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The mussel Perna perna was used to monitor and assess areas suspected of oil contamination by transplanting animals from unimpacted to impacted sites and vice versa. The deployment lasted for three months during which total PAH were measured in seawater samples collected every 15days. PAH concentrations were determined in mussel tissue monthly. The lysosomal neutral red assay and the condition index were used as biomarkers of the adverse biological effects. The PAH concentration in mussels at unimpacted sites, prior to deployment was ca. 100μgkg−1 but increased to 300μgkg−1 after three months at the contaminated site. Mussels transplanted to the uncontaminated site showed a decrease from 380 to 80μgkg−1. Significant changes in lysosomal stability occurred within one month of the beginning of the transposition; in contrast condition indexes were not correlated with the observed changes in PAH concentration. [Copyright &y& Elsevier]

Abstract: On June 2013 a workshop at the University of Siena (Italy) was organized to review current knowledge and to clarify what is known, and what remains to be investigated, concerning plastic litter in the sea. The content of the workshop was designed to contribute further to the European Marine Strategy Framework Directive (MSFD) following an inaugural workshop in 2012. Here we report a number of statements relevant to policymakers and scientists that was overwhelming agreement from the participants. Many might view this as already providing sufficient grounds for policy action. At the very least, this early warning of the problems that lie ahead should be taken seriously, and serve as a stimulus for further research. [Copyright &y& Elsevier]

Abstract: Thousands of toxic chemicals, many of which pollute marine ecosystems, potentially cause diseases, but building a consensus view of the significance of human body burdens of environmental chemicals is proving difficult. Causative mechanisms are often lacking. Older members of the population, of which there are increasing numbers worldwide, accumulate higher body burdens than the young, and may be especially at risk. It also remains unclear when crucially sensitive periods for chemical exposures occur across the life course. Very early exposures may lead to diseases much later on. The current lack of robust science upon which to base high quality expert advice is hampering effective policymaking that leads to further reductions in marine pollution, greater protection of marine life and lowering of risks to human health. [Copyright &y& Elsevier]

Norwegian coastal waters are subject to PAH contamination from electrochemical industries such as aluminium smelters. Evidence of PAH exposure has been established in fish and bivalves. The present study tests the applicability of a novel crustacean PAH exposure biomarker to a PAH contamination gradient in the field (Karmsund Strait, SW Norway). Fluorescence analysis of urine samples collected from crabs at each site revealed 1-OH pyrene “equivalent” levels (indicative of pyrogenic PAH contamination) decreased with increasing distance from a point source of pyrogenic PAH (a large aluminium works). The assay was shown to be suitable for the detection of PAH exposure in wild crustacean populations, for discriminating between contaminated and clean sites and is also sufficiently sensitive to detect gradients of PAH contamination. The method provides a rapid, inexpensive and non-destructive measure of biologically available PAH in crustaceans. [Copyright &y& Elsevier]

The European Marine Board recently published a position paper on linking oceans and human health as a strategic research priority for Europe. With this position paper as a reference, the March 2014 Cornwall Oceans and Human Health Workshop brought together key scientists, policy makers, funders, business, and non governmental organisations from Europe and the US to review the recent interdisciplinary and cutting edge research in oceans and human health specifically the growing evidence of the impacts of oceans and seas on human health and wellbeing (and the effects of humans on the oceans). These impacts are a complex mixture of negative influences (e.g. from climate change and extreme weather to harmful algal blooms and chemical pollution) and beneficial factors (e.g. from natural products including seafood to marine renewable energy and wellbeing from interactions with coastal environments). Integrated approaches across disciplines, institutions, and nations in science and policy are needed to protect both the oceans and human health and wellbeing now and in the future. [ABSTRACT FROM AUTHOR]

The investigation aimed primarily at understanding the PAH record in inter-tidal mussel tissues and evaluating the bivalve performance as a bioindicator for oil contamination. The species Perna perna was used as test organism since it is abundantly distributed in coastal areas of the Americas, Africa and elsewhere. The study was carried out in Guanabara Bay and comprised two observation phases: phase one included seasonal sampling in 8 sites, whereas in phase two 4 sites were examined over 4 years. Among the 35 determined PAH (60–90 μg kg−1 up to 4000–6000 μg kg−1) alkylated homologues predominated by more than 80%. The PAH profile in inter-tidal mussels is largely petrogenic with high contribution of dibenzothiophenes (DBT) and phenanthrenes (Ph). The prevailing petrogenic fingerprint, confirmed by diagnostic ratios, is linked to the properties of the inter-tidal habitat, which favors exposure to oil films. C2DBT/C2Ph and C3DBT/C3Ph ratios, however, show a wide range of values uncorrelated to specific oils. Micronucleus frequencies are significantly related to PAH concentrations, especially to those of alkylated homologues. Genotoxic expression appears at concentrations as low as 300 μg kg−1 ∑ 35 PAH. [Copyright &y& Elsevier]

