| 1. |
- Artigas, J., et al.
(författare)
-
Towards a renewed research agenda in ecotoxicology
- 2012
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491. ; 160, s. 201-206
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Tidskriftsartikel (refereegranskat)abstract
- New concerns about biodiversity, ecosystem services and human health triggered several new regulations increasing the need for sound ecotoxicological risk assessment. The PEER network aims to share its view on the research issues that this challenges. PEER scientists call for an improved biologically relevant exposure assessment. They promote comprehensive effect assessment at several biological levels. Biological traits should be used for Environmental risk assessment (ERA) as promising tools to better understand relationships between structure and functioning of ecosystems. The use of modern high throughput methods could also enhance the amount of data for a better risk assessment. Improved models coping with multiple stressors or biological levels are necessary to answer for a more scientifically based risk assessment. Those methods must be embedded within life cycle analysis or economical models for efficient regulations. Joint research programmes involving humanities with ecological sciences should be developed for a sound risk management. (C) 2011 Elsevier Ltd. All rights reserved.
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| 2. |
- Bach, Lis, et al.
(författare)
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Local contamination in relation to population genetic diversity and resilience of an arctic marine amphipod
- 2012
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Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X. ; 114-115, s. 58-66
-
Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to investigate whether populations inhabiting a contaminated environment are affected in terms of decreased genetic diversity due to selection of tolerant genotypes and if such effect carries a cost. Marine arctic amphipod populations (Orchomenella pinguis) were collected from sites within a contaminated fjord, as well as from sites outside the fjord on the west-coast of Greenland over three years (2006-2008). Impacts on genetic diversity, effects on resilience such as development of tolerance and cost were determined. AFLP-analysis was used to explore within and between population genetic diversity, and exposure studies were performed where the populations were subjected to known and unknown stressors to assess resilience. Populations collected at three contaminated sites all had reduced genetic diversity in 2007 compared to populations outside the fjord. This pattern was different in 2008 as all contaminated site populations increased in diversity, whereas a decrease in diversity occurred at the outer sites. However, tolerance, but even more so, cost, was related to contamination exposure in 2008, in spite of the shift in genetic diversity. We suggest that contamination rapidly induces effects that can be captured as tolerance and associated cost, whereas effects on genetic diversity can be difficult to separate from recent migration events that dilute eventual decreases in diversity due to contamination pressure. As long as impacted populations can be influenced by migration events that increase the genetic diversity and add health to an affected population, populations in contaminated areas may have enhanced probability of survival. (c) 2012 Elsevier B.V. All rights reserved.
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| 3. |
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| 4. |
- Dahllöf, Ingela, 1963, et al.
(författare)
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Long-term effects of tri-n-butyltin on the function of a marine sediment system
- 1999
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Ingår i: Marine Ecology Progress Series. ; 188, s. 1-11
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Tidskriftsartikel (refereegranskat)abstract
- The effect of tri-n-butyl-tin (TBT) was studied in a 5 mo experiment using intact coastal sediment communities in a boxcosm system. TBT-spiked sediment was added in a geometrical series between 0.0065 and 300 mu mol TBT m(-2) to a sediment that already had a background TBT concentration. Fluxes of ammonium, nitrate, phosphate, silicate and oxygen were used as effect indicators for the entire sediment system, integrating the function of all fauna and micro-organisms present. Changes in flux patterns were analysed in order to evaluate the effect of TBT on the whole sediment system using a non-parametric analysis of similarities (ANOSIM), based on Bray-Curtis similarity indices. Effects were seen at the lowest additions of 6.5 nmol TBT m(-2) as changes in flux pattern compared to the control sediments. The separate nutrient fluxes were also evaluated, showing an early response in a reduced ammonium flux and a stimulated nitrate flux for most of the TBT additions. The initial response indicated immediate effects on the microbial part of the sediment community. The fluxes changed with time in all sediment boxes, but the changes were different in sediments with added TBT compared to the control sediment. These changes showed that the heterotrophic capability to degrade organic matter and autotrophic nitrification was reduced during the 5 mo of the experiment. In the 3 highest additions, the abundance of macrofauna was reduced at the very beginning of the experiment, whereas fauna in the intermediate additions seemed to become stressed with time as indicated by an increased oxygen consumption. This study shows that minute additions of fresh TBT to an already contaminated sediment have effects on the function of the sediment system at nominal concentrations of nmol of TBT added per square metre. These additions were well below the current detection limits for TBT in sediments.
