Determining causality of sediment toxicity is of great importance in aquatic risk assessment, but there are tremendous challenges due to joint toxicity of trace pollutants in complex sediment matrices. Two approaches, namely toxicity identification evaluation (TIE) and effect-directed analysis (EDA) have been developed. Conventional sediment TIEs take the advantage of environmental relevance by using whole organism bioassays; however, they suffer from lack of effective methods for specifically identifying major contributors as it typically only evaluates contaminant class rather than specific contaminants. Alternatively, EDA is a powerful tool in identifying causes of sediment toxicity with sophisticated fractionation and chemical analysis of targeted and non-targeted non-polar organic toxicants, but it is not always environmentally relevant due to the use of in-vitro bioassays and exhaustive solvent extraction. An integrated TIE and EDA method would provide an environmentally relevant and toxicant specific approach to effectively determine causality of sediment toxicity by combining the merits of the two methods. Bioavailability-based extraction and dosing techniques are recommended to be incorporated into the integrated method to improve the accuracy of toxicity diagnosis. Besides considering bioavailability in the integrated TIE and EDA approach, the premise of adverse outcome pathways should also be considered. Generally speaking, both TIE and EDA have focused on adverse effects at cellular and organism levels. The addition of trait-based approaches in screening multiple toxicological endpoints helps to extend effects on cellular and organism levels to population level, and provides a better understanding of potential impacts to the community and ecosystem. The outcome pathway underlies the critical role of determining causality in interpreting impacts of complex mixtures to benthic community and aquatic ecosystem.

确定沉积物毒性的因果关系在水生风险评估中非常重要，但由于痕量污染物在复杂的沉积物基质中的联合毒性，因此存在巨大挑战。已经开发出两种方法，即毒性鉴定评估（TIE）和效果导向分析（EDA）。传统的沉积物TIE通过使用全生物生物测定法来利用与环境相关的优势。然而，由于通常仅评估污染物类别而不是特定污染物，因此他们缺乏有效的方法来明确识别主要贡献者。另外，EDA是通过复杂的分级分离和针对性和非针对性非极性有机有毒物的化学分析来确定沉积物毒性原因的有力工具，但是由于使用了体外生物测定法和详尽的溶剂萃取技术，因此并不总是与环境相关。集成的TIE和EDA方法将提供一种与环境相关且有毒的特定方法，通过结合两种方法的优点来有效地确定沉积物毒性的因果关系。建议将基于生物利用度的提取和定量技术纳入集成方法中，以提高毒性诊断的准确性。除了在综合TIE和EDA方法中考虑生物利用度外，还应考虑不良结局途径的前提。一般来说，TIE和EDA都集中在细胞和生物体水平的不利影响上。在筛选多个毒理学终点时添加基于特征的方法有助于将对细胞和生物体水平的影响扩展到人群水平，并更好地了解对社区和生态系统的潜在影响。结果途径是确定因果关系在解释复杂混合物对底栖生物和水生生态系统影响方面的关键作用。