Interacting Environmental Influences: Concepts of Synergism, Antagonism, and Superposition

Abstract

Since usually an enormous number of different pollutants is simultaneously present in environmental areas, as in the atmosphere, water, and soil, it must be expected that interactions between at least some of these pollutants may occur. Though some examples of such effects have been observed and reported in the literature not very much is known about the combined impact of several pollutants and the environmental policy ignores these effects in defining pollution standards and limits just for single pollutants. Whereas the terms “synergism” or “synergistic effects” are frequently used in different and vague meanings in the literature, there is a remarkable lack of precise definitions of these terms. Starting from definitions of interactions introduced by Ott [1978] and Stehling [1987] a variety of precise concepts of synergism, antagonism, and superposition for two and more interacting influences will be presented in a deterministic context. Furthermore, it will be analysed which properties a function has to have in order to describe such interactions.