We surveyed the abundance and accumulation patterns of mesoplastic marine debris (5–25mm) on 20 beaches in Korea. The mean abundance of it was 13.2items/m2, and the mean weight was 1.5g/m2. Hard plastic and Styrofoam were the dominant types. The proportions of hard plastic and Styrofoam were highly variable among the beaches, each accounting for 0–100% of the total debris on a given beach with 32% and 48.5% (by number) on average, respectively. Relatively lower abundances of mesoplastic marine debris compared with our previous studies were likely due by differences of the sampling areas within the beach. The samples of this research were selected from backshore, middle line, and water edge whereas they were selected from high strandline and backshore in our previous studies. It should be considered when discussing the level of mesoplastic marine debris.

Contaminated sediment samples were collected from the Eastern Province, Saudi Arabia for isolation of pyrene- and phenanthrene-degrading bacteria by enrichment method. Four isolates were morphologically characterized as Gram-negative rod strains and 16S rRNA sequence analysis revealed the isolates as closely related to Pseudomonas aeruginosa, P. citronellolis, Ochrobactrum intermedium and Cupriavidus taiwanensis. Degradation of the polycyclic aromatic hydrocarbons (PAHs) by the latter three strains was investigated in liquid cultures. Results of concentration reduction analyzed with gas chromatography show that P. citronellolis_LB was efficient in removing phenanthrene, degrading 94% of 100ppm in 15days while O. intermedium_BC1 was more efficient in pyrene-removal, degrading 62% in 2weeks. Furthermore, bacterial growth assessment using optical density and population counts revealed the latter as more suitable for microbial growth analysis in PAH-containing cultures. In conclusion, the isolated bacterial strains could be further developed for efficient use in biodegradation of PAH.

As the representative semi-enclosed bay of China, Bohai Bay has experienced severe eutrophication in recent decades. Monitoring data from 1995 to 2013 were analysed by generalized additive models (GAMs) to explore the temporal variations in nutrients concentrations, nutrient ratios, chlorophyll a (Chl a) concentrations and the responses of Chl a to the changes in nutrients in the spring and summer. The results showed that dissolved inorganic nitrogen (DIN) decreased from 1995 to 2000 but increased after 2000 in both the spring and summer, and soluble reactive phosphorus (SRP) decreased while the molar nitrogen/phosphorus (N/P) ratios (DIN to SRP) increased over the last two decades. Generally, P-limited phytoplankton growth was observed in the spring and summer and DIN was identified as the main pollutant constituent in Bohai Bay. Furthermore, negative correlations were found between DIN and Chl a in summer in Bohai Bay.

The aim of the present study was to evaluate the hazard from shipwrecks on communities by a holistic approach taking into account different effects on biological communities. Multibeam and Remotely Operated Vehicles surveys recorded ecological assessment of fish and benthic species on three shipwrecks flooded during the Second World War on Maërl beds habitats in the strait of Sicily. Pollution levels of a wide range of chemicals of ecotoxicological concern were also measured in sediments and in fish species from different trophic levels. Statistical analysis evidenced significant differences among pollutant levels between both sediments and fish collected in shipwreck sites and controls. Concerning fish, significant effects due to the vessel's cargo type and flooding position are recorded. In spite of that, our results underline that shipwrecks are also a hotspots of biodiversity and a habitat for preservation strategies in marine ecosystems that need to be monitored.

The Environmental Protection Agency (USEPA) has identified Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) as hazardous air pollutants. In this study, BTEX sampling was conducted at 20 sites during summer 2015 and winter 2016 in Yazd. Concentrations of BTEX were analyzed using a gas chromatograph with a flame ionization detector (GC-FID). In addition, ozone formation potential (OFP) and the health risks of BTEX were calculated. Spatial mapping was accomplished using the Kriging method. The obtained concentrations of total BTEX ranged from 8 to 560 μg/m3. The highest average individual values belonged to toluene and xylene (38 ± 42 and 41 ± 45 μg/m3, respectively). Seasonal variation showed a downward trend from summer to winter. The peak BTEX emissions occurred in the evenings, due to rush hour traffic and meteorological factors. Spatial analysis showed that the maximum levels of BTEX occurred on high traffic roads or near fuel stations. Significant correlation coefficients between benzene and other BTEX compounds revealed that BTEX were emitted from main sources including gasoline vehicles and stations. The mean ratio of toluene/benzene (T/B) in summer (1.8) was more than winter (1.4). The seasonal changes in T/B ratio possibly were attributed to photochemistry, meteorology, and emission aspects. The OFP values were 720 ± 729 and 375 ± 319 μg/m3 in summer and winter, respectively. OFPs, ranked maximum to minimum, were as follows: xylene > toluene > ethylbenzene > benzene. Although the values of the non-cancer risk of BTEX were under permissible recommended level, a cancer risk still exists because of high values of airborne benzene.

