| 1. |
- Selck, H., et al.
(författare)
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Assessing and managing multiple risks in a changing worldThe Roskilde recommendations
- 2017
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Ingår i: Environmental Toxicology and Chemistry. - Hoboken, NJ : Wiley. - 0730-7268 .- 1552-8618. ; 36:1, s. 7-16
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Tidskriftsartikel (refereegranskat)abstract
- Roskilde University (Denmark) hosted a November 2015 workshop, Environmental RiskAssessing and Managing Multiple Risks in a Changing World. This Focus article presents the consensus recommendations of 30 attendees from 9 countries regarding implementation of a common currency (ecosystem services) for holistic environmental risk assessment and management; improvements to risk assessment and management in a complex, human-modified, and changing world; appropriate development of protection goals in a 2-stage process; dealing with societal issues; risk-management information needs; conducting risk assessment of risk management; and development of adaptive and flexible regulatory systems. The authors encourage both cross-disciplinary and interdisciplinary approaches to address their 10 recommendations: 1) adopt ecosystem services as a common currency for risk assessment and management; 2) consider cumulative stressors (chemical and nonchemical) and determine which dominate to best manage and restore ecosystem services; 3) fully integrate risk managers and communities of interest into the risk-assessment process; 4) fully integrate risk assessors and communities of interest into the risk-management process; 5) consider socioeconomics and increased transparency in both risk assessment and risk management; 6) recognize the ethical rights of humans and ecosystems to an adequate level of protection; 7) determine relevant reference conditions and the proper ecological context for assessments in human-modified systems; 8) assess risks and benefits to humans and the ecosystem and consider unintended consequences of management actions; 9) avoid excessive conservatism or possible underprotection resulting from sole reliance on binary, numerical benchmarks; and 10) develop adaptive risk-management and regulatory goals based on ranges of uncertainty. Environ Toxicol Chem 2017;36:7-16. (c) 2016 SETAC
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| 2. |
- Granberg, Maria E., 1971, et al.
(författare)
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Relative importance of macrofaunal burrows for the microbial mineralization of pyrene in marine sediments: impact of macrofaunal species and organic matter quality
- 2005
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Ingår i: Marine Ecology-Progress Series. - : Inter-Research Science Center. - 0171-8630 .- 1616-1599. ; 288, s. 59-74
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Tidskriftsartikel (refereegranskat)abstract
- The significance of macrofaunal burrows for microbial organic matter mineralization is well recognized. However, despite the importance of marine sediments as main sinks for organic particle-reactive contaminants such as polyaromatic hydrocarbons (PAHs), the significance of biogenic structures for microbial pollutant mineralization is largely unknown. We measured microbial mineralization of the PAH pyrene in different sediment compartments (surface, burrow and reduced bulk sediments) as a function of contamination history (uncontaminated and pyrene-exposed), macrofaunal species (Amphiura filiformis and Nereis diversicolor) and sediment organic matter quality (labile Tetraselmis sp. and refractory lignin). Sediments were exposed to combinations of the 3 factors for 43 d, after which sediment samples from the 3 compartments were incubated for radio-respirometric measurements in C-14-pyrene-coated flasks to monitor (CO2)-C-14 production (i.e. pyrene mineralization) for 128 d. Pyrene exposure enhanced microbial pyrene mineralization (MPM) rates by an order of magnitude in all compartments, signifying MPM as inducible. MPM rates increased successively from reduced bulk to burrow and surface sediments in uncontaminated treatments, while MPM rates were highest in burrows when exposed to pyrene. This emphasizes the oxygen dependence of MPM and pinpoints burrows as MPM hot spots. Enrichment with labile organic matter doubled MPM rates in pyrene-exposed surface sediment, likely fertilizing MPM where oxygen is readily available. Burrow sediment MPM rates were doubled with A, filiformis, suggesting species-specific stimulation of the microbial community within the burrows. In conclusion, burrow sediment appears to be at least as important as surface sediment for microbial PAH degradation in marine sediments. Furthermore, macrofaunal biodiversity, sedimentation events and the trophic state of the system should be taken into account when the fate and effects of organic contaminants are assessed in marine systems.
