phytoplankton from oligotrophic and eutrophic waters, synergy was only observed at the oligotrophic communities (p=0.02) where pico-sized phytoplankton dominated. The degree of sensitivity was related to the trophic degree, decreasing as Chlorophyll a concentration increased.
Afficher plus [+] Moins [-]Biomarker responses associated with halogenated organic contaminants in northern fulmars (Fulmarus glacialis) breeding in the Canadian Arctic
2011
Braune, Birgit M. | Trudeau, Suzanne | Jeffrey, Deborah A. | Mallory, Mark L.
We examined relationships between hepatic concentrations of halogenated organic contaminants and ethoxyresorufin O-deethylase (EROD) activity and retinoid (vitamin A) concentrations in livers, as well as retinol and thyroid hormone (TT₃, TT₄) levels in blood plasma, of northern fulmars at two breeding colonies in the Canadian High Arctic. Biomarker levels or responses did not differ significantly between males and females at either colony, nor was there any significant difference between colonies. No significant relationships were found between thyroid hormone or hepatic retinoid concentrations and any of the dioxin-like compounds or their Toxic Equivalents (TEQs) although significant positive correlations were found with plasma retinol (p < 0.03). EROD activity was significantly correlated with hepatic dioxin-like compounds and their TEQs (p < 0.001) as well as total PCBs (p < 0.01), which suggests that EROD induction occurs in northern fulmars at environmentally-relevant concentrations.
Afficher plus [+] Moins [-]Assessment of the environmental persistence and long-range transport of endosulfan
2011
Becker, Linus | Scheringer, Martin | Schenker, Urs | Hungerbühler, Konrad
Concentrations of the insecticide endosulfan (α- and β-isomer) and its degradation product endosulfan sulfate in air, seawater and soil are calculated with the global environmental fate model CliMoChem. As model input, physicochemical properties of all three compounds were assembled and a latitudinally and temporally resolved emission inventory was generated. For concentrations in air, model and measurements are in good agreement; a bimodal seasonality with two peaks in spring and fall as it is observed in Arctic air is reproduced by the model. For seawater, the agreement of model and measurements depends on the values of the hydrolysis activation energy of endosulfan used in the model; with relatively high values around 100kJ/mol, model results match field data well. The results of this assessment of the levels, persistence, and global distribution of endosulfan are also relevant for the evaluation of endosulfan as a Persistent Organic Pollutant under the Stockholm Convention.
Afficher plus [+] Moins [-]Organophosphorus flame retardants and plasticizers in the atmosphere of the North Sea
2011
Möller, Axel | Xie, Zhiyong | Caba, Armando | Sturm, Renate | Ebinghaus, Ralf
Air samples collected in the German part of the North Sea from March to July 2010 were investigated for organophosphorus compounds (OPs) being applied as flame retardants and plasticizers. The ∑₈OPs concentration ranged from 110 to 1400 pg m⁻³ while tris(2-chloroisopropyl) phosphate (TCPP) dominated all samples with individual concentrations up to 1200 pg m⁻³. The highest concentrations were observed in continental air masses showing the high influence of industrialized regions including production sites on atmospheric emissions and concentrations. The occurrence of OPs even in oceanic/Arctic air masses shows that OPs can undergo long-range atmospheric transport. Dry particle-bound deposition fluxes from 9 to 240 ng m⁻² d⁻¹ for ∑₈OPs were estimated leading to a minimum annual flux of 710 ± 580 kg y⁻¹ OPs into the German North Sea. This study presents the first occurrence of OPs in the marine atmosphere together with important information on their long-range transport potential.
Afficher plus [+] Moins [-]Environmental toxicology: Population modeling of cod larvae shows high sensitivity to loss of zooplankton prey
2011
Stige, Leif Christian | Ottersen, Geir | Hjermann, Dag Ø | Dalpadado, Padmini | Jensen, Louise K. | Stenseth, Nils Chr
Two factors determine whether pollution is likely to affect a population indirectly through loss of prey: firstly, the sensitivity of the prey to the pollutants, and secondly, the sensitivity of the predator population to loss of prey at the given life stage. We here apply a statistical recruitment model for Northeast Arctic cod to evaluate the sensitivity of cod cohorts to loss of zooplankton prey, for example following an oil spill. The calculations show that cod cohorts are highly sensitive to possible zooplankton biomass reductions in the distribution area of the cod larvae, and point to a need for more knowledge about oil-effects on zooplankton. Our study illustrates how knowledge about population dynamics may guide which indirect effects to consider in environmental impact studies.
Afficher plus [+] Moins [-]Measuring ignitability for in situ burning of oil spills weathered under Arctic conditions: From laboratory studies to large-scale field experiments
2011
Fritt-Rasmussen, Janne | Brandvik, Per Johan
This paper compares the ignitability of Troll B crude oil weathered under simulated Arctic conditions (0%, 50% and 90% ice cover). The experiments were performed in different scales at SINTEF’s laboratories in Trondheim, field research station on Svalbard and in broken ice (70–90% ice cover) in the Barents Sea. Samples from the weathering experiments were tested for ignitability using the same laboratory burning cell. The measured ignitability from the experiments in these different scales showed a good agreement for samples with similar weathering. The ice conditions clearly affected the weathering process, and 70% ice or more reduces the weathering and allows a longer time window for in situ burning. The results from the Barents Sea revealed that weathering and ignitability can vary within an oil slick. This field use of the burning cell demonstrated that it can be used as an operational tool to monitor the ignitability of oil spills.
