An evaluation of selected valid and mechanistically based SARs for skin sensitisation

Skin sensitisation which clinically is manifested as allergic contact dermatitis is an important health endpoint to be taken into account in the risk assessment of chemicals. In the new EU chemical policy REACH, information on skin sensitisation potential will have to be provided for chemicals manufactured or imported equal to or above 1 tonne/year and it is estimated that the highest number of substances will need to be tested for skin sensitisation. Within REACH, the use of (Q)SARs and other alternative methods is strongly encouraged in order to reduce the number of animal tests. The goal of this project was to test the applicability of SARs and structural alerts for skin sensitisation in the REACH framework. SARs and structural alerts which were found in the literature were analysed and further refined by using a number of examples (substances) that had not been previously used in the derivation of the published SARs. For substances which fit within the boundaries of the proposed alerts, it is assumed that they would be classified as sensitising in accordance with EU classification and labelling rules.