Despite legislative interventions since the 1980s, contemporary concentrations of organotin compounds in marine sediments still impose restrictions on the disposal of dredged material in the UK. Here, we analyse temporal and spatial data to assess the effectiveness of the ban on the use of TBT paints in reducing concentrations at disposal sites.At a national scale, there was a statistically significant increase in the proportion of samples in which the concentration was below the limit of detection (LOD) from 1998 to 2010. This was observed for sediments both inside and outside the disposal sites. However, this temporal decline in organotin concentration is disposal site-specific. Of the four sites studied in detail, two displayed significant increases in proportion of samples below LOD over time. We argue that site-specificity in the effectiveness of the TBT ban results from variations in historical practices at source and unique environmental characteristics of each site.

Bacteria (and viruses) numerically dominate ballast water communities, but what controls their population dynamics during transit is largely unexplored. Here, bacterial abundance, net and intrinsic growth rates, and grazing mortality were determined during a trans-Atlantic voyage. The effects of grazing pressure by microzooplankton on heterotrophic bacteria during transit were determined for source port, mid-ocean exchange (MOE), and six-day-old source port ballast water. When the grazer component was removed, bacterial abundances significantly increased. Additionally, we determined that the grazer-mediated mortality for ballast water originating from ports was greater than MOE water and that mortality decreased over time for the source port ballast water. This study shows that bacterial populations in transit are controlled by microzooplankton grazing. If these findings are representative of ballast water environments, they suggest that if the grazing component is selectively removed by various treatment methods, bacterial populations may increase; this could have environmental and human health consequences.

Mussels (Mytilus galloprovincialis) from the Turkish Straits Systems were analyzed for sixteen parent polycyclic aromatic hydrocarbon (PAH) contents by high performance liquid chromatography (HPLC). This marine organism was selected because of its multitude, wide distribution, being bio indicator for the pollution and consumption by humans. Total PAH concentrations ranged from 1.2 to 589μgg−1 in Istanbul Strait, 0.94–36.4μgg−1 in Marmara Sea and 0.4–47.9μgg−1 in Çanakkale Strait during the samplings. According to the results Istanbul and Çanakkale Straits are more polluted than the Marmara Sea.

Novel photocatalysts i.e., metallic nickel and zinc oxide nanoparticles embedded in the carbon-shell ((Ni–ZnO)@C) have been used for photocatalytic splitting of seawater to generate H2. The (Ni–ZnO)@C core–shell nanoparticles having the Zn/Ni ratios of 0–3 were prepared by carbonization of Ni2+- and Zn2+-β-cyclodextrin at 673K for 2h. To increase the collision frequency of water and photoactive sites within the carbon-shell, Ni and ZnO are partially etched from the (Ni–ZnO)@C core–shell to form yolk–shell nanoparticles with a H2SO4 solution (2N). By X-ray diffraction spectroscopy, mainly Ni and ZnO crystallites are observed in the core– and yolk–shell nanoparticles. The sizes of the Ni and ZnO in the (Ni–ZnO)@C nanoreactors are between 7 and 23nm in diameters determined by TEM and small angel scattering spectroscopy. Under a 5-h UV–Vis light irradiation, 5.01μmol/hgcat of H2 are yielded from photocatalytic splitting of seawater effected by (Ni–ZnO)@C nanoreactors.

The majority of plastic debris found in the marine environment has land based sources and rivers are considered an important medium for transfer of this debris. Here we report on the quantity and composition of floating plastic debris collected from surface waters of the Tamar Estuary. This represents the first study of riverine transport of floating plastic debris into European waters during different tidal regimes. Plastics were found in a variety of forms and sizes and microplastics (<5mm) comprised 82% of the debris. The most abundant types of plastic were Polyethylene (40%), Polystyrene (25%) and Polypropylene (19%). There was a significant difference in size frequency distribution between the spring and neap tides with more fragments of larger size observed during spring tides. While it is clear that debris has accumulated on shorelines within the estuary, during our study this river did not identify as a net source or sink.

