Deltares, P.O. Box 177, 2600 MH Delft, The Netherlands.
Mar Pollut Bull. 2010 Nov;60(11):2026-42. doi: 10.1016/j.marpolbul.2010.07.018. Epub 2010 Sep 17.
Given the potential environmental consequences of dumped dredged harbour sediments it is vital to establish the potential risks from exposure before disposal at sea. Currently, European legislation for disposal of contaminated sediments at sea is based on chemical analysis of a limited number of well-known contaminants for which maximum acceptable concentrations, action levels (ALs), have been set. The present paper addresses the issue of the applicability of in vitro and in vivo bioassays for hazard, risk and local impact assessment of dredged polluted sediments to be disposed of at sea. It discusses how and to what extent selected bioassays can fill in the gaps left open by chemical analysis and the way in which the bioassays may contribute to the present licensing system for disposal. Three different purposes for application were distinguished: the most basic application (A) is a rapid determination of the hazard (potential toxicity) of dredged sediments which is then compared to ALs in a licensing system. As with chemical analysis on whole sediment extracts, the bioavailability of the chemicals is not taken into account. As in vitro assays with sediment extracts are not sensitive to matrix effects, a selection of specific in vitro bioassays can be suitable fast and standardized additions for the licensing system. When the outcome of (A) does not convincingly demonstrate whether the sediment is clean enough or too polluted, further bioanalysis can help the decision making process (B). More aspects of the mostly unknown complex chemical mixtures are taken into account, including the bioavailability and chronic toxicity focusing on ecologically relevant endpoints. The ecotoxicological pressure imposed by the dredged sediments can be quantified as the potentially affected fraction (PAF) based on chemical or biological analysis of levels of contaminants in sediment or biota. To validate the predicted risk, the actual impact of dumped harbour sediments on local ecosystems (C) can be determined using a dedicated set of in vitro and in vivo bioassays as well as bio-indicators selected based on the information obtained from (A) and (B) and on the characteristics of the local ecosystem. Conversely, the local sediment impact assessment (C) can direct fine-tuning of the selection of chemical and bioassay analyses and for setting safe levels in the licensing system. It is concluded that in vitro and in vivo bioassays and biological indicators are useful tools in the process of hazard, ecotoxicological risk and impact assessment of dredged harbour sediments, provided they are consciously chosen and quality criteria for assay performance are defined.
鉴于倾倒疏浚港口沉积物对环境造成的潜在影响，在将其处置到海洋之前，确定其暴露的潜在风险至关重要。目前，欧洲关于在海洋处置污染沉积物的立法是基于对有限数量的已知污染物进行化学分析，这些污染物设定了最大可接受浓度（ALs）。本文讨论了体外和体内生物测定法在评估拟处置到海洋的疏浚污染沉积物的危害、风险和局部影响方面的适用性问题。它讨论了如何以及在何种程度上选择生物测定法可以填补化学分析留下的空白，以及生物测定法如何为现有的处置许可证制度做出贡献。区分了三种不同的应用目的：最基本的应用（A）是快速确定疏浚沉积物的危害（潜在毒性），然后将其与许可证制度中的 ALs 进行比较。与整个沉积物提取物的化学分析一样，未考虑化学品的生物利用度。由于体外测定法与沉积物提取物的基质效应不敏感，因此可以选择特定的体外生物测定法作为许可证制度的快速标准化添加物。当（A）的结果不能令人信服地证明沉积物是否足够清洁或污染太严重时，可以进一步进行生物分析以帮助决策过程（B）。更多未知的复杂化学混合物的方面被考虑在内，包括生物利用度和以生态相关终点为重点的慢性毒性。可以基于沉积物或生物群中污染物水平的化学或生物分析来量化疏浚沉积物施加的生态毒性压力，即潜在受影响部分（PAF）。为了验证预测风险，可以使用专门的体外和体内生物测定法以及基于从（A）和（B）获得的信息以及当地生态系统的特征选择的生物指标，来确定倾倒港口沉积物对当地生态系统的实际影响（C）。反过来，当地沉积物影响评估（C）可以指导在许可证制度中选择化学和生物测定分析的微调，并设定安全水平。结论是，体外和体内生物测定法和生物指标是评估疏浚港口沉积物的危害、生态毒性风险和影响的有用工具，前提是它们是有意识地选择的，并为测定性能定义了质量标准。