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| 5. |
- Dahllöf, Ingela, 1963, et al.
(författare)
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The Effect of TBT on the Structure of a Marine Sediment Community - a Boxcosm Study
- 2001
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Ingår i: Marine Pollution Bulletin. - 0025-326X .- 1879-3363. ; 42:8, s. 689-695
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Tidskriftsartikel (refereegranskat)abstract
- The effect of tri-n-butyl tin (TBT) on an intact marine sediment community after five months exposure was investigated. Changes in the structure of macro- and meiofauna communities were determined, as well as the functional diversity of the microbial community using BIOLOG microplates for Gram negative bacteria. Development of tolerance in the microbial community was investigated using Pollution Induced Community Tolerance (PICT) experiments with fluxes of nutrients as effect indicators. TBT affected the structure and recruitment of the macro- and meiofauna at nominal additions of 30137 mol TBT/m2 sediment. Number of species, diversity, biomass and community similarity was reduced at these concentrations compared to control. Species that molt seemed to be the most tolerant since they were predominant in boxes that had received the highest TBT addition and echinoderms were the most sensitive species. Renewed addition of TBT in PICT experiments with sediment from each boxcosm showed that TBT had an effect on individual nutrient fluxes from all sediments. Analyses of the flux patterns revealed a memory of previous TBT exposure, either due to induced tolerance or other community conditioning.
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| 6. |
- Egardt, Jenny, 1981, et al.
(författare)
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Release of PAHs and heavy metals in coastal environments linked to leisure boats
- 2018
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X. ; 127, s. 664-671
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Tidskriftsartikel (refereegranskat)abstract
- Leisure boats are responsible for elevated levels of heavy metals and PAHs in sediments in- and near marinas and natural harbours. As these compounds are released directly into the water column they also pose a threat to organisms in the pelagic environment. Passive samplers were deployed during peak and post tourist season in the water column of natural harbours, leisure boat waterways and small marinas to measure the dissolved fraction of PAHs and metal ions. Differences between seasons indicative of leisure boat activities were found as PAH composition differed between peak and post season for natural harbours and waterways, where heavier PAHs increased during peak season. During peak season, metal samplers were covered by biofouling, which likely affected the uptake. Post season metal concentrations differ between locations, with concentrations exceeding quality standards at near mainland locations where boats are maintained, compared to the sites in the archipelago. © 2017 Elsevier Ltd
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| 7. |
- Egardt, Jenny, 1981, et al.
(författare)
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Sediments indicate the continued use of banned antifouling compounds
- 2017
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 125:1-2, s. 282-288
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Tidskriftsartikel (refereegranskat)abstract
- © 2017 Elsevier Ltd. Antifouling paints are widely used to avoid organisms settling on boat hulls. The active ingredients in the paints have differed over the years where lead, TBT, irgarol and diuron have been deemed too harmful to non-target organisms and subsequently been banned within the EU. Most of these compounds however are persistent in the environment and can cause problems long after they are deposited.We have examined if present-day and banned substances used in antifouling paints can be found in sediments in a national park on the Swedish west coast. Sampled locations include waterways, natural harbours and small marinas for leisure crafts to investigate if number of visiting boats affect the concentration of antifouling compounds in sediments.Few significant differences were found when comparing the different locations types, suggesting that overall boat presence is more important than specific mooring sites, however, several banned antifouling compounds were found in the surface sediments.
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| 8. |
- Fritt-Rasmussen, J., et al.
(författare)
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Hydrocarbon and Toxic Metal Contamination from Tank Installations in a Northwest Greenlandic Village
- 2012
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Ingår i: Water Air and Soil Pollution. - : Springer Science and Business Media LLC. - 0049-6979 .- 1573-2932. ; 223:7, s. 4407-4416
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Tidskriftsartikel (refereegranskat)abstract
- Contamination from tank installations in the Arctic is an important issue, since tanks are a necessary feature of all communities, and may be a source of local pollution. Soil samples from below and around three tank installations and one reference site in the Northwest Greenlandic village of Tasiusaq were analysed for the total content of hydrocarbons (THC), lead, cadmium and organic content in the soil. Concentrations up to 77,000 mg/kg DW THC were found, mainly as weathered oil products. Elevated levels of lead and cadmium were also found in many of the samples, with concentrations up to 300 and 2 mg/kg DW, respectively. The tank installation areas were contaminated by THC, lead and cadmium compared to the reference site, and parts of the areas were highly contaminated, exceeding the Danish environmental quality criteria. The correlation between lead and cadmium concentrations was significant (p < 0.01), while no correlation existed between THC and organic matter. Small spills from daily use of the tank installations are suggested to be the source of the THC contamination, whereas the lead and cadmium contamination is suggested to originate primarily from the plume of smoke from waste incineration.
