Marine risk assessment: linear alkylbenzenesulponates (LAS) in the North Sea

The fate of linear alkylbenzenesulponates (LAS) in estuaries and coastal areas of the North Sea has been characterized with simple environmental models. The predicted concentration range in the estuaries around the North Sea (0.9-9 microg LAS l(-1)) was validated by monitoring data (1-9 microg LAS l(-1)). In offshore sites of the North Sea, it is estimated--and experimentally verified for a few sites--that the LAS concentration is below analytical detection limit (i.e., 0.5 microg LAS l(-1)). The effects of LAS on marine organisms have been reviewed. For short-term acute tests, there was no significant difference (p = 0.83) between the mean LC50 values of freshwater and marine organisms (mainly pelagic species tested, 4.1 and 4.3 mg LAS l(-1), respectively). For longer-term chronic tests, it appeared that the sensitivity (mean no-observed effect concentration (NOEC) value) of marine and freshwater organisms (0.3 and 2.3 mg LAS l(-1), respectively) was significantly different pt-test = 0.007). The predicted no-effect-concentrations (PNEC) were 360 and 31 microg LAS l(-1), for freshwater and marine pelagic communities, respectively. Given that the maximum expected estuarine and marine concentrations are 3 to > 30 times lower than the PNEC, the risk of LAS to pelagic organisms in these environments is judged to be low.     

Contamination of Caribbean coastal waters by the antifouling herbicide Irgarol 1051

Irgarol 1051 is a s-triazine herbicide used in popular slime-resistant antifouling paints. It has been shown to be acutely toxic to corals, mangroves and sea grasses, inhibiting photosynthesis at low concentrations (>50 ng l(-1)). We present the first data describing the occurrence of Irgarol 1051 in coastal waters of the Northeastern Caribbean (Puerto Rico (PR) and the US Virgin Islands (USVI)). Low level contamination of coastal waters by Irgarol 1051 is reported, the herbicide being present in 85% of the 31 sites sampled. It was not detected in water from two oceanic reference sites. In general, Irgarol 1051was present at concentrations below 100 ng l(-1), although far higher concentrations were reported at three locations within Benner Bay, USVI (223-1,300 ng l(-1)). The known toxicity of Irgarol 1051 to corals and sea grasses and our findings of significant contamination of the Northeastern Caribbean marine environment by this herbicide underscore the importance of understanding, more fully, local and regional exposure of reef and sea grass habitats to Irgarol 1051 and, where necessary, implementing actions to ensure adequate protection of these important ecosystems.     

Seasonal variation of dissolved metals in inshore waters of the Menai Straits

Many surveys of trace contaminants of seawater are based on the supposition that the situation is static. Little is known about seasonal fluctuations in the concentrations of these contaminants and less about the cause of this variation. Fluctuation in freshwater carrying metals or sediment that will trap contaminants, changes in movements of water masses in the sea, as well as the use of trace metals by marine organisms, are all contributory factors.     

What is the future fate of estuaries given nutrient over-enrichment,freshwater diversion and low flows?

Freshwater inflow is central to the definition of estuaries and if we lose control of the quantity of freshwater flow or discharge (including seasonal timing) to estuaries, then freshwater water quality has the potential to become a moot issue in estuarine ecosystems (Definition of estuaries: estuaries (aestus = tide) are physico-chemically, geomorphically, and biotically diverse ecosystems. Although numerous definitions of estuaries exist, we prefer the following: an estuary is a partially enclosed coastal water body in which freshwater runoff, often seasonally and episodically pulsed, dilutes salty ocean water and the biotic structure is influenced by dynamic tidal action and associated salinity gradients and reef building organisms and wetlands influence development and evolution of ecological structure and function (see for expanded definition)).     

Plankton of the Baltic estuarine ecosystems with emphasis on Neva Estuary: a review of present knowledge and research perspectives

Different levels of eutrophication and pollution in the Baltic coastal waters in general, and in estuaries particularly define variations in the buffering capacity of ecosystems of these important filter zones between rivers and the adjacent Baltic Proper. Phyto- and zooplankton in the estuaries form important components of the pelagic food webs that participate in producing and structuring the matter, energy, and information fluxes in the ecosystems. Due to salinity gradients, estuaries provide a large variety of aquatic habitats for native populations of marine, brackish and fresh water plankton species. Non-indigenous planktonic species that expand their bio-geographical range and invade the Baltic coastal ecosystems also find favourable environments, establish permanent populations there, and impact aboriginal ecosystems. The dynamics of abundance, species diversity, population structure, productivity of planktonic communities, and peculiarities of trophic interactions in different Baltic estuaries are influenced by a number of common environmental factors. Being measured on the unified basis and monitored, changes (or stability) of structural and functional parameters of plankton communities can serve as indicators of alterations to the ecosystems. Comparative analyses and quantitative estimates of long-term changes in phyto- and zooplankton can contribute to evaluation of functional response of Baltic coastal ecosystems to anthropogenic stress. Both theoretical (modeling) and empirical studies of interactions within plankton communities aimed at the assessment of the role of planktonic organisms in water quality regulation, and applicability of these data for the evaluation of the status of ecosystems and their management can be considered as major goals for the future investigations in Baltic estuaries.     

