New quantitative approach for analysis of binary toxic mixtures

Humans generally are exposed simultaneously to a number of toxins, including complex mixtures of unknown and variable origin. Although procedures for assessing the potential toxic risks associated with exposure to individual chemicals are relatively well established, methods for assessing the risks of complex mixtures are still in the developmental stages. One source of considerable uncertainty in these estimates is the potential for interaction among chemicals in complex mixtures. The objective of this work was to gain a better understanding of the effects posed by toxicant interactions and to test a new approach for analyzing the dose-response effects of binary toxic mixtures. This new method of analysis enables a more rapid and quantitative assessment of the interactive effects of pairs of toxic chemicals. A number of experimental studies showing multicompo-nent toxicity were tested using the proposed approach. Both positive and negative interactions of the toxicants were documented for these studies, with significantly acceptable predictive capabilities observed for the model.