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| 9. |
- Gustafsson, Mikael, 1965, et al.
(författare)
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Benthic foraminiferal tolerance to tri-n-butyltin (TBT)
- 2000
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Ingår i: Marine Pollution Bulletin. ; 40, s. 1072-1075
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Tidskriftsartikel (refereegranskat)abstract
- Tri-n-butyltin (TBT) has been used in the marine environment as a toxic agent in antifouling paints, but unfortunately it also has negative effects on non-target organisms in the environment. In this study, intact coastal sediment was exposed for seven months to three levels of TBT corresponding to nominal additions of 0.00, 0.02 and 2.00 nmol TBT per g dry sediment. This paper presents the first attempt to find out how living benthic foraminifera respond to TBT, Increased foraminiferal abundance in the 0.02 nmol mesocosm could be an effect of decreased predation (competition), since other representatives of meiofauna and macrofauna tended to be less tolerant to TBT, Increasing toxicity in the most contaminated mesocosm group (2.00 nmol) resulted in a less abundant foraminiferal population suggesting that TBT affects the foraminiferal community.
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| 10. |
- Hassellöv, Ida-Maja, 1974, et al.
(författare)
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Verification of a benthic boxcosm system with potential for extrapolating experimental results to the field
- 2007
-
Ingår i: Journal of Experimental Marine Biology and Ecology. - : Elsevier BV. - 0022-0981. ; 353:2, s. 265-278
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Tidskriftsartikel (refereegranskat)abstract
- A marine mesocosm system (boxcosm system) was developed for ecological and/or ecotoxicological studies of sediment community function and structure. The system consists of continuous flow-through incubations of intact sediment samples, each with a surface area of 0.25 m2. The experimental setup enables repeated non-destructive measurements of benthic fluxes, such as of nutrients, oxygen and dissolved inorganic carbon, over the sediment–water interface. The benthic fluxes reflect the function of the sediment community, integrating over the chemical, biological and physical activities in the sediment. The suitability of the boxcosm system for controlled, highly ecologically relevant studies of intact sediment communities was evaluated in two experiments of six weeks and five months duration respectively, where the functional and structural development over time was compared to the development of the sampling site. The function of the sediment was measured as nutrient and oxygen fluxes, and the structural component consisted of microbial functional diversity and meio- and macrofauna composition. Differences between the boxcosm and the sampling site were detected especially in nitrate fluxes and meiofauna diversity and abundance, but all differences fell within seasonal and inter-annual variability at the sampling site. The cause of the differences could be referred to differences in oxygen availability, supply of organic matter particles, and recruitment of larvae. These factors can however be compensated for within the present setup. The study shows that the boxcosms are suitable tools for ecologically relevant studies generating comparable conditions to the natural environment.
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| 11. |
- Jönander, Christina, 1990, et al.
(författare)
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Exposure to closed-loop scrubber washwater alters biodiversity, reproduction, and grazing of marine zooplankton
- 2023
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Ingår i: Frontiers in Marine Science. - 2296-7745. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Shipping is a large industry responsible for atmospheric emissions of hazardous substances including SOX, NOX, and particulate matter. Many ships have installed exhaust gas cleaning systems (scrubbers) to remove primarily SOX from the exhaust, but the hazardous substances are instead transferred to the water used in the scrubbing process. Ships with closed-loop scrubbers recirculate the water but can still discharge around 126-150 m3 directly to the surrounding marine environment every day. The discharged water contains metals and organic substances, such as polycyclic aromatic hydrocarbons, that are known to be toxic to marine zooplankton. Here we show that closed-loop scrubber washwater is toxic to communities of marine mesozooplankton at our lowest tested dilution, 1.5% (v/v), and affects survival, reproduction, diversity, and ability to predate on microzooplankton. The cumulative toxic unit of the undiluted closed-loop scrubber washwater was estimated to 17, which indicates that the water could be toxic at levels below what was tested in this study. Among all detected substances, vanadium, copper, benzo[ghi]perylene, nickel, and zinc were identified as toxicity-driving substances in the order listed. Closed-loop scrubber washwater has been shown to affect development and survival in single species of copepods, but here we find evidence of toxicity at the community level, irrespective of seasonal community structure, and that the exposure has potential to disrupt the interactions between trophic levels in the pelagic food web. We show that the closed-loop scrubber washwater cause both lethal and sublethal effects in marine zooplankton, due to contaminants, some of which are persistent in the marine environment.