Increasing numbers of industrial, agricultural and natural chemicals are present in sewage effluent and are known to elicit toxic effects in laboratory exposures, but little is known of their combined sub-lethal effect in the field. In this study, a combination of esterase activity and ventilation rate assays was performed to determine the neurological and physiological function of the freshwater crustacean Asellus aquaticus (L.) at sites above and below a sewage treatment works (STW). Cholinesterase and carboxylesterase activities were significantly inhibited (n=8, P<0.05) and ventilation rates increased (n=8, P=0.0001) in A. aquaticus at STW sites compared to those from reference sites, indicating a decrease in neurological and physiological function. The ecological relevance of these findings for the population dynamics of the organisms in the field is discussed. [Copyright &y& Elsevier]

Understanding how biomarkers relate to each other on exposure to particular contaminants in different species is key to their widespread application in environmental management. However, few studies have systematically used multiple biomarkers in more than a single species to determine the variability of sublethal effects of a particular contaminant. In this study, three marine invertebrates, the shore crab Carcinus maenas, the common limpet Patella vulgata and the blue mussel Mytilus edulis, were exposed over 7 days in the laboratory to environmentally realistic concentrations of the priority pollutant copper. A combination of molecular, cellular and physiological biomarkers was measured in each organism to detect the toxic effects of copper. Biomarkers included lysosomal stability (neutral red retention), neurotoxicity (acetylcholinesterase activity), metabolic impairment (total haemolymph protein), physiological status (heart rate) and induction of protective metallothionein proteins. P. vulgata was the most sensitive to copper with significant effects measured in all biomarkers at concentrations of 6.1 μg Cu l−1. In C. maenas, cellular and neurotoxic endpoints were affected significantly only at 68.1 μg Cu l−1. Exposure to copper also induced metallothionein production in crabs. Over a 7-day exposure period, M. edulis was the most tolerant species to copper with significant effects being observed at the cellular level only at 68.1 μg Cu l−1. In all three species, cellular and neurotoxic pathways were more sensitive to disruption than physiological processes (protein and heart rate). Results illustrate how a suite of biomarkers applied to different sentinel species can provide a ‘diagnosis of stress’, whereby, effects at the molecular level can be used to interpret the level of physiological impairment of the organism. [Copyright &y& Elsevier]

Expanding industrial activity (notably oil and gas exploration) in the Arctic requires assessment of the potential impact of chemicals on marine organisms living in seawater at low temperature. The bivalve Mya truncata is common in Svalbard fjord (Norway) where it experiences low temperature throughout the year. To measure the impact of polycyclic aromatic hydrocarbons (PAH) on M. truncata, the responses of three biomarkers [total oxyradical scavenging capacity-assay (TOSC), plasma membrane stability of haemocytes and respiration rates] were investigated from bivalves exposed to sediment contaminated with a PAH mixture (crude oil). After two weeks of exposure to the contaminated sediment, TOSC showed no change. The high TOSC value (4010±1339 unit mg−1 protein) of Mya truncata (control group) is thought to protect biomolecules with a low turnover rate efficiently in a low food availability environment. In the exposed bivalves, the haemocyte cellular membranes were significantly destabilised compared with controls (P<0.05). Respiration rate of control and PAH-exposed individuals (0.055±0.020 mg O2 dw−1 h−1) was similar and relatively low as is typical for polar bivalves, reflecting a strategy to minimise energy expenditure to cope with 9 months of starvation. Bioaccumulation of PAH by M. truncata was also low, due probably to a combination of low metabolic rate and reduced solubility of the oil compounds at low temperature. Data indicated an uptake of mainly low molecular weight compounds (two and three ring molecules). A good correlation of logBAFlipid (bioaccumulation factor) and logKow (octanol/water partitioning coefficient) was shown (r2=0.87). Tissue sensitivity and/or functional differences (digestive gland vs. haemocytes), PAH uptake route (dietary vs. gills), the low metabolic rate of M. truncata and the low environmental temperature (reducing the bioavailability of PAH) are factors that help explain these findings. [Copyright &y& Elsevier]

