| 1. |
- Andersson Trojer, Markus, 1981, et al.
(författare)
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Imidazole and Triazole Coordination Chemistry for Antifouling Coatings
- 2013
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Ingår i: Journal of Chemistry. - : Hindawi Limited. - 2090-9063 .- 2090-9071. ; 2013
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Tidskriftsartikel (refereegranskat)abstract
- Fouling of marine organisms on the hulls of ships is a severe problem for the shipping industry. Many antifouling agents are based on five-membered nitrogen heterocyclic compounds, in particular imidazoles and triazoles. Moreover, imidazole and triazoles are strong ligands for Cu2+ and Cu+, which are both potent antifouling agents. In this review, we summarize a decade of work within our groups concerning imidazole and triazole coordination chemistry for antifouling applications with a particular focus on the very potent antifouling agent medetomidine. The entry starts by providing a detailed theoretical description of the azole-metal coordination chemistry. Some attention will be given to ways to functionalize polymers with azole ligands. Then, the effect of metal coordination in azole-containing polymers with respect to material properties will be discussed. Our work concerning the controlled release of antifouling agents, in particular medetomidine, using azole coordination chemistry will be reviewed. Finally, an outlook will be given describing the potential for tailoring the azole ligand chemistry in polymers with respect to Cu2+ adsorption and Cu2+ Cu+ reduction for antifouling coatings without added biocides.
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| 2. |
- Dahlbäck, Björn, et al.
(författare)
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The Challenge to Find New Sustainable Antifouling Approaches for Shipping
- 2010
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Ingår i: Coastal Marine Science. - 1349-3000. ; 34:1, s. 212-215
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Fouling of ships and its counter measure – antifouling – is receiving justified attention as a serious marine environmental problem. If the ship is fouled its fuel consumption will increase radically. If a ship is fouled its emissions to air will increase, its manoeuvrability will be affected and it will contribute to the spreading of aliens. The present antifouling strategies seem to be non-sustainable, either environmentally or technically/commercially. The large amounts of biocides used in antifouling paints constitute a marine pollution problem. Research for more sustainable solutions, biocidal as well as non-biocidal, is ongoing. Optimisation of new antifoulant combinations combined with microcapsule technology will offer the possibility to decrease the exposure of the marine environment to antifouling biocides.
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| 3. |
- Eriksson, Martin, 1970, et al.
(författare)
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Long-term effects of lowered pH on marine periphyton communities
- 2011
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Ingår i: SETAC (Society of environmental Toxicology and Chemistry) Europe, 21st Annual Meeting.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The phenomenon of Ocean Acidification has been identified as a potential threat to several marine organisms and might lead to adverse disturbances of marine ecosystems. Although the knowledge about effects of rising acidity in the oceans is increasing for some species, the knowledge of these effects on the community level of biological complexity is very scarce. Still, community-level effect indicators are needed in order to predict direct and indirect effects of Ocean Acidification on marine ecosystems. In a community the organisms live in their realized niche with important ecological interactions (e.g. competition, grazing and predation) present. This gives community approaches in ecotoxicological tests high ecological relevance. Since lowered pH might eliminate species or strains that are sensitive to such stress, and select for the ones that are more competitive under this condition, a community approach have the potential to detect any pH-induced change in community structure or function. We have used marine periphyton communities in a long-term study of effects of increased partial pressure of CO2 in the water and the accompanied lowering of pH. Periphyton was allowed to colonize and grow on glass substrata for 3.5 weeks in flow-through microcosms. The pH in the microcosms was either that of the incoming natural surface water or was manipulated by bubbling of CO2 down to approximately 7.7. We used Pulse Amplitude Modulation (PAM) to detect effects on photosynthetic electron transport and estimate induced community tolerance to low pH. In addition, we used confocal microscopy to trace effects on biofilm architecture and biofilm thickness. We have also estimated microbial diversity and composition of trace elements in periphyton using PCR-TGGE and X-ray fluorescence respectively. First results indicate that long-term effects of lowered pH change the capacity of communities to tolerate further changes in pH, making them more sensitive to pH-stress. However, no long-term effects on photosynthetic electron transport or trace element composition was detected.
