Plastics in the ocean are of great concern nowadays, and are often referred to as the apocalyptic twin of climate change in terms of public fear and the problems they pose to the aquatic and terrestrial environment. The number of studies focusing on the ecological effects and toxicity of plastics has substantially increased in the last few years. Considering the current trends in the anthropogenic activities, the amount of plastics entering the world oceans is increasing exponentially, but the oceans have a low assimilative capacity for plastics and the near-surface layer of it is a finite space. If loading of the oceans with plastics continues at the current rate, the thin sea surface microlayer can have a substantial amount of plastics comparable to the distribution of phytoplankton, at least in the major oceanic gyres and coastal waters in the future. Also, processes like biofouling can cluster microplastics in dense fields in the near-surface layer. Plastics can contribute to the warming or cooling of the water column by scattering and attenuating incoming solar radiation, leading to a potential change in the optical and other physico-chemical properties of the water column. We propose a new notion that changes in solar radiation in the water column due to the plastics have the potential to affect the physical processes in the ocean surface and near-surface layers, and can induce climate feedback cycles. The future can be very different, if plastics evolve as one of the key players affecting the ocean physical processes and hence this is the time to tackle this puzzle with appropriate strategies or let the genie out of the bottle.

This study measured spatial distribution of marine debris stranded on beaches in South Eleuthera, The Bahamas. Citizen science, fetch modeling, relative exposure index and predictive mapping were used to determine marine debris source and abundance. Citizen scientists quantified debris type and abundance on 16 beaches within three coastal exposures (The Atlantic Ocean, Great Bahama Bank and The Exuma Sound) in South Eleuthera. Marine debris, (~2.5 cm or larger) on each beach was monitored twice between March–May and September–November 2013 at the same locations using GPS. Approximately, 93% of all debris items were plastic with plastic fragments (≤2.5 cm) being the most common. There were spatial differences (p ≤ 0.0001) in plastic debris abundance between coastal exposures. Atlantic Ocean beaches had larger quantities of plastic debris by weight and by meter (m) of shoreline. Stranded plastic may be associated with Atlantic Ocean currents associated with leakage from the North Atlantic sub-tropical gyre.

A bloom of putatively non-indigenous species (NIS) Prorocentrum shikokuense was detected for the first time in the Mediterranean Sea at the Brindisi harbor (Southern Adriatic Sea) on September 2016, in the context of EU Marine Strategy Framework Directive monitoring in the ports. This species is usually observed in the East China Sea and Japanese and Korean waters. In the Brindisi harbor this dinoflagellate reached the concentration 105 cell/L and represented from 30 to 50% of the total phytoplankton population. Besides this event, Prorocentrum shikokuense has not been found blooming until today in Mediterranean waters. This study suggests the necessity to improve the monitoring surveys in areas that are known vulnerable systems to alien and invasive species, such as ports.

This paper qualifies, quantifies and localizes seafloor marine debris (SMD) in the Moroccan portion of the Mediterranean Sea. Six scientific trawl surveys were conducted by the Moroccan Institute of Fisheries Research from 2012 to 2015 between Cape Spartel (5°W) and Saidia (2°W), during which a total of 497 kg of SMD has been collected. Statistical analysis show that the mean abundance differed between surveys, generally ranging from 26 ± 68 to 80 ± 133 kg/km2. A typology of SMD indicates that plastic represented 73% of the debris collected, followed by rubber (12%), textile (8%), metal (3%), glass (0.32%), and some unidentified materials (2.70%). Analysis of results shows that the abundance and the distribution of SMD were strongly influenced by the local anthropogenic activities and by rivers inputs. The movements and accumulations in the open sea were also shown to be influenced by the geomorphology and the hydrodynamics of the basin.

Environmental pollution with plastic is a growing problem worldwide. This study investigates the microplastic and mesoplastic pollution of Xialiao Beach in northern Taiwan. Sand from the surface (1 cm depth) was collected in a systematic manner. A total of 80 samples were taken along four transects, and plastic particles (≥1 mm) were extracted and quantified. In total, 1939 microplastic particles were recovered, with an average of 96.8 particles per 1 m2. Statistical analysis showed that the backshore had significantly more microplastic particles than the supra littoral or intertidal. Extrapolating the numbers of plastic particles found, approximately 6.8 million plastic particles (≥1 mm) weighing about 250.4 kg should be found in the surface layer of Xialiao Beach. Resampling curves were created from the data set, which showed that at minimum 20 samples should be taken to adequately estimate the mean particle abundance.

