ABSTRACT
This chapter describes some of the more common models that can be utilized to predict the effects of chemical mixtures from the knowledge on the effects of single chemicals. It focuses on characterizing the joint action of two chemicals or the so-called binary mixtures. The chapter discusses the more general case of the combined effect of any finite number of chemicals. For the purpose of mixture risk assessment, generally two approaches are possible. One approach is the so-called whole mixture approach where the mixture is treated as a single chemical. More commonly, the second approach is the component-based approach and the methodology of risk assessment depends on whether or not the components can be classified as toxicologically similar, independent, or a combination of both. Factorial design is a very efficient and popular method to assess the effect of each factor individually and their interaction in combination with other chemicals.
