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Despite the importance of the cold-water coral Lophelia pertusa to deep-sea reef ecosystem functioning, current knowledge of key physiological responses to available food resources is scarce. Scenarios with varying food density may help to understand how corals deal with seasonal variations in the dark ocean and might be used to study consequences of anthropogenic activities potentially affecting food availability. Thus, the physiological responses of L. pertusa to varying food (Artemia salina nauplii) concentration, ranging from 20% to 300% of carbon equivalent turned over by basal coral respiration, were investigated. A starvation group was also included. Measurements of respiration, growth, mucus production, and energy reserves (storage fatty acids) were performed at several time intervals over 26 weeks. In general, data showed a stronger effect of experimental time on measured responses, but no significant influence of food density treatment. In starved corals, respiration rate declined to 52% of initial respiration, while skeleton growth rate was maintained at the same rate as Artemia-fed corals throughout the investigation. Mucus production measured as the sum of dissolved organic carbon (DOC) and particulate organic carbon (POC) was also similar across food treatments, but POC production exceeded that of DOC at the highest food density. No marked effect was observed on storage fatty acids. These results confirm that L. pertusa is highly resilient to environmental conditions with suboptimal food densities over a time scale of months. Regulation of several physiological processes, including respiration and mucus production, possibly in combination with an opportunistic feeding strategy, contributed to this tolerance to maintain viable corals. Thus, it appears that L. pertusa is well adapted to life in the deep sea.

Today's benthic offshore biological monitoring of oil & gas (O&G) activities relies on macrofauna taxa enumeration. For the future, analysis of DNA isolated directly from sediments holds great potential for multi-trophic biodiversity surveys and the monitoring of a larger spectrum of benthic taxa, including micro-fauna. Here, we evaluate more specifically the potential of microfauna-specific gene quantification in relation to both petroleum-related discharge compounds and other seafloor environmental properties. We carried out this evaluation using sediment samples collected at drilling Region III on the Norwegian continental shelf where DNA metabarcoding of eukaryotic diversity was already performed. Generally, the quantification of microfauna indicator taxa related well to the gradient of contamination on the seafloor. Contrary to eukaryotic Euplotida, metabarcoding data and qPCR numbers for indicative prokaryotic taxa showed the same relationship to offshore contaminants (both showed positive relationship). We found absolute numbers of SSU rRNA gene copies of (1) Dinophyceae, Bacillariophyceae and Alcanivorax were correlated with the level of petroleum-related compounds but not with other environmental variables, (2) bacteria closely related to Shewanella were correlated with the concentration of Ba, PAH, as well to percent of gravel, (3) Desulfobacteriales correlated with petroleum-related contaminants, but as well with percent of gravel and grain size. Findings from our study suggest that biomonitoring surveys of O&G activities on benthos could benefit from quantification of specific micro-fauna indicators that is simpler and faster than the methods currently used for impact assessment of benthos.

Mussels (Mytilus edulis) were continuously exposed to dispersed crude oil (0.015-0.25mg/l) for 7 months covering the whole gamete development cycle. After 1 month exposure to 0.25 mg oil/l, the level of alkali-labile phosphates (ALP) and the volume density of atretic oocytes in female gonads were higher than those in the gonads of control females, indicating that oil affected the level of vitellogenin-like proteins and gamete development. Spawning of mussels was induced after 7 months oil exposure. Parental oil exposure did not affect subsequent fertilization success in clean seawater but this was reduced in 0.25 mg oil/l. Parental exposure to 0.25 mg oil/l caused both slow development and a higher percentage of abnormalities in D-shell larvae 2 days post-fertilization; reduced growth 7 days post-fertilization. These effects were greatly enhanced when larval stages were maintained at 0.25 mg oil/l. Similar studies are warranted for risk assessment prognosis.

Ocean acidification (OA) resulting from anthropogenic emissions of carbon dioxide (CO(2)) has already lowered and is predicted to further lower surface ocean pH. There is a particular need to study effects of OA on organisms living in cold-water environments due to the higher solubility of CO(2) at lower temperatures. Mussel larvae (Mytilus edulis) and shrimp larvae (Pandalus borealis) were kept under an ocean acidification scenario predicted for the year 2100 (pH 7.6) and compared against identical batches of organisms held under the current oceanic pH of 8.1, which acted as a control. The temperature was held at a constant 10°C in the mussel experiment and at 5°C in the shrimp experiment. There was no marked effect on fertilization success, development time, or abnormality to the D-shell stage, or on feeding of mussel larvae in the low-pH (pH 7.6) treatment. Mytilus edulis larvae were still able to develop a shell in seawater undersaturated with respect to aragonite (a mineral form of CaCO(3)), but the size of low-pH larvae was significantly smaller than in the control. After 2 mo of exposure the mussels were 28% smaller in the pH 7.6 treatment than in the control. The experiment with Pandalus borealis larvae ran from 1 through 35 days post hatch. Survival of shrimp larvae was not reduced after 5 wk of exposure to pH 7.6, but a significant delay in zoeal progression (development time) was observed.

