The distribution, congener patterns, possible sources, and ecological risks of polybrominated diphenyl ethers (PBDEs) were investigated in the surface sediments of 20 fishing ports along the coast of Bohai Sea. PBDEs are widespread pollutants in fishing ports, and the total concentrations of 14 PBDEs (∑₁₄PBDEs) are 4.23–20.59 ng/g with a mean value of 12.56 ng/g. BDE-209 was the dominant congener. The fishing ports with high PBDE concentrations were located near Liaohe River, Haihe River, manufacturing plants of BFRs near Laizhou Bay, and tipping areas of marine garbage. BDE-209 and BDE-47 were the most important congeners that discriminate PBDE pollution. The possible sources of PBDEs included the input of commercial mixtures of penta-BDE, octa-BDE, and deca-BDE, the debromination of BDE-209, and the atmospheric transport of the low brominated diphenyl ethers. The ecological risks in surface sediments were attributed to the congeners of tetra-BDE, penta-BDE, and deca-BDE with low or medium levels.

Phosphorus (P) plays key role in phytoplankton primary production in coastal water. In this study, seawater samples collected within China's Leizhou Peninsula coastal waters from October 2017 to July 2018 were examined to determine the seasonal variation, speciation, and transport flux of total dissolved phosphorus (TDP) linked to hydrographic features. TDP concentration and speciation had significant seasonal variations (P < 0.01), and the annual mean TDP concentration was 0.42 ± 0.25 μmol·L⁻¹. High concentrations of TDP occurred in coastal waters adjacent to Zhanjiang Bay and Jianjiang River estuary, whereas low TDP concentrations were found across large offshore areas. Dissolved inorganic and organic P were the main TDP bulk species in different seasons, comprising up to 55.5 ± 7.9% and 46.5 ± 22.6%, respectively. The Beibu Gulf was annually subjected to 3.5 × 10⁹ mol flux of TDP through the Qiongzhou Strait. Coastal currents, river plumes, and human activities were responsible for the dynamic variations in P species.

The hydrothermal products of the Clam hydrothermal field from the Okinawa Trough were analyzed by gas chromatography–mass spectrometry to determine abundances of hydrocarbons. The n-alkanes in the hydrothermal products conformed to a bimodal distribution and exhibited an odd-to-even predominance of high molecular weight and an even-to-odd predominance of low molecular weight n-alkanes with maxima at C₁₆ and C₁₈. The total concentration of n-alkanes in hydrothermal sediment was much higher than that in hydrothermal sulfide and altered rock. The carbon isotopic value of individual n-alkanes in hydrothermal sediment was slightly higher than that in pelagic sediment. The concentrations and individual carbon isotopic compositions of n-alkanes suggest that the n-alkanes in hydrothermal products may be mainly the result of the metabolic activity of submarine microorganisms. Additionally, the present results suggest that the abiogenic contribution to source of hydrocarbons in hydrothermal products of the Clam hydrothermal field from the Okinawa Trough should not be ignored.

Nitrogen (N) from anthropogenic sources has been identified as a major pollutant of the Great Barrier Reef (GBR), Australia. We developed a conceptual framework to synthesise and visualise the fate and transport of N from the catchments to the sea from a literature review. The framework was created to fit managers and policymakers' requirements to reduce N in the GBR catchments. We used this framework to determine the N stocks and transformations (input, sources, and outputs) for ecosystems commonly found in the GBR: rainforests, palustrine wetlands, lakes, rivers (in-stream), mangroves and seagrasses. We included transformations of N such as nitrogen fixation, nitrification, denitrification, mineralisation, anammox, sedimentation, plant uptake, and food web transfers. This model can be applied to other ecosystems to understand the transport and fate of N within and between catchments. Importantly, this approach can guide management actions that attenuate N at different scales and locations within the GBR ecosystems. Finally, when combined with local hydrological modelling, this framework can be used to predict outcomes of management activities.

Major sources of pollution from shipping to marine environments are antifouling paint residues and discharges of bilge, black, grey and ballast water and scrubber discharge water. The dispersion of copper, zinc, naphthalene, pyrene, and dibromochloromethane have been studied using the Ship Traffic Emission Assessment Model, the General Estuarine Transport Model, and the Eulerian tracer transport model in the Baltic Sea in 2012. Annual loads of the contaminants ranged from 10⁻² tons for pyrene to 100 s of tons for copper. The dispersion of the contaminants is determined by the surface kinetic energy and vertical stratification at the location of the discharge. The elevated concentration of the contaminants at the surface persists for about two-days and the contaminants are dispersed over the spatial scale of 10-60 km. The Danish Sounds, the southwestern Baltic Sea and the Gulf of Finland are under the heaviest pressure of shipborne contaminants in the Baltic Sea.