Magnetic expanded graphite (MEG) was prepared using the blended calcination method under a nitrogen atmosphere. MEG was characterized by scanning electron microscope (SEM), X-ray powder diffraction (XRD), Raman spectroscopy, and vibrating sample magnetization (VSM). Results show that the cobalt ferrite nanoparticles were uniformly and efficiently deposited on expanded graphite (EG). The saturation magnetization reached 55.05emug−1, and the adsorption capacity of MEG under the optimal condition was 35.72gg−1 for crude oil.

The level and source of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in the surface sediments from the Gorgan Bay, Caspian Sea. The sum of 16 PAHs (ΣPAH16) concentrations varied from 107.87 to 516.18ngg−1dry weight, with average value of 270.96±150.47ngg−1dry weight. Ecological risk assessment of PAHs, indicated that adverse biological effects caused by acenaphthene, naphthalene, fluoranthene and Pyrene occasionally and frequently may take place in the sediments of Gorgan Bay. PAHs source identification demonstrated that the PAHs come from mixed and pyrogenic origin.

The influence of tuna penning on soft bottom habitat present in the vicinity of tuna pens and at distances 200m and 1.5km away, was assessed by comparing attributes of macroinvertebrate assemblages and sediment quality before (November 2000, March 2001) and after (November 2001, April 2002) initiation of the activity. Results from November 2001 indicated a significant increase in sediment organic carbon and organic nitrogen, and a non-significant increase in the abundance of Capitellidae in the vicinity of the cages. Similar results were obtained 200m from the cages but not 1.5km away, where the only change was a significant increase in organic nitrogen in sediment. Results from April 2002 indicated no significant change in sediment organic carbon and organic nitrogen, however, mean sediment grain size decreased significantly in the immediate vicinity of the cages. Changes in attributes of the benthic assemblages and sediment resulted from accumulation of uneaten feed-fish on the seabed.

This study aimed to evaluate airborne meso–and–thermophilic actinomycete concentrations and their types at a wastewater treatment plant and a biosolid landfill, in Egypt. Air samples were collected at 200m upwind, and onsite and 300m downwind by using liquid impinger sampler, calibrated to draw 12.5L/min, for 20 minutes. The concentrations ranged between 0.0–7 360CFU/m3 for mesophilic, and 106–586CFU/m3 for thermophilic actinomycetes. Airborne actinomycete concentrations exceeded the suggested occupational exposure limit value of 100CFU/m3. No significant correlations were found between actinomycete concentrations onsite and 300m downwind distance. At the biosolid landfill, upwind thermophilic actinomycetes significantly differed (p<0.05) from onsite and 300m downwind. A total of 40 and 69 airborne actinomycete isolates belonging to 8 genera were identified at the wastewater treatment plant and biosolid landfill. Streptomyces were the dominant actinomycete species. Streptomyces diastaticus, Pseudonocardia compacta and Catellatospora ferruginea were only detected at the biosolid landfill site. Meso–and–thermophilic actinomycetes positively associated with relative humidity, and wind speed positively correlated with onsite thermophilic actinomycetes (r=0.65) at the biosolid landfill. Temperature showed negative effect on survivability of mesophilic actinomycetes (r=-0.8) onsite of the wastewater treatment plant. Waste application facilities increase actinomycete concentrations onsite which may consequently deteriorate air quality in the nearby areas.

Ipomoea nil (L.) Roth. cv. ‘Scarlett O’Hara’ was evaluated as a tropical bioindicator species sensitive to ozone (O3). A total of nine field experiments were performed, with 28 days of exposure each. Visible leaf injuries, carbon assimilation (Asat) and stomatal conductance (gs) were quantified and correlated to oscillations in environmental conditions and accumulated ozone exposure over a threshold of 40 ppb h (AOT40). The values of gas exchange and leaf injury continuously varied throughout the study period. Asat and leaf injury (chlorosis) were higher in spring than in others seasons. The gs was higher in autumn. The analyses of the abiotic and biotic variables revealed an opposing trend between the Asat and both leaf injury and AOT40. Ozone levels were moderate and its relationship with gs was inverse. This may be the cause of the moderate injury. ‘Scarlett O’Hara’ is sensitive to O3 and has potential as an O3 bioindicator in sub–tropical regions.