Toxicogenomics studies are built on standard toxicology studies, and one major goal of toxicogenomics is to detect relationships between changes in global gene expression and toxicological endpoints, including histopathology, clinical chemistry, and other toxicological parameters. In addition to interpret microarray data appropriately, it is desirable to perform comparative analyses with data obtained from well-characterized toxicants. Therefore, toxicogenomic databases containing high-quality global gene expression and traditional toxicological data are essential. Toxicogenomics is a field of science that deals with the collection, interpretation and storage of information about gene and protein activity within particular cells or tissues of an organism in response to toxic substances. Toxicogenomics combines toxicology with genomics or other high throughput molecular profiling technologies such as transcriptomics, proteomics and metabolomics. Toxicogenomics endeavors to elucidate molecular mechanisms evolved in the expression of toxicity, and to derive molecular expression patterns (i.e., molecular biomarkers) that predict toxicity or the genetic susceptibility to it