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The potential impact of dredged sediment has been assessed at sixteen areas of the high-traffic port of Vilagarcia (Northwest Spanish Atlantic coast). The assessment has been done by three weight-of-evidence tools, which integrated data on sediment characteristics and toxicity responses of Ampelisca brevicornis, Vibrio fischeri and eggs and embryos of Paracentrotus lividus. Two of the tools also represented management options regarding the disposal of dredged material. The comparison of the logic in these tools revealed essential differences in the type and the necessity of bioassays and threshold values for chemical concentrations. However, despite this difference, assessment results and the derived management options coincided in most of the sediments. The potential toxicity of sediments was relatively low especially for eggs and embryos possibly due to different contaminant availability in solid and liquid phases. The importance of a battery of toxicity tests in the dredged material quality assessment has been emphasized to avoid an underestimation of sediment toxicity for solid phase organisms, if only liquid phase responses are considered. The potential false implications, which may result from the application of the third tool, were highlighted. The strengths and weaknesses of the tools were discussed from the dredged material management perspective.

The results of sediment quality assessment by two different weight-of-evidence methodologies were compared. Both methodologies used the same dataset but as criteria and procedures were different, the results emphasized different aspects of sediment contamination. One of the methodologies integrated the data by means of a multivariate analysis and suggested bioavailability of contaminants and their spatial distribution. The other methodology, used in the dredged material management framework recently proposed in Spain, evaluated sediment toxicity in general by assigning categories. Despite the differences in the interpretation and presentation of results, the methodologies evaluated sediment risk similarly, taking into account chemical concentrations and toxicological effects. Comparison of the results of different approaches is important to define their limitations and thereby avoid implications of potential environmental impacts from different management options, as in the case of dredged material risk assessment. Consistent results of these two methodologies emphasized validity and robustness of the integrated, weight-of-evidence, approach to sediment quality assessment. Limitations of the methodologies were discussed.

The potential toxicity of sediments from various ports was assessed by means of two different liquid-phase toxicity bioassays (acute and chronic) with embryos and eggs of sea urchin Paracentrotus lividus. Performances of embryos and eggs of P. lividus in these bioassays were compared for their interchangeable applicability in integrated sediment quality assessment. The obtained endpoints (percentages of normally developed plutei and fertilized eggs) were linked to physical and chemical properties of sediments and demonstrated dependence on sediment contamination. The endpoints in the two bioassays were strongly correlated and generally exhibited similar tendency throughout the samples. Therein, embryos demonstrated higher sensitivity to elutriate exposure, compared to eggs. It was concluded that these tests could be used interchangeably for testing toxicity of marine sediments. Preferential use of any of the bioassays can be determined by the discriminatory capacity of the test or vulnerability consideration of the test subject to the surrounding conditions. © 2013 Elsevier Ltd.

The selection of the best management option for contaminated sediments requires the biological assessment of sediment quality using bioindicator organisms. There have been comparisons of the performance of different test species when exposed to naturally occurring sediments. However, more research is needed to determine their suitability to be used interchangeably. The sensitivity of two amphipod species (Ampelisca brevicornis and Corophium volutator) to sediments collected from four different commercial ports in Spain was tested. For comparison the lugworm, Arenicola marina, which is typically used for bioaccumulation testing, was also tested. Chemical analyses of the sediments were also conducted. All species responded consistently to the chemical exposure tests, although the amphipods, as expected, were more sensitive than the lugworm. It was found that C. volutator showed higher vulnerability than A.brevicornis. It was concluded that the three species can be used interchangeably in the battery of tests for integrated sediment quality assessment. © 2013 Elsevier Inc.

A new software tool for integrative sediment quality assessment is developed. The program is based on WOE methodologies which together may be used for assessing degree of contamination in marine sediment. Statistical analysis of field-collected and lab-based data is performed by means of commercial statistical software package Statistica 6.0. The designed tool provides user-friendly interface, is extremely easy in use, greatly simplifies statistical analysis process, interprets the results in text and graphical format. © 2008 Elsevier Ltd.