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| 12. |
- Jönander, Christina, 1990, et al.
(författare)
-
Short and long-term effects of low-sulphur fuels on marine zooplankton communities.
- 2020
-
Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X. ; 227
-
Tidskriftsartikel (refereegranskat)abstract
- International shipping is responsible for the release of numerous contaminants to the air and the marine environment. In order to reduce airborne emissions, a global 0.5 % sulphur limit for marine fuels was implemented in January 2020. Recently, a new generation of so-called hybrid fuels that meet these new requirements have appeared on the market. Studies have shown that these fuels have physical properties that make conventional clean-up methods difficult, but few have studied their effects on marine life. We conducted short and long-term microcosm experiments with natural mesozooplankton communities exposed to the water accommodated fractions (WAFs) of the hybrid fuel RMD80 (0.1 % sulphur) and a Marine Gas Oil (MGO). We compared the toxicity of both fuel types in 48h short-term exposures, and studied the effects of the hybrid fuel on community structure over two generations in a 28-day experiment. The F0 generation was exposed for eight days and the F1 generation was raised for 22 days without exposure. GC-MS and GC-FID analysis of the WAFs revealed that the hybrid fuel was dominated by a mixture of volatile organic compounds (VOCs) and poly aromatic hydrocarbons (PAHs), whereas the MGO was mainly composed of VOCs. We observed significant short-term effects on copepod egg production from exposure to 25 % hybrid fuel WAF, but no effects from the MGO WAF at equivalent WAF dilution. In the long-term experiment with RMD80, the feeding rate was initially increased after exposure to 0.5-1.1 % hybrid fuel WAF, but this did not increase the copepod egg production. Significant change in community structure was observed after eight days in the F0 community at 0.5-3.3 % WAF. Indications of further alterations in species abundances was observed in the F1 community. Our results demonstrate that the MGO is a less toxic low-sulphur alternative to the hybrid fuel for marine zooplankton, and that a hybrid fuel spill could result in altered diversity of future generations of copepod communities.
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| 13. |
- Jönander, Christina, 1990, et al.
(författare)
-
Single substance and mixture toxicity of dibutyl-phthalate and sodium dodecyl sulphate to marine zooplankton
- 2022
-
Ingår i: Ecotoxicology and Environmental Safety. - : Elsevier BV. - 0147-6513 .- 1090-2414. ; 234
-
Tidskriftsartikel (refereegranskat)abstract
- Several contaminants exceed their environmental thresholds in Swedish marine surface waters. We ranked the toxicity-drivers among contaminants detected near heavy industry, based on toxicity to zooplankton, and identified di-butyl phthalate and sodium dodecyl sulphate as contaminants of concern. We tested their acute individual and mixture toxicity by assessing effects on mortality, biodiversity, algal growth, and copepod reproduction in natural mesozooplankton communities. The mixture effects were compared to Independent Action mixture model predictions. Egg production and algae growth were affected at 4 µmol/l DBP, and effects on mortality, algae growth and biodiversity were observed at 12 µmol/l SDS. The mixture (1 µmol/l DBP, 3 µmol/l SDS) affected all endpoints, and the observed effects were underestimated by 21% on average compared to predictions. We found that the successional trajectory in zooplankton communities was compound dependant, and that DBP and SDS are toxic to marine zooplankton, but at levels above measured environmental concentrations.
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| 14. |
- Klok, C., et al.