Spatio-temporal comparisons of imposex status and tissue organotin concentration in the whelk Reishia clavigera collected along the coasts of Dapeng Bay and Daya Bay,Shenzhen, China

Organotin compounds (OTs) have caused widespread adverse effects on marine organisms. As no local restrictions on OT-based antifouling paints have been implemented in China, high concentrations of OTs still occur in coastal environments. In this study, we measured the imposex status and tissue concentrations of OTs in the whelk Reishia clavigera collected along the coast of Dapeng Bay and Daya Bay of Shenzhen, China in 2013. Our results showed that all female whelks suffered from the onset of imposex. The highest concentration of total OTs was 27,756 μg kg⁻¹ dry weight in the samples collected from Shuitousha. Triphenyltin was the most predominant residue, accounting for more than 97.8% of total OTs across all sites. Compared with the results from previous studies, the marine environment of this region is still heavily contaminated with OTs. Therefore, a tightened control is necessary to regulate the use and release of OTs in China.     

Human health benefits supplied by Mediterranean marine biodiversity

This paper summarizes the overall benefits supplied by Mediterranean marine biodiversity to human health and highlights the anthropogenic and environmental causes that are threatening these benefits. First, the Mediterranean Sea is a valuable source of seafood, which is an important component of the so-called “Mediterranean diet”. This type of diet has several health benefits, including cardio and cancer protective effects, which are attributed to the high intake of seafood-derived n-3 (omega-3) fatty acids. Second, the Mediterranean marine organisms, particularly the benthic ones, have furnished a large variety of bioactive metabolites, some of which are being developed into new drugs to threat major human diseases such as cancer. Third, the Mediterranean coastal areas provide environments for practising maritime leisure activities that provide physical and psychological benefits to users. Despite all this, fishing, tourism, contamination and sea warming are deteriorating this rich marine ecosystem, which needs to be protected to assure human welfare.     

Geochemistry of organic carbon and nitrogen in surface sediments of coastal Bohai Bay inferred from their ratios and stable isotopic signatures

Total organic carbon (TOC), total nitrogen (TN) and their δ(13)C and δ(15)N values were determined for 42 surface sediments from coastal Bohai Bay in order to determine the concentration and identify the source of organic matter. The sampling sites covered both the marine region of coastal Bohai Bay and the major rivers it connects with. More abundant TOC and TN in sediments from rivers than from the marine region reflect the situation that most of the terrestrial organic matter is deposited before it meets the sea. The spatial variation in δ(13)C and δ(15)N signatures implies that the input of organic matter from anthropogenic activities has a more significant influence on its distribution than that from natural processes. Taking the area as a whole, surface sediments in the marine region of coastal Bohai Bay are dominated by marine derived organic carbon, which on average accounts for 62±11% of TOC.     

Contaminants still high in top-level carnivores in the Southern California Bight: levels of DDT and PCBs in resident and transient pinnipeds

Highly industrialized areas, such as the Southern California Bight, often have high levels of contaminants in marine sediments, which can cause chronic exposure to organisms long after their use has ceased. tDDT and tPCB were analyzed in the blubber of 145 stranded pinnipeds that died at local marine mammal centers between 1994 and 2006. Resident species (California sea lion and Pacific harbor seal) had significantly higher concentrations of tDDT and tPCB than the transient species (northern elephant seal). Adult female California sea lions had significantly lower concentrations of tDDT and tPCB than pups, yearlings, and adult males. Concentrations of both tDDT and tPCB in California sea lions significantly declined over time, but did not change in northern elephant seals. Current concentrations of tDDT and tPCB in California sea lions and harbor seals are among the highest values reported worldwide for marine mammals and exceed those reported to cause adverse health effects.     

