Objectives

European guidelines for risk assessment of chemicals have recently been modified (REACH, directives for pesticides and biocides) in particular to improve their ecological realism while limiting the use of laboratory animal testing. In addition, the OECD undertook a revision of guidance documents for laboratory bioassays in order to strengthen the relevance of data analysis methods (e.g., OCDE guideline 243). These new official texts all recommend the use of appropriate mathematical and statistical modelling tools, for cognitive and predictive purposes. They promote the optimisation of data analysis (e.g., interpolation between the concentrations tested in bioassays) and the use of modelling as a basis for predicting effects under different environmental conditions (e.g., extrapolation between different scenarios and different exposure times, extrapolation from the individual to the population level, or extrapolation from one species to another).