(författare)
-
Qualitative use of Dynamic Energy Budget theory in ecotoxicology Case study on oil contamination and Arctic copepods
- 2012
-
Ingår i: Journal of Sea Research. - : Elsevier BV. - 1385-1101. ; 73, s. 24-31
-
Tidskriftsartikel (refereegranskat)abstract
- The Dynamic Energy Budget (DEB) theory provides a logic and consistent framework to evaluate ecotoxicological test results. Currently this framework is not regularly applied in ecotoxicology given perceived complexity and data needs. However, even in the case of low data availability the DEB theory is already useful. In this paper we apply the DEB theory to evaluate the results in three previously published papers on the effects of PAHs on Arctic copepods. Since these results do not allow for a quantitative application we used DEB qualitatively. The ecotoxicological results were thereby set in a wider ecological context and we found a logical explanation for an unexpected decline in hatching success described in one of these papers. Moreover, the DEB evaluation helped to derive relevant ecological questions that can guide future experimental work on this subject. (c) 2012 Elsevier B.V. All rights reserved.
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| 15. |
- Landquist, Hanna, 1984, et al.
(författare)
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A fault tree model to assess probability of contaminant discharge from shipwrecks
- 2014
-
Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 88:1-2, s. 239-248
-
Tidskriftsartikel (refereegranskat)abstract
- Shipwrecks on the sea floor around the world may contain hazardous substances that can cause harm to the marine environment. Today there are no comprehensive methods for environmental risk assessment of shipwrecks, and thus there is poor support for decision-making on prioritization of mitigation measures. The purpose of this study was to develop a tool for quantitative risk estimation of potentially polluting shipwrecks, and in particular an estimation of the annual probability of hazardous substance discharge. The assessment of the probability of discharge is performed using fault tree analysis, facilitating quantification of the probability with respect to a set of identified hazardous events. This approach enables a structured assessment providing transparent uncertainty and sensitivity analyses. The model facilitates quantification of risk, quantification of the uncertainties in the risk calculation and identification of parameters to be investigated further in order to obtain a more reliable risk calculation.
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| 16. |
- Landquist, Hanna, 1984, et al.
(författare)
-
Evaluating the needs of risk assessment methods of potentially polluting shipwrecks
- 2013
-
Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 119, s. 85-92
-
Tidskriftsartikel (refereegranskat)abstract
- Shipwrecks deteriorate and the probability of a release of oil increases with time on the sea floor. The potential leakage is a risk to the marine environment and may also have social and economic consequences. The purpose of this study was to evaluate existing methods for risk assessment of shipwrecks and suggest a generic risk assessment framework. A risk assessment is necessary for providing decision support on remediation actions and thus enabling an efficient use of available resources. Existing risk assessment methods aimed for assessing shipwrecks were evaluated by comparison to relevant parts of an international standard on risk management. The comparison showed that existing methods lack several key components of risk assessment procedures. None of the evaluated methods provide a comprehensive risk assessment for potentially polluting shipwrecks and few take into account uncertainty and sensitivity. Furthermore, there is a need to develop risk assessment methods considering long-term effects of continuous release of oil into the marine environment. Finally, a generic comprehensive framework for risk assessment of shipwrecks is suggested.
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| 17. |
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| 18. |
- Larsen, M. M., et al.
(författare)
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Lead isotopes in marine surface sediments reveal historical use of leaded fuel
- 2012
-
Ingår i: Journal of Environmental Monitoring. - 1464-0325 .- 1464-0333. ; 14:11, s. 2893-2901
-
Tidskriftsartikel (refereegranskat)abstract
- Analyses of lead (Pb) isotopes have been performed in terrestrial and fresh water environments to estimate historical uses of leaded fuel, but so far this method has not been employed in studies of worldwide marine surface sediments. We analyzed Pb and its isotopes in 23 surface sediments from four continents collected during the Galathea 3 expedition in 2006-2007. To enhance the anthropogenic signal, a partial digestion using nitric acid was performed. The concentrations of Pb, Th, U and Al were determined with an ICP-Quadrupole MS, and Pb-isotope ratios with an ICP-multi-collector MS. The samples could be divided into three groups: Harbor areas in larger cities with concentrations of 150 to 265 mg kg(-1) dry weight, smaller towns with concentrations between 20 and 40 mg kg(-1) dry weight, and remotely located sites with concentrations below 15 mg kg(-1) dry weight. Pb-isotope ratios were compared to literature values for gasoline and local or geological background values, and the contribution of leaded-gasoline to total concentrations was calculated for contaminated sites using both a one-dimensional and a novel two-dimensional (vector) method. The North American sites had Pb-isotope ratios corresponding to the US leaded gasoline, with 24-88% of the Pb from leaded gasoline. Samples from Oceania showed Pb-isotope ratios corresponding to Australian gasoline, with 60% attributed to leaded gasoline in Sydney and 21% in Christchurch. Outside Cape Town, 15 to 46% of Pb in sediments was from leaded gasoline.
