In the on-going PROOF project "Validation of methods and data for environmental risk assessment offshore" a theoretical framework for integration of biomonitoring into environmental risk assessment procedures was developed. Experimental data were obtained and used to demonstrate that the established framework can be a possible approach to link the biomonitoring with risk assessment. In order to make this approach operative the present project aims to provide sufficient data to complete the links between b iomonitoring and risk assessment, and to develop practical procedures for its use.In relation to produced water discharges there is presently a lack of links between biomonitoring and risk assessment methods. The major benefit of such links is that it e nables judgement of water column monitoring results in relation to expected values. This capability is of key importance for the environmental management of produced water in the Norwegian sector, since the overall goal in our environmental regulation is expressed in terms of (no harmful) effects. Further, it is a proactive requirement for operators to assess the environmental risks and demonstrate that harmful effects are not likely to occur as a result of their operations. In addition to the environme ntal management tools that will be developed, the project will bring new data and knowledge of biological effects in fatty fish species, in particular for species that are economically and ecologically important in the Norwegian Sea and the Barents Sea. T his will be done by long term exposures of capelin, herring, halibut and turbot to crude oil dispersions in four different concentrations. Effects and biomarkers will be measured to provide input to species sensitivity distributions for biomarkers and fit ness, and to form the basis for biomarker based water column monitoring in relation to oil discharges in Norwegian waters.