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| 3. |
- Lammel, Tobias, et al.
(författare)
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Trophic transfer of CuO NPs and dissolved Cu from sediment to worms to fish-a proof-of-concept study
- 2019
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Ingår i: Environmental Science: Nano. - : Royal Society of Chemistry (RSC). - 2051-8153 .- 2051-8161. ; 6:4, s. 1140-1155
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Tidskriftsartikel (refereegranskat)abstract
- Man-made nanoparticles (NPs) released into the aquatic environment are likely to accumulate in sediment. Uptake of NPs by benthic invertebrates that serve as food for higher trophic level organisms such as fish may result in their transfer along the food chain. We tested this hypothesis in a proof-of-concept approach consisting of two studies examining the transfer of copper(ii) oxide NPs (CuO NPs) (<50 nm) and dissolved copper (CuCl 2 ). Study 1 focussed on transfer from sediment to worms (Tubifex tubifex) and study 2 on transfer from worms (T. tubifex) to fish (Gasterosteus aculeatus, three-spined stickleback). A key methodological achievement of study 2 was the development of worm homogenate-based food packages, which allowed controlling CuO NPs and CuCl 2 dosing of fish. In T. tubifex, no significant differences in Cu accumulation were detected following 7 days of exposure to sediment-associated CuO NPs or CuCl 2 (100 μg Cu per g dw sediment). Yet, metallothionein-like protein levels were significantly elevated in CuO NP-exposed worms compared to the control, while they were not in CuCl 2 -exposed worms. G. aculeatus fed CuO NP- A nd CuCl 2 -spiked food packages (2 μg Cu per g fish ww per day; 7 days) showed increased Cu concentrations (∼13 and ∼31 μg Cu per g dw compared to control, respectively) and metallothionein (mta) mRNA expression in intestinal tissue. In CuO NP-exposed fish, Cu and mta mRNA levels were noticeably lower than in CuCl 2 -exposed fish and inversely correlated with the amount of Cu in their faeces, suggesting that a large fraction of NPs was egested. Altogether, the results suggest that sediment-associated CuO NPs can enter the aquatic food web, but that transfer of CuO NPs from T. tubifex to stickleback may be limited compared to dissolved Cu. Furthermore, there were no indications of induction of oxidative stress in fish intestine and liver, suggesting that effects from environmentally relevant Cu/CuO NP exposure via the diet may be minimal. © 2019 The Royal Society of Chemistry.
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| 4. |
- Lammel, Tobias, et al.
(författare)
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Trophic transfer of CuO NPs from sediment to worms (Tubifex tubifex) to fish (Gasterosteus aculeatus): a comparative study of dissolved Cu and NPs enriched with a stable isotope tracer (Cu-65)
- 2020
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Ingår i: Environmental Science-Nano. - : Royal Society of Chemistry (RSC). - 2051-8153 .- 2051-8161. ; 7:8, s. 2360-2372
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Tidskriftsartikel (refereegranskat)abstract
- Metal nanoparticles (NPs) released into the aquatic environment will likely accumulate in sediment and be available for sediment-dwelling invertebrates that serve as food for other organisms, such as fish. The aim of the present study was to investigate trophic transfer of copper oxide (CuO) NPs and dissolved Cu (CuCl2) from natural sediment to the sediment-dwelling worm Tubifex tubifex, and then to the predatory fish Gasterosteus aculeatus (three-spined stickleback). Cu enriched in the stable isotope Cu-65 was used to increase detection and discriminate newly added/assimilated Cu from background Cu levels. Worms were exposed to sediment spiked with (CuCl2)-Cu-65 or (CuO)-Cu-65 NPs (similar to 20 nm) at environmentally relevant concentrations for 7 days and subsequently fed to fish for 7 days. Worms accumulated Cu-65 during sediment exposure to both (CuCl2)-Cu-65 and (CuO)-Cu-65 NPs (0.7 and 1.1 mu g Cu-65 per g dw tissue, respectively), resulting in Cu-65 body burdens significantly different from control. Furthermore, significantly more Cu-65 was released from the sediment into the overlying water in the 65 CuO NP exposures compared to the (CuCl2)-Cu-65 exposures. Cu-65 accumulation in fish feeding on (CuCl2)-Cu-65 and (CuO)-Cu-65 NP-exposed worms was limited (intestinal tissue: 80 and 65 ng g(-1) dw; fish carcass: 7 and 10 ng g(-1) dw, and liver: 50 and 10 ng g(-1) dw, respectively). Glutathione peroxidase (gpx) mRNA expression was significantly higher in fish feeding on (CuCl2)-Cu-65-exposed worms compared to (CuO)-Cu-65 NP-exposed worms (though Cu-65 tissue concentrations were similar). No significant effects were detected for the other investigated genes (ctr1, mta, gcl, gr, sod, cat, zo-1). Our results show that NP-derived Cu can enter freshwater food webs, but bioaccumulation and trophic transfer under environmentally realistic exposures is low (detectable with a tracer) and not different from that of dissolved Cu.