Increasing industrial activity in the European Arctic has raised concerns of the potential anthropogenic impact of chemicals on this polar marine ecosystem. For the past 20 years or so, biomarkers have been developed to provide early-warning signals of detrimental impacts of chemicals on the marine ecosystem, however, most biomarker methods have been established for organisms living in temperate rather than polar waters. Little is known about biomarker responses in organisms living within the temperature range of −1.88 to +5 °C. In this study, established biomarkers from temperate studies were tested on the Arctic spider crab Hyas araneus to validate their use in polar ecosystems. H. araneus is common in Svalbard fjord (Norway), although it is a temperate water species occurring from northern Spain to Svalbard at depths from 10 to 1200 m. In this paper, the effects of oil were investigated at 2 °C via two routes: (i) injection and (ii) contaminated sediment. After 2 weeks of exposure, heart rate, oxygen consumption and total oxyradical scavenging capacity (TOSC) were measured in the same individuals. In both methods of contaminant exposure, heart rate showed a significant increase compared with the control (P<0.0001, n=7); mean heart rate values (±S.D.) of H. araneus were 49.06 (±13.72), 57.56 (±7.28) and 63.30 (±6.57) beats per minute in control, injected and sediment-treated groups, respectively. Respiration of H. araneus was not affected significantly by either oil treatment (P>0.05), but two individuals (n=8) showed a marked increase in oxygen uptake in the sediment-exposed group. The basal oxygen consumption of control H. araneus was lower (0.025 mg O2 g wet wt.−1 h−1) than reported for H. araneus living in temperate water. Although TOSC of H. araneus was not affected significantly by either exposure treatment (P>0.05) the mean TOSC value in the sediment-exposed group was lower than the control, indicating some saturation of the oxyradical scavenging system. Results indicate that although low temperature appears to be the main factor reducing the bioavailability of polycyclic–aromatic hydrocarbons, the relatively low metabolic rate of Arctic H. araneus is also implicated in decreased uptake and metabolism of oil compounds into reactive oxygen species (ROS). [Copyright &y& Elsevier]

Urine and haemolymph can be repeatedly sampled from crabs with no (or limited) damage to the organism. Their analysis offers a measure of the animals'' exposure to biologically available contaminants. Shore crabs (Carcinus maenas) were exposed to the PAHs phenanthrene and pyrene at concentrations ranging from 20 to 200 μg l−1. After 48 h, urine and haemolymph samples were taken and analysed using ELISA and UV-fluorescence spectrophotometry. High correlations were recorded between the two sets of results from the urine analyses (r2=0.83 for phenanthrene and r2=0.88 for pyrene). Contaminant concentrations were much lower in haemolymph than in the urine. Analyses of urine taken from crabs collected from clean and contaminated sites confirm the suitability of these analyses for environmentally exposed organisms. Again, a good correlation was recorded between the ELISA and spectrofluorimetric analysis (r2=0.83). In this instance, difficulties were experienced with haemolymph analyses owing to a lack of sensitivity. [Copyright &y& Elsevier]

Industrial activities, notably oil and gas industries, are expanding in the Arctic. Most of the biomarkers were developed using temperate organisms living at temperatures above 10 °C. Little is known about the biomarker responses of organisms living between −1.88 and 5 °C. Therefore, assessment of the toxicity of chemicals to cold-water adapted species is required. In this study, the Arctic scallop, Chlamys islandicus, was selected as a key species for bio-monitoring because of wide distribution in Arctic waters and its commercial value. Test animals, stored in seawater at 2 °C, were injected with benzo(a)pyrene (diluted in cod liver oil 5 mg ml−1) in the adductor muscle every 24 h for four days giving a final dose of 0, 74 and 90.6 mg kg−1 wet weight for control, low and high dose, respectively. The biomarkers used were total oxyradical scavenging capacity (TOSC) in the digestive gland and cell membrane stability of haemocytes. TOSC values were significantly reduced (ca. 30%) in exposed groups (P<0.05), indicating a depletion in oxyradical molecular scavengers. The antioxidant defences appeared to be overwhelmed by the reactive oxygen species as the plasma membranes of haemocytes were destabilised (P<0.05) probably due to lipid peroxidation. These data indicate that reactive oxygen species (ROS) were produced by Arctic scallops via the metabolisation of benzo(a)pyrene at 2 °C. [Copyright &y& Elsevier]