Abstract:  The toxicity data of 42 nitroaromatic compounds related to 50% growth inhibitory concentration (log IGC^-1₅₀) were used to develop Quantitative  structure toxicity relationship to tetrahymena pyriformis.The multiple linear regression method was applied to select the descriptors.The six parametric model were found to be the best which gives  a variance of more than 92% (R²=0.9248). Our results have shown that six parameteric model containing second order connectivity, a physicochemical parameter, distance based Balaban and Balaban type of indices along with indicator parameter play a dominating role in modeling toxicity (log IGC^-1₅₀) . The predictive powers of the models were also discussed by using the method of cross-validation. Our results are comparatively better than the result obtained by E.Estrada and and E.Uriarte.


KEYWORDS: tetrahymena pyriformis, Biological activity, indicator parameter, physicochemical parameters, topological parameters, log IGC^-1₅₀ growth inhibitory concentration, which causes the death of 50% (one half) of a group of test animal.