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| 4. |
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| 5. |
- Johansson, P., et al.
(författare)
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Effects of Seven Antifouling Compounds on Photosynthesis and Inorganic Carbon Use in Sugar Kelp Saccharina latissima (Linnaeus)
- 2012
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Ingår i: Archives of Environmental Contamination and Toxicology. - : Springer Science and Business Media LLC. - 0090-4341 .- 1432-0703. ; 63:3, s. 365-377
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Tidskriftsartikel (refereegranskat)abstract
- Macroalgae depend on carbon-concentrating mechanisms (CCMs) to maintain a high photosynthetic activity under conditions of low carbon dioxide (CO2) availability. Because such conditions are prevalent in marine environments, CCMs are important for upholding the macroalgal primary productivity in coastal zones. This study evaluated the effects of seven antifouling compounds-chlorothalonil, DCOIT, dichlofluanid, diuron, irgarol, tolylfluanid, and zinc pyrithione (ZnTP)-on the photosynthesis and CCM of sugar kelp (Saccharina latissima (L.)). Concentration-response curves of these toxicants were established using inhibition of carbon incorporation, whereas their effects over time and their inhibition of the CCM were studied using inhibition of O-2 evolution. We demonstrate that exposure to all compounds except ZnTP (< 1000 nM) resulted in toxicity to photosynthesis of S. latissima. However, carbon incorporation and O-2 evolution differed in their ability to detect toxicity from some of the compounds. Diuron, irgarol, DCOIT, tolylfluanid, and, to some extent, dichlofluanid inhibited carbon incorporation. Chlorothalonil did not inhibit carbon incorporation but clearly inhibited oxygen (O-2) evolution. Photosynthesis showed only little recovery during the 2-h postexposure period. Inhibition of photosynthesis even increased after the end of exposure to chlorothalonil and tolylfluanid. Through changes in pH of the medium, toxic effects on the CCM could be studied isolated from photosynthesis effects. The CCM of S. latissima was inhibited by chlorothalonil, DCOIT, dichlofluanid, and tolylfluanid. Such inhibition of the CCM, or the absence thereof, deepens the understanding the mechanism of action of the studied compounds.
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| 6. |
- Ohlauson, Cecilia, et al.
(författare)
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Short-term effects of medetomidine on photosynthesis and protein synthesis in periphyton, epipsammon and plankton communities in relation to predicted environmental concentrations
- 2012
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Ingår i: Biofouling. - : Informa UK Limited. - 0892-7014 .- 1029-2454. ; 28:5, s. 491-499
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Tidskriftsartikel (refereegranskat)abstract
- Medetomidine is a new antifouling substance, highly effective against barnacles. As part of a thorough ecotoxicological evaluation of medetomidine, its short-term effects on algal and bacterial communities were investigated and environmental concentrations were predicted with the MAMPEC model. Photosynthesis and bacterial protein synthesis for three marine communities, viz. periphyton, epipsammon and plankton were used as effect indicators, and compared with the predicted environmental concentrations (PECs). The plankton community showed a significant decrease in photosynthetic activity of 16% at 2 mg l(-1) of medetomidine, which was the only significant effect observed. PECs were estimated for a harbor, shipping lane and marina environment using three different model scenarios (MAMPEC default, Baltic and OECD scenarios). The highest PEC of 57 ng l(-1), generated for a marina with the Baltic scenario, was at least 10,000-fold lower than the concentration that significantly decreased photosynthetic activity. It is concluded that medetomidine does not cause any acute toxic effects on bacterial protein synthesis and only small acute effects on photosynthesis at high concentrations in marine microbial communities. It is also concluded that the hazard from medetomidine on these processes is low since the effect levels are much lower than the highest PEC.
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