Chemical mixtures occur in many settings in the working environment, as most products are actually mixtures of different substances. We use mathematical models based on the additive principle to calculate the toxicological effects of mixtures. I.e. the calculation involves the addition of the toxicity of the single components according to their concentration in the mixture. However, one highly important prerequisite for this is that synergy does not occur. In other words, when adding the effect of the single chemicals together we can say that 1+1=2 and not 1+1= 100 in effect level.

Thus, in order to be able to apply the mathematical models we need to determine the extent to which synergy occurs at human-relevant doses. To do this, we try to disprove the hypothesis that synergy does not occur at human-relevant doses.