Estimation of Toxicity Using QSAR

The example of the toxicity estimation using QSAR is based on the TOPKAT system developed by Health Designs, Inc., and is the computer program 

An example of the process is the estimation of the toxicity to D. magna of the simple organic isopropylamine. The compound was given a unique identification and that is usually the Chemical Abstracts Service (CAS) number for easy identification. The chemical structure is then represented in SMILES and the model selected. In the case of the D. magna model the estimate was  

The compound was examined using the structural key and other indices to test how well the keys used in the modeling process described isopropylamine. The computer search of these keys confirmed that isopropylamine was well described by the model. 

The next step is the validation process. Validation is simply an examination of the model with compounds for which toxicity data are available and which were estimated by the QSAR equation. This process provides an indication of how well the model predicts the toxicity of compounds similar to the unknown. In this estimate six compounds were used as comparisons. 

In general, the model overestimated the toxicity of these compounds. Toxicity tests performed with isopropylamine confirmed that the estimated 

---