As evidenced from literature, exposure to non-lethal concentrations of dissolved copper (Cu²⁺) and copper nanoparticles (CuO NPs) promotes blue mussels susceptibility to various bacterial infections. We study whether pre-exposure (3.5 h) with CuSO₄ (100 μg Cu L⁻¹) and CuO NPs (1000 μg Cu L⁻¹) will result in infection of M. edulis L. with pathogenic microalga Coccomyxa sp. under field conditions. In May – September 2019, cages were installed in the site Metis-sur-Mer, St. Lawrence Estuary (QC, Canada) where the native mussel population is known to be infected with the pathogen. Untreated and pre-exposed mussels were grown for up to 130 days. Only the mussels pre-exposed to copper were infected by Coccomyxa. This finding allows proposing that occurrences of Coccomyxa-infected mussels worldwide might have an association with water pollution with xenobiotics. Pre-exposure of caged mussels to copper, as a protocol monitoring for other infectious agents, can be recommended to test.

At present plastic residues has become grave threat to the environment. Microplastics are plastic residues with a size <5 mm, due to their small size it is very difficult to remove them from water bodies, sediments and air with available techniques. Nanoplastics are different in size range as nanoplastics are smaller than 1 μm in size. This review is an attempt to gather an insight towards microplastic and its associated point of concerns. The review will highlight some of the methods appropriate for microplastics sampling and techniques for its identification in environmental samples. Some of the sampling methods include sieving, filtration, visual sorting, digestion, density separation. While, identification techniques in practice are SEM-EDS, FTIR, NIR, Raman, NMR spectroscopy, etc. Still there is a need and scope for development of more economical and portable techniques in this direction.

Recently, the quickly growing population living in urban location has caused numerous conflicts related to increase in water demand and water pollution. In urban areas, the surface water bodies allow runoffs and storms and in addition act as wastewater drainage pathways. Mostly, the imperfect separation of rainwater and clean wastewater has made large quantities of wastewater discharged into the surface water, resulting in serious pollution. There are many treatment methods for the polluted water bodies such as coagulation, filtration, and ecological floating bed which are related to nutrient removal. The above listed methods are usually capable in reducing pollution load. Wastewaters generated from two sources such as point source (domestic and industries) and non-point source (agricultural and storm water runoff). Finally it reaches nearby water bodies and the abovementioned methods are to be frequently employed in a wastewater treatment plant to remove nutrients. Most of the pollutants in the vastly polluted water are in dissolved forms; hence, an appropriate treatment method relevant to the design and development of the integrated multistage reactor with extended wastewater treatment is reviewed in this paper. Evaluating the accumulation, precipitation, retention, and removal of phosphorus, along with removal of nitrogen, is discussed in brief.

Southeast Alaska sea otters (Enhydra lutris) have had a rapid rise in their population. As they feed primarily on sessile prey, they are excellent sentinels for examining metals contamination. Objectives of this study on sea otters were to determine: (1) concentrations of metals in different tissues; (2) whether metals biomagnify from stomach contents (i.e., the prey) to other tissues; (3) whether selenium and mercury concentrations indicate an overall health benefit or risk; and (4) if metals concentrations in tissues vary with body size. Brain, kidney, gonad, liver, and stomach contents were collected from freshly harvested sea otters in Icy Strait, Alaska, and analyzed for arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), total mercury (THg), and selenium (Se). Metals concentrations varied significantly, and some were biomagnified, with livers and kidneys harboring the highest concentrations. Lead and arsenic appeared to be readily excreted. This study represents baseline metals concentrations to assist in monitoring the health of sea otters.

The constantly growing production of synthetic materials and their presence in the environment gradually transform our Blue Planet into the Plastic One. Microplastics (MPs) enlarge significantly their surface during fragmentation processes. Undoubtedly, nanoplastics (NPs), emerging contaminants, and the Plastisphere, the total available surface of debris, are currently on the edge of science. Although a few research are dedicated to the analysis of MPs and NPs from the physical and chemical point of view, there is a lack of the correlation between the material characterization and the microbiological data. The ecological approach, covering the description of numerical antibiotic or metal resistance bacteria, dealing with toxicological issues or biodegradation, is of great importance. This paper creates the bridge between the material science approach and the eighth continent (as sometimes Plastisphere is called). It points out that the Plastisphere significance will grow within the coming years and it should not be regarded as one ecological niche, but a set of different ones. As the properties mainly depend on the surface morphology, its numerical characterization will be the base for the classification purposes to better describe and model this phenomenon. Apart from concerning the currently important issues of NPs and the Plastisphere, this paper presents the emerging area of research namely the numerical approach to their characterization. This proposal of an interdisciplinary approach to the classification of the Plastisphere's types might be interesting for the members of different scientific communities: nanotechnology, material science and engineering, chemistry, physics, ecology, microbiology, marine microplastics or picture analysis.