The present work analysed the characteristics of aerosol optical, physical properties over Thiruvananthapuram, a coastal site in southern part of India using Sky-radiometer (Model POM-02, Prede Co. Ltd, Japan) for a period 2011–2015. The lowest value of AOD was found during winter season which was followed by monsoon season. The highest value of AOD was found in pre-monsoon. The Angstrom Exponent which characterizes the size of the aerosols, decreases from January to June and increases from June to December months. The monthly back trajectory analysis using HYSPLIT describes the source of air masses for the station. The fine mode particles are dominant during winter season, which may be associated with the anthropogenic emissions and long range transport. A gradual increase in the coarse mode aerosol load was found from pre-monsoon season to the monsoon season, because of the large air mass coming from the ocean. A decrease in coarse mode aerosol was found during the post-monsoon period, due to the preferential washout of coarse mode particles during monsoon season. The result showed the dominance of mixed type aerosols during all seasons. The C1 cluster originating from Bay of Bengal contributed 29.8% of ensemble of trajectories, C2 cluster from Arabian Sea 31.9%, C3 cluster from the Indian Ocean (Northern hemisphere) 18.0%, and C4 cluster Indian Ocean (Southern hemisphere) 20.3%.

The behaviours of PAHs (containing 2–6 aromatic rings) in the Pearl River estuary were examined each month in 2011. This study was designed to investigate the abundance of 16 priority PAHs and their response to the seasonal dynamics of anthropogenic activities and hydrological cycles. Monthly mean concentrations of ∑16PAHs in water and suspended particulate matter (SPM) were 88.31ng/L and 252.31ng/L respectively, with higher concentrations in the wet season (April to September). Heavy precipitation in the wet season resulted in relatively increased PAH input via riverine discharges and atmospheric deposition. Seasonal variations in suspended sediment concentration (SSC), temperature and salinity have considerably affected the PAH phase association. Higher SSC in the wet season contributed to higher concentration of the PAHs in SPM, and higher temperature and lower salinity facilitated desorption from SPM. The PAH sources were largely attributed to vehicular emissions, coal combustion and coke ovens.

Coastal nursery habitats are essential for the renewal of adult fish populations. We quantified the availability of a coastal nursery habitat (shallow heterogeneous rocky bottoms) and the spatial variability of its juvenile fish populations along 250km of the Catalan coastline (France and Spain). Nurseries were present in 27% of the coastline, but only 2% of them benefited from strict protection status. For nine taxa characteristic of this habitat, total juvenile densities varied significantly between nursery sites along the coastline, with the highest densities being found on the northern sites. Recruitment level (i.e. a proxy of nursery value) was not explained by protection level, but it was moderately and positively correlated with an anthropization index. Patterns of spatial variations were taxa-specific. Exceptional observations of four juveniles of the protected grouper Epinephelus marginatus were recorded. Our data on habitat availability and recruitment levels provides important informations which help to focus MPA management efforts.

The toxicity of the antifouling biocides Irgarol 1051, Diuron, Chlorothalonil, Dichlofluanid, Sea-nine 211, Copper pyrithione, Zinc pyrithione, Ziram and Zineb were evaluated on Nitzschia pungens and Artemia larvae. Results showed that EC50 for Irgarol 1051 was 0.586μgl−1 was the strongest effect on N. pungens following by Copper pyrithione (4.908μgl−1), Ziram (5.421μgl−1), Zinc pyrithione (5.513μgl−1), Diuron (6.640μgl−1), Zineb (232.249μgl−1), Sea-nine 211(267.368μgl−1), Chlorothalonil (360.963μgl−1) and Dichlofluanid (377.010μgl−1) in 96h. In Artemia larvae, the biocides were evaluated the LC50 for larval survivals at 48h. Sea-nine 211 and Copper pyrithione were 0.318 and 0.319mgl−1. Chlorothalonil, Zinc pyrithione and Ziram were 2.683, 3.147 and 4.778mgl−1. Irgarol 1051, Diuron, Zineb and Dichlofluanid were 9.734, 30.573, 41.170 and 154.944mgl−1. These results provide baseline data concerning the toxicity of antifouling biocides against marine environment.

Our aim was to quantify microplastic ingestion by fish assemblages in two tropical Brazilian estuaries and to evaluate whether biological and ecological factors influence the ingestion of microplastics by fish species. Of 2233 fish from both estuaries (from 69 species) examined in this study, 9% of the individuals (24 species) had microplastics in their gut contents. Microplastic ingestion occurred irrespective of fish size and functional group. The diet of fish species was analyzed based on prey items identified in the fish's full stomach contents and five feeding guilds were defined. Microplastics were common throughout all feeding guilds. Low (average ingestion values 1.06±0.30 items/total fish) but widespread occurrence among estuaries also indicates proliferation of microplastic pollution. Our findings highlight the need to focus on assemblage level studies to understand the real magnitude of the problem and emphasize the urgency of mitigation measures directed at microplastic pollution in estuarine ecosystems.