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| 5. |
- Selck, H., et al.
(författare)
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Impact of sediment organic matter quality on the fate and effects of fluoranthene in the infaunal brittle star Amphiura filiformis
- 2005
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Ingår i: Marine Environmental Research. - : Elsevier BV. - 0141-1136. ; 59:1, s. 19-45
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Tidskriftsartikel (refereegranskat)abstract
- Hydrophobic contaminants, such as polycyclic aromatic hydrocarbons (PAHs) readily adsorb to organic matter. The aim of this study was to determine the importance of the quality of sedimentary organic matter for the uptake, biotransformation and toxicity of the PAH, fluoranthene (Flu), in the infaunal brittle star Amphiura filiformis. Brittle stars were exposed to a base sediment covered by a 2 cm Flu-spiked top layer (30 mug Flu/g dry wt. sed.), enriched to the same total organic carbon content with either refractory or labile organic matter. The labile carbon source was concentrated green flagellate: Tetraselmis spp. The refractory carbon source was lignin from a paper mill. Tissue concentrations of Flu both in disk and arm-fractions were determined as total Flu, parent Flu (i.e. untransformed), aqueous Flu-metabolites, polar Flu-metabolites and tissue residue Flu (i.e. unextractable). Our results showed that sediment particle ingestion is a pathway by which Flu can enter benthic food webs. Flu toxicity (measured as arm-regeneration), but not net accumulation, was dependent on the nutritional quality of the ingested sediment particles. Flu bioaccumulation could not be attributed solely to equilibrium partitioning between organism lipid content and organic content of the sediment. Biotransformation of Flu by brittle stars was very limited and unaffected by organic matter quality. A. filiformis contributed to the downward transport of Flu from the surface sediment to the burrow lining. The limited breakdown of parent Flu by brittle stars and/or microorganisms was relatively higher in burrows compared to surface sediment, and highest in the presence of labile organic matter. Tissue concentrations were higher in disk than in arms, but the proportion of metabolic products relative to parent Flu was higher in arms than in the disk fraction. We estimate that the yearly mobilization of sediment-associated Flu by arm-regeneration in A. filiformis is in the range of 3.8-29.4 mug total Flu eq. m(-2) year(-1) at a sediment concentration of 30 mug Flu/g dry wt. sed. (C) 2004 Elsevier Ltd. All rights reserved.
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| 6. |
- Skjolding, L. M., et al.