Both oil droplets and gas bubbles have simultaneously been quantified in laboratory experiments that simulate deep-water subsea releases of both live oil (saturated with gas) and additional natural gas under high pressure. These data have been used to calculate particle size distributions (50–5000 μm) for both oil and gas. The experiments showed no significant difference in oil droplet sizes versus pressure (from 5 m to 1750 m) for experiments with live oil. For combined releases of live oil and natural gas, oil droplet sizes showed a clear reduction as a function of increased gas void fraction (increased release velocity) and a weak reduction with increased depth (increased gas density/momentum). Oil droplets were reduced by a factor of 3 to 4 during simulated subsea dispersant injection (SSDI) and no significant effect of pressure was observed. This indicates that SSDI effectiveness is not dependent on water depth or pressure.

PURPOSE OF REVIEW: Many factors influence the health impact of exposure to metalliferous mine dusts and whilst the underpinning toxicology is pivotal, it is not the only driver of health outcomes following exposure. The purpose of this review is twofold: (i) to highlight recent advances in our understanding of the hazard posed by metalliferous mine dust and (ii) to broaden an often narrowly framed health risk perspective to consider the wider aetiology of the potential determinants of disease. RECENT FINDINGS: The hazard posed by metalliferous dusts depends not only on their abundance and particle size but other properties such as chemical composition, solubility, shape, and surface area, which all play a role in the associated health effects. A better understanding of the mechanisms that lead to toxicity, such as recent advances in our understanding of the role played by reactive oxygen species (ROS), can help in the development of improved in vitro models to support risk assessments, whilst biomonitoring studies have the potential to guide risk management decisions for mining communities. Environmental exposures are complex; complex geochemically and complex geographically. Research linking the environment to human health is starting to mature, highlighting the subtlety of multiple exposures, mixtures of substances, and the cumulative legacy effects of life in disrupted and stressed environments. We are evolving more refined biomarkers to identify these responses, which enhances our appreciation of the burden of effects on society and also directs us to more sophisticated risk assessment approaches to adequately address evolving regulatory and societal needs.

The Yangtze estuary is considered as an important eco-region of China, but it has been heavily disturbed by reclamation projects. We evaluated the effect of freshwater inflow on the self-restoration of macrobenthic diversity in 3-year-old vegetated, gravel, and mudflat habitats of reclaimed seaward intertidal wetlands. There was a significant self-restoration of species richness and diversity in vegetated and gravel habitats with no inflow of freshwater, but there were no significant changes in species diversity in three habitats subjected to freshwater inflow. Significant changes in community structures of macrobenthos occurred in vegetated and gravel habitats from pre- to post-restoration. Analysis of benthic health showed that gravel habitats were under moderate to high levels of disturbance in pre-restoration period. In contrast, there tended to be no evidence of disturbance in vegetated and mudflat habitats during two investigations. Restoration of macrobenthos is best achieved in vegetated habitats with on inflow of freshwater.

Although coastal dunes exhibit typical vegetation which involves species adapted to extreme environmental conditions, the mobilization and colonization by non-native species represents a challenge in its conservation and management. In this work, eight dune systems located along the Atlantico Department, Caribbean coast of Colombia were surveyed, finding within them the presence of two plant species recognized as invasive: Calotropis procera and Cryptostegia madagascariensis. The impacts of these two invasive plant species can be significant at all ecological levels in the dune systems. The above demands the implementation of urgent management actions. Eradication seems the optimal control alternative, however preventing invasive plant species from infesting new areas is more cost-effective and efficient than trying to restore the system after it is infested. Data presented in this paper is the first step in the future development of an early detection program in the study area.

The United Nations recognised the transfer of invasive species across natural barriers as one of the greatest pressures to the world's oceans and seas. The BWM Convention sets the global standards on ballast water management (BWM) requirements, while recognising that regional and local specifics have to be considered for its effective implementation. In the Adriatic Sea cross-border activities were conducted to provide for essential information/data and tools to support a regionally coordinated implementation of the BWM Convention. This special issue contains 18 publications that include results and recommendations from studying the ballast water and management issues through sampling of ballast water on vessels, risk assessment for exemptions and BWM, biological and chemical port baseline surveys and monitoring conducted in ports along the Adriatic Sea coast, oceanographic conditions, ballast water sediment issues and their management in ports, and the implementation options of the BWM Convention through the Adriatic States' environmental law and institutions cooperation. Essential data and tools to support a regional approach in the implementation of the BWM Convention were provided, and are therefore available to the administrations of the Adriatic countries to enable protection of the Adriatic Sea environment, human health property and resources from negative impacts of ballast water being discharged in the area. Data, approaches and tools provided here may be helpful in any other region to support an effective BWM Convention implementation.