Sixteen USEPA priority polycyclic aromatic hydrocarbons (PAHs) were analyzed by gas chromatography–mass spectrometry. Twenty-three samples were collected from the surface sediments of Qinhuangdao coastal wetlands in this survey. This research aimed to identify the PAHs contamination level, composition pattern, pollution sources, and assess the ecological risk of PAHs. The results showed that the sum of PAH concentrations ranged from 341.61ng/g to 4703.80ng/g (mean: 1367.80ng/g), which is higher than the reported values for different wetlands worldwide. Five- and four-ring PAHs (34.08% and 32.97% of Ʃ16PAHs, severally) were predominant in the wetland sediment. The PAH source distribution in the surface sediments was determined using diagnostic ratio and PCA/MLR. Consequently, multiple PAH sources were found. Of the total PAHs, 70.01% was derived from vehicular emission, 25.73% from coke oven, and 4.26% from petroleum-based product spills. The effect range low/effect range median (ERL/ERM) values indicated a low toxicity risk level. However, the DBahA concentrations exceeded the ERL level, and even the ERM level, in some stations. The mean effects range–median quotient (M-ERM-Q) suggests a low ecological risk for the PAHs, but a medium risk for some stations in the coastal wetland sediments.

Man-made coastal debris pollution is a growing concern for Taiwan. In 2004, Taiwanese environmental organizations led by the “Society of Wilderness” began gathering data on 19 categories of debris items collected during cleanup events. We present our analysis of the resulting 12-year dataset collated from 541 events held between October 2004 and December 2016. In total, 904,302 items weighing 131,358.3 kg were collected, and 63.6% and 27.2% of items were made of either plastic or plastic mixed with other materials, respectively. The five most commonly recorded debris categories were plastic shopping bags, plastic bottle caps, disposable tablewares, fishing equipment, and plastic drinking straws. We estimated that during the 12-year period on average between 3.7 and 7.9 million items weighing 560–1110 metric tons polluted Taiwan's coastline. We offer recommendations for improving the quality of data collected during Taiwan's cleanup events and report some policy changes due partly to previous reports of this dataset.

The vertical pattern of pelagic ciliate communities was observed at eight layers in the Chukchi Sea and the northern Bering Sea of the western Arctic Ocean during the summer sea-ice reduction period (August 5 to August 24, 2016). A total of 44 ciliate species were identified, with seven species dominated the communities in the water column. Multivariate and univariate analyses demonstrated that: (1) community structures of ciliates vary significantly among eight water depths; (2) variations in the vertical distribution of ciliates were significantly correlated with changes in physicochemical variables, especially the ammonia; (3) the distributions of the three dominant species were significantly and positively related to the chlorophyll a and ammonia concentrations; and (4) species richness and abundance were significantly and positively correlated with the concentrations of ammonia and chlorophyll a. These results suggest that pelagic ciliates may reflect vertical variations in the water quality status of western Arctic ecosystems.

Although numerous studies have performed ecological quality status (EcoQS) assessments in aquatic ecosystems, knowledge regarding the assessment of the EcoQS of mangrove transplant wetlands is still lacking. Therefore, we investigated the influence of mangrove transplants on the EcoQS by comparing the sediment quality status and benthic quality status in mangroves with those of reference sites (Spartina alterniflora stand and mudflat). The findings confirm that the benthic quality status of mangroves was superior to those of the reference sites. Subsequently, we tested the performances of various indices (AMBI, BENTIX, H′, EX, Δ⁺, and Ʌ⁺). BENTIX, H′, EX and Ʌ⁺ seemed be more suitable than AMBI and Δ⁺ for assessing the benthic quality status. The results also confirm that mangrove transplants may not facilitate or restrain the accumulation of heavy metals (except Cu and Hg) in sediments. Moreover, mangrove transplants posed a low ecological risk.

