A wide-ranging compilation of techniques, this book describes various methods of extrapolation in the framework of ecological risk assessment as well as identifies the data needs and situations where these extrapolations can be most useful applied. It focuses on the extrapolation of chemical effects and also covers the extrapolation of exposures in the context of interactions between toxicants and the matrix. It contains a practical guide to the application of these extrapolation procedures that is designed to be useful to regulators and risk managers at several levels and in the education of students in these environmental disciplines.