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| 19. |
- Lindgren, Fredrik, 1979, et al.
(författare)
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Analyzing changes in sediment meiofauna communities using the image analysis software ZooImage
- 2013
-
Ingår i: Journal of Experimental Marine Biology and Ecology. - : Elsevier BV. - 0022-0981. ; 440, s. 74-80
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Tidskriftsartikel (refereegranskat)abstract
- Wehere propose a novelmethod of automatic classification of higher taxa frombenthicmeiofaunal communities using the image analysis software ZooImage. Meiofauna was extracted from sediment at five sites at different depths in the Gullmar Fjord on the Swedish west-coast, and digitalized through scanning. The resulting images were analyzed with the image analysis software, by comparing them to a reference image library of meiofaunal groups of higher taxa, as well as non-faunal groups consisting of different types of debris. The accuracy of the analyses was tested using ZooImage internal cross-validation method, and by comparing digitalized samples from the different sites with manually classified samples. The internal validation accuracy (82–93%)was comparable to prior published studies on zooplankton. The largest errors in classification were within the non-faunal groups and accuracy for classification of faunal groups was as high as 93%. Misclassification within the faunal groups was mainly due to either too few images of some classes in the training set, or to when fauna could not be sufficiently separated from debris in the images used for the library, causing interference in the learning algorithm. Comparison with manual classification confirmed the errors revealed in the internal cross-validation. Statistical analysis revealed differences in the meiofauna communities between different depths as well as a temporal change
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| 20. |
- Lindgren, Fredrik, 1979, et al.
(författare)
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Induced tolerance in situ to chronically PAH exposed ammonium oxidizers
- 2017
-
Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 120:1-2, s. 333-339
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Tidskriftsartikel (refereegranskat)abstract
- Sediment was sampled in the vicinity of a long-term source of Polycyclic Aromatic Hydrocarbons (PAHs) to evaluate whether tolerance can be induced in situ. Total PAH concentrations as well as the bioavailable PAHs were measured, and for nine PAHs the pore water concentration could be calculated. An induced tolerance in the ammonium oxidizing community was detected at the site with highest PAH concentration and tolerance was strongest, although not significantly, correlated to bioavailable alkylated PAHs. In addition, the tolerant microbial community showed a significant lower baseline capability for nitrification with an on average 35% reduction compared to the other sites. Meiofaunal community structure differed between all sites, and the difference was significantly correlated to bioavailable alkylated PAHs and PAH31 concentrations. The results suggest that in order to judge magnitude of long-term effects, the bioavailable fraction is to be preferred, and when possible as estimation of the freely dissolved concentration.
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| 21. |
- Lindgren, Fredrik, 1979, et al.
(författare)
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Low concentrations of PAHs induce tolerance in nitrifying bacteria
- 2015
-
Ingår i: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745. ; 2:35, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- The ability of marine microbes to develop tolerance to polycyclic aromatic hydrocarbons (PAHs) was examined in a 90-day experiment. PAH levels in sediment were increased 0.3 and 1.6 times compared to the control sediment. Day 30, 60, and 90 the microbes were re-exposed to PAHs in a short-term toxicity test to detect tolerance, where nitrification and denitrification were used as endpoints. In addition, molecular analysis of the microbial communities was performed to detect possible differences in proportions of nitrifying bacteria compared to total bacterial abundance (amoA/rpoB-ratio) between treatments and control. We here show PAH-induced tolerance in nitrifying microbial communities after 60 and 90 days of pre-exposure, as potential nitrification EC10-values were significantly higher in the low treatment (L) after 60 days and in both treatments after 90 days compared to control. Tolerance development in denitrification was not detected. Furthermore, the developed tolerance resulted in reduced nitrification efficiency, compared to control. It was also shown that the induced tolerance produced dissimilar amoA/rpoB-ratio between treatments and control, indicating that development of tolerance changed the community composition and that the development time depended on initial exposure. The results from this study have implications for future studies or environmental monitoring programs of long-term oil and PAH-contaminated sites. The possibility for development of tolerance needs to be taken into account and potential nitrification can be used for evaluation of marine microbial health. Furthermore, changed proportions of nitrifying microbes can alter the capacity of ammonium oxidizing in benthic marine sediments.
