Bioaccumulation tests applied in whole effluent assessment: A review

Until recently, the emphasis within whole effluent assessment has been on t he application of bioassays for acute and chronic toxicity. Although the ne ed for additional parameters to assess the ecotoxicological hazard and risk of effluents for receiving water systems has been repeatedly advocated, ot her parameters such as bioaccumulation, genotoxicity, sediment toxicity, an d nutrient impacts are seldom addressed. This paper discusses the potential additional value of including bioaccumulation parameters in whole effluent assessment and methods that can be used for routine assessment. It is conc luded that screening on the presence of potentially bioaccumulating compoun ds leads to a more comprehensive hazard assessment and should therefore be included in whole effluent assessment. A chemical method to assess potentia lly bioaccumulating substances (PBSs) is preferred above methods using orga nisms or classical group parameters such as extractable organic halogens (E OX). In situ studies with organisms are not feasible for routine assessment for a number of reasons, including cost efficiency and matrix problems. Cl assical group parameters such as EOX do not relate to bioaccumulation or to xicity. Chemical methods for assessing bioaccumulation are usually presente d as integrated methods composed of different procedure steps such as pretr eatment, extraction, separation, and detection. However, an optimal method may be constructed by combining procedure steps from different reported met hods. Solid phase microextraction combined with high performance liquid chr omatography or gas chromatography combined with mass spectrometry is regard ed as the preferable method for the assessment of PBSs. Before implementati on in whole effluent assessment, however, the method must be carefully vali dated. Hazard assessment based on bioaccumulation seems feasible. For risk assessment, however, additional information is a prerequisite. Quantitative causal relationships between test assay results and relevant effects on th e population and ecosystem level are absent, hampering the desired upgradin g from hazard to risk assessment.