Single compounds versus combination effects in toxicology

Abstract

Effective protection against harmful effects of toxic substance mixtures requires the ability to assess the combined risk potential of the various constituents. The biological impact of chemical mixtures may arise from independent, additive, synergistic, or antagonistic effects of the single constituents. Mathematical models may be used to characterize these effects. In most cases, models act on the assumption of independent effects or unknown mechanisms of action. However, a mechanistic understanding of interactions among mixture constituents, if available, is the best basis for quantitative predictions of the consequences of co-exposure to different stressors.