The Marine Strategy Framework Directive (MSFD) is the piece of legislation with which the EU aims to achieve Good Environmental Status (GES) of its seas. This Directive requires Member States (MSs) to set up and implement Programmes of Measures (PoMs) to achieve this goal. This paper presents a catalogue as well as the analysis of the 535 measures proposed by the eight Mediterranean EU MSs to combat pollution and non-indigenous species and contribute to the GES of the Mediterranean Sea. The results reiterate the need for better coherence and coordination between MSs, also with non-EU countries in the preparation of the next iteration of PoMs. Only 5% of the measures applied have an effect beyond MSs´ marine waters jurisdiction, and a fifth of them lack linkages with any ecosystem component. The results point to gaps, while desired goals and recommendations will help policy makers to implement the and conceptualise measures.

This study investigates the frequency of microplastic (MP) ingestion and the relationship between microplastics in the guts of two commercial fish species in Iceland (cod; Gadus morhua and saithe; Pollachius virens) and the weight, length, gut fullness, and condition index (CI) of the fish. MPs were found in 20.5% of the cod (n = 39) and 17.4% of the saithe (n = 46). There was no significant correlation between gut fullness nor CI and findings of MPs, indicating that, especially in large individuals, MPs are not retained to a large extent, and if so, the CI is most likely not affected. A difference was found in fish length between fish containing plastic and fish without plastics. Further studies such as this must be conducted in all water ecosystems if we are to fully understand the impact that MP's are having at the individual, population, species, and ecosystem levels.

A long-term monitoring during dredging and non-dredging periods was performed. Total and dissolved Cu and Pb concentrations, DGT-labile Pb, ultraphytoplankton abundance and structure were monitored at four sites: dredging site, dumping site (inside/outside of a geotextile bag) and reference site. During the reference period (non-dredging), an increasing contamination in Pb, Cu and a progressive shift from Synechococcus to photosynthetic picoeukaryotes dominance was observed from reference to dumping site. Pb concentrations were significantly higher during dredging period, pointing out sediment resuspension as Pb major source of contamination. Unlike Pb, Cu concentrations were not statistically different during the two periods. Dredging period did not impact on ultraphytoplankton abundance and structure but influence heterotrophic prokaryotes abundance. Sediment resuspension is therefore a major driver of chemical and biological qualities in Toulon Bay. Furthermore, although the geotextile bag reduces particulate transport of the dredged sediment, the transport in the dissolved phase remains a major problem.

The temporal and spatial variability of heavy metal distribution was studied in an Arctic fjord (Hornsund, Spitsbergen). Seawater from 8 sampling stations and 3 sampling depths was collected in 6 successive months and used for measurement of dissolved and particulate heavy metal concentrations. Salinity and temperature profiles were determined prior to sampling and water masses were classified according to their properties. Isotopic lead composition (²⁰⁶Pb/²⁰⁷Pb and ²⁰⁶Pb/²⁰⁸Pb ratios) was studied to find the sources of Pb to the fjord seawater. Hornsund seawater was contaminated with the studied heavy metals (particularly during the summer months). Extremely high contamination with Cd was measured (dissolved up to 488 ng·L⁻¹, while particulate up to 303 ng·L⁻¹), which is most probably connected to high atmospheric deposition. Depending on the season and the region, metal distribution was modified by glacier meltwater and surface run-off discharges, melting of fast ice, direct atmospheric deposition, transport of sea salt, intrusion of Atlantic water, sediment re-suspension, as well as re-mobilization.

Plastic pollution is one of the major issues impacting on the marine environment. Plastic polymers are known to leach industrial chemicals and associated contaminants. In this review, we focused on assessing the global distribution and concentration of two polystyrene-derived contaminants, hexabromocyclododecanes (HBCDs) and styrene oligomers (SOs), in marine sediments and seawater. Overall, most of the studies were carried out in Asia, North America, and Europe. Relatively high concentrations of these contaminants are generally attributed to the proximity of urban cities, plastic industries, polystyrene pollution, and aquaculture. Moreover, the concentrations in sediments are many times higher than in seawater. HBCDs were found to be a negligible risk to marine biota when compared to the ecotoxicological endpoints. However, realistic concentrations of SOs could compromise the wellbeing of certain species in highly polluted sites. The future perspectives and research were discussed.