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| 22. |
- Lindgren, Fredrik, 1979, et al.
(författare)
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Meiofaunal and bacterial community response to diesel additions in a microcosm study
- 2012
-
Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 64:3, s. 595-601
-
Tidskriftsartikel (refereegranskat)abstract
- Effects of low PAH-containing diesel were studied in a 60-day microcosm experiment at PAH concentrations 130, 1300 and 13,000 lg/kg sediment. Nutrient fluxes, potential nitrification and meiofaunal community composition were analysed at three time points. Changed PNOx-fluxes indicated reduced sediment nitrification in Medium and High with time, in agreement with lowered potential nitrification rates in all treatments. Reduction in silicate and phosphate fluxes over time suggested severe effects on activity of meiofauna. Reduced activity increased the anoxic sediment layer, which could have contributed to the changed PNOx-fluxes. There were significant differences in meiofaunal community composition after 30 and 60 days in Medium and High. Changes were due to increasing numbers of harpacticoids and the foraminiferan group Rotaliina, as well as decreasing numbers of Nematodes and the foraminiferan group Reophax. In spite of the low PAH-level, small additions of this diesel can still have pronounced effects on meiofaunal and bacterial communities.
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| 23. |
- Lindgren, Fredrik, 1979, et al.
(författare)
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PAH effects on meio- and microbial benthic communities strongly depend on bioavailability
- 2014
-
Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X .- 1879-1514. ; 146, s. 230-238
-
Tidskriftsartikel (refereegranskat)abstract
- The effects of anthropogenic pollutants in dissimilar habitats can vary depending on differences in bioavailability. The factors determining bioavailability are not yet fully understood. This study was performed to evaluate whether analysis of total PAH concentrations in sediments is a satisfactory measurement to indicate environmental effects or if bioavailability is needed to be taken into account. We have here performed a 60-day experiment, where nominal PAH concentrations of 1300. μg/kg sediment were added to three different marine sediments. Meiofaunal and microbial communities were analyzed for alterations in community response at 30 and 60 days.Results showed that bioavailability of PAHs varied between the three different sediments. Nonetheless, the petroleum addition gave rise to significant negative effects on all three sediments at both time points. The two direct measurements of toxicity on the microbial community, potential nitrification and denitrification, displayed a lower effect of the PAH addition in the muddy sediment at both time points, compared to the other two sediment types. No effects were seen in the analysis of meiofaunal community structure. Measurements of PAH bioavailability in the three sediment types concurred with the results from the microbial community, revealing a lower bioavailability in the muddy sediment compared to the other two sediment types, 34% compared to sandy and 18% compared to organic at day 0. At day 60 it was 61% lower compared to sandy and 20% lower compared to organic. The negative effects of the PAH addition on the microbial nitrogen cycle were in six out of eight cases best correlated to the amount of alkylated bioavailable PAH in the sediments, and thus microbial nitrogen cycle is a possible good indicator for assessing PAH-induced stress.The results presented here have implications for risk analysis studies of petroleum-contaminated marine sediments; consequently, sediment characteristics and its effects on bioavailability are important to include. In addition, these results add to the understanding that bioavailability measurements of PAHs are a more correct assessment compared to measurements of total PAH concentrations, and need to be included when estimating effects of PAHs in marine benthic communities. © 2013 Elsevier B.V.
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| 24. |
- Long, M., et al.