Afficher plus [+] Moins [-]Content and distribution of trace metals in surface sediments from the northern Bering Sea, Chukchi Sea and adjacent Arctic areas
2011
Cai, M.H. | Lin, J. | Hong, Q.Q. | Wang, Y. | Cai, M.G.
Concentrations of trace metals (Zn, Cr, Cu, V, Cd and Pb), total organic carbon (TOC), black carbon (BC) and their granulometry were examined in 25 surface sediment samples from the northern Bering Sea, Chukchi Sea and adjacent areas. Trace metal concentrations in the sediments varied from 21.06–168.21mgkg⁻¹ for Zn, 8.91–46.94mgkg⁻¹ for Cr, 2.69–49.39mgkg⁻¹ for Cu, 32.46–185.54mgkg⁻¹ for V, 0.09–0.92mgkg⁻¹ for Cd, and 0.95–15.25mgkg⁻¹ for Pb. The geoaccumulation index (Igₑₒ) indicated that trace metal contamination (Zn and Cd) existed in some stations of the study area. The distribution of grain size plays an important role in influencing the distribution of trace metals (Zn, Cr, Cu, V, and Pb) in sediments from the Chukchi Sea and adjacent areas.
Afficher plus [+] Moins [-]Mercury (Hg) Transport in a High Arctic River in Northeast Greenland
2011
Rigét, Frank | Tamstorf, Mikkel P. | Larsen, Martin M. | Søndergaard, Jens | Asmund, Gert | Falk, Julie Maria | Sigsgaard, Charlotte
In a warming climate, mercury (Hg) pathways in the Arctic can be expected to be affected. The Hg transport from the high arctic Zackenberg River Basin was assessed in 2009 in order to describe and estimate the mercury transported from land to the marine environment. A total of 95 water samples were acquired and filtered (0.4 μm pore size), and Hg concentrations were determined in both the filtered water and in the sediment. A range of other elements were also measured in the water samples. Hg concentrations in the filtered water were in general highest in the beginning of the season when the water came mainly from melted snow. THg concentrations in the sediment were in general relatively constant or slightly decreasing until mid-August, where after the concentrations increased. A principal component analysis separated the samples into spring, summer and autumn samples indicating seasonal characteristics of the patterns of element concentrations. The total amount of Hg in the sediment transported was estimated to 2.6 kg. Approximately 60% of the sediment-transported Hg occurred during a 24-h flood in the beginning of August caused by a glacial lake outburst flood. The total amount of transported dissolved Hg was estimated to 46 g, and 13% of this transport occurred during the 24-h flood. If it is assumed that the Hg transport by Zackenberg River is representative for the general glacial rivers in East Greenland, the total Hg transport into the North Atlantic from Greenland alone is approximately 4.6 tons year−1 with an estimated annual freshwater discharge of â¼440 km3.
Afficher plus [+] Moins [-]Do metal concentrations in moss from the Zackenberg area, Northeast Greenland, provide a baseline for monitoring?
2011
Zechmeister, Harald G. | Dullinger, Stefan | Koellensperger, Gunda | Ertl, Siegrun | Lettner, Christian | Reiter, Karl
PURPOSE: This study aims at evaluating (a) whether concentrations of a suite of elements in mosses sampled in the arctic region around Zackenberg reflect background concentrations useful for estimating pollution levels in industrialized parts of the northern hemisphere as is attempted, e.g. in the framework of the UNECE ICP Vegetation monitoring programme, and (b) whether there are any influences from Zackenberg research station detectable in these concentrations. METHODS: Two moss species were sampled according to guidelines used in the UNECE ICP Vegetation programme. Samples were analysed for ¹⁹⁵Pt at low resolution, ²⁷Al, ⁵²Cr, ⁶⁵Cu, ⁶⁶Zn, ⁹⁵Mo, ¹¹¹Cd, ¹¹⁸Sn, ¹²¹Sb and ²⁰⁸Pb at medium resolution and ⁷⁵As at high resolution on an Element 2 inductively coupled plasma sector field mass spectrometer. RESULTS: Except for Al, As and Cr, data from Zackenberg showed significantly lower mean element concentrations than those reported in comparable studies from all over the world including those from other Arctic environments. Minimum concentrations in Zackenberg mosses were consistently below all values reported so far for all elements analysed. The results of a PCA suggested only a slight impact from Zackenberg research station on concentrations of Cd, Mo and Zn in moss. CONCLUSIONS: We conclude that the sites in Zackenberg can be considered true background sites providing baseline concentrations of at least eight elements for comparable monitoring studies.
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