TOXICITY OF MIXTURES OF ORGANIC-CHEMICALS TO MICROORGANISMS

Approaches developed by toxicologists in analyzing joint effects of tw o or more chemicals on fish were used to analyze and predict joint eff ects on microorganisms. Based on the results, the joint toxic effects of the 50 chemicals tested in this study can be considered simply addi tive. A quantitative structure-activity relationship (QSAR) technique is proposed for predicting the concentrations of the components of a m ixture that would cause 50% inhibition by joint action. The concentrat ions predicted by the proposed QSAR method are shown to agree well wit h those experimentally measured with r(2) = 0.8 at a level of signific ance, P = 0.0001.