Polar marine surface waters are characterized by high levels of dissolved oxygen, seasonally intense UV irradiance and high levels of dissolved organic carbon. Therefore, the Arctic sea-ice habitat is regarded as a strongly pro-oxidant environment, even though its significant ice cover protects the ice-associated ( = sympagic ) fauna from direct irradiation to a large extent. In order to investigate the level of resistance to oxyradical stress, we sampled the sympagic amphipod species Gammarus wilkitzkii during both winter and summer conditions, as well as exposed specimens to simulated levels of near-natural and elevated levels of UV irradiation. Results showed that this amphipod species possessed a much stronger antioxidant capacity during summer than during winter. Also, the experimental UV exposure showed a depletion in antioxidant defences, indicating a negative effect of UV exposure on the total oxyradical scavenging capacity. Another sympagic organism, Onisimus nanseni , was sampled during summer conditions. When compared to G. wilkitzkii , the species showed even higher antioxidant scavenging capacity.

The scientific goal of the present work is the development of a new molecular biomarker as a biomonitoring tool for early assessment of the biological effect of complex mixtures of pollutants (especially polycyclic aromatic hydrocarbons) and validation of the approach by comparison with standard methodologies. Hence, a DNA‐based biosensor, which is able to detect the presence of compounds with affinity for DNA to measure their effect on the guanine base, was used in this research.

Despite the extensive transport of chemicals at sea, there is current lack of knowledge of the fate and effects of many of them on the marine biota. The current regulation that follows the GESAMP-MARPOL classification is mainly based on ecotoxicity assessment from fresh water based studies. Repetitive spills in marine coastal environment from tanker ship loaded with several thousand tonnes of chemicals raised concern about whether the existing freshwater data location can be used to predict the behaviour and the environmental effects of contaminants in marine surroundings. There is a general lack of information of the fate of chemicals at sea. A deviating pattern in marine environment from that in freshwater may have significant consequences for the counteracting actions taken to fight the spill, on staff working on the site of spill as well as on marine life present in the vicinity of the accident. In the present article, an environmental effect study of styrene was conducted as part of the ECOPEL program. We report some biological effects of styrene in laboratory-exposed marine organisms. Styrene was continuously supplied at a nominal concentration of 2mg L(-1) over 7 days to both mussels (Mytilus edulis) and fish (Symphodus mellops). At the end of this period, DNA damage was assessed by the Comet assay performed on blood (fish) and haemolymph (mussel) cells. In mussels, the lysosomal membrane stability was additionally assessed by the neutral red retention time assay (NRRT). Significant biological responses were observed over the studied period in both organisms with these two tests. Hence, the results favour the use of a biomarker-based approach to assess the health conditions in case of spill.

Blood plasma and serum are very useful samples for the detection, identification and quantitation of proteins associated with both health and disease. However, analysis of plasma and serum is a challenge because traces of interesting polypeptides and proteins can be dominated by the very high concentration of albumin present. Albumin may be depleted by adsorption to immunoaffinity columns or to columns containing dyes such as Cibacron Blue, or by ultrafiltration, but these methods are far from ideal. We describe a new peptide-based affinity medium which is effective for removing albumin and is very specific. The albumin-binding capacity is at least 14 mg per mL of gel. The material may be reused hundreds of times after a simple regeneration step involving NaOH, with full retention of specificity and capacity. The material was tested with human and monkey plasma and serum and rat serum, and has been used to deplete litre volumes of human plasma. The development of other peptide-based affinity media to deplete abundant proteins is briefly discussed.

The single-cell microgel electrophoresis assay or the comet assay was used to evaluate DNA damage of dispersed crude oil on sea urchins (Strongylocentrotus droebachiensis) and mussels (Mytilus edulis L.). Sea urchins were exposed to 0.06 and 0.25 mg/L dispersed crude oil in a continuous flow system, while the mussels were exposed to 0.015, 0.06 and 0.25 mg/L dispersed crude oil. Sea urchin coelomocytes and mussel haemocytes were sampled after 4 and 5 weeks exposure, respectively. In the sea urchin coelomocytes, there was a significant concentration-related increase in the percentage of DNA in comet tail. In mussel haemocytes, there was a significantly higher percentage of DNA in comet tail for all treatments compared to the control. The responses were concentration-related up to 0.06 mg/L oil. The two highest exposure concentrations of mussels were not significantly different from each other. These results indicate that the comet assay can be used for biomonitoring of DNA damage in marine invertebrates following oil contamination.