Ashes settling into the sea from volcanic explosions expose suspension-feeding species to reduced seston quality. Adults and juveniles of the mussel Mytilus chilensis were exposed for 15days to the phytoplankton Isochrysis galbana together with various concentrations of ashes. We then quantified impact on survival and physiology. Although no individuals died during the experiment, by the end of the study clearance rates and oxygen consumption rates had decreased substantially, and tissue weight of mussels exposed to the highest ash concentrations declined substantially. Gills showed no physical damage, but did show abundant mucus secretion in response to ash particles. Moreover, as the relative proportions of microalgae to ash in the diet decreased, individuals showed increasing preferential ingestion of microalgal particles. Increased ash content in the diet altered physiological rates and activated distinct particle selection with a high production of pseudofeces and high energy costs, with potential long-term consequences.

The decline of the European eel (Anguilla anguilla L., 1758) population throughout Europe has been partially attributed to pollution. As glass eel estuarine migration may represent a considerable threat, the impact of mercury (Hg) contamination at this stage was evaluated through an in situ experiment (7days). Total Hg (tHg) bioaccumulation was evaluated concomitantly with erythrocytic nuclear morphology alterations: erythrocytic nuclear abnormalities assay (ENA), frequency of immature erythrocytes (IE) and the erythrocytic maturity index (EMI). The ENA results suggested a genotoxic pressure at the most contaminated sites, in line with the tHg increase. The EMI data, together with IE frequency, showed that fish exposed to high levels of Hg exhibited alterations of haematological dynamics, translated into an erythropoiesis increment. Despite the presence of these compensatory mechanisms, the present findings suggest a harmful impact of Hg on genome integrity at this early development stage, potentially affecting eels' condition and ultimately the population sustainability.

The abundance, composition and sources of marine litter were determined on beaches located in the seven countries of the Adriatic-Ionian macroregion, namely Albania, Bosnia and Herzegovina, Croatia, Greece, Italy, Montenegro and Slovenia. A total of 70,581 marine litter items were classified and recorded through one-year long surveys carried out in 31 sites. The average litter density of 0.67 items/m2 found within this study is considered to be relatively high. The beaches investigated differed in terms of human-induced pressures; their majority is classified either as semi-urban or semi-rural, while very few beaches could be characterized as urban or remote/natural. The majority of litter items were made of artificial/anthropogenic polymer materials accounting for 91.1% of all litter. Litter from shoreline sources accounted for 33.4% of all litter collected. The amount of litter from sea-based sources ranged in the different countries from 1.54% to 14.84%, with an average of 6.30% at regional level.

Dioxins have global concerns because of the bioaccumulation tendency and persistency in the environment. Water, seabream Pagrus auratus and seabass Dicentrarchus labrax samples were collected from Abu Qir, Alexandria to evaluate the concentration of dioxin. Fourier Transform Infrared Spectrometer (FTIR) and molecular modeling was applied for elucidating the molecular structure of fish samples. Furthermore, HPLC with UV detection was used to determine the concentration of dioxins (2,8-dichloro dibenzo-p-dioxin). RT-PCR assay was conducted to verify the expression of some immune genes in the fish species as a result of water pollution. The average detected concentrations varied from 0.2 to 1.3μg/l. Gene expression revealed that MHC class 1 and C3 were highly upregulated in liver and muscle of seabass and seabream while T2BP was highly regulated in seabass liver and seabream muscle and seabass muscle for transferrin, FTIR and molecular modeling indicate that dioxin finds its way to fish protein.

A 3D ecosystem model was used to quantify changes in water quality brought about by salmon aquaculture in the D'Entrecasteaux Channel and Huon Estuary in southeast Tasmania. Macroalgae-based integrated multitrophic aquaculture (IMTA) was simulated and showed that IMTA is capable of reducing the increased chlorophyll concentration attributable to fish farming by up to 10–15% in large areas of the region, during the season of highest production. Kelp farms (Macrocystis pyrifera) recovered between 6 and 11% of the dissolved inorganic nitrogen (DIN) input by salmon aquaculture over a nine month period, with DIN remediation increasing linearly with farm size. Under a ten-fold increase in aquaculture to very high loads, a much lower remediation effect was found for both chlorophyll and DIN. Model results indicate that IMTA could have an important impact on reducing negative effects of finfish aquaculture on water quality providing that stocking rates are not too high.