(Quantitative) Structure Activity Relationships ((Q)SARs) are the relationships between the structural properties of chemical substances and another property. This other property can be a physico-chemical property or a biological activity, including the ability to cause toxic effects. The models can reduce the number of animal tests necessary in the assessment of chemical substances, increase the information for a given substance (including metabolites and degradation products), and save companies and authorities time and money. In the EU legislation, REACH, it is expected that (Q)SARs will be used as a direct replacement for test data as relevant and reliable models become increasingly available, and as experience in their use becomes more widespread.

Our group develops, buys and validates (Q)SAR models. Our models cover many ADME and toxicity endpoints for e.g. CMR, acute toxicity, allergy, ED and metabolism CYP P450. We focus on so-called "global" models with sub-models for different chemical classes that have large chemical applicability domains. The models are applied both for single substance evaluations and for large scale screenings e.g. for The Advisory List for Selfclassification published by the Danish EPA. We advise on the use and documentation of (Q)SARs in regulatory contexts. This can e.g. be in connection with the upcoming new chemicals legislation REACH and the work in OECD to increase regulatory use and acceptance of (Q)SARs where we e.g. contribute to the development of the (Q)SAR Application Toolbox.