Human blood plasma is a useful source of proteins associated with both health and disease. Analysis of human blood plasma is a challenge due to the large number of peptides and proteins present and the very wide range of concentrations. In order to identify as many proteins as possible for subsequent comparative studies, we developed an industrial-scale (2.5 liter) approach involving sample pooling for the analysis of smaller proteins (M(r) generally < ca. 40 000 and some fragments of very large proteins). Plasma from healthy males was depleted of abundant proteins (albumin and IgG), then smaller proteins and polypeptides were separated into 12 960 fractions by chromatographic techniques. Analysis of proteins and polypeptides was performed by mass spectrometry prior to and after enzymatic digestion. Thousands of peptide identifications were made, permitting the identification of 502 different proteins and polypeptides from a single pool, 405 of which are listed here. The numbers refer to chromatographically separable polypeptide entities present prior to digestion. Combining results from studies with other plasma pools we have identified over 700 different proteins and polypeptides in plasma. Relatively low abundance proteins such as leptin and ghrelin and peptides such as bradykinin, all invisible to two-dimensional gel technology, were clearly identified. Proteins of interest were synthesized by chemical methods for bioassays. We believe that this is the first time that the small proteins in human blood plasma have been separated and analyzed so extensively.

Within the frame of a large environmental study, we report on a research program that investigated the potential for bioaccumulation and subsequent effect responses in several marine organisms exposed to chronic levels of dispersed crude oil. Body burden can be estimated from kinetic parameters (rate constants for uptake and elimination), and appropriate body burden-effect relationships may improve assessments of environmental risks or the potential for such outcomes following chronic discharges at sea. We conducted a series of experiments in a flow-through system to describe the bioaccumulation kinetics of polycyclic aromatic hydrocarbons (PAH) at low concentrations of dispersed crude oils. Mussels (Mytilus edulis) and juvenile turbot (Scophthalmus maximus) were exposed for periods ranging from 8 to 21 d. Postexposure, the organisms were kept for a period of 9 to 10 d in running seawater to study elimination processes. Rate constants of uptake (k1) and elimination (k2) of the PAHs during and following exposure were calculated using a first-order kinetic model that assumed a decrease of the substances in the environment over time. The estimated bioconcentration factor was calculated from the ratio of k1/k2. The kinetic parameters of two-, three-, and four-ring PAHs in mussel and fish are compared with estimates based on hydrophobicity alone, expressed by the octanol-water partition coefficient, Kow (partitioning theory). A combination of reduced bioavailability of PAHs from oil droplets and degradation processes of PAHs in body tissues seems to explain discrepancies between kinetic rates based on Kow and actual kinetic rates measured in fish. Mussels showed a pattern more in compliance with the partitioning theory.

The fate of hydrocarbons discharged at sea was studied in laboratory exposures examining the uptake of PAC (polyaromatic compounds) in marine organisms. Methodology and species selection were guided by the Northwest European (OSPAR) convention. The acute toxicity of poorly soluble substances is normally assessed by preparing water accommodated fractions (WAF). Following such tests we studied PAC uptake in unicellular algae, crustaceans and fish. Preparation of WAF was first improved because in the standard procedure, oil droplet size increased with oil loading and flask size. At similar exposure levels the proportion of large molecular weight PAC associated with algae increased when the density of algae decreased. However, as body size increased via crustaceans to fish more of the smaller molecular weight PAC were bioconqentrated. Organism density and type of organism thus influence the abundance of PAC in food chains.

Assessing the fate in marine biota of hydrocarbons derived from oil particles that are discharged during exploration and production is of relevant environmental concern. However, a rather complex experimental setup is required to carry out such investigations. In this study, a sophisticated tool, the continuous-flow system (CFS), was used to mimic dispersed oil exposure to marine biota. Polycyclic aromatic hydrocarbon (PAH) uptake was studied in two species, the blue mussel Mytilus edulis and juvenile of the turbot Scophthalmus maximus, and in semipermeable membrane devices (SPMD) exposed to crude oil dispersed in a flow-through system. After an exposure period of 8 to 21 d, elimination in organisms and devices was analyzed for 9 to 10 d following transfer to PAH-free seawater. Principal component analysis (PCA) revealed different PAH patterns. In mussel and SPMD, the PAH profiles were very close to that analyzed in seawater. Slight differences were, however, indicated for large molecules with log Kow above six. Nonachievement of steady-state concentration and bioavailability of PAH in oil droplets may account for these differences. The PAH composition in fish revealed only congeners with two to three aromatic rings. A combination of bioavailability and efficient metabolism of the larger PAH molecules may explain this pattern. The CFS made possible a better understanding of some critical factors governing bioconcentration in marine biota from dispersed oil. Yet the results illustrate that uptake of PAH from exposure to oil particles is complex and that different species may bioconcentrate different molecules depending on factors like life style and metabolic capability to degrade the potential harmful substances. Hence, risk assessment of the actual impact of discharges to marine biota should consider these essential biological and ecological factors.