A risk assessment framework for direct exposure of residual additives and monomers present in ingested plastic particles, including microplastics, in the Danish marine environment, was presented. Eight cases of different polymer types and product groups were defined that represent the most significant exposures, and thus potential high-risk cases, towards marine organisms. Risk Quotients (RQ) were calculated for three trophic levels, i.e. pelagic/planktonic zooplankton: copepod, benthopelagic fish: Atlantic cod and seabird: northern fulmar. European and Danish Environmental Quality Standard (EQS) values were used as Predicted No-Effect Concentrations (PNEC). RQ larger than unity, indicating potential risks, were found for copepod and cod (pelagic community) and the flame-retardant pentabromodiphenyl ether (PeBDE) used in polyurethane (PUR), the biocide tributyltin (TBT) present as impurity in polyvinylchloride (PVC) and PUR, and the flame-retardant hexabromocyclododecane (HBCDD) used in expanded polystyrene (EPS). A potential risk was found for fulmar (secondary poisoning) and PeBDE used in PUR.

Compared to open sea environments, there is still limited knowledge about microplastic levels in semi-enclosed systems such as coastal lagoons. This work aims to assess the levels of MPs in the waters of an urban lagoon (Bizerte lagoon, northern Tunisia) and to study the effects of environmental factors on their distribution and abundance. Average concentration of total MPs was found to be 453.0 ± 335.2 items m⁻³. The upper 25 cm water layer of the lagoon is most likely to contain ~16.99 × 10⁹ MPs items (which correspond to a total mass of 42.47 t). Fibers were the primary MPs types encountered, and most of MPs particles identified were white and clear-colored. Polyethylene and polypropylene were the predominant polymer types in Bizerte lagoon. Among the various potential plastic sources of MPs, unmanaged domestic plastic wastes are likely to be the major source of plastic pollution in the lagoon. Several environmental factors appeared to influence the distribution and density of MPs in the lagoon waters. These information contribute to better understand the dynamics of MPs in lagoons and to develop environmental management actions.

Marine litter is one of the most pressing problems of our time and a major threat to ocean health; much of it comes from land-based sources, including from beachgoer activities. This study investigates how product design could influence littering behaviors of beachgoers when applied to beach trash cans (TCs). Over the course of six weeks three differently designed TCs were placed on a Mediterranean Sea tourist beach in Israel while observers tracked the behavior of 536 nearby groups (“entities”) of beachgoers. Researchers analyzed: a) entities' locational choices; b) materials discarded in the TCs; and c) littering behaviors around the TCs. Based on the data collected, a “motivating” TC design performed best, encouraging the highest level of beachgoer interaction. Further research is needed in more and varied beach contexts, but this type of initial interdisciplinary research suggests how the design discipline could contribute to preventing marine litter from land-based sources.

Nitrogen fixation and its ecological regulation are poorly understood in the tropical estuaries, which are highly influenced by anthropogenic disturbances. In this study, we investigated the role of nutrient stoichiometry in the diversity, abundance and activity of N₂-fixing bacterial community and their seasonal variations in the water column of a tropical eutrophic estuary (Cochin estuary). The N₂ fixation rates in the estuary ranged from 0.1 to 2.0 nmol N₂ l⁻¹ h⁻¹, with higher activity during post-monsoon and lower during monsoon. The rates are appeared to be primarily controlled by dissolved inorganic nitrogen and phosphorous (N:P) ratio. Clone library analysis of nitrogenase (nifH) gene revealed that the major N₂ fixing phylotypes belong to Cluster I and Cluster III diazotrophs. The overall findings of this study suggest that monsoon induced seasonal changes in nutrient stoichiometry control the distribution and activity of diazotrophs in a tropical estuary.

The potential ecological impacts of elevated suspended sediments (SS) in coastal areas due to human activities remain unclear. In particular, physiological response of benthic fish to SS exposure in polluted environment has not been documented. We determined sub-lethal toxicity of polluted and non-polluted SS to olive flounder. Test organism was exposed to varying concentrations of SS (0–4000 mg L⁻¹) and real-time oxygen consumption rate (OCR) was measured for 12 h. The early-juvenile was sensitive to SS, particularly at >500 mg L⁻¹, but late-juvenile was tolerant up to 4000 mg SS L⁻¹. Metal polluted SS (HQₘₑₜₐₗ > 1) increased OCR in general, particularly at >1000 SS mg L⁻¹. Combined effect of copper and SS exposure on fish was either synergistic or antagonistic. Overall, potential adverse effect of polluted SS on fish greatly varied at different life stage and/or by metal pollution gradients.