Mixture effect models of chemicals and interaction between components

Abstract

Recent development of theoretical models for mixture effect of chemicals is reviewed in terms of the toxic unit summation, the component-based approach and the mixture-based approach. The component-based approach, which is based on the absence of interaction effects among components in a mixture, has two reference models, the independent action model and the concentration addition model. The latter model is regarded as the most efficient mixture model when implementing it into the regulatory framework, because it assumes that component chemicals have similar mode of action and then the adverse effects are cumulative among components, whereby producing more protecting estimates for mixture effects. By extending the concept of component addition, the generalized concentration addition approach is proposed as one of the least data-demanding models of the mixture-based approach.