(författare)
-
Endocrine-Disrupting Effects of Compounds in Danish Streams
- 2014
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Ingår i: Archives of Environmental Contamination and Toxicology. - : Springer Science and Business Media LLC. - 0090-4341 .- 1432-0703. ; 66:1, s. 1-18
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Tidskriftsartikel (refereegranskat)abstract
- Effluents from municipal wastewater-treatment plants and scattered dwellings, as well as runoff from agricultural fields, are sources of endocrine-disrupting compounds (EDCs) in the aquatic environment. The present study investigated the correlation between the occurrence of EDCs in nine Danish streams using passive samplers (polar organic integrative samplers and silicone membranes) and determined their possible biological effects as assessed by mammal cell cultures and the mussel (Unio tumidus). The passive samplers and mussels were exposed simultaneously at the study sites. The extracts from the passive samplers were used to measure the concentrations of EDCs and the biological effects on the estrogen (ER), androgen (AR), and aryl hydrocarbon (AhR)-receptor transactivation. Male mussels were investigated for biomarkers of endocrine effects, such as the levels of vitellogenin-like proteins measured as alkali-labile phosphate (ALP). EDC concentrations, hormone-receptor transactivation (ER, AR, AhR), and level of ALP were greater downstream of wastewater-treatment plants compared with upstream sites and sites supposed to be relatively nonimpacted by wastewater. Furthermore, there was a significant positive correlation between in vitro AhR transactivation and frequency of ALP of male mussels. We conclude that wastewater effluent is an important source of endocrine-disrupting effects in the aquatic environment and that the combination of biological effect measurements and chemical analyses based on passive sampling is useful in the assessment of the ecological state of the aquatic environment.
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| 25. |
- Lund-Hansen, Lars Chresten, et al.
(författare)
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A fjord with a land-terminating glacier: Meltwater, bio-optics, particulate matter, nutrients, phytoplankton species, and primary production in west Greenland
- 2023
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Ingår i: Regional Studies in Marine Science. - 2352-4855. ; 64
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Tidskriftsartikel (refereegranskat)abstract
- Land-terminating glaciers and submarine melting of marine-terminating glaciers are significant features in Arctic regions and are foreseen to become more frequent as marine-terminating glaciers ultimately develop into a land-terminated state. A transition driven by the continuous rise in Arctic air temperatures, and emphasizes the importance of studies of land-terminating glaciers their bio-optical properties and biogeochemistry. Kangerlussuaq in west Greenland with a land-terminating glaciers and was selected for this study. During a research cruise we measured spectral and PAR attenuation, particulate matter concentrations, salinity, nutrient concentrations, Chla, and phytoplankton species composition, along a transect from river outlet to open marine waters. Results showed that surface waters in Kangerlussuaq were strongly influenced by meltwater with low salinities, high particulate matter concentrations, high PAR and spectral light attenuation coefficients, and low nutrient concentrations. Spectral composition was also affected by the particulate matter. PAR photic depths varied between 4 and 9 m dependent on particulate matter concentrations. There was a decrease with distance from outlet in silicate concentrations, and opposite for phosphate, which increased significantly from river outlet to the marine. Phytoplankton species number (42) and diversity were high at the marine station but low (3) in turbid waters dominated by the diatom Skeletonema costatum in high numbers. A meltwater plume covered about 50 % of the Kangerlussuaq at average discharges in early August. Primary production was quantified with a simple model based on light attenuation coefficients, and showed a near exponential decrease in production with increase in attenuation.
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| 26. |
- Lund-Hansen, L. C., et al.
(författare)
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Summer meltwater and spring sea ice primary production, light climate and nutrients in an Arctic estuary, Kangedussuaq, west Greenland
- 2018
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Ingår i: Arctic Antarctic and Alpine Research. - : Informa UK Limited. - 1523-0430 .- 1938-4246. ; 50:1
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Tidskriftsartikel (refereegranskat)abstract
- The estuary is dominated by sea ice and snow cover from winter to spring, and a highly turbid meltwater plume during summer. The aims were to quantify the variability in optical conditions, inorganic nutrients, and primary production between these two extremes, and identify the drivers of variability. Data were obtained during a summer cruise along a transect in the estuary in August 2007, and a spring campaign on the ice in March 2011. The study comprises conductivity, temperature, and depth (CTD), K-d (PAR), K-d (A), PAR transmittance, photic depth, chl-a, nutrients (NO3, NO2, NH3 , PO4, and SiO2), primary production, and sediment concentrations. PAR transmittance varied between 5% below snow and ice and 85% in clear water with 44% in turbid meltwater. Primary production rates were similar below the ice in March (76.8 mg C m(-2) d(-1)) and in the highly turbid meltwater in August (94.8 mg C m(-2) d(-1)), but higher (246.6 mg C m(-2) d(-1)) at the mouth of the fjord. Meltwater inflow was the main driver of variability during summer and the snow and sea ice during spring. Under-ice primary production will increase three-fold with less snow on the sea ice, and the higher meltwater turbidity with increased melting of glacial ice and runoff will only reduce primary production slightly.
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