Organotin levels in Nazaré canyon (west Iberian Margin, NE Atlantic) and adjacent coastal area

Organotin compounds (OTs) are ubiquitous in the marine environment and high concentrations (μg g(-1) range) in sediments from different coastal areas around the world have been reported. However, few reports have described the OTs contamination status in the offshore and deep sea environment. This work investigated organotin levels in Nazaré canyon for the first time. Levels of monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPT), triphenyltin (TPT), dioctyltin (DOT) and trioctyltin (TOT) were quantified in sediment samples from the upper flanks of the canyon and from the adjacent coastal area. TBT levels detected in the canyon flanks are about two to three orders of magnitude lower than those found in the coastal area. Nevertheless, when quantifiable, TBT levels in the canyon samples were higher than the Environmental Assessment Criteria set for TBT in sediments by the OSPAR Commission indicating that at those locations negative ecological impacts are likely to occur.     

Integrated use of biomarkers (superoxide dismutase, catalase and lipid peroxidation) in mussels Mytilus galloprovincialis for assessing heavy metals' pollution in coastal areas from the Saronikos Gulf of Greece

Mussels are used as sentinel organisms and bioindicators to evaluate the toxic effects of chemical pollutants in marine organisms, especially heavy metals, representing an important tool for biomonitoring environmental pollution in coastal areas. Antioxidant defence enzymes play an important role in cellular antioxidant defence systems and protect from oxidative damage by reactive oxygen species (ROS). Indigenous mussels Mytilus galloprovincialis of the Saronikos Gulf of Greece were used for monitoring heavy metal pollution in three polluted sites in the area and in one unpolluted site. Seasonal variations of the activity of antioxidant defence enzymes, superoxide dismutase (SOD) and catalase (CAT), as well as lipid peroxidation (LP) were measured as biomarkers in a period of three years in relation to concentrations of trace metals in their gills and mantle and compared to mussels from an unpolluted sampling site. SOD activity increased at least 2 fold at the polluted sites when compared to the control site (the high activity was recorded in the spring time). CAT activity was increased 2-3 times at the polluted sites, with high activity in the winter and spring time, compared to the control site. LP concentration was twice higher at the polluted sites, following the same seasonal pattern. Trace metals contents in mussels collected at polluted sites were 3-4 fold higher compared to the control site and showed moderate variations along the months, with a winter maximum followed by a summer pre-spawning minimum matching the seasonal trends of temperature and salinity. Our results showed that metal pollution in the Elefsis Bay (the most polluted coastal area) causes relatively medium levels of oxidative stress in tissues of mussels due to cellular oxy-radical generation. This study, which is the first in the area, showed that seasonal variations of the activity of antioxidant defence enzymes and LP concentrations in mussels can be used as potential biomarkers of toxicity for long-term monitoring in marine coastal ecosystems.     

从沉积物特征谈太湖的演变

通过太湖湖底淤泥层中的微体古生物及其物理化学分析,在西太潮W1孔发现多门类海相化石。海相化石出现的时间约在1100—5000aB.P.之间。据此提出西太湖在全新世期间曾遭受海侵,因而支持了太湖形成于泻湖的说法,同时,还提出海水进入太湖的时间,比以往学者推测的早2000多年。     

Plastic in the Thames: A river runs through it

Although contamination of the marine ecosystems by plastics is becoming recognised as a serious pollution problem, there are few studies that demonstrate the contribution made by freshwater catchments. Over a three month period from September to December 2012, at seven localities in the upper Thames estuary, 8490 submerged plastic items were intercepted in eel fyke nets anchored to the river bed. Whilst there were significant differences in the numbers of items at these locations, the majority were some type of plastic. Additionally in excess of 20% of the litter items were components of sanitary products. The most contaminated sites were in the vicinity of sewage treatment works. While floating litter is visible, this study also demonstrates that a large unseen volume of submerged plastic is flowing into the marine environment. It is therefore important that this sub-surface component is considered when assessing plastic pollution input into the sea.     

The occurrence and distribution of pharmaceutical compounds in the effluents of a major sewage treatment plant in Northern Taiwan and the receiving coastal waters

The pharmaceutical residues in waste water from the largest sewage treatment plant (STP) in Northern Taiwan and in seawater around the effluent discharged area were determined. An environmental risk assessment for the marine environment was conducted based on the environment risk quotient (ERQ). The concentrations of the analyzed compounds in STP influent and effluent were generally higher than those found in coastal seawater. Relatively higher values were found at the estuarine mouth and the discharged area, suggesting that the STP effluent is a point source. The removal efficiency and half life of the analyzed compounds were 6.3-46.8% and 3-18 days, respectively. The ERQ value theoretical calculation was generally greater than 1. However, when the measured concentrations replaced the predicated concentrations, the ERQ values were considerably lower than 1. Therefore, our results call for a re-evaluation of the risks posed by pharmaceuticals to coastal marine ecosystems in Northern Taiwan.     

Inter-annual variability of wet season freshwater plume extent into the Great Barrier Reef lagoon based on satellite coastal ocean colour observations

Riverine freshwater plumes are the major transport mechanism for nutrients, sediments and pollutants into the Great Barrier Reef (GBR) lagoon and connect the land with the receiving coastal and marine waters. Knowledge of the variability of the freshwater extent into the GBR lagoon is relevant for marine park management to develop strategies for improving ecosystem health and risk assessments. In this study, freshwater extent has been estimated for the entire GBR lagoon area from daily satellite observations of the Moderate Resolution Imaging Spectroradiometer (MODIS) between 2002 and 2010. To enable a reliable mapping of freshwater plumes we applied a physics-based coastal ocean colour algorithm, that simultaneously retrieves chlorophyll-a, non-algal particulate matter and coloured dissolved organic matter (CDOM), from which we used CDOM as a surrogate for salinity (S) for mapping the freshwater extent.     

Marine environmental impact due to mining activities of El Salvador copper mine,Chile

Marine environmental impact as a result of copper mine tailing dumping in the sea is studied at Chañaral (North of Chile). These dumpings, from the copper mine El Salvador, have hindered harbour activities, caused geomorphological coastal modifications and affected seriously marine coastal ecosystems and recreational activities. At the old dumping site, Chañaral Bay (1938–1974), nearly 150 million tons of fine sediments were accumulated. Tailing discharges at the new dumping site, Caleta Palito, about 8 km north of Chañaral Bay are accumulating approximately at the rate of 25 000 tons of fine sediments per day, plus unknown quantities of chemicals (Cu, As, CN^?). From January 1975 to July 1976, this site has received over 13 million tons of sediments which has caused deterioration of the marine coastal environment, reduction in light penetration and high mortalities among marine invertebrates, fishes and algae.     

Source speciation resolving hydrochemical complexity of coastal aquifers

There is a growing concern of seawater intrusion to freshwater aquifers due to groundwater overexploitation in the eastern coastal belt of Southern India. The problem becomes complex in the regions where industrial effluents are also contaminating the freshwater aquifers. In order to understand the hydrochemical complexity of the system, topographic elevation, static water level measurements, major ion chemistry, ionic cross plots, water type contours and factor analysis were applied for 144 groundwater samples of shallow and deep sources from Quaternary and Tertiary coastal aquifers, located within the industrial zone of 25 km² area near Cuddalore, Southern India. The ionic cross plots indicates dissolution of halite minerals from marine sources and seawater mixing into inland aquifers up to the level of 9.3%. The factor analysis explains three significant factors totaling 86.3% of cumulative sample variance which includes varying contribution from marine, industrial effluent and freshwater sources.     

Comparative petroleum hydrocarbons levels and biochemical responses in mussels from hydrothermal vents (Bathymodiolus azoricus) and coastal environments (Mytilus galloprovincialis)

Aliphatic hydrocarbons and PAHs in the whole soft tissues of Bathymodiolus azoricus from three Mid-Atlantic Ridge hydrothermal vents (Menez-Gwen, Lucky Strike and Rainbow), and Mytilus galloprovincialis from three contaminated coastal sites in South Portugal were analysed, and its effects on the digestive gland microsomes mixed-function oxygenase system (MFO) were assessed.Aliphatic hydrocarbons levels were present in the same magnitude in both coastal and hydrothermal environments, while the UCM (unresolved complex mixture) for coastal mussels were higher than in vent mussels. In general, significantly higher PAHs concentrations were found in coastal mussels, compared to B. azoricus where low molecular weight PAHs (2–3 rings) represented the majority of PAHs contrarily to what was observed in M. galloprovincialis. The MFO components were present in both mussel species, and were detected in vent mussels for the first time. However this system seems to have different roles in species from these contrasting environments. In coastal mussels MFO responded to hydrocarbon contamination while response in hydrothermal organisms appeared to be related mainly to endogenous factors.     

Assessing sound exposure from shipping in coastal waters using a single hydrophone and Automatic Identification System (AIS) data

Underwater noise from shipping is a growing presence throughout the world's oceans, and may be subjecting marine fauna to chronic noise exposure with potentially severe long-term consequences. The coincidence of dense shipping activity and sensitive marine ecosystems in coastal environments is of particular concern, and noise assessment methodologies which describe the high temporal variability of sound exposure in these areas are needed. We present a method of characterising sound exposure from shipping using continuous passive acoustic monitoring combined with Automatic Identification System (AIS) shipping data. The method is applied to data recorded in Falmouth Bay, UK. Absolute and relative levels of intermittent ship noise contributions to the 24-h sound exposure level are determined using an adaptive threshold, and the spatial distribution of potential ship sources is then analysed using AIS data. This technique can be used to prioritize shipping noise mitigation strategies in coastal marine environments.