(författare)
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An assessment of the importance of exposure routes to the uptake and internal localisation of fluorescent nanoparticles in zebrafish (Danio rerio), using light sheet microscopy
- 2017
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 11, s. 351-359
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Tidskriftsartikel (refereegranskat)abstract
- © 2017 Informa UK Limited, trading as Taylor & Francis Group.A major challenge in nanoecotoxicology is finding suitable methods to determine the uptake and localisation of nanoparticles on a whole-organism level. Some uptake methods have been associated with artefacts induced by sample preparation, including staining for electron microscopy. This study used light sheet microscopy (LSM) to define the uptake and localisation of fluorescently labelled nanoparticles in living organisms with minimal sample preparation. Zebrafish (Danio rerio) were exposed to fluorescent gold nanoparticles (Au NPs) and fluorescent polystyrene NPs via aqueous or dietary exposure. The in vivo uptake and localisation of NPs were investigated using LSM at different time points (1, 3 and 7 days). A time-dependent increase in fluorescence was observed in the gut after dietary exposure to both Au NPs and polystyrene NPs. No fluorescence was observed within gut epithelia regardless of the NP exposure route indicating no or limited uptake via intestinal villi. Fish exposed to polystyrene NPs through the aqueous phase emitted fluorescence signals from the gills and intestine. Fluorescence was also detected in the head region of the fish after aqueous exposure to polystyrene NPs. This was not observed for Au NPs. Aqueous exposure to Au NPs resulted in increased relative swimming distance, while no effect was observed for other exposures. This study supports that the route of exposure is essential for the uptake and subsequent localisation of nanoparticles in zebrafish. Furthermore, it demonstrates that the localisation of NPs in whole living organisms can be visualised in real-time, using LSM.
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| 7. |
- Syberg, K., et al.
(författare)
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Toward a Conceptual Approach for Assessing Risks from Chemical Mixtures and Other Stressors to Coastal Ecosystem Services
- 2017
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Ingår i: Integrated Environmental Assessment and Management. - : Wiley. - 1551-3777 .- 1551-3793. ; 13:2, s. 376-386
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Tidskriftsartikel (refereegranskat)abstract
- Growth of human populations and increased human activity, particularly in coastal areas, increase pressure on coastal ecosystems and the ecosystem services (ES) they provide. As a means toward being able to assess the impact of multiple stressors on ES, in the present study we propose an 8-step conceptual approach for assessing effects of chemical mixtures and other stressors on ES in coastal areas: step A, identify the relevant problems and policy aims; step B, identify temporal and spatial boundaries; step C, identify relevant ES; step D, identify relevant stressors (e.g., chemicals); step E, translate impacts into ES units; step F, assess cumulative risk in ES units; step G, rank stressors based on their contribution to adverse effects on ES; and step H, implement regulation and management as appropriate and necessary. Two illustrative case studies (Swedish coastal waters and a coastal lagoon in Costa Rica) are provided; one focuses on chemicals that affect human food supply and the other addresses pesticide runoff and trade-offs among ES. The 2 cases are used to highlight challenges of such risk assessments, including use of standardized versus ES-relevant test species, data completeness, and trade-offs among ES. Lessons learned from the 2 case studies are discussed in relation to environmental risk assessment and management of chemical mixtures. Integr Environ Assess Manag 2017;13:376-386. (C) 2016 SETAC
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| 8. |
- Thit, A., et al.
(författare)
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Effects of copper oxide nanoparticles and copper ions to zebrafish (Danio rerio) cells, embryos and fry
- 2017
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Ingår i: Toxicology in Vitro. - : Elsevier BV. - 0887-2333. ; 45, s. 89-100
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Tidskriftsartikel (refereegranskat)abstract
- The use of engineered metal nanoparticles (NPs) is continuously increasing and so is the need for information regarding their toxicity. This study compares the toxicity of CuO NPs with ionic Cu in three zebrafish model systems; zebrafish hepatoma cell line (ZFL), fish embryo toxicity test (FET) and fry locomotion. In the ZFL tests, no significant cytotoxicity (cell death, decreased metabolic or cell membrane integrity) was detected for either treatment, though both significantly affected reactive oxygen species (ROS) production. Embryo mortality was affected by both Cu ions and CuO NPs with similar concentration-response relationships, whereas only Cu ions affected fry mortality (24 h LC50 ≈ 30 μM, ≈ 2 mg Cu L− 1 for Cu ions and no significant mortality observed at up to 200 μM, 12.7 mg Cu L− 1 for CuO NP). Both Cu forms increased fry swimming activity during light cycles and decreased activity during dark cycles: Cu ions had significant impact at lower concentrations than CuO NPs. The implications are that Cu ions generally are more toxic than CuO NPs to embryos and fry but there is a marked difference in toxicity among the different zebrafish model systems. Metal NPs release into the environment may have adverse effects on fish and other aquatic organisms. © 2017 Elsevier Ltd
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