The characteristics of phytoplankton assemblages were analyzed by the Utermöhl method in the southern Yellow Sea in summer, 2008. A total of 113 species (including varieties and forms), belonging to 51 genera and 3 phyla, were identified. Diatom was the most dominant group. The dominant species included Eucampia zoodiacus, Leptocylindrus danicus, Chaetoceros affinis, Thalassionema nitzschioides, Skeletonema costatum, Paralia sulcata and Chaetoceros tortissimus, which were eurytopic and temperate species. The cell abundance of phytoplankton ranged from 0.04 to 620.08 cells·mL−1 with an average of 27.52 cells·mL−1. Horizontally, the cell abundance showed a decreasing trend from the south to the north. In terms of vertical distribution, the values in surface and subsurface water layers were higher than those in bottom water layers. Results of correlation analysis showed that phytoplankton cell abundance was positively correlated with water temperature, ammonia and nitrite concentrations, and negatively correlated with salinity and silicate concentration.

This study estimates for the very first time plastic litter levels in sea cucumbers (Echinodermata, Holothuroidea) sampled in situ and their intakes from sediments in three different rocky bottom habitats (slides, cliff, banks) settled in Salina Island (Aeolian Archipelago). Macroplastic were never recorded while meso- and microplastics were identified in all sediment (81–438 items/kg d.w.) and animal samples (1.8–22 items/ind.). Plastic intakes by sea cucumbers resulted frequently associated to the size range included within 100–2000 μm. Over than 70% of ingested plastic litter is represented by the size fraction >500 μm. Sediment/animals ratios % are included 2.7 ± 2.0% in studied habitats with a selective intake of fragments occurring in slides. Furthermore, results support the occurrence of selective ingestion of plastic litter by holothurians in natural environments underlining the role of these species in microplastic transfer from abiotic towards biotic compartments of the marine trophic web.

Commercial marine fish, crustacean, and mollusc samples were collected from Sanmen Bay and its adjacent areas to investigate the accumulation of heavy metals in various species of marine organisms and evaluate the potential health risk for local consumers. The results indicated significant variations in metal contents among species. The highest concentrations of studied metals were found in molluscs, followed by crustaceans and fish. The first metal group of arsenic (As), cadmium, copper, and zinc were associated by their relatively high concentrations in the tissues of marine organisms, whereas chromium, mercury, and lead were identified the other group with low concentrations. Human health risk evaluation indicated that the exposure doses of most elements for coastal people were safe, except for As, which scored a high total target hazard quotient and target cancer risk value. Potential health risk of heavy metal exposure from seafood consumption should not be ignored.

This study evaluated the PAH bioavailability from Santos Bay (Brazil) in 4 species of fish, using PAH biliary metabolites. The collection was done monthly, between July and December, in three different regions of Santos Bay. The metabolites were analyzed through a high performance liquid chromatograph with fluorescence detectors. Total metabolites concentrations ranged from 65.5 to 589μgg−1 of bile, evidencing PAH bioavailability on Santos Bay. Levels of phenanthrene and benzo[a]pyrene metabolites were in the classification range of areas moderate contaminated. Those concentrations were lower in Nebris microps and higher in Sphoeroides testudineus (p<0.05). Naphthalene metabolites concentrations did not differ significantly among fish species and were in the classification range of low contaminated areas. There were no significant spatial and temporal differences in levels among sampled areas. These results are environmentally important given the high levels of urbanization and the absence of biomonitoring data in this area.

In this study, concentrations of heavy metals, rare earth elements (REEs), Uranium (U) and Thorium (Th) of the actinide group were determined from Linggi estuary sediment samples by neutron activation analysis (NAA) and inductive coupled plasma - mass spectrometry techniques. The geo-accumulation (Igeo) and ecological risk index (Ri) values were calculated to identify the quality status of Linggi estuary sediments. Results indicated Linggi estuary was polluted by arsenic (As), lead (Pb) and antimony (Sb). REEs, U and Th showed significant increase of concentration in Linggi estuary sediments. Ri of Linggi estuary was categorised as low to considerable ecological risk, which indicates no significant to moderate effect on the majority of the sediment-dwelling organisms. Correlation matrix and principal component analysis assessed pollution sources to be both natural and anthropogenic.

This is the first study on the distribution and characteristics of plastic debris found in the sediments of Rameswaram Island, Gulf of Mannar, India. Studies on the distribution of plastics and microplastic content in highly populated coral islands and their impact on the coral ecosystem are very scarce. For this purpose, marine sediment samples were collected from 20 locations along the coastal areas of the study region. The distribution and characterization study was carried out by visual examination followed by FTIR spectroscopy. The results showed abundance of white-colored and irregular-shaped plastic debris in this study area. Polypropylene was identified as a dominant polymer variety, followed by polyethylene, polystyrene, nylon, and polyvinyl chloride. Tourist activities and fishing practices were found to be the possible sources of the microplastic debris. Additionally, the distribution of the plastics was found to be dominantly controlled by the aeolian process and the nature of the coast.

Severe microplastic pollution from anthropogenic activities in coastal zones presents an imminent risk to marine ecosystems. In this study, abundant microplastics (15–12,852 items kg−1) with sizes ranging between 0.16 and 5.0 mm were extracted from 17 sediment samples collected in sandy beaches and mangrove wetlands of the Qinzhou Bay, Guangxi Province, Southwest China. Three types of microplastics (i.e. polystyrene, polypropylene, and polyethylene) were identified with Fourier transform infrared (FTIR) spectroscopy analysis. These detected microplastics were characterized by different colors (white, transparent, yellow, green, red, and blue) and shapes (fragment, fiber, and sphere). Microplastics were concentrated on supratidal beaches and wetlands outside of mangrove, and less abundant on intertidal beaches and inside of mangrove wetlands. Meanwhile, high microplastic concentrations were observed near mollusk farms. The spatial distribution and chemical speciation indicated that microplastics were derived from disintegration of large plastic debris (e.g., Styrofoam buoys used to support mollusk rafts) abandoned by aquaculture industry. Further, coastal vegetation (e.g. mangrove) could trap microplastic particles.

The Gulf of Pozzuoli includes the former second largest Italian steelworks of Bagnoli. The REE, Y, Th and Sc pollution in sediments of the Gulf of Pozzuoli was determined. Ce, La, Nd and Pr had the highest percentage distribution of rare earth elements normalized respect to chondrite with 31.19, 28.35, 19.51 and 8.41% individually. It was observed a marked enrichment of these elements, from west to the east from 26.39 to 111.04 mg/kg and from onshore to offshore from 31.67 to 217.74 mg/kg. The output of the principal component analysis revealed that the REE were mainly of anthropic origin being clearly linked to that of PAHs, metals and organic matter. This, together with their distribution patterns, highlighted the role of the former Bagnoli metallurgical plant in the pollution of the gulf.

A two-dimensional model was used to reconstruct scenarios related to the mass fish death phenomenon that occurred along the Central Coast of Vietnam. First, a Weather Research Forecasting model was used to simulate the wind field during April 2016, and was then used as an input to the two-dimensional (2D) model. Second, the calibration of the 2D model showed high conformity in both the phases and amplitude between the simulated and observed water levels. The simulation results of two scenarios, S1 and S2, were highly recommended for explaining the mass fish death phenomenon that occurred along the coast from Ha Tinh Province to Thua Thien-Hue Province. The calculated results of water quality data combined with the toxic concentration measured in fish will ultimately enable the simulation of the delimiting pollution zones and will facilitate response solutions when a similar phenomenon occurs in the future.