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The objective of this review is to summarize information on microfibers in seawater and sediments from available scientific information. Microfibers were found in all reviewed documents. An heterogeneous approach is observed, with regard to sampling methodologies and units. Microfibers in sediments range from 1.4 to 40 items per 50 mL or 13.15 to 39.48 items per 250 g dry weight. In the case of water, microfibers values ranges from 0 to 450 items·m − 3 or from 503 to 459,681 items·km − 2 . Blue is the most common color in seawater and sediments, followed by transparent and black in the case of seawater, and black and colorful in sediments. Related with polymer type, polypropylene is the most common in water and sediments, followed by polyethylene in water and polyester in water and sediments. Some polymers were described only in water samples: high-density polyethylene, low-density polyethylene and cellophane, whilst only rayon was reported in sediments. [ABSTRACT FROM AUTHOR]

Individual parent polycyclic aromatic hydrocarbons (PAHs) were identified and quantified in samples of recent sediments at 32 stations in the Ria de Vigo (NW Spain) and its adjacent shelf by high-performance liquid chromatography and a fluorescence detector. This area suffers the pressure of nearly 500,000 inhabitants and includes a number of important marine organisms. The total concentration for the sum of the 13 PAHs quantified were in the range 28–3203 ng/g. The highest concentrations were found near the city of Vigo, where marinas and dockyards as well as highways with a high traffic flow are established. Low PAH concentrations were determined in the outermost part of the estuary, far from the anthropogenic influence. PAH isomers concentration ratios were assessed, indicating that the main source of these compounds in the whole area is pyrolysis. When compared with the EACs, threshold effect level, and probable effect level values, only the samples from the inner part of the ría can occasionally present adverse biological effects due to the PAH concentrations. [ABSTRACT FROM AUTHOR]

Abstract: The distribution of aliphatic and aromatic hydrocarbons was determined in surface sediments collected at 36 stations along the Galicia continental shelf (NW Spain), following the Prestige oil spill. Sampling was performed in December 2002, just after the accident, and in February and September 2003. Concentrations of PAHs (∑13 parent components) were in the range of 0.9–422μg/kgdw, the highest values being close to coastal urban areas (e.g. Pontevedra and A Coruña), whereas in the stations of the area most heavily impacted by the spill (off Costa da Morte) concentrations were in the range of 14.8–89.6μg/kgdw, with a certain predominance of alkylated compounds, which may suggest a mixture of petrogenic and pyrolytic sources. The detailed study of petrogenic molecular markers (e.g. steranes and triterpanes) showed the occurrence of an old (weathered) petrogenic chronic pollution in the shelf sediments but not of the Prestige oil, with the possible exception of few stations in the area of Costa da Morte. This was attributed to the heavy nature of the spilled oil that was barely dispersed in the water column and mainly stranded on the coast or sedimented in the form of oil patches. The addition of increasing amounts of fuel oil to a representative sediment sample showed that the molecular indices were indicative of the presence of the Prestige oil when the amount was above 1g/kg of sediment. The toxicity of selected samples (showing the higher PAH concentrations) was tested using the bivalve embryogenesis bioassay. Embryogenesis success reached high values in all cases (80–88%, with 86% in the control), indicating a lack of toxicity in the sediments and supporting the conclusion that the patchiness of the fuel eventually reaching the seafloor reduced its impact on the benthic communities of the Galician shelf. [Copyright &y& Elsevier]

Ten global harbours were assessed for sediment quality by quantifying the magnitude of anthropogenic change and ecological risk. Anthropogenic change (enrichment) was high for Derwent River and Sydney estuary, moderate for Santander Harbour, Rio de Janeiro and Dublin Port, slight for Hong Kong, minimal for Darwin. All 10 enrichment indices used showed similar results. Derwent River sediment was rated at high ecological risk, followed by Sydney and Santander estuaries with moderate risk. Auckland and Darwin sediments exhibited minimal ecological risk and sediment in the remaining harbours (Dublin, Hong Kong, Ravenna, Ria de Vigo and Rio de Janeiro) were assessed at slight ecological risk. The extraordinary variety of environments and types/quantities/qualities of data investigated resulted in as much a critique and development of methodology, as an assessment of human impact, including unique techniques for elemental normalisation and contaminant classification. Recommendations for an improved technical framework for sediment quality assessment are provided. Unlabelled Image • Ten global harbours were assessed for anthropogenic change (AC) and ecological risk (ER) • AC was high for Derwent River, Santander and Sydney estuaries • AC was moderate for Rio de Janeiro and Dublin Port, slight for Hong Kong, minimal for Darwin. • Derwent River sediment was rated at high ER, Sydney and Santander estuaries with moderate risk. • An improved technical framework for sediment quality assessment is provided. [ABSTRACT FROM AUTHOR]