Information on acute and chronic systemic toxicity, arising from the oral, dermal and inhalation routes of exposure, are key elements in the regulatory assessment of chemicals. Traditionally, this information is obtained from animal studies. However, due to animal welfare and cost considerations, alternatives to animal experiments are being sought, and regulatory frameworks are providing an increasing opportunity or obligation to use such methods. This report provides a review of different computational estimation methods for predicting acute and chronic systemic toxicity. It provides an overview of Quantitative Structure-Activity Relationship (QSAR) models published in the literature, commonly used software tools, and available databases suitable for QSAR analysis. It also briefly explains the Threshold of Toxicological Concern (TTC) concept and how this is used in prioritising chemicals for further assessment and preliminary risk characterisation.JRC.DG